Harmful symptoms and Control methods of Peanut Stem Rot

Peanut stem rot, commonly known as rotten neck disease, is distributed in all peanut producing areas across the country. It generally occurs in the middle and later stages of the disease. Soon after it is infected, it withered and died. Pods often rot or seeds are dissatisfied, resulting in serious losses. The general field incidence rate is 2030%. In serious cases, it reaches 60% to 70%, especially peanut plots that have been cropped for many years and even die in patches. Let's take a look at the prevention and control methods of peanut stem rot.

Symptoms of peanut stem rot

The pathogen invades the plant from the cotyledons or young roots, producing yellowish-brown watery spots in the root neck, and then turning dark brown, causing the root tissue to rot. When in a humid environment, the diseased part produces conidia (that is, small black protuberances), the epidermis of the diseased part is easy to peel off and the fibrous tissue is exposed. When the environment is dry, the epidermis of the diseased part is sunken, close to the stem, and after the adult plant is infected, the whole plant dies in about 10-30 days, and the disease site is mostly close to the ground at the base of the stem, and sometimes the main stem and side branches die by stages.

Incidence conditions of peanut stem rot

The pathogen overwintered mainly on diseased and residual plants in seeds and soil and became the source of disease in the second year. If the diseased plant as a beverage or pod shell after raising livestock manure, as well as mixed with diseased plants accumulated soil manure can also spread. The transmission in the field mainly depends on Rain Water runoff, followed by strong wind, but germs can also be transmitted in the process of agricultural operation. In rainy and wet years, especially in the harvest season, the bacteria-carrying rate of harvested seeds is higher, so it is not only the main disseminator of the disease, but also can spread over a long distance through introduction.

Agricultural Control of Peanut Stem Rot

1. Select superior varieties: Yuhua 7, Yuhua 8, Yuhua 9, Luhua 11 and so on are better varieties.

2. Manage the seeds: peanuts used as seeds should be harvested in time, dried in time, stored in a ventilated and dry place, moistureproof and mildew-proof, and should be carefully selected and dried before sowing to facilitate germination and emergence.

Chemical Control of Peanut Stem Rot

1. Medicament soaking seeds: use 50% carbendazim wettable powder and new high fat film to press 5% of the seed amount, add fine soil 1.5 × 2 kg to spray water, then mix well, accelerate germination and sow, which can ward off underground diseases and insects, isolate virus infection, do not affect germination and swelling function, strengthen the absorption intensity, and improve the seed germination rate.

2. Medicament spray: use 50% carbendazim wettable powder 600x liquid or 70% carbendazim plus 50% carbendazim powder spray during the growing period, spray once after peanut seedlings and before and after flowering, or spray 1 or 2 times at the initial stage of the disease. Purek 800-1000 times liquid spray can also treat peanut root rot, root blight, leaf spot and so on.

How to control cowpea base rot? Control methods of cowpea base rot

Cowpea base rot, also known as standing blight, mainly threatens crops such as cowpea, bean, cotton, peanut, sweet potato and so on. So how to control cowpea base rot? What are the prevention and control methods of cowpea base rot?

How to control cowpea base rot? Control methods of cowpea base rot

1 before sowing or transplanting, or after harvest, remove weeds in the field and around, concentrate on burning or retting fertilizer; turn the ground deeply to kill stubble, promote the decomposition of disease residues and reduce pathogens and parasites.

(2) the seedlings were raised in the plot with good drainage and high dryness, the new soil without bacteria was selected in the seedling bed, and the bed soil was fully dried before raising seedlings.

The nursery bed should be selected in a place with leeward, sunny, high dryness and convenient drainage and irrigation, and disease-free soil should be selected as nutritional soil; the organic fertilizer in nutritious soil should be fully mature; and the nutritious soil should be exposed to the sun for at least three weeks before use.

3 and non-undergraduate crop rotation, flood-drought rotation is the best.

(4) choose disease-resistant varieties, disease-free and coated seeds. If uncoated, the seeds should be sterilized with seed dressing agent or seed soaking agent.

(5) selecting the fields with convenient drainage and irrigation, opening the drainage ditch, lowering the groundwater level, so that there is no stagnant water in the rain; cleaning up the ditch system in time after heavy rain to prevent moisture retention and reduce the humidity in the field is an important measure to prevent disease.

(6) early sowing at the right time, early transplanting, early seedling, early soil cultivation, early fertilization, timely ploughing and soil cultivation to cultivate strong seedlings.

7Seedling and transplanting, sprinkling a thin layer of medicinal soil at the bottom of the seedling bed, covering it with medicinal soil after sowing, and spraying insecticide and fungicide before transplanting, which is the key to disease prevention.

8 fields with many soil germs or serious underground pests, soil that is sterilized or killed in ditches before sowing

9 compost made by enzyme bacteria retting or mature organic fertilizer shall not be used without bacteria-carrying fertilizer, and the organic fertilizer shall not contain plant disease residues.

10 adopting the technology of soil testing and formula fertilization, properly increasing the application of phosphorus and potassium fertilizer, strengthening field management, cultivating strong seedlings, and enhancing plant disease resistance are conducive to reducing diseases.

11 plastic film mulching cultivation can prevent germs from harming aboveground plants in the soil.

12 avoid pruning in cloudy and rainy weather; timely control pests, reduce plant wounds, reduce pathogens transmission; timely prevention and control, and remove diseased leaves and diseased plants, take them out of the field for burning, disease point application or quicklime.

13 those cultivated in the greenhouse can be irrigated in the greenhouse during the summer leisure period, covered with plastic film on the ground, closed for several days, and sterilized by high temperature.

14 Scientific irrigation should be applied during high temperature and drought to increase field humidity, reduce the harm of aphids and gray planthopper and spread virus. Continuous irrigation and flood irrigation are strictly prohibited. Preventing water droplets from splashing during watering is an important measure to prevent the disease.

Control methods of maize bacterial wilt

Maize bacterial wilt, also known as maize stem rot, is an important soil-borne fungal disease that damages the root and stem base of corn. The incidence rate in our province is generally 10%, 20%, and more than 30% seriously. Once bacterial wilt occurs, the whole plant dies quickly, generally only 5-8 days, fast only 2-3 days.

First, select disease-resistant varieties

Planting disease-resistant varieties is one of the most economical and effective control measures. The improved maize varieties such as Ludan 50, Ludan 981, Nongda 3138 and Yuyu 22 cultivated in recent years have both high yield and disease resistance, so they can be popularized and planted in production.

Second, crop rotation to change stubble

Planting corn in the same plot year after year can cause a large number of pathogens to accumulate in the soil, and the disease will be aggravated year by year. If rotation is carried out with non-host crops such as soybean and peanut, the occurrence of disease can be significantly reduced.

Third, use coated seeds

Seed coating agent contains bactericidal components and trace elements, which can not only resist pathogen infection, but also promote seedling growth and enhance disease resistance. The dosage of seed coating agent is 1: 40-1: 50 of the seed amount. Using zinc and potassium fertilizer, the pathogen of corn bacterial wilt is a weak parasite, which occurs in large numbers only when the growth of corn is weak in the middle and later stage. The application of zinc and potassium fertilizer can make maize grow healthily, greatly improve the disease resistance of maize and reduce the incidence of disease. The method is as follows: 1.5-2kg zinc fertilizer and 10-15kg potash fertilizer are used for every 15 ha of corn seedling, and the hole is applied to the base of corn stem 7-10cm after mixing. When sporadic diseased plants are found in the middle and later stages of corn growth, 400 times of metalaxyl or 500 times of carbendazim can be used to irrigate roots with 500ml per plant, which has a better therapeutic effect.