Abstract: In order to investigate the impacts of intercropping sorghum (Sorghum bicolor) with soybeans (Glycine max) on photosynthetic characteristics and changes of productivity in saline-alkali soil, this study used sorghum monoculture (TS) and soybean monoculture (DS) as controls. Four intercropping patterns were established:sorghum-soybean at a ratio of 1:1 (T1D1), 1:3 (T1D3), 2:2 (T2D2), and 2:4 (T2D4). The research focused on studying the production performance, photosynthetic characteristics, and nutritional value of sorghum. The results indicated that intercropping positively influenced the growth of sorghum, while showed no significant difference in soybeans. Under different intercropping ratios, the land equivalent ratios were all greater than 1, with the highest ratio of 1.22 in T1D3. The optimal performance for sorghum photosynthetic parameters (Pn, Ci, Gs, Tr) was observed in T2D4, while for soybeans, T1D3 exhibited the best photosynthetic characteristics. Additionally, T2D4 demonstrated higher crude protein content, reaching 10.03%. Principal component analysis (PCA) found that T2D4 was the most favorable intercropping ratio, creating a conducive microenvironment within the canopy, and resulting in higher and superior yields for both sorghum and soybeans.

Key words: Saline-alkali land, Intercropping, Yield, Photosynthetic characteristics

摘要： 为研究盐碱地甜高粱（Sorghum bicolor）间作大豆（Glycine max）行比对光合特性变化生产性能的影响，确定科学合理的间作行比，本研究以甜高粱单作（TS），大豆单作（DS）为对照，设置甜高粱-大豆间作1：1（T1D1），1：3（T1D3），2：2（T2D2）和2：4（T2D4）4种间作模式，对两种作物生产性能、光合特性及甜高粱营养价值进行研究。结果表明，间作促进甜高粱的生长，但对大豆无明显差异。间作行比下，土地当量比均大于1，其中T1D3土地当量比最大，达1.22；甜高粱Pn，Ci，Gs，Tr表现最好的是T2D4，大豆光合特性表现最好的是T1D3处理；同时，T2D4处理甜高粱也拥有较高的粗蛋白含量，为10.03%。经主成分（PCA）分析得出T2D4最好，该间作行比有利于创造良好的群体冠层内部光环境，从而收获较高较优的甜高粱草产量和大豆产量。

关键词: 盐碱地, 间作, 产量, 光合特性