Remedial measures for deficiency of watermelon with yellowing leaves and limited growth

Deficiency of watermelon

First, calcium deficiency: when the watermelon is deficient in calcium, the apical growth is blocked, often showing symptoms in the new parts such as terminal buds and root tips; the leaves are yellow and curly, and the top leaves turn brown and die; fruit pedicel indentation, cracking, brown rot and even necrosis, forming navel rotten fruit. Remedial measures: first, adding gypsum powder or calcium-containing fertilizer such as calcium superphosphate, etc.; second, foliar spraying 0.2%-0.4% calcium chloride solution.

Second, magnesium deficiency: when watermelons are magnesium deficient, the first symptoms are the old leaves. The veins near the main veins of the old leaves fade green and yellow, but the veins are still green, and then gradually expand, so that the whole leaf turns yellow, resulting in death. Most of them start from the old leaves at the base and gradually develop upward. In severe cases, the leaves of the whole plant are yellow and green. Remedial measures: when magnesium deficiency is found, 0.1% magnesium sulfate solution is sprayed on leaves in time.

Third, boron deficiency: when the watermelon is boron deficient, the new vine internodes become shorter, the vine tip is upright, the growth point is restrained and whitish; the leaf is small, the leaf surface is wrinkled, the edge is curled downward, and the leaf is parachute-shaped; flowers are few or not flowering, floral organ development is poor or deformed, difficult to sit melon, after sitting melon, deformed melon or hollow melon. Boron deficiency in watermelon is easy to be misdiagnosed as virus disease, but there is no disease center of boron deficiency in watermelon, while virus disease has disease center and spreads in all directions. Remedial measures: when boron deficiency is found, 0.1%-0.2% borax solution is sprayed on the leaves.

Fourth, iron deficiency: when watermelon is iron deficient, it first shows symptoms on the top tender leaves. In the early stage or when the iron deficiency is not serious, the apical new mesophyll is green or yellowish, and the leaf veins remain green. With the delay of time or severe iron deficiency, the leaf veins become green or disappear, and the whole leaf is yellow or yellow-white. Remedial measures: when iron deficiency is found, ferrous sulfate is sprayed on the leaves with 500 / 1000 times solution.

Fifth, zinc deficiency: when watermelon is zinc deficient, the branches are slender, the internodes are short, the leaves are poorly developed, the leaves are small in clusters or rosettes, roll to the back of the leaves, and the leaf tips and margins turn brown and scorch gradually. Remedial measures: zinc deficiency symptoms can be foliar spraying EDTA-Zn fertilizer, generally diluted 2000-3000 times.

Sixth, manganese deficiency: when watermelon is deficient in manganese, the young leaves are yellowed, and the main veins are still green, and then develop to just mature leaves, seeds are underdeveloped, and deformed fruits are easy to form. Remedial measures: when manganese deficiency is found, 0.05%-0.1% manganese sulfate solution is sprayed on the leaves.