Effects of Nitrogen Rates on Critical Period of Natural Weed Interference on Barley Yield (Hordeum vulgare L. var. Makoei)

Effects of nitrogen rates on critical period of natural weed interference and yield of barley (Hordeum vulgare L.) were studied during 2006 and 2007 at the Agricultural Research Station, University of Tabriz, Iran. The experiment was carried out as split-plot, based on randomized complete block design with three replications. Nitrogen levels (0, 40, 60 and 120 kg/ha) were allocated to the main plots and 10 natural weed interference periods (two sets) were assigned to subplots. In the first set, the plots were kept weed-free up to Em (Emergence - 1st leaf emerged), El5 (5th leaf unfolded), Ti (Tillering - Main shoot and 3 tillers), Se (Stem elongation - 5th node detectable) and Ea em (Ear emergence - Emergence of head complete) growth stages (GS), corresponding to 10, 15, 23, 35 and 59 Zadok’s scales, respectively, by hand weeding. In the second set, plots were left weed infested up to the corresponding periods and subsequently kept weed free. Weed density was 161 plants per square meter in the control plots. Results showed that grain yield decreased with increasing weed interfrence duration. Full-season weed infestation decreased barley grain yield 42.51% as compared with the control. The constructed models indicated that in order to prevent a 5% grain yield loss, weeds at 0, 40, 80 and 120kg N/ha must be removed from the fields after 20.5, 29.6, 31.9 and 30.5 days from emergence (DAE), respectively. Barley required 130.5, 106.7, 105.2 and 109.8 days weed free period to prevent a 5% grain yield loss under given nitrogen rates, respectively. An increase in the nitrogen levels enhanced barley tolerance to weed infestation. The growth and grain yield of barley were also increased by nitrogen application in the sustainable level, however, weed dry weight was not affected. The absence or more reductions in nitrogen use may warrant more intensive weed management. Furthermore, more reductions in the nitrogen level before barley planting may cause the need for more immediate and long period weed control

Some Morphological Characters and Yield of Common Field Bean (Vicia faba.L)

To evalauate the influences of irrigation time with wastewater of Iran mayhes factory (producing leaven) on some morphological characters and yield of faba bean, a factorial experiment carried out on the base of randomized complete block design (CRBD) in Iran Mayehs factory farm in spring2012. Experimental factors consisted of irrigation times at 3 levels I1 = one irrigation with determined amount of wastewater, I2 = two irrigations with determined amount of wastewater, I3 = irrigation during the growth period of plants with determined amount of wastewater) and wastewater concentration at 6 levels (P0 = irrigation with normal water (control), P15=15% wastewaters + normal water, P30= 30% wastewaters + normal, P45= 45% wastewaters + normal water, P60= 60% wastewaters + normal water, P100= all wastewater) with three replications. Results showed that the effect irrigation numbers on traits such as plant height, number of pods per plant and seed yield was significant. Results also revealed that the effect of weastwater concentration on1000seed weight was significant. The interaction of number of irrigations by weastwater concentrations on stem dry weight was also signification. Evaluation of different treatments showed that 45 percent concentration of wastewater was increased traits under study. It seems, that controlled irrigation of bean with wastewater of factory (producing yeast) can be effective in improving its yield in the region

The Effects of Different Planting Time of Cover Crops and Medical Plant on Grian Yield and Yield Components of Maize and Weed Biomass

In order to study different times of cultivating and type of medical and cover plants on performance and weed biomass of corn (single cross 504), the experiment was carried out in 2010-2011 in research farm of the agriculture faculty of university of Tabriz. The experiment was carried out in a factorial arrangement with the base of  randomized complete block design in three repetications. The treatments of this experiment included type of medical and cover plant in 4 levels (Clover, hairy vetch, basil and dill) as first factorial and time of cultivating cover and medical plant in tow levels(synchronic cultivation with corn and cultivation 15 days after corn cultivation) as second factorial. The results showed that the ear height, the number of grain row per ear and yield of grain lied under effect of the time of cultivation and the type of cover plants as the highest amount of these traits were seen in treatment of the corn with clover and the lowest amount were seen in the treatment of the corn with dill. Treatment composition of  cover plant × the time of cultivation on ear diameter and weight of 100 grain was significant and in both traits, ear diameter and weigh of 100 grain, the treatment of synchronic cultivation of corn with clover and the treatment of dill with 15 days delay in comparison of the cultivation of corn had the highest and lowest amount, respectively. Also, the highest weed biomass was seen in dill treatment with 15 delay than corn cultivation and the lowest amount was seen in synchronic cultivation of clover with corn

Evaluation of Water Use Efficiency and Grain Yield of Sesame Cultivars as a Second Crop Under Different Irrigation Regimes

This 2-year research was carried out in Ramhormoz to evaluate the effect of different irrigation regimes on water use efficiency (WUE) and grain yield of sesame cultivars. The experiments were arranged as spilit plot based on RCB design in four replications with irrigation treatments (I1, I2, I3 and I4: irrigation after 150, 200, 250 and 300 mm evaporation from class-A pan) in main plots and sesame cultivars (Yellow witte, TN238, TS3, Safiabadi and local cultivar of Ramhormoz) in subplots. Plant height, leaves per plant, biological yield and grain yield were decreased with increasing the severity of water deficit. All these traits were positively correlated with each other, suggesting that a decline in one of them could have a deleterious effect on sesame performance in the field. TS3 was a superior cultivar in plant height, biological and grain yields under all irrigation treatments. The harvest index of all sesame cultivars was increased with decreasing water availability. Thus, water limitation reduces biological yield more than grain yield in sesame. TS3 had the highest WUE in both years. The highest WUE was obtained under severe water deficit, indicating that sesame can produce acceptable yield with low water consumption

Evaluation of Bitter Vetch Lines Under Irrigated and Rainfed Conditions

In order to determine the most promising lines of bitter vetch regarding drought tolerance in rainfed areas, an experiment was conducted with 16 lines, under irrigated and rainfed conditions at Dryland Agriculture Research Institute, Maragheh. A randomized complete block design with three replications was used for each experiment. Analysis of variance for both rainfed and irrigated conditions showed that there were significant differences between lines for all studied traits. Combined analysis of variance indicated significant differences between two environments for all traits except plant height. Genotype × environment interaction was significant for all traits, except for plant height, pod number per plant and seed number per pod. Comparing means under irrigated and rainfed conditions showed that Sel 2518 had the lowest number of days to flowering and Sel 2515 and Sel 2516 had shorter period of grain filling. Local bitter vetch possessed the highest plant height, biomass, number of pods per plant and seed yield. Biomass, number of pods per plant and plant height had highest correlations with seed yield in both conditions. According to three drought tolerance indices (STI, GMO and MP), the local landrace was recognized as the most drought tolerant line with ability to produce highest yield in both rainfed and irrigated environments. This landrace was separated from other lines in the cluster analysis. In some cases, lines Sel 2644 and Sel 2647, originated from Bulgaria, were grouped with the local landrace. The results indicate that the local landrace was more productive than other lines under study and therefore, it is possible to identify suitable varieties for cultivation by evaluating different landraces of bitter vetc

Effect of Foliar Application of Iron, Zinc and Manganese Micronutrients on Yield and Yield Components and Seed Oil of Pot Marigold ) Calendula officinalis L.)

Although micronutrients effect on growth and yield of different plants has been intensively investigated, but there is limited information on its effect on grain yield and seed oil content of pot marigold) Calendula officinalis L.). In order to investigate the effects of micronutrients (Fe, Zn and Mn) spraying on yield and yield components and seed oil of pot marigold, a field experiment was conducted based on randomized complete block design with three replications at the Research Farm of Payame Noor University of Nagadeh in 2010. Treatments included Fe, Zn, Mn, mixed solutions of these elements (Fe+Zn, Fe+Mn, Zn+Mn, Fe+Zn+Mn) and control (water). Treatments were applied in 2 g/litter twice at stem elongation and early flowering stages. Different traits such as plant height, number of capitol per plant, number seed per capitol, thousand seed weight, biological yield, seed yield, seed oil percentage and oil Yield were recorded. The results showed that foliar application of micronutrients had significant effects on all of these traits. Yield components, seed yield, oil percentage and yield were enhanced by foliar application, compared with control (untreated plants). The maximum number seed per capitol, thousand seed weight and biological yield were relevant to Fe treatment. The highest numbers of capitol per plant and seed yield (643.33 kg.ha-1) were relevant to Zn+Fe treatment and the maximum oil yield (124.20 kg.ha-1) was produced by Zn+ Fe+ Mn treatment. Seed yield and oil yield increased by 31.27% and 44.18% yields more than control, respectively. It can be concluded that, foliar application of micronutrients had positive effects to obtain high yield and oil of pot marigold

The Effect of Organic, Biologic and Chemical Fertilizers on Quantitative and Qualitative Characteristics of Sweet Basil (Ocimum basilicum L.)

Sweet basil (Ocimum basilicum L.) is one of the most important medicinal plants that its essential oil used in different medicinal industries. In this research, effects of different types of fertilizers were evaluated on quantitative and qualitative characteristics of basil. The research was conducted under field condition in complete randomized block design with three replications. The treatments included vermicompost, livestock manure chemical fertilizer, biofertilizer (Azospirillum/ Azotobacter), combinations of vermicompost and 50% chemical fertilizer, combinations of biofertilizers and 50% chemical fertilizer, manure and control. The highest dry yield in first and second harvest observed in combinations of biofertilizer and 50% chemical fertilizer. Results showed highest essential oil content obtained in chemical fertilizer and combinations of biofertilizer and 50% chemical fertilizer. According to the results, application of chemical fertilizer, biofertilizer and combinations of biofertilizer and 50% chemical fertilizer increased essential oil yield to 41%, 33% and 38%, respectively. Identification of essential oil components showed that content of Eugenol and Methyl chavicol increased with application of nitrogen fertilizers. It is concluded that application of biofertilizers enhanced quantitative and qualitative characteristics in this plant. Generally, it seems that using of biofertilizers could improve basil performance in addition to reduction of environmental pollution

The Response of Chickpea Cultivars to Field Water Deficit

An experiment was carried out in 2006 to investigate the effects of different irrigation regimes (I1, I2, I3 and I4 for irrigation after 80, 110, 140 and 170 mm evaporation from class A pan, respectively) on ground cover, yield and yield components of four chickpea cultivars (Arman, ILC and Jam from kabuli type and Pirooz from desi type) in the field. In most stages of crop growth and development, the ground cover of ILC under different irrigation regimes was higher than that of the other cultivars. The ground cover of all chickpea cultivars was reduced, as water deficit severity increased. Grain yield and yield components were significantly affected by irrigation regimes. Mean grains per plant, 1000 grain weight and grain yield per unit area for I4 were significantly lower than those for other irrigation regimes, but these traits did not differ significantly among I1, I2 and I3. Thus, irrigation after 140 mm evaporation from class A pan could be a suitable irrigation regime for chickpea cultivars, when water resources are limited. Grains per plant did not differ significantly among chickpea cultivars. In comparison, the largest and the smallest grains were obtained from ILC and Pirooz, respectively. In general, mean 1000 grain weight of kabuli type cultivars was higher than that of desi type cultivar. The superiority of ILC in ground cover and 1000 grain weight resulted in higher grain yield, compared to other cultivars. However, no significant differences in grain yield of Arman, Jam and Pirooz were observed. Interaction of cultivar x irrigation for ground cover, grain weight and grain yield per unit area was not significant, indicating that ILC was a superior cultivar under both well and limited irrigation conditions