فصلنامه پژوهشهای زراعی در حاشیه کویر
سال چهارم شماره 4 (زمستان 1386)

In order to study drought tolerance of 16 genotypes of safflower an experiment was conducted in Research Farm of Shirvan Islamic Azad University during 2004 –2005 growing season. The experiment was performed as a Randomized Complete Block Design with 4 replications in two separate irrigated and dry land conditions. Length of each plot was 1/5 with 5 meters in width. The seed rate was 20 seeds per square meter and planting method was by hand. During growing season some agronomic traits as days to maturity, number of heads per plant, seed yield of total head per plant, TKW and seed yield per plot were recorded. Drought tolerance index, Drought susceptibility index. Electrical conductivity and Relative water content used to select drought tolerant genotypes. The results showed that two genotypes of LRV-51-51and CW74 had higher drought tolerance index and lower drought susceptibility index compared with other genotypes. Drought tolerance index in these two genotypes in order were 1.22 and 1.18 and Drought susceptibility index were 0.8 and 0.49.These two genotypes also produced in order 1140 and 1089 gram seed per plot that were greater than other genotypes. The seed yield of these two genotypes in dry land condition in order were 882 and 921 gram per plot that were greater than other genotypes as well. In irrigated condition, LRV51-51, HARTMAN, PI-53759 in order produced 1089, 1126 and 1116 gram seed yield per plot that were greater than other genotypes. According to results of these experiments two genotypes of LRV-51-51 and CW74 are advisable to plant in dry and low rainfall region.

In this research experiment the interactions between two types of irrigations (furrow & tape) and four levels of nitrogen (0, 60,120,180kg/h) and three levels of phosphorus(0,30,60kg/h) were studied. The sugar beet variety 7233 was used. This experiment was conducted in the field station of Sugar Beet Seed Institute in Kamal-Shahr (Motahhari Station), Karadj in 2006. Experimental design was split factorial design which two types of irrigations were in main plots and factorial combination of four levels of nitrogen & three levels of phosphorus were in subplot using randomized complete block design with three replications. Results showed that water use efficiency in tape irrigation system was 1.66 higher than furrow irrigation. The number of established plants, percentage of bolting, above ground biomass, total seed yield in tape irrigation was more than furrow irrigation too. However, although the percentage of germination, one thousands seed weight, percentage of standard seed size yield (3.5-5.5 mm) and amount of plant phosphorus in furrow irrigation system were higher than tape irrigation system, those in but the differences were not significant. The numbers of established plants, percentage of bolting were not effected by the different levels of nitrogen or phosphorous. But, by increasing the levels of nitrogen or phosphorus the total biomass, above ground and total seed yield increased. The results of this experiment showed that since the tape irrigation system increases the total seed weight and decrease the consumed water, cloud be replaced with furrow irrigation system. In addition, on the basis of results of this test, application of 120 and 60 kg/h nitrogen and phosphorous are recommended.

In order to evaluate the effects of planting date on yield and yield components of winter safflower cultivars, this study was carried out in Agricultural Research Center, Markazi Province in 2003. A split-plot arranged of treatment in a randomized complete block design with four replications was used. Planting dates (7/10/2002,22/10/2002, 6/11/2002,21/11/2002,6/12/2002) were assigned in the main plots and cultivars (L.R.V. 51-51, zarghan-279,varamin –259) in sub plots. Each sub plot consisted of 4 rows, 5 m long with 50cm between rows and 5cm between plants on the rows. In this study characteristics such as: plant height, umber of branches per plant, number of grain per boll, 1000 grain weight and grain yield were assessed. Results indicated that second planting date with grain yield (2742 kg/ha) and L.R.V. 51-51 variety with grain yield (2619 kg/ha) were significantly superior to the other treatments. The purpose of fourth and fifth planting dates was to study the safflower dormant seeding with the climate Arak zone.

Yogurt proteolysis is conducted by proteolytic activity of yogurt bacteria. Proteolysis of milk proteins increases soluble nitrogen compounds and releases amino acids and peptides. In this study, native microbial strains isolated from two traditional yogurt samples (Gilan and Golpayegan) were used for yogurt production. Total nitrogen, non protein nitrogen and protein nitrogen of yogurts produced by native starters were measured. SPSS software was used for statistical analysis. Produced yogurts were stored at 4°C for three weeks. The aim of this study was to evaluate the variations of non protein nitrogen, protein nitrogen and proteolysis depth of produced yogurts during cold storage. There was a significant increase (p< 0.05) in non protein nitrogen and a significant decrease (p< 0.05) in protein nitrogen of produced yogurts during cold storage. Moreover, proteolysis depth increased significantly (p<0.05).

This study was conducted to determine the effects of phase feeding on broiler performance. A total of 240 day old male and female Ross 308 chicks were used in a completely randomized design in 4 treatments and 3 replicates for each treatment and 20 birds per replicate. The first treatment was considered in 3 phase schedule. The second treatment included pre-starter, starter, grower 1, grower 2, finisher 1 and finisher 2 with 24, 22, 21, 20, 19 and 18 percent CP respectively. The third treatment was scheduled in starter (0-14) with 22 percent CP, grower (15-28) with 21 percent CP and finisher (29-42) containing 18 percent CP. The fourth treatment included starter (0-21) with 21 percent CP and finisher (22-42) with 19 percent CP. There was no metabolizable energy variation between the diets: 3010 Kcal/Kg for the starter diet, 3175 for the grower and 3225 for the finisher.According to the results, feed consumption, body weight gain and feeding conversion ratio were significantly affected when feed phases were increased (p<0.05), but carcass composition was not influenced (p>0.05).To determine the economical performances, feed consumption cost, metabolizable energy, CP, digestible lysine, threonine and sulfur amino acids consumption per Kg of weight gain were calculated and analyzed. Economical traits were significantly influenced by increasing feed periods (p<0.05). The first and the second treatments led to the best performance but the fourth one caused the worst. Production index which is one of the most important economical traits was also evaluated. Means comparison showed that increasing feed phases had a significant effect on this trait (p<0.01). Second treatment had the best and the fourth one had the worst effect on the production index. According to the results, increasing feed phases leads to a trend of meeting age-related requirements of chickens. Hence, better daily weight gain and other improved performances will be obtained.

Root depth and spreading have an important role in drought resistant and better use of soil moisture. In order to study the root characters and their impact on drought resistance in canola genotypes, an experiment was carried out at Research farm of factually of Agriculture in Tabriz University, Iran. Genetic material consisted of Global, Puma, Regent, Eureka and PF 7045.91 from napus species, Sonja and Parkland from Rapa species and two hybrids namely Hyola308 and Hyola401. This experiment was carried out under two conditions namely normal and water deficit environments arranged in randomized complete block design with 8 replications. Water deficit was induced by stopping the irrigation at 50% flowering. Canonical correlation analysis showed high correlation between root morphological and shoot related characters under both normal as well as water deficit environments. Cultivars with higher shoot dry weight, plant height and number of silique prove to have higher maximum root length, root volume and root thickness. Root morphological characters including maximum root length, root volume, root thickness, root dry weight had important impact on drought resistant by physiological indices and increased yield. Higher root volume will cause higher number of silique and plant height under water deficit condition.

In order to study the effects of sowing date and plant density, yield components, some vegetative characteristics and developmental stages, oilseed rape (var. regent), this experiment was conducted in Dasht- e – Naz, Sari of Mazandaran Province. A split plot design with four replications was used. Sowing dates (7 and 22 October and 15 November) and within row spacing (3, 6, 9 and 12 cm) were considered as the main and subplots, respectively. The effects of sowing date on the number of days from planting to germination, four- leaves stage, flowering and maturity were significant and late planting delayed germination and the occurrences of four- leaves stage, but flowering and maturity stages were accelerated. Plant spacing and interaction between sowing date and plant spacing had no significant effect on development stages. Early planting increased vegetative characteristics. At the first sowing date, because of favorable environmental conditions, plant height, number of secondary branches, plant dry weight and biological yield were increased. Stem thickness, number of secondary branches and plant dry weight were increased with increase in plant spacing. Number of pod per plant and square meter and 1000 seed weight were affected by sowing date and early planting increased them, but the number of seed per pod was not affected by sowing date. Among the yield components, number of pod per plant increased with decreasing of density, but number of pod per square meter decreased. Seed yield and oil percentage were affected significantly by sowing date and plant spacing. Early planting increased these traits and the maximum yield obtained for 3 cm within row spacing. The maximum yield per plant and oil percentage was obtained with 12 cm within row spacing. The results showed that 1000 seed weight, number of pod per square meter, number of seed per pod and plant height were the most casual of yield variation and 1000 seed weight explained 76% of its variation. Seed yield showed heigh correlation with 1000 seed weight, number of pod per square meter, plant height and oil yield.

In order to optimiz of using phosphate fertilizer in farm of corn grain cultivar, a factorial experiment within a randomized complete blocks design with four replications was conducted in research farm of Islamic Azad University in Varamin, Iran in 2005. The factors in this study included cultivars and phosphate source Cultivars consisted of two levels: single cross 704 (C704) and single cross 700 (C700). Phosphate source was of 4 levels as follows.P0(non-application of phosphate fertilizer), Pc(application of chemical phosphate fertilizer at the rate of 150 kg/ha), Pcb(application of chemical phosphate fertilizer at the rate of 150 kg/ha combinaed with Pseudomonas putida and Bacillus lentus as phosphate solver bacteria) and Pc/2b (application of chemical phosphate fertilizer at the rate of 75kg/h in combination with Pseudomonas putida and Bacillus lentus as phosphate solver bacteria).Number of rows per ear, number of grains per row, number of grains per ear, weight of one thousand seeds, oil percent,, phosphor percent and yield were measured. Analysis of data indicated that the highest number of grains per row, number of grains per ear, weight of one thousand seeds, oil percent, phosphor percent and yield were obtained when treatment phosphate solver bacteria was employed, which was significantly different in comparison to treatments P0 and Pc. Also the results showed that when phosphate solver bacteria was employed, the amount of phosphate chemical fertilizers application is cut down to 50%.