College of Agronomy, Sichuan Agricultural University, 211-Huimin Road, Wenjiang District, Chengdu, 611130, China.
Sichuan Engineering Research Center for Crop Strip Intercropping System, Key Laboratory of Crop Ecophysiology and Farming System in Southwest China (Ministry of Agriculture), Sichuan Agricultural University, Chengdu, China.
Photochem Photobiol Sci. 2020 Apr 15;19(4):462-472. doi: 10.1039/c9pp00369j.
Soybean (Glycine max L.) has been extensively cultivated in maize-soybean relay intercropping systems in southwest China. However, during the early co-growth period, soybean seedlings suffer from severe shading by maize resulting in lodging and significant yield reduction. The purpose of the present research was to investigate the reasons behind severe lodging and yield loss. Therefore, four different soybean genotypes (B3, B15, B23, and B24) having different agronomic characteristics were cultivated in intercropping and monocropping planting patterns. The results showed that under different planting patterns, the stem resistance varied among genotypes (P < 0.01). The lodging resistance index of B3, B15, B23, and B24 genotypes was 70.9%, 60.5%, 65.2%, and 57.4%, respectively, under intercropping, among which the B24 genotype was less affected by the shade environment as there was little decrease in the lodging resistance index of this genotype under intercropping. The lignin content of B23 and B24 was significantly higher than that of B3 and B15 under both planting patterns. Under intercropping, the hemicellulose content of B23 and B24 stems was significantly higher than that of B3 and B15. Compared to the monocropping, the content of mannose in the structural carbohydrate of soybean stems was decreased in all genotypes except B23, but the difference was not significant. The content of xylose in the structural carbohydrate of soybean stems was significantly higher than that in B3 and B15. Mannose content showed no significant difference among genotypes. The arabinose content of B24 was significantly higher than that of B3, B15, and B23. The effective pod number, seed number per plant, seed weight per plant and yield of soybean plants were significantly decreased under intercropping. Conclusively, manipulation of structural and nonstructural carbohydrate rich soybean genotypes in intercropping systems could alleviate the yield loss due to lodging.
在中国西南地区，大豆（Glycine max L.）已广泛种植于玉米-大豆间作套种系统中。然而，在早期共生阶段，大豆幼苗会受到玉米的严重遮荫，导致倒伏和显著减产。本研究的目的是探究严重倒伏和产量损失的原因。因此，选用具有不同农艺特性的四个不同大豆基因型（B3、B15、B23 和 B24）进行间作和单作种植模式下的种植。结果表明，在不同种植模式下，基因型间的茎阻力存在差异（P＜0.01）。B3、B15、B23 和 B24 基因型在间作条件下的抗倒伏指数分别为 70.9%、60.5%、65.2%和 57.4%，其中 B24 基因型受遮荫环境的影响较小，因为在间作条件下，该基因型的抗倒伏指数下降幅度较小。在两种种植模式下，B23 和 B24 的木质素含量均明显高于 B3 和 B15。在间作条件下，B23 和 B24 茎的半纤维素含量明显高于 B3 和 B15。与单作相比，除 B23 外，所有基因型大豆茎结构性碳水化合物中的甘露糖含量均降低，但差异不显著。大豆茎结构性碳水化合物中的木糖含量明显高于 B3 和 B15。除 B23 外，所有基因型的阿拉伯糖含量均显著高于 B3、B15 和 B23。B24 的阿拉伯糖含量明显高于 B3、B15 和 B23。间作条件下，大豆植株的有效荚数、单株粒数、单株粒重和产量均显著降低。综上所述，在间作系统中，操纵结构性和非结构性碳水化合物丰富的大豆基因型，可以缓解因倒伏造成的产量损失。
