多穗多蘗性 옥수수 硏究 Ⅰ. 栽植密度가 多穗多蘗性 交雜種 1K × IRI의 主要特性에 미치는 影響

Studies on the maize with multiple ears and tillers(MET) Ⅰ. Effects of plant densities on the major characteristics of MET hybrid 1K × IRI

Agronomic and morphological characteristics of a maize hybrid (IK × IRI) with multiple ears and tillers were evaluated under different planting densities. The genetic capacity of producing tillers and ears per plant was confirmed under different planting densities. The average number of tillers per plant in IK × IRI was 3.8 irrespective of plant densities, while the Suweon 19, check hybrid, showed no tillers. In IK × IRI hybrid the average number of effective tillers per plant tended to increase as the plant densities decreased. The number of effective ears seemed to increase as the plant desities decreased from 70cm X 30cm to 70cm X 50cm. The leaf area index of the IK × IRI 90 days after sowing at the density of 70cm X 30cm and 70cm X 50cm were 6.27 and 5.66, respectively, while those of Suweon 19 were 3.98 and 2.50. The fresh and dry weight of the IK × IRI measured at different growing stage were exceeding those of check hybrid in later part of growth. Grain yield of the IK × IRI hybrid at densities of 70cm X 30cm and 70cm X 50cm were 652kg and 549kg per 10a, respectively. However, the grain yields of Suweon 19 were much higher than those of the IK × IRI hybrid. The 100 kernel weight of the IK × IRI hybrid was 15gr and the Suweon 19 33gr. The IK × IRI hybrid more resistant to black streaked dwarf virus than the Suweon 19 and the ear height of the IK × IRI hybrid was higher than the check hybrid.