大田评价水稻耐盐碱性的农艺性状指标研究

Field Indexes of Agronomic Traits for Salinity Tolerance Evaluation in Rice

为选择合适的农艺性状指标用于评价水稻耐盐碱性,以日本晴、9311杂交衍生的127份染色体代换系为研究对象,通过滨海盐碱地大田试验,分析了水稻主要农艺性状在全生育期淡水灌溉(对照,CK)和咸水灌溉(盐碱胁迫,ST)处理下的变异规律。结果表明:亲本和染色体代换系的盐碱胁迫反应存在明显分化,不同农艺性状在CK和ST生境下的遗传率以及盐碱胁迫敏感性指数(SSI)分布有明显差异。其中,株高、穗重、百粒质量在2种生境下的遗传率较高且稳定,结实率、主穗颖花数在盐碱生境下的遗传率明显下降;主穗颖花数、株高、穗长、穗重SSI的标准差和变异系数较小,一次枝梗数、结实率SSI的标准差和变异系数较大。根据性状的遗传率和盐碱胁迫敏感性指数分布特征,株高、穗重、百粒质量等性状可以作为抗性指标,用于遗传分离群体中抗性株系的初选标准,一次枝梗数、结实率可以作为敏感性指标,用于抗性株系的再次评价,综合这些农艺性状可以作为水稻全生育期耐盐性鉴定指标。

In order to establish the appropriate agronomic trait for salinity tolerance evaluation in rice breeding,127 chromosome segment substitution lines(CSSLs),derived from a cross between Nipponbare and 9311,were cultured in the fresh water irrigation condition(control,CK)and the saline water irrigation condition(salinity treatment,ST)and were used to illustrate the pattern of agronomic traits variation in saline/alkali soil during full growth period.The results showed that the responses to salt stress were segregation significantly in parents and CSSLs population and the traits sharply contrasted in theirs heritability and the distribution of stress susceptibility index(SSI).Plant height(PH),panicle weight(PW)and 100-grain weight(GW)were proved with high and stable heritability,while spikelet fertility(SF)and No.of spikelets per panicle(SP)obviously decreased theirs heritability in ST.SP,PH,panicle length(PL)and PW were revealed more little standard deviation(s)and coefficient of variation(CV)in SSI.On the contrary,No.of rachis branches(RB)and SF performed relatively large s and CV in SSI.Based on the above results,PH,PW or GW was propitious to act as a criterion to screen salinity tolerant individuals in genetic segregation population,while RB or SF was conducive to deal with the salt susceptibility of selected individuals again.The above mentioned traits could be used as ones of full growth period indexes for salinity tolerance screening in rice.