In production practice, many planting tomatoes farmers will encounter this problem, tomato stalks black, the onset of light plant growth is slow, weak, yield decline; serious plant wilting directly withered and died. Because of the tomato “black culm” has many reasons, if you can not treat the symptoms of the disease is difficult to get effective prevention and treatment. Therefore, many farmers and friends of tomatoes “black culm” disease headache.
Tomato “black stalks” according to the onset of the site can be divided into two kinds, one is the base of the stem appears brown and black, the other is the upper part of the stalks or fork at the black and brown spots, etc..
First, the base of the stem “black culm”. Usually, tomato stem base “black culm” is caused by stem rot, Phytophthora root rot of the two diseases.
Stem basal rot, also known as seedling blight, the identification of the key point of the disease is the base of the stem spot around the stem week, constriction, the late visible light brown spider-like mold, the plant gradually wilted and died. Prevention and control of the disease can be 20% of the methyl lincroft phosphorus emulsion 1200 times mixed with 95% of the green henry one (oxamylin) 3000 times solution for root irrigation.
Epidemic mold root rot, the stem base produces deep brown spots, gradually expand around the stem week, the spot is sunken, and stem rot disease is different, longitudinal dissection of the stem base can be seen in the conduit brown, while the stem rot disease is not. Prevention and control of the disease can be 72.2% of the Pricer 800 times mixed with 50% of the DT 500 times mixed with 80% of the Jinnahai (Fumitsu) 750 times liquid for root irrigation.
Second, stalks or branches at the “black culm”. Stalks or branches at the “black culm” is usually caused by tomato early blight, late blight, stem blight, streak virus disease, several diseases.
Early blight, irregular brown spots on the stalks or branches, black mold when humidity is high. In late blight, the stalks or branches become thin and dark brown, and the diseased fruits have obvious cloudy spots. The main drug for early blight is Manganese zinc diclofenac, while the main drug for late blight is mefenoxam, so the two diseases can be controlled by directly spraying 68% of Goldendomil (fine mefenoxam + Manganese zinc diclofenac) 800 times solution.
Stem blight, oval brown spots on the stalks, up and down expansion, later spots can be invaded into the vascular bundles, caused by the disease of the same pathogenic bacteria and early blight, are eggplant streptomyces, the control of the same diclofenac manganese zinc as the main drug, in addition to the spraying of gold Leiduo Mier, but also sprayed with 50% of the pohypnol wettable powder 1,000 times solution.
Stripe virus disease, stalks produce black-brown plaques, and stem blight is different from the onset of the site is more in the plant near the growing point, and the discoloration of the spot occurs only in the epidermis, will not go deep into the vascular bundles, which is the key to the difference between the two. Prevention and control of the disease, need to be sprayed in the early stage of the onset of 2% of the ninamycin water 500 times solution, or 20% of the virus A wettable powder 500 times solution.
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Post time: Mar-04-2024