How to prevent and control rice stiff seedlings?

How to prevent and control rice stiff seedlings? Please guide the etiology of rice seedlings: lack of zinc in the soil, rice seedlings will not occur in different degrees. The rigid rice seedlings caused by zinc deficiency mostly appeared within 2-3 weeks after transplanting. At first, the base of the heart leaf turned green and whitish, and later irregular brown spots appeared on both sides of the midvein of the middle and lower leaves, and gradually expanded into reddish-brown strips, and in severe cases, the brown spots extended to the leaf sheath and stem. The occurrence regularity of disease spot on the plant generally appears in turn from the lower leaf to the upper leaf. The leaf emergence rate of zinc-deficient rice plant is slow, the heart leaf is short and narrow, the lower old leaf becomes brittle and drape, it is easy to break, the root system is aging, and the new root is few. The occipital distance of seriously diseased plants was shortened or dislocated, obviously dwarfed and clustered, few tillers, and uneven growth in the field. For the paddy fields with obvious zinc deficiency or zinc deficiency trend, the application of zinc fertilizer can reduce stiff seedlings. Basic application of zinc fertilizer, dipping in root and foliar spraying can be done. Before transplanting, 1-2 kg zinc sulfate per mu was applied in the field; 1% zinc oxide suspension was dipped in the seedling root during transplanting; and 0.1-0.2% zinc sulfate solution was sprayed once 3-5 days before transplanting and 5-7 days after transplanting. Click to get massive rice planting technology click to get massive grain planting technology