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Second, the protection of stems and leaves do not turn over sweet potato turning because stems and leaves are damaged, reduce photosynthesis, produce less nutrients, resulting in reduced production, while turning the leaves will also cause the leaves to flip overlap, dense, damage the top of the dome, to promote the emergence of new shoots buds And leaflets, resulting in reduced production, up to 20% to 30%.
Third, timely prevention and control of pests and diseases In recent years, sweetpotato larvae occur heavier, if found should be promptly sprayed with 4.5% beta cypermethrin EC 3000 times, or 20% cypermethrin 2000 times for prevention, to ensure that sweet potato has enough leaf area At the same time, it is necessary to prevent and control aphids in time to prevent the introduction of viruses.
First, to prevent the growth of stems and leaves summer sweet potato season is in high temperatures, rain and more seasons, stems and leaves growing rapidly, if not timely control, prone to prosperous. When the sweet potato scorpion grows to 50-60 centimeters, 10 ml per 667 square meters is sprayed, or 20 to 25 milliliters of auxiliaries. For fertilizer-deficient seedlings, 10 kg of urea or 20 kg of diammonium phosphate is chased every 667 square meters, and 1,000 kg of excrement and urine is chased and acquainted. The method is to open a hole next to the ridge back. Water after fertilization, water infiltration immediately covered soil.