Diversidad de especies de plantas arvenses en tres monocultivos del Bajío, México

R ESUMEN : Las plantas arvenses son fuertes competidoras en los cultivos, pero también constituyen un componente importante de los agroecosistemas, por lo que es relevante conocer aspectos de su ecología. El objetivo fue comparar la abundancia, riqueza y diversidad de arvenses presentes en monocultivos de maíz (mz), trigo (tg) y sorgo (sg). De noviembre 2018 a mayo 2019 se visitó el campo tres veces por mes, el muestreo se realizó por cuadrantes de 2 m 2 . Las plantas se identificaron a nivel de especie y se organizaron por su estatus migratorio. Se realizaron índices de diversidad, curvas de acumulación de especies, un Análisis de Kruskal Wallis y un Análisis Discriminante para comparar poblaciones de arvenses. m 2 . All plants were identified at the species level and organized by their immigration status. Diversity index, accumulation curves were calculated, also a Kruskal Wallis test and Discriminant analysis were made to compare between weeds populations. 28 species were found, the total richness was obtained for mz and tg but it did not for sg. The corn was the cropping with more species (S= 26) and, a significantly high diversity (H= 2.94), it also was observed in native and exotic weed (H = 1.91 y H = 1.94, respectively). The weed abundance was significantly high in mz. The composition of weed populations was different between crops, the AD with 83% of variance explained separated three groups according to the type of crop, which was reflected in the structure of the weed populations. Plant communities are different between crops despite being in a spatially homogeneous environment. Hence, factors associated with the crops are influencing the diversity patterns observed. Species richness is inside of range of other agroecosystems but, diversity is higher than some studies reported for traditional and intensive farming systems. The present of native species in local diversity is a positive ecological indicator for crops.