مجله علوم باغبانی ایران
سال پنجاه و چهارم شماره 4 (زمستان 1402)

The purpose of this study was to investigate the effect of light quality on some fruit quantitative and qualitative traits of grape in response to the salinity of the nutrient solution in a hydroponic system in a greenhouse, The study was carried out as a factorial experiment with two factors based on a completely randomize design and three replications over two successive years. The first factor was light quality at 5 levels including red 100%, blue 100%, red and blue with a ratio of 70 and 30%, red and blue with a ratio of 50 and 50% and the control (greenhouse natural light) and the second factor was electrical conductivity caused by adding sodium chloride to the nutrient solution at 4 levels including 1.67 (control), 3.63, 6.05 and 10.23 Ms/cm. The results of this study showed that in combination of red and blue light (70-30) treatment at 10.23 Ms/cm salinity compared to other light qualities, the weight, length, width and cluster density are of fruit were 53, 71.89, 70 and 36% respectively, more than the natural light of the greenhouse. The combination of red and blue lights increased the amount of dry matter (18.31%), dissolved solids (18.31%), titratable acid (12.51%), antioxidant capacity (20%) and vitamin C (39.49%) compared to the natural light of the greenhouse. It also caused the lowest accumulation of tannin in the fruit (29.55%) in the treatment of 10.23 Ms/cm of salinity. Blue light (100%) led to an increase in the sugar to acid ratio and anthocyanin ratio by 18.31 and 37.41%, respectively, more than natural greenhouse light in grape fruit.Therefore, the combination of red and blue lights, especially the ratio of 70-30%, showed a greater effect in maintaining and improving the quantitative and qualitative characteristics of the fruit in severe salinity treatment.

The use of drought-tolerant rootstocks, such as seeded and rainfed watermelons, and pumpkins, is an effective solution for increasing tolerance to drought stress in watermelons. For this purpose, this experiment was conducted in a greenhouse to evaluate the effects of irrigation treatment at three levels (1-0.8; 0.6 -0.8; and 0.3-0.6 FC) and rootstock type at five levels (control, three rootstocks of rainfed and seeded watermelons including Sabzevar, Khajahe and Ashtian and one rootstock of pumpkin: Shintoza) on physiological and biochemical parameters in watermelon Crimson Sweet Super Dragon F1. The results showed that the number of leaf stomata in grafted and non-grafted plants decreased with the increase of dryness levels, and the grafted plants on Shintoza rootstock had a higher stomatal density. Drought stress caused a significant decrease in chlorophyll index and leaf relative water content and increased electrolyte leakage in studied watermelons. The total antioxidant capacity and the activity of catalase and peroxidase enzymes increased as a result of drought stress, but this increase was greater in grafted plants on Shintoza and Sabzevar rootstocks than in plants grafted on Ashtian and Khajahe rootstocks as well as watermelons.. Watermelons grafted on Sabzevar and Shintoza rootstocks produced the highest content, while non-grafted and grafted watermelons on Ashtian rootstocks produced the lowest content of leaf phenolic compounds Potassium and phosphorus levels in plants with normal irrigation were higher than plants under stress. As a result, yield and vegetative growth traits were significantly affected by irrigation and transplanting treatments.

Plum fruit moth, Grapholita funebrana is one of the most important plum (Prunus domestica) pests. This project was carried from 2019 to 2021 to screen 26 cultivars and promising genotypes of plum in terms of pest larvae feeding tolerance index. The percentage of injury and the larvae population were measured every ten days until the end of October during the activity period of larvae. Then the biological stress sensitivity index was calculated. Time series models were used to investigate the correlation between injury percentage and larval population density, and the cluster analysis method was used to separate cultivars and genotypes based on tolerance index. The degree of influence of different fruit characters on tolerance was investigated by calculating Spearman's correlation coefficient. The results showed that the maximum effective day-larva index in the study years was in late July to early August. The values of cross correlation coefficient in Ghalo and Sosormi cultivars had maximum and minimum values, respectively. Finally, Queen Roza and Anjelo were the most sensitive, and Qomi, Gholaman, Faryar, G-Black, Zojlo, Gallo, G-100, G98, G99, Mortini, Black Amber and Kermanshah were the most tolerant cultivars to plum moth. Fruit surface area, sphericity index, average diameter of fruit engineering, fruit size index, fruit length and width had positive and significant correlation with tolerance indices. The results of this research are part of the breeding program of plum cultivars to develop the cultivation of this product in the country.

This study was conducted in order to investigate the changes in the growth regulators related to fruit setting in the pollination season on both tissue culture-derived and offshoot-derived date palms cv. Barhee (10 years old) in the Date Palm and Tropical Fruit Research Center of Ahvaz city. At the beginning of spring, palm trees were selected from each group of tissue culture and offshoot trees and sampling of flowers and fruits was done in the three stages including: spath appearance, ripe spath and 2 weeks after pollination in three replications. In order to evaluate fruit setting, three spathes in each palm (1-2 days before natural opening) were pollinated with Ghanami cultivar pollen by traditional method. The plant hormones including auxin (IAA and IBA), gibberellin (GA1, GA3, GA4, GA9), cytokinin (Zeatin and Kinetin), abscisic acid and jasmonic acid were measured in the flower or fruit samples collected from tissue culture and offshoot trees. Five weeks after pollination, fruit set percentage, parthenocarpic fruits percentage and flower and fruit drop percentage were recorded. The results showed that tissue culture derived plants had less fruit set percentage and more seedless fruit and fruit drop percentages compared to off shoot derived plants. Also, the fruit yield in the tissue culture plants was lower than off shoot derived plants.  The levels of gibberellin, auxin, and cytokinin hormones in the off shoot derived plants were higher than tissue culture plants in most of the measured stages.  The tissue culture plants had a higher amount of abscisic acid and jasmonic acid than offshoot plants. By using multiple linear regression analysis and superior model selection, the amount of abscisic acid and jasmonic acid of flower and fruit had a negative relationship with the amount of fruit set. The fruit setting was positively correlated with the amount of kinetin, indole acetic acid, GA3, GA4 and GA9 of flowers and fruits, while had a negative correlation with the amount of abscisic acid and jasmonic acid.

The diversity of cultivars is very important for the sustainable production of citrus. Also, there is little information about the effect of common sour orange substitute rootstocks on new cultivars. The present research was conducted to investigate the vegetative growth of six navel orange cultivars ('Fucumoto'; 'Navelina'; 'Navelate'; 'Thomson navel'; 'Cara cara' and 'Lane late navel') on three poncirus hybrids rootstocks ('Carrizo citrange'; 'Swingle citrumelo' and 'C-35 citrange'), during seven years. Traits related to vegetative growth such as tree volume, rootstock and scion morphological compatibility, leaf nutrient concentration and tree survival were measured. All measured vegetative traits were affected by year, rootstock and cultivar. The rootstocks affected the concentration of all nutrients in the leaves. Tree height and volume and the required area for orange trees on the 'Carrizo citrange' were less than the other two rootstocks. 'Navelate' and 'Lane late navel' cultivars had the highest and 'Fukumoto' had the lowest tree volume. The compatibility of the graft union decreased with the increasing age of the trees. In the last year, there was the lowest compatibitity between 'Fukumoto' cultivar and 'citrumelo' rootstock (0.60) and the highest between 'Navelate' cultivar and 'Carrizo citrange' rootstock (0.77). One tree of 'Fukumoto' and 'Navelina' with 'C-35' rootstock declined in the last year of the experiment, but other rootstocks and cultivars did not show any signs of yellowing. The maximum area required for seven-year-old trees of 18 studied rootstock and cultivar combinations with regular annual pruning was about 9.5 m2, which was recorded in 'Navelate' cultivar on 'C-35 citrange' rootstock.

In order to investigate yield, yield components and essential oil quantity of cumin as affected by cultivation and pre-soaking methods, a split plot experiment was conducted based on a randomized complete block design with three replications. The main-plot of the experiment was the cultivation method in two levels (planting in a leveled and non- leveled method), and duration of seed pre-soaking at five levels (control, 6, 12, 24 and 48 hours) was considered as sub-plot. The results showed that in both cultivation methods, the highest and lowest number of emergent plants were observed in the 12 and 48 hours seed pre-soaking treatments, respectively. In non-soaked seeds, the number of emergent plants in the leveled cultivation method was more than that of the non-leveled cultivation method, but, there was an opposite trend for the 6, 12 and 24 hours pre-soaking. In all seed soaking treatments, seed yield was significantly higher in the non-leveled than leveled cultivation method. The highest seed yield, biological yield and essential oil yield were obtained in the cultivation method without leveling, and 12 hours of seed pre-soaking. In the leveled cultivation method, the non-presoaked seeds significantly produced the highest essential oil percentage, but in non-leveled cultivation method, the highest essential oil percentage (2. 60%) was observed in 48 hours of seed pre-soaking, which it had no significant difference with other seed pre-soaking treatments in terms of essential oil percentage. Among the investigated traits, essential oil yield had the strongest correlation with the seed yield.

In order to investigate the effect of sodium nitroprusside on reducing the negative effect of salinity stress on four grape rootstocks and cultivars, a research was carried out in a factorial based on a completely randomized block design with three replications. Two-year-old rooted cuttings of all four cultivars and rootstocks (Bidaneh Sefid, Yaghouti, 140Ru and 1103P), were subjected to three levels of salinity (salinity in Cramer's nutrient solution) zero, 25 and 50 mM sodium chloride (1.3, 4.50 and 6.80 ds/m) and three levels of sodium nitroprusside (SNP) zero, 0.5 and 1 mM. The results showed that increasing salinity levels, reduced the indices of leaf relative water content and contents of chlorophyll a and b and carotenoid. Furthermore, proline, glycine betaine, soluble sugars, total phenolic, ion leakage, malondialdehyde and hydrogen peroxide increased along with increasing salinity levels. Based on the results, application of SNP, especially at a concentration of 1 mM under salt stress conditions, increased the leaf relative water content, the content of photosynthetic pigments, total phenolic, proline, glycine betaine and soluble sugars, and reduced ion leakage, malondialdehyde and hydrogen peroxide in grape cultivars and rootstocks. Use of SNP caused greater effects on ‘Bidaneh Sefid’ and ‘Yaghouti’ cultivars than the rootstocks. The results showed that ‘Bidaneh Sefid’ cultivar was sensitive to salinity, while 140Ru rootstock was more tolerant to salinity than ‘Bidaneh Sefid’ and ‘Yaghouti’ cultivars, as well as 1103P rootstock.