Nodulation and Early Growth of Supernodulating Mutants in Soybean

초다 근류착생 돌연변이체 콩의 뿌리혹 형성 및 초기생육

Increase in nodulation and nitrogen fixation was achieved partly through the isolation of supernodulating soybean mutant plants. This experiment was conducted to compare nodulation, nitrogen fixation, and early growth characters of wild type 'Bragg' with those of its supernodulating soybean mutant, 'nts 382' and 'nts 246'. At 31 days after planting, nodule dry weight of nts mutants was 2.5 to 3.7 times greater than that of Bragg. Higher nodulation of nts mutants showed the reduced top growth, indicating that photosynthates might be translocated and used for nodule growth attached to the root system. Total acetylene reduction activity was higher in nts mutants than Bragg, whereas specific acetylene reduction activity of nts mutant was the half of that of Bragg. Mixture of nts mutants and Bragg did not affect nodulation characters each other, suggesting that factors affecting supernodulating characters exist inside rather than outside the root system.

초다 근류착생성 콩 nts 382 및 nts 246와 wild-type인 Bragg의 초기생육, 뿌리혹 형성 및 질소고정능력을 조사하였으며, 그 결과는 다음과 같이 요약된다. 1. nts 계통은 뿌리혹건물중이 현저히 높아서 파종후 31일째에는 Bragg에 비하여 2.5내지 3.5배에 달하였다. 2. nts 계통은 과도한 뿌리혹 형성 때문에 지상부 광합성산물을 많이 소모하여 지상부의 생육이 저해되었다.