Comparative growth, water use and yield of chickpea, safflower and wheat in south-eastern Queensland

Abstract

Growth, yield and water use of chickpea (Cicer arietinum), and safflower (Carthamus tinctorius), were compared with those of wheat (Triticum aestivum), to determine their merits as alternative crops. The experiment was conducted on a vertisol at Dalby in south-eastern Queensland in a season of below average rainfall. Each crop was grown at 4 plant population densities (PPD), namely 14, 28,42 and 56 plants/m2. Above-ground dry matter (DM) production at maturity was largest in safflower (439 g/m2) and smallest in chickpea (253 gIm2). Seed yield was 144 g/m2 for wheat, 100 g/m2 for safflower and 95 g/m2 for chickpea. DM production was closely related to accumulated growing day degrees but the relation weakened with diminishing soil water availability towards maturity. DM production increased with increasing PPD in all crops. However, only chickpea gave a positive seed yield response to PPD. Safflower extracted more water (375 mm) from the top 2 m of the soil profile than wheat (212 mm) and chickpea (195 mm). Overall water use efficiency (WUE) for DM and seed yield was low; wheat had the highest values (1.91 and 0.68 g/m2/mm respectively) and safflower the lowest (1.15 and 0.26 g/m2/mm). We suggest the low values of WUE may be in part a feature of the dry season, with high evaporative demand immediately preceding maturity. Based on 1988 market prices, the best economic returns would be from chickpea, followed closely by safflower and then wheat.