جستجوی مقالات مرتبط با کلیدواژه "فصل کاشت" در نشریات گروه "زراعت"

Planting date and genotype are two important factors affecting the growth and yield of crops, including chickpea.Therefore,In order to investigate the possibility of winter chickpea grown under dryland conditions in comparison with conventional farming (spring) and to determine the appropriate figures in each of the seasons of planting, research was conducted in the agricultural year 2008-2009 in Aleshta.Experiment two sowing seasons (winter and spring) and Varieties (Azzad, Arman, Hashem and local mass Greet) that the factorial in a randomized complete block design with four replications.The results showed the effect of planting season, grain yield, number of pods per plant, number of seeds per plant, number of seeds per pod, one seed and two seed pods per unit area, number of pods per plant and seed weight were significant. Fall planting 1819.8 kg per hectare in grain yield, number of pods per unit area 669.3 pods per square meter and the number of seeds per square meter(675) increased. The different varieties significant effect on grain yield, number of seeds per pod, pod and seed weight per unit area had a single seed.The highest grain yield (2243.3kg ha) related to the cultivation of winter and Azad varity.Due to a significant increase in crop yield of winter to spring and good product positioning also recommend This product Aleshtar dry conditions in winter and Azad varieties resistant to blight disease is to be planted.

Sowing date is an important determinant of yield in canola. Cultivation of winter rapeseed cultivars in semi arid regions of Iran however it has high potential for production، but، mentioned cultivars are late maturity and this late maturity cause to that silique formation and seed filling periods mature in the same time with hot and dry weather condition. In contrast، spring rapeseed cultivars are shorter growth duration and in this regard، identification of spring rapeseed cultivars with high cold tolerance for autumn planting cause to early harvest. In order to investigation of spring rapeseed cultivars reaction to spring and autumn planting dates، an experimental was carried out in a split plot design based on RCBD with four replications for two years (2004-2006) in Karaj. Treatments were included planting season in two levels as main plots such as common planting date، autumn planting (27 September) and spring planting (25 March) and spring rapeseed varieties as sub plots in 24 levels. The results indicated that simple effects of planting season and variety and also interaction effect on silique per plant، seed per silique، 1000 seed weight، seed yield، oil yield، biologic yield and harvest index were significant at 1% level probability. In autumn planting، Hyola 401 with greatest 1000 seed weight and high seed per silique had the highest seed yield (4689 kg. ha-1) and Hyola 330 produced the maximum oil yield (2165 kg. ha-1)، wherease RG 405/03 had the maximum seed yield and oil yield (2066 and 713. 6 kg. ha-1، respectively) in spring planting. On the basis of this result، some of spring rapeseed cultivars with high cold tolerance and high potential such as Hyola 401 could be planting in early autumn at moderate cold regions of Iran like Karaj.

In order to study the effects of planting date and plant density on yield and its components in three chickpea (Cicer arietinum L.) cultivars in rainfed conditions of Ilam، a field experiment was carried out using split plot design as factorial by complete randomized block design with three replications at Shirvan-Chardavol Agriculture Research Station during 2008-2009. Sowing dates were assigned to main plots at two seasons planting (autumn and spring)، plant density (20 and 40 plants/m2) and three cultivars (Arman، Hashem and Azad) were arranged as randomized in sub-plots. Results indicated that grain yield and yield components were affected by planting date and autumn planting produced the highest grain yield (1578 kg/ha). Number of pods per plant، grain yield، 100-grain weight and harvest index were affected by planting density. The highest grain yield obtained from plant density of 20 plants/m2. In this experiment، all traits were affected by cultivars and Azad cultivar showed the highest grain yield and its components. Interaction effects of planting date × plant density × cultivars had a significant effect on grain yield. The highest grain yield (1940kg/ha) obtained from Azad cultivar in autumn sowing date at the rate of 20 plant/m2. Using soil and environmental factors in autumn planting of Azad cultivar resulted in produce of maximum yield and yield components. Complementary researches were recommended for achieving applied results.

Evaluation of weed population and their interference on lentil varieties at different sowing date was investigated in a field experiment in Khorramabad during 2005-06 growing season. The experimental design was a randomized complete block in factorial arrangement with 4 replications. The experiment had 3 factors including: planting date at three levels (autumn, winter, and spring) weed interference at two levels (weed free, and weed infested throughout the total growing season), and three lentil varieties (Gachsaran, Flip93-93, and Lorestan landrace). Broad leaf weed species relative frequency for autumn lentil was more than winter and spring lentil 77.8 and 345.7% respectively. The highest level of relative frequency, and importance value in all sowing dates was belonged to safflower (Carthamus oxyacantha) and bedstraw (Galium tricornutum). Weed population severely decreased as sowing date delayed, so that average weed density for winter and spring lentil was only 40.5 and 4.3% of weed density in autumn lentil. There were not significant differences between autumn and winter lentil from the viewpoint of weed biomass. Spring lentil weed biomass was lower than 1/5 averaged over winter and autumn lentil. In autumn and winter lentil weed interference caused yield loss by 32.6 and 33.5% respectively. Yield loss due to weed interference for spring crop (22.3%) was significantly lower than for two other sowing dates. Lentil variety effect and its interaction with sowing date on weed population characteristrices were not significant.

To study the effects of sowing dates on seed germination and on seed vigor of 12 spring rapeseed cultivars, an experiment was performed in years 2005-2006. During the first year, 12 cultivars of spring rapeseed were planted in the Research Field of Seed and Plant Improvement Institute, Karaj, Iran. During the second year, standard germination test was conducted to study the performance of the seeds grown during the first year of the experiment. A factorial experiment in randomized complete block design was employed. According to the results, the seeds grown during the two seasons were significantly different from the view point of seed weight, germination, length of radicle and plumule, seedling vigor index, number of normal and abnormal seedlings, mean daily germination as well as daily germination index. In addition, the effect of cultivar was significant on seed weight, germination, length of radicle, plumule and seedlings, seedling vigor index, number of normal and abnormal seedling, mean daily germination as well as daily germination index. The seeds of autumnal cultivation were better off from the view point of seedling vigor as well as other important characteristics of seed vigor. Among the cultivars, RG405/02 was better than the others due to its high seed weight. A reduction of seed weight during germination could be used as a valuable index to determine seed vigor.

In order to determine optimum seed density and sowing time of lentil (Lens culinaris Medik) in Northern Khorasan, this study was conducted in Shirvan field experiment station in Northern Khorasan in 2002-2004 growing seasons. There were four seed density levels: 50, 100, 200 and 400 seed/m2, and two sowing seasons: Winter (Entezary) and spring, arranged in a factorial experiment in randomized complete block design with three replications. During growing season, agronomic traits such as flowering date, plant height and physiological maturity date were recorded. After harvesting, 100 grain-weight and grain yield were measured and recorded. Results of combined analysis of variance indicated that there was significant differences between the grain yield of the crop in spring and winter (entezary) seasons. The highest grain yield belonged to 200 seed per m2 in Entezary sowing time (812 Kg/ha), that was a significantly different in comparison to the other treatments. These results recommend that in dryland conditions of Northern Khorasan lentil are to be grown as Entezary crop with 200 seed per m2.

In order to study effects of plant density on water use efficiency (WUE) in spring and summer growing seasons in Esfahan region, five safflower genotypes including two selected lines from Esfahan landraces and three improved cultivars (Arak 2811, Gilla and Kooseh) were compared in two growing season (sown on April. 4 and July. 6) and three plant densities (40, 20 and 13 plants per m2) using split-split plots experimental design in Isfahan in 2000. The results showed that differences in water use efficiency between two growing season was significant (P<0.01). Water use efficiency in summer growing season better than spring growing season by 17%. Summer growing season produced 474.6 kg/ha less grain yield than spring growing season, however, WUE in summer growing season was higher than spring growing season. Plant density effects were also significant on water use efficiency. The highest and the lowest of WUE were 0.481 kg/m3 and 0.308 kg/m3 40 and 13 plants per m2, respectively. The main factor that contributed to higher WUE was higher plant in density which increased grain yield. Arak 2811 in spring growing season and line 1 in summer growing season had the highest WUE