Weed species diversity: cropping sequences influence under mid hill conditions of Himachal Pradesh

Abstract

An appraisal of weed species association was undertaken in a continuing experiment during kharif- 2021 and rabi- 2022 at Bhadiarkhar farm of CSKHPKV, Palampur in order to study the impact of various cropping sequences on weed diversity. Ten cropping sequence viz., C -maize–wheat, C -maize–gobhi sarson + toria, 1 2 C -dhaincha–early cabbage–french bean, C -sunhemp–vegetable pea–frenchbean, C -maize + 3 4 5 soybean–chickpea + linseed, C -rice–wheat+gram, C -hybrid sorghum + hybrid bajra–oats + sarson, C - 6 7 8 Hybrid sorghum + hybrid bajra–ryegrass + berseem, C -baby corn–broccoli–French bean,C -okra- 9 10 turnip–tomato were tested. In each season thirteen weed species were found predominant in the experimental field. Weed density data were collected at monthly interval and seasonal weed diversity indices were worked out. The difference in the number of species between treatments was not large. Diversity indices were highest in the low disturbance sequences, particularly those with intercropping systems. Weed species assembly showed little discrimination across treatments confirming the ability of seed banks to buffer disturbances across a variety of cropping systems. The use of diversity indices revealed part of the complexity of weed communities associated with disturbance in cropping systems which may be more meaningful to weed management.