Seedbed requirements for Dolichos lablab

Abstract

Several methods of seedbed preparation were compared for sowing Dolichos Lablab into paspalum dominant pastures on the North Coast of New South Wales. Competition from grass reduced the growth of dolichos seedlings. Dolichos yields were highest when cultivation reduced grass growth by at least 70 per cent, or when the seedbed was sprayed with 10 kg acid equivalent 2,2-DPA per hectare. The results suggested that lack of effective nodulation when seed was inoculated with Rhizobium strain CB 454 or NA 106 was a prime factor in the low competitive ability of dolichos seedlings. It is concluded that cultivation is the better method of reducing grass competition because it also causes mineralization of soil nitrogen. This ensures an adequate nitrogen supply even if inoculation fails.