马铃薯/玉米套作对玉米光合特性和产量的影响  

Variations in photosynthetic characteristics and yield of maize in potato/maize intercropping systems

作　　者：黄承建[1,2] 赵思毅[2] 王季春[1] 王龙昌[1] 赵勇[1] 廖采琴[1] 魏鑫[1] 郝艳睿[1] 蔡叶茂[1] 

机构地区：[1]西南大学农学与生物科技学院南方山地农业教育部工程研究中心,重庆400716 [2]四川省达州市农业科学研究所,达州635000

出　　处：《中国生态农业学报》2013年第5期552-560,共9页Chinese Journal of Eco-Agriculture

基　　金：国家重点基础研究发展计划(973计划)项目(2011CB100402)资助

摘　　要：以单作玉米为对照,设置2︰2和3︰2两种马铃薯/玉米套作行数比,研究大田套作条件下玉米光合特性的动态变化及对产量的影响。结果表明:套作显著降低了玉米整个生育期叶面积指数(LAI);比叶重(SLW)生育前期显著降低,乳熟期与单作差异不显著;Chla、Chlb、Chla+Chlb套作3︰2行数比整个生育期显著低于单作,套作2︰2行数比生育前期显著低于单作,乳熟期差异不显著。2种行数比叶绿素a/b值拔节期套作低于单作,吐丝期高于单作。与套作2︰2行数比相比,套作3︰2行数比LAI苗期差异不显著,生育后期显著低于套作2︰2行数比;Chla、Chlb、Chla+Chlb生育前期显著高于2︰2行数比,乳熟期差异不显著;叶绿素a/b值吐丝期和乳熟期显著低于套作2︰2行数比,生育前期差异不显著;SLW整个生育期差异不显著。2种行数比玉米套作和单作PAR、Pn、Gs、Tr、WUE均随叶位的降低而降低。套作降低了玉米下位叶的Pn、Gs、Tr,提高了下位叶的Ci,上位叶Pn、Gs、Tr、Ci套作和单作差异不显著。上、下叶位的PAR套作均显著高于单作,上、下叶位的WUE套作与单作差异均不显著。套作3︰2行数比上、下叶位PAR、Gs、Tr均显著低于2︰2行数比;2种行数比上位叶Pn相近,下位叶Pn套作3︰2行数比显著低于2︰2行数比。下位叶Pn的降低套作3︰2行数比受气孔因素限制,套作2︰2行数比受非气孔因素限制。总之,马铃薯/玉米套作改变了玉米的光合特性,并显著降低了玉米的籽粒产量。套作2︰2行数比和套作3︰2行数比土地当量比分别为0.88、1.24,前者无套作优势,在生产中不宜采用,后者具有较强的套作优势,宜在生产中推广。Intercropping of potato with maize has been a traditional cropping system widely practiced in the mountain regions of Southwest China.Although changes have occurred in light environment of maize due to intercropping,few reports have been analyzed the importance of competition for light and related effects on maize yield in potato/maize associations.A potato/maize intercropping field experiment with two different potato-maize row ratios was carried out to determine the dynamic changes in maize features.The features analyzed included leaf area index（LAI）,special leaf weight（SLW）,chlorophyll a（Chla）,chlorophyll b（Chlb）,total chlorophyll（Chla＋Chlb） and chlorophyll a/b ratio（Chla/b） of maize at different growth stages.Also photosynthetic active radiation（PAR） and gas exchange parameters of upper and lower leaves at tasseling stage of mazie were analyzed along with yield using mono-cropped maize as the control.The respective potato-to-maize row number ratios used in the study were 2：2 and 3：2.The results showed a substantial drop in maize LAI at all growth stages while SLW only dropped at the early growth stages before milking under intercropping compared with monocropping.Chla,Chlb and Chla＋Chlb also markedly decreased in the 3：2 intercropping system at all growth stages while it only decreased in the 2：2 intercropping system at seedling,jointing and silking stages.Chla/b ratio dropped at jointing stage,was subsequently enhanced at silking stage and showed no significant difference at seedling and milk stages.Compared with the 2︰ 2 intercropping system,the 3：2 intercropping system had significantly lower LAI at all the growth stages except the seedling stage.Also noted were high Chla,Chlb and Chla＋Chlb at all the growth stages except the milking stage,and high Chla/b ratio at silking and milking stages.SLW was not significantly different at all growth stages between 2：2 and 3：2 intercropping systems.Furthermore,PAR,net photosynthesis rate（Pn）,stomatal conductance�

关 键 词：马铃薯 玉米套作 单作 行数比 光合特性 产量 土地当量比 

分 类 号：S344[农业科学—作物栽培与耕作技术]