Abstract
The growth and yield potential of soybean and the effects of mulching on desert sand were evaluated in relation to N accumulation in nodules. The experiment was conducted in concrete framed plots filled with sand obtained from the Dzungar desert or the normal field soil in Shihezi, Xinjiang, China. Drip irrigation with or without mulch was adopted for the experimental plots. The mean soil temperature in the sand plot with mulch was the highest among the plots during the early growth stages. The relative ureide-N content in the soil plots varied from 23.2% at the full flowering stage (R2) to 37.6% at the beginning of the maturity stage (R7). The sand plots showed higher values than the soil plots ranging from 48.7% at R2 to 80.5% at R7, indicating active N2 fixation by nodules. Seed yield did not show a significant difference between the soil and the sand plots. It ranged from 394 g m-2 in the soil plot without mulch to 472 g m-2 in the sand plots with mulch. The results suggested the possibility of extending soybean cultivation into marginal areas of deserts, provided that adequate water was available for drip irrigation and there was active nodulation.
