The responses of maize genotypes to growth conditions

Abstract

Studies on the effects of sowing densities on maize grain yields under irrigation were performed with the aim of creating favourable conditions for plant growth and development, under which the genetic yield potential would be maximally exploited. A two-factorial trial was performed in the period 2006-2009 on chernozem, according to the split- plot method with four replicates. Four maize hybrids of different FAO maturity groups (ZP 341, ZP 434, ZP 684 and ZP 704) were observed in combination with seven sowing densities (G1 - 40,816 plants ha-1, G2 - 50,125 plants ha-1, G3 - 59,524 plants ha-1, G4 - 69,686 plants ha-1, G5 - 79,365 plants ha-1, G6 - 86,286 plants ha-1 and G7 - 98,522 plants ha- 1). The obtained results showed statistically very significant differences in maize grain yields between the studied hybrids and the sowing densities. The lowest yields were recorded for all studied hybrids at the lowest sowing density (40,816 plants ha-1). The regression analysis indicated that, depending on a maize hybrid, the following maximum yields could be expected: ZP 341 - 13.25 t ha-1 at a sowing density of 81,000 plants ha-1, ZP 434 - 13.00 t ha-1 at a sowing density of 75,000 plants ha-1 , ZP 684 - 13.83 t ha-1 at a sowing density of 82,000 plants ha-1 and ZP 704 - 12,83 t ha-1 at the sowing density of 77,000 plants ha-1. In accordance with the rational use of seeds, high yields are obtained by sowing that provides 50,000 plants of ZP 434 ha-1, 60,000 plants of ZP 341 ha-1 and ZP 704 ha-1 and 70,000 plants of ZP 684 ha-1.