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Apply one-third of N and whole of P and K at the sowing time. The basal dose of N, P and K should be applied bands 5 cm to the side and 5 cm deeper to the seed. The remaining 2/3 of N should be applied in two equal splits, one at knee-high stage of the crop (40-45 days after sowing) and another at pre-tasselling stage. In low hill sub-montane areas, apply 1/8 N at the time of sowing, 3/4 N at knee-high stage and 1/8 N at tasselling stage. The second and third dose of N should be applied 10-15 cm to the side of the rows and raked properly. Under rainfed conditions, in case nitrogenous fertilizers are not available at sowing time, 1/3 N CAN be applied 2-4 weeks after sowing with first hand weeding and remaining 2/3 N CAN be applied at knee-high and pre-tasselling stages. Earthing up of soil may also be followed for better incorporation of fertilizer in the soil. In areas where lodging of the crop due to wind is a common feature, the late application of N may counteract adverse conditions by slowing down the growth. Application of zinc sulphate @ 25 kg/ha has been found beneficial in coarse textured soils of Una and Indora area.
In maize-wheat rotation, the application of FYM to maize only and that of phosphatic fertilizer to wheat only may be more beneficial in high rainfall areas. The continuous application of P fertilizer without FYM to maize may accentuate zinc deficiency.
If zinc deficiency symptoms have been observed in the previous crop or soil test data indicating low available Zinc, 25 kg zinc sulphate/ ha may be added before sowing of the crop. But is should not be mixed with any fertilizer at the time of application. In case, the zinc deficiency is noted in the standing crop, foliar application of zinc sulphate @ 0.5 per cent (5 kg zinc sulphate and 2.5 kg calcium hydroxide/hectare) should be done. In order to facilitate the farmers and extension workers in recongnising zinc deficiency, symptoms observed on leaves are given below:
Two to three week old plants develop broad bands of white or light yellow colour stripes between mid rib and edges though the leaf tip still remains normal green. In extreme deficiency cases, young leaves unfolding in the bud appear white and light yellow and hence called white bud disease of maize. At the age of 25-35 days, 4 th , 5 th and 6 th basal leaves also develop white patches on both sides. A distinctive feature of zinc deficiency in maize is that even in worst affected leaves, the margin and upper third portion of the leaf is greener than rest of the leaf lamina.
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