نشریه تولیدات گیاهی
سال سی و دوم شماره 1 (تابستان 1388)

Drying method has an important role on medicinal plants production and affect quality of derived drugs. In order to study the different drying methods on some Achillea species, an experiment was conducted in factorial randomized based on complete block design (RCBD) with tow factors: Achillea species (5 species) and drying methods (5 methods) with three replications. The first factor was Achillea millefolium, A. eriophora, A. nobilis, A. biebersteinii, A. wilhelmsii and the second factor 1- drying under sun for 72 hours 2- drying in shade 25°C for 120 hours 3- drying in 50°C for 48 horse 4- drying in 100°C for 24 hours 5- drying by microwave for less than 10 minutes. Essential oil was extracted from fresh sample and compared with these methods. The results showed significant difference (p<0.01) between species and drying methods on weight loss, final water content and essential oil percentage. Result also showed significant interaction between drying methods and species (p<0.01). Highest percentage of essential oil was obtained from A. eriophora and lowest percentage obtained from A.wilhelmsii. Highest percentage of essential oil was attained from drying method at 25°C and the lowest amount in drying at 100°C. In conclusion, drying of Achillea in 25°C was the best method for essential oil content and quality.

A factorial experiment was conducted at the Agricultural Research Station of Bahonar University of Kerman to study the effects of salinity on the growth and yield of two maize cultivars in 2006. The design employed was a completely randomized design with three replications. Treatments were a combination of all levels of two factors including hybrid (single cross 647, three way cross 647) and electrical conductivity of soil solution (4, 6, 8, 10 dS/m). The results showed that the measured traits (shoot length, number of leaf, leaf area, dry weight and chlorophyll content) were affected significantly by salinity. The highest and lowest amounts of mentioned traits belonged to control and 10 dS/m treatments, respectively. Data analysis of variance also showed that the number of row per head, number of grain per row, the total number of grain per head and thousand grain weights were affected very significantly by salinity. Mean comparisons using Duncan multiple range test showed that control produced the higher amount of mentioned traits while severe stress produced the lowest. Yield production was reduced very significantly by salinity. Harvesting index was also affected by salinity. The effect of cultivars on most of the traits was not significant. Interaction effects did not influence any of the vegetative and reproductive traits significantly either.

Presence of genotype × environment (GE) interaction necessitates evaluations in a wide range of environments to find desirable genotypes. This study was carried out to determine the stability of grain yield of 21 chickpea genotypes, in RCBD with three replications under rainfed and irrigated conditions in College of Agriculture, Razi University of Kermanshah, Iran, for 4 years. The genotype × environment interaction effects were analyzed using the additive main effects, and multiplicative interaction (AMMI) statistical model indicated that it was significant at 1% level of probability. The sum of squares of G × E interaction was partitioned by AMMI model into four significant interaction principal component axes (IPCA). The first two principal component axes (IPCA1 and IPCA2) in total contributed to 66.58% of total genotype by environment interaction. A biplot generated using genotypic and environmental scores of the first two AMMI components also showed that genotypes 15 (FLIP 92-104 C), 8 (FLIP 92-9 C), 7 (FLIP 92-47 C), 1 (FLIP 92-31 C), 16 (FLIP 92-158 C) and 21 (ILC 482) were also selected as stable genotypes, while the genotypes 7, 8, 16 and 21 were outstanding for high yield and stability.

According to some observations, west of Iran is part of pear origin center. Topographical and geographical situations of Kurdistan province lead to plants variation. There are different pear varieties in this area such as wild pear genotype. The aim of this study was to investigate and characterize the native type of pear varieties in west and central part of Kurdistan province. To identify of pear genotypes, 58 phenotypic traits of flower, fruit, leaf and branches were selected. Measurements were carried out during the bud growth to leaf abscission period in two successive growth seasons. In this study, 416 pear trees were grouped in 28 varieties, and the mean of 20 data were analyzed for each trait. According to the results, 28 varieties were determined and the relationship between them was calculated. the first component had 84.62% of the total variance. Principle component analysis had a fairly good agreement with cluster analysis. Our results related to some flowers and fruit traits differed from previously reported ones.

Delaying sowing cultivation of canola was cased by Khouzestan rotation condition. In order to reduce comprehensive cultivation delay injury, this study was carried out in Shavoor Agricultural Research Station during 2004-2006 in randomized complete block design (RCBD) in split plot method with 4 planting dates 11th Nov, 21th Nov, 1th Dec, and 11th Dec in main plots and five nitrogen levels, 0, 50, 100, 150 and 200 kg/ha in sub plots with 3 replications. The results of the component analysis showed delay in planting from 11th Nov to 11th Dec reduced 24.6 pods per plant, 3.1 seed per pod, 0.43gr thousands seed weight, 1084.8 kg/ha seed yield, 5.6 seed oil percent and 539.1 kg/ha oil yield. There was significant difference between nitrogen levels application increasing form 0 to 200 kg N/ha to increase 55.3 pods per plant, 2.1 seed per pods, 0.6 gr thousands seed weight, 1965.7 kg/ha seed yield, 3.5 seed oil percent and 789.0 kg/ha oil yeild. Interaction effects showed that yield and yield component increased significantly by increasing of nitrogen levels for each planting date. Because there was no significant difference between 150 and 200 kg N/ha, 150 and 200 kg N/ha for normal and late planting date were recommended respectively.

In order to study the effect of crop residue management (C.R.M) and nitrogen splitting (N-splitting) methods on yield and yield components of canola, a filed experiment was conducted in Research Station of Shahid Chamran University in 2005-2006, 2006- 2007 (first year wheat, second year canola). The experiment was set up in a split plot design with three replications. The main plot treatments were C.R.M (i.e. incorporation, removal and burning the wheat residue) and sub plot treatments were N-splitting with combination of nitrogen- based and top dressing of nitrogen applied at three levels (i.e. 50+50, 25+75 and 25+50+25 %). The measurement of plant characteristics, plant density and sum of dry matter of weeds were used to evaluate plant growth and standing within canola population. The results indicated that weed plants greatly declined regardless of type of weed species, when the plant residues were incorporated into the soil. Further reduction could significantly inhibit weed growth and nitrogen source applied in form of N-splitting (50+50%). Findings also showed that the highest (19.4 plant/m2) and lowest (5.1 plant/m2) weed plants were observed under burning the residues treatment receiving 25+75 % N- splitting and incorporation of the residue treatment receiving 25+50+25 % N- splitting respectively. The highest (153.8 g/m2) and lowest (43.2 g/m2) yield production of dry matter of weed populations were accumulated when the residues were burned and received 25+75 % N- splitting incorporated and receiving 25+50+25 % N- splitting respectively. in the present study, the evidence indicated a desirable method of crop residue management when incorporating the residues in form of N- splitting (50+50 %).

Application of gibberellic acid (GA3) increases the rate of vegetative growth of plants. This research was conducted to study the effect of gibberllic acid (0, 250, 500 and 750 mg l-1) on annual seedling growth of Ber tree. The experiment was carried out in randomized complete block design (RCBD) with four replications. Measured parameters included: length of internodes, height of shoot, fresh and dry weight of leaf, shoot and root, leaf area and root area. The result showed that 750 mg l-1 GA3 was the most effective on the length of internodes and height of shoot and its difference with the other treatments were significantly at 1% probability. The other vegetative parameters included: leaf area, fresh weight, dry weight of leaf and shoot of seedling in high concentrations (500, 750 mg l-1) which were significantly different at 5% probability compared with the control ones. The result of this study showed that spray of gibberllic acid did not have significant effect on the root area, fresh and dry weight.