Causes and Treatment of Fruit Drop in Golden Pomelo During Rainy Weather
The main causes of fruit drop are the failure to thin flowers at an early stage and insufficient application of fertilizer after flower drop, and since golden pomelo is still in its physiological fruit drop period, appropriate spraying of foliar fertilizer can alleviate fruit drop. However, fruit drop is only one aspect; the series of diseases triggered by rainy weather is also a problem that cannot be ignored. At the present stage, golden pomelo anthracnose, brown rot phytophthora...
The main causes of fruit drop are the failure to thin flowers at an early stage and insufficient application of fertilizer after flower drop, and since golden pomelo is still in its physiological fruit drop period, appropriate spraying of foliar fertilizer can alleviate fruit drop.
However, fruit drop is only one aspect; the series of diseases triggered by rainy weather is also a problem that cannot be ignored. At the present stage, golden pomelo anthracnose, brown rot phytophthora disease, canker and others will break out simultaneously.
For the main diseases currently appearing, the following can be selected and used in rotation to control anthracnose: 70% thiophanate-methyl wettable powder at 800 times dilution; 80% Daconil M-45 wettable powder at 600 times dilution; 50% carbendazim wettable powder at 600 times dilution; to control brown rot phytophthora disease, Keyishuang at 1000 times dilution or Yishuangling at 1500 times dilution can be sprayed, focusing on the middle and lower parts and the fruit, and attention should be paid to pruning dead branches, picking out diseased fruit, and centrally disposing of fallen fruit and fallen leaves; for canker, 77% Keshade wettable powder or copper oxychloride at 600 times dilution can be selected.
Before spraying, diseased branches should be properly pruned, which can avoid contagion and enhance the efficacy of the pesticide. When spraying, it is best to choose clear weather. However, Lu Youli, a grower in Songkou Town, Meixian, believes that as long as it is not raining all day, a suitable time can be chosen to spray pesticide. Although the effect is not as good as on a sunny day, as long as the right timing is chosen, the effect is still quite obvious: "By the time it clears up, the disease has already spread, and it will be too late to regret not treating it earlier."