杂交水稻功能叶片叶绿素SPAD值的杂种优势分析

为探讨杂交水稻3片功能叶叶绿素SPAD值的杂种优势及杂种优势与双亲表现型值、双亲一般配合力(GCA)、组合特殊配合力(SCA)、双亲遗传距离(欧氏距离)等的关系,用5个不育系和5个恢复系,按不完全双列杂交配制25个组合。结果表明:供试组合3片功能叶叶绿素SPAD值具有一定的超亲优势,以乳熟期倒三叶叶绿素SPAD值的正向超亲优势组合最多,其次是始穗期的剑叶;供试的大多数组合除乳熟期倒二叶,不同生育期不同叶位叶片SPAD值都具有正向对照优势,特别是始穗期剑叶供试的25个组合都具有正向超亲优势;供试组合不同生育期不同叶位叶片叶绿素SPAD值的杂种优势大多与父本的表现型值、双亲平均值、低亲值、高亲值、特殊配合力、父本的一般配合力、父母本一般配合力之和显著或极显著相关;供试组合3片功能叶叶绿素SPAD值的超亲优势和对照优势与遗传距离相关不显著,但当遗传距离在13.0～18.0之间时,乳熟期剑叶叶绿素SPAD值的超亲优势与遗传距离呈显著正相关,对照优势与遗传距离呈极显著正相关,分蘖高峰期倒1叶和始穗期剑叶也与遗传距离呈正相关,但不显著。

Heterosis for Chlorophyll SPAD Value of the Last Three Leaves of Hybrid Rice

In order to explore the relation between heterosis of the chlorophyll SPAD value for the last three leaves and parents value,the general combing ability of parents（GCA）,the specific combing ability of combinations（SCA） and the genetic distance（Euclid distance）,5 male sterile lines（maintenance line）and 5 restorer lines were used to make 25 crosses by NC 11 design to analyze heterosis of chlorophyll SPAD value for the last three leaves.The results showed：Particular over parent heterosis was presented on chlorophyll SPAD value of the last three leaves.It was the most combinations with positive over-parent heterosis for chlorophyll SPAD value of the third from the end leaf at milk stage,next was flag leaf at initial stage of panicle emerging.There was contrast positive heterosis for the last three leaves of most test combinations except the second from the end leaf at different growth period.Particularly,there was positive contrast heterosis for flag leaf of all test combinations.There was significant correlation or very significant correlation between contrast heterosis and male parents value,average value of parents,low parent value,high parent value,the specific combing ability of male parents and the sum of general combing ability of female and male parents.There was no significant correlation between heterosis and genetic distance chlorophyll SPAD value of the last three leaves.However,at the distance 13.0~18.0 between two parents,it was significant positive correlation for over-parent heterosis and the genetic distance for chlorophyll SPAD value of flag leaf at mild stage.It was very positive significant for contrast heterosis and genetic distance at milk stage.It was positive correlation for the last leaf at active tillering stage and flag leaf at initial stage of panicle emerging,but it was not significant.