小麦种子物理参数和萌发阶段抗旱性关系的研究

为了解陕西省当前推广小麦品种的物理性状与萌发阶段抗旱性的关系,测定了模拟干旱胁迫下小麦种子相对发芽率和各项物理指标(RGB、Lab、HSB、灰度、长度、宽度、投影面积等),并运用相关分析、方差分析和回归分析等方法,对陕西省目前推广种植的18个小麦品种萌发阶段的抗旱性与物理性状的关系进行了综合分析。结果表明,基于宽度、R、G、B(HSB)、L、H、灰度值等物理指标对小麦种子萌发阶段抗旱能力的预测具有统计学意义,且G、B(HSB)、L、H、灰度值等颜色指标之间相关系数较高,均大于0.96。在这些物理指标和相对发芽率建立的回归模型中,以宽度和G值为参数建模最好,决定系数为0.575,达到极显著水平。以供试材料中的5个品种及陕西省推广种植的其他10个小麦品种进行验证,以宽度和G值为参数所建模型得到的相对发芽率与模拟干旱胁迫条件下实测到的相对发芽率吻合度达到86.7%,说明依据宽度和G值对小麦品种萌发阶段抗旱能力的筛选是可行的。

Relationship between Physical Parameters and Drought Resistance of Wheat Seed at Germination Stage

Drought is one of the most important environmental stresses influencing crop yield. In order to study the relationship between physical parameters of wheat seed and drought resistance at germination, the seed physical indexes, such as RGB, Lab, HSB, length, width and projection area of 18 wheat varieties from Shaanxi province were accessed with Seed Identification Software, then the relationship between the relative germination percentage under drought stress with the above seed physical indexes was analyzed through correlation analysis, variance analysis and regression analysis. The results showed that the physical parameters R,G,B(HSB),L, H, grey and width all were significant correlated with drought tolerance of wheat,and the correlation coefficients among the above physical characteristics were all more than 0.96.Among the regression models setted up for physical indicators and relative germination rate, the parametric modeling based on G and width of seed was the best,the determination coefficient 0.575, which was extremely significant. With other 15 wheat cultivars of Shanxi province for validation, the goodness of fit of the stepwise regression with the actual relative germination rate under drought stress was 86.7%, which suggested that it was feasible to screen drought tolerance of wheat at germination by using the width and G value of seed.