نشریه فیزیولوژی گیاهان زراعی
پیاپی 23 (پاییز 1393)

In order to investigate the effect of organic nitrogen on fluorescence changes of photosynthetic pigments of Hamedani alfalfa under drought conditions, this experiment as factorial was conducted in a completely randomized design with three replications. The treatments of experiment consisted of drought tension in three levels of 35, 60 and 85 percentage of field capacity and nitrogen fertilizer at four levels of without fertilizer, 30, 60 and 90 kilogram nitrogen per hectare. The results showed, the interaction of nitrogen at drought at one percent level on chlorophyll a concentration, total chlorophyll and at the level of 5 percent on chlorophyll b concentration, the ratio of chlorophyll a to b and carotenoids was significant. With increasing levels of dryness the amount of chlorophyll a concentration, b, total and carotenoids was reduced but ratio chlorophyll a to b was increased. Nitrogen consumption improved photosynthetic pigments so that chlorophyll a concentration, chlorophyll b, total chlorophyll increased with nitrogen consumption and the ratio of chlorophylls and the amount of carotenoids were reduced. Nitrogen fertilizer on the maximum fluorescence (Fm), quantum yield (Fv / Fm) in pre-tension and on the minimum fluorescence (Fo) and (Fv / Fm) in after three days tension and on (Fv / Fm) in a week after tension had a significant effect. Drought tension had a significant effect only on (Fo) and (Fm) in three days after tension and on (Fo) and (Fv / Fm) in a week after tension. The minimum and maximum amount of protein was obtained in the conditions of without using nitrogen (4.79 milligram on gram wet weight) and consumption of 90 kilogram nitrogen per hectare (10/06 milligram on gram wet weight) was obtained. Nitrogen interaction in dryness, on stem height and plant dry weight was also significant. In tension conditions, stem height and plant dry weight reduced.

In order to investigate the effect of plant growth stimulants at different times on some qualitative and quantitative features of maize Single Cross 260, this experiment was conducted as factorial in a completely randomized blocks design with three replications at Agriculture and Natural Resources Center of Mahabad city in 2012 cropping year. The first factor was the application of Amino acids in four levels, foliar application with water (control), foliar application with Hiomin Fort, foliar application with Amino acid Aminol Fort and foliar application with fertilizer biological power k and the second factor consumption different times in three levels of foliar application at eight-leaf stage, foliar application at appearance of Tassel and, foliar application at eight leaf stage appearance of Tassel. The results of variance analysis indicated, the treatments effect of foliar application and the time of foliar application on all the traits was statistically significant at one percentage probable level. The highest protein yield was obtained in interaction of Hiomin Fort solution in the time of eight leaf appearance of Tassel (455/5 per hectare) and the lowest protein yield in interaction of control level of foliar application in the time of eight leaf (203/8 kilogram per hectare).The highest grain yield (5574 kilogram per hectare)was related to the interaction of foliar application with Hiomin Fort solution in the time of eight leaf foliar application appearance of Tassel and the lowest was related to control level (foliar application with water) at the time of eight leaf foliar application (3160 kilogram per hectare). The obtained results of this experiment showed application of biological fertilizer and Amino acids at the eight leaf appearance of Tassel, cause increasing the biological and grain yield in maize single cross 260.

In order to study the effect of drought tension effect at the end of season on grain yield and the assessment of lines tolerance to tension, this experiment was conducted in a randomized complete blocks design in the Agricultural Research station of Kheirabad Zanjan. In this experiment 14 genotypes of bread wheat selected from the breeding experiments of cereals sector of Zanjan Agricultural Research center were under irrigated and end seasonal drought tension in two separate experiments. Results of variance analysis showed that in the absence of tension conditions between genotypes for all traits of genotypes except biological yield there was significant difference at the probable level of one percent and biological yield at the probable level of five percent. Results of variance analysis in drought conditions showed that between all genotypes traits except grain yield at the probable level of one percent and regarding to grain yield trait at the probable level of five percent there was significant difference. Based on tolerance indices (STI, MP and GMP) genotypes 11, 6, 9 and 4 were more tolerant genotypes. Among the mentioned genotypes, genotype 11 which had the highest indices amount of STI=0/98, MP=4765/05 and GMP=4723/11 and has had the highest yield under drought tension conditions (Ys) (4134/26 kilogram per hectare), was selected as a high-yielding and tolerant genotype.

In order to investigate the effect of biological fertilizers on grain yield¡ yield components¡ the efficiency of precipitation and productivity effort of chickpea as autumn plantation¡ this experiment as factorial by using mycorrhiza inoculation factors (inoculation and non-inoculation)¡ bio-phosphate inoculation (inoculation and non-inoculation) and vermicompost (without fertilizer¡ 6 and 12 tons per hectare) in completely randomized blocks design with 4 replications was carried out during 2009-2010 cropping year in Agriculture Research Station of Sarab Changayi (Affiliate with Agriculture Research Center and Natural Resources of Lorestan province). The means were compared by Duncan test at probable level of five percentage. The results showed that the highest grain yield (2497 kilogram per hectare)¡ biological yield (7720.4 kilogram per hectare)¡ one hundred-grain weight (28.5g)¡ grain harvest index (32.2 percentage)¡ productivity effort (49) and efficiency of precipitation (5.1 kilogram per millimeter) was obtained in mycorrhiza inoculation. The bio-phosphate inoculation showed significant effect on grain yield and efficiency of precipitation so that the highest grain yield (2310.4 kilogram per hectare) and water productivity (4.7 kilogram per millimeter) was obtained of bio-phosphate inoculation. Also¡ Vermicompost factor had significant effect on grain yield¡ biological yield and efficiency of precipitation and the highest grain yield (2373.7 kilogram per hectare)¡ biological yield (8174.9 kilogram per hectare) and efficiency of precipitation (4.8 kilogram per millimeter) in third level of vermicompost (12tons per hectare) was achieved. In this research¡ the effect of interaction two factors mycorrhiza inoculation and bio-phosphate inoculation on grain yield and harvest index and two factors of mycorrhiza inoculation and vermicompost on grain yield¡ biological yield and efficiency of precipitation was significant.

In order to evaluate the rapeseed cultivars regarding to the characteristics such as earliness, lodging resistance and also high yield potential, eight rapeseed cultivars were investigated in a randomized complete blocks design with three replications in Rice Research Institute of Iran in 2005-6 cropping year. Results of analysis of variance showed significant difference among cultivars regarding to all studied traits. The grain yield mean comparison of cultivars showed that cultivar Hyola308, Hyola420 and RGS-003, respectively, with average yields of 3/44, 3/01 and 2/84 tons per hectare were superior than the other cultivars so that the Hyola308 compared to Syn-3 had a superiority of a 52/62 percent. In terms of earliness among the studied cultivars, hybrid Hyola330 had a 13/78 percentage superiority than the Option504 delayed cultivar. Also, the investigation of grain yield components showed that the highest number of seeds per pod (26/23 seeds) was associated to Syn-3 and the highest number of pods per plant was related to the RGS-003 cultivar with 117 pods. Grain yield had a significant and positive correlation with flowering period duration to maturity and had a significant and negative correlation with pod length. According to the path analysis results, flowering period trait to maturity had the most direct positive effect on grain yield while traits the length of pod and pod number per main stem had a negative direct effect on grain yield.

In order to investigate the effect of drought tension on the activity of glutathione reductase and ascorbate peroxidase antioxidant enzymes in three groups of sensitive, intermediate and tolerant to drought winter wheat at the flowering stage under normal irrigation conditions (90%FC), moderate drought tension (60%FC) and severe drought tension (30%FC) was applied. The experiment was conducted in factorial form based on completely randomized design and in order to investigate the effect of tension in flowering stage above mentioned enzymes activity was measured by spectrophotometrical assessment technique. The data analysis of variance showed that the effect of drought tension was significant on the activity of these enzymes. Significant difference between the groups of tolerant, intermediate and sensitive wheat was significant only for glutathione reductase enzyme. Interaction between drought tension and wheat groups was significant for both glutathione reductase and ascorbate peroxidase enzymes and the response of intermediate genotypes was identical and significant without difference for both enzymes in environmental conditions. While genotypes belonging to the tolerant and sensitive group showed significant increasing activity and with increasing the amount of tension, this increasing was further. Compared with ascorbate peroxidase, glutathione reductase enzyme showed more activity increasing in drought tension conditions, thus this enzyme can be considered as one of the important enzymes to increase tolerance wheat against the tension due to the dryness.

Drought tension is one of the main factors restricting the growth of crop plants and compounds such as salicylic acid can affect drought tolerance in plants. In this research the effect of cut irrigation tension and foliar application of salicylic acid on growth, yield, yield components and oil percentage of three safflower cultivars was studied in a split-plot factorial layout with randomized complete blocks design with three replications in Agriculture and Natural Resources Research Station in Gorizeh Sanandaj. In this experiment irrigation treatment as the main factor in three levels: total irrigation as control, cut irrigation practices at vegetative stage and cut irrigation practices at reproductive stage and three cultivars of safflower Sina, Faraman and Isfahan landrace and three levels of salicylic acid: without foliar application, 50 milligram per liter and 100 milligram per liter as foliar application were considered in sub-plots at the beginning of vegetative stage .The results showed that cut irrigation practices caused reduction in plant dry weigh, primary branch number, grain yield, number of capitol in plant, number of seed in capitol, one thousand-grain weight and oil percent. Faraman cultivar had the highest number of primary branch (14/33) and Sina cultivar the highest number of seed per Capitol (31/30) and the lowest amount of plant dry biomass (22/80) was allocated to Isfahan landrace cultivar. On the other hand foliar application Salicylic acid by concentration 100 milligram per liter led to the increasing the primary branch number and one thousand-grain weight and in Faraman cultivar caused increasing the grain yield (1502 kilogram per hectare) and the number of capital per plant (58). Plant dry weight, number of seeds per capitol and oil percentage were not affected significantly by foliar application of salicylic acid.

In order to investigate the effect of vermicompost biofertilizer and plant density on yield and yield components of second crop soybean (summer crop) in Khorramabad, this experiment was conducted at the research farm of the Islamic Azad University of Khorramabad Branch in the summer of 2012. This experiment in form of factorial including four levels of vermicompost fertilizer (control, 5, 10 and 15 tons per hectare) and four plant density (50, 25, 16/6 and 12/5 plant per square meter) was conducted in a randomized complete blocks design with three replications. The results indicated that the vermicompost biofertilizer was significant on the grain yield, harvest index, number of pods per plant, one thousand- grain weight and number of pods per square meter at five percent probability level. The effect of density was significant on all traits except seeds number per pod, one- thousand grain weight and harvest index and the interaction of these two factors was significant on the grain yield, number of pods per plant, number of seeds per plant and number of pods per square meter. The comparison of means showed, with the increase in the use of vermicompost fertilizer, the grain yield was increased so that use of 15 tons per hectare produced the highest grain yield (2231 kilogram per hectare) and use of five tons per hectare of vermicompost produced the lowest grain yield (1682 kilogram per hectare). Also, with the increase in plant density, the grain yield was decreased, so that the density of 50 plants per square meter, produced the highest grain yield (2302 kilogram per hectare) and the density of 12/5 plants per square meter, produced the lowest grain yield (1628 kilogram per hectare). In general and with regard to the obtained results, the highest grain yield was achieved in the use of 15 tons per hectare of vermicompost and in the density of 50 plants per square meter.