Efficacy of Coco Peat Mulch treated with wood vinegar on control woody Borreria (Hedyotis Verticillata (L.) Lam.) at the vegetative stage

In Malaysia, The National Agro-Food Policy (NAFP 2011-2020) has brought focus on improving the farmer's income through the implementation of precision weed control methods to reduce uncertainties that related to managing variabilities in farm. Recently, mulching and herbicide application is a promising approach to reduce weed infestation, however there is limited literature on combined effect of mulching with natural plant products. Therefore, a study was carried out to determine the effect of different application rates of coco peat mulch treated with wood vinegar on the emergence and growth performance of woody borreria weed (Hedyotis verticillata (L.) Lam.) at the vegetative stage. The woody borreria was treated with different application rate of coco peat mulch at 4 t ha -1, 8 t ha -l and 12 t ha -l; and wood vinegar at 10%, 20% and 30%. The weed emergence, root length and shoot fresh weight of tested weed species were measured and data obtained was expressed as percentage of control (% of control). The weed emergence was completely inhibited by 100% when the bioassay species were treated at 8 t hal coco peat mulch + 30% wood vinegar (T6). At this application rate, a similar trend of inhibition was also observed for shoot fresh weight and root length. There was significant reduction on the shoot fresh weight of H. verticillata starting from 4 t ha-1 - 12 t hal coco peat mulch with the wood vinegar concentration ranging from 10% -30% (T3, T4, T6, T7, T8, and T9). At these application rates, the shoot fresh weight of the bioassay species was strongly inhibited by 82-100% (p<0.05). Though no significance difference were detected at the lower application of coco peat mulch at 4 t hal (T1, T2 and T3) as compared to the control, these application rates show strong root reduction with the value ranging from 62%-92% inhibition. These results suggest that the integration of wood vinegar with mulching according to the specific rates had provide optimum control of H. verticillata, thus highlighting its potential as a promising weed control method in relation to precise weed management.