麦棉套作冬小麦灌浆期叶片光合生理特性研究  

Study on Physiological and Photosynthetic Characteristics of Winter Wheat Leaves Intercropped Cotton at Grain Filling Stage

作　　者：周新国[1] 陈金平[1] 刘安能[1] 

机构地区：[1]中国农业科学院农田灌溉研究所,河南新乡453003

出　　处：《麦类作物学报》2005年第2期33-36,共4页Journal of Triticeae Crops

基　　金：国家自然科学基金项目(50379054);"十五"国家科技攻关项目(2001BA508B02)。

摘　　要：在大田土壤水肥条件下,于灌浆期对麦棉套作冬小麦不同叶位叶片的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、叶肉细胞间隙CO2浓度(Ci)以及叶绿素含量做了连续测定,并对不同叶位叶片的籽粒贡献率做了分析,以研究麦棉套作条件下冬小麦的叶片光合生理特性。结果表明,小麦叶片的Pn和Tr在花后的变化趋势表现一致,且其大小顺序为旗叶(FL)、倒2叶(Cd2L)、倒3叶(Cd3L)、倒4叶(Cd4L)。随着叶片的衰老进程,叶绿素含量迅速下降,倒3叶和倒4叶主要为非气孔限制造成了光合衰退,旗叶和倒2叶前期为气孔限制,后期为非气孔限制,但旗叶非气孔限制引起光合衰退在时间上晚于倒2叶。旗叶对籽粒的贡献率为18.8%,倒2叶、倒3叶和倒4叶分别为14.2%、5.3%和-1.2%。研究认为,叶绿素含量的衰减程度直接影响了小麦叶片光合非气孔限制出现的时间,而与其变化的趋势和数值的大小没有直接关系。小麦下位提前衰老的叶片消耗大于积累,因此对籽粒的充实表现为负效应。The net photosynthetic rate(Pn), transpiration rate(Tr), stomatal (conductance)(Gs), (intercellular) CO_2 (concentration), chlorophyll (content) and the (contribution) rate of different (positions) leaf to grain of winter wheat were measured at grain filling stage while relay (intercropped) with cotton, under the (identical) fertility and soil moisture (condition). The (results) showed that the change trend of Pn and Tr were (consistent), and the order was flag leaf (FL), the second leaf (Cd2L), the third leaf (Cd3L) and the fourth (Cd4L) leaf from big to small. Along with the (senescence) (progress) of wheat leaves, the (chlorophyll) (content) descended rapidly. The photosynthesis decline of Cd3L and Cd4L were mainly due to (non-stomatal) (limitation,) FL and Cd2L were mainly due to stomatal (limitation) at prophase, but due to (non-stomatal) (limitation) at anaphase, and the time of (non-stomatal) (limitation) of FL was later (appeared) than that of Cd2L. The (contribution) rate of FL to grain was 18.8%, and that of Cd2L, Cd3L, Cd4L was 14.2%, (5.6%) and (-1.2%), (respectively). The (results) suggested that the attenuation level of (chlorophyll) (content) (directly) influence the time of (non-stomatal) (limitation) rather than the trend and (values). The (consuming) of earlier (senescent) leaves at lower (positions) is more than accumulation, therefore the (contribution) rate to the grain filling is in a negative (effect).

关 键 词：麦棉套作 冬小麦 光合衰退 

分 类 号：S512.1[农业科学—作物学] S311