옥수수 自殖系統과 F₁에 대한 登熟期間 및 登熟速度 比較

Comparison of duration and rate of grain filling among corn inbred lines and hybrids

In order to understand the effects of duration and rate of grain filling of corn inbred lines and hybrids, twenty eight corn hybrids from diallel crosses of eight inbreds were planted at Experimental Farm of Chungbook Provincial Rural Development Administration in 1988. Measurements for characters were made on the upper and the lower parts of the same ear. Lag period of kernel from upper part of the ear ranged from 11 to 15 days, while lag period of kernel from lower part of the ear ranged from 9 to 13 days in parental inbreds. In F₁, hybrids, the upper part of the ear showed 10 to 16 days of lag period and the lower part of the ear showed 9 to 12 days. Effective grain filling periods for the parents ranged from 19 to 30 days regardless of the ear position, and the average period was about 24 days. In F₁, the effective grain filling period was from 23 to 29 days in the lower part(average 26.3 days), and the effective grain filling period was from 20 to 31 days in the upper part(average 24.2 days). Mean difference of effective filling period was from 20 to 31 days in the upper part(average 24.2 days). Mean difference of effective grain filling period between the lower and upper parts of the ear was about 2.1 days, and the upper part of the ear was a few days shorter than the lower part of the ear. Total grain filling period in the upper and lower part of the ear of parental lines were about 40 days and 39 days, respectively, and in the F₁ these were about 42 days and 43 days, respectively, and in the F₁ these were about 42 days and 43 days, repectively. Days to black layer appearance in the upper and the lower parts of the F₁ were 41 and 42 days and 43 days, respectively. Days to black layer appearance in the upper and the lower parts of the F₁ were 41 and 43, respectively, and these were about one to 3 days later than the 40 days of parental lines. The latest days of black layer appearance for the F₁ were 49 days of FR2A/KS42 and the most quick days of black layer appearance for the F₁ were 47 days of A508/A662. The rate of grain filling during lag period of parents was 84㎎/100kernel (k)/day at the upper part and 107㎎/l00k/day at the lower part of the ears. The rate of grain filling during the lag period of F₁ hybrids was 101㎎/100k/day at the upper part and 142㎎/100k/day at the lower part. The rate of grain filling during effective filling period of parents was 700㎎/100k/day at the upper part and 814㎎/100k /day at the lower part of the ear. The rate of grain filling during the effective filling period of F₁ was 878㎎/100k/day at the upper part and 944㎎/100k/day at the lower part of the ear. The rate of grain filling of the F₁ was a little faster than that of the parental lines.