IRANIAN JOURNAL OF HORTICULTURAL SCIENCE AND TECHNOLOGY
Year:2006 | Volume:7 | Issue:1|Papers Count:7

In order to characterize some Iranian grapevine (Vitis vinifera L.) gene pool, 72 genotypes were collected from west and north-west provinces of Iran and were genotyped along with 18 European grapevine cultivars using 12 Sequence Tagged Microsatellite Sites (STMS) markers. All of the 90 genotypes were distinguished by the 12 Ioci. The number of observed alleles per locus ranged from 4 alleles at VVMD6 to 11 for VVMD25. Expected heterozygosity ranged from 51% to 85%. The total Probability of Identify (PI) was calculated for this set of markers (2.2×10-10) that indicated high discrimination power of this set. Cluster analysis was done by UPGMA algorithm based on Jaccard similarity coefficient; this method grouped more of genotypes according to their geographical origins.

Experiments were conducted at Ashkevarat during the years of 2000 to 2002 to evaluate different pollen sources in hazelnut as a factorial experiment with a randomized complete block design with 3 replications. Main factor was pollen sources in three levels and another factor was cultivars in three levels. 'Nakhoni', 'Gerd', 'Shastak' were used as female parents and 'Daviana', 'Coxford', 'Negret' as male parents. Three trees were selected of each female cultivar in each replication. Twelve branches on each tree were selected in four geographical directions and were isolated with paper bags. Isolated branches were pollinated with three collected pollen grains. Results of pollen germination test of three pollinizer cultivars showed that 'Daviana' had the highest pollen germination percentage. Results showed that pollen sources had no effect on nut and kernel shape but had significant effect on kernel percentage, blank nuts, nut and kernel weight and fruit set percentage. 'Daviana' pollen decreased blank seed and increased fruit set, kernel percentage and nut and kernel weight. 'Daviana' pollens were better than the other pollen grains used.

Crop water stress index (CWSI) is an appropriate parameter for irrigation scheduling of most agricultural crops. Appropriate application of CWSI requires development of coefficients for individual crops. The present experiment was conducted at Badjgah region, Fars province during 2000 to 2001 years using four levels of water treatmentas 100%, 75% and 50% potential evaptranspiration and dry land for saffron in four replications. The purpose of this research was to develop upper and lower limits of CWSI equations for irrigation scheduling of saffron. Based on the results, the differences in canopy and air temperatures (Tc,Ta) for well-irrigated treatment had a good correlation with vapor pressure deficit (Tc-Ta=12.2-0.25*vpd, R2=0.95). The upper limit for the stressed treatment was 11oC. CWSI for optimum irrigation of saffron was 0.04. CWSI was calculated using upper and lower base lines and its capability for irrigation scheduling was evaluated. The results showed a good correlation between the CWSI and plant water status.

Kordestan province has the largest area of the strawberry production in Iran. Prevailing cultivar under cultivation is 'Kordestan' (a short-day plant). The June-bearing strawberry cultivars are facultative short-day plants and both flower initiation and runner formation depend on day length and temperature. The aim of this study was to investigate photosynthesis changes and vegetative growth during flower induction and differentiation. Results indicated a noticeable increase in photosynthesis rate at the 3rd, 4th and 5th weeks from the beginning of short-day treatment. No significant differences were observed in chlorophyll content and specific leaf weight. Stomatal conductance, water use efficiency and mesophyll efficiency showed a positive increase at the 3rd and 4th weeks in induced plants. Number of runners and crowns and petiole length increased significantly in non-induced plants compared to induced plants. Fresh and dry weights of shoot and root and their ratio in non-induced plants were higher than induced plants.

This study was carried out in the year 2003 to investigate the effects of different water regimes (40, 60, 80, 100 and 120% of water requirement) and different amounts of nitrogen (60, 120 and 180 kg ha-1) as well as their interaction on quantity and quality of tomato ‘Early Urbana’. The experiment was performed in Research Farm of Faculty of Agriculture, Tehran University (a semi-arid area) on a clay loam soil, using a split plot design with three replications (irrigation treatments as the main plots and different amounts of nitrogen as sub-plots). Results indicated that different treatments of irrigation and nitrogen as well as their interaction have significant effects on tomato quantitative and qualitative characteristics including total yield, marketable yield, number of fruits per plant, average fruit weight, water use efficiency (WUE), early ripening, dry matter, total soluble solids, terrible acidity, pH, vitamin C, firmness and N-NO3. The maximum marketable yield and WUE were obtained at 100% water requirement with 120 kg ha-1 nitrogen (78.83 t ha-1 and 0.085 t ha-1 mm-1, respectively). In this study, third order and second order functions were obtained between applied water and marketable yield, and nitrogen and marketable yield, respectively. Also a multiple regression was found between marketable yield and water and nitrogen consumption.

In recent years, fading disorder was one of the most important factors that produced some problems for date production. The disorder occurs very suddenly and rapidly in conversion of khalal to rotab stages, causing fade and eventually desiccation of dates berries. Recent studies showed that weather fluctuation especially sudden drop of air humidity in addition to high temperature and blowing hot and dry winds during transition from khalal to rutab stage have had significant influence on incidence and development of this disorder. This experiment was done conducted to study the effects of some plant growth regulators on bunch fading disorder in randomized complete block design (RCBD) with nine treatments and four replications on ‘Kabkab' in Bushehr province during the years of 2002 to 2003. The treatments were gibberellic acid (100 and 150 mg l-1), ethephon (300 and 400 mg l-1), benzyladenine (100 and 200 mg l-1) naphthalenacetic acid (50 and 100 mg l-1) and control. The data of the two years were combined and analyzed and the means of the treatments were compared using Duncan’s multiple range test. Results showed that plant growth regulators had significant effects on fading disorder reduction. Although there was no significant difference between four plant growth regulators, NAA (100 mg l-1) had the greatest effects. Fruits weight, length and diameter were affected by plant growth regulators. However, the yield was not affected by these growth regulators.