Raza Muhammad Ali, Yasin Hassan Shehryar, Gul Hina, Qin Ruijun, Mohi Ud Din Atta, Khalid Muhammad Hayder Bin, Hussain Sajad, Gitari Harun, Saeed Amjed, Wang Jun, Rezaei-Chiyaneh Esmaeil, Sabagh Ayman El, Manzoor Amir, Fatima Akash, Ahmad Shakeel, Yang Feng, Skalicky Milan, Yang Wenyu
National Research Center of Intercropping, The Islamia University of Bahawalpur, Bahawalpur, Pakistan.
College of Agronomy, Sichuan Agricultural University, Chengdu, China.
Front Plant Sci. 2022 Nov 1;13:1006720. doi: 10.3389/fpls.2022.1006720. eCollection 2022.
Sustainable increases in crop production require efficient use of resources, and intercropping can improve water use efficiency and land productivity at reduced inputs. Thus, in a three-year field experiment, the performance of maize/soybean strip intercropping system differing with maize plant density (6 maize plants m-2, low, D1; 8 maize plants m-2, medium, D2; and 10 maize plants m-2, high, D3) was evaluated in comparison with sole maize or soybean cropping system. Results revealed that among all intercropping treatments, D2 had a significantly higher total leaf area index (maize LAI + soybean LAI; 8.2), total dry matter production (maize dry matter + soybean dry matter; 361.5 g plant-1), and total grain yield (maize grain yield + soybean grain yield; 10122.5 kg ha-1) than D1 and D3, and also higher than sole maize (4.8, 338.7 g plant-1, and 9553.7 kg ha-1) and sole soybean (4.6, 64.8 g plant-1, and 1559.5 kg ha-1). The intercropped maize was more efficient in utilizing the radiation and water, with a radiation use efficiency of 3.5, 5.2, and 4.3 g MJ-1 and water use efficiency of 14.3, 16.2, and 13.3 kg ha-1 mm-1, while that of intercropped soybean was 2.5, 2.1, and 1.8 g MJ-1 and 2.1, 1.9, and 1.5 kg ha-1 mm-1 in D1, D2, and D3, respectively. In intercropping, the land and water equivalent ratios ranged from 1.22 to 1.55, demonstrating that it is a sustainable strategy to improve land and water use efficiencies; this maximization is likely associated with the species complementarities for radiation, water, and land in time and space, which resulted in part from competition avoidance responses that maximize the economic profit (e. g., 1300 US $ ha-1 in D2) over sole maize (798 US $ ha-1) or sole soybean (703 US $ ha-1). Overall, these results indicate that optimizing strip intercropping systems can save 20-50% of water and land, especially under the present scenario of limited resources and climate change. However, further research is required to fully understand the resource capture mechanisms of intercrops in intercropping.
作物产量的可持续增长需要高效利用资源，而间作可以在减少投入的情况下提高水分利用效率和土地生产力。因此，在一项为期三年的田间试验中，评估了玉米/大豆带状间作系统在不同玉米种植密度（6株玉米/m²，低密度，D1；8株玉米/m²，中等密度，D2；10株玉米/m²，高密度，D3）下的表现，并与单作玉米或大豆种植系统进行了比较。结果表明，在所有间作处理中，D2的总叶面积指数（玉米叶面积指数+大豆叶面积指数；8.2）、总干物质产量（玉米干物质+大豆干物质；361.5 g/株）和总籽粒产量（玉米籽粒产量+大豆籽粒产量；10122.5 kg/ha）均显著高于D1和D3，也高于单作玉米（叶面积指数4.8、干物质产量338.7 g/株、籽粒产量9553.7 kg/ha）和单作大豆（叶面积指数4. 6、干物质产量64.8 g/株、籽粒产量1559.5 kg/ha）。间作玉米在辐射和水分利用方面更高效，辐射利用效率分别为3.5、5.2和4.3 g/MJ，水分利用效率分别为14.3、16.2和13.3 kg/ha·mm⁻¹，而间作大豆在D1、D2和D3中的辐射利用效率分别为2.5、2.1和1.8 g/MJ，水分利用效率分别为2.1、1.9和1.5 kg/ha·mm⁻¹。在间作中，土地当量比和水分当量比在1.22至1.55之间，表明这是提高土地和水分利用效率的可持续策略；这种最大化可能与物种在时间和空间上对辐射、水分和土地的互补性有关，部分原因是避免竞争的反应使经济利润最大化（例如，D2为1300美元/公顷），高于单作玉米（798美元/公顷）或单作大豆（703美元/公顷）。总体而言，这些结果表明，优化带状间作系统可以节省20%-50%的水和土地，特别是在当前资源有限和气候变化的情况下。然而，需要进一步研究以充分了解间作中作物的资源捕获机制。
