1 Cowpea basal rot
2 Root rot
3 Hornblotch
4 Gray mold
5 Brown-margined white-star disease
6 Red blotch
7 Botrytis
8 Epidemic
9 Spotted blight
10 Coal rot
11 Blight
12 Rust
13 Powdery mildew
14 Anthracnose
15 Verticillium verticillioides
16 Black streak gerbil black spot
17 Cowpea streak gerbil black spot (a disease that is not the same as 16 and 17)
18 Stem blight
119 White serotinous disease
20 Bacterial blight
21 Phytophthora
22 Black-eyed cowpea mosaic virus disease
23 Phytophthora clusters
24 Root-knot nematodes
Listing some of the major ones, to be more specific:
(I) Major diseases and their control
1. Cowpea virus disease: It is a relatively common and serious disease. The common ones are cowpea leaf disease and cowpea yellow leaf disease. The main virus pathogens are cowpea aphid-borne mosaic virus and cucumber mosaic virus. The disease is characterized by yellow spots on the leaves, yellow-green and dark green spots, deformities, severe plant dwarfism, and even failure to flower or even death. Prevention and control: establish disease-free seed fields, select disease-resistant varieties, select seeds, cultivate strong seedlings, improve the plant's own disease resistance; crop rotation, avoid heavy cropping, strengthen fertilizer management, increase the application of phosphorus and potassium fertilizers; diseased plants, diseased leaves and timely removal of the burnt, reduce the source of disease. Before or at the beginning of the onset of the disease, the use of 200 times the Bordeaux solution or 50% carbendazim wettable powder 500-800 times, or 50% tolbutamide wettable powder 600-1000 times and other fungicides to prevent fungal diseases. Aphids are found in time to spray 40% of the Lego emulsion 1000 times or 80% of the dichlorvos emulsion 1000-1500 times to prevent and control aphids, focusing on spraying the back of the leaf. Eliminate the source of virus. After the occurrence of virus disease, give more fertilizer, and spray 0.1%-0.5% potassium dihydrogen phosphate, can reduce the loss.
2, cowpea coal mold: also known as leaf mold or leaf spot disease, is a more serious leaf disease in recent years. Initially, the leaf blade occurs red, purple brown dots, expanding nearly round spots, when wet, the back of the leaf produces gray-black mold, resulting in smaller leaves, defoliation, pod reduction. Prevention and control: strengthen field management, reasonable dense planting, make the field ventilation and light, prevent excessive humidity, increase the application of phosphorus and potassium fertilizer, improve plant resistance, remove the diseased leaves in the early stage of the disease, clean the field after harvest, reduce the spread of the disease. Pharmaceutical control: available 1:1:200 Bordeaux solution, 25% carbendazim wettable powder 400 times, or 50% tolbutamide wettable powder 500 times, or 75% chlorothalonil wettable powder 600 times, or 65% zinc diclofenac wettable powder 500 times, 1 time every 10 days, 2-3 consecutive control.
3, cowpea rust: mainly for leaf, heavy petiole and seed pods can also be harmful. At the beginning, the back of the leaf produces small yellowish spots that gradually turn brown, bulge into a small pustule, then expand into a pile of summer spores, and when the epidermis ruptures, a reddish-brown powder is dispersed that is summer spores, and then a pile of black winter spores is formed, which results in the deformation of the leaves and the early fall of the leaves. Preventing and controlling: Choose disease-resistant varieties, spray 15% triazolone wettable powder 1000-1500 times or 50% chlormequat chloride emulsion 800 times, etc., 1 time in 10-15 days, and spray 2-3 times in a row.
4, cowpea powdery mildew: the main damage to the leaves, but also for the vines and pods. Beginning in the back of the leaf yellow-brown spots, then expand into purple-brown spots, covered with a thin layer of white powder, leaf spots along the veins development, white powder covered with the whole leaf, causing a lot of leaf drop. This disease is common in the south. Prevention and control: choose disease-resistant varieties, remove the diseased plants in time after harvest, centralized burned or buried; spray 70% thiophanate-methyl wettable powder 500 times liquid or 30% solid sulfuric acid 150 times liquid, 50% sulfur suspension 300 times, 7-10 days, spray 1 time, 3-4 times in a row.
5, cowpea wilt: the main disease in the seedling stage. The symptom is to cause root rot and plant wilt. It is mainly controlled by crop rotation, pulling out diseased plants and strengthening field management.
(2) Main pests and control
1, small tigress: also known as the "groundworm", is the main pest for seedlings. Its larvae in the topsoil layer or the surface of the damage, before the 3rd instar larvae nibble seedling leaves into the mesh, 4 instars after biting off the young stems of seedlings, resulting in seedling breaks and a large number of seedling deaths. Prevention and control: early spring eradication of weeds, reduce the small tigress spawning sites and sources of food, poison bait to kill the larvae below the age of 4, will be 5 kg of wheat bran fried mixed into trichlorfon hot solution 10 times liquid. Small tigress feeding early, with 25% dichlorvos or 25% speed kill Ding 2500 times liquid spray plant base and around, the effect is better, can also be combined with artificial catch and kill larvae.
2, bean wild stem borer (pod borer): also known as pod wild stem borer or cowpea heartworm. Bean wild (pod) borer larvae mainly damage the leaves before buds, and later on, they drill into the corolla and young pods to feed on and damage, causing the shedding of buds and pods, and producing moth holes after feeding, and producing feces to cause pods to rot, which seriously affects cowpea's yield and quality. Preventing and controlling: to be timely, find larvae in cowpea blossoming period immediately with 10% cypermethrin emulsion or 50% fenitrothion emulsion or 25% trichlorfon powder or 80% dichlorvos emulsion 1,000 times spraying to kill, 1 time in 7-10 days interval, continuously spraying 2-3 times. Selection of early maturing varieties, the implementation of intercropping with food crops, to maintain a certain degree of humidity in the field can reduce the damage.
3, aphids: cowpea is the main insect pest, and cowpea virus disease is one of the main vector, in the seedling period to the whole growth and development period can be harmful. Preventing and controlling: at the early stage of aphids, use 40% Rogaine emulsion or 40% oxidized Rogaine emulsion 1000-1200 times, Antiaphid 800 times, 50% Dichlorvos 1000 times or Dichlorvos 2000-3000 times, focus on spraying the back of the leaves, spray every 7-10 days, spray 2-3 times in a row.
4, red spider: also known as fire dragon. Adults and larvae gather at the back of the leaves to suck sap, and after the leaves are damaged, they gradually turn reddish-yellow, like fire, and finally the leaves fall off, and the fruits dry up, and the plants turn yellow and scorch. Prevention and control: available 20% dicofol emulsion 1000 times liquid, 90% trichlorfon 800-1000 times or 40% oxolinic acid emulsion 1000-1500 times or trisulfoton and other agents alternately sprayed, focusing on spraying the back of the leaf, sprayed 2-3 times in a row.
5, bean weevil: also the most serious pest on cowpea. Adults lay eggs on young pods, and after the eggs hatch, the larvae feed on the seeds to infest them, so that the seeds become empty shells and are inedible, seriously affecting the germination of seeds and their commercial quality. Prevention and control: Insecticides can be sprayed during the flowering period, and after harvesting the seeds and drying them in the sun, pharmaceutical fumigation can be used. Generally aluminum phosphide or chlorinated bitter fumigation of beans and storage tanks, can kill both insects and eggs. Some places also use boiling water immersion, lime tank or sealed storage methods, can also achieve certain control effects.