Evaluation of mulching, stale seedbed, hand weeding and hoeing for weed control in organic garden pea (Pisum sativum sub sp. Hortens L.)

Abstract

Weeds are often recognized as the principal biotic constraint to organic crop production. Development of suitable weed control measures is, therefore, a prerequisite for profitable organic farming. A field experiment was conducted during the winter season of 2003–2004 and 2004–2005 in the Indian Himalayas to evaluate the effect of mulching, stale seedbed, hand weeding and hoeing on weeds and yield of organic garden pea (Pisum sativum sub sp. Hortens L.). The weed population ranged from 249–477 m⁻², and Polygonum plebejum L. (34%), Melilotus indica L. (31%) and Avena ludoviciana Dur. (17%) were the predominant weeds in the experimental field. Season long weed-crop competition reduced the green pod yield of garden pea by 74% in 2003–2004 and 93% in 2004–2005. All the weed control treatments significantly reduced the population and biomass of weeds resulting in significant increase in green pod yield of garden pea compared to unweeded control. The highest weed control efficiency (84% reduction in weed biomass) was achieved with hand weeding 30 and 60 days after sowing (DAS) closely followed by stale seedbed coupled with one hand weeding (77%). Both these treatments produced significantly higher green pod yield compared to other treatments in both the years. In 2003–2004, hand weeding (30 and 60 DAS) recorded the highest gross margin (Indian Rupees 115,400 ha⁻¹) closely followed by stale seedbed coupled with one hand weeding (Indian Rupees 109,700 ha⁻¹). In the second year, however, the latter treatment gave the highest gross margin (Indian Rupees 56,900 ha⁻¹) compared to other treatments.

Keywords:

• garden pea
• hand weeding
• mulch
• organic farming
• stale seedbed
• weed control