벼 극만식재배에서의 赤枯發生과 그 遺傳

Rice leaf discoloration in latest season planting and its inheritance

Rice leaf discoloration in latest season planting under field condition proposed as a screening method for cold tolerance and its mode of inheritance detected here. The salient findings were summarized as follows; Rice leaf discoloration in latest season planting showed from the begining of cool temperature below margin to just before frost falls under field condition at adult stage. Components value, showing the dispersion of population, in rice leaf discoloration of 44 genotypes at weekly reading under two different condition indicated appropriate time to distinguish varietal difference. Highly significant correlation(r=0.7536) recognized between adult stage in latest season planting under field and seedling stage under cool water tank. Clear difference in rice leaf discoloration recognized among varietal groups. Indica having cold tolerance and Tongil type rice showed more greater degree and variance value in leaf discoloration than that of Japonica rice. Any significant varietal difference in leaf discoloration could not recognize in the Japonica rice. Based on the screening test, Milyang 83 as susceptible parent, and Iri 371, IR20654-RRR-15-1 as resistant parents were selected, then crossed reciprocally to detect inheritance mode of leaf discoloration. The mode of inheritance for rice leaf discoloration revealed that resistant characteristics was showed to be partial dominance, and the maternal effects could not be recognized.