摘要
研究玉米-大豆带状套作下大豆不同生育时期的叶片形态和光合特性,探讨叶片对带状套作的响应机制,为耐荫大豆品种筛选与选育提供依据。以南豆12、桂夏1号和华夏5号等3个耐荫性存在显著差异的大豆品种为试验材料,在大田试验条件下,活体测定植株叶倾角、叶柄长度、叶形指数和光合特性,取样测定大豆叶片的比叶重和单株叶面积。结果表明:与单作相比,玉米大豆带状套作条件下,大豆叶倾角显著增加,苗期和花期上层增幅大,荚期则为下层增幅最大;叶形指数在苗期和花期显著增加,不同生育时期各品种不同层位对套作环境的响应程度不同;叶柄长度从大到小均依次表现为上层、中层、下层,且在套作下显著增加,其中苗期和花期上层增幅最大;比叶重和单株叶面积减小,大豆胞间CO2浓度上升,叶片净光合速率、气孔导度和蒸腾速率均显著下降。不同品种对带状套作的响应程度不同,强耐荫品种南豆12叶倾角增幅大而叶柄长度增幅最小,比叶重、单株叶面积和净光合速率下降幅度均为最小;荫蔽敏感型品种华夏5号叶柄长度增幅最大而叶倾角增幅最小,叶片胞间CO2浓度显著增加,净光合速率和单株叶面积下降均最为明显。强耐荫品种南豆12在玉米大豆带状套作模式下,能够通过调节自身叶片形态适应环境变化,光合速率下降幅度较小,从光能截获和利用方面均表现出了对套作较强的适应能力。
Leaf morphological characteristics and photosynthetic traits were studied to investigate the leaf response to changed environment in relay strip intercropping system. Three varieties with different shade- tolerance,ND12,GX1 and HX5 were used in the field experiment to investigate leaf angle,petiole length,leaf index,photosynthetic characteristics in vivo and specific leaf weight,leaf area per plant. Compared with monoculture,the results showed that leaf angle increased significantly in relay strip intercropping system,and the maximum increase was in upper layer at seedling and flowering stage,in lower layer at podding stage. Leaf index also increased significantly at seedling and flowering stage,and the response degree of soybean leaf layers were different at different stages. As with the leaf index,leaf petiole length of seedling and flowering stage increased significantly,and petiole length rendered as upper middle lower. Photosynthetic rate（ Pn）,stomatal conductance（ Gs）,transpiration rate（ Tr）,specific leaf weight（ SLW） and leaf area per plant（ LAP） all decreased significantly,but Ci increased. Among these 3 varieties,ND12 had the least increase in leaf angle,but the most increase in petiole len-gth and the most decrease in SLW,LAP and photosynthetic rate. HX5 had the most increase in petiole length and the least increase in leaf angle,and the decrease of photosynthetic rate and LAP is the most. ND12,shade- tolerant variety,adjusted leaf morphology and position to increase light capture and light utilization. Accordingly,ND12 adapted well relay strip intercropping system.
出处
《中国油料作物学报》
CAS
CSCD
北大核心
2016年第4期452-459,共8页
Chinese Journal of Oil Crop Sciences
基金
四川省南充市应用技术研究与开发资金项目(15A0062)
国家大豆现代产业技术体系建设专项(CARS-04-PS19)
关键词
大豆
带状套作
叶片形态
光合特性
叶倾角
叶柄长度
Soybean
Relay strip intercropping
Leaf morphology
Photosynthetic characteristic
Leaf angle
Leaf petiole length
