黄淮海棉区棉麦两熟光能流与物质流研究Ⅰ．共生期棉行光分布与日总量

Studies on Flows of Materials,Light and Energy in Wheat─CottonDouble Cropping Fields in Huanghuaihai Cotton AreaⅠ.Light Distribution and Total Solar Radiation Received by Re-served Row for Cotton During Co─growing Period with Wheat

１９９２～１９９４年针对黄淮海棉区棉麦两熟套种棉花迟发晚熟进行不同配置方式的田间试验研究。结果表明，不同配置方式棉行光分布型不同，宽窄行配置方式棉行光分布呈宽的“凸”字型，等行配置方式棉行光分布呈偏而窄的“凸”字型。共生期间棉茬小麦正处在生长发育旺盛期，丰产小麦株高从５５ｃｍ增加到８５ｃｍ，旗叶和旗下２叶披出宽度达到２０ｃｍ，单位面积株数、单株叶面积和叶面积系数均达到最大并随后逐渐消减，４种配置方式全共生期棉行日总受光量仅为４６．６％±１３．２％，棉花受光量仅为５３．９％±７．６％，光合有效辐射预留棉行为４０８．２８±１１５．５３μｍｏｌｍ－２ｄ－１，棉花为４７３．５９±６６．８５μｍｏｌｍ－２ｄ－１，分别比一熟棉田减弱５３．４％±１３．２％和４６．１％±７．６％。这些结果说明，套种棉花共生期光热资源严重不足是客观存在的，但处理间存在明显的差异。棉茬小麦选择东西行向，推广垄作和选用矮秆小麦品种，采用标准３─２式或４─２式配置方式有利于共生期预留棉行获得较多的光热资源，促进棉花早发。

The field experiments during 1992～1994 were aimed at the retarding develop-ing and maturation of delayed cropping cotton in Huanghuaihai cotton Area.The resultsindicated that the pattern of light distribution in cotton rows were different under differentcropping patterns.The pattern of light distribution in skip rows was like a wide 凸,whilein uniform row space like a narrow 凸.During the wheat-Cotton co-growing period,thewheat grew vigrously,the height of high-yield wheat was 55cm to 85cm,the width ofshade caused by draped parts of flag and second leaf was 20cm.The plant number,leafarea per plant and leaf area index first got the heighest and then dropped gradually.Theaverage percentage of solar radiation received by cotton row of four relayed cropping pat-terns was only 46.6%±13.2%,while that received by cotton was only 53.9%±7.6%.The photosyntheticallv active radiation(PAR) in reserved row for cotton was 408.28±115.53μmolm-2d-1, while PAR received by cotton was only 473.59± 66.85μmolm-2d-1,which decreased by 53.4%±13.2%and 46.1%±7.6% than single cropping field,respec-tively.The results showed that the resources of light and heat for relay cropping cottonwere inadequate heavily but there were great different among treatments.It’s beneficial tocotton growth to select east-west row direction,ridge culture for cotton,lower wheatvarieties,standard relay cropping patterns of three rows for wheat and two for cotton(3─2 pattern)and 4─2 pattern,with which the cotton row will obtain more light and heatduring the co-growing period and thus promote cotton developing early.