What is the harm of root-knot nematodes? What kind of pesticide can be killed?

What is the harm of root-knot nematodes? What kind of pesticide can be killed? Ask experienced netizens to help introduce a wide range of root-knot nematodes, which are often harmful to melons, eggplant fruits, legumes, radishes, carrots, lettuce, cabbage and more than 30 kinds of vegetables, so the farming network has sorted out the harm and control methods of root-knot nematodes, which are listed in detail below for netizens' reference. The harm of root-knot nematodes: root-knot nematodes mainly damage the roots of all kinds of vegetables. after the roots are damaged, the plants are stunted, the whisker roots and lateral roots increase, and nodules of different sizes are formed in the roots, which are white at first and soft in texture. and then turn brown to dumb brown. The aboveground growth of the injured plant was short, slow, abnormal leaf color, less fruit, low yield, and even caused the whole plant to wither and die. Control methods of root-knot nematodes: first, use contact nematode insecticide phenylphosphos: 10% granule 3000g / mu is used in the soil along with the crop sowing, or in the soil near the rhizosphere during the crop growing period. Method 2. Use nematicidal nematodes to kill nematodes: 20% granule 3.5 kg per mu is applied or sprayed in the soil (note that nematodes can not be in direct contact with crop seeds, which is prone to drug damage). Method 3. Use fumigation nematicidal agent Weibai mu: 3 kg of 35% aqueous solution per mu, 300 kg of water, ditch the potion half a month before sowing, cover the soil, and sow after 15 days. Method 4. Use fumigation nematode insecticide Mianlong: apply with 11kg per mu or ditch, and cover the soil immediately after application, which can effectively kill nematodes. What is methylaminoavermectin benzoate? What is a red spider?