春小麦穗发芽抗性鉴定及机理研究

The Resistance and Mechanism of Pre harvest Sprouting in Spring Wheat

对国内外 5 7个春小麦品种 (系 )开花后不同时期进行穗发芽抗性和α-淀粉酶活性的测定 ,用改进的凝胶扩散法测定小麦种子α-淀粉酶活性。结果表明 ,不同春小麦品种的抗穗发芽特性及α-淀粉酶活性具有明显差别 ,来自东北地区的大部分主栽品种的穗发芽抗性中等。总体上 ,红粒品种的穗发芽抗性比普通白粒品种强 ,在白粒品种中也存在抗性极强的品种。不同穗型对发芽率的结果影响不大 ,小麦品种的穗发芽抗性可以用开花后 35～ 40 d的籽粒发芽率为指标。不同品种的α-淀粉酶活性和降落值存在显著差异 ,穗发芽率与种子中α-淀粉酶活性呈显著正相关 ,与降落值呈显著负相关。开花 2 5～ 40 d期间 ,穗发芽总体上呈上升趋势 ,α-淀粉酶有下降趋势 。

The pre harvest sprouting resistance, the α amylase activities of 57 spring wheat varieties (lines) were determined in different periods after the anthesis. The results showed that there were obvious differences among the pre harvest sprouting resistances and the α amylase activities of these varieties. Most varieties of the northeast parts of China had only middle resistance to pre harvest sprouting. The pre harvest sprouting resistance of red color coat materials was higher than that of white materials,but there were highly resistant varieties among these white color varieties. Different spike types had little influence on the pre harvest sprouting rates. The grain germination rates during 35～40 d after the anthesis could be a scriterion of pre harvest sprouting resistance. There were significant differences among the α amylase activities. Pre harvest sprouting rates were highly positive correlated with the α amylase activities, whereas negatively correlated with the falling number. There was a tendency of increasing of pre-harvest sprouting rates and decreasing of α amylase activities during 25 d to 40 d after the anthesis.