耐低钾冬小麦基因型筛选方法的研究

STUDY ON METHOD FOR SCREENING WINTER WHEAT GENOTYPES TOLERANT TO LOW POTASSIUM LEVEL

通过液培实验及低钾土壤上的田间实验，比较、讨论了耐低钾冬小麦基因型的筛选指标、时期及钾浓度。结果表明：液培筛选的评价指标，吸钾量优于钾利用指数。筛选的适宜时期为拔节期，钾浓度以10mmol／LK+为宜。低钾土壤上7种基因型的经济产量与植株地上部吸钾量间存在极显著正相关（r＝0.945，n＝21）。冬小麦吸收的钾主要来自于1mol／L热HNO3不能提取的非交换性钾。吸钾量亦可作为田间筛选的评价指标。

Methods for screening winter wheat genotypes tolerant to low potassium level were studied by water cultllre and field experiments on a soil of low potassium fertility. It was observed that the amount of K absorbed was better than potassium utilization index when used as the screening index. The 1.0mmol/L K concentration of the medium was found to be the suitable index at jointing stage of the plant. There was a sigificantly positive correlation between grain yield and the K content of shoot for 7 genotypes of winter wheat on the low-potassium soil（r=0.945， n= 21）. The amount ot K absorbed by winter wheat was most from the non-exchangeable K of the soil that can not be extracted with 1mol／L hot HNO3 was the largest. The amount of K absorbed by winter wheat could also be used as a field screening index.