POTASSIUM APPLICATION REDUCES BARENESS IN DIFFERENT MAIZE HYBRIDS UNDER CROWDING STRESS CONDITIONS

Higher yield in different maize hybrids is obtained simply by increasing the plant density, but it is not so simple that by increasing plant density would multiply the grain yield through many folds. There is a certain limit where increase in plant density tends to stabilize the grain and biological yield and it tends to decline. For this purpose, an experiment was conducted on a sandy clay loam soil and designed in randomized complete block design with split plot arrangement with four replications, randomizing maize hybrids in main plots (H1= Pioneer-3012, H2= Pioneer-3062, H3= Pioneer – 30D55) and plant density levels P1 = 15 cm x 70 cm (95238 plants ha-1), P2 = 25 cm x 70 cm (57142 plants ha^-1), and P3 = 35 cm x 70 cm (40816 plants ha^-1) with K application (K0=0, K1=100, K2=150, K3=200 and K4=250 Kg ha^-1) . It was observed that plant bareness tends to increase with the increase in plant density with widening of period between tasseling and silking time, which resulted in less number of grains, grain rows cob^-1 and produced less grain weight cob^-1 and vice versa. Pioneer-30D55 was the most resistant hybrid to plant bareness as compared to Pioneer-3062 and Pioneer-3012. Potassium application definitely reduced plant bareness among all three hybrids. Pioneer-30D55 was the most responsive hybrid as compared to Pioneer-3062 and Pioneer-3012. Potassium application increased fertilization by adjusting the period between tasseling and silking which resulted in more number of grain rows, grain cob^-1 and produced higher grain weight cob^-1, when crop was fertilized from 100 to 200 Kg ha^-1, and then it tended to decline. It is therefore suggested that Pioneer-30D55 should be preferably grown at plant density of 95238 plants ha^-1 to explore maximum production potential with K application 200 Kg ha^-1 to avoid plant bareness due to crowding stress.