ABSTRACT

In traditional polycultures such as milpas, soil degradation and the loss of agrodiversity, threaten rural food security. Although agroecological management using crop functional and genetic diversity could improve soil fertility and family nutrition, experimental evidence is scarce. We conducted a field experiment in which conventional agricultural management (CON) was compared to an agroecological alternative (AGR), with interspecific and intraspecific diversification factors. We hypothesized that: (1) the higher input of organic matter and the suspension of tillage in AGR plots would improve soil conditions, nutrient content and productivity in maize, and intra-root colonization by mycorrhizal fungi as compared to CON plots; and that (2) these conditions would further improve in AGR management with increased intra- and interspecific diversity, since a diverse plant community in the rhizosphere should enhance microbial activity. AGR increased pH, the soil availability of K, Ca and Mg, K in leaves, and mycorrhizal colonization. Within AGR, diversified treatments temporarily increased NO₃⁻ in the soil. The fixation of nitrogen by additional legumes could have produced this result. We conclude that AGR with interspecific diversification is a viable alternative to CON, since a variety of additional edible plants became available concomitantly with the improvement of mycorrhizal relationships and soil conditions.

摘要

在传统的多元文化中，例如milpas、土壤退化和农业多样性的丧失，威胁着农村粮食安全。虽然利用作物功能和遗传多样性进行农业生态管理可以提高土壤肥力和家庭营养，但实验证据很少。我们进行了一项田间试验，其中将传统农业管理 (CON) 与农业生态替代方案 (AGR) 进行了比较，具有种间和种内多样化因素。我们假设：（1）与 CON 地块相比，AGR 地块中较高的有机质投入和暂停耕作将改善玉米的土壤条件、养分含量和生产力，以及菌根真菌在根内的定殖；(2) 随着种内和种间多样性的增加，这些条件将进一步改善 AGR 管理，因为根际中多样化的植物群落应该会增强微生物的活性。AGR 增加了 pH 值、K、Ca 和 Mg 的土壤有效性、叶片中的 K 和菌根定植。在 AGR 中，多样化的处理暂时增加了 NO₃ ^-在土壤中。额外的豆类对氮的固定可能会产生这种结果。我们得出结论，具有种间多样化的 AGR 是 CON 的可行替代方案，因为随着菌根关系和土壤条件的改善，各种额外的可食用植物变得可用。