石灰性土壤上大豆耐低铁品种的鉴定指标研究

采用盆栽试验,研究了45个不同铁效率品种生育期间新叶的叶绿素含量变化及收获后株高、单株荚重、单株粒重、单株生物量、百粒重、籽粒铁含量,以总结石灰性土壤上不同铁效率大豆品种叶片的黄化规律,确定不同铁效率大豆品种的鉴定指标。结果表明:根据叶片黄化规律,可将品种分为1级、2级、3级、4级。V2~V4期不同品种新叶平均叶绿素含量1级2级3级4级,差异达极显著水平;至R1期时,2级品种新叶已经复绿,而4级品种的植株已全部死亡;R1~R6期,1级与2级品种新叶平均叶绿素含量差异不显著,但2级3级4级,差异达极显著水平。不同铁效率类型品种平均株高、单株荚重、单株粒重、单株生物量均存在显著差异,1级、2级品种平均百粒重、籽粒Fe含量差异不显著;2级、3级、4级品种以上各性状平均值均达极显著差异。说明苗期为大豆叶片缺铁黄化的敏感时期,可将苗期和生殖生长期的叶绿素含量共同作为大豆铁效率鉴定指标,株高、单株荚重、单株粒重和单株生物量可作辅助鉴定指标。

Research on Identification Indexes of Fe-efficient Soybean Varieties in Calcareous Soil

In the pot experiments,45 soybean varieties with different Fe efficiency were used as materials,then young leaf chlorophyll content during growth period,and plant height,pods weight per plant,grain weight per plant,biomass per plant,100-seed weight,Fe concentration in grain after harvest were determined,for summarizing leaf yellowing rules for soybean varieties with different Fe efficiencies,and confirming appraisal indicators for Fe efficiency of soybean varieties.The results showed that,according to leaf chlorosis rules,these varieties were divided into four levels,including efficient,more efficient,more sensitive and sensitive.The average chlorophyll content of their young leaves from V2 to V4 stage were efficient ＞ higher efficient ＞ more sensitive ＞ sensitive,with significant difference;until R1 stage,young leaf of more efficient variety had recoverd green,while all sensitive varieties had been dead;during R1-R6 stages,there was no significant difference between efficient variety and more efficient variety,but more efficient ＞ more sensitive ＞ sensitive,the difference among them were very significant.The difference of plant height,pods weight per plant,grain weight per plant and biomass per plant among soybean varieties with different Fe efficiency were significant,100-seed weight,Fe concentration in grain among efficient and more efficient varieties were not significant;all traits above among more efficient,more sensitive and sensitive varieties were very significant.These results indicated that seedling stage is sensitive stage of leaf iron deficiency chlorosis,chlorophyll contents at seedling stage and reproductive stage are together taken as identification indexes of Fe-efficient soybean varieties,plant height,pods weight per plant,grain weight per plant and biomass per plant are taken as complementary identification indexes.