مجله علوم و فنون باغبانی ایران
سال بیست و یکم شماره 4 (زمستان 1399)

In order to evaluate the effects of fruit maturation stages on physical and phytochemical characteristics in sour orange, a factorial experiment was performed based on complete randomized block design (RCBD) with two factors and four replications. Four maturation stages of the fruit including green immature, half-ripened, ripened and over ripened stages constituted the first factor and different parts of the sour orange fruit containing flavedo, albedo, fruit juice, dross and seed built up the second factor. The results demonstrated a significant effect of maturation stage on most of the measured traits (essential oil percentage and yield, fresh and dry weight of fruit parts, flavon and flavenol content, total flavonoid, phenolic compounds and antioxidant activity). Essential oil content in sour orange peel varied between minimum 3.13 % (v/w) to maximum 10.30 % at over ripened stage and green immature stage, respectively. This factor significantly decreased during fruit maturation. The maximum antioxidant activity (75.79%) related to albedo tissue at half-ripened stage. Phenolic compounds decreased during fruit maturation (from 12.38 to 6.39 mg gallic acid/g dry matter). Generally, flavedo tissue at the green immature stage contained the maximum bioactive compounds rate concerning most of the traits.

The plant growth and development are affected by oxidative stress under water deficit condition. The aim of this study was to investigate the effect of ascorbic acid as a strong antioxidant against oxidative stress caused by dehydration stress in olive trees cv. Mahali Baghmalek. In this study, two-year-old potted olive plants were exposed to three irrigation levels (100, 66 and 33% of plant evapotranspiration) and four levels of ascorbic acid (0, 250, 500 and 750 mg L-1). Some biochemical parameters and enzymes activities were measured. This experiment was done as factorial experiment based on a randomized complete blocks design with three replications in 2015-2016. The highest chlorophyll a content (1.3 mg g-1 FW) was related to trees treated with 250 mg L-1 of ascorbic acid. Also, the highest amount of total soluble carbohydrates (9.5 mg g-1 FW) and proline (2.17 µmol g-1 FW) were obtained in plants irrigated with 33 and 66 % ET crop. Foliar application of ascorbic acid at 250 and 500 mg L-1 resulted in the accumulation of total soluble carbohydrates and reduction in the activity of antioxidant enzymes such as catalase, peroxidase and oscorbat peroxidase. Therefore, according to the results of this experiment, it can be suggested that the use of ascorbic acid at a concentration of 250 and 500 mg L-1 improved some biochemical properties and reduced the activity of antioxidant enzymes in olive cv. Mahali Baghmalek under water deficit stress (33 and 66% evapotranspiration).

In order to investigate the effect of foliar application of nano-chelate calcium and potassium on quantitative and qualitative characteristics of Zardanar pomegranate fruit, a factorial experiment was conducted in a randomized complete block design with three replications in 2018 in Sidan-Farooq section. Treatments included control, nano-chelate calcium (at concentrations of 2.5 and 5 mg L-1) and nano-chelate potassium (at concentrations of 2 and 4 mg L-1). Spraying was done 45 days after full bloom as well as 30 and 14 days before harvest and kept in cold storage for 1.5 and 3 months. Quantitative and qualitative characteristics were investigated before storage and after storage. Spraying of nano-chelate calcium and nano–chelate potassium compared to control resulted in an increase in total weight of aril, reduced weight loss, and brownish skin index of the fruit skin during storage. During cold storage, the highest amount of soluble solids and the lowest amount of acidity were observed in nano- chelate calcium treatments. Nano- chelate calcium and nano- chelate potassium could increase the brightness and chroma value in the fruit skin. It could be concluded that nano- chelate calcium in comparison with nano-chelate potassium have a significant effect on the improvement and preservation of qualitative and quantitative properties of pomegranate fruits during cold storage periods.

Recently, new and various methods such as anti-transpiration coatings are used for increasing the quality of pomegranate fruit. In the present study, the effect of antiperspirants and shading net on physiological characteristics of pomegranate fruits of Malas Saveh cultivar was investigated in 2017. The experiment was based on a completely randomized design in three replications with eight treatments including control, talc, zinc oxide, silica, kaolin, TSZ (talc, silica, zinc oxide), TSZK (talc, silica, zinc oxide and kaolin) and shading net. Foliar application of all treatments was carried out at 2% concentration in both late June and early August. Important physiological factors of fruits including color and anthocyanin, vitamin C, and sugars content were evaluated. The results showed that TSZK and talc increased fruit diameter by 5% and 10%, respectively. The shading net reduced fruit sunburn by 100% compared to the control. Shading net, talc and silica caused a five to eight percent increase in vitamin C in comparison to the control. Shading net, talc, kaolin, and TSZ increased fruit TSS by two to three percent. However, the anti-transpiration materials improved some of the fruitchr('39')s qualitative characteristics and improved skin color, reducing the number of burnt fruits by reducing fruit temperature by five to seven centigrade.

It is important to study the morphological diversity of native almond genotypes with the aim of selecting and introducing new cultivars. In this study, 30 native collected genotypes and six commercial cultivars of almond were evaluated in terms of 22 quantitative and qualitative traits of nut and kernel. High diversity was observed for nut weight, shell color, shell hardness, shell opening, kernel taste, and kernel percentage among evaluated genotypes. Cluster analysis based on index traits divided these genotypes into five groups. The genotypes ALC203 and ALC413 and the cultivars Non-pariel, Yalda, and Manaqha which were located in the second cluster, had thin shell with high percentage of kernel that are important for nut consumption. In principal components analysis based on the average of 10 index traits, the first three main components explained a total of 80.75 % of the diversity of traits. In the first main component, nut weight, shell thickness and shell hardness and in the second main component, nut and kernel size had the major part in the separation of genotypes. Shell hardness had significant positive correlation with shell thickness and nut weight. Kernel percentage had significant negative correlation with shell thickness and its hardness but showed positive correlation with shell opening. These results are useful for selecting new promising genotypes of almond.

For successful establishment of an almond orchard, the choice of an appropriate rootstock has a great importance. Recently, wild almond species have been highly regarded because of high genetic diversity, resistance to biotic and abiotic stresses as well as the ability to produce inter and intra specific hybrids. This research was carried out to investigate the graft compatibility and also the interaction of different rootstock-scion combinations including two ‘Non Pareil’ almond and ’Shablon’ plum as scion and nine different seedling rootstocks including domesticated and wild almond species as well as some of their inter specific hybrids, during two consecutive years (2016-2017). Measurement of vegetative growth parameters in two stages before budding showed that peach × almond hybrid rootstock had the highest growth rate. The highest and the lowest percentages of final budding success in both plum and almond scions were observed in bitter almond seedling rootstock (82.50 and 80.46%, respectively for plum and almond scion). This is the lowest rate of budding success in both scion cultivars were recorded in hybrid seedling rootstocks of peach × almond hybrid (14.66 and 36.60%, respectively for plum and almond scion). Considering the growth indices of scion cultivars after budding, P. dulcis × P. elaeagnifolia hybrid rootstocks and P. scoparia were the rootstocks having the highest and the lowest plant height and trunk diameters. The maximum and minimum amount of total chlorophyll were measured in peach × almond and P. elaeagnifolia × P. scoparia hybrid rootstocks, respectively. The absorption of all of measured elements (potassium, zinc, iron, and manganese), except phosphorus, were significantly affected by rootstocks. In general, investigated rootstocks especially hybrids had good compatibility with both plums and almonds. Due to the diversity of growth and physiological traits as well as the different ability to absorb nutrients, hybrid rootstocks can be considered as the potential rootstocks for almond and plum in different climatic and soil conditions.

The objective of this study was to investigate the effects of humic acid and salinity on the growth and chemical composition, and some biochemical properties of Aloe vera. The experiment was conducted as a factorial arranged in a completely randomized design with three replications under greenhouse conditions. Treatments consisted of three salinity levels (0, 60, and 120 mM) and three humic acid levels (0, 150, and 300 mgL-1). Some plant properties such as height, root length, leaf and root dry weights, total chlorophyll content, the ability of reactive oxygen species scavenging (DPPH: Diphenylpicrylhydrazyl), and some nutrients concentration were measured. The results showed that application of 120 mM salinity significantly decreased plant height (7%), root length (47%), leaf and root dry weight (26, 50%), total chlorophyll content (45%), leaf P (15%) and K (23%) concentrations, and significantly increased ability of reactive oxygen species scavenging (DPPH) (20%) and Na concentration (113%). Application of 300 mgL-1 humic acid significantly increased plant height, root length, root dry weight, total chlorophyll content, and DPPH in Aloe vera. Interaction of salinity and humic acid did not have any significant effect on the studied properties.

Heavy metal contamination has become a serious environmental problem. The effects of 0, 30 and 60 mgL-1 Cu in the irrigation water and, 0, 2 and 4 mgL-1 sea algal extract (Ascophyllum nodosum) foliar applications on the growth and some physiological characteristics of Lepidium sativum were studied. The experiment was factorial based on RCBD. Malondialdehyde content was affected by 60 mgL-1 Cu treatment. Plant dry weight, total phenolic content and proline, Cu2+, K+, Mg2+, Fe2+ contents as well as catalase and peroxidase activity were influenced by the interaction effects of Cu treatment and foliar application of A. nodosum. For proline content, Cu control × 2 and 4 mgL-1 foliar application of algal extract was the treatment of choice. The lowest amount of total phenolics content was recorded with control plants. Peroxidase and Cu2+ content hold the top quantities at Cu of 60 mgL-1 × non foliar applications. Plant dry weight had the highest data for Cu control × 2 mgL-1 foliar application and Cu of 30 mgL-1 × 2 mgL-1 algal foliar application. The data clearly shows that algal extract; due to the abundance of some nutritional elements reduces the toxic effects of Cu metals on plants.

In this study, the effects of different hydrogen cyanamide (HC) concentrations (0, 3, 4, 5 and 6) on flowering and fruit quality of Hyaward kiwifruit during 5 weeks before normal budbreak was investigated. The results showed that HC spray advanced budbreak for 9 days, even and short bud break period for 9 days as compared to control. Treatments of 4, 5 and 3% HC showed budbreak of 67.74, 65.9, 63.73 %,respectively as compared to control (58%). Kiwifruit vines sprayed with 3 and 4% HC showed the highest king flower per winter buds with 2.11 and 1.55, respectively as compared with control (1). The highest fruit yield was found in 5, 4 and 3% HC treatment with 103, 99 and 90 kg per vine and the lowest value was found in control and 6% HC with 51 and 63 kg per vine, respectively. The mean fruits weight of HC treated vines ranged 110-134 g as compared to control (100 g). No significant difference was found between HC treated and control vines for fruit soulable solid content, dry matter and firmness. Overall, the results showed that HC treatment specially at concentration of 3% increased fruit yield by increasing king flower number per winter buds, without negative effects on fruit internal quality.

Improving water use efficiency in horticultural crops can be achieved by adopting appropriate practices. An experiment was conducted to reduce water stress in Peach var red top grafted on GF677. The experiment was arranged in a factorial completely randomized design with three replications. The treatments consisted of bag placement beyond tree trunk (0, 1 and 2 bag/tree), irrigation rate (50, 75 and 100 % of field capacity) and fugues (0, Mycorrhiza and Trichoderma). The results indicated that the highest content of chlorophyll and fruit number were observed in 2 bag 100 irrigation and Trichoderma treatment which 18% was higher than that of control. The increased both trunk diameter and stem growth were achieved in the treatment 0 bag, 100 irrigation, Mycorrhiza, 1 bag, 75% irrigation and Trichoderma, respectively. Treatment 0 bag, 75% irrigation and 0 fungi had the highest content of total soluble solid (TSS) and TSS/Titratable acidity. In general, the treatment of 1 bag, 75% irrigation and Mycorrhiza led to increased growth, yield and quality of fruits.

In this research, bearing status and fruit quantity and quality traits in some apricot cultivars in Karaj condition were studied. Flowering time range was one week. The percentage of pollen germination (50.4-80.8 %), pistil length (5.24-9.13 mm), ovary diameter (0.96-1.83% mm) and double pistils (0-31 %), Initial fruit set (0.3-38.8 %) and finally fruit set (0.1-30.5%) were obtained. Also, ripening time range was 35 days and fruit development (86-118 days) and yield of cultivars (3-38.3 Kg tree-1) were attained. The studied cultivars were round in shape and their fruits weight range was 24.5-51.8 g. The stone weight included a lower percentage of fruit weight (3.3%) in the ʻAmeneh Dizbadʼ. The skin hue angle was obtained as 85.1-99.5 degrees. The highest TSS (19.47˚ Brix) was observed in the ʻShahroodiʼ. All cultivars had a low TA (<0.7%). The pH juice range was 4.6-5.9. Antioxidant capacity (22.53-28.53 %), vitamin C (6.37-20.53 mg 100ml-1 Juice), and total phenol (176.62-330.31 mg GAE 100g-1 FW and flavonoid contents (3.21-5.57 mg Q 100g-1 FW) were obtained. Fruits of ʻAmeneh Dizbadʼ, ʻShahroodiʼ, and ʻRajabaliʼ were among superior cultivars that seems to be good for fruit production in Karaj conditions.

No negative effects on fruit quality is essential for the practical use of Beauveria bassiana as a substitute for methyl bromide in date fruits disinfection. Experiment was conducted in a completely randomized design with two level factorial arrangements. The first factor included three cultivars including Sayer, Zahed and Deiri and the second factor consisted of inoculation with fungal spores and control. The fruits of dates cultivar, Zahedi, Deiri and Sayer, were treated by doses of 5.21×104 2.46×104 and 2.69×104 spores/ml, respectively. The results showed that biopesticide treatment could not change the physiological characteristics of the fruits compared to the control. Although biopesticide treatment was effective in maintaining the quality of all studied date cultivars, it had the greatest effect on Deiri date cultivar. This method reduced the accumulation of sugar in the fruit. Absorption or loss of fruit moisture due to treatment was negligible. The concentration of soluble solids in the fruit extract was not affected by the treatment, but changes were observed in the three studied dates cultivars during the six months of storage, which indicates the importance of treatments to increase the length of the shelf life.