Symptoms and control of kidney bean powdery mildew

Kidney beans are suitable for planting in temperate and tropical high-altitude areas. Kidney beans are more resistant to cold and light than cross-pollinated beans and short-day crops. Kidney beans have well-developed roots, green leaves, alternate leaves, heart-shaped flowers, racemes and pedicels 15-18 cm long.

Growth environment of kidney bean

Kidney beans like warmth and are not resistant to frost. The optimum temperature for seed germination was 20-25 ℃, and germination was blocked below 8 ℃ or above 35 ℃. The optimum temperature for seedling growth was 18-20 ℃, and chilling injury occurred at 8 ℃. The suitable temperature for flowering and pod setting is 20-25 ℃, and incomplete flowers are easy to appear when the temperature is higher than 27 ℃ or below 15 ℃, which leads to flower and pod drop.

Kidney bean is a short-day vegetable, but most varieties are not strict about the length of sunshine and can be cultivated in four seasons, so it is known as "kidney bean". All parts of the north and south can be introduced to each other.

Kidney beans do not have strict requirements for soil quality, but they are suitable for growing in neutral loam with deep soil layer, good drainage and rich organic matter. Kidney beans require more phosphorus and potassium, and nitrogen is also needed. In the seedling stage and bud stage, there must be an appropriate amount of nitrogen fertilizer supply in order to ensure high yield.

Kidney beans are required to be moist throughout the growth period. Because the root system is well developed, it can withstand a certain degree of drought, but it is especially sensitive to lack of water or stagnant water when blooming and bearing pods. Too much water will cause rotten roots.

Adzuki bean is a temperature-loving plant. The suitable temperature for growth is 15: 25 ℃, and the suitable temperature for flowering and pod setting is 20: 25 ℃. Low temperature below 10 ℃ or high temperature above 30 ℃ will affect growth and normal pollination and pod setting. It belongs to short sunshine plant, but most varieties do not have strict requirements for sunshine length, and the cultivation season is mainly restricted by temperature.

Symptoms and control of kidney bean powdery mildew

Symptoms of kidney bean powdery mildew:

Mainly damage leaves, stems and pods can also be damaged. Cause premature senescence of the plant. Stem pod disease appears small powder spots, serious covered with stem pods, resulting in stem pods withered yellow or even dry shrinkage.

Prevention and control of kidney bean powdery mildew:

① disinfection of seeds: seeds can be treated with 70% methyl topiramate wettable powder or 50% carbendazim plus 75% carbendazim wettable powder (1:1) (0.3% 0.4% of seed weight) and sealed for 48-72 hours before sowing, the disease can be delayed for about 1 month.

② should strengthen management and cultivation, carry out rotation if possible, avoid planting in low wetlands, reasonably close planting, reasonable border arrangement, rectify orderly drainage and irrigation system, clear ditches and drainage after rain, especially increase phosphorus and potassium fertilizer, avoid excessive application of nitrogen fertilizer, and pay attention to field hygiene.

③ timely spraying to prevent and control disease, timely disease prevention, we should adhere to the principle of "early treatment, less prevention, cure". And pay attention to mixing and rotation, spray evenly, spray foot.