Stale Seedbed and Narrow Row Spacing Combinations to Suppress Weeds in Kenaf (Hibiscus cannabinus L.)

In contrast to other agronomic practices, weed management remains an unexplored area of research in kenaf ( Hibiscus cannabinus L.). The objective of this study was to investigate stale seedbed and row spacing manipulations for weed suppression in kenaf. A field trial was conducted from 2022 to 2023 in Greece in a randomised complete block design (RCBD) that was established according to the split‐plot arrangement. Two kenaf row spacings formed the main plots: 60‐ and 30‐cm. Three stale seedbed (SSB) manipulations formed the subplots: SSB‐0, SSB‐1, and SSB‐2. In subplots SSB‐0, weeds were left uncontrolled. In subplots SSB‐1 and SSB‐2, weeds were controlled with glyphosate (2700 g a.e. ha −1 ) 3 and 6 weeks after seedbed preparation, respectively. Stale seedbed affected weed NDVI and kenaf biological cycle ( p ≤ 0.001). The most weed‐suppressive combination of row spacing and stale seedbed was 30 cm/SSB‐2. 60cm/SSB‐2 and 30‐cm/SSB‐1 reduced weed infestation compared to 60‐cm/SSB‐1, 60‐cm/SSB‐0, and 30‐cm/SSB‐0. Kenaf establishment rate was over 75% for the 30‐cm/SSB‐2, 30‐cm/SSB‐1, 60‐cm/SSB‐2, and 60‐cm/SSB‐1 interactions, while the lowest value (42%) was recorded for 60‐cm/SSB‐0. The most productive interactions were 30‐cm/SSB‐1 and 30‐cm/SSB‐2 that yielded more than 18.4 t ha −1 of stem dry biomass. Further research is required to evaluate stale seedbed and other agronomic practices for weed suppression in kenaf and other promising industrial crops under different soil‐climatic conditions.