CN107996325B - Method for preventing and controlling sorghum head smut by floating plate seedling culture - Google Patents

Abstract

The invention discloses a method for preventing and controlling the head smut of sorghum by floating plate seedling culture, which comprises the steps of culturing organic sorghum by floating plate seedling culture to prevent and control soil-borne diseases including the head smut of the sorghum; the substrate adopted by the floating plate seedling raising is prepared by mixing 25-35% of decomposed organic fertilizer, 25-35% of ground crust ash and 35-45% of fine fertile soil in percentage by weight; the biogas slurry is used as a nutrient solution in the floating seedling culture of the organic sorghum. The sorghum floating plate seedling raising technology adopted by the invention can be implemented by manufacturing a small arched shed and a nutrition pool by a farmer, is easy to master, simple to operate, convenient to manage and high in success rate, can be used for raising strong seedlings which are not infected by head smut and have developed root systems, and can also be used for greatly shortening the seedling raising time.

Description

Method for preventing and controlling sorghum head smut by floating plate seedling culture

Technical Field

The invention relates to the technical field of crop disease prevention and control, in particular to a method for preventing and controlling sorghum head smut by floating tray seedling.

Background

The sorghum head smut is one of diseases which easily cause serious harm in sorghum production. The disease is widely distributed in sorghum production areas all over the world, and occurs in each sorghum production area in China, the common incidence rate is 3% -5%, and the incidence rate can reach 10% -30% in some years. The disease rate of individual plots is up to more than 80%. At present, the sorghum head smut germ has a new differentiation phenomenon, and has great threat to sorghum production.

Head smut mainly damages sorghum ears, so that the whole ears become black powder, and diseases show obvious symptoms in the booting period of booting ears. The bracts of the diseased spike are compact, the middle and lower parts of the diseased spike are slightly expanded, the diseased spike is hard and solid when pinched by hands, a white rod-shaped object appears when the bracts are stripped, and a white film is arranged on the periphery of the diseased spike. After the rice is ripened, the white film is broken, a large amount of black powder is scattered, and scattered bundled filaments (commonly called black rice) are exposed. After the black rice of the main stalk is beaten off, the tillering ears grown later still form silk black ears. Some diseased ear bases can have a few branches of spikelets, but cannot be firm. Some diseased plant spikes form cluster-shaped diseased leaves, and some form sterile spikes. The diseased plants are usually short and have serious internode shortening, especially internode shortening of the ear-close part.

The pathogenic bacteria of the disease are actinomyces pulcherrima, which belong to the fungi of the actinomycete subgenus actinomyces. The pathogenic bacteria mainly live through winter in soil or on the surface of seeds for about 3 years, and the life of the winter spores can be shortened in rainy and rainy years in summer and autumn. The winter spores scattered on the ground and mixed in the manure are the main infection source of the sorghum head smut; although the bacteria carrying of seeds is less important than the bacteria carrying transmission of soil and manure, the long-distance transmission of the bacteria is an important way.

The sorghum head smut is a seedling system infection disease. After germination, the winter spores directly invade meristem of the young buds, hyphae grow in cells and cells, and develop to apical meristem along with plant growth; after the plants enter the flowering stage, hyphae rapidly grow into spore-producing hyphae, a large amount of winter spores are produced, and the sorghum black rice is formed. The optimal period of infecting sorghum seedlings by pathogenic bacteria is that when white tips are exposed from broken mouths of seeds and sprouts grow to 1-1.5cm, the sprouts are not easy to infect after the height of the sprouts exceeds 1.5 cm. The infection part of the sorghum seedling is mainly mesocotyl, and then coleoptile and radicle, so that the primary infection stage is before the emergence of the sprout. Therefore, the sorghum seeds are prevented from contacting with the soil with bacteria before the sorghum seeds are planted, germinate and emerge to be transplanted, and the infection harm of the sorghum caused by the disease can be greatly controlled.

Disclosure of Invention

The invention aims to provide a method for preventing and controlling the sorghum head smut by using floating plate seedling culture so as to reduce the infection of the sorghum head smut on sorghum seedlings.

The technical scheme of the invention is as follows:

a method for preventing and controlling the head smut of sorghum by using floating plate seedling culture comprises the steps of using a floating plate seedling culture mode to culture organic sorghum to prevent and control partial soil-borne diseases mainly including the head smut of the sorghum; the substrate adopted by the floating plate seedling raising is prepared by mixing 25-35% of decomposed organic fertilizer, 25-35% of ground crust ash and 35-45% of fine fertile soil in percentage by weight; the biogas slurry is used as a nutrient solution in the floating seedling culture of the organic sorghum.

Specifically, the method comprises the following steps:

step 1, selecting a seedbed land: selecting a place which is leeward and exposed to the sun, convenient to traffic, convenient to water source and flat in terrain to build a shed;

step 2, manufacturing a nutrition pool and a small arched shed:

manufacturing a nutrition pool: the nutrition pool is bricked or soil is directly dug out of the soil to be made into a ridge according to a standard box; double-layer polyethylene films are laid inside; adding 0.1m of clear water;

manufacturing a small arched shed: thin bamboo strips are used as an arch frame; after the floating plate is manufactured, inserting a thin bamboo strip arch frame; covering the upper surface with a polyethylene film;

step 3, seedling plate selection and seedling substrate preparation:

seedling raising plate: is made of polystyrene foam plastics;

seedling raising substrate: uniformly mixing 25-35% of decomposed organic fertilizer, 25-35% of ground crust ash and 35-45% of fine fertile soil according to weight percentage, sterilizing by 400 times and 600 times of potassium permanganate solution, and adding a proper amount of water to prepare the fertilizer;

step 4, tray loading and seeding:

and (3) disinfection: sterilizing the seedling raising device with potassium permanganate liquid medicine before seeding, adding 200 times of copper sulfate solution into the nutrition pool after clean water is put in the nutrition pool for sterilization so as to prevent moss from growing in the water pool;

loading a plate: firstly, watering and wetting a seedling raising matrix prepared in advance, and then dishing;

sowing: before transplanting to field, sun-drying selected seeds, soaking in lime water, washing, draining, sowing the seeds into a floating tray filled with a matrix, slightly pressing the surface of the seedling tray with a wood board after sowing the seed tray, so that the seeds are sunk into the seedling substrate, covering the seedling tray with the seedling substrate properly, and then putting the seedling tray into a nutrition pool to float;

fertilizing: the nutrient solution is biogas slurry, and 200 kg of biogas slurry and 300kg of biogas slurry are applied to each standard box; transplanting the seedlings into a field when the seedlings grow to 3-4 leaves and one heart, and then topdressing; the pH value of the nutrient solution is kept between 5 and 7.

Step 5, seedbed management:

enhancing temperature management: the temperature in the greenhouse is kept between 20 and 28 ℃;

step 6, hardening seedlings: transplanting when the sorghum seedlings grow to 3-4 leaves and 1 heart, sequentially uncovering two ends and the film one week before transplanting, moving the floating plate out of the nutrition pool 1-2 days before transplanting, putting the floating plate in outdoor soil, cutting off water and fertilizer, and improving the stress resistance and the transplanting survival rate of the sorghum.

The sorghum floating plate seedling raising technology adopted by the invention can be implemented by manufacturing a small arched shed and a nutrition pool by a farmer, is easy to master, simple to operate, convenient to manage and high in success rate, can be used for raising strong seedlings which are not infected by head smut and have developed root systems, and can also be used for greatly shortening the seedling raising time.

Detailed Description

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Wherein, the related numerical values, parts or proportions are mass numerical values, parts or proportions if not labeled.

The sorghum floating tray seedling culture method is a seedling culture method which comprises the steps of sowing seeds in a foam hole tray provided with seedling culture nutrient soil according to the technical requirements of sorghum production, floating on the water surface, providing light, temperature, water, gas, nutrients and the like required by the growth of sorghum seedlings under the condition of manual control, enabling the seedlings to root and grow in the holes of the floating tray, and absorbing water and nutrients from a substrate and a water pool.

1. Selection of seedbed land:

the shed can be built in a house dam or a garden by selecting a place which is leeward and exposed to the sun, convenient to traffic, convenient to water source and flat in terrain.

2. Manufacturing a nutrition pool and a small arched shed:

manufacturing a nutrition pool: the nutrient pool can be made into a ridge (compacted and can not collapse) by brick laying (the yard dam can be used) or directly digging soil in the soil and making the soil into the standard box. Generally, each nutrition pool (standard box) is 10m long, 1.1m wide, 0.15m deep and 1m of the surrounding walkway. The bottom and side walls of the pool are compacted and leveled, and sharp stones, grass roots and the like cannot be arranged on the pool bottom and the side walls, so that the film is prevented from being scratched. The inner layer is padded with double-layer polyethylene film (thick) to prevent water leakage and preserve heat. If water leaks, the membrane is changed by discharging water instantly.

Manufacturing a small arched shed: the thin bamboo strips (made by bamboo) are manufactured according to the standard of 2.0-2.2m in length and 3-4cm in width and are used as an arch frame, and the thin bamboo strips are required to be smooth and have no sharp protrusions so as to prevent hands and films from being hurt. After the floating plate is manufactured, the thin bamboo strip arch frames are inserted, and only one thin bamboo strip arch frame is inserted every 20-30 cm, the thin bamboo strip arch frames can be inserted alternately, and the firmness is better. Then, a polyethylene film (thickened type) with a width of 2m was covered on the upper surface, and the periphery was tightly bound with soil.

3. Seedling plate selection and nutrient soil preparation:

seedling raising plate: the tray is preferably made of polystyrene foam plastics, is light in weight, can float on the water surface after bearing moisture-absorbing substrates and sorghum seedlings, is resistant to water bubbles and corrosion, has certain mechanical strength, can be used for 3-5 years generally, and can save cost. The floating plate is 0.55cm long and 0.33cm wide, and each plate has 160 holes (or a suitable seedling plate can be selected according to the size of the nutrition pond).

Seedling raising substrate: the seedling substrate, namely the nutrient soil, is a key raw material for floating seedling. The preparation of the nutrient medium comprises the steps of uniformly mixing 30% of decomposed organic fertilizer, 30% of ground crust ash and 40% of fine fertile soil, then sterilizing by 400 times of 600 times of potassium permanganate solution, and adding a proper amount of water.

4. Loading and sowing:

and (3) disinfection: before seeding, the apparatus such as the seedling tray is disinfected by potassium permanganate liquid medicine, and 200ml of 200 times of copper sulfate solution is added into the nutrition pool for disinfection after clean water is put in the nutrition pool, so as to avoid moss growing in the water pool.

Loading a plate: firstly, the nutrient soil prepared in advance is watered and moistened, the moisture of the seedling culture substrate is required to be held by hands to form a ball, the seedling culture substrate is well scattered when the hands are loosened, and the filling is carried out when the seedling culture substrate is placed in a plate, so that the nutrient substrate in the hole is ensured to be naturally filled, is not overhead and is not too tight, and about 2kg of the nutrient substrate is placed in each plate.

Sowing: 15 days before transplanting to field, sun-drying selected seeds for 2 days, soaking in lime water for 2 hours, washing, filtering, sowing 2-3 granules per hole, slightly pressing the surface of seedling tray with wood plate after sowing, making the seeds sink into nutrient soil, covering with nutrient soil, and floating in nutrient pool.

Fertilizing: biogas slurry is applied to the nutrient solution, and 200-300kg of biogas slurry is applied to each standard box of water; if the biogas slurry and special fertilizer are not available, only clear water can be used. When the seedlings grow to 3-4 leaves and one heart, the seedlings are transferred to the field and then are topdressed. The pH of the nutrient solution was checked and maintained between 5 and 7.

5. Seedbed management:

enhancing temperature management: the temperature in the shed is kept between 20 and 28 ℃, if the temperature exceeds 30 ℃, the films at two ends of the arched shed are immediately uncovered for ventilation, and the films are covered and the temperature is preserved in time after 17 pm.

6. Hardening seedlings:

transplanting when sorghum seedlings grow to 3-4 leaves and 1 heart, sequentially uncovering two ends and a film one week before transplanting, moving the floating plate out of the nutrition pool 1-2 days before transplanting, placing the floating plate in outdoor soil for water and fertilizer cutoff, and improving stress resistance and transplanting survival rate of sorghum.

The smut is mainly carried by seeds and soil and is infected by a seedling system, so that the smut is prevented and treated by selecting a disease-resistant variety, changing various crops in the field, reversing stubble and the like, the disease is reduced, more importantly, the seeds are disinfected, the seeds are prevented from contacting with the bacterium-carrying soil in the seedling stage to cut off the propagation path, the infection of germs is controlled from the source, and the occurrence of the smut is effectively controlled.

The seed disinfection can be carried out by adopting 1 percent lime water, copper sulfate, biological agents and the like, and can also be carried out by sunning, the problems that germs are killed by sunlight ultraviolet rays and the like are solved, but the infection of sorghum seedlings caused by soil-borne bacteria is difficult to control, the soil disinfection area is too large, the operation is difficult, the cost is too high, and the operability is not strong. If the sorghum does not contact with soil in the seedling stage, the propagation path can be effectively cut off. Therefore, floating seedling can solve the problem well. The test and survey data of years show that the floating seedling culture can well prevent and control the occurrence of the smut.

Relevant experimental data and investigation conditions:

in 2014-2016, the floating-tray seedling transplantation and the black ear disease investigation are carried out in the Tan factory town loquat village, Luban town Longbao village, landscape village, Mao dam town Shiliang village, guan court village, favorite town center village and the like, and the conditions are as follows:

(I) test of influence of different sorghum seedling raising modes on smut

In recent years, smut is in a high incidence trend, a special test of the influence of different sorghum seedling raising modes on smut is developed for effectively controlling the occurrence of the smut of sorghum, and a theoretical basis is provided for the prevention and control of the smut. The test was carried out in the Luban Tanshima in 2014 on the preference of the Mao dam in the Luban Tanshima, and the test summary is as follows:

1. materials and methods

1.1 site of execution

Luban town mountain and river village, Tan factory loquat village, Mao dam officer village, and Xitou center village. The test field area is more than 1 mu, the rape is previously used, and the soil fertility is moderate.

1.2 design of the experiment

Let 3 treatments:

a: floating seedling (160-hole nutrition plate) B: and (4) seedling raising of nutrient blocks C: broadcast sowing and seedling (CK)

The blocks are randomly arranged and repeated for three times, and the area of a cell is 20 square meters.

1.3 test materials

Red tassel seed sorghum, polystyrene nutrition float dish (160 holes)

2. Execution of the test

2.1 sowing time:

loquat in jar factory: sowing for 4 months and 1 day, sowing for 4 months and 2 days, and floating for 4 months and 15 days;

lubanlong castle: broadcasting for 4 months and 3 days, sowing for 4 months and 4 days, and floating for 4 months and 16 days;

the dam officer: sowing for 4 months and 5 days, floating for 4 months and 17 days;

the head preference center: broadcast for 4 months and 6 days, nutrient block for 4 months and 6 days, and floating for 4 months and 17 days.

2.2 transplanting time:

transplanting in 29-5 months and 5 days in 4 months.

2.3 the specific preparation method of each treatment comprises the following steps:

2.3.1 raising seedlings by using nutrient blocks: fertilizing a seedbed 10d by applying 10kg of organic fertilizer and 750kg of clear excrement water per mu, cutting the fertilized seedbed land into thin pieces, ditching to form a box, wherein the box width is 4 feet, the ditch width is 1 foot, and the ditch depth is 0.5 foot, growing seedlings by using nutrient blocks, spreading 5-6 cm of nutrient soil on the seedbed, scraping and compacting, cutting into 1.5-2 inch square nutrient blocks by using a wood board and a knife, sowing 2-3 seeds in each nutrient block, and covering with 1 cm of fine soil. And covering a plastic film on the seedbed to preserve fertilizer and water. After the sorghum seedlings emerge, the seedlings are homogenized in time, and before transplanting, the films are removed in time according to the climate to harden the seedlings.

2.3.2 broadcast sowing and seedling raising: after fine preparation of sandy loam, 0.2kg of organic fertilizer and 75kg of excrement cleaning water are applied to every 10 square meters, 33 g of seeds are applied to every 10 square meters, the seeds are uniformly sown on a seedbed, the seeds are planted for 2-3 leaves, the spacing between the seeds is 3.3cm, and other management is the same as that of a nutrition block.

2.3.3 float seedling: selecting a 160-hole polystyrene foam disc, disinfecting the disc by potassium permanganate, then loading a substrate fertilizer, loading about 2kg of seeds in each disc, sowing 2-3 seeds in each hole, slightly pressing the surface of the seedling disc by a wood board after sowing to achieve flattening of the seedling disc, leading the seeds to be sunk into a nutrient soil substrate, properly covering the disc by the substrate, then putting the disc into a nutrient pond to float, and applying 200 kg of biogas slurry and 300kg of fertilizer in each standard box. The temperature in the seedling shed is controlled at 20-28 ℃, and the temperature in the shed is not more than 35 ℃.2 leaves and 1 heart time thinning, and 2 plants are remained in each hole. And (5) starting to uncover the membrane and hardening seedlings 1 week before transplanting.

2.4 transplanting and field management: seedlings of the three seedling raising modes can be lifted and transplanted when growing to 4-5 leaves, the transplanting specification net work sorghum row spacing is 60cm, the nest spacing is 27cm, the nest digging transplanting is carried out, 2 seedlings are planted in each nest, and the density per mu is 8000. 1000kg of manure and 40kg of organic fertilizer (N + P2O5+ K2O is more than or equal to 5.0 percent, and organic matter is more than or equal to 30 percent) are applied to each mu during transplanting. After transplanting survival, seedling checking and seedling supplementing are combined, 1000kg of clear excrement water is applied for one-time living fertilizer per mu, 1000kg of clear excrement water is applied for one month after transplanting, intertillage weeding is combined, and sorghum is harvested at proper time after being mature.

3. Results and analysis

3.1 occurrence of smut (see tables 1 and 2)

TABLE 1 incidence of smut at different test points

TABLE 2 comprehensive analysis of smut occurrence at four test points

As can be seen from the above table 1, the incidence of smut is below 2% when sorghum is planted in floating seedling raising modes at different test points; sorghum is planted in a nutrient block seedling raising mode, and the incidence rate of smut is about 4 percent; sorghum is planted in a broadcast sowing seedling raising mode, and the incidence rate of smut is about 5%. As can be seen from Table 2, the incidence of smut is highest in sorghum planted in the broadcast seedling mode, and then the seedling is grown in a nutritive block, and the seedling is grown in a floating mode.

(II) 2015 field survey of smut occurrence

In 2015, the organic agriculture development center in ren Huai city arranged the survey of the occurrence of black smut in organic sorghum plots (see table 4). According to the summary result, as shown in table 3, the incidence rate of smut is high, 11.4%, while the broadcast seedling method is relatively light, but 5.3%, while the floating seedling method is the lightest, only 1.4%. The floating seedling raising can effectively prevent the sorghum smut.

Table 3.2015 summary of smut occurrence in field survey of ren Huai city

Seedling raising method	Mean incidence of disease
		Live broadcast	11.4
Broadcast sowing	5.3
		Float	1.4

Table 4.2015 Renhuai field investigation of smut occurrence

(III) 2016 field survey on smut occurrence

In 2016, the organic agriculture development center in Renheyi city arranged the survey of the occurrence of smut in organic sorghum plots again (see Table 6). According to the summary result, as shown in table 5, when sorghum is planted in a direct seeding mode, the incidence rate of smut is high and reaches 11.3%, the incidence rate of a broadcast seeding mode is 5.2%, and the incidence rate of a floating seeding mode is only 1.2%. The floating seedling raising can effectively prevent the sorghum smut.

Table 5.2016 summary of smut occurrence in field survey of ren Huai city

Seedling raising method	Mean incidence of disease
		Live broadcast	11.3
Broadcast sowing	5.2
		Float	1.2

Table 6.2016 Renhuai field investigation of smut occurrence

Tests and survey data of two continuous years show that the incidence of the sorghum smut can be completely controlled within 2% by adopting a floating seedling raising mode, the incidence of the sorghum smut is reduced by 9% compared with that of the sorghum smut planted conventionally by more than 11%, and the method has obvious effect of ensuring the quality and the yield of the sorghum. Meanwhile, tests show that the floating seedling raising mode has a good control effect on other soil-borne diseases.

Of course, the above is only a specific application example of the present invention, and other embodiments of the present invention are also within the scope of the present invention.

Claims (1)

1. A method for preventing and controlling the head smut of sorghum by using floating plate seedling culture is characterized in that: seedling raising is carried out on the organic sorghum by adopting a floating tray seedling raising mode so as to prevent and control partial soil-borne diseases mainly including head smut of the sorghum; the substrate adopted by the floating plate seedling raising is prepared by mixing 25-35% of decomposed organic fertilizer, 25-35% of ground crust ash and 35-45% of fine fertile soil in percentage by weight; the biogas slurry is used as a nutrient solution in the floating seedling culture of the organic sorghum; the method comprises the following steps:

step 1, selecting a seedbed land: selecting a place which is leeward and exposed to the sun, convenient to traffic, convenient to water source and flat in terrain to build a shed;

step 2, manufacturing a nutrition pool and a small arched shed:

manufacturing a nutrition pool: the nutrition pool is bricked or soil is directly dug out of the soil to be made into a ridge according to a standard box; double-layer polyethylene films are laid inside; adding 0.1m of deep clear water;

manufacturing a small arched shed: thin bamboo strips are used as an arch frame; after the floating plate is manufactured, inserting a thin bamboo strip arch frame; covering the upper surface with a polyethylene film;

step 3, seedling plate selection and seedling substrate preparation:

seedling raising plate: is made of polystyrene foam plastics;

seedling raising substrate: uniformly mixing 25-35% of decomposed organic fertilizer, 25-35% of ground crust ash and 35-45% of fine fertile soil according to weight percentage, sterilizing by 400 times and 600 times of potassium permanganate solution, and adding a proper amount of water to prepare the fertilizer;

step 4, tray loading and seeding:

and (3) disinfection: sterilizing the seedling raising device with potassium permanganate liquid medicine before seeding, adding 200 times of copper sulfate solution into the nutrition pool after clean water is put in the nutrition pool for sterilization so as to prevent moss from growing in the water pool;

loading a plate: firstly, watering and wetting a seedling raising matrix prepared in advance, and then dishing;

sowing: after selected seeds are planted in the sun, the seeds are soaked by lime water and washed clean and drained, the seeds are sowed in a floating tray filled with a matrix, the surface of the seedling tray is lightly pressed by a wood board after the sowing of the seed tray is finished, the seeds are sunk into a seedling raising matrix, the seedling tray is placed in a nutrition pool to float after being properly covered by the seedling raising matrix;

fertilizing: the nutrient solution is biogas slurry, and 200-300kg of biogas slurry is applied to each standard tank of water; transplanting the seedlings into a field when the seedlings grow to 3-4 leaves and one heart, and then topdressing; the pH value of the nutrient solution is kept between 5 and 7;

step 5, seedbed management:

enhancing temperature management: the temperature in the greenhouse is kept between 20 and 28 ℃;

step 6, hardening seedlings: transplanting when the sorghum seedlings grow to 3-4 leaves and 1 heart, sequentially uncovering two ends and the film one week before transplanting, moving the floating plate out of the nutrition pool 1-2 days before transplanting, putting the floating plate in outdoor soil, cutting off water and fertilizer, and improving the stress resistance and the transplanting survival rate of the sorghum.