Weed Management in Dryland Paddy Farming for Environmental Conservation

Weeds become the major thread in the agriculture system especially for rice crops. Individual density per 0,1 m could decrease 57% of dryland rice production. We aimed to determine the strategy for manage the rice weeds in eco-friendly dryland as the effort to conserve the biodiversity. The methodology used is mixed method with observation and in-depth interview. The research was conducted in July - Oktober 2018, Sudimoro district, Pacitan Regency, East Java. The weeds that dominantly by important value index is Alternanthera sessilis (L.) R.Br. Ex DC (4,41) and Synedrella nodiflora (L.) J. Gaertner (2,84). The farmer tends to manage the weed chemically; even 100% respondent admitted the use of 42.86% chemical and mechanical to manage the weeds, meanwhile the rest 57.14% used only chemical (herbicide). To the farmers, the use of herbicide is believed as the most effective solution, it takes only few times, less energy, and more affordable than mechanic control. However, 42.86% of respondents indicated that the weed turned more resistant because even it was sprayed by herbicide, the weeds kept growing up. In the other side, the existence of pollinator insect and odonata were no longer as much as in the past time, moreover, somehow, odonata was totally disappeared. This reflection shows that the quality of ecosystem was disturbed by the use of herbicide. The management using the prior ecological principles is the best solution to conserve the ecosystem. This one can be gained through combining mechanical and biologycal management.