JWSS - Journal of Water and Soil Science

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Limited time for crop residue decomposition and complete seedbed preparation in double-cropping necessitates reduced tillage which is associated with its shortcomings. Information about seedbed preparation aspects in double-cropping of wheat and mungbean in Isfahan is lacking. For this reason, the effects of various seedbed preparation methods on growth, seed yield and yield components of mungbean (experimental line 1-61-16) were studied in a wheat-mungbean double-cropping system during 1996 at the Agricultural Research Station, Isfahan University of Technology. Two residue management treatments (burned and nonburned) along with four tillage systems: moldboard plow, disk, khischee and no-till were laid out in a strip plot design within a randomized complete block design with four replications. Improved establishment and plant growth conditions associated with burning residue treatment significantly increased plant density, above ground plant weight, number of nodes per branch, plant height, number of pods per main stem and per square meter, number of seeds per pod on main stem and on branches, number of seeds per main stem, seed yield, biological yield and harvest index. Higher plant density in this treatment resulted in significant reduction in the number of branches and number of pods per branch. Desirable conditions for establishment and growth in disk and moldboard plow treatments significantly increased plant density, above ground plant weight, number of pods per main stem and per square meter, number of seeds per pod on main stem and on branches, number of seeds per main stem, seed yield, biological yield and harvest index. No-till treatment produced the least results in respect to the above traits. The results indicated that burning residues with disk tillage system might be an appropriate seedbed preparation method under conditions similar to this experiment.

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Obtaining high seed and oil yields of sunflower requires coincidence of vegetative and reproductive stages of growth of the plant with suitable environmental conditions via selecting appropriate planting date. Since the suitable date of planting for sunflower cultivars under Isfahan environmental conditions was not determined, this experiment was conducted in 1996 at the Agricultural Research Station, Isfahan University of Technology. In this study, five dates of planting (April 27, May 12 and 27 and June 12 and 29) and three open pollinated sunflower cultivars (Record, Vnimik 8931 and Armavirec) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered as the main plot and cultivars were randomized in the sub-plots.

Number of seeds per head (SH), l000-seed weight (SW), seed oil percent (SOP) and, consequently, yields of oil (OY) and seed (SY) were significantly reduced as planting was delayed. Reduction in these traits were considered to be related to the coincidence of vegetative and reproductive growth stages with higher temperatures prevailing at later plantings. Vnimik 8931 had higher SH and SW, and thus produced higher SY. This cultivar had lower SOP than Record, but produced higher OY than Record due to its higher SY. Armavirec was ranked the least for the measured traits, except for its SH that was slightly higher than that of Record. SH was the most contributing trait to the increase in SY, and SY was the most determining trait for the increase in OY. Date of planting by cultivar interactions for SH, SY and OY were significant. Nevertheless, the highest amount of the measured traits were obtained with Vnimik 8931 at the first planting date.

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Knowledge of the effects of row spacings and seeding rates on dual-purpose forage and seed production of an annual legume crop is essential for its proper agronomical exploitation. In this study, the effects of various row spacings and seeding rates on dry matter and seed yield in berseem clover (Trifolium alexandrinum L.) were evaluated in two consecutive years. The experimental design was a split-plot with four row spacings as main plot treatments in a randomized complete block design with four replications, and five seeding rates were allocated to subplots.

Combined analysis of variance of the two-year data showed that both row spacings and seeding rates influenced dry matter yield (DM), seed yield, plant height, 1000-seed weight and harvest index. Years, as well as two- and three-factor interactions did not affect the seed yield whereas row spacing × seeding rate, and year × seeding rate significantly affected the DM. The mean comparisons indicated that row spacings of 30 and 45 cm produced the highest DM of 3912.2 and 3900 kg/ha 45 and 60 cm spacings showed the highest seed yield of 1045.4 and 1093.3 kg/ha, respectively. 24 and 20 kg/ha seeding rates ranked the best in giving 1244.7 and 1223 kg/ha seed yield, respectively. The seeding rate of 16 kg/ha in the first year and 20 kg/ha in the second year produced the highest DM yield with means of 3837.5 and 3875.3 kg/ha, respectively. Regarding the dual-purpose of forage and seed production in berseem clover, 20 kg/ha seeding rate at 45 cm row spacing can be recommended for Isfahan region and for other comparable environmental conditions.

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It is believed that various types of field bean, including pinto, white and red, differ in adaptability to high temperatures and may, thus, differ in response to delay in planting. In order to evaluate this response, an experiment was conducted during 1996 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with split-plot layout. Main plots consisted of four planting dates (April 28, May 13 and 28 and June 13) and sub-plots included four genotypes of common bean (red bean, c.v. Naz pinto beans, experimental lines 11816 and 16157 and a white bean, experimental line 11805).

 Number of branches per plant, number of pods per branch and per unit area, number of seeds per pod of main stem and branch, number of seeds per main stem, per branch and per unit area, 100-seed weight and seed yield significantly reduced, while harvest index significantly increased by delay in planting and consequent increases in temperature and reduction in time for growth. The lower harvest index obtained with early planting was the result of the lower efficiency of the produced vegetative growth due to the coincidence of seed filling period with high temperatures. Pinto bean line 11816 ranked the highest for number of branches per plant and harvest index among the genotypes evaluated and produced the highest seed yield (3030 kg ha^-1). Although red bean Naz ranked the highest for number of pods and seed per main stem and per unit area, it had the lowest harvest index and 100-seed weight and, consequently, produced the least seed yield (2254 kg ha^-1). The results obtained indicate that delay in planting adversely affects bean seed yield. Pinto bean line 11816 may have higher yield potential among the genotypes studied at all planting dates under conditions similar to the present experiment. No specific relationship was observed between apparent seed characteristics and plant tolerance to heat.

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Flax (Linum usitatissimum L.), an oilseed crop, is widely adapted and grown in many regions of the world. Oil from regular flaxseed is used as an industrial drying oil because of the high level of linolenic acid (>50 %). However, the oils from new mutant genotypes of flax with a very low linolenic acid concentration (<2 %) are edible. Yellow seed colour can be used as a visual marker to distinguish edible-oil genotypes of flax from those of industrial type that are usually brown-seeded. In this study, different lines of flax with two seed colours (yellow and brown) in combination with two levels of linolenic acid (high and low) were evaluated in a randomized complete block design for agronomic traits, especially seed yield and its components. The results indicated that lines with high linolenic acid concentration had significantly higher seed yield than those with low linolenic acid. However, other characteristics including those of seed yield components were not siginficantly affected by linolenic acid concentration. Seed colour had a significant effect on number of seedling/m², basal branches, capsules per plant and seed yield per plant. Although seedling emergence was lower in yellow-seeded lines, they had more basal branches, capsules per plant and seed yield per plant. Higher seed yield per plant in yellow-seeded lines can be attributed to higher number of capsules per plant as a result of lower seedling emergence and plant density. Seed yield was not significantly different between brown and yellow-seeded lines. Thus, the effect of lower plant density in yellow-seeded lines was compensated by their higher basal branches and number of capsules per plant.

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Planting pattern through changing vegetative growth and utilization of environmental resourses affects yield components and seed yield. These effects were studied in the spring of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat, and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plants m^-2). The experiment was planted on March 13 using local safflower variety of Isfahan, named Koseh. Increase in row distance and plant density enhanced most developmental stages of safflower. Leaf area index was not significantly affected by row distance but increased as planting density increased. Up to the 50% flowering stage, 30 cm row distance produced highest plant dry weight, but had the least dry weight at the end of the growing season, probably due to the strong shedding of leaves. Up to the end of flowering stage, 50 plants m^-2 treatment produced the highest plant dry weight, but ranked lower as compared to 30 plants m^-2 treatment at the physiological maturity, probably due to the shedding of leaves. Row distance had no significant effect on number of branches per plant and per square meter, number of heads per branch, number of seeds per head, 1000-seed weight and harvest index. But number of heads per plant and per square meter as well as seed yield per plant and per square meter significantly decreased as planting distance increased. Plant density had no significant effect on number of branches per plant, number of heads per square meter, number of seeds per head, 1000-seed weight and seed yield. Increase in planting density increased number of branches per square meter, but reduced number of heads per branch and per plant, seed yield per plant and harvest index. The highest seed yield (4769 kg ha^-1) was obtained with 30 cm row distance and 40 plants m^-2 treatment. On average, 397 kg ha^-1 petal was harvested, which has a large economic value. However, petal clipping, over all treatments, reduced seed yield by about 7.4%. Considering the advantages of uniform distribution of plants and adaptation of safflower to flat planting, 30 cm row distance with 40 plants m^-2 might be appropriate for planting safflower under conditions similar to this experiment.

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Although safflower is known to be a cool-season crop, it is usually planted as a summer crop in Isfahan. Thus, an experiment was conducted in 2000 at the Agricultural Research Station, Isfahan University of Technology, to study the effects of date of planting on growth, yield components, and seed yield of safflower. Five planting dates (March 12, April 12, May 10, June 8, and July 12) and four safflower genotypes (Arak 2811, local variety Koseh, Nebraska 10, and Veramin 295) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered as the main plot and cultivars were randomized in sub-plots. Delay in planting from March 12 to may 10 reduced plant dry weight per unit area, number of heads per plant, number of seeds per head, seed yield per unit area, harvest index and petal yield. The above traits increased as planting was further delayed from May 10 to June 8. Highest seed oil and lowest seed protein contents were also obtained for this planting date. Plants of July 12 planting date did not reach physiological maturity. Among the genotypes evaluated and over planting dates, the highest and lowest number of heads per plant, 1000-seed weight, and seed yield were produced byArak 2811 and Veramin 295 (mean of the first and second planting dates), respectively. Highest seed yield (4512 kg ha

^-1) was produced by local variety Koseh in June 8 planting date. It might be concluded that this variety has adapted to the summer planting conditions of Isfahan by natural selection.

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To evaluate seed germination and seedling growth of safflower in moisture stress, germination of 15 genotypes at four water potential levels (ψ: 0, -0.4, -0.8 and –1.2 Mpa) was tested by Polyethylene glycol (PEG6000). Maximum germination (Gmax), germination rate index (GRI), time length to reach 50% germination (T₅₀), rootlet length (RL) and shootlet length (SL) were investigated. Effects of water potential levels and genotypes were significant for all the characteristics studied. Minimum water potential for germination was estimated between –1.17 and –1.59 Mpa in Goshkhani and LRV-51-51 genotypes, respectively. Different responses to moisture stress were found for rootlet length. In lower potential levels, seedlings had longer, weaker and thiner rootlets in comparison to the zero water potential (control). An increase in stress to –1.2 Mpa led to a severe reduction in rootlet elongation. All stress levels decreased GRI and SL, while potentials lower than –0.4 Mpa decreased Gmax. With a decrease in water potential from 0 to –0.8 Mpa, the T₅₀�stage was delayed three-fold compared to the control. Exotic genotypes had longer T₅₀ stage than Iranian genotypes. The highest GRI was related to three Iranian genotypes LRV-51-51, Varamin 295, and Isfahan local, and the lowest was related to CW-74 exotic genotype. Some of genotypes were evaluated for seed yield, oil yield and seed oil percentage under rainfed condition in 2004-05. The highest oil yield average belonged to two exotic genotypes PI- 537598 and Lesaf (326.4 and 313.9 Kg/ha, respectively) and the least was related to Zarqhan 279 Iranian genotype (133.2 Kg/ha). Negative and significant correlation was observed between seed oil percentage and GRI in the 0, -0.8 Mpa potential levels. According to the results, the existing genetic variation for germination parameters can be used for genetic improvement of seed early vigor in safflower.

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Canola (Brassica napus) is one of the important oil seed crops cultivated in many parts of Iran. One of the main problems of seed production of canola is pollination and fertilization of flowers. Insects are the major pollinators. In order to study the fauna of insect pollinators of 3 cultivars of canola including Talaye, Okapi and S.L.M. and the difference between the attractiveness of these cultivars to insects during the flowering period, insects were collected by sweeping net and identified. Their abundance was determined at different periods of time during a day. Results showed that insect pollinators belonged to five orders and 18 families. The most abundant pollinators were Hymenopterous insects specialy honey bees (Apis mellifera) which were about 50%. Irrespective of Apis mellifera, the most abundant insects captured belonged to Diptera. Three Dipterous insects, Bibio hortulanus, Metasyrphus corollae and Platypalpus sp. were collected and identified. During the flowering period (March to mid April) in Isfahan, honey bees were more abundant in the warmer hours of the day, mostly noon and afternoon, but were less active in the early hours of the day, morning, because of cold weather and low nectar production. Honey bees were more active than other pollinators on Talaye at 9 a.m. and on Okapi at mid-day, noon, and during afternoon. Results also showed that insect pollinators could increase seed yield by 53%.

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Sunflower (Helianthus annuus L.) can have an important role in vegetable oil production. Also, appropriate soil fertility is necessary to obtaine higher seed yield and quality of the crop. This experiment was conducted to investigate the effect of fertilizer treatments of macro and micronutrients on seed yield and other agronomic traits in sunflower. The effects of thirteen fertilizer treatemts (as main factor) were investigated on agronomoic traits of two hybrid cultivars, "HiSun33" and "Euroflor" (as sub factor) in a randomized complete block design with three replications. The results showed that there was significant interaction between fertilizer treatments and cultivars for most of the traits and the effects of fertilizer treatments were dependent on the cultivar. Almost all of the fertilizer treatments of N, P, K, Fe, Zn and Mn either significantly or non-significantly decreased the means of head diameter, 1000-seed weight, seed yield/plant, seed yield and oil yield in Euroflor cultivar however, in HiSun33 cultivar, each of N, P, and K fertilizers had no significant effect on seed yield. Application of Zn and Mn fertilizer in soil or spraying them on plants had no significant effect on seed yield and yield components in HiSun33 cultivar however, application of Fe feritilizer (Sequestrene) significantly increased the seed yield of this cultivar and had no significant effect on its seed oil. In HiSun33, seed yield and oil content for treatments of control, NPK and NPK+Fe were 4946, 5155 and 7090 kg/ha and 40.72, 43.10 and 43.07 %, respectively. The effects of fertilizer treatments on oil concentration of seed were not significant, thus the variation of oil yield was due to the seed yield. The correlation coefficients and regression analysis showed that seed weight and head diameter were most important seed yield components,. In general, it seems that in a soil conditions like that of this experiment, Fe fertilizer can increase seed and oil yield in HiSun33 cultivar.

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To determine the effects of different intensities of leaf removal at different reproduction stages of sunflower on seed yield and oil percentage, and the most sensitive stages to defoliation, an experiment was carried out by split-spilt plot design in randomized complete block with 3 replications at research farm, College of Agric. Urmia University, in 2004. The main factor, sub factor and sub-sub factor in our experiment were: 1. two cultivars, Uroflor and Alstar, 2. defoliation at four reproduction stages, star shape of inflorescence (R₂), pollination stage (R₅), seed setting initiation (R₆) and final period of seed setting (R₇), and 3. four defoliation intensities ( 0% as an undefoliated control, 25%, 50% and 75% ). Seeding was accomplished on May 23. Average triple factor interactions verified that different defoliations at R₂ stage have significantly reduced seed yield and oil percentage of both Uroflor and Alstar cultivars. Out of this reduction, 75 percent defoliation at R₂ was the most, while at R₅ and R₆ stages 50 and 75 defoliation caused significant reduction on seed yield in comparison with control. At R₇ stage different defoliations had no significant effect on seed yield of Uroflor cultivar, while, on Alstar cultivar, 75 percent defoliation at R₇ stage caused significant difference in relation to control. Also average triple interaction among factors showed that none of defoliation percentages had significant effect on oil percentage. In view of the fact that, seed development and filling occurred after defoliation at R₂ and R₅ , the most variation resulted from defoliation of valued traits like number of filled seed per head and weight of 1000 seeds, observed at R₂ and R₅ stages and consequently reduced seed and oil yields. On the bases of this experiment it could be concluded that sunflower cultivation with losses of 50 and 75 percent will be economically unprofitable and it will be more desirable to replace it with any other suitable crop in the region.

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Fescues (Festuca spp) are widely distributed in the temperate regions and are used for turf, forage and soil conservation. Though seed traits are important measures of the effects of endophytic fungi on their host, little information is available in this respect for Festuca. In this study, endophyte-infected (E⁺) and endophyte-free (E^-) clones of the six fescue genotypes were used to investigate the effects of endophyte on seed production. The relationships between seed traits plus direct and indirect effects of components on seed yield were also studied. Endophyte infection resulted in 38.1% to 249% more seed yields in some genotypes, though some were not affected by this symbiotic relationship. Correlations between traits and also results of stepwise regression were influenced by the presence of the symbiotic fungi. Path analysis showed that endophytic fungi changed direct and indirect effects of components on seed yield. In endophyte containing clones, panicle fertility had the most direct effects and number of panicle per plant and seed per panicle the most indirect effects on seed yield. In E- clones, panicle fertility had the highest indirect effects and other components had direct effects on seed yield. The results suggested that breeding strategies for increasing seed yield in fescue should consider the presence or absence of endophyte in germplasm.

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Thirty soybean cultivars from different maturity groups were evaluated in a randomized complete block design with four replications in Research Station of College of Agriculture at Tehran University in Karaj in 2004. The purpose was to determine genetic relationship of some important agronomic traits related to seed yield. Analysis of variance showed that there were significant differences among varieties for the traits under study, indicating the existence of genetic variation among varieties. Number of pods/plant, number of seeds/plant and 100-seed weight, all of which are considered yield components, had the highest genotypic correlation with seed yield. Using stepwise regression analysis, 85.6 % of seed yield variation was attributed to four traits, including harvest index, biological yield, protein precent and number of seeds /plant. Harvest index was more important for predicting seed yield compared to other traits based on standardized ßs. Results of path analysis showed that the harvest index and protein precentage had the highest and lowest direct and positive effect (p=0.536), (p=0.008), respectively. Therefore, harvest index may be considered as a selection criteria to improve seed yield in breeding programs. Results of factor analysis showed five independent factors accounted for 80.2 % of total variations in data. The first principle determined 28.2 % of total variation and was designated as phenologic factor.

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  Planting patterns through growth indices affect yield formation. To evaluate these effects on safflower, Koseh local variety of Isfahan, a field experiment was conducted in summer, 2004 at the Agricultural Research Station, Isfahan University of Technology. The experiment was performed using a randomized complete block design with a split plot layout and four replications. Main plots consisted of three row distances (20 and 30 cm flat and 45 cm on bed), and sub-plots included two planting densities (40 and 50 plant m^-2). The experiment was planted on June 25. The results showed that p lant canopy closed sooner, leaf area duration (LAD) increased and plant dry matter weight, leaf area index (LAI) and crop growth rate (CGR) were higher up to the middle of seed development as row distance decreased. In addition, the highest relative growth rate (RGR) and net assimilation rate (NAR) were obtained in 20 cm row distance. The highest (3039 kg ha^-1) and lowest (1930 kg ha^-1) seed yields were obtained with 20 and 40 cm row distances, respectively. Plant density did not affect the rate of canopy closure, CGR, RGR, NAR and seed yield. But, maximum plant dry weight, higher LAI and lower LAD values were obtained with 50 plants m^-2. The results obtained in this experiment indicate that 20 cm row distance with 50 plants m^-2 might be appropriate for summer planting of safflower, a local variety of Isfahan, under similar conditions.

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  During the past years, safflower genotypes have been selected from local variety of Isfahan, named Kouseh. The response of these genotypes to planting date might be different. To determine this, performances of several genotypes selected from Kouseh plus Arak 2811 ) as check ( were studied at the Agricultural Research Station, Isfahan University of Technology in 2002-2004. The experiment was conducted using a split-plot arrangement within a randomized complete block design with three replications. Planting dates were considered as the main plots and subplots consisted of 22 genotypes of safflower. Number of days from planting to emergence was highest (18.0 days) in early spring planting and lowest (10.3 days) in late spring planting. Days from planting to head visible, flowering and physiological maturity were decreased with delay in planting from autumn to late spring. Days from planting to emergence, head visible and physiological maturity were not influenced by genotype. Genotypes C116 and DP29 had the highest (145.0) and genotype ISF28 the lowest (140.2) days from planting to flowering. Plant height, number of first and second degree branches, number of heads per first and second degree branches, number of seeds per head, 1000-seed weight and seed weight per plant reduced significantly with delay in planting from autumn to late spring. Genotypes C128 and DP7 had the highest (120.0 and 120.5 cm, respectively) and genotype DP9 the lowest (104.2 cm) plant height. Genotypes DP6 and DP9 had the highest (12.8) and the lowest (6.7) first degree branches per plant, respectively. Arak-2811 had the highest (16.9) and genotypes DP9 and DP5 the lowest (7.2 and 7.1, respectively) second degree branches per plant. Number of heads per first degree branches was not significantly affected by genotype. Arak-2811 and genotype C114 had the highest (12.8 and 12.2, respectively) and genotype DP9 the lowest (5.1) number of heads per second degree branches. Genotype DP7 had the highest (45.9) and genotype C111 had the lowest (28.0) number of seeds per head. Genotypes DP3 and C128 had the highest (34.2 g) and lowest (22.0 g) 1000-seed weight, respectively. Genotype DP25 had the highest (20.5 g) and genotypes DP29 and DP9 the lowest (9.9 and 10.0 g) seed weight per plant. Harvest index was not affected by planting date and genotype. The result of this study showed that safflower may yield more in fall planting under conditions similar to this experiment. Genotype DP25 might be recommended for this planting date, genotypes ISF66 and DP25 for early spring planting and genotypes DP7 and ISF14 for summer planting.

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In order to determine the response of yield and seed yield components of red bean )Phaseolus vulgaris L. ( genotypes to delay in planting, this study was conducted in Factorial  experiment based on a RCB design with 3 replications in the Jahad-Keshavarzi Research farm of Miyaneh in 2006. Factors included cultivars in three levels(Naz, Gole and Sayad) and planting date in three levels (5 and 20 April, and 5 May). Results of variance analysis showed that the cultivars and planting dates had significant effects on all the characteristics. The interaction between cultivars and planting dates had significant effect on stem height, number of pod per plant, 100 seed weight, biological yield, grain yield and number of seed in pod. The Results of mean comparison indicated that SAYAD cultivar in the first planting date with 4033.3 kgha^-1 and Gole cultivar in the third planting date with 1500.2 kgha^-1 had the highest and lowest grain Yield, respectively. Total yield with all traits, except for the stem height, 100 seed weight and cultivar protein percentage showed a  positive and significant correlation.

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Rapeseed (Brassica napus L.) is one of the oilseed crops in the temperate regions and is adapted to different climate conditions. This crop can have an important role in production of vegetable oil, and providing appropriate soil fertility can increase its seed and oil yield. In order to investigate the effect of N, P, K, Fe, Zn and Mn on seed yield and other agronomic traits of rapeseed, an experiment was carried out at the Research Farm of Isfahan University of Technology in 2006. The experiment was arranged as split plot in a randomized complete block design with three replications in which eleven fertilizer treatments and two cultivars of rapeseed (Ocapi and Zarfam) were considered as the main and sub factors, respectively. The results showed that there was no significant effect of fertilizers on days to maturity, but application of NPK+Fe significantly increased the plant height in both cultivars. The fertilizer treatment had no significant effect on the number of pods per plant and seeds per pod. The interaction effects indicated that application of N, P, K, NP and NK significantly increased 1000-seed weight in Ocapi cultivar however NPK+Fe significantly decreased 1000-seed weight and non significantly increased seeds per pod in Zarfam cultivar. Application of N, NPK and NPK+Fe increased the seed yield by 13, 7 and 43%, respectively. Averaged over two cultivars, N significantly increased seed oil content, but significant interaction between fertilizers treatments and cultivars indicated that application of K and NP significantly reduced the seed oil content in Zarfam cultivar. Fertilizer treatments of N, NPK and NPK+Fe had higher effects on seed oil content and oil yield and means of these traits for fertilizer treatments of control, N, NPK and NPK+Fe were 39.7, 41.7, 39.4 and 39.8%, and 681.1, 816.4, 730.2 and 983.3 kg/ha, respectively which indicate that N and Fe increased the seed and oil yield in both cultivars. However, the application of Zn and Mn had no significant effect on seed yield and seed oil content. In this study, the variation of seed yield and oil yield was mainly due to the variation of number of pods per plant and seed yield, respectively. In conclusion, it seems that in soil and climatic conditions like this experiment, application of N and Fe can be economically important and increase the seed and oil yield in rapeseed.

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To study the effects of plant densities and planting orientation on the seed and forage yield of sorghum, an experiment was conducted at Hossein- Abad – Shahcal village –90 kilometers south of Bam-in 2002. The experiment was a factorial with randomized complete block deisgn and three replications. The treatments were: orientation with three levels (South-North, East – West, Northeast – Southwest) and plant densities with four levels (50000, 70000, 90000, 110000 plants per hectare). Results of analysis of variance showed that planting orientation had significant effects on seed yield, weight of 1000 seeds, number of tillers, dry matter yield, length and diameter of shoot. Mean comparisons, showed that the maximum and minimum amount of the above mentioned traits except for shoot length was obtained under the North-South and East-West orientations, respectively. Significant differences were also found among densities in terms of all the mentioned traits. Results showed that increasing density decreased seed yield, weight of 1000 seeds, number of tillers and shoot diameter. The highest and lowest values (except of seed yield) were recorded for 50000 and 110000 plants/per hectare, respectively. Dry matter yield and the shoot length increased with increasing density. Based on the results of this experiment, the best plant densities to obtain the highest forage and seed yield are 70000 and 110000 plant per hectare, respectively and the best planting orientation is North-South.

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This study was conducted to investigate the effects of thirteen fertilizer treatments (as main factor) on agronomic traits of two local cultivars (as sub factors) of sesame (Sesamum indicum L.), "Mobarakeh" and "Ardestan" in Isfahan by using a randomized complete block design with three replications. The results showed that applying fertilizer treatments of N, P, K, Fe, Zn and Mn had no significant effects on yield components, seed yield and oil yield. However, comparing the control treatment, simultaneous application of all fertilizers significantly reduced days to maturity. Significant interaction between cultivars and fertilizer treatments was observed for seed oil content, as application of N, P, NPK and NPK+Fe+Zn in Mobarakeh and application of N+K in Ardestan reduced seed oil content. However, the other fertilizer treatments had no significant effects on this trait. The Mobarakeh cultivar compared to Ardestan had significantly higher plant height, higher seeds per capsule, lower 1000-seed weight, higher seed yield per plant and per hectare and higher oil yield. Seed yield for Mobarakeh and Ardestan cultivars were 1646 and 1169 kg/ha and their seed oil contents were 52.88% and 53.81%, respectively. The correlation coefficients and regression analysis showed that the variation of seed yield was mostly due to the number of capsules per plant and seeds per capsules, thus these two traits were the most important yield components. Oil yield had a very high correlation coefficient with seed yield (r=0.99^**), whereas its correlation with seed oil content was very low (r = -0.10^ns). Therefore, it seems that seed yield was the main cause of higher oil yield.

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Safflower (Carthamus tinctoius L.) is an Iranian native crop that is adapted to different environmental conditions of this country. Sixteen safflower varieties/lines were spring-planted in 6 research stations including Sararood (Kermanshah), Maragheh, Ghamlo (Kordestan), Khodabandeh (Zanjan), Shirvan (North Khorasan)and Khohdasht (Lorestan) with and without drought stress conditions each in a RCBD with 3 replications. Some drought resistante indices including Mean of Productivity (MP), Geometric Mean of Productivity (GMP), Tolerance (TOL), Stress Tolerance Index (STI), Stress Susceptibility Index (SSI) for seed yield and genotypes Cell Membrane Stability (CMS) were calculated. Results showed that STI was the most appropriate index to identify drough resistant genotypes. Estimation of STI from mean of all stations revealed that Gila, CW-4440 and PI-537598 with high STI showed high seed yield in both stress and non-stress conditions. Caculation of STI standard deviation for these genotypes showed that Gila had less STI stability over the locations than other two genotypes so, CW-4440 and PI-537598 are more stable in drought stress resistance. Analysis of variance for cell membrane stability (CMS) of genotypes showed the significant differences in 1% level of probability between genotypes. S-541 had the highest and Kino-76 had the lowest CMS. There were significant and strong correlations between STI, MP and GMP with CMS namely, genotypes with more stable membrane having more drought resistance in field condition. So, cell membrance stability can be a useful and fast method to screen germplasm and identify drought resistant genotypes. Cluster analysis based on STI,MP,GMP, CMS and seed yield in both stress and non-stress conditions divided genotypes into 3 groupes. Results of clustering also identified S-541, Gila, CW-4440 and PI-537598 as 4 superior genotypes and confirmed the results of other methods.