基于叶片解剖结构的京津冀主栽板栗品种抗旱性评价

为探究板栗品种的抗旱性评价方法,以36个京津冀主栽板栗品种的叶片为材料,结合叶片保水力的测定,采用多功能图像分析法、冷冻切片法和指甲油印记法,对21项抗旱相关解剖结构指标进行了观测,运用方差分析、主成分分析法对这些指标进行了筛选,运用隶属函数法对各品种的抗旱性进行了综合评价。结果表明,21项抗旱相关指标中有18项在36个板栗品种间存在极显著性差异(P<0.01),经主成分分析进一步从18项指标中筛选出6项典型抗旱指标,即叶片厚度、栅栏组织厚度、单位面积气孔总周长、叶柄长、上表皮细胞厚度和叶脉间距。按照隶属函数法结合6项典型抗旱指标及权重计算各品种抗旱性度量值(D),将36个品种划分为5类不同抗旱等级:高抗旱类型(HR)有4个品种,D值为0.60~0.80;抗旱类型(R)有10个品种,D值为0.50~0.59;中抗旱类型(MR)有13个品种,D值为0.30~0.49;低抗旱类型(LR)有6个品种,D值为0.20~0.29;不抗旱类型(S)有3个品种,D值为0~0.19。依据抗旱性度量值对36个板栗品种划分的抗旱性等级与采用叶片保水力的评价结果较为一致。本研究为京津冀主栽板栗品种的抗旱性等级划分与科学利用提供了依据。

Drought Resistance Evaluation Based on Leaf Anatomical Structure of Major Chestnut Cultivars in Beijing-Tianjin-Hebei Region

To explore the evaluation method of drought resistance of Chestnut cultivars. In this study, 21 anatomical structure indexes of 36 chestnut cultivars were measured by using multi-function image analysis, frozen sectioning and nail oil seal method combined with the determination of leaf water retention capacity. Leaf anatomical structure indexes were screened by variance analysis and principal component analysis, and comprehensive evaluation on drought resistance of each cultivar was conducted by the subordinate function.The results showed that 18 anatomical structure indexes of the 21 indexes all reached extremely significant differences among the 36 cultivars (P<0.01), and 6 typical indexes including leaf thickness, thickness of palisade tissue, the total stoma perimeter per unit area, petiole length, thickness of upper epidermis cell and spacing length of veins were selected from the 18 indexes by principal component analysis. The drought resistance level of 36 cltivars were divided into 5 types according to the measurement value of drought resistance (D)calculated by the membership function method combined with 6 typical indexes and their weights, 4 cultivars were divided into high drought resistance types(HR),the D value ranged from 0.60 to 0.80; 10 cultivars were divided into drought resistance types(R), the D value ranged from 0.50 to 0.59; 13 cltivars were divided into medium drought resistance types(MR), the D value ranged from 0.30 to 0.49; 6 cltivars were divided into low drought resistance types(LR),the D value ranged from 0.20 to 0.29; 3 cltivars were divided into susceptible types(S),the D value ranged from 0 to 0.19. The classification of 36 chestnut cultivars based on the drought resistance measurement were consistent with the evaluation of leaf water retention. This study provided basis for the drought resistance type division and scientific utilization of chestnut cultivars in Beijing-Tianjin-Hebei region.