干旱胁迫下春小麦品种(系)萌发期抗旱性鉴定与评价

Identification and Evaluation of Drought Resistance of Spring Wheat Varieties(Lines)at Germination under Drought Stress

干旱是影响小麦萌发及生长的制约要素之一,直接影响小麦生长发育和产量建成。为了探究小麦种子萌发期对干旱胁迫的响应,并对其相应品种进行萌发期抗旱性评价,本研究选取70份春小麦材料,采用20%PEG-6000溶液模拟干旱条件,分别测定对照处理下和干旱胁迫处理下不同春小麦品种的发芽势、发芽率、初生根数、胚芽鞘长度、主胚根长以及干物质量等指标,进行主成分分析,并通过加权隶属函数法得出综合抗旱指数(D值)。结果显示:干旱胁迫处理后小麦的发芽势、发芽率、初生根数、胚芽鞘长度、主胚根长以及干物质量均受到抑制,其中发芽势降幅范围为0%~11.7%,发芽率降幅范围为0%~43.71%,初生根数降幅范围为0.60%~64.16%,胚芽鞘长度降幅范围为0.31%~74.09%,主胚根长降幅范围为1.36%~75.81%,干物质量降幅范围为2.71%~65.82%;主成分分析法将6个单项指标转换为2个新的相互独立的综合指标;D值变化范围为0.22~0.98,其中‘南大96-4936’、‘ID6-110’、‘永4364’、‘40IBWSN’、‘宁春35号’、‘永1620’抗旱性评价为强抗(1级),V16(‘洛24318’)等20个品种抗旱性评价为中抗(2级),V1(‘青春556’)等42个品种评价为弱抗(3级),V5(‘9SEN21’)和V6(‘武春1号’)评价为干旱敏感型(4级)。本研究以期为萌发期的抗旱性鉴定和抗旱小麦品种的选育提供参考。

Drought is one of the restrictive factors affecting the growth and germination of wheat which directly affects wheat development and yield.In order to explore the response to drought stress of seed germination period of the wheat,and evaluate the drought resistance of their corresponding varieties,in this study,70 spring wheat materials were selected and drought conditions simulated by 20% PEG-6000 solution.The germination potention,germination rate,radical number,coleoptile length,radicle length and dry matter weight of different spring wheat varieties under drought stress treatment were measured respectively.Principal component analysis is carried out for indicators,and the comprehensive drought index(D value)was obtained through the weighted membership function method.The results showed that the germination potention,germination rate,radical number,coleoptile length,radicle length and dry matter weight of wheat after PEG-6000 stress treatment were all inhibited,and the reduction range of germination potention was 0%~11.7%,the reduction range of the germination rate was 0%~43.71%,the reduction range of the radical number was 0.60%~64.16%,and the reduction range of coleoptile length was 0.31%~74.09%,the range of radicle length reduction was 1.36%~75.81%,the reduction range of dry matter weight was 2.71%~65.82%;principal component analysis method converts 6 individual indicators into 2 new independent comprehensive indicators;the D value varies from 0.22 to 0.98,among which’Nanda96-4936’,’ID6-110’,’Yong4364’,’40IBWSN’,’Ningchun35’,and’Yong1620’are rated as strong drought resistance(Level 1),the drought resistance of 20 varieties including V16(’Luo24318’)was evaluated as medium resistance(Level 2),42 varieties including V1(’Qingchun556’)were evaluated as weak resistance(Level 3),V5(’9SEN21’)and V6(’Wuchun1’)were evaluated as drought sensitive(Level 4).This study aims to provide a reference for the identification of drought resistance during the germination period and the breeding of drought-resistant wheat varieties.