نشریه گیاهان دانه روغنی
شماره 1 (1395)

In order to find the best planting pattern of soybean (Glycine max L. Merill) with sorghum (Sorghum bicolor L.) intercropping for utilizing environmental parameters to obtain high yield, this research was performed in Gorgan and Ali Abad. The experiment consisted of three levels i.e. pure soybean with density of 400000 plants per hectare, intercropping of sorghum and soybean with density of 250000 and 400000 plants per hectare, respectively and intercropping of sorghum and soybean with density of 300000 and 480000 plants per hectare, respectively. Each treatment was comprised of sixty 66.66 - meter long rows. Row distance was 50 centimeters. For measuring plant height, number of tillers, stem diameter and number of nodes, 10-randomly selected plants within a quadrat were harvested. In addition, total surface area was recorded based on research and extension project protocol. Analysis of the data was performed using t-test. The results revealed that the fresh forage yield with intercropping at 300000 and 480000 plant density for sorghum and soybean, respectively were 33.33 and 34.32 percent superior in Gorgan and Aliabad, respectively compared to the check treatment (pure sorghum with the density of 250000 plants per hectare). Mean comparison of dry forage also indicated 24.01 and 26.12 % increase in Gorgan and Ali Abad, respectively.

To study the effects of planting date and plant density on phonological, and morphological characteristics, as well as yield components and seed yield of soybean (Glycine max L. Merill), a field experiment was conducted in a split plot arranged in a randomized complete block design with three replications at the Agricultural Research Station of Gorgan (former Iraqi Mohaleh) in 2011. Four planting dates (28 May, 12 June, 27 June and 12 July) were the main plots, and four plant densities (21, 28, 35 and 42 plants per square meter) with planting patterns of (30 × 8, 35 × 8, 45 × 8 and 60 × 8 cm) were sub-plots. The results of analysis of variance showed a significant effect of planting date on days to flowering, days to maturity, number of nodes on the main stem, plant height, number of pods per main stem, seed weight and seed yield. Mean comparison using DMRT revealed that the highest and lowest number of days from planting to maturity were obtained at the first and fourth planting dates, respectively. Mean comparison also showed that maximum yield (4325 kg ha-1) was produced at 28 May planting date with plant density of 28 plants m-2. It might be concluded that the cultivar studied in this experiment could produce highest yield using favorable environmental conditions when planted on 28 May with planting density of 28 plants m-2 .

Nowadays crisis of water is one of the most important challenges in the world and Iran. Developing cultivars tolerant to drought stress should be one of the research priorities in agriculture sector. To evaluate the effect of drought stress on morphological traits and seed yield of soybean cultivars, a pot experiment was carried out as a factorial in a Randomized Complete Block Design with three replications in Gorgan in 2014. The cultivars consisted of Williams, Sahar, Gorgan3 and Katul and the treatments were the check (full irrigation), the stop of irrigation at vegetative growth stage, flowering, podding and seed filling. Planting was summer sown. Plant height and the other traits were recorded at physiological maturity and the seed yield of each plant was determined after harvesting. The results showed that the drought stress decreased seed yield, number of nodes, plant height, and the weight and length of root. The highest and lowest plant height and number of nodes belonged to G3 and Williams. Sahar and Williams produced the highest and lowest number of pods, respectively. Katul and Williams produced the highest (11.5333 g plant-1) and lowest (8.7333 g plant-1) plant seed yield, respectively. Based on the results of traits mean and seed yield, as a whole Katul and Sahar had higher tolerance to drought stress compared to two other cultivars.

In order to study the effect of vermicompost fertilizer and planting pattern on yield of two cotton cultivars, an experiment was carried out, as split factorial in a randomized complete block design with four replications in Ali Abad in 2013. The treatments consisted of vermicompost as the main plot at four levels (control (without vermicompost), two tons per hectare, four tons per hectare and six tons per hectare) and the sub-plot were combination of two cultivars vz. Sahel and Golestan and planting pattern at two levels (Rectangular and Parallel pattern). The results showed that the interaction of vermicompost × planting pattern × cultivar had no significant effect on number of bolls per plant, fiber weight per plant, the total weight of seeds per plant, first and second yield, 100-seed weight, boll weight, percentage of lint and seed cotton yield. The simple effect of vermicompost on first picking, total fiber weight, total seed weight per plant at four ton ha-1 vermicompost application were two ton ha-1, 46.36 and 90.94 gr plant-1 , respectively and in the control with 1.519 and 1.608 ton ha-1 and 15.74 and 37.47 gr plant-1 was the lowest. Mean comparison showed that Golestan cultivar was superior to Sahel for first picking, total fiber weight and seed yield.

This research was conducted to identify the most tolerant new sunflower hybrids to drought stress and to evaluate drought stress effect on yield and yield components, using RCBD with three replications under normal irrigation and elimination of irrigation from flowering stage onward at Islam Abad-e- Gharb Research Station during 2014-2015 growing season. In this study, 11 new sunflower hybrids were evaluated. The results showed that drought stress significantly decreased grain yield, plant height, head diameter, 1000-seed weight, seed per head and days to physiological maturity. Among evaluated traits, grain yield followed by 1000-seed weight and seeds per head were affected more than other traits by drought stress. RF81-131/1*AF81-222 produced the highest grain yield under normal condition with 5815 kgha-1 followed by Barzegar and Hysun33 with 5513 and 4922 kg ha-1, respectively. Under drought stress, RF81-131/1*AF81-222, Azargol, Hysun33 and Barzegar had the highest grain yield with 4201, 3750, 3554 and 3524 kg ha-1, respectively. Based on the results, RF81-131/1*AF81-222, Barzegar and Hysun33 were suitable for both normal and drought stress conditions, hence it could be recommended to farmers and Azargol was one of the suitable hybrids for drought stress conditions.

Nowadays, cotton as a second crop following rape (Brassica napus L.) in Golestan province is one of the appropriate methods to insert cotton in crop rotation. Hence, it seems necessary for weed control (volunteer rapes, in particular), and as a result to prevent qualitative and quantitative reduction of seed cotton yield. This study was conducted as a factorial in a randomized complete block design with two factors (cultivar and weed control method) and four replications. Cultivars were Armaghan, Golestan and Sepid. Weed control program consisted of two hand weeding and application of herbicides (Envoke, Convey, Treflan and Dioran). Based on the results, Golestan had the highest yield indicating its superiority as a second crop after canola to other cultivars. Among herbicides used, the highest control percent of volunteer rape was observed with Envoke treatment at 0.95 percent. Comparison among herbicides revealed that Envoke herbicide had significant difference for total lint yield (1289 kg/ha) with Convey (1155 kg/ha), Dioran (1159 kg/ha) and Treflan (1081 kg/ha). Therefore, planting Golestan cultivar and in addition application of Envoke, Dioran and Convey instead of Treflan as a herbicide in cotton double-cropping following rape is recommended.

Macrophomina phaseolina attacks many crop species including safflower and it causes charcoal rot. To investigate the pathogenicity of four M. phaseolina isolates (M0, M2, M5 and M6) on four safflower genotypes (Acetria, LRV5151, Arak 2811 and 34074), this study was performed at the Agricultural Sciences and Natural Resources University of Gorgan. The length of spots caused by fungi isolates inoculated in the lower part of plant stem was measured. This experiment was performed in an unbalanced completely randomized design under field conditions. The results of analysis of variance showed a significant difference between the isolates at 1% probability level. The interaction of genotype × isolates was significant at the 1% level. In this study, isolate of M2 with a maximum length of spots on all four safflower genotypes was identified as the most virulent isolate and M0 with the least length of spot was the least virulent isolate. Among the genotypes, genotype Acetria to two isolates of M0 and M6, genotype LRV5151 to two isolates of M0 and M5 and genotype 34074 to two isolates of M5 and M6 showed more resistance. None of the genotypes was resistant to isolate M2 and all genotypes were susceptible to this isolate.