عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In order to investigate the response of castor bean (Ricinus communis) to cover crops and organic fertilizers, a field experiment was conducted as split plot based on complete randomized block design with three replications at the Agricultural Research Station of Ferdowsi University of Mashhad during growing season of 2009. Four cover crops (Persian clover (Trifolium resupinatum), cantaloupe (Trigonella foenum-graecum L.), hairy vetch (Vicia villosa) ,grass pea (Lathyrus savivus) and control) and three types of organic fertilizers (nitroxin, phosphate suloblizing bacteria and vermicompost and control (without any fertilizer)) were allocated to main and sub plots, respectively. The results indicated that hairy vetch and control had the highest and the lowest effects on the weed biomass, respectively. Organic fertilizers was significant on Leaf Area Index (LAI), Total Dry Matter (DM) , Crop Growth Rate, plant height, inflorescences height, number of capsules per plant, number of grains per plant,100 seed weight, seed yield and oil percentage of castor . Also, the interaction effects between cover crop and organic fertilizer on quantity and quality characteristics of castor bean was not significant. The maximum and the minimum LAI and DM accumulation were obtained at 85 days after plant emergence in vermicompost (2.15, 693.3 (g.m-2)) and control (0.88, 313 (g m-2)), respectively. The highest plant height, inflorescences hight, number of capsules per plant, number of grains per plant, seed yield (670 kg.ha-1) and oil percentage of castor (33/9%) were achieved in vermicompost. This study showed that the applicatuion of suitable organic fertilizer could increase the yield and quality criteria of castor bean.