جستجوی مقالات مرتبط با کلیدواژه « اجزای عملکرد دانه » در نشریات گروه « زراعت »

Basil with numerous medicinal characteristics is one of the most important plants of the mint family (Lamiaceae). Among the factors affecting the growth and development and the production of effective substances of medicinal and aromatic plants is water, which is more effective than other institutions for reduction. Research has shown that salicylic acid makes plants resistant to environmental stresses. Therefore, in order to investigate the effect of foliar spraying of salicylic acid on the quantitative and qualitative characteristics of basil plants under the influence of drought stress, an experiment was conducted in the form of split plots based on randomized complete block design in 3 replications in a private farm located in Mahdasht area of Karaj city in 1394-1395 and 1395-1396. Irrigation in 4 levels: I1: 100%, I2: 80%, I3: 60% and I4: 40%. The volume of water required in the main plots and salicylic acid in 5 levels: S1: No application (spraying solution with water net as control), S2: foliar spraying with a concentration of 50 μM, S3: 100 μM, S4: μM and S5: 200 μM were placed in the subplots. The results showed that the water deficit caused a decrease in the number of spikes per plant, the number of hazelnuts per plant, the number of seeds per hazelnut and the 100-seed weight, and the use of salicylic acid increased the number of spikes, the number of hazelnuts per plant and 100-seed weight. Under the influence of water deficit, biological and seed yield decreased and with increasing concentration of salicylic acid, biological and seed yield increased significantly. By increasing the concentration of salicylic acid in all humidity regimes, biological and seed yield also showed a significant increase. Also, the response of basil plant to salicylic acid under drought stress conditions was very significant compared to the conditions of supplying 100% of the plant's water needs (full irrigation). Finally, due to the adverse effect of drought stress on the growth and production of basil plant, it seems necessary to use salicylic acid to moderate drought stress.

To quantify the role of crop management practices on seed yield of soybean in Gorgan, 120 soybean farmers’ fields with different sowing dates and different management practices were randomly selected in Gorgan region in the north of Iran, in 2016, 2017 and 2018. Qualitative information was transformed to quantitative data. By using stepwise regression analysis a seed yield model was selected with two parameters including; delay in sowing date and number of irrigation during soybean growing season. The selected model explained 81% of the variation for seed yield. The model showed the importance of sowing date and irrigation for increasing seed yield of soybean in farmers’ fields in Gorgan region. There was negative significant linear relationship between biological and seed yield with delay in sowing date that explained 64% and 70% of the variation for these two characteristics, respectively. Each day delay in sowing date from May 22, biological and seed yield decreased 130 and 56 kg ha-1, respectively. The mean seed yield of farmers’ fields, with 0, 1, 2, 3, 4, 5 and 6 irrigation during growing season, was 955, 883, 1066, 1995, 1990, 2665 and 3769 kg ha-1, respectively. In Goragan region, soybean is planted usually from late may following harvest of winter crops such as wheat and canola. Under these environmental conditions, optimum crop management practices are required in soybean farmers’ fields to achieve high seed yield and sustainable production.

In order to yield comparison of eight cold barley promising lines including CB-85-19,CB-85-14, CB-85-9, CB-85-15 and CB-85-10 along with three barley varieties checks(Bahman, Makoui, valfager), these experiments were conducted using RCBD withthree replications in farmer field of Torbat-e-haydaria and Fariman during 2010-2011cropping season.During the stages of growth and development, the necessary records of agriculturaland morphological traits, including the dates of spike emergence, physiologicalmaturity, plant height and 1000 seeds weight, were evaluated and after harvesting,weighing and recording the seed yield of each line, variance analysis was carried out.A randomized complete block design was performed based on the grain yield. Theresults of combining analysis showed that there were significant differences (P< 0.05)between two experimental locations for grain yield and 1000 kernels weight. Inaddition, there was a significant difference for interaction of genotype × location on1000 kernels weight. The highest grain yield (6.242 t/ha) related to CB-85-10 barleygenotype which was produced from farmer’s field in Torbat-e-haydaria and Fariman.

Decreasing crop production due to the global climate change, especially simultaneous appearance of drought and high temperature is being rose. Hence, understanding relationships among genotypes characteristics under drought stress will be crucial for selection and breeding of drought tolerant cultivars. In this research, in order to grouping and the study of genetic variability of safflower (Carthamus tinctorious L.) genotypes, 15 genotypes were cultivated based on a completely randomized design in Lorestan University (Khorramabad, Iran) Research Farm under normal and terminal season water deficit condition. Results of ANOVA and mean comparision showed significant differences among genotypes for studied traits under both conditions. The factor analysis technique introduced three factors under non-stress conditions which explained 79.40% of total variation. Factors I and II were named as grain yield component and efficiency, respectively. Similarly, three factors were intrtoduced under stress condition, and 59.09% of total variation was accounted by the first two factors. Factors I and II were described as grain yield and yield component factor, and growth and development factor, respectively. According to the cluster analysis, all genotypes were grouped into 3 groups in both normal and terminal season water deficit stress conditions. Totally, results of factor analysis, cluster analysis and mean comparison and also, stability of grain yield in both humidity conditions showed that genotype 6 (Syrian) could be introduced as a hopefull genotype for future breeding and agronomy programs.

In order to investigate the interaction between sodium nitroprusside and drought stress on photosynthetic pigments and their relationship with yield and yield components of rapeseed, an experiment was conducted during two cropping years (2015-16 and 2016-17) at Hamedan Agricultural and Natural Resources Research Center. The experiment was carried out as a factorial in randomized complete block design with three replications. Experimental factors were irrigation levels including full irrigation (control), irrigation termination from beginning silique stage and irrigation termination from grain filling stage, and four treatments of foliar application of sodium nitroprusside with concentrations of 0, 100, 200 and 300 μM. The results showed that irrigation termination significantly reduced the amounts of studied traits. Sodium nitroprusside foliar application increased the amounts of photosynthetic pigments, yield and grain yield components under drought stress and non-stress conditions. The highest and the lowest grain yield were obtained in the combination treatments of plant foliar application with 300 mM sodium nitroprusside and full irrigation (5129 kg/ha) and non-foliar application and irrigation interruption at the beginning silique stage (3396 kg/ha), respectively. The experiment indicated that sodium nitroprusside application can have positive effects on photosynthetic pigments, yield components and grain yield of rapeseed under drought stress and non-stress conditions, and therefore its application can greatly mitigate the adverse effects of drought stress in water deficit conditions.

Inoculation of crops with mycorrhiza fungi and growth-promoting bacteria, due to the high benefits (including increased root area and nitrogen fixation) increase the growth, and also nitrogen due to the important role that in crop growth and development directly increases the seed yield in crops. On the other hand, increasing competition between crops-weeds and reducing the access of crops to resources reduces seed yield. Therefore, this experiment was conducted with the aim of investigating the interaction of mycorrhiza, rhizobium inoculation and nitrogen fertilizer on soybean characteristics under weedy check and weed free conditions. This experiment was conducted in the city of Ali Abad Katoul in 2016. Treatments were included 1- Weed management at two levels of weed free and weedy check, 2- inoculation of biological fertilizer at four levels of non-application (control), inoculation of seeds with Bradyrhizobium japonicum, inoculation of seeds with mycorrhizal fungus Glomus mosseae and co-inoculation with Mycorrhiza and Rhizobium and 3- Application of nitrogen fertilizer (pure) from the source of urea fertilizer at three levels of zero (control), 25 and 50 kg / ha. In this experiment, leaf area and dry matter changes were measured during the growing season and grain yield, biological yield, number of pods per plant, number of seeds per plant and 100 seed weight in soybean plant was measured in Soybean plant (Katoul variety). The results of this experiment showed that the effect of biological fertilizer and the interaction of weed and chemical fertilizer on maximum soybean leaf area index was significant. So that, with increasing application of nitrogen fertilizer in weedy check and weed free treatments, the maximum leaf area index increased, but this increase was higher in weedy check tratments. Also, the results of this experiment showed that the effect of biological fertilizer, nitrogen fertilizer and weed management on yield components and seed yield was significant. So, with increasing application of nitrogen fertilizer, inoculation with biological fertilizer and weed control, number of pods per plant, 100 seed weight and number of seeds per plant increased. seed yield with weed control increased 22.2% and by using 50 kg of pure nitrogen, 16.3% was added to seed yield compared to control. Inoculation with mycorrhizal fungi and rhizobium also increased 8.6% and 13.2% of seed yield, respectively, as compared to the control. In general, the results showed improved growth conditions for soybean (weed control and the use of chemical and biological fertilizers) makes the leaf area and dry matter accumulation during the growing season increase. This increase in leaf area and dry matter accumulation cause increases in yield components of soybean and eventually increased seed yield.

Adjustment of plant density is an important base on light، water and soil nutrients for increasing seed yield. To determine of plant density in new red bean lines (Phaseolus vulgaris L.)، this experiment was conducted as factorial in randomized complete block design (RCBD) with three replications at Lordegan region (Chaharmahal and Bakhtiari province) in 2004-2005. Factors were new red bean lines (BRB188، ARS-R93003 and D81083) and plant densities (14. 8، 19. 1، 26. 6 and 44. 4 plant m-2). At during the growing season، it was measured plant height، seed yield and its components. Results showed that 100-seed weight، number of seed per pod and plant height had no difference among plant densities، but number of pod per plant decreased when plant density increased. Crop yield increased when plant density increased. Lines were different at plant height، 100-seed weight، number of pod per plant، number of seed per pod and seed yield. Results of two years showed ARS-R93003 and BRB188 lines were better lines and plant density should be between 26. 6 and 44. 4 plant m-2.

To study the effect of plant growth promoting bacteria (PGPR) and mineral nitrogen fertilizer on yield and yield components of three durum wheat cultivars, an experiment was conducted as a split factorial based on randomized complete block design with three replications in Dehloran Research Station in Ilam, Iran in 2011-2012 cropping season. Experimental factors consisted of durum wheat (Yavaroosm, Kharkheh and Simareh) was assigned to main plot and nitrogen fertilizers at 3 levels (40, 80 and 120 kg.ha-1) and bio-fertilizer (non-inoculation, inoculating with Azotobacter chroococcum, Azospirillum brasilense) to sub plot. Results of analysis of variance showed that among cultivars studied there were significantly differences at traits under study. Yavaroos had the highest plant height, 1000- grain weight, and biological yield. The highest plant height, 1000- grain weight, biological yield and protein content was obtained by application of 120 kg/ha nitrogen fertilizer, but there were not different effect between 80 and 120 kg/ha nitrogen fertilizer. Traits under study were affected by using bio-fertilizer. The highest plant height, number grain per spike, 1000- grain weight, grain yield were obtained from inoculation plants with bio-fertilizer. The effect of cultivar by nitrogen chemical fertilizer interaction had significant effect on plant height, number of grain per spike, 1000-grain weight, and spike per meter squared and grain yield. The highest grain yield was obtained from Yavaroos using 120 kg/ha and the lowest grain was observed from Simareh cultivar and 40 kg/ha. Interaction effect of cultivar and bio- fertilizer had significant effect on harvest index only. Nitrogen fertilizer by bio- fertilizer interaction had significant effect on only grain yield, spike/m-2 and grain yield. The highest grain yield was obtained from Yavaroos cultivar when it were inoculation with Azospirillum 120 kg/ha and the lowest grain yield observed Simareh cultivar when it was treated with 40 kg/ha.

This study was carried out as factorial arrangement in randomized complete block design with three replications in two years (2006 and 2007) in Jiroft and Kahnouj Agricultural Research Center, Jiroft, Iran. The first factor was eliminating of irrigation at different growth stages at five levels: 1- eliminating irrigation from 4-6 leaf stage to prior to flowering, 2- eliminating irrigation from 4-6 leaf stage to full flowering, 3- eliminating irrigation from flowering to the end of the growing season, 4- eliminating irrigation from 4-6 leaf stage to prior to flowering and from flowering until the end of the growing season, 5- Full irrigation based on 100 mm evaporation from class A pan (control), and the second factor was sesame genotypes, local Jiroft variety and JL-13 line. Branch plant-1, capsule plant-1, seed capsule-1, 1000 seed weight, seed oil content, plant height, biological yield, seed yield and harvest index were measured. Results showed that eliminating of irrigation at different growth stages significantly affected seed yield, capsule plant-1 and seed capsule-1, 1000 grain weight, branch plant-1, plant height, biological yield and harvest index. Eliminating of irrigation at different growth stages significantly reduced grain yield, yield components, branch plant-1, plant height, biological yield and harvest index. The least reduction rate in seed yield, yield components, lateral branches, plant height, biological yield and harvest index was recorded in eliminating of irrigation from 4-6 leaf stage to prior to flowering, and it had the highest seed yield following the control. Eliminating of irrigation from 4-6 leaf stage to prior to flowering and from flowering to the end of growing season had a considerable impact on seed yield and yield components and had the lowest seed yield. JL-13 line produced higher seed yield under stress and non-stress conditions.

Hull-less barley (Hordeum vulgare var coeleste L.) is one of varieties of common barley، which is used for feeding of poultry and animals. It is also useful for crop rotation. Appropriate sowing date and seed rate of hull-less barley are very important in Chaharmahal & Bakhtiari province. To determine effects of sowing date and seed rate on grain yield and yield components of local hull-less barley، field experiments were conducted at Shahrekord region (Iran) during 2003-04 and 2004-05 cropping seasons. Experiments in both years were factorial base on randomized complete block design، with three replications. Seed rates were 300، 400، 500 and 600 seed per m2 and sowing dates were 2، 17 Oct.، 1 and 16 Nov. Results showed that sowing date significantly affected on grain yield، number of spike per m2 and 1000-kernel weight. Grain yield decreased when sowing date was delayed، because number of spike per m2 and 1000-kernel weight decreased. At the other hand، grain yield at different plant densities was significant at 5% probability level. With increasing seed rate، number of spike per m2، 1000-kernel weight and grain yield increased. Overall، sowing date of 2 Oct. and seed rate of 400 seed per m2 are recommended to cultivate hull-less barley at Shahrekord region.

In order to study the phenological and morphological characteristics، comparison of yield and yield components، correlation between traits and determination of the parameters affecting seed yield، a field experiment was carried out at the Research Farm of Shahrekord University in 2007. Ten lentil genotypes were compared by a randomized complete block design with three replications. The analysis of variance indicated that there was a significant difference among genotypes for all evaluated traits. Considering significant negative correlation between growing degree days to physiological maturity and seed yield، early maturing genotypes such as genotypes Precoz and L3685، which could grow well before coinciding with high temperature will be produced high yield at Shahrekord climatic condition. Seed weight showed significant negative correlation with number of seeds per plant، number of seeds per pod and number of pods per plant. Since، correlation of number of seeds per plant and number of pods per plant with seed yield were positive، it is expected that the genotypes with lower seed weight could compensate the reduction in their yield by producing either more number of pods or seeds per plant. The results of standard multiple regression analysis between seed yield and its components and also the effects of morphological traits on seed yield showed 100 seeds weight، number of seeds per pod and number of pods per plant highly affected seed yield. Among yield component، 100 seeds weight showed high correlation with seed yield and also showed the maximum positive direct effect on it. Therefore، this component of yield may be considered as the best criteria for indirect selection to increase seed yield. Cluster analysis indicated that the genotypes were different for all studied characteristics and were grouped into high and low yielding genotypes and the high yielding genotypes were early maturing ones.

In order to select the suitable lines of red bean for Chahharmahal & Bakhtiari province, this experiment was conducted in Lordegan & Boldaji regions at 2001-2005. At the first year, single plants of local red bean (from Lordegan, Ardal, Boldaji, Dastgerd Emamzadeh and Gandoman regions) were selected at research farm for phenotypic characters, yield and yield components. At the second year, selected plants were sowed at lines with Naz, Sayyad and Lordegan local variety as controls and analyzed by histogram method. At the third and fourth years, selected lines were sowed in rectangular lattice design and analyzed. At fifth year, selected lines were sowed at randomized complete block design (RCBD) with three replications in two regions (Lordegan and Boldaji). Results of third year showed that L1, G17 and A15 lines were better than control Naz.

The cultivation of sunflower cultivar Armavirsky which has shown advantages under both rain fed and various irrigation system conditions in different areas, is also common in the Kurdestan province. In order to determine the sowing time and appropriate plant density of this cultivar in the region, the effects of three sowing times on 18th April, 29th April, and 9th May, and 6 density levels 10, 8, 7.1, 6.6, 5.7 and 4.7 plant/m2 respectively. The experiment was carried out as split plots in a randomized block design with three replicas. By analyzing the seed yield, oil percentage, number of seeds per cap, 1000-seed weight and the percentage of unfilled grains, it was found that with a delay in the sowing time the number and weight of seeds per cap, 1000 seed weight and seed yield decreased significantly but the percentage of unfilled grains increased. Although by decrease in plant density the traits related to the weight of grain per cap, 1000 seed weight, unfilled grains percentage and seed yield were increased, the number of grains per cap was decreased. Based on the findings of this experiment and in order to achieve the highest yield, the sowing time of 18th April and the plant density of 4.7 plants per square meter in the Ghorveh region of Kurdistan and other regions with similar ecological conditions are recommended.

To investigate the effects of methanol on the yield and the yield components of chickpea, a factorial experiment was conducted in the form of a randomized complete block design during three replications at the Research Field of Islamic Azad University Karaj Branch in the year 2008. Aqueous solutions 0 (control), 5, 10, 15, 20 and 25% (v/v) of methanol containing 0.2% glycine as well as the two varieties of ILC 482 and Azad were factors of this study. After flowering, these solutions were sprayed over the plant heads three times in one-week intervals. The results of the ANOVA indicated that the effects of solutions on yield, 100 seed weight, biological yield and plant height were significant. Also, significant differences on all the characteristics under investigation except plant height and harvest index were evident between the two varieties (ILC 482 and Azad). Interactive effects on biological yield, yield and 100 seed weight were respectively significant at 1%, 1% and 5%, probability levels. According to the results, the Azad variety on 10% of methanol application produced the highest yield (2482.6 kg/ha) which is an increase of 126% as compared with the control. The ILC 482 variety on 20% of methanol application reached the second rank after Azad by 2425.5 kg/ha and it improved 50% in relation to the control. The mentioned treatments had similar biological yield conditions. Highest 100 seed weight increased 40% and 30% respectively as with by 36.98 gr. for ILC 482 on the 10% of methanol and 35.03 gr. for Azad on the 5% at methanol. The application of methanol, as a source of carbon, increases more carbon fixation by inhibiting the photorespiration. Therefore, it can be a positive factor in improving the photosynthesis and increasing the yield of chickpea.

In order to determine the appropriate plant density of spotted bean in Yasouj, a field experiment was conducted in 2008 as a factorial in a randomized complete block design with three replications. Three spotted bean cultivars (Keshavarzi, Talash and Oshtori) were sown at five plant densities (10, 20, 30, 40 and 50 plant.m-2). Results showed that effect of plant density, cultivar and interaction between them on grain yield were significant. The maximum and minimum grain yield was obtained at 50 plant.m-2 (539.10 g.m-2) and 10 plant.m-2 (203.43 g.m-2), respectively. Number of pods per square meter and grain per pod at plant density of 50 plant.m-2 were higher than the other plant densities. Talash grain yield was higher than the other cultivars. Number of pods per square meter of Talash cultivar was higher than the other cultivars. Oshtori cultivar at plant density of 10 plant.m-2 with 161.7 g.m-2 and Talash cultivar at 50 plant.m-2 with 606.6 g.m-2 had maximum and minimum grain yield, respectively.

Apetalous flowers is an important morphological characteristic in rapeseed (Brassica napus L.), which cause response to higher planting population, more light transmition in canopy and radiation use efficiency, higher grain yield. In order to evaluate the effects of plant density and planting pattern on grain yield, yield components of apetalous and petalled rapeseed, a field experiment was conducted in Rice Research Institute of Iran, in 2005- 2006 cropping season. The experimental design was arranged in a split plot factorial in a randomized complete block design with three replications. Planting pattern (Rectangular and Square) as the main plots and two rapeseed cultivars (petalled = Hyola 401 and apetalous = Hylite 201) and plant density (33, 67 and 133 plants per square metrer) as subplots, respectively. The number of secondary branch per plant, plant height, number of siliques per plant, number of seeds per silique, silique length, oil percentage, thousand grain weight, harvest index, biological yield and grain yield were measured. Results showed that there were significant differences between treatments in measured traits. The average grain yield in apetalous cultivar was 14.6% higher than the petalled cultivar (3441.95 and 2938.06 Kg/ha, respectively). Plant density of 67 plants per unit area was determined to be the optimum plant density for two cultivars (4870 and 4290 Kg/ha respectively). Grain yield and number of siliques per plant in apetalous rapeseed was significantly higher than the petalled rapeseed (10 and 12%, respectively). This superiority was more evident at higher density (133 plants per unit area) i. e. 17.5 and 15.5%, respectively), indicating that apetalous cultivar has higher capability for higher plant population. In spite of non significant differences between harvest indices, right harvest indices of 4.5 and 11% in apetalous rapeseed in 67 and 133 plant densities, showed its higher capability for assimilate transport to grain. It seems that the main reason of superiority of apetalous rapeseed cultivar may be due to higher radiation use efficiency (RUE) compared to petalled cultivar (2.38 vs. 2.16 g.MJ-1, respectively)

In order to evaluate grain yield and associated characteristics in soybean (cv. Clark) under the conditions of drought stress and Bradyrhizobium japonicum strains, an experiment was carridout in 2003 & 2004 cropping seasons, using split plot arrangements based on randomized complete block design with three replications in Agriculture Research Statioin of Borujerd, Iran. Irrigation levels were assigned to the main plots (four levels); full irrigation, mild stress (85% plant water requirement), moderate stress (70% plant water requirement), severe stress (55% plant water requirement). Sub-plots were Bradyrhizobium japonicum strains (four levels); control, Helinitro, Rizoking, Nitragin. The amount of irrigation water was calculated using plant water requirement and the atmometer. At planting seeds were inoculated with bacterium strains. Biological yield, grain yield, harvest index and hundred grain weight was measured and determined. Results indicated that grain yield was different under stress and full irrigation conditions. In full irrigation condition maximum grain yield (458 g.m-2) and biological yield (870 g.m-2) were produced by Nitragin strain. Under stress conditions, the efficiency of strains was not different under mild and moderate stresses. Higher grain and biological yield obtained by Rizoking strain. Therefore, this strain had better adaptation to modrate drought stress condition, however in severe drought stress no difference among bacterium strains was observed.