Li Chunjie, Dong Yan, Li Haigang, Shen Jianbo, Zhang Fusuo
Center for Resources, Environment and Food Security (CREFS), China Agricultural University, Beijing, 100193, China.
College of Resources and Environment, Yunnan Agricultural University, Kunming, 650201, China.
Sci Rep. 2016 Jan 5;6:18663. doi: 10.1038/srep18663.
Rhizosphere processes stimulate overyielding and facilitative phosphorus (P) uptake in cereal/legume intercropping systems. However, little is known about when and how rhizosphere alteration of legumes plays a role in improving P uptake by cereals. Wheat was grown isolated, monocropped or intercropped with faba bean in pots with low-P soil. The biomass, P content, carboxylates and phosphatases activity were measured in 15 destructive samplings. Intraspecific competition of the biomass and P uptake of monocropped wheat was not significant before 40 and 36 days after sowing (DAS), whereas there was interspecific competition of biomass of intercropped wheat before 66 DAS. However, afterwards, the increments of the biomass and P uptake of the intercropped wheat were 1.3-1.9 and 1.9-2.3 times of increment of monocropped wheat. Meanwhile, the concentrations of malate and citrate and the acid phosphatase activity in the rhizospheres of intercropped wheat were significantly increased, which suggested that wheat/faba bean intercropping is efficient in P utilization due to complementary P uptake in the early growth stage and the positive interactions of the rhizosphere processes when the soil P was depleted.
根际过程促进了谷物/豆类间作系统中的超产和促进性磷（P）吸收。然而，关于豆类根际变化何时以及如何在提高谷物对磷的吸收中发挥作用，人们知之甚少。将小麦单独种植、单作或与蚕豆在低磷土壤的花盆中进行间作。在15次破坏性采样中测量了生物量、磷含量、羧酸盐和磷酸酶活性。单作小麦生物量和磷吸收的种内竞争在播种后40天和36天之前不显著，而间作小麦生物量的种间竞争在播种后66天之前存在。然而，在此之后，间作小麦生物量和磷吸收的增量分别是单作小麦增量的1.3 - 1.9倍和1.9 - 2.3倍。同时，间作小麦根际中苹果酸和柠檬酸的浓度以及酸性磷酸酶活性显著增加，这表明小麦/蚕豆间作在早期生长阶段由于磷吸收的互补性以及土壤磷耗尽时根际过程的积极相互作用而在磷利用方面效率较高。
