CN115281073A

CN115281073A - Crossbreeding method for regulating flowering phase of clove

Info

Publication number: CN115281073A
Application number: CN202211219109.5A
Authority: CN
Inventors: 赵庆柱; 韩瑞东; 杨志莹; 张海良; 刘�英; 初文红; 邱玉宾; 张伟
Original assignee: Weifang Academy Of Agricultural Sciences Weifang Branch Of Shandong Academy Of Agricultural Sciences
Current assignee: Weifang Academy Of Agricultural Sciences Weifang Branch Of Shandong Academy Of Agricultural Sciences
Priority date: 2022-10-08
Filing date: 2022-10-08
Publication date: 2022-11-04

Abstract

The invention provides a crossbreeding method for regulating and controlling the flowering phase of clove, which relates to the technical field of plant crossbreeding and comprises the following steps: the method has the advantages that the flower season meeting of the variety with large early-late difference in the flower period can be regulated, the current situation that the clove late flower variety cannot serve as a male parent to be hybridized with the clove early flower variety is changed, the success rate of hybridization breeding is improved, and the method has the advantages of simplicity, convenience, practicability, stability, reliability and wide applicability.

Description

Crossbreeding method for regulating flowering phase of clove

Technical Field

The invention relates to the technical field of plant cross breeding, in particular to a cross breeding method for regulating and controlling the flowering phase of clove.

Background

The crossbreeding is a conventional technique for breeding improved variety, and is the most common and effective breeding technique, but because different clove varieties or different clove varieties of the same variety have great difference in the early and late flowering stages, flowering asynchronism becomes one of key factors for restricting the crossbreeding of clove.

The most common clove crossbreeding method at present is as follows: storing pollen of the clove early-flowering variety as a male parent, and pollinating the clove late-flowering variety as a female parent when the clove late-flowering variety blooms. The following problems mainly exist in the cross breeding method: firstly, the early flowering variety of clove can only be used as a male parent but can not be used as a female parent; secondly, if the early clove flower variety wants to be hybridized with the late clove flower variety, the pollen of the early clove flower variety needs to be stored in a refrigerated mode, and when the late clove flower variety is hybridized after blooming, the activity of the pollen is easily affected by factors such as pollen storage conditions, and the activity of the pollen is worse when the storage time of the pollen is longer, so that the hybridization success rate is only 50-60%.

Therefore, there is a need for a cross breeding method for regulating the flowering phase of cloves, which can solve the above problems.

Disclosure of Invention

The invention provides a crossbreeding method for regulating the flowering phase of clove, which can regulate the flowering phase meeting of varieties with large difference between early and late flowering phases, changes the current situation that the late flowering variety of clove cannot be used as a male parent to be hybridized with the early flowering variety of clove, improves the success rate of crossbreeding, and has the advantages of simplicity, convenience, practicability, stability, reliability and wide applicability.

The technical scheme of the invention is realized as follows:

a crossbreeding method for regulating and controlling the flowering phase of clove comprises the following steps:

(1) Selecting early clove flower varieties and late clove flower varieties, and measuring and calculating the days of temperature regulation and control;

(2) Regulating and controlling the flowering phase of the early-flowering variety or/and the late-flowering variety of the clove by a temperature control device; the method comprises the following steps: heating the late clove variety by a temperature control device to ensure that the early clove variety grows normally;

or cooling the early clove variety by a temperature control device, so that the late clove variety grows normally;

or heating the late clove variety by a temperature control device, and cooling the early clove variety by the temperature control device;

(3) Carrying out hybrid pollination on the early clove varieties and late clove varieties which meet in flowering phases after control;

(4) And investigating pollination inflorescences of the early clove varieties and late clove varieties meeting in flowering phases after control, and counting the pollination success rate.

As a preferred technical scheme, the steps of heating the variety of the late flowers of clove by a temperature control device are as follows:

(1) Measuring and calculating the heating days of the clove late flower variety;

(2) Covering the clove late flower variety by using a temperature control cover;

(3) Setting an alarm temperature through an APP of a temperature and humidity acquisition instrument;

(4) The first outer cover body and the second outer cover body are wound up by the winding mechanism in the morning every day;

(5) Observing the temperature change condition in the temperature control cover in real time, opening the ventilation opening in time to perform ventilation and cooling when the temperature in the temperature control cover reaches the alarm temperature, and adjusting the size of the ventilation opening according to the temperature rise and fall condition to keep the temperature in the temperature control cover in a certain range all the time;

(6) And closing the ventilation opening in time at night, and covering the first outer cover body and the second outer cover body on the outer wall of the temperature control cover.

As a preferred technical scheme, the steps of using a temperature control device to cool the variety of the lilac premature flowers are as follows:

(1) Measuring and calculating the shading days of the clove early flowering variety;

(2) Irrigating the early flowering clove varieties thoroughly when flower buds begin to sprout, and performing flood irrigation on the early flowering clove varieties;

(3) Watering the permeable early days, shading and cooling the early-flowering clove varieties by using a temperature control cover, and enabling the first outer cover body and the second outer cover body to tightly cover the outer wall of the temperature control cover all the time;

(4) And managing after shading, removing the temperature control cover, and immediately carrying out intertillage and soil moisture conservation.

As a preferred technical scheme, the step of carrying out hybrid pollination on the clove early-flowering variety and the clove late-flowering variety which are controlled to meet in the late-flowering phase is as follows:

(1) After the late clove variety subjected to heating treatment and the early clove variety subjected to cooling treatment enter the early flowering phase, emasculating the early clove variety and inflorescences to be opened of the late clove variety continuously for two days, immediately covering a sulfuric acid paper bag after emasculation, and fixing the temperature control device of the late clove variety again after each emasculation is finished;

(2) After the early clove variety and the late clove variety meeting in the post-flowering phase enter the full-flowering phase, pollen of the early clove variety and the late clove variety is collected for two consecutive days, mutual pollination is carried out on the early clove variety and the late clove variety in a emasculation inflorescence manner, bagging protection is continued after the pollination is finished, and the temperature control device of the late clove variety is fixed again after the pollen collection and pollination are finished each time;

(3) And when the flowering phases of the early clove varieties and the late clove varieties meeting in the flowering phases after regulation and control are basically finished, all the sulfuric acid paper bags are taken down, the early clove varieties enter the field for normal management, and the late clove varieties also enter the field for normal management after the temperature control device is removed.

As a preferred technical scheme, the temperature control device comprises the temperature control cover with an opening-shaped bottom, the rear wall of the temperature control cover is a heat insulation cover body, and the front wall, the top wall and the two side walls of the temperature control cover are transparent cover bodies;

a top frame is fixed on the top wall inside the temperature control cover, a square frame is fixed at the lower end part of the temperature control cover, fixing nails are installed at the bottom of the square frame, four oblique frameworks are installed on the top frame and the square frame together, each oblique framework is tightly attached to the inner wall of the temperature control cover, at least one ventilation opening is arranged on the top wall, the front wall, the rear wall and the two side walls of the temperature control cover, a wind shielding curtain is installed at each ventilation opening, an induction probe is arranged inside the temperature control cover, and the induction probe is connected with a temperature and humidity acquisition instrument;

accuse temperature cover's outer wall coats and is stamped thermal-insulated heat preservation dustcoat, thermal-insulated heat preservation dustcoat includes one first dustcoat body and two the second dustcoat body, first dustcoat body cover in on the roof and the antetheca of accuse temperature cover, each the second dustcoat body all cover in on the lateral wall of accuse temperature cover, be provided with three winding mechanism, each on the back wall of accuse temperature cover first dustcoat body and second dustcoat body all with one winding mechanism is corresponding, each winding mechanism all through detachable construction install in on the accuse temperature cover.

As a preferred technical scheme, the square frame includes four bottom skeletons, every adjacent two the equal mutually perpendicular of bottom skeleton, every adjacent two all install a first mount pad between the bottom skeleton, each bottom skeleton and slant skeleton all through skeleton mount pad assembly with correspond first mount pad and top frame are connected, each the bottom of first mount pad all is fixed with the staple.

As a preferred technical scheme, the winding mechanism comprises a pair of second mounting seats which are oppositely arranged, an outer cover body winding roller and a first pressing roller are jointly mounted on the two second mounting seats, one end of each of the first outer cover body and the second outer cover body is fixed on the corresponding outer cover body winding roller, the other end of each of the first outer cover body and the second outer cover body bypasses the corresponding first pressing roller, a rotating disc and a holding wheel are fixedly mounted at one end of the outer cover body winding roller, a plurality of limiting lugs are arranged on the side wall of the rotating disc, a plurality of limiting grooves are arranged on the corresponding second mounting seats, each limiting groove is matched with the corresponding limiting lug, and each limiting lug is inserted into one limiting groove.

As a preferred technical scheme, ventilation closing mechanism including set up in the windshield wind-up roll of top frame below, the below of windshield wind-up roll is provided with the second compression roller, the second compression roller is followed the axial extension of windshield wind-up roll, second compression roller and windshield wind-up roll all articulate install in on the top frame, torsion spring is installed to the articulated department of windshield wind-up roll and top frame, the upper end of windshield is fixed in on the windshield wind-up roll, the second compression roller compresses tightly on the inner wall of windshield, the both sides of vent all are provided with a rack, each the rack all is perpendicular to the windshield wind-up roll, the lower extreme of windshield is fixed with a horizontal pole, a gear is all installed at the both ends of horizontal pole, each the gear all with correspond the rack meshes, be equipped with a handle that can carry out carrying on the outer wall of windshield.

By adopting the technical scheme, the invention has the beneficial effects that:

the method for regulating and controlling the flowering phase of the clove by hybridization regulates and controls the flowering phase of the late clove variety or/and the early clove variety through a temperature control device, so that the late clove variety can bloom 5-20 days in advance, the early clove variety can bloom 10 days later, the flowering phases of the late clove variety and the early clove variety within 30 days of the flowering phase difference can meet each other, the current situation that the late clove variety cannot be used as a male parent to be hybridized with the early clove variety is changed, the pollen of the early clove variety does not need to be refrigerated and stored, and the pollen of the late clove variety and the early clove variety can be hybridized and pollinated immediately after being mature, thereby effectively improving the success rate of hybridization.

Because the temperature control device comprises the temperature control cover, the top frame, the oblique framework, the square frame and the induction probe, compared with an arched shed and a sunlight greenhouse which are large in size, the temperature control device is small in size, convenient to move and reusable, and the technical problem of flowering asynchronism in clove crossbreeding is solved; meanwhile, the temperature and humidity in the temperature control cover can be monitored in real time by using the induction probe, monitored temperature and humidity data can be transmitted to a mobile phone of a manager, so that the temperature and humidity can be remotely checked by a plurality of people in real time, the manager can timely process the temperature and humidity data according to the monitored data, the manager does not need to manually detect the temperature and humidity, and intelligent and accurate control over the regulation and control of the flowering phase of the clove is realized.

The temperature control cover comprises a heat insulation cover body and a transparent cover body, wherein the heat insulation cover body covers the outer side of the transparent cover body, the heat insulation cover body and the transparent cover body are provided with ventilation openings, and the ventilation openings are provided with wind screens; for the cooling treatment of the clove early-flowering variety, the heat insulation cover body and the heat insulation cover play a role in heat insulation and shading in the daytime, and play a role in heat preservation at night, so that the cooling treatment effect of the temperature control device on the clove early-flowering variety is ensured, and the flowering phases of the clove early-flowering variety and the clove late-flowering variety can meet each other.

Because the wind screen is arranged at the vent through the ventilation opening and closing mechanism, the elasticity of the torsion spring is smaller than the meshing force between the gear and the rack, so that the arrangement of the gear and the rack ensures that the cross rod at the lower end part of the wind screen can stop at any position, and the arrangement of the torsion spring ensures that the wind screen can be smoothly wound on the wind screen winding roller, thereby realizing the free adjustment of the opening size of the vent, further facilitating the control of managers on the temperature inside the temperature control cover, and ensuring the heating treatment effect of the temperature control device on the clove late flower variety.

Because the temperature control cover is internally provided with the inductive probe, in the temperature control cover, the inductive probe can monitor the temperature and the humidity in the temperature control cover in real time and transmit the detected data to the temperature and humidity acquisition instrument, and the temperature and humidity acquisition instrument not only can display and record the temperature and the humidity in the temperature control cover in real time, but also can transmit the data to the APP for managers to look over remotely through the mobile phone terminal in real time.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of the structure of the present invention;

FIG. 2 is a schematic side view of FIG. 1;

FIG. 3 is a rear view of FIG. 1;

FIG. 4 is an enlarged view of the structure at A in FIG. 1;

FIG. 5 is an enlarged view of the structure at B in FIG. 1;

FIG. 6 is an enlarged view of the structure at C in FIG. 1;

FIG. 7 is a schematic view of the thermal insulation cover of the present invention in a rolled state.

Wherein: 1. a temperature control cover; 2. a heat insulation cover body; 3. a transparent cover body; 4. a top frame; 5. a square frame; 6. fixing nails; 7. an oblique framework; 8. a vent; 9. a wind screen; 10. an inductive probe; 11. a temperature and humidity acquisition instrument; 12. a first outer cover; 13. a second housing body; 14. a bottom skeleton; 15. a first mounting seat; 16. magic tape; 17. a first hinge mount; 18. a second hinge mount; 19. a first plug-in block; 20. a first compression spring; 21. inserting holes; 22. a locking block; 23. a second compression spring; 24. a locking groove; 25. a push rod; 26. an extension spring; 27. a second insertion block; 28. a second mounting seat; 29. an outer cover body wind-up roll; 30. a first pressure roller; 31. rotating the disc; 32. a wheel is held; 33. a limiting bump; 34. a limiting groove; 35. a fixing plate; 36. a fixed seat; 37. compressing the groove; 38. a slide bar; 39. a third compression spring; 40. a limiting sleeve; 41. a wind-shield curtain wind-up roll; 42. a second pressure roller; 43. a torsion spring; 44. a rack; 45. a cross bar; 46. a gear; 47. a handle.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

(1) And selecting the early clove variety and late clove variety, and calculating the days for temperature regulation and control.

In the invention, the clove late flower variety is heated before the flower buds germinate, the internal temperature of the temperature control device is controlled below 30 ℃ according to the real-time air temperature condition until the clove late flower variety completes the hybrid pollination with the clove early flower variety, then the temperature control device is removed, the heating time length is determined according to the actual flowering phase requirement, 5 days are added to the actual days in advance of the clove late flower variety, namely the days in advance, the heating treatment can be carried out for 25 days at most, and the flowering phase of the clove late flower variety is advanced for 20 days.

Meanwhile, the temperature of the lilac early flower variety is reduced before the bud of the lilac early flower variety buds, the shading time length is determined according to the actual florescence requirement, 2 days are added to the days needing to be delayed to obtain the days needing to be shaded, the maximum shading time can be 12 days, and the florescence of the lilac early flower variety is delayed by 10 days.

(2) And regulating and controlling the flowering phase of the early-flowering variety or/and the late-flowering variety of the clove by a temperature control device, wherein the regulation and control method comprises the following steps: the late-flowering clove variety is heated by a temperature control device, and the early-flowering clove variety grows normally.

Or the temperature control device is used for cooling the clove early flower variety, so that the clove late flower variety grows normally.

Or heating the clove late flower variety by the temperature control device, and cooling the clove early flower variety by the temperature control device.

(3) And carrying out hybrid pollination on the early clove varieties and late clove varieties meeting in the controlled flowering phases.

(4) And investigating pollination inflorescences of the early clove varieties and the late clove varieties meeting in the flowering phases after control, and counting the pollination success rate.

In the first embodiment, the late clove variety is heated by a temperature control device, so that the early clove variety grows normally.

In this embodiment, the late clove variety is clove hybrid 'james', the early clove variety is clove 'porcelain blue', the flowering period of 'james' is from late 4 months to early 5 months, the flowering period is about 20 days, in this embodiment, 10 'james' with the 3-year seedling age are selected as target plants of the late clove variety, the flowering period of 'porcelain blue' is from late 4 months to late 4 months, the flowering period is about 15 days, in this embodiment, 10 'porcelain blues' with the 4-year seedling age are selected as target plants of the early clove variety, and the difference between the flowering period days of 'james' and 'porcelain blues' is 15-18 days.

The method comprises the following specific steps:

(1) And calculating the heating days. Based on the difference of the florescence days of 'porcelain blue' and 'James', the addition of 5 days results in 20-23 days. Therefore, if 'james' were to meet the 'china blue' flowering in late 4 months, it would be necessary to heat up 'james' 20-23 days before their buds emerged.

(2) And installing a temperature control device. Referring to 'James' past phenological data, the germination period is about 3 months and 22 days, so that when the date is 3 months and 1 day in the year, the date is determined, and the date is covered by a temperature control device outside the date for heating treatment.

(3) And setting an alarm temperature. Downloading temperature and humidity acquisition instrument management software and expanding cloud Internet of things APP at a mobile phone end of a manager, networking and setting the alarm temperature of the temperature and humidity acquisition instrument 11 to be 30 ℃.

(4) And controlling the temperature. Controlling the temperature in the device to be below 30 ℃ according to the real-time air temperature condition, opening the ventilation opening in time to ventilate and cool when the temperature in the temperature control device reaches 30 ℃, adjusting the ventilation size of the ventilation opening according to the temperature rising and falling condition to keep the daytime temperature in the temperature control device between 20 and 30 ℃, closing the ventilation opening in time at night and covering a heat insulation and preservation outer cover to preserve heat.

(5) And performing cross pollination. The 'James' target plant is managed according to the method until the current year is 4 months and 20 days, in the period, 4 months and 5 days 'James' enter the initial flowering stage, 4 months and 6 days 'porcelain blue' normally enter the initial flowering stage, the flowering stages of the two meet, and the two parents are hybridized.

4, 6 days and 7 days, selecting the inflorescences which are about to open by 'James' and 'porcelain blue' for 2 days continuously, emasculating, and immediately covering sulfuric acid paper bags after emasculation, wherein the number of emasculation inflorescences is 20 for each variety.

From 8 days in 4 months to 16 days in 4 months, 'james' and 'porcelain blue' enter into the full bloom stage, during which the pollen of the two is mature and can be taken at any time. Collecting pollen of Jaemse and porcelain blue for 2 days continuously in 8 days in 4 months and 9 days in 4 months, pollinating the pollen of the Jaemse and porcelain blue for the emasculation inflorescence of the other party, and continuously bagging and protecting after pollination. And after emasculation, pollen collection and pollination are finished each time, the temperature control device outside the target plant of 'James' is fixed again.

And 4, 20 days in 4 months, basically finishing the flowering periods of the two, completely taking off the sulfuric acid paper bags, enabling the porcelain blue to enter the field for normal management, and enabling the James' to enter the field for normal management after the temperature control device is removed.

(6) And counting results. And 4, in 30 days after 4 months, the pollination inflorescences of 'james' and 'porcelain blue' are investigated, and the pollination success rate is counted.

The results were: 40 inflorescences are all fruited, and the pollination success rate reaches 100 percent.

And in the second embodiment, the temperature control device is used for cooling the clove early flower variety, so that the clove late flower variety can grow normally.

In this embodiment, the early-flowering variety of clove is selected from lilac 'golden time', the late-flowering variety of clove is selected from euro-clove 'macken', the flowering phase of 'golden time' is from late 3 months to late 4 months, and the flowering phase is about 15 days, in this embodiment, 10 'golden time' of 4 seedling years are selected as the target plants of the early-flowering variety of clove, 'macken' has a flowering phase from late 4 months to middle 4 months, and the flowering phase is about 15 days, in this embodiment, 10 'macken' of 4 seedling years are selected as the target plants of the late-flowering variety of clove, and the number of days of the flowering phase difference between 'golden time' and 'macken' is 8-10 days.

The method comprises the following specific steps:

(1) And determining the number of light-shading days. The difference days between 'golden time' and 'Macken' flowering phases is 8-10 days as the basis for measurement, and 10-12 days are obtained by adding 2 days. Therefore, if the two florescence meet each other, the 'golden time light' should be shaded and cooled for 10-12 days.

(2) And irrigating the soil thoroughly. According to actual observation, in the current year of 3 months and 10 days, the 'golden time' flower buds begin to sprout, and at the moment, the target plants are subjected to flood irrigation, so that the ground temperature is delayed to be increased.

(3) And shading light and cooling. On the next day, the gold time light is covered by a temperature control device for 24 hours without interruption, and the shading days are 12 days.

(4) And managing after shading. And (3) shading the golden time light to 3, 23 days in the year, removing a temperature control device, immediately performing intertillage and soil moisture conservation, and promoting the ventilation and temperature rise of the ground surface.

(5) And performing cross pollination. 4, 8 days, the 'Maken' planted in the field enters the initial flowering phase, and 4, 10 days, the 'golden time' enters the initial flowering phase, and the flowering phases meet.

The hybridization scheme with 'golden time light' as a male parent and 'McKen' as a female parent: selecting a 'Macken' inflorescence to be opened for emasculation for 2 consecutive days after 4 months, 9 days and 10 days, and immediately covering a sulfuric acid paper bag after the emasculation, wherein the emasculation quantity is 20. Collecting 'golden time light' pollen for pollination for 2 consecutive days of 4 months, 11 days and 12 days, and continuing bagging protection after pollination.

The hybridization scheme with 'golden time light' as a female parent and 'Maken' as a male parent: and 4, taking 10 days and 11 days in 4 months, emasculating the opened inflorescences by selecting 'golden time light' for 2 consecutive days, and immediately covering sulfuric acid paper bags after emasculation, wherein the emasculation quantity is 20. Collecting the 'Maiken' pollen for pollination for 2 consecutive days at 12 days and 13 days in 4 months, and continuing bagging protection after pollination.

4, 22 days, the 'golden time' and the 'Macken' are basically finished, at the moment, the sulfuric acid paper bag is removed, and the field is normally managed.

(6) And counting results. And 4, after 30 days in 4 months, investigating pollination inflorescences of 'golden time light' and 'Macken' and counting the pollination success rate.

And in the third embodiment, the late clove variety is heated by the temperature control device, and the early clove variety is cooled by the temperature control device.

In this embodiment, the early flowering clove is selected from zikui purple clove, the late flowering clove is selected from a hybrid clove, james, the flowering phase of zikui is from late 3 months to late 4 months, about 15 days, the flowering phase of james is from late 4 months to late 5 months, and about 20 days, in this embodiment, 4-year-old zikui 10 plants are selected as target plants of the early flowering clove, 3-year-old james 10 plants are selected as target plants of the late flowering clove, and the early and late flowering days of the two are 25-30 days apart.

The method comprises the following specific steps:

(1) And determining the number of days for regulating the temperature. According to the maximum time limit of 25 days for heating treatment as the number of heating days, the late variety 'James' is heated, and the 'James' flowering phase is obtained 20 days ahead of time; and (3) shading and cooling the early flower variety 'Zikui' according to the condition that the longest time limit of shading and cooling treatment is 12 days as the number of cooling treatment days, so that the 'Zikui' flowering phase delay is 10 days.

According to the temperature regulation and control scheme, meeting of 'james' and 'violkuin' in flowering phase can be realized.

(2) And heating the late-flowering clove variety Jaemshi.

(1) And installing a temperature control device. The germination period of the past phenological data of 'james' is about 22 days in 3 months, the former phenological data is heated in advance by 25 days, and the former phenological data is covered by a special temperature control device at 27 days in 2 months in the current year.

(2) And setting an alarm temperature. Downloading temperature and humidity acquisition instrument management software Pengyun Internet of things APP at a mobile phone terminal of a manager, networking and setting the alarm temperature of the temperature and humidity acquisition instrument 11 to be 30 ℃.

(3) And (5) temperature control management. Controlling the temperature in the device to be below 30 ℃ according to the real-time air temperature condition, opening the ventilation opening in time to ventilate and cool when the temperature in the temperature control device reaches 30 ℃, adjusting the size of the ventilation opening according to the temperature rising and falling condition to keep the daytime temperature in the temperature control device between 20 and 30 ℃, closing the ventilation opening in time at night and covering a heat insulation and preservation outer cover to preserve heat.

(3) And cooling the lilac early flower variety Zikui.

(1) And (5) irrigating thoroughly. According to actual observation, the 'Zikui' flower buds begin to sprout at 11 days 3 months in the year, and at the moment, the target plants are subjected to flood irrigation to delay the increase of the ground temperature.

(2) Shading light and cooling. On the next day, the violkui is covered by a temperature control device, and is subjected to uninterrupted shading and cooling treatment for 24 hours, wherein the shading days are 12 days.

(3) And (5) managing after shading. And shading the Zikui to 3 months and 24 days in the year, removing the temperature control device, immediately performing intertillage and soil moisture conservation, and promoting the ventilation and temperature rise of the earth surface.

(4) And performing cross pollination. Managing 'james' according to the method of the step (2) to 4 months and 20 days in the year. During this time, 4 months, 5 days 'james' entered the beginning of the bloom. 4, 6 days and 6 days, namely Zikui enters the initial flowering phase, the two flowering phases meet, and the two florescence phases are used as male parents and female parents for hybridization.

And selecting 'Jaemshi' and 'Zikui' for 2 consecutive days after 4 months and 6 days and 7 days, namely castrating the opened inflorescences, and immediately covering sulfuric acid paper bags after castration, wherein the castration inflorescences are 20 in each variety.

4 months and 8 days, the James ' and the Zikui ' enter the full-bloom stage and continue to 4 months and 16 days, and the pollen of the James ' and the Zikui is mature and can be taken along with the pollen. Collecting ' James ' Zikui ' pollen for 2 consecutive days at 8 days in 4 months and 9 days in 4 months, pollinating mutually for emasculation inflorescences, and continuing bagging protection after pollination; and after emasculation, pollen collection and pollination are finished each time, the external temperature control device of 'James' is fixed again.

After 20 days in 4 months, basically finishing the florescence of the two plants, and completely removing the sulfuric acid paper bags, 'Zikui' and entering the field for normal management; 'james' also entered into normal field management after removing the temperature control device.

(5) And counting results. And 4, surveying pollination inflorescences of Jaemshi and Zikui for 30 days in 4 months, and counting the pollination success rate.

In the invention, the blooming of the early flowering clove variety can be delayed by 10 days, and the blooming of the late flowering clove variety is advanced by 5-20 days, so that the reasonable regulation and control of the flowering phases of the early flowering clove variety or/and the late flowering variety are realized, and the late flowering clove variety and the early flowering clove variety with the flowering phases within 30 days can be hybridized as a male parent and a female parent, so that the current situation that the late flowering clove variety cannot be hybridized as a male parent and the early flowering clove variety is changed; meanwhile, the pollen of the clove early-flowering variety does not need to be refrigerated and stored, and after the pollen of the clove late-flowering variety and the pollen of the clove early-flowering variety are mature at the same time, cross pollination can be carried out immediately, so that the success rate of cross breeding is effectively improved; the method is not only suitable for regulating and controlling the flowering phase of the clove, but also suitable for regulating and controlling the flowering phase meeting of various woody plants except the clove so as to perform cross breeding on the early-flowering variety and the late-flowering variety, and has wide application range and outstanding benefit.

As shown in fig. 1-7, the temperature control device includes a temperature control cover 1 with an open bottom, a heat insulation cover 2 is disposed on the rear wall of the temperature control cover 1, and transparent covers 3 are disposed on the front wall, the top wall and the two side walls of the temperature control cover 1.

A top frame 4 is fixed on the top wall in the temperature control cover 1, and a square frame 5 is fixed at the lower end part of the temperature control cover 1, wherein the bottom of the temperature control cover 1 is square, the side length of the bottom is 1.5-2m, and the height of the temperature control cover 1 is 1.5-2m; the bottom of the square frame 5 is provided with a fixing nail 6, and in the embodiment, the fixing nail 6 is a large nail made of steel; four oblique frameworks 7 are jointly installed on the top frame 4 and the square frame 5, each oblique framework 7 is tightly attached to the inner wall of the temperature control cover 1, the top wall of the temperature control cover 1, the front wall, the rear wall and the two side walls are respectively provided with at least one vent 8, each vent 8 is provided with a wind screen 9 through a ventilation opening-closing mechanism, an induction probe 10 is arranged inside the temperature control cover 1, the induction probe 10 is connected with a temperature and humidity acquisition instrument 11, in the embodiment, the transparent cover body 3 can be made of a transparent plastic film and is adhered to the top frame 4, the square frame 5 and the oblique frameworks 7, the wind screen 9 is made of the same material as that of the transparent cover body 3, the temperature and humidity acquisition instrument 11 is a Pengyun brand S10A type remote temperature and humidity acquisition instrument produced by Xuzhou electronic technology Limited, the induction probe 10 of the temperature and humidity acquisition instrument 11 is fixed inside the temperature and humidity control cover 1 and vertically suspended downwards, and the machine body of the temperature and humidity acquisition instrument 11 is arranged outside the temperature and humidity control cover 1.

The outer wall of the temperature control cover 1 is covered with a heat insulation cover, the heat insulation cover comprises a first cover body 12 and two second cover bodies 13, the first cover body 12 covers the top wall and the front wall of the temperature control cover 1, each second cover body 13 covers the outer side wall of the temperature control cover 1, three winding mechanisms are arranged on the rear wall of the temperature control cover 1, each first cover body 12 and each second cover body 13 correspond to one winding mechanism, each winding mechanism is installed on the temperature control cover 1 through a detachable mechanism, in the embodiment, the heat insulation cover and the heat insulation cover body 2 both adopt black felts, silver powder coatings are sprayed on the outer surfaces of the heat insulation cover and the heat insulation cover body 2, the heat insulation cover and the heat insulation cover body 2 are processed according to the shape and the size of the temperature control cover 1, the heat insulation cover and the heat insulation cover body 2 can completely cover the temperature control cover 1, and the inner surfaces of the first cover body 12 and the second cover body 13 are fixedly connected with the outer surface of the temperature control cover 1 through magic tapes 16.

The square frame 5 comprises four bottom frameworks 14, every two adjacent bottom frameworks 14 are perpendicular to each other, a first mounting seat 15 is installed between every two adjacent bottom frameworks 14, each bottom framework 14 and the oblique framework 7 are connected with the corresponding first mounting seat 15 and the top frame 4 through framework mounting seat assemblies, fixing nails 6 are fixed at the bottom of each first mounting seat 15, and in the embodiment, the bottom frameworks 14 and the oblique frameworks 7 are all carbon fiber tubes.

Wherein, the skeleton mount pad assembly includes the articulated seat of first articulated seat 17 and second 18, and the one end of each bottom skeleton 14 and slant skeleton 7 all is provided with a first articulated seat 17, and the other end of each bottom skeleton 14 and slant skeleton 7 all is provided with the articulated seat of second 18.

One end of the first hinge seat 17 is hinged to the corresponding first mounting seat 15, a first plug block 19 is slidably mounted at the other end of the first hinge seat 17, a first compression spring 20 is mounted between one end of the first plug block 19 and the first hinge seat 17, plug holes 21 are formed in each of the bottom framework 14 and the inclined framework 7, the other end of the first plug block 19 is inserted into the corresponding plug hole 21, a locking block 22 is mounted at one end of the first plug block 19 inserted into the plug holes 21, one end of the locking block 22 is hinged to the first plug block 19, a second compression spring 23 is mounted between the other end of the locking block 22 and the first plug block 19, a locking groove 24 is formed in one side of the locking block 22, the outside of the locking block 22 is inserted into the locking groove 24, a push rod 25 is slidably mounted in the locking groove 24, an extension spring 26 is mounted between the push rod 25 and the inner wall of the locking groove 24, one end of the push rod 25 abuts against the locking block 22, and the other end of the push rod 25 extends out of the bottom framework 14 or the inclined framework 7.

One end of the second hinged seat 18 is hinged and installed on the corresponding first installation seat 15 and the top frame 4, the other end of the second hinged seat 18 is fixed with a second insertion block 27, and the second insertion block 27 is inserted into the corresponding insertion groove.

In the invention, the framework mounting seat assembly is convenient for disassembling the temperature control cover 1, and the volume of the temperature control device during storage is reduced, so that the temperature control cover 1 can be stored for a long time.

Moreover, the winding mechanism comprises a pair of second mounting seats 28 which are arranged oppositely, an outer cover body winding roller 29 and a first pressing roller 30 are mounted on the two second mounting seats 28 together, one end of each of the first outer cover body 12 and the second outer cover body 13 is fixed on the corresponding outer cover body winding roller 29, the other end of each of the first outer cover body 12 and the second outer cover body 13 bypasses the corresponding first pressing roller 30, one end of the outer cover body winding roller 29 is fixedly provided with a rotating disc 31 and a holding wheel 32, the side wall of the rotating disc 31 is provided with a plurality of limiting lugs 33, the corresponding second mounting seats 28 are provided with a plurality of limiting grooves 34, each limiting groove 34 is matched with the limiting lug 33, and each limiting lug 33 is inserted into one limiting groove 34.

The detachable mechanism comprises a pair of fixing plates 35, each fixing plate 35 is installed on the corresponding second installation seat 28, a fixing seat 36 is arranged on the inner side of each fixing plate 35, each fixing seat 36 is fixed on the temperature control cover 1, a pressing groove 37 is formed in the outer wall of each fixing seat 36, each fixing plate 35 is pressed on the inner wall of the pressing groove 37, one fixing plate 35 is installed on the corresponding second installation seat 28 in a sliding mode through a sliding rod 38, the sliding rod 38 slides along the axial direction of the outer cover body winding roller 29, a third compression spring 39 is installed between the sliding rod 38 and the second installation seat 28, a limiting sleeve 40 is installed on the sliding rod 38 in a threaded mode, and the limiting sleeve 40 is arranged between the corresponding fixing plate 35 and the second installation seat 28.

In addition, the ventilation opening and closing mechanism comprises a wind-shield curtain winding roller 41 arranged below the top frame 4, a second pressing roller 42 is arranged below the wind-shield curtain winding roller 41, the second pressing roller 42 extends along the axial direction of the wind-shield curtain winding roller 41, the second pressing roller 42 and the wind-shield curtain winding roller 41 are both hinged to the top frame 4, a torsion spring 43 is arranged at the hinged position of the wind-shield curtain winding roller 41 and the top frame 4, the upper end of the wind-shield curtain 9 is fixed on the wind-shield curtain winding roller 41, the second pressing roller 42 is pressed on the inner wall of the wind-shield curtain 9, racks 44 are arranged on both sides of the vent 8, each rack 44 is perpendicular to the wind-shield curtain winding roller 41, a cross rod 45 is fixed at the lower end of the wind-shield curtain 9, gears 46 are arranged at both ends of the cross rod 45, each gear 46 is meshed with the corresponding rack 44, and a lifting handle 47 capable of lifting is arranged on the outer wall of the wind-shield curtain 9.

In the invention, the ventilation openings 8 are positioned at the middle lower parts and the tops of the front wall, the rear wall and the two side walls of the temperature control cover 1, the ventilation openings 8 on the front wall, the rear wall and the two side walls of the temperature control cover 1 are squares with the side length of 40cm and are shielded by the wind-shielding curtain 9 with the side length of 50cm, the ventilation opening 8 at the top of the temperature control cover 1 is positioned at the center of the top of the temperature control cover 1 and is squares with the size of 50cm and is shielded by the wind-shielding curtain 9 with the size of 60 cm.

The installation method of the temperature control device comprises the following steps:

firstly, inserting the upper end of the oblique framework 7 into a corresponding second hinge seat 18 on the top frame 4 through a second insertion block 27 and an insertion hole 21, then inserting a first insertion block 19 on a first installation seat 15 into the insertion hole 21 at the lower end of the oblique framework 7, and simultaneously inserting the outer part of a locking block 22 on the first insertion block 19 into a locking groove 24 under the elastic force action of a second compression spring 23 to complete the installation of the oblique framework 7;

secondly, inserting the second inserting block 27 on the first mounting seat 15 into the inserting hole 21 at one end of the bottom framework 14, then inserting the first inserting block 19 on the other first mounting seat 15 into the inserting hole 21 at the other end of the bottom framework 14, and simultaneously inserting the outer part of the locking block 22 on the first inserting block 19 into the locking groove 24 to complete the mounting of the square frame 5;

thirdly, after the top frame 4, the oblique framework 7 and the square frame 5 are all installed, an integral frame of the temperature control cover 1 is formed, then transparent cover bodies 3 are adhered to the top wall, the front wall and the two side walls of the integral frame together, a heat insulation cover body 2 is fixed on the rear wall of the integral frame, a wind screen 9 is installed on the inner side of the ventilation opening 8 through a ventilation opening and closing mechanism, and the ventilation opening 8 is opened and closed through the wind screen 9;

fourthly, placing a fixing plate 35 on the winding mechanism into the corresponding pressing groove 37, then pressing the other fixing plate 35 inwards to enable the sliding rod 38 to slide inwards, increasing the distance between the fixing plate 35 and the other fixing plate 35, aligning the fixing plate 35 with the corresponding pressing groove 37, then loosening the fixing plate 35, enabling the fixing plate 35 to gradually approach the corresponding fixing seat 36 and press in the corresponding pressing groove 37 under the elastic force action of a third compression spring 39, then rotating a limiting sleeve 40 to enable the limiting sleeve 40 to move on the sliding rod 38, enabling the limiting sleeve 40 to gradually approach the second mounting seat 28, and finally enabling the end of the limiting sleeve 40 to abut against the end of the second mounting seat 28, so that the fixing of the fixing plate 35 is realized, and meanwhile, enabling the two fixing plates 35 to be firmly pressed in the pressing groove 37, so that the winding mechanism is mounted;

fifthly, the fixing nails 6 are all inserted into the soil at the preset position to fix the temperature control cover 1, and the target plant of the selected early clove variety or late clove variety is located on the inner side of the temperature control cover 1.

The operation steps of heating the clove late flower variety by using the temperature control device are as follows:

(1) And measuring and calculating the heating days of the clove late flower variety.

(2) And installing the temperature control device, and using the temperature control cover 1 to cover the clove late-flowering variety.

(3) The APP through the temperature and humidity acquisition instrument 11 sets the alarm temperature, and in the embodiment, the alarm temperature of the temperature and humidity acquisition instrument 11 is set to be 30 ℃.

(4) In every morning, utilize winding mechanism to get up first outer cover body 12 and second outer cover body 13 rolling, in this embodiment, at 8 o' clock every morning, managers will tear first outer cover body 12 and second outer cover body 13 magic subsides 16 everywhere earlier, make the surface separation of first outer cover body 12 and second outer cover body 13 and control by temperature change cover, then rotate the wheel 32 of holding on the winding mechanism, it is rotatory to hold wheel 32 rotation drive outer cover body wind-up roll 29, roll first outer cover body 12 and second outer cover body 13, make sunshine shine in controlling temperature cover 1 through the translucent cover body 3 on controlling temperature cover 1, make the temperature rise in controlling temperature cover 1.

(5) According to the temperature monitoring device, when the temperature inside the temperature control cover 1 reaches the alarm temperature, the vent 8 is opened in time to perform ventilation and cooling, the size of the vent 8 is adjusted according to the temperature rising and falling conditions, so that the temperature inside the temperature control cover 1 is always kept in a certain range, in the temperature monitoring device, the alarm temperature is 30 ℃, the rear wall of the temperature control cover 1 faces the north, the front wall faces the south, the two side walls face the east and west respectively, the temperature inside the temperature control cover 1 is monitored by the inductive probe 10 in real time, detected data are transmitted to an APP at a mobile phone end of a manager through the temperature and humidity acquisition instrument 11, and the manager observes the temperature change condition inside the temperature control cover 1 in real time through the APP of the temperature and humidity acquisition instrument 11.

When the alarm temperature is reached for the first time, the ventilation openings 8 on the top wall of the temperature control cover 1 are opened, meanwhile, the ventilation openings 8 on the two side walls of the temperature control cover 1 are opened by one half, and if the temperature is reduced to be within 30 ℃, the ventilation state is continuously kept; if the temperature reaches the alarm temperature again, the ventilation openings 8 on the two side walls are completely opened immediately; if the temperature still continues to rise, the ventilation openings 8 on the front wall and the rear wall of the temperature control cover 1 are opened completely; and starting at three points in the afternoon, gradually reducing the external temperature, gradually closing the opened vent 8 by a manager, and completely closing the vent 8 when the temperature is reduced to 25 ℃, so that the temperature inside the temperature control cover 1 is always kept in the range of 25-30 ℃.

(6) In the invention, a manager rotates the holding wheel 32 again to loosen the first outer cover body 12 and the second outer cover body 13 on the outer cover body winding roller 29, pulls the first outer cover body 12 and the second outer cover body 13 to cover the temperature control cover 1, and fixes the first outer cover body 12 and the second outer cover body 13 on the outer surface of the temperature control cover 1 by the magic tape 16, thereby avoiding the influence on the heat preservation effect caused by the fact that the first outer cover body 12 and the second outer cover body 13 are blown up by wind.

The operation steps of using the temperature control device to cool the clove early blossoming variety are as follows:

(1) And calculating the shading days of the clove early flowering variety.

(2) And irrigating the early flowering clove varieties thoroughly, and performing large water flood irrigation on the early flowering clove varieties according to actual observation when flower buds of the early flowering clove varieties begin to sprout so as to delay the ground temperature rise.

(3) The temperature control device is installed, the temperature control cover 1 is used for covering the clove early-flowering variety, the first outer cover body 12 and the second outer cover body 13 are enabled to cover the outer surface of the temperature control cover 1 all the time tightly, the first outer cover body 12 and the second outer cover body 13 are utilized for preserving heat inside the temperature control cover 1, in the embodiment, the temperature control device is installed on the second day of irrigation and water permeation, 24-hour uninterrupted shading and cooling treatment is carried out on the clove early-flowering variety, and the shading days are 12 days.

(4) And managing after shading, removing the temperature control device after the shading days, and immediately carrying out intertillage and soil moisture conservation to promote the ventilation and temperature rise of the ground surface.

The steps of carrying out hybrid pollination on the clove early flower variety and the clove late flower variety which meet each other in the controlled late flowering phase are as follows:

(1) And after the late clove variety subjected to heating treatment and the early clove variety subjected to cooling treatment enter the initial flowering period, emasculating the inflorescences to be opened of the early clove variety and the late clove variety for two consecutive days, immediately covering a sulfuric acid paper bag after emasculation, and fixing the temperature control device of the late clove variety again after the emasculation is finished every time.

(2) And after the early clove flower variety and the late clove flower variety enter the full-bloom stage, the pollen of the early clove flower variety and the pollen of the late clove flower variety are collected for two consecutive days, the pollen is pollinated for a emasculation inflorescence, the bagging protection is continued after the pollination is finished, and the temperature control device of the late clove flower variety is fixed again after the pollen collection and pollination are finished each time.

(3) And when the flowering period of the early clove variety and the late clove variety is basically finished, all the sulfuric acid paper bags are taken down, the early clove variety enters the field for normal management, and the late clove variety also enters the field for normal management after the temperature control device is removed.

In conclusion, the crossbreeding method for regulating the flowering phase of the clove, provided by the invention, can regulate the flowering phase meeting of varieties with large difference between early and late flowering phases, changes the current situation that the late flowering variety of the clove cannot be used as a male parent to be crossbred with the early flowering variety of the clove, improves the success rate of crossbreeding, and has the advantages of simplicity, convenience, practicability, stability, reliability and wide applicability.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the scope of the present invention, which is intended to cover any modifications, equivalents, improvements, etc. within the spirit and scope of the present invention.

Claims

1. A crossbreeding method for regulating and controlling the flowering phase of clove is characterized by comprising the following steps:

(1) Selecting early clove flower varieties and late clove flower varieties, and calculating the days for temperature regulation and control;

or cooling the early-flowering clove variety by a temperature control device, so that the late-flowering clove variety grows normally;

or heating the clove late flower variety by a temperature control device, and cooling the clove early flower variety by the temperature control device;

2. The crossbreeding method for regulating and controlling the flowering phase of clove according to claim 1, wherein the step of heating the clove late flower variety by the temperature control device comprises the following steps:

(4) The first outer cover body and the second outer cover body are wound by the winding mechanism in the morning every day;

(5) Observing the temperature change condition inside the temperature control cover in real time, opening the ventilation opening in time for ventilation and cooling when the temperature inside the temperature control cover reaches the alarm temperature, and adjusting the size of the ventilation opening according to the temperature rise and fall condition to keep the temperature inside the temperature control cover within a certain range all the time;

3. The crossbreeding method for regulating and controlling the flowering phase of clove according to claim 1, wherein the step of using a temperature control device to cool the early flowering variety of clove comprises the following steps:

(1) Measuring and calculating the shading days of the early flowering variety of the clove;

(2) Irrigating the early flowering clove variety with water when the flower buds begin to sprout, and performing large water flood irrigation on the early flowering clove variety;

(3) Watering the permeable next day, shading and cooling the early-flowering clove varieties by using a temperature control cover, and enabling the first outer cover body and the second outer cover body to tightly cover the outer wall of the temperature control cover all the time;

4. The crossbreeding method for regulating the flowering phase of clove according to claim 2 or 3, wherein the step of crossbreeding the early clove variety and the late clove variety meeting each other after the regulation is as follows:

(1) After the late clove variety subjected to heating treatment and the early clove variety subjected to cooling treatment enter the initial flowering period, emasculation is continuously carried out on inflorescences to be opened of the early clove variety and the late clove variety for two days, a sulfuric acid paper bag is immediately sleeved after the emasculation, and the temperature control device of the late clove variety is fixed again after the emasculation is finished each time;

(2) After the early clove varieties and the late clove varieties meeting in the later flowering phases are regulated and controlled to enter the full flowering phase, pollen of the early clove varieties and the pollen of the late clove varieties are collected for two consecutive days, pollination is carried out on the pollen for removing male inflorescences, bagging protection is continued after the pollination is finished, and the temperature control device of the late clove varieties is fixed again after the pollen collection and pollination are finished each time;

5. The crossbreeding method for regulating and controlling the flowering period of clove according to claim 4, wherein the temperature control device comprises a temperature control cover with an open bottom, the rear wall of the temperature control cover is a heat insulation cover body, and the front wall, the top wall and the two side walls of the temperature control cover are transparent cover bodies;

a top frame is fixed on the top wall inside the temperature control cover, a square frame is fixed at the lower end part of the temperature control cover, fixing nails are installed at the bottom of the square frame, four oblique frameworks are installed on the top frame and the square frame together, each oblique framework is tightly attached to the inner wall of the temperature control cover, at least one ventilation opening is arranged on the top wall, the front wall, the rear wall and the two side walls of the temperature control cover, a wind-blocking curtain is installed at each ventilation opening through a ventilation opening-closing mechanism, an induction probe is arranged inside the temperature control cover, and the induction probe is connected with a temperature and humidity acquisition instrument;

6. The method as claimed in claim 5, wherein the square frame comprises four bottom frames, every two adjacent bottom frames are perpendicular to each other, a first mounting seat is installed between every two adjacent bottom frames, each bottom frame and each inclined frame are connected with the corresponding first mounting seat and the corresponding top frame through a frame mounting seat assembly, and the fixing nail is fixed at the bottom of each first mounting seat.

7. The crossbreeding method for regulating and controlling the flowering phase of clove according to claim 5, wherein the winding mechanism comprises a pair of oppositely arranged second installation bases, an outer cover body winding roller and a first pressing roller are installed on the two second installation bases together, one end of each of the first outer cover body and the second outer cover body is fixed on the corresponding outer cover body winding roller, the other end of each of the first outer cover body and the second outer cover body bypasses the corresponding first pressing roller, a rotating disc and a holding wheel are fixedly installed at one end of the outer cover body winding roller, a plurality of limiting lugs are arranged on the side wall of the rotating disc, a plurality of limiting grooves are arranged on the corresponding second installation bases, each limiting groove is matched with the limiting lug, and each limiting lug is inserted into one limiting groove.

8. The crossbreeding method for regulating and controlling the flowering phase of clove according to claim 5, wherein the ventilation opening and closing mechanism comprises a wind-shield curtain winding roller arranged below the top frame, a second pressing roller is arranged below the wind-shield curtain winding roller, the second pressing roller extends along the axial direction of the wind-shield curtain winding roller, the second pressing roller and the wind-shield curtain winding roller are hinged to the top frame, a torsion spring is arranged at the hinged position of the wind-shield curtain winding roller and the top frame, the upper end of the wind-shield curtain is fixed on the wind-shield curtain winding roller, the second pressing roller is pressed on the inner wall of the wind-shield curtain, racks are arranged on two sides of the ventilation opening, each rack is perpendicular to the wind-shield curtain roller, a cross rod is fixed at the lower end of the wind-shield curtain, gears are arranged at two ends of the cross rod, each gear is meshed with the corresponding rack, and a handle capable of being used for lifting and pulling the wind-shield curtain is arranged on the outer wall of the wind-shield curtain.