نشریه به زراعی نهال و بذر
سال سی و یکم شماره 2 (1394)

To assess the yield and agronomic traits of snapbean cultivars in different planting times and methods, an experiment was conducted for two years in Zarghan using a split- split plot with three replications. The main plots were two snapbean cultivars, Sunray and Contender, subplots were three planting times, end of April, early in May and mid May, when temperature was 24.7, 26.9 and 25.2ºC, respectively and sub-sub plots were three planting methods and seeding distance on row, 10cm single row, 15 and 20 cm double cross-rows. Different agronomic traits and yield in different treatments were recorded in different growth stages. Analysis of variance on data showed that the effects of planting methods and seeding distance on row were not significant on yield, but the effects of cultivar and planting time were significant. Seed germination and seedling emergence in Sunray cultivar occurred earlier than in Cantender cultivar. Sunray cultivar with 43.02 tha-1 in the first year and 57.57 tha-1 in the second year, produced higher yield compared to Contender cultivar with 24.34 tha-1 yield in the first year and 39.08 tha-1 in the second year. Two years mean yield of Sunray (50.29 tha-1) was also higher than that of Cantender (31.71 tha-1). The first planting time (end of April) increased yield of both cultivars and there were significant differences among planting dates for yield and agronomic traits. Generally, Sunray cultivar with higher yield and better bean quality, and planting time of end April were recognized as the best treatments for Zarghan areas.

For evaluation and determination of genetic capacity of existing apricot genotypes in Iran, an experiment was performed in RCB design with seven treatments and three replications on August 2004 in Sahand Horticultural Research Station. Selected promising genotypes with numbers of 177, 190, 390, 414, 416, 464 and 269 were compared with Ordubad 90 cv. (as control) for a period of seven years. The results demonstrated that there was no significant difference between yielding and full blooming dates of the genotypes and control. The range of fruit maturation between the most early and the most late maturity genotypes was 45 days. Genotype 414 had the maximum fruit weight (57.6g) and the highest fruit to stone weight ratio (30.3). From the viewpoint of fruit flesh thickness, the lowest difference was observed between control and genotype 464, and the highest significant difference was detected between control and genotype 269 (p≤0.05). Despite relative height of stigma to anthers in genotypes 269, 414, 464 and 177, no problem was observed in fruit setting of them. Based on the biochemical traits results, the highest significant differences were observed between TSS value of genotypes 416 and 177 with 7.7% and also between total organic acids content of genotypes 390 and 177 with 1.2% (p≤0.05). Difference between fruit active acidity (pH) of genotypes was not significant. There was also a negative and significant correlation (r2 = 0.8) between total organic acids content and pH of the genotypes fruit. Based on all results, genotype 177 was recognized for fresh consumption, genotypes 464 and 390 for processing and genotypes 190, 414 and 269 for dual.

In order to study the effects of sub-zero temperatures on advanced chickpea genotypes, this study was carried out as split-split plot based on randomized complete block design with three replications under controlled conditions (cold room) at Maragheh Dryland Agricultural Research Station during 2013-2014 cropping season. Different seedling stages (1,3 and 6 weeks after planting) were in main plots, different sub-zero temperatures (0, -5, -10, -15 and -20 °C) in sub plots and chickpea genotypes (ILC3279, FLIP00-75, ILC482, FLIP00-84, Sel.96th.11439, ILC 533 and cultivar Saral) in sub-sub plots. Results showed that seedling age did not significantly affect the frost resistance ratio (FRR), but the highest and the lowest FRR were observed in seedlings with 3 and 6 weeks age, respectively. Cold severity had significant effect (p≤ 0.01) on FRR and with increasing cold severity from 0 to -20°C, FRR of genotypes was decreased. Differences among chickpea genotypes were significant (p≤ 0.01) and Saral cultivar with FRR = 0.89 showed an acceptable level of cold tolerance comparing with the other genotypes.

In order to study the effects of mineral and biological compounds as thinning agents on fruit quantitative and qualitative characteristics of apple cv. Red Delicious and to compare them with flower and fruit-hand thinning, a research was carried out in a commercial orchard in Semirom, Iran. Treatments included lime-sulfur (6%, 8% and double application of 6% first at 30-40 and then 70-80 bolting percentage), ammonium thiosulfate (20, 25 and twice application of 20 mll-1 (in 30-40 and 70-80 bolting percentage) and prohexadione- calcium, Apogee® (300, 450 and twice application of 300 mgl-1 (first at 70-80 bolting percentage and then 2-3 weeks after FB), and hand-thinning of flowers (at full bloom) and fruits (at 4 week after FB),which were applied on selected trees. The results showed that all of the treatments except Apogee (300 and 450 mgl-1) significantly thinned the fruits and reduced fruit set (10 -50 %). The treatments increased fruit weight(51%), volume(48%), total soluble solids (23%), TSS/total acid ratio(38%) and color and enhanced leaf area index (30%). There were no significant difference between control and the total acidity of fruits. Twice application of 20 ml ammonium thiosulfate was the best economically treatment. In terms of yield and yield efficiency(TCSA), treatments were significantly different, so that the control and lime sulfur 8% had the highest and lowest yield, respectively.

To evaluate the effect of training from on strength of branches of Thomson prange on poncirus rootstock, an experiment was conducted in Astara Citrus Station during 2008-2014, using factorial on the basis of randomized complete block design with five replications. The first factor was crotch angle (45, 65 degree and check) and number of branches (3, 4 and 5) was considered as the second factor. In the first two years, budding plants were produced and during the growth of buddingplants in the third year, treatments were applied. Trees were transplanted to the land according to the planting plan at the end of the third year. Heavy snow in February 2013 broke many of the branches in all treatment so that the perfect analysis of data could not be done according to the plan. However, analysis by chi-square method showed only significant correlation between the number of bloken branches and up trunk diameter of crotch. No correlation was detected between number of broken nranches and number of branch and crotch angle. Correlation between broken branches due to heavy snow, crotch angle and branch number was not also observed pulling of remaining limbs showed significant difference between maximum stresses at breaking and crotch angle. Branches with 65 degree crotch angle could handle more pressure than those with 45 degree crotch angle.

Fire blight disease caused by Erwinia amylovora is the most important and serious biotic stress on pear worldwide and in Iran, therefore its control in infected areas is important economically. Science the common methods of disease control are inefficient in control of fire blight, other ways should be investigated to overcome the disease. The present study was carried out to find an efficient way of control based on supporting plant tissues and reducing growth of shoots by application of edentate managenesium sulfate and salicylic acid. In this study which was carried out in Qazvin during 2012 and 2013, the effects of different concentrations of manageseium sulfate and salicylic acid an disease incidence and bacterial population were investigated on pear cv. Louis Bonne in an infected orchard and in laboratory. The results showed that effects of different concentrations of mineral compound and their combinations on disease development and shoot growth were significantly different compared to the check treatments in both years. Increasing the concentration of mangenesium sulfate from 0.5 to 0.7 g/1000 had a positive effect on disease reduction but increase of the concentration of Salicylic acid from 0.1 to 0.5 g/1000 had a negative effect on disease reduction. The results also indicated that if the effects of nutrients such as managenesium sulfate are supported by the effects of Salicylic acid in shoot growth inhibition, a better disease control will be achieved.