CN113854080A - Planting method of selenium-rich purple yam - Google Patents

Abstract

The invention discloses a planting method of selenium-rich purple yam. Belongs to the technical field of planting of taros. The method comprises the following steps of selecting planting sites of the purple yams, selecting varieties, growing seedlings of the purple yams, planting, fertilizing, weeding, earthing up, managing water, preventing and treating plant diseases and insect pests and the like, taking good varieties as seeds, realizing management from the seedling growing of the varieties to the maturity of the purple yams, only spraying for many times in the process of enriching the selenium of the purple yams to enrich the selenium of the purple yams, wherein the selenium content of the harvested purple yams is more than 20 mu g/kg; the Chinese yam reaches the selenium-rich product standard by spraying the foliar selenium fertilizer, and the technical problems of high production cost and complex operation caused by the fact that a large amount of selenium fertilizer needs to be applied in the land in the traditional method for absorbing selenium element from the land and enriching the selenium by the selenium-rich purple yam are solved.

Description

Planting method of selenium-rich purple yam

Technical Field

The invention relates to the technical field of planting of purple yams, in particular to a planting method of selenium-rich purple yams.

Background

A perennial herbaceous plant of Konjac of Leguminosae is cultivated annually. The taro is nutritious. The staple food part of the taro is a bulb, the petiole can be used for pickling taro lotus and can be used as green feed and the like, the bulb has less fiber, the starch content is high, the edible sand is fragrant, the taste is delicious, and the taro is deeply loved by consumers.

Selenium is one of indispensable trace elements in human life, medical data shows that selenium is an important component of antioxidant enzyme and selenium-P protein in animals and human bodies, plays a role in balancing oxidation reduction in vivo, has the functions of prevention and adjuvant therapy on various diseases of human bodies, can enhance the immunologic function of human bodies, has the functions of cancer prevention and cancer resistance, can also play a good role in prevention and treatment of diabetes, Kaschin-Beck disease, asthma, Parkinson's disease, cardiovascular and cerebrovascular diseases and the like, and can also cause various eye diseases due to selenium deficiency. Selenium supplement is the best measure for preventing cancers, but the selenium is not easy to be absorbed by human bodies when being taken directly, and the best selenium supplement measure is to take the selenium from food to achieve the purpose of selenium supplement.

Therefore, the planting method capable of enriching the selenium of the purple yam is urgently needed to be provided, so that the purple yam is enriched in the selenium, and the purple yam planting method has higher health-care significance and economic value. In the traditional selenium-rich purple yam planting method, the selenium element is required to be rich in the land, so that the purple yam can absorb the selenium element from the land, and the selenium-rich effect is realized. Thus, the requirement of selenium enrichment in the land requires applying a large amount of selenium fertilizer in the land, which causes high production cost and complex operation.

Disclosure of Invention

The invention aims to solve the problems, and provides a planting method of selenium-rich purple yam, which enables the Chinese yam to reach the standard of a selenium-rich product by spraying a foliar selenium fertilizer, and solves the technical problems of high production cost and complex operation caused by the fact that a large amount of selenium fertilizer is applied to the land when the selenium element is absorbed by the traditional selenium-rich purple yam from the land.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a planting method of selenium-rich purple yam is characterized by comprising the following steps: comprises the following steps

Step S1 planting site selection: it is suitable for paddy fields;

step S2 taro variety: selecting Arecae semen of Quercus of Araceae, HEZHOU rhizoma Steudnerae;

step S3 seedling raising of taro:

selecting seed taros which have strong terminal buds, no disease spot worm mouths and good corm shapes from disease-free mother plants as seed taros, selecting single seed taros of 40-50 g as seeds, and using the seed amount of 80-100 kg per mu; soaking the seeds of the taros in disinfectant for about 30 minutes, and airing and raising seedlings; selecting field blocks which are leeward and exposed to the sun, convenient to drain, fertile and loose in soil and flat in pH value of 5.5-7.0 in the seedling culture land, and applying a seedbed fertilizer after sterilizing before sowing; seedling is cultivated by adopting a reverse planting method, and the seedlings can be transplanted to a field when the height of the seedlings is 10-15 cm and 1 leaf and 1 heart are obtained;

step S4 taro planting:

planting taro fields by using loam or sandy loam with deep, loose and fertile soil layers and a plough layer of more than 30cm, wherein the pH value of the soil is 5.5-7.0; planting in 3 late ten days to 4 middle ten days, when the temperature reaches above 15 ℃, planting in sunny days, and pouring root fixing water in time after planting;

step S5 taro fertilization: starting the first topdressing when the height of the seedling is 35-40cm, and applying for 2-3 times per month; starting secondary topdressing when the height of the taro seedlings is 50-55 cm; when the line is sealed in 6-7 months for the third time of topdressing, topdressing is carried out in combination with the taro earthing up and furrow application; topdressing is carried out for the last time before and after sunstroke, and seedling strengthening fertilizer is used for spraying roots once every 6-7 days for 3 times continuously, so as to achieve the purposes of inhibiting stem and leaf overgrowth and promoting corm expansion;

step S6 selenium fertilizer is applied to the purple yam: applying selenium fertilizer in the expansion period of the corms of the taros for 8-10 months, spraying 1500 times of solution of the selenium fertilizer 1000 times in a leaf surface spraying manner for 3 times, wherein the application amount is 100 ml/mu, and the interval of each time is 7-10 days;

step S7 weeding and ridging the taro: artificial weeding is carried out to prevent the growth of weeds; cultivating and hilling the henry steudnera tuber for 3 times, wherein the 1 st time is in a leaf stage of 3-4, the 2 nd time is in a leaf stage of 6-7, and the 3 rd time is in a leaf stage of 9-10;

step S8 taro water management: the soil of the taro at the early growth stage needs to be kept moist, and sufficient water needs to be supplied during the full growth period and the bulb forming period;

step S9 pest control of taro: adopting one or more of agricultural control, biological control, physical control and chemical control to carry out pest and disease control on the taro;

step S10 picking and storing the purple yam: collecting and storing the mother taro.

Further, in step S3, the disinfectant is a 1000-fold liquid of carbendazim wettable powder, a 1000-fold liquid of 70% thiophanate methyl wettable powder, or a 1500-fold liquid of 1000-fold 50% phoxim emulsifiable concentrate.

Further, in step S3, the method includes disinfecting the bed soil with quicklime, applying a bed fertilizer after land preparation, applying 550kg of decomposed farmyard manure per mu of bed soil, and mixing the farmyard manure with the bed soil sufficiently.

Further, in step S3, the inverted planting method is that the top end of the seed taro is placed at the bottom of the soil, the tail end of the seed taro inclines towards 45 degrees, the distance between the taros is 5-10cm, then a layer of sandy soil is laid to fill and fix the seed taro, a thin layer of plant ash is covered on the seed taro, the thickness of the plant ash is not enough to expose the seed taro, then a layer of straw is covered on the seedbed, and a plastic film is covered on the seedbed; keeping the water content of the soil at 50-70%, and turning over the plastic film when the air temperature reaches above 15 ℃; the seedlings with thick and strong bud heads, snow white, regular germination, thick and short root systems, no disease spot and no leaf exposure can be used for planting.

Further, in step S4, 1700-year 2000 plants are field-planted per mu, and single-row field planting or double-row field planting is carried out, wherein the requirements on the quality, the thickness and the size of the henry steudnera seedlings during field planting are basically uniform.

Further, in step S5, the first topdressing is to apply 700-900 kg of 25-35% human excrement and urine fertilizer and 25-50 kg of potassium nitrate per mu; the second topdressing is to apply 50-60 kg of ternary compound fertilizer per mu; the third topdressing is 1500-2000 kg of decomposed organic manure and 60-70 kg of ternary compound fertilizer; the last topdressing is to apply 60-70 kg of imported compound fertilizer, 15-17 kg of biological potassium and 15-17 kg of biological phosphorus in each mu of hole.

Further, the content ratio of the ternary compound fertilizer is as follows: n: p₂O₅：K₂O＝15：15：15。

Further, in step S8, the water management of the taro is specifically to keep the soil moist in the early and middle period; after a sunstroke, a deep water layer of about 12-16cm is required to be kept in the ditch frequently, and the surface of the ridge is not flooded by water; after 8 ten days in the middle of the month, keeping the furrow water dry to increase the soil humidity, reduce the soil temperature and improve the field microclimate; after frost had passed, the bulbs had matured and water was drained 15 days before harvest.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

1. the method realizes the management from the seedling cultivation of the variety to the ripening of the purple yam by selecting the planting site of the purple yam, selecting the variety, cultivating the seedling of the purple yam, applying fertilizer, weeding, earthing up, managing water, preventing and controlling plant diseases and insect pests and the like by taking the excellent variety as the seed, and only adopting a spraying mode for many times in the process of enriching the selenium of the purple yam to enrich the selenium, wherein the selenium content of the harvested purple yam is more than 20 mug/kg; the Chinese yam reaches the selenium-rich product standard by spraying the foliar selenium fertilizer, and the technical problems of high production cost and complex operation caused by the fact that a large amount of selenium fertilizer is applied to the land when the traditional selenium-rich taro absorbs selenium from the land are solved.

Detailed Description

Example 1

A planting method of selenium-rich purple yam is characterized by comprising the following steps: comprises the following steps

Step S1 planting site selection: it is suitable for paddy fields;

step S2 taro variety: selecting Arecae semen of Quercus of Araceae, HEZHOU rhizoma Steudnerae;

step S3 seedling raising of taro:

selecting young taros which have strong terminal buds, no disease spot worm mouths and good corm shapes and have purplish red areca-nut patterns from disease-free mother plants as seed taros, selecting single 40 g of young taros as seeds, and using the seed amount of 80 kg per mu; soaking the seeds of the taros in disinfectant for about 30 minutes, and airing and raising seedlings; selecting field blocks which are leeward and exposed to the sun, convenient to drain, fertile and loose in soil and 5.5 flat in pH value from the seedling culture land, and applying a seedbed fertilizer after sterilizing before sowing; adopting an inverted planting method to grow seedlings, and transplanting the seedlings to a field when the height of the seedlings is 10cm and 1 leaf is 1 heart;

specifically, the disinfectant is 1000 times of carbendazim wettable powder; the method comprises the steps of disinfecting seedbed soil with quicklime in the seedling growing land, applying seedbed fertilizer after land preparation, applying 450kg of decomposed farmyard manure to each mu of seedbed, and fully mixing the farmyard manure with the seedbed soil.

The method comprises the steps of placing the top end of each taro seed at the bottom of soil, inclining the tail end of each taro seed at an angle of 45 degrees, keeping the distance between the taros at 5cm, paving a layer of sandy soil to fill and fix the taros, covering a thin layer of plant ash on each taro seed to a thickness which does not expose the taro seed, covering a layer of straw on a seedbed, and covering a plastic film; keeping the water content of the soil at 50-70%, and turning over the plastic film when the air temperature reaches above 15 ℃; the seedlings with thick and strong bud heads, snow white, regular germination, thick and short root systems, no disease spot and no leaf exposure can be used for planting.

Step S4 taro planting:

planting taro fields by using loam or sandy loam with deep, loose and fertile soil layers and a plough layer of more than 30cm, wherein the pH value of the soil is 5.5; the planting time is 3 last ten days, when the temperature reaches above 15 ℃, planting is carried out on sunny days, and the root fixing water is sprayed in time after planting. 1700-plants are planted in each mu, and the seedlings are planted in a single row or double rows, and the requirements on the quality, the thickness and the size of the purple yam seedlings during planting are basically uniform.

Step S5 taro fertilization: starting the first topdressing when the height of the seedling is 35cm, and applying for 2 times per month; starting secondary topdressing when the height of the taro seedlings is 50 cm; when the line is sealed in 6-7 months for the third time of topdressing, topdressing is carried out in combination with the taro earthing up and furrow application; topdressing is carried out for the last time before and after sunstroke, and seedling strengthening fertilizer is used for spraying roots once every 6 days for 3 times continuously, so as to achieve the purposes of inhibiting stem and leaf overgrowth and promoting corm expansion; specifically, the first topdressing is to apply 700 kg of 25% human excrement and urine fertilizer and 25 kg of potassium nitrate per mu; the second topdressing is to apply 50kg of ternary compound fertilizer per mu; 1500 kilograms of decomposed organic manure and 60 kilograms of ternary compound fertilizer are applied in the third topdressing; and the last topdressing is to apply 60 kg of imported compound fertilizer, 15 kg of biological potassium and 15 kg of biological phosphorus in each mu of hole. The content ratio of the ternary compound fertilizer is as follows: n: P2O 5: K2O ═ 15: 15: 15.

step S6 selenium fertilizer is applied to the purple yam: applying selenium fertilizer in the corm expansion period of the taros within 8-10 months, spraying 1000 times of selenium fertilizer liquid in a leaf surface spraying mode for 3 times, wherein the application amount is 100 ml/mu, and the interval of each time is 7 days; in this embodiment, the selenium fertilizer is a selenium carefree selenium fertilizer that is available on the market.

Step S7 weeding and ridging the taro: artificial weeding is carried out to prevent weeds from growing, and the weeding is to prevent the bulbs from being damaged and avoid using herbicides; cultivating and hilling the henry steudnera tuber for 3 times, wherein the 1 st time is in a leaf stage of 3-4, the 2 nd time is in a leaf stage of 6-7, and the 3 rd time is in a leaf stage of 9-10; the intertillage and hilling can be carried out by combining weeding and fertilization.

Step S8 taro water management: the soil of the taro at the early growth stage needs to be kept moist, and sufficient water needs to be supplied during the full growth period and the bulb forming period; the water management of the taro is specifically realized by keeping soil moist in the early and middle periods; after a sunstroke, a deep water layer of about 12-16cm is required to be kept in the ditch frequently, and the surface of the ridge is not flooded by water; after 8 ten days in the middle of the month, keeping the furrow water dry to increase the soil humidity, reduce the soil temperature and improve the field microclimate; after frost had passed, the bulbs had matured and water was drained 15 days before harvest.

Step S9 pest control of taro: adopting one or more of agricultural control, biological control, physical control and chemical control to carry out pest and disease control on the taro;

specifically, agricultural control: selecting disease-free seed taro or virus-free seed taro, soaking seed with insecticidal sterilizing liquid for sterilization, and transplanting seedlings with medicine. Biocontrol execution SN/T2118-2008 "guide for introduction of natural enemies and management of biocontrol", introduction of release of natural enemies and management of biocontrol. Biological pesticides such as matrine, abamectin, kasugamycin, agricultural streptomycin and the like, insect pheromones such as a prodenia litura sex attractant and the like, insecticidal plants such as tea seed cake, tobacco and the like, and mineral pesticides such as Bordeaux mixture and the like are selected to combine treatment by picking, common treatment and grass generation, so that natural enemies are protected and utilized. Physical control: the prodenia litura, scarab and the like are trapped and killed by a frequency vibration type insecticidal lamp. Manually killing mole crickets and removing egg masses such as prodenia litura and the like in a pest concentration area and an insect egg concentration area under a lamp. Chemical control: taro epidemic disease is prevented and treated by spraying 25 percent of wettable powder of Jiashuang Cu 600 times liquid, 64 percent of wettable powder of arsenopyrite 500 times liquid, 25 percent of clotrimazole 1000 times liquid, wettable powder of arsenopyrite 500 times liquid and 58 percent of wettable powder of Redox manganese-zinc 500 times liquid in the early stage of disease incidence, and the taro epidemic disease is sprayed for 1 time every 7 to 10 days and is sprayed for 3 to 4 times continuously. And (3) preventing soft rot of taro, namely preventing taro from soft rot in late 6 to 8 months, wherein the pesticide can be sprayed with 3000 times of 72% agricultural streptomycin wettable powder and 400 times of 25% cuaminosulfate aqueous solution, or sprayed with 1:1:100 Bordeaux solution or sprayed on roots for preventing taro soft rot, and the taro soft rot is sprayed for 1 time at intervals of 7 to 10 days and for 2 to 3 times continuously. When the disease is controlled, underground pests need to be controlled, so that the wound of the taro is reduced, and the infection of germs is relieved. The medicament can be poured by using 400 times of 18 percent bisultap solution. Taro diricht spot is controlled by spraying 500 times of 50% thiophanate methyl wettable powder and 600 times of 75% chlorothalonil wettable powder. It is administered once every 7-8 days for 2-3 times. 4.4 Spodoptera litura uses the following medicaments: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. 4.5 preventing and treating taro and single-thread hawkmoth in the middle and late 6 months by spraying 48% Lespede1500 times liquid, 800-1000 times liquid of BT powder and 1000 times liquid of 1.8% abamectin. 4.6 aphids can be prevented and treated by spraying 10 percent imidacloprid 4000-fold liquid and 10 percent high-power minister 4000-fold liquid from the first ten days of 5 months to the last ten days of 10 months. The spodoptera litura, wherein the spotter generation stage is performed before 3 instars of larvae, picking and controlling are performed by combining with a field pipe, and the larvae move out at night after 4 instars, and are sprayed before and after evening or sprayed together with the ground and the base of the taro plant during spraying. The used medicaments comprise: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. The taro caterpillar and the single-thread hawkmoth can be prevented and treated in the middle ten days of 6 months to the late ten days of 9 months by spraying 48 percent of Lesbane 1500-fold liquid, 800-1000-fold liquid of BT powder and 1000-fold liquid of 1.8 percent of abamectin. The aphid can be sprayed and prevented by 10 percent of imidacloprid 4000-times liquid and 10 percent of Chinese minister 4000-times liquid from the first ten days of 5 months to the last ten days of 10 months.

Step S10 picking and storing the purple yam: collecting and storing the mother taro.

Specifically, the taro leaves turn yellow and can be harvested, harvesting time can be arranged according to market conditions, and harvesting can be performed in the middle of 11 months to 2 months later. The ditch water must be drained 15-20 days before harvesting, so as to be beneficial to full conversion of nutrients and improve the quality. The harvesting should be carried out in sunny days, the whole plant is dug up, the water is dried in the air, the residual leaves and fibrous roots are removed, and the plant can be stored. And (4) harvesting healthy seed taros, storing the seeds in a classified mode, and planting the seeds in the next year. Or after the mother taro is harvested, the robust son taro is left in the field to overwinter, and the next year is harvested, sowed and cultured or self-growing seedlings are cultivated. The storing place of the yam is selected from a sandy field which is ventilated, exposed to the sun and good in drainage and is not planted with the betel nut yam in the current year. And digging a 30-40 cm-deep surrounding ditch around the storage land as a drainage ditch, and leveling the storage land for later use. After the mother taro is pulled up from the taro field, the stem of the taro is cut off, the mother taro is inverted and vertically arranged on the storage ground one by one, and the periphery and the upper part of the mother taro are covered with 10-20 cm layers of native people. The storage of the mother taro is finished in the same day after the mother taro is pulled from the taro field. The water content of soil in the storage land must be kept at 60-70%, the soil is sprayed with water for moisture preservation after being dried, and when the temperature is reduced to 5 ℃, the storage land is covered with sundries such as straws or covered with a plastic film for moisture preservation, and the snow water infiltration is strictly prevented.

Example 2

A planting method of selenium-rich purple yam is characterized by comprising the following steps: comprises the following steps

Step S1 planting site selection: it is suitable for paddy fields;

step S2 taro variety: selecting Arecae semen of Quercus of Araceae, HEZHOU rhizoma Steudnerae;

step S3 seedling raising of taro:

selecting young taros which have strong terminal buds, no disease spot worm mouths and good corm shapes and have purplish red areca-nut patterns from disease-free mother plants as seed taros, selecting single 45 g of seed taros as seeds, and using the seed amount of 90 kg per mu; soaking the seeds of the taros in disinfectant for about 30 minutes, and airing and raising seedlings; selecting field blocks which are leeward and exposed to the sun, convenient to drain, fertile and loose in soil and flat in pH value of 6.3 in the seedling culture land, and applying a seedbed fertilizer after sterilizing before sowing; adopting an inverted planting method to grow seedlings, and transplanting the seedlings to a field when the height of the seedlings is 13cm and 1 leaf is 1 heart;

specifically, the disinfectant is 1000 times of 70% thiophanate methyl wettable powder; the method comprises the steps of disinfecting seedbed soil with quicklime in the seedling growing land, applying seedbed fertilizer after land preparation, applying about 500kg of decomposed farmyard manure to each mu of seedbed, and fully mixing the farmyard manure with the seedbed soil.

The method comprises the steps of placing the top end of each taro seed at the bottom of soil, inclining the tail end of each taro seed at an angle of 45 degrees, enabling the taro seed to be 8cm apart, then paving a layer of sandy soil to fill and fix the taro seed, covering a thin layer of plant ash on the taro seed to a thickness which does not expose the taro seed, covering a layer of straw on a seedbed, and covering a plastic film; the water content of the soil is kept at 60 percent, and the plastic film is turned over when the air temperature reaches above 15 ℃; the seedlings with thick and strong bud heads, snow white, regular germination, thick and short root systems, no disease spot and no leaf exposure can be used for planting.

Step S4 taro planting:

planting taro fields by using loam or sandy loam with deep, loose and fertile soil layers and a plough layer of more than 30cm, wherein the pH value of the soil is 6.3; the planting time is ten days before 4 months, when the temperature reaches above 15 ℃, planting is carried out on sunny days, and the root fixing water is sprayed in time after planting. 1850 plants are planted in each mu, and the seedlings are planted in single row or double rows, and the requirements on the quality, the thickness and the size of the purple yam seedlings during planting are basically uniform.

Step S5 taro fertilization: starting the first topdressing when the height of the seedling is 35-40cm, and applying for 2-3 times per month; starting secondary topdressing when the height of the taro seedlings is 50-55 cm; when the line is sealed in 6-7 months for the third time of topdressing, topdressing is carried out in combination with the taro earthing up and furrow application; topdressing is carried out for the last time before and after sunstroke, and seedling strengthening fertilizer is used for spraying roots once every 6-7 days for 3 times continuously, so as to achieve the purposes of inhibiting stem and leaf overgrowth and promoting corm expansion; specifically, the first topdressing is to apply 800 kg of 30% human excrement and urine fertilizer and 40 kg of potassium nitrate per mu; the second topdressing is to apply 55 kg of ternary compound fertilizer per mu; 1750 kg of decomposed organic manure and 65 kg of ternary compound fertilizer are applied in the third topdressing; and the last topdressing is to apply 65 kg of imported compound fertilizer, 16 kg of biological potassium and 16 kg of biological phosphorus in each mu of hole. The content ratio of the ternary compound fertilizer is as follows: n: P2O 5: K2O ═ 15: 15: 15.

step S6 selenium fertilizer is applied to the purple yam: applying selenium fertilizer in the expansion period of the corms of the taros for 8-10 months, spraying 1500 times of solution of the selenium fertilizer 1000 times in a leaf surface spraying manner for 3 times, wherein the application amount is 100 ml/mu, and the interval of each time is 7-10 days; in this embodiment, the selenium fertilizer is a selenium carefree selenium fertilizer that is available on the market.

Step S7 weeding and ridging the taro: artificial weeding is carried out to prevent weeds from growing, and the weeding is to prevent the bulbs from being damaged and avoid using herbicides; cultivating and hilling the henry steudnera tuber for 3 times, wherein the 1 st time is in a leaf stage of 3-4, the 2 nd time is in a leaf stage of 6-7, and the 3 rd time is in a leaf stage of 9-10; the intertillage and hilling can be carried out by combining weeding and fertilization.

Step S8 taro water management: the soil of the taro at the early growth stage needs to be kept moist, and sufficient water needs to be supplied during the full growth period and the bulb forming period; the water management of the taro is specifically realized by keeping soil moist in the early and middle periods; after a sunstroke, a deep water layer of about 12-16cm is required to be kept in the ditch frequently, and the surface of the ridge is not flooded by water; after 8 ten days in the middle of the month, keeping the furrow water dry to increase the soil humidity, reduce the soil temperature and improve the field microclimate; after frost had passed, the bulbs had matured and water was drained 15 days before harvest.

Step S9 pest control of taro: adopting one or more of agricultural control, biological control, physical control and chemical control to carry out pest and disease control on the taro;

specifically, agricultural control: selecting disease-free seed taro or virus-free seed taro, soaking seed with insecticidal sterilizing liquid for sterilization, and transplanting seedlings with medicine. Biocontrol execution SN/T2118-2008 "guide for introduction of natural enemies and management of biocontrol", introduction of release of natural enemies and management of biocontrol. Biological pesticides such as matrine, abamectin, kasugamycin, agricultural streptomycin and the like, insect pheromones such as a prodenia litura sex attractant and the like, insecticidal plants such as tea seed cake, tobacco and the like, and mineral pesticides such as Bordeaux mixture and the like are selected to combine treatment by picking, common treatment and grass generation, so that natural enemies are protected and utilized. Physical control: the prodenia litura, scarab and the like are trapped and killed by a frequency vibration type insecticidal lamp. Manually killing mole crickets and removing egg masses such as prodenia litura and the like in a pest concentration area and an insect egg concentration area under a lamp. Chemical control: taro epidemic disease is prevented and treated by spraying 25 percent of wettable powder of Jiashuang Cu 600 times liquid, 64 percent of wettable powder of arsenopyrite 500 times liquid, 25 percent of clotrimazole 1000 times liquid, wettable powder of arsenopyrite 500 times liquid and 58 percent of wettable powder of Redox manganese-zinc 500 times liquid in the early stage of disease incidence, and the taro epidemic disease is sprayed for 1 time every 7 to 10 days and is sprayed for 3 to 4 times continuously. And (3) preventing soft rot of taro, namely preventing taro from soft rot in late 6 to 8 months, wherein the pesticide can be sprayed with 3000 times of 72% agricultural streptomycin wettable powder and 400 times of 25% cuaminosulfate aqueous solution, or sprayed with 1:1:100 Bordeaux solution or sprayed on roots for preventing taro soft rot, and the taro soft rot is sprayed for 1 time at intervals of 7 to 10 days and for 2 to 3 times continuously. When the disease is controlled, underground pests need to be controlled, so that the wound of the taro is reduced, and the infection of germs is relieved. The medicament can be poured by using 400 times of 18 percent bisultap solution. Taro diricht spot is controlled by spraying 500 times of 50% thiophanate methyl wettable powder and 600 times of 75% chlorothalonil wettable powder. It is administered once every 7-8 days for 2-3 times. 4.4 Spodoptera litura uses the following medicaments: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. 4.5 preventing and treating taro and single-thread hawkmoth in the middle and late 6 months by spraying 48% Lespede1500 times liquid, 800-1000 times liquid of BT powder and 1000 times liquid of 1.8% abamectin. 4.6 aphids can be prevented and treated by spraying 10 percent imidacloprid 4000-fold liquid and 10 percent high-power minister 4000-fold liquid from the first ten days of 5 months to the last ten days of 10 months. The spodoptera litura, wherein the spotter generation stage is performed before 3 instars of larvae, picking and controlling are performed by combining with a field pipe, and the larvae move out at night after 4 instars, and are sprayed before and after evening or sprayed together with the ground and the base of the taro plant during spraying. The used medicaments comprise: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. The taro caterpillar and the single-thread hawkmoth can be prevented and treated in the middle ten days of 6 months to the late ten days of 9 months by spraying 48 percent of Lesbane 1500-fold liquid, 800-1000-fold liquid of BT powder and 1000-fold liquid of 1.8 percent of abamectin. The aphid can be sprayed and prevented by 10 percent of imidacloprid 4000-times liquid and 10 percent of Chinese minister 4000-times liquid from the first ten days of 5 months to the last ten days of 10 months.

Step S10 picking and storing the purple yam: collecting and storing the mother taro.

Specifically, the taro leaves turn yellow and can be harvested, harvesting time can be arranged according to market conditions, and harvesting can be performed in the middle of 11 months to 2 months later. The ditch water must be drained 15-20 days before harvesting, so as to be beneficial to full conversion of nutrients and improve the quality. The harvesting should be carried out in sunny days, the whole plant is dug up, the water is dried in the air, the residual leaves and fibrous roots are removed, and the plant can be stored. And (4) harvesting healthy seed taros, storing the seeds in a classified mode, and planting the seeds in the next year. Or after the mother taro is harvested, the robust son taro is left in the field to overwinter, and the next year is harvested, sowed and cultured or self-growing seedlings are cultivated. The storing place of the yam is selected from a sandy field which is ventilated, exposed to the sun and good in drainage and is not planted with the betel nut yam in the current year. And digging a 30-40 cm-deep surrounding ditch around the storage land as a drainage ditch, and leveling the storage land for later use. After the mother taro is pulled up from the taro field, the stem of the taro is cut off, the mother taro is inverted and vertically arranged on the storage ground one by one, and the periphery and the upper part of the mother taro are covered with 10-20 cm layers of native people. The storage of the mother taro is finished in the same day after the mother taro is pulled from the taro field. The water content of soil in the storage land must be kept at 60-70%, the soil is sprayed with water for moisture preservation after being dried, and when the temperature is reduced to 5 ℃, the storage land is covered with sundries such as straws or covered with a plastic film for moisture preservation, and the snow water infiltration is strictly prevented.

Example 3

A planting method of selenium-rich purple yam is characterized by comprising the following steps: comprises the following steps

Step S1 planting site selection: it is suitable for paddy fields;

step S2 taro variety: selecting Arecae semen of Quercus of Araceae, HEZHOU rhizoma Steudnerae;

step S3 seedling raising of taro:

selecting seed taros which have strong terminal buds, no disease spot worm mouths and good corm shapes from disease-free mother plants as seed taros, selecting single seed taros of 50 g as seeds, and using the seed amount of each mu of seed taros as 100 kg; soaking the seeds of the taros in disinfectant for about 30 minutes, and airing and raising seedlings; selecting field blocks which are leeward and exposed to the sun, convenient to drain, fertile and loose in soil and 7.0 flat in pH value from the seedling culture land, and applying a seedbed fertilizer after sterilizing before sowing; adopting an inverted planting method to grow seedlings, and transplanting the seedlings to a field when the height of the seedlings is 15cm and 1 leaf is 1 heart;

specifically, the disinfectant is 1500 times of 50% phoxim missible oil 1000-; the method comprises the steps of disinfecting seedbed soil with quicklime in the seedling growing land, applying seedbed fertilizer after land preparation, applying about 550kg of decomposed farmyard manure to each mu of seedbed, and fully mixing the farmyard manure with the seedbed soil.

The method comprises the steps of placing the top end of each taro seed at the bottom of soil, inclining the tail end of each taro seed at an angle of 45 degrees, enabling the taro seed to be 10cm apart, then paving a layer of sandy soil to fill and fix the taro seed, covering a thin layer of plant ash on the taro seed to a thickness which does not expose the taro seed, covering a layer of straw on a seedbed, and covering a plastic film; the water content of the soil is kept at 70 percent, and the plastic film is turned over when the air temperature reaches above 15 ℃; the seedlings with thick and strong bud heads, snow white, regular germination, thick and short root systems, no disease spot and no leaf exposure can be used for planting.

Step S4 taro planting:

planting taro fields by using loam or sandy loam with deep, loose and fertile soil layers and a plough layer of more than 30cm, wherein the pH value of the soil is 7.0; the planting time is 3 late ten days to 4 middle ten days, when the temperature reaches above 15 ℃, planting is carried out on sunny days, and the root fixing water is drenched in time after planting. 2000 plants are planted in each mu, and the seedlings are planted in a single row or double rows, and the requirements on the quality, the thickness and the size of the purple yam seedlings during planting are basically uniform.

Step S5 taro fertilization: starting the first topdressing when the height of the seedling is 35-40cm, and applying for 2-3 times per month; starting secondary topdressing when the height of the taro seedlings is 50-55 cm; when the line is sealed in 6-7 months for the third time of topdressing, topdressing is carried out in combination with the taro earthing up and furrow application; topdressing is carried out for the last time before and after sunstroke, and seedling strengthening fertilizer is used for spraying roots once every 6-7 days for 3 times continuously, so as to achieve the purposes of inhibiting stem and leaf overgrowth and promoting corm expansion; specifically, the first topdressing is to apply 900 kg of 35% human excrement and urine fertilizer and 50kg of potassium nitrate per mu; the second topdressing is to apply 60 kilograms of ternary compound fertilizer per mu; 2000 kg of decomposed organic manure and 70 kg of ternary compound fertilizer are applied in the third topdressing; and the last topdressing is to apply 70 kg of imported compound fertilizer, 17 kg of biological potassium and 17 kg of biological phosphorus in each mu of hole. The content ratio of the ternary compound fertilizer is as follows: n: P2O 5: K2O ═ 15: 15: 15.

step S6 selenium fertilizer is applied to the purple yam: applying selenium fertilizer in the corm expansion period of the taros within 8-10 months, spraying 1500 times of selenium fertilizer liquid in a leaf surface spraying mode for 3 times, wherein the application amount is 100 ml/mu, and the interval of each time is 7-10 days; in this embodiment, the selenium fertilizer is a selenium carefree selenium fertilizer that is available on the market.

Step S7 weeding and ridging the taro: artificial weeding is carried out to prevent weeds from growing, and the weeding is to prevent the bulbs from being damaged and avoid using herbicides; cultivating and hilling the henry steudnera tuber for 3 times, wherein the 1 st time is in a leaf stage of 3-4, the 2 nd time is in a leaf stage of 6-7, and the 3 rd time is in a leaf stage of 9-10; the intertillage and hilling can be carried out by combining weeding and fertilization.

Step S8 taro water management: the soil of the taro at the early growth stage needs to be kept moist, and sufficient water needs to be supplied during the full growth period and the bulb forming period; the water management of the taro is specifically realized by keeping soil moist in the early and middle periods; after a sunstroke, a deep water layer of about 12-16cm is required to be kept in the ditch frequently, and the surface of the ridge is not flooded by water; after 8 ten days in the middle of the month, keeping the furrow water dry to increase the soil humidity, reduce the soil temperature and improve the field microclimate; after frost had passed, the bulbs had matured and water was drained 15 days before harvest.

Step S9 pest control of taro: adopting one or more of agricultural control, biological control, physical control and chemical control to carry out pest and disease control on the taro;

specifically, agricultural control: selecting disease-free seed taro or virus-free seed taro, soaking seed with insecticidal sterilizing liquid for sterilization, and transplanting seedlings with medicine. Biocontrol execution SN/T2118-2008 "guide for introduction of natural enemies and management of biocontrol", introduction of release of natural enemies and management of biocontrol. Biological pesticides such as matrine, abamectin, kasugamycin, agricultural streptomycin and the like, insect pheromones such as a prodenia litura sex attractant and the like, insecticidal plants such as tea seed cake, tobacco and the like, and mineral pesticides such as Bordeaux mixture and the like are selected to combine treatment by picking, common treatment and grass generation, so that natural enemies are protected and utilized. Physical control: the prodenia litura, scarab and the like are trapped and killed by a frequency vibration type insecticidal lamp. Manually killing mole crickets and removing egg masses such as prodenia litura and the like in a pest concentration area and an insect egg concentration area under a lamp. Chemical control: taro epidemic disease is prevented and treated by spraying 25 percent of wettable powder of Jiashuang Cu 600 times liquid, 64 percent of wettable powder of arsenopyrite 500 times liquid, 25 percent of clotrimazole 1000 times liquid, wettable powder of arsenopyrite 500 times liquid and 58 percent of wettable powder of Redox manganese-zinc 500 times liquid in the early stage of disease incidence, and the taro epidemic disease is sprayed for 1 time every 7 to 10 days and is sprayed for 3 to 4 times continuously. And (3) preventing soft rot of taro, namely preventing taro from soft rot in late 6 to 8 months, wherein the pesticide can be sprayed with 3000 times of 72% agricultural streptomycin wettable powder and 400 times of 25% cuaminosulfate aqueous solution, or sprayed with 1:1:100 Bordeaux solution or sprayed on roots for preventing taro soft rot, and the taro soft rot is sprayed for 1 time at intervals of 7 to 10 days and for 2 to 3 times continuously. When the disease is controlled, underground pests need to be controlled, so that the wound of the taro is reduced, and the infection of germs is relieved. The medicament can be poured by using 400 times of 18 percent bisultap solution. Taro diricht spot is controlled by spraying 500 times of 50% thiophanate methyl wettable powder and 600 times of 75% chlorothalonil wettable powder. It is administered once every 7-8 days for 2-3 times. 4.4 Spodoptera litura uses the following medicaments: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. 4.5 preventing and treating taro and single-thread hawkmoth in the middle and late 6 months by spraying 48% Lespede1500 times liquid, 800-1000 times liquid of BT powder and 1000 times liquid of 1.8% abamectin. 4.6 aphids can be prevented and treated by spraying 10 percent imidacloprid 4000-fold liquid and 10 percent high-power minister 4000-fold liquid from the first ten days of 5 months to the last ten days of 10 months. The spodoptera litura, wherein the spotter generation stage is performed before 3 instars of larvae, picking and controlling are performed by combining with a field pipe, and the larvae move out at night after 4 instars, and are sprayed before and after evening or sprayed together with the ground and the base of the taro plant during spraying. The used medicaments comprise: 2000 times of 20% lesie emulsifiable solution, 2000 times of 20% insecticide-killing emulsifiable solution, 2000 times of 40% fenvalerate emulsifiable solution, 1000 times of 50% cartap wettable powder, 3000 times of 5.7% Baishui emulsifiable solution and 2000 times of 2.5% Tianwangxing emulsifiable solution. One is selected at each time, the medicine is sprayed once every 5 to 10 days, the air temperature is high, the interval time is short, and the medicine is continuously sprayed for 2 to 3 times. The taro caterpillar and the single-thread hawkmoth can be prevented and treated in the middle ten days of 6 months to the late ten days of 9 months by spraying 48 percent of Lesbane 1500-fold liquid, 800-1000-fold liquid of BT powder and 1000-fold liquid of 1.8 percent of abamectin. The aphid can be sprayed and prevented by 10 percent of imidacloprid 4000-times liquid and 10 percent of Chinese minister 4000-times liquid from the first ten days of 5 months to the last ten days of 10 months.

Step S10 picking and storing the purple yam: collecting and storing the mother taro.

Specifically, the taro leaves turn yellow and can be harvested, harvesting time can be arranged according to market conditions, and harvesting can be performed in the middle of 11 months to 2 months later. The ditch water must be drained 15-20 days before harvesting, so as to be beneficial to full conversion of nutrients and improve the quality. The harvesting should be carried out in sunny days, the whole plant is dug up, the water is dried in the air, the residual leaves and fibrous roots are removed, and the plant can be stored. And (4) harvesting healthy seed taros, storing the seeds in a classified mode, and planting the seeds in the next year. Or after the mother taro is harvested, the robust son taro is left in the field to overwinter, and the next year is harvested, sowed and cultured or self-growing seedlings are cultivated. The storing place of the yam is selected from a sandy field which is ventilated, exposed to the sun and good in drainage and is not planted with the betel nut yam in the current year. And digging a 30-40 cm-deep surrounding ditch around the storage land as a drainage ditch, and leveling the storage land for later use. After the mother taro is pulled up from the taro field, the stem of the taro is cut off, the mother taro is inverted and vertically arranged on the storage ground one by one, and the periphery and the upper part of the mother taro are covered with 10-20 cm layers of native people. The storage of the mother taro is finished in the same day after the mother taro is pulled from the taro field. The water content of soil in the storage land must be kept at 60-70%, the soil is sprayed with water for moisture preservation after being dried, and when the temperature is reduced to 5 ℃, the storage land is covered with sundries such as straws or covered with a plastic film for moisture preservation, and the snow water infiltration is strictly prevented.

Through detection, the selenium content of the taro product obtained in the embodiment reaches more than 20 mug/kg. The method realizes the management from the seedling cultivation of the variety to the ripening of the purple yam by selecting the planting site of the purple yam, selecting the variety, cultivating the seedling of the purple yam, applying fertilizer, weeding, earthing up, managing water, preventing and controlling plant diseases and insect pests and the like by taking the excellent variety as the seed, and only adopting a spraying mode for many times in the process of enriching the selenium of the purple yam to enrich the selenium, wherein the selenium content of the harvested purple yam is more than 20 mug/kg; the method solves the technical problems of high production cost and complex operation caused by the fact that the selenium enrichment in the land needs to apply a large amount of selenium fertilizer in the land in the traditional method for absorbing the selenium element from the land by the selenium-enriched taro.

The above description is intended to describe in detail the preferred embodiments of the present invention, but the embodiments are not intended to limit the scope of the claims of the present invention, and all equivalent changes and modifications made within the technical spirit of the present invention should fall within the scope of the claims of the present invention.

Claims (8)

1. A planting method of selenium-rich purple yam is characterized by comprising the following steps: comprises the following steps

Step S1 planting site selection: it is suitable for paddy fields;

step S2 taro variety: selecting Arecae semen of Quercus of Araceae, HEZHOU rhizoma Steudnerae;

step S3 seedling raising of taro:

selecting seed taros which have strong terminal buds, no disease spot worm mouths and good corm shapes from disease-free mother plants as seed taros, selecting single seed taros of 40-50 g as seeds, and using the seed amount of 80-100 kg per mu; soaking the seeds of the taros in disinfectant for about 30 minutes, and airing and raising seedlings; selecting field blocks which are leeward and exposed to the sun, convenient to drain, fertile and loose in soil and flat in pH value of 5.5-7.0 in the seedling culture land, and applying a seedbed fertilizer after sterilizing before sowing; seedling is cultivated by adopting a reverse planting method, and the seedlings can be transplanted to a field when the height of the seedlings is 10-15 cm and 1 leaf and 1 heart are obtained;

step S4 taro planting:

planting taro fields by using loam or sandy loam with deep, loose and fertile soil layers and a plough layer of more than 30cm, wherein the pH value of the soil is 5.5-7.0; planting in 3 late ten days to 4 middle ten days, when the temperature reaches above 15 ℃, planting in sunny days, and pouring root fixing water in time after planting;

step S5 taro fertilization: starting the first topdressing when the height of the seedling is 35-40cm, and applying for 2-3 times per month; starting secondary topdressing when the height of the taro seedlings is 50-55 cm; when the line is sealed in 6-7 months for the third time of topdressing, topdressing is carried out in combination with the taro earthing up and furrow application; topdressing is carried out for the last time before and after sunstroke, and seedling strengthening fertilizer is used for spraying roots once every 6-7 days for 3 times continuously, so as to achieve the purposes of inhibiting stem and leaf overgrowth and promoting corm expansion;

step S6 selenium fertilizer is applied to the purple yam: applying selenium fertilizer in the expansion period of the corms of the taros for 8-10 months, spraying 1500 times of solution of the selenium fertilizer 1000 times in a leaf surface spraying manner for 3 times, wherein the application amount is 100 ml/mu, and the interval of each time is 7-10 days;

step S7 weeding and ridging the taro: artificial weeding is carried out to prevent the growth of weeds; cultivating and hilling the henry steudnera tuber for 3 times, wherein the 1 st time is in a leaf stage of 3-4, the 2 nd time is in a leaf stage of 6-7, and the 3 rd time is in a leaf stage of 9-10;

step S8 taro water management: the soil of the taro at the early growth stage needs to be kept moist, and sufficient water needs to be supplied during the full growth period and the bulb forming period;

step S9 pest control of taro: adopting one or more of agricultural control, biological control, physical control and chemical control to carry out pest and disease control on the taro;

step S10 picking and storing the purple yam: collecting and storing the mother taro.

2. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in step S3, the disinfectant is a 1000-fold liquid of carbendazim wettable powder, a 1000-fold liquid of 70% thiophanate methyl wettable powder, or a 1500-fold liquid of 1000-fold 50% phoxim emulsifiable concentrate.

3. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in step S3, the seedling field is disinfected by quicklime, the bed soil is fertilized after land preparation, about 450-550kg of decomposed farmyard manure is fertilized per mu of the bed soil, and the farmyard manure and the bed soil are fully mixed.

4. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in the step S3, the inverted planting method is to place the top end of the seed taro at the bottom of the soil, the tail end of the seed taro inclines towards 45 degrees, the distance between the taros is 5-10cm, then a layer of sandy soil is paved to fill and fix the seed taro, then a thin layer of plant ash is covered on the seed taro, the thickness is enough not to expose the seed taro, then a layer of straw is covered on the seedbed, and a plastic film is covered on the seedbed; keeping the water content of the soil at 50-70%, and turning over the plastic film when the air temperature reaches above 15 ℃; the seedlings with thick and strong bud heads, snow white, regular germination, thick and short root systems, no disease spot and no leaf exposure can be used for planting.

5. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in step S4, 1700-plus-2000 plants are field-planted per mu, and field-planted in single row or double rows, wherein the quality, the thickness and the size of the henry steudnera seedlings are basically uniform during field planting.

6. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in the step S5, the first topdressing is to apply 700 and 900 kilograms of human excrement and urine fertilizer with the concentration of 25-35% per mu and 25-50 kilograms of potassium nitrate; the second topdressing is to apply 50-60 kg of ternary compound fertilizer per mu; the third topdressing is 1500-2000 kg of decomposed organic manure and 60-70 kg of ternary compound fertilizer; the last topdressing is to apply 60-70 kg of imported compound fertilizer, 15-17 kg of biological potassium and 15-17 kg of biological phosphorus in each mu of hole.

7. The planting method of the selenium-rich purple yam according to claim 6, wherein the planting method comprises the following steps: the content ratio of the ternary compound fertilizer is as follows: n: p₂O₅：K₂O＝15：15：15。

8. The planting method of the selenium-rich purple yam according to claim 1, wherein the planting method comprises the following steps: in the step S8, the water management of the taro is specifically to keep the soil moist in the early and middle period; after a sunstroke, a deep water layer of about 12-16cm is required to be kept in the ditch frequently, and the surface of the ridge is not flooded by water; after 8 ten days in the middle of the month, keeping the furrow water dry to increase the soil humidity, reduce the soil temperature and improve the field microclimate; after frost had passed, the bulbs had matured and water was drained 15 days before harvest.