Effect of Plant Density and Harvesting Time on Oil and Protein Yield of Kochia (Kochia scoparia L. Schrad) under Saline Irrigation Conditions

Production of halophytes using saline waters and soils, and feeding livestock with them, is one of the most sustainable ways of desert ecosystems conservation and food production for people living in these areas. A field experiment was conducted at Salinity Research Station, Ferdowsi University of Mashhad, in 2007 to evaluate the effect of planting density and harvesting time on oil and protein yield of Kochia. Treatments were arranged as a split-plot based on a randomized complete block design with three replications. Planting density (10, 20, 30 and 40 plants m-2) as assigned to main plots and two dates of harvesting (after 50% flowering and full maturity) constituted the sub-plots. Plant density had a significant effect on grain yield, mean seed weight, harvest index, oil yield, oil content and protein yield at maturity stage. Forage and protein yield were also affected by plant density at the harvest date of 50% flowering. Total dry matter, protein yield and percentage differed significantly between the two harvest dates. The greatest grain yield (2590 kg ha-1) and oil yield (357.7 kg ha-1) were achieved from 20 plants m-2, whereas those from 10 plants m-2 were minimal. Maximum protein yield (3390 Kg ha-1) was obtained from the planting density of 30 plants m-2 at 50% flowering stage. Based on the results of this study, the best qualitative yields for Kochia could be obtained from a planting density of 30 plants m-2 after 50% flowering but one may recommend planting Kochia at 20 plants m-2 for a high grain or oil production.