Prevention and Control measures of abnormal Maize Seedling with Yellow Leaf Albino, Purple Red and Yellow Green Seedling

Maize yellow leaf seedling

First, yellow leaf seedlings: at first, the leaves of corn seedlings are light green and gradually turn yellow. in severe cases, the whole leaves die, resulting in empty culms or protruding tips.

Causes: the seeds are not full, the seedlings are not strong; the sowing is too deep, the emergence is weak; the density is too high, which affects the growth; the soil lacks fertilizer.

Prevention and control measures: 1. Select good seeds before sowing, pick out blighted, mildew, bad and small seeds to ensure that the purity and purity of the seeds are more than 98%, and the germination rate is more than 90%. two。 Promote germination and sow seeds, using seed coating or soaking seeds with fertilizer and water. 3. At the right time, the seedlings, weak seedlings, diseased seedlings and field weeds were removed at the 4th leaf of maize 3Mel. 4. After the seedlings, nitrogen fertilizer was applied to promote the early growth and rapid development of seedlings. 5. If there is a dry clod before and after emergence, the dry clod should be broken in time.

Second, purple seedlings: seedling leaves, leaves from green to red, and finally purple, generally showing symptoms in the 3-leaf stage of maize, the most obvious in 4-Mel-5 leaves, the root system is underdeveloped, the stem is small, the growth is slow, the leaves change from green to purple, and the leaves die in serious cases.

The cause of occurrence: because of the lack of phosphorus in the soil, the absorption capacity of roots decreased and the synthesis of chlorophyll was blocked, resulting in the change of leaves from green to purple. After the emergence of maize seedlings, in case of low temperature, the leaves often make maize leaves turn red or purple, but with the height of the temperature, the phenomenon of red seedlings will gradually alleviate and disappear in the later stage. In addition, red seedlings can be caused by low-lying water in the field, harm by underground pests, heavy soil, too deep or shallow sowing, burning seedlings caused by improper fertilization and poisoning caused by improper chemical treatment.

Prevention and control measures: increase the application of phosphate fertilizer as base fertilizer, generally apply 40 Mu 50kg superphosphate and mature fermented organic fertilizer as base fertilizer. Once purple seedlings appear, 0.2% potassium dihydrogen phosphate can be sprayed on the leaves three times; leveling the land and digging drainage ditches, so that the rain stops dry and the fields do not accumulate water.

Third, yellow-green seedlings: maize seedlings have narrow leaves, short plant types, yellow-green stripes on the leaves, dark brown in severe cases, and finally scorched to death. The symptoms start from the lower leaves and gradually transfer to the upper leaves, which affects the yield greatly and is prone to lodging.

Cause: potassium deficiency in soil.

Control measures: increase the application of potassium fertilizer, those without potassium fertilizer can apply plant ash at the seedling stage, if the potassium deficiency is serious, spray the leachate with potassium dihydrogen phosphate or plant ash at the 3-leaf stage, the effect can be seen immediately, and the yield increase is obvious.

Maize albino seedling

Fourth, albino seedlings: generally from the four-leaf stage, the night color at the base of the new leaves becomes pale yellow-white, 5mur6-leaf stage, the third leaf under the heart leaf appears light yellow and light green stripes, but the vein is still green, the base appears purple stripes, after 10 color for 15 days, the purple gradually becomes yellowish white, the mesophyll becomes thin, showing a "white seedling", and in severe cases, the whole field is white. The zinc-deficient corn plant is short, the internodes are short, the leaf pillows overlap, the heart leaves grow slowly and look flat-topped, and the serious white leaves gradually dry up, even the whole plant dies.

Cause: zinc deficiency in soil.

Prevention and control measures: 1. Using zinc fertilizer as seed fertilizer, 1.5 kg of zinc sulfate per mu and 15 ml of 20 kg fine soil were mixed evenly and sprinkled beside the seeds when sowing corn. two。 Seed dressing with zinc fertilizer, seed dressing with 1kg zinc sulfate and 25kg corn seed. The method is to dissolve 1kg zinc fertilizer with 2ml 3kg warm water. After all the solution is dissolved, the zinc fertilizer solution is sprayed evenly on the corn seed, so that the seed surface is stained with zinc fertilizer, and the seeds are sown after drying. 3. Zinc fertilizer was sprayed on the leaves. For the seedlings with zinc deficiency, the seedlings were sprayed with 0.3 kg zinc sulfate and 100 kg water per mu, once every 7 days. Generally, the seedlings could be restored to normal by spraying 2 mi 3 times.

5. Zombie seedlings: it mainly occurs before the 3-leaf stage of seedlings, showing small seedlings, light green leaves, increased black roots and soft atrophy. After transplanting, except the new leaves are green, the outer leaves are yellow and stiff, the stress resistance is poor, and dead leaves and seedlings are easy to appear.

Causes: the soil is too hard; the proportion of chemical fertilizer is too large, which leads to root burning and sprouting, and the soil is too dry after sowing.

Prevention and control measures: reasonably adjust the conditions of fertilizer, water and gas. Corn seedling stage is mainly mature organic fertilizer, no or less urea as base fertilizer. Phosphate fertilizer should be applied after retting. The soil is suitable for humidity, and strong seedlings are transplanted. Rigid seedlings have emerged to strengthen fertilizer and water management, promote their recovery as soon as possible, and seriously replenish seedlings in time.