) HELIANTHUS ANNUS( و آفتابگردان )glycine maxl.( ، سويا )SORGHUM HALEPENSE( بررسي اللوپاتيك ريشه لاينهاي نخود سياه بر جوانه زني و رشد اوليه سورگوم

Evaluation of Allelopathic Effects of Chickpea Root Extracts on Germination and Early Growth of Sorghum (Sorghum halepense), Soybean (Glycine max L.) and Sunflower (Helianthus annul)

The allelopathic effects of chickpea root extracts were studied on germination and early growth of crops in rotation: Five accessions of chickpea were sown in pots and were followed by three crops (sorghum, soybean and sunflower). Crops were planted in three sowing intervals (immediately after physiological ripening of chickpea, two weeks later and four weeks later). Experimental treatments were arranged as split-split plot and were compared in a Completely Randomized Block Design with three replications. Seed germination rate, germination percent, plant height, shoot dry weight and shootiroot ratio of crops were affected by different treatments. Seed germination rate of crops after chickpea line 5436 was significantly reduced after four weeks. Seed germination percentage increased as the crops were sown two weeks after chickpea physiological ripening. The crop height followed an increasing trend as they were sown later after physiological ripening of chickpea lines. The root extracts of line 4488 significantly reduced soybean biomass production. However, under the same conditions it enhanced biomass production of sorghum. The severity of chickpea root extracts inhibitory effects on crops were dependent on chickpea cultivar as well as the genetic characteristics of crops in rotation. Deferment in sowing date of crops from harvest time of chickpea decreased the deterious effects of chickpea root extracts on subsequent crops.