Liu Xin, Rahman Tanzeelur, Yang Feng, Song Chun, Yong Taiwen, Liu Jiang, Zhang Cuiying, Yang Wenyu
College of Agronomy, Sichuan Agricultural University, Chengdu, China.
Key Laboratory of Crop Ecophysiology and Farming System in the Southwest, Ministry of Agriculture, Chengdu, China.
PLoS One. 2017 Jan 5;12(1):e0169218. doi: 10.1371/journal.pone.0169218. eCollection 2017.
The crop intercepted photosynthetically active radiation (PAR) and radiation use efficiency (RUE) vary markedly in different intercropping systems. The HHLA (horizontally homogeneous leaf area) and ERCRT (extended row crop radiation transmission) models have been established to calculate the intercepted PAR for intercrops. However, there is still a lack of study on the intercepted PAR and RUE under different intercropping configurations using different models. To evaluate the intercepted PAR and RUE in maize and soybean under different intercropping systems, we tested different strip intercropping configurations (SI1, SI2, and SI3 based on ERCRT model) and a row intercropping configurations (RI based on HHLA model) in comparison to monoculture. Our results showed that the intercepted PAR and RUE of intercropping systems were all higher than those of monoculture. The soybean intercepted PAR in strip intercropping was 1.35 times greater than that in row intercropping. In row intercropping (RI), the lack of soybean intercepted PAR resulted in a significant reduction of soybean dry matter. Therefore, it is not the recommended configuration for soybean. In strip intercropping patterns, with the distance between maize strip increased by 0.2 m, the intercepted PAR of soybean increased by 20%. The SI2 (maize row spacing at 0.4 m and the distance between maize strip at 1.6 m) was the recommended configuration to achieve the highest value of intercepted PAR and RUE among tested strip intercropping configurations. The method of dry matter estimation using intercepted PAR and RUE is useful in simulated experiments. The simulated value was verified in comparison with experimental data, which confirmed the credibility of the simulation model. Moreover, it also provides help in the development of functional-structural plant model (FSPM).
在不同的间作系统中，作物截获的光合有效辐射（PAR）和辐射利用效率（RUE）差异显著。已建立HHLA（水平均匀叶面积）和ERCRT（扩展行作物辐射传输）模型来计算间作作物截获的PAR。然而，对于使用不同模型的不同间作配置下截获的PAR和RUE仍缺乏研究。为了评估不同间作系统下玉米和大豆截获的PAR和RUE，我们测试了不同的条带间作配置（基于ERCRT模型的SI1、SI2和SI3）和一种行间作配置（基于HHLA模型的RI），并与单作进行比较。我们的结果表明，间作系统截获的PAR和RUE均高于单作。条带间作中大豆截获的PAR比行间作高1.35倍。在行间作（RI）中，大豆截获PAR的缺乏导致大豆干物质显著减少。因此，它不是大豆推荐的配置。在条带间作模式中，随着玉米条带间距增加0.2 m，大豆截获的PAR增加20%。在测试的条带间作配置中，SI2（玉米行距0.4 m，玉米条带间距1.6 m）是实现截获PAR和RUE最高值的推荐配置。利用截获的PAR和RUE估算干物质的方法在模拟实验中很有用。将模拟值与实验数据进行比较验证，证实了模拟模型的可信度。此外，它还为功能-结构植物模型（FSPM）的开发提供了帮助。
