Phosphorus nutrition of large-seeded chickpea cv. Macarena (Cicer arietinum) in the Ord River Irrigation Area, Western Australia

Abstract

The phosphorus (P) nutrition of largeseeded chickpea (Cicer arietinum) cv. Macarena grown on Cununurra clay in the Ord River Irrigation Area was studied in field trials and by sampling commercial crops. Response to applied and residual P on a previously uncropped site (site 1) was examined over 2 growing seasons and to applied P on a site with a history of cropping (site 2) in 1 season. At site 1, yield increased with application of up to 50 kg P/ha in the first year and 100 kg P/ha in the second year. There was no significant response in the second year to the P applied in the previous season, probably because of rapid fixation of P in Cununurra clay. At site 2, with a residual soil P level of 24 ¦g/g (HCO3), no growth response to applied P was observed. The survey of commercial crops included determination of P in soil, foliage, and seed, and the recording of phosphatic fertilisers applied. The data indicate that excessive P fertiliser is applied to many chickpea crops, with only a few crops being inadequately supplied.