ORIGINAL ARTICLE Evaluation the allelopathic effect of bindweed (Convolvulus arvensis L.) on germination and seedling growth of millet and basil

Evaluation the allelopathic effect of bindweed (Convolvulus arvensis L.) on germination and seedling growth of millet and basil ABSTRACT In order to study the allelopathic effect of different vegetative parts of bindweed on millet and basil seed germination and growth characteristics, two separate laboratory experiments were conducted on Agricultural Faculty of Shahid Chamran University of Ahvaz in 2010. The experimental design was completely randomized, with three replications. The treatments were arranged in a 4 × 3 factorial design including different extract of bindweed vegetative parts (i.e. stem (P stem ), leaf (P leaf ) and whole vegetative parts (P stem + P leaf = P total )) and extract concentration in four levels including distilled water (control), 33% w/v (AE 33% ), 66% w/v (AE 66% ) and 100% w/v (AE 100% ). In this study germination percent, seed germination rate, radicle and plumule length, seed vigor index, radicle to plumule ratio and radicle and plumule dry weight of millet and basil were measured. Among different extracted parts, P total of bindweed had the highest inhibitory effect on millet and basil germination and growth characters. AE 100% had the highest inhibitory effects on millet and basil germination and seedling growth as compared with control. In contrast, AE 33% had the lowest inhibitory effect on both plants. Therefore, inhibitory effects of bindweed increased by increasing extract concentration. Radicle length and dry weight was more sensitive to bindweed allelochemical materials than plumule length and dry weight. Also, germination percent of basil was lower than millet as influenced by allelopathic effects. Radicle and plumule dry weight less affected than other studied characters to different extracts

ORIGINAL ARTICLE Effect of Different Green Manure Crops and Nitrogen Levelson Biomass Production Efficiency and Nitrogen Concentration in Wheat(TriticumaestivumL.) and Soil

ABSTRACT Utilization of green manure crops along with nitrogen fertilizer may balance requirement of soil and plants to nitrogen and increase nitrogen availability for succeeding crops. In order to study the effect of green manure (GM) crops and nitrogen (N) levels on grain, straw and soil nitrogen concentration and biomass production efficiency (BPE), a field experiment was conducted on Agricultural Faculty of ShahidChamran University of Ahvaz during 2010-2011. The experimental design was split plot based on RCB with three replications. Main plot including nitrogen rates (i.e. 0, 50, 100, 150 kg.ha -1 ) and sub-plot including green manure crops (i.e. fallow, millet, sesbania, amaranth, cowpea and mung bean). Our result showed that, both GM crops and N levels had significant effect on BPE, wheat grain, straw and soil N concentration. The effect of GM and N interaction was significant only on soil N concentration. Relationship BPE and wheat grain N concentration with N fertilizer levels was linear. In contrast, relationship of wheat straw N concentration as well as soil N concentration with N fertilizer levels was non-linear. Biomass production efficiency diminished as N fertilizer rates increased, while other studied factors increased with increase of N fertilizer rates. Highest grain and soil N concentration obtained with legume GM crops (sesbania and cowpea, respectively) application and highest BPE and straw N concentration obtained after fallow treatment. Generally, result of this study indicated that, legume GM crops can be better than non-legume GM crops due to atmospheric N fixation and release suitable nutrients especially N for subsequent crops