光合参数结合形态指标评价马铃薯响应低磷胁迫的品种间差异

Evaluation of Differences among Potato Cultivars in Response to Low P Stress by Combining Photosynthetic Parameters with Morphological Indices

磷是有限的自然资源,磷肥当季利用率低,而过量施磷则会加重农业面源污染风险。挖掘马铃薯自身磷高效遗传特性,培育耐低磷品种是节约磷资源和保护生态环境的重要途径。建立基于光合表型参数的马铃薯品种(系)耐低磷能力评价体系,可实现耐低磷马铃薯种质快速、无损、高效鉴定和选择。以20个马铃薯品种(系)为材料,以膨胀珍珠岩为基质,在正常磷营养液池(1.70 mmol/L NaH2PO4)和低磷营养液池(0.17 mmol/L NaH2PO4)中培养,测定各品种生物量、产量和光合表型相关指标,计算各指标耐低磷胁迫指数。利用综合隶属函数法,进行主成分分析、回归分析,对各马铃薯品种(系)进行耐低磷能力的划分,综合评价各马铃薯品种耐低磷能力。与正常磷相比,低磷胁迫下,供试马铃薯品种(系)的单株产量、植株总干重、根干重等指标的均值降幅较大,各指标变异系数范围为3.24%~132.99%;光合参数中非光化学淬灭系数qN、PSⅡ反应中心开放比率qL、非调节性能量耗散的量子产量?no等光合参数有所上升。对各项指标的耐低磷胁迫指数进行主成分分析,前5个主成分的累计方差贡献率达86.32%,利用隶属函数法计算耐低磷综合评价值(D),D值范围为0.3258~0.7702;采用多元回归分析方法,建立了马铃薯耐低磷预测模型,确定了5个耐低磷鉴定指标并进行系统聚类,将20个马铃薯品种(系)划分为耐低磷型、中间型、低磷敏感型3类,并筛选出红玫瑰、6-1、滇薯1520、丽薯6号、27-1、滇薯1208为耐低磷型品种,而86-2、滇薯1504的耐低磷能力较差,为磷敏感型。

Phosphorus is a limited natural resource,but the utilization rate of phosphorus fertilizer in the current season is low,and excessive application of phosphorus increases the risk of agricultural non-point source pollution.It is an important way to save phosphorus resources and protect the ecological environment to excavate the genetic characteristics of phosphorus efficiency and cultivate low phosphorus tolerance varieties in potato.The establishment of an evaluation system of low phosphorus tolerance of potato varieties(lines)based on photosynthetic phenotypic parameters can achieve rapid,non-destructive and efficient identification and selection of low phosphorus tolerance potato germplasm.A total of 20 potato varieties(lines)were cultured in normal phosphorus nutrient solution pool(1.70 mmol/L NaH2PO4)and low phosphorus nutrient solution pool(0.17 mmol/L NaH2PO4),and the biomass,yield and photosynthetic phenotype of each cultivar were measured.The low P stress tolerance index of each index was calculated.Using the comprehensive membership function method,principal component analysis and regression analysis,the low phosphorus tolerance of each potato variety(lines)was divided,and the low phosphorus tolerance of each potato variety(lines)was comprehensively evaluated.Compared with normal P stress,the average value of yield,plant dry weight and root dry weight of potato varieties under low P stress decreased greatly,with the coefficient of variation of each index ranging from 3.24%to 132.99%.The photosynthetic parameters,such as non-photochemical quenching coefficient(qN),open ratio of PSⅡreaction center(qL),and quantum yield of non-regulatory energy dissipation(ɸno),were increased.The cumulative variance contribution rate of five principal components was 86.32%.The membership function method was used to calculate the comprehensive evaluation value of low phosphorus tolerance(D),and the D value ranged from 0.3258 to 0.7702.Using multiple regression analysis method,the D value regression equation was established to predict potato low phosphorus tolerance.Five identification indexes of low phosphorus tolerance were determined by multiple regression analysis and systematic clustering was carried out.The 20 potato varieties(lines)were divided into three types:low phosphorus tolerance type,intermediate type,and low phosphorus sensitive type.Red rose,6-1,Dianshu 1520,Lishu 6,27-1 and Dianshu 1208 were selected as low P tolerant varieties,while 86-2 and 54-2 were poor in low P tolerance and were P sensitive varieties.