Control of soft rot of zucchini

Zucchini soft rot mainly harms the roots and fruits of zucchini. In the melon-bearing period, the stem vine and petiole base first showed a water stain, especially in the natural crack or wound, the rhizome gradually softened, the diseased part was sunken, the internal tissue rotted, forming a grayish brown sticky substance, with a foul smell, water evaporation in the affected part, and tissue shrinkage. The pathogen overwinters in the soil. The soft rot of zucchini in general protected areas is mainly caused by the soft rot of cabbage. The pathogen can only be invaded by the wound through Rain Water, irrigation water and insects. After the invasion, the bacteria secrete Pectinase to dissolve the glue layer, resulting in cell disintegration and intracellular water spillover. Cause rot. High temperature, high humidity, dry pruning and branching of zucchini in rainy days or dew, injury of leaves and insect pests in farmland operation, which often cause bacterial infection and lead to the occurrence of soft rot of zucchini. The prevention and control methods are as follows: disease-resistant varieties should be selected in different areas according to the disease characteristics of zucchini in local protected areas. Agricultural measures to prevent and control 1, avoid continuous stubble with cabbage vegetables, the first stubble choice is onion, garlic or eggplant fruit vegetables. 2. Quicklime or potassium permanganate must be used for soil disinfection before soil preparation. The dosage of quicklime 667 square meters is 50-100 kg, and that of potassium permanganate is 2-2.5 kg. 3. Grafting and raising seedlings. Using black-seeded pumpkin as rootstock for grafting cultivation, the root system of the plant was strong, the low temperature tolerance was improved and the disease resistance was enhanced. 4. High ridge was used to cover plastic film cultivation. 5. rational application of nitrogen fertilizer and increase of phosphorus and potassium fertilizer. 6. Pay attention to irrigation, adopt drip irrigation under plastic film under conditions, avoid flood irrigation, timely drainage after rain, avoid stagnant water in the field; 7. Strengthen the prevention and control of other diseases and insect pests, and mainly do a good job in the prevention and control of whitefly and aphids during the whole growth period. 8. The agricultural operation should be careful to avoid mechanical damage, and the row spacing can be appropriately increased and the plant spacing can be reduced, which is beneficial to the field operation. 9. Remove and bury the diseased melon in time, and disinfect the disinfected melon with quicklime. Chemical control zucchini colonization, pruning before the use of chemical prevention; in the initial stage of the onset of soft rot, 72% agricultural streptomycin and other spraying, alternately sprayed every 7 days, continuous prevention and control 2 Mel 3 times.