Agronomic studies on Pigeon pea (Cajanus cajan (L) Millsp.) II.* Responses to sowing density

Abstract

Vegetative and seed yield in Cajanus cajan accession UQ1 were investigated over nine sowing densities ranging from 6727 to 215,278 plants per hectare. Dry matter yield per plant declined asymptotically with increasing density, while the yield per hectare v. density relationship was described by a parabolic curve. The highest yield per hectare (22,950 kg) was produced at the 0.305 by 0.305 m spacing (107,639 plants ha-1). Maximum seed yield (2774 kg ha-1) was attained at a relatively low density at a spacing 0.914 by 0.610 m (17,940 plants ha-1). At higher densities, increased stand mortality and reduced numbers of pods per plant resulted in severe yield reductions. Reduced pod number per plant was related to significant reductions in the number of pod-producing branches and the inflorescence-bearing stem length, with little change in seed size or seeds per pod. Interactions of yield components, leaf area index, and other plant parameters are discussed. *Part I, Aust. J. Agric. Res., 26: 43 (1975).