نشریه به زراعی نهال و بذر
سال سی و یکم شماره 1 (1394)

This research was carried out in split plot experiment based on randomized complete block design with three replications at Behbahan Agricultural Research Station for two years (2011–2013). The main plot consisted of sowing times 26 June, 11 July and 26 July and sub plot was five genotype L5-84215, L5-86365 and Safiabadi lines, Yellow white cultivar and Behbahan local population. Two years combined variance analysis results showed that the effects of sowing time, genotype and interaction effects of sowing time and genotype were significant on seed yield and yield components. The heightest seed yield in the first and second years was produced on 26 June and 26 July sowing times (1281 and 889 kgha-1, respectively). The heightest seed yield was produced by Behbahan local population and Yellow white cultivar (1417 and 1151 kgha-1 in the first year and 916 and 752 kgha-1 in the second year, respectively). The results of interaction effects of sowing time and cultivar showed that in the first year the heightest seed yield was produced by Behbahan local population and Yellow white on 26 June sowing time (1688 and 1449 kgha-1, respectively) and in the second year the heightest seed yield was also produced by Behbahan local population and Yellow white on 26 July sowing time (1217 and 982 kgha-1, respectively). Seed yield of all genotypes in the first year decreased from 26 June 26 July sowing times. Due to the damage of charcoal rot disease on 26 June and 11 July sowing times, the heightest seed yield was produced on 26 July sowing time in the second year. The heightest and the lowest seed yield of genotypes in the second year was produced on 26 July and 26 June sowing times, respectively. Therefore, due to the possibility of outbreak of charcoal rot disease at the end of June to mid July, planting of Behbahan local population and Yellow white cultivar at the end of July is recommended in Behbahan region.

In order to evaluate the effects of NaCl on some morpho- physiological traits in almond and alteration of photosynthetic parameters, an experiment was performed based on completely randomized design with five treatments included 0, 25, 50, 75 and 100 mM of sodium chloride in three replications. The results indicated that the contents of sodium and chloride were increased in almond seedlings but quantities of relative water content, chlorophyll index and dry weight of leaves were decreased in parallel with augmentation of salt levels significantly (p ≤ 0.05). In these conditions, alterations of leaf temperature were not significant but the seedlings percentage indicating marginal leaf scorch symptoms was increased up to 89% with relatively regular template. Applied salt in the lowest level enhanced the mean of internal CO2 and metabolic-stomatal limitation up to 35 μmol.mol-1 and 39.5% as well as decreased the mean of CO2 assimilation and stomatal conductance up to 6 mol.m-2.s-1 and 0.15 mol.m-2, respectively (p ≤ 0.05). In this probe, high efficiency of some measured traits such as relative water content, chlorophyll index and marginal leaf scorch symptoms was revealed in quick screen of the salt tolerant genotypes.

The effect of seed rate on grain yield and yield components of rice (cv. Hashemi) in direct seeding methods was evaluated in a split plot lay out based on randomized complete block design with three replication and three seeding methods as main plots and three seeding rates (60, 80 and 100 kgha-1) as sub plots at Rice Research Institute of Iran, Rasht in 2010 and 2011. Seeding methods consisted of drum direct seeding, hill wet seeding, broadcasting and pre-geminated seeding in puddle field. Results indicated that, the maximum plant height (131.0 cm), number of productive panicles (235 panicles m-2), grain yield (2753 kgha-1), Sink strength index (132.2 cm), yield formation rate (29.7 kg day-1), milling recovery (68.0%) and head rice (59.0%) were obtained in hill wet seeding method. The maximum number of productive panicles (243 panicles m-2), grain yield (2486 kgha-1), and yield formation rate (26.5 kg day-1) were obtained in in 100 kgha-1. As the results indicate, it seems that, it is possible to obtain an acceptable grain yield in Hashemi rice cultivar using direct seeding with hill wet direct seeding method in puddle field and seeding rate 100 kgha-1 in climatic continental of the experimental region.

Artificial seed production is now an outstanding technique for plant propagation and preservation, and has been applied on many plants. This investigation was carried out to study the effect of nutrients and plant growth regulator application in encapsulated matrix on regeneration and growth of synthetic seeds in two Iranian sunflower hybrids. Somatic embryos derived from the culture of sunflower immature zygotic embryos were encapsulated using 3% sodium alginate and 100 mM calcium chloride. Alginate matrix was provided with three different matrixes including distilled water, liquid MS medium and plant growth regulators and then regrowth ability was determined for synthetic seeds during four weeks after culture on Murashige and Skoog (MS) medium without plant growth regulators. The results of analysis of variance showed that plant regeneration from encapsulated somatic embryos and establishment of plantlets were affected by the presence or absence of MS nutrients and plant growth regulator in calcium alginate beads. Using MS nutrients resulted in production of stronger plantlets and the presence of plant growth regulator in calcium alginate beads produced more number of shoots and leaves and more root extension in plantlets.

Pomegranate (Punica granatum L.) is one of the most important horticultural crops in Iran that it is mostly grown in arid and semiarid regions. Due to water resources limiting in these areas, trees are always under drought stress. For evaluation of the effects of drought stress on growth, yield and fruit quality of pomegranate, this research was carried out in Agricultural and Natural Resources Research Center of Yazd located in dry climate. The irrigation treatments included100% of field capacity (no stress), 75% of field capacity (moderate stress) and 50% of field capacity (high stress) performed in randomize complete block design with four replications and nine trees per each plot. The results showed that pomegranate trees applied several mechanisms for drought resistance such as increasing cell turgid by accumulation of soluble sugars and proline, increasing water potential for more water absorption from soil, chlorophyll and carotenoid pigments preserved by control of leaf relative water content (RWC), reducing leaf area and reducing leaf area specific. Effect of drought stress on yield and fruit quality was higher than the growth characteristics. Drought stress reduced yield, fruit size and the amount of fruit components such as aril, seed, peel and juice. Drought stress increased fruit total soluble solid (TSS), titrtable acidity (TA) and reduced pH. Because of suitable vegetative conditions, good yield performance and improved quality of fruits, scheduling of irrigation based on 75% of soil moisture during the growing season with using of Babler irrigation systems in pomegranate orchards can be recommended based on the results of this study.

To determine the suitable planting date and seeding density of two triticale genotypes in Mashhad climatic conditions during 2007-2009 growing seasons, an experiment was carried out, using a Split-factorial based on randomized complete block design with three replication, at Torogh Agricultural and Natural Resources Research Center, Mashhad, Iran. Main plots were devoted to five planting dates and sub plot were factorial combination of three planting densities and two triticale genotypes. Planting dates were Oct. 7, Oct. 22, Nov. 6, Nov. 21 and Dec. 6 and triticale genotypes were: ET-79-17 and Sanabad. The results showed that, the effect of planting date on grain yield, biological yield and number of grain per spike was significant. The highest grain yield was oblained from second planting date (Oct. 22) and delay in planting date decreased grain yield. Delay in planting date, decreased yield in average of 55 kg ha-1 per day. However, results showed that the best planting date for triticale genotypes was Oct. 22 in Mashhad climatic condition. The effect of seeding density on biological yield was significant and with increasing seeding density, biological yield was decreased. There was no significant difference among seeding density for grain yield and the 250 seeds per m2 was the best density for triticale. Significant differences were not observed between two genotype concerning grain yield and other traits.

This study was conducted to assess the variability of physiological traits of wild types of Berberis vulgaris in different growing areas and altitudes in Shahrood. The experiment was carried out as factorial in the basis of randomized complete block design with three replications during 2011-2012 cropping season. The first factor consisted of three growing areas Tange Heidar Valley, Glierd and Valley of Ghatar Zereshk, and the second factor was three altiludes 1400-1650, 1650-1900 and 1900-2150 meter from sea level. Five physiological traits were assessed in randomized samples of the shrubs taken at different growth stages and different parts of the plants. The results showed significant differences in physiological traits in different growing areas and different altitudes. Anthocyanin content (46.44 mg/100mg), Berberin content (15.66%), pH of fruit (3.08) and total soluable solids (20.22 %) decreased with increase of height from sea level, while acidity of fruit increased with height. Significant negative and positive correlations were observed between different traits in different growing areas and different altiludes.