影响不同种皮颜色小麦种子休眠的生理原因

Effects of Physiological Factors on Dormancy of Different Seed Coat-Colored Wheat Varieties

为了解小麦种皮颜色和休眠性的关系,分别选取红皮和白皮小麦品种各15个,测定其种皮颜色和休眠水平,对影响不同种皮颜色小麦种子休眠差异的生理原因进行分析。结果表明,基于数码相机图片提取的RGB数值推导出的指标色调(H)、饱和度(S)和强度(I)均可反映小麦种皮颜色的深浅度。R、H、S和I值与种子休眠性呈显著负相关,R/(R+G+B)与籽粒休眠性呈显著正相关,即籽粒种皮颜色越深,其休眠性越强(P<0.05)。红皮与白皮品种中均存在休眠差异性显著的材料。选取白皮小麦敏感性品种华成麦1688(W1)和抗性品种安农0711(W15)及红皮小麦敏感性品种白湖麦1号(R1)和抗性品种扬麦27(R15),进行生理性状分析发现,在种子萌发过程中,敏感性品种W1和R1的种子吸水率、含水量及α-淀粉酶、β-淀粉酶和酸性磷酸酶活性高;同时种子内部可溶性糖含量和蛋白质含量高;赤霉素(GA_(3))含量逐渐上升,而脱落酸(ABA)含量逐渐下降。反之,抗性品种W15和R15种子的淀粉酶活性及可溶性糖、可溶性蛋白和GA_(3)含量在休眠解除过程中低,ABA含量高。相同敏感性材料中,白皮小麦品种吸水速率和含水量均高于红皮小麦品种,整体趋势表现为W1>R1>W15>R15趋势。种子内部可溶性糖含量、蛋白质消耗量和GA_(3)含量表现出相同趋势;而ABA含量恰好相反,表现为R15>W15>R1>W1。在育种过程中,R、H、S、I值可以用来快速鉴别红皮和白皮小麦,间接辅助筛选出抗穗发芽品种,含水量、α-淀粉酶活性、β-淀粉酶活性、酸性磷酸酶活性、可溶性糖含量和ABA含量可作为穗发芽抗性鉴定的生理参考指标。

In order to understand the relationship between seed coat color and seed dormancy of wheat, 15 red and 15 white wheat varieties were selected to determine their seed coat color and dormancy level, and the physiological factors affecting seed dormancy of wheat were analyzed. The results showed that the index hue(H),saturation(S) and intensity(I) derived from RGB values extracted from digital camera images reflect the depth of seed coat color. The values of R,H,S and I were negatively correlated with seed dormancy(P<0.05),and R/(R+G+B) was significantly positively correlated with seed dormancy(P<0.05).There were significant dormancy differences between red and white wheat varieties. A sensitive variety Huachengmai 1688(W1) and a resistant variety Annong 0711(W15) of white wheat, and a sensitive variety Baihumai 1(R1) and a resistant variety Yangmai 27(R15) of red wheat were selected for physiological analysis.It was found that the water absorption, water content, the activity of α-amylase, β-amylase and acid phosphatase, the contents of soluble sugar, protein and gibberellin(GA_(3)) in the sensitive varieties(W1 and R1) were higher than those in the resistant varieties(W15 and R15).However, the content of abscisic acid(ABA) in the sensitive varieties was lower than that in the resistant varieties during the release of dormancy. Compared to the same sensitive materials, the water absorption and water content in white wheat varieties were higher than that in red wheat varieties, and the overall trend was W1>R1>W15>R15. The soluble sugar content, protein consumption and GA_(3)content in seeds showed the similar trend, while the comparison of ABA content in seeds was opposite, ranking as R15>W15>R1>W1. As a consequence, R,H,S and I values can be used to quickly identify red and white wheat varieties, which indirectly assist the screening of pre-harvest sprouting resistant varieties. The physiological indicators, i.e. the water content, the activity of α-amylase, β-amylase and acid phosphatase, the content of soluble sugar and ABA,can be used as the reference index for identification of pre-harvest sprouting resistance.