Lang Jakob, Ramos Sergio E, Reichert Linus, Amboka Grace M, Apel Celina, Chidawanyika Frank, Detebo Andargachew, Librán-Embid Felipe, Meinhof David, Bigler Laurent, Schuman Meredith C
Department of Geography, University of Zurich, 8057 Zurich, Switzerland.
Department of Chemistry, University of Zurich, 8057 Zurich, Switzerland.
ACS Agric Sci Technol. 2024 Sep 24;4(10):1074-1082. doi: 10.1021/acsagscitech.4c00386. eCollection 2024 Oct 21.
Push-pull technology refers to a promising mixed cropping practice for sustainable agricultural intensification, which uses properties of intercrop and border crop species to defend a focal crop against pests. Currently, the most widely practiced system uses spp. as intercrop and Brachiaria or Napier grass as border crops to protect maize () against both insect pests and parasitic weeds. Several previous studies have demonstrated the efficacy of the push-pull system, but research on the underlying chemical mechanisms has mostly been limited to laboratory and glasshouse experiments that may not fully reproduce the complexity of the system under natural conditions. To address this limitation, we performed a large-scale study in farmer-operated push-pull maize fields in three east African countries. We compared maize leaf extracts from plants grown on push-pull fields with maize from fields employing conventional agricultural practices to assess the influence of push-pull cultivation on the maize metabolome. We identified two benzoxazinoid glycosides, which are known to have antiherbivore properties and were present in greater relative abundance in push-pull-cultivated maize leaves across three countries. Our data thus suggest that maize cultivated under push-pull has an increased resistance to herbivore attack compared to maize grown under conventional local agricultural practices.
推拉技术是一种用于可持续农业集约化的很有前景的混合作物种植方式，它利用间作作物和边际作物物种的特性来保护目标作物免受虫害。目前，应用最广泛的系统使用 spp. 作为间作作物，臂形草或象草作为边际作物，以保护玉米（ ）免受害虫和寄生杂草侵害。此前的多项研究已证明了推拉系统的功效，但对其潜在化学机制的研究大多局限于实验室和温室实验，而这些实验可能无法完全重现自然条件下该系统的复杂性。为解决这一局限性，我们在东非三个国家由农民经营的推拉玉米田中开展了一项大规模研究。我们将在推拉田中种植的玉米叶片提取物与采用传统农业做法的田地里的玉米进行比较，以评估推拉种植对玉米代谢组的影响。我们鉴定出了两种苯并恶嗪类糖苷，已知它们具有抗食草动物特性，并且在三个国家采用推拉种植的玉米叶片中相对丰度更高。因此，我们的数据表明，与采用传统当地农业做法种植的玉米相比，采用推拉技术种植的玉米对食草动物攻击的抵抗力增强。
