نشریه پژوهش های میوه کاری
سال یکم شماره 2 (پاییز و زمستان 1395)

This study was conducted to investigate some biochemical and physiological reactions of different olive cultivars (Olea europaea L.) against salinity stresses in three different experiments, experimental settings and contexts in Iran over a period of three years. In order to study the effects of salinity and penconazole combination on physiology of four olive cultivars, a factorial experiment was conducted. Studied factors were included of cultivar at for levels (Conservolea, Koroniki, Zard, Roghani), salinity stress (zero, 100 and 200 mM) and penconazole at three levels (zero, 10 and 15 mM). The results of the experiment showed that the studied treatments had significant effects on morphological factors, physiological factors, carbon dioxide levels, transpiration, stomatal conductance and photosynthesis rate of different olive cultivars. Among different cultivars, Koroniki and Zard showed higher resistance to salinity. The results of this research could be used in order to choose salinity-tolerant cultivars and cultivars with high oil quality to be used in agricultural, food, and pharmaceutical industries.

Developing new, seedless, early ripening and high quality cultivars are important goals in grape breeding programs. Nowadays, producing high percentage of seedless progeny has been possible. This study was aimed to examine the effects of ovule development stage (25, 35, 45, 55 and 65 days after pollination) and putrescine spraying (0, 20, 30 and 40 mg l-1) on size of the ovule and berry in grape Perletet cultivar during embryo rescue. Putrescine was applied at two different stages including 14 days before and 7 days after full bloom, respectively. After random collection of berries at above mentioned stages of ovule development, the ovules were removed and cultured on Nitsch and Nitsch medium containing 0.35 mg l-1 gibberllic acid and 1 mg l-1 indol acetic acid. Results showed that the effect of ovule developmental stage and putrescine pre-treating were significant on length and diameter of ovule and berry, as well as the percentage of ovule germination. The highest levels of studied traits were observed in 30 mg l-1 putrescine treatment at 65 days after pollination.

This experiment was conducted to evaluate the proline and enzymes changes after termination of chilling requirement and during heat accumulation. Four apricot cultivars including “Tabarzeh”, “Shekarpareh”,”Shamloo” and “Asgarabad” were selected at Khalaat Pooshan Agricultural Research Station, Tabriz University, Iran. In this study, changes in enzyme activity of catalase, peroxidase and superoxide dismutase as well as proline content were measured monthly just after the end of dormancy period until 50% blooming for each cultivar. Analysis of variance (ANOVA) showed that there was a significant difference in enzymes activity within different cultivars. Enzymes activity had the minimum value immediately after terminating chilling requirement while reached the maximum value during the bloom. Comparing the average superoxide dismutase, catalase and peroxidase activity in different cultivars showed that “Asgarabad“ had the highest enzyme activity in March with the 3254 Grow Degree Hour (GDH), while the least amount of enzyme activity was recorded in “Tabarze“ during February with 214 GDH. Also, significant change in proline content was revealed in studied cultivars at different sampling times, so that, the highest and lowest proline contents was observed in “Tabarzeh” with 254 GDH and “Asgaraabad” with 214 GDH, respectively.

Due to geographical and suitable climate, Iran is one of the most important viticulture regions in the world. Drought is one of biotic stresses limiting the growth and production of plants leading to reduced physiological and biochemical traitss such as photosynthesis and vegetative growth. Vinifera grape cultivars are more tolerant to drought stress and there is a high diversity among genotypes and species. In order to study the adaptability of some Iranian grape cultivars in dryland farming, this research was conducted as a RCBD design in west Azerbaijan provinces (Sardasht region). Cuttings of Rasha, Mambraima, Yaghoti, Askari, Khalili, Kolahdary, Kajangoor, Fakhri, Shahani, Perllete and Flame seedless cultivars was planted in field and trained as head prune training system. After three growing years, some quantitative and qualitative traits such as yield, berry and bunch weight, TSS, cold winter tolerance, viability percent in vineyard and harvest time was recorded. Results showed that Perllete and Flame seedless cultivars had the higher yield in two studied years than other cultivars. Yaghoti, Khalili, Flame seedless and Perllete were the early ripening cultivars, respectively. Based on earliness in ripening, higher yield with better fruit quality for marketing, Khalili, Yaghoti, Perllete and Flame seedless cultivars were superior and may be introduced as adapted and more suitable new cultivars for Sardasht region.

Sweet cherry fruit deteriorate rapidly after harvest and in some cases do not reach to consumers at optimum quality. Therefore, the use of natural compounds to increase the shelf life and maintain the quality of fruits is necessary. In this research, the effect of methyl jasmonate (at 0, 7 and 14 µmol L-1) on postharvest life and quality of sweet cherry fruits (Tak Danye mashhad cultivar) during storage at 1± 0.1 ˚C with 85-90% RH was studied and traits were evaluated after 15 and 30 days of cold storage. Fruit quality attributes including pH, total soluble solids, titratable acidity, TSS/TA ratio, total antioxidant capacity, Total phenolics content, total flavonoids, total anthocyanins, catalase, peroxidase and polyphenol oxidase enzymes activity were evaluated. The results showed that methyl Jasmonate was effective in maintaining the pH, increasing titratable acidity and TSS/TA ratio and also increasing total antioxidant capacity, total phenolics and total flavonoids content. While the increase in activity of peroxidase and polyphenol oxidase enzymes activity was prevented by Methyl Jasmonate. The treatment had no significant effect on total soluble solids content. The results of this study indicated that Methyl Jasmonate enhances postharvest life of Sweet cherry fruit via increasing total antioxidant capacity and decreasing senescence rate.

Most plants encounter with different environmental stresses during their life cycle. Water deficit is one of the stresses that negatively affect the growth and yield of many agricultural crops such as members of citrus family. Higher plants developed several physiological and biochemical adaptation systems that give them a chance to survive and let them to escape from water deficit stress. In this research the effect of Nitric Oxide, as a stress modulator, on citrus plants was investigated. A trial was conducted as factorial with randomized complete blocks design in three replications on three species of citrus including Poncirus, Swingle citrumelo and Carrizo citrange. There were also drought stress treatments in three levels (FC, 30% FC and 60% FC) and Sodium nitroprusside treatments, as a NO releasing compound, in three levels (0, 0.5 and 1 mM). Some physiological factors such as chlorophyll fluorescence, stomatal conductance, leaf water potential and leaf relative water content were measured. Also, some biochemical factors such as DPPH and the contents of phenols and malondialdehyde were investigated. The results showed that drought stress, decreased leaf water potential, stomatal conductance, relative water content and Fv/Fm significantly. Some biochemical factors such as DPPH, phenols and malondialdehyde activity increased during drought stress. Application of sodium nitroprusside, modulated the destructive effects of drought stress specially with the concentration of 1 mM.