Abstract: In order to evaluate the soybean genotypes tolerant to low potassium(K) stress,and to screen the high tolerant germplasms,seventy-two varieties from Hebei soybean-growing areas were identified with different potassium concentrations at seedling stage.The results showed that the 0.01 mmol/L could be the concentration for potassium-deficiency determination,and the 2.50 mmol/L for potassium-normal concentration in supplied solution.The relative values,ratios of weight in low K and weight in adequate K of shoots or roots,could be used as the screening indices.There were significant difference among 72 varieties in two different screening regimes(0.01,2.50 mmol/L).According to the relative indices of shoot and root weights,five soybean varieties were screened out for their high tolerance to low potassium stress.In addition,the protective enzymes of different potassium tolerant varieties showed that the difference of potassium nutrient effective types can be expressed by the protective enzyme systems.The screening results of soybean germplasms and the relationship between low-K tolerance and protective enzymes can be used to clone more K-efficiency genes,study the mechanisms of plant high K-efficiency and breed high tolerant varieties to low K stress.

Key words: Soybean, Germplasm resources, Low potassium stress, Screening indices, Variety identification

CLC Number: 

• S565.1