Diversity enhances agricultural productivity via rhizosphere phosphorus facilitation on phosphorus-deficient soils
Diversity enhances agricultural productivity via rhizosphere phosphorus facilitation on phosphorus-deficient soils
复制标题
多样性通过缺磷土壤的根际磷促进作用提高农业生产力
DOI：
10.1073/pnas.0704591104
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发表时间：
2007-07-03
影响因子：
11.1
通讯作者：
Zhang, Fu-Suo
中科院分区：
文献类型：
--
作者：
Li, Long;Li, Shu-Min;Zhang, Fu-Suo
间作，即在同一块土地上同时种植至少两种作物，可以大大提高粮食产量。豆科牧草间作由于豆科固氮作用而被认为是高产的。然而，许多农业土壤缺乏磷。在这里，我们表明，一种新的机制，其中一种作物品种的磷动员增加了第二种作物品种的生长交替行，导致产量大幅增加缺磷土壤。通过4年田间试验，研究了玉米（Zea mays L.）在低磷高氮土壤上间作蚕豆（Vicia faba Q）增产26%。在另一个田间试验中，我们发现玉米的丰产是由于蚕豆和玉米之间的地下相互作用。在较低的磷肥施用量（112.5 kg O_2O_5/hm 2）下，与小麦间作相比，蚕豆间作显著提高了玉米籽粒产量，地上生物量略有提高。通过使用渗透性和非渗透性根屏障，我们发现，玉米的超高产是由于其吸收磷动员的根际酸化通过蚕豆根释放的有机酸和质子。蚕豆与玉米的生长季节和生根深度不同，导致其超产。在低磷土壤上间作的产量大幅度增加可能对严重风化的土壤特别重要。
Intercropping, which grows at least two crop species on the same pieces of land at the same time, can increase grain yields greatly. Legume-grass intercrops are known to overyield because of legume nitrogen fixation. However, many agricultural soils are deficient in phosphorus. Here we show that a new mechanism of overyielding, in which phosphorus mobilized by one crop species increases the growth of a second crop species grown in alternate rows, led to large yield increases on phosphorus-deficient soils. In 4 years of field experiments, maize (Zea mays L.) overyielded by 43% and faba bean (Vicia faba Q overyielded by 26% when intercropped on a low-phosphorus but high-nitrogen soil. We found that overyielding of maize was attributable to belowground interactions between faba bean and maize in another field experiment. Intercropping with faba bean improved maize grain yield significantly and above-ground biomass marginally significantly, compared with maize grown with wheat, at lower rates of P fertilizer application (112.5 kg Of P2O5 per hectare). By using permeable and impermeable root barriers, we found that maize overyielding resulted from its uptake of phosphorus mobilized by the acidification of the rhizosphere via faba bean root release of organic acids and protons. Faba bean overyielded because its growth season and rooting depth differed from maize. The large increase in yields from intercropping on low-phosphorus soils is likely to be especially important on heavily weathered soils.