Viral diseases mainly depend on prevention. First of all, we should pay attention to the management of vector pests such as whitefly and aphid. Strengthening fertilizer and water management is conducive to resisting viruses. If a small number of infected strains are found, they should be removed in time to avoid infection. The recommended formula is halophos 1200 times +5% aminooligosaccharide 600 times +3% acetamiprid+1200 times.
Personal recommendation of late blight: propamocarb or cymoxanil+potassium dihydrogen phosphate, cyanohydrin+potassium dihydrogen phosphate, or fluazinam+ethylicin+potassium dihydrogen phosphate are used alternately for prevention and control.
Early blight. It is suggested that propamocarb, iprodione, bendazole or azoxystrobin should be combined with spraying, and the drug should be used alternately every five days 1 time for three times.
Umbilical rot caused by calcium deficiency. You can spray brassinolide+liquid calcium or chelated calcium +0.2% acetic acid. Acetic acid and calcium form soluble calcium acetate, which is more conducive to the absorption of calcium.
The harm of whitefly can be controlled by spraying one or two of ethyl spinosad, nitenpyram, pymetrozine, imidacloprid, acetamiprid, thiamethoxam or veratrum.
Helicoverpa armigera and Spodoptera litura can be controlled by Bacillus thuringiensis or polyhedrosis virus insecticide or emamectin benzoate, tebufenozide or avermectin difluoride or monosultap, florfenicol or indoxacarb or Sinochem 9080. Recommended formula: Bacillus thuringiensis from big companies or emamectin benzoate+Sinochem 9080+ silica gel spray for 2-3 times, with an interval of 5-7 days each time!
Avermectin can control liriomyza sativae.