Some factors affecting the field establishment of sub-tropical pasture legumes in Rhodesia.

Abstract

The establishment of Stylosanthes guyanensis cv. Oxley (fine-stem stylo) into reverted sandveld grassland and of Oxley stylo, Macroptilium atropurpureum cv. Sinatra, Desmodium intortum, and D. uncinatum cv. Silverleaf in arable land, was studied in a series of field trials at Marandellas, Rhodesia.More efficient establishment was achieved when the seed was drilled at a depth of 1 cm rather than broadcast on the soil surface. Burning immediately before discing, thorough discing, and rolling before and after drilling also improved the establishment of stylo in grassland. Heavy grazing during the winter following establishment, did not reduce the survival of stylo plants.On arable land soil sterilization with methyl bromide increased emergence and winter survival of seedlings. Mulching, too, improved establishment. A range of pasture legumes was established satisfactorily under a maize crop. Where weeds were effectively controlled, seeding immediately after maize sowing was most efficient, but otherwise it appeared desirable to eliminate the early flush of weeds and to undersow the legumes about six weeks after the maize was sown.

Keywords: botany; desmodium intortum; desmodium uncinatum; establishment; field trial; grassland; legumes; macroptilium atropurpureum; pasture legumes; rhodesia; sandveld; seeding; stylosanthes guyanensis; treatments; zimbabwe