CN111201976A - Covering plant combination for preventing and controlling soft rot of konjak and application - Google Patents

Abstract

The invention discloses a covering plant combination for preventing and controlling soft rot of konjak and application thereof. The cover plant combination of the invention covers 6 families of herbaceous plants, the plant shape and function collocation are scientific, the plant growth is rapid, vegetation with proper density and height can be formed on the konjak planting ridges, and the growth of field weeds is inhibited; the soil surface is kept cool and the soil holds water, so that the diversity of soil microorganisms is increased, the beneficial soil microbial community is promoted, and the growth and proliferation of harmful soft rot germs are inhibited; meanwhile, vegetation formed by covering the plant combination inhibits and kills field pests, reduces insect damage wounds of tubers and leaves of the konjak plants, and reduces the probability of infecting the konjak by soft rot pathogenic bacteria. The covering plant combination is applied to ecological prevention and control of the soft rot of the konjak, chemical pesticide soil disinfection is not needed for konjak planting any more, green, efficient and sustainable development of konjak planting industry is supported, and quality safety of konjak products is guaranteed.

Description

Covering plant combination for preventing and controlling soft rot of konjak and application

Technical Field

The invention belongs to the technical field of ecological regulation and control of diseases of cash crops, and relates to a covering plant combination for preventing and controlling soft rot of konjak and application thereof.

Background

The tuber of the konjak is food material and medicinal material, has the efficacies of reducing blood pressure, losing weight, promoting urination, dispelling toxin, beautifying, stimulating appetite, preventing cancer and the like, is determined as one of ten health-care foods by the health organization of the United nations, is widely applied to the industries of food, medical treatment, chemical industry, paper making, textile, petroleum and the like due to the richness of high-quality starch, protein, amino acid, glucomannan, trace elements and the like, and is called as 'oriental magic powder'. Konjak is mainly distributed in Asia, African tropical and subtropical countries and regions, China is the origin and the first country of production, the planting area is over 150 ten thousand mu throughout the year, and the yield accounts for about 60 percent of the world. The konjak industry becomes the characteristic industry with competitive advantages and development potential in agriculture in Qinba, Yungui mountain areas and rural economic development in China. The soft rot is the most serious disease in konjak production, is a bacterial disease and is caused by carrot soft rot pectobacterium and chrysanthemum pectobacterium, germs mainly live through the winter in soil or corms along with disease residues and become a main initial infection source, the number of the germs can be increased through the enrichment effect of a root system to finally reach the amount required by pathogenesis, the germs invade from tender tissues and wounds, the disease occurs in the whole growth period, the occurrence rate of the disease of a continuous cropping field is 35-50% higher than that of a non-continuous cropping field on average, the yield is reduced by 50-80%, and the disease is even completely harvested. At present, the konjac has the defects of lack of disease-resistant varieties, poor chemical pesticide control effect, high cost, poor konjac growth potential, serious disease, low yield and unsatisfactory benefit.

The konjak is a semi-negative plant, is not resistant to high temperature and drought, and is beneficial to the growth of the konjak by cooling and moisturizing the ground surface. At present, konjak is successfully planted in a shading mode, and mainly planted under forests (such as loquats, kiwis and the like) or intercropped with long-stalked crops (such as corns, castor beans and the like). Konjak is generally planted in ridges, malignant weeds on the ridges are unfavorable for the growth of konjak, chemical herbicides are inevitably used, and side effects are obvious. The covering plants are other plants than target crops and artificially planted, have the function of controlling weeds or covering bare ground, and can inhibit the growth of the weeds, reduce the impact of rain on soil, keep the soil in a certain loose state and be beneficial to the growth of the root system of the konjak and the expansion of corms by adopting the proper covering plants. In the practice of konjak planting production, a few farmers broadcast single pasture on konjak planting ridges for the purpose of cooling and moisturizing the ground surface, wherein the pasture is mainly red and white clover of leguminosae. Theoretically, the prevalence processes of the pathogenic bacteria of the soft rot of the konjak and other soil-borne pathogenic bacteria of crops are different, the antagonistic microorganism compositions and communities of the pathogenic bacteria are also different, the plants are covered by targeted screening, and the reasonable plant combination is beneficial to increasing the diversity of microorganisms, improving the microbial community structure, regulating and controlling the populations and communities of beneficial/harmful microorganisms by changing the physicochemical and nutrient contents of soil, so that the aim of reducing the occurrence of the disease of the konjak is finally achieved.

Disclosure of Invention

The invention aims to provide a covering plant combination for effectively inhibiting konjac soft rot, and fills the gap of research and development of the covering plant combination in ecological prevention and control of the konjac soft rot.

The invention also aims to provide the application of the covering plant combination in ecological prevention and control of the soft rot of the konjak, and the problem of serious soil-borne diseases in konjak production is solved.

The above purpose of the invention is realized by the following technical scheme:

a covering plant composition for effectively inhibiting konjac soft rot comprises, by mass, 40-60% of gramineous herbs, 20-30% of leguminous herbs, 3-9% of compositae herbs, 5-10% of umbelliferae herbs, 5-10% of Polygonaceae herbs and 2-8% of purslane herbs.

Preferably, the gramineous plant is cogongrass, and the seed mass accounts for 50%.

Preferably, the leguminous plant is alfalfa, and the mass ratio of the seeds is 25%.

Preferably, the feverfew species is chrysanthemum nankingense, and the mass percentage of the seeds is 6%.

Preferably, the plant of the Umbelliferae family is fructus cnidii, and the mass percentage of the seeds is 7%.

Preferably, the Polygonaceae plant species is buckwheat, and the seed mass ratio is 7%.

Preferably, the purslane plant is purslane, and the weight percentage of the seeds is 5%.

The application of the covering plant combination in ecological prevention and control of the soft rot disease of the konjak comprises the following steps:

1) preparing a ground;

2) sowing, namely sowing the combined grass seeds of the covering plants on the konjak planting ridges;

3) and (4) field management, namely ensuring the emergence and growth of the covering plants according to normal fertilizer and water management of the konjak field.

Preferably, when preparing the field in the step 1), the konjak is planted in two rows by ridging, the ridge height is 30cm, the ridge width is 80cm, and the ridge surface is smooth and loose.

Preferably, in the step 2), after the seedlings of the konjac are aligned, the covering plant combined grass seeds are uniformly mixed with sand and then are sowed on the surface of the konjac planting ridge by hand, the weight of the sowed grass seeds per square meter is 5g, and the sowing soil is 1 cm.

Preferably, in the step 3), during field management, the soil on the ridge surface is guaranteed to be moist within 2-3 weeks after sowing, and the covering plants are promoted to emerge in order and cover the ridge surface quickly. .

The invention has the following advantages and beneficial effects:

the cover plant combination of the invention covers 6 families of herbaceous plants, the plant shape and function collocation are scientific, the plant growth is rapid, vegetation with proper density and height can be formed on the konjak planting ridges, and the growth of field weeds is inhibited; the soil surface is kept cool and the soil holds water, so that the diversity of soil microorganisms is increased, the beneficial soil microbial community is promoted, and the growth and proliferation of harmful soft rot germs are inhibited; meanwhile, vegetation formed by covering the plant combination can inhibit and kill field pests by utilizing natural enemies, reduce insect damage wounds of stems and leaves of konjak plants and reduce the probability of infecting konjak by soft rot pathogenic bacteria. The covering plant combination is applied to ecological prevention and control of the soft rot of the konjak, chemical pesticide soil disinfection is not needed for konjak planting any more, green, efficient and sustainable development of konjak planting industry is supported, and quality safety of konjak products is guaranteed.

Detailed Description

For better understanding of the essence of the invention, the technical contents of the invention are described in detail below with reference to examples, but the contents of the invention are not limited thereto and thus should not be construed as limiting the scope of the invention.

Example 1: preferred combinations of cover plants

Preferred combinations of cover plants comprise, in mass percent: 50% of Graminaceae Cymbopogon citratus, 25% of Leguminosae alfalfa, 6% of Compositae chrysanthemum nane, 7% of Umbelliferae fructus Cnidii, 7% of Polygonaceae buckwheat, and 5% of Portulaca oleracea.

Example 2: influence of combination of covering plants on generation of soft rot of konjak and yield of konjak

In a Shanxi Ankang konjak large-area planting area, konjak is traditionally planted in an intercropping mode of konjak and corn, konjak is planted on ridges in double rows, the ridge height is 30-40cm, the ridge width is 60-100cm, and corn is planted in furrows in a single row. The fertilizer and water management in the test area is carried out according to the local conventional operation, and 500kg of farmyard manure and 25kg of phosphate fertilizer are applied per mu as base fertilizers. Treatments and controls were set, the treatments being konjac planted with the preferred combination of cover plants and the controls being traditional chemically herbicidal konjac. 3 repeated plots, 0.5 acre each, were set for treatment and control. From the initial stage of the konjac to the final stage of the expansion period, the surface temperature of the soil is monitored at 2 pm every day, and the temperature range of the whole period is counted. In the expanding period (about 8 months and 10 days and the high-incidence period of the soft rot of the konjak), 50 konjak plants are investigated, the number of plants damaged by the soft rot is recorded, typical soft rot symptoms comprise rotten leaves, petioles and tubers and have foul smell, and the incidence rate of the soft rot disease is calculated; meanwhile, collecting a soil sample, extracting DNA of the soil sample, carrying out high-throughput sequencing analysis on the diversity of soil microorganisms, and calculating the Shannon index. And continuously observing the seedling falling condition of the konjak plants from the expanding period of the konjak, and calculating the number of days required for 50 percent of the seedlings to fall. And (3) in the konjak harvesting period (about 10 months), taking out all konjak bulbs, weighing and counting, and measuring the acre yield.

TABLE 1 occurrence of soft rot of konjak and konjak yield

Test object	Surface temperature range (. degree. C.)	Microbial diversity shannon index	Disease incidence (%)	50% of the time of plant seedling falling (Tian)	Yield (kg/mu)
						Treatment (plant cover plant combination)	23.6~28.5	3.02	12	75	2720
Control (combination of cover plants not planted)	25.0~30.3	2.55	42	60	1460

Note: the data in the table are the average of 3 replicates.

The plant covered by the plant combination of the invention grows quickly, and can quickly form vegetation with proper density and height on the konjak planting ridges. As shown in Table 1, the treated combination of the cover plants reduces the surface temperature of the konjac at 2 pm every day in the onset period of the soft rot of the konjac, and avoids the disadvantage of high temperature on the growth of the root system of the konjac. In the expanding period of the konjak, the diversity of soil microorganisms is improved by covering the plants for combined planting, particularly the capability of inhibiting bacterial diseases is possibly enhanced, the disease incidence rate of konjak plants in a treated area is far lower than that of a control, and is reduced by 71.4 percent. Half of the konjak plants treated by the method need to be transplanted for 75 days, the time is prolonged by 15 days compared with that of the control, and the late transplantation is beneficial to the continuous growth and development of the konjak plants. Finally, the yield per mu of the treated product reaches 2720, which is 86.3% higher than that of the control. Therefore, the preferable cover plant combination has good effect when being applied to ecological prevention and control of the soft rot of the konjak, and chemical pesticide disinfection of soil before konjak planting is avoided.

Claims (2)

1. The covering plant composition for preventing and controlling the soft rot of the konjak and the application are characterized in that the flower and plant composition comprises the following components in percentage by mass: 40-60% of gramineous herbs, 20-30% of leguminous herbs, 3-9% of compositae herbs, 5-10% of umbelliferae herbs, 5-10% of polygonaceae herbs and 2-8% of purslane family herbs;

preferably, the gramineous plant is cogongrass, and the mass percentage of seeds is 50%;

preferably, the leguminous plant is alfalfa, and the mass ratio of seeds is 25%;

preferably, the feverfew species is chrysanthemum nankingense, and the mass percentage of the seeds is 6%;

preferably, the Umbelliferae plant is cnidium fruit, and the mass percentage of seeds is 7%;

preferably, the Polygonaceae plant species is buckwheat, and the mass percentage of the seeds is 7%;

preferably, the purslane plant is purslane, and the weight percentage of the seeds is 5%.

2. Use of a cover plant combination according to claim 1, wherein the preferred cover plant combination is suitable for ecological control of soft rot of konjac.