叶片逆向衰老小麦及其生物学特性

Inverted Senescing Sequence of Wheat Leaves and Its Biological Characters

探讨叶片逆向衰老小麦的生物学特性,为高产小麦育种研究提供参考。2006-2011年连续5年进行了小麦叶片逆向衰老顺序和正常衰老顺序的比较试验,对冠层温度和一些重要生物学参数进行了测定。具有逆向衰老现象的小麦即叶片逆向衰老小麦的冠温、叶温、千粒质量的变化和正常衰老小麦明显不同,其冠层较冷且结实后期倒二叶的叶温低于旗叶,千粒质量大于正常衰老小麦,且增幅明显。其正置茎顶三叶叶色、叶绿素含量的变化规律与正常衰老小麦相似,倒置茎则明显不同。在接近乳熟后期时倒置茎旗叶叶色等级高于倒二叶;叶绿素含量表现为倒二叶>旗叶>倒三叶,并持续到小麦成熟。自然界存在小麦的逆向衰老现象,这类小麦倒置茎上旗叶的衰老先于倒二叶,且与此现象关联的生物学参数均发生了异常的变化。

The biological characteristics of inverted senescing sequence of wheat leaves were investigated.The study arranged comparative experiments of wheat materials presenting inverted and conventional leaf senescing sequences with the measurements of canopy temperature and some important biological parameters between 2006-2011.There was a type of wheat that presents an inverted leaf senescing sequence differing from the conventional leaf senescing sequence of the majority of wheats in nature,i.e.,its canopy temperature is lower and the temperature of 2nd leaf is lower than flag leaf′s.The 1000-kernel weights of the inverted sequence wheats were higher than that of common wheat and significant difference was observed.Moreover,the variation pattern of the topmost leaf color and chlorophyll content of conventional sequence stem were similar to that of common wheat,but the inverted sequence stem′s was contrary.The color rank of flag leaf was higher than the second leaf since the last stage of milk within the leaf-color inversion stem;the chlorophyll content of the second leaf was higher than that in top-three leaf along with the progress of growth,moreover,this phenomenon continued to wheat mature.The inverted senescing sequence of wheat leaves has been discovered in nature,the senescence process of the flag leaf was faster than the second leaf within the leaf-color inversion stem,and these biological parameters related to this phenomenon induced abnormal changes.