مجله علوم و فنون باغبانی ایران
سال بیست و یکم شماره 3 (پاییز 1399)

Perishability and short shelf life of blackberries fruit is the most important limiting factor in their post-harvest. In this study, three types of blackberry fruits (spring, summer and autumn bearing) with three storage times (0, 3 and 8 days) in two packaging (biodegradable and non-biodegradable) in factorial in a randomized complete design with 3 Repeat at 4 °C and 85% relative humidity. The results showed that the apparent quality of fruits decreased with increasing storage time. Spring fruits showed more reduction in aroma and color than other fruits. The amount of total anthocyanin in summer fruits decreased from the beginning (276.98 mg 100g-1) to the end of the experiment (23.38 in the biodegradable container and 34.18 in the non-biodegradable container). Anthocyanin levels of spring fruit (floricane bearing of Rubus Sanctus) and autumn fruit (primocane bearing of Rubus Sanctus) fluctuated in different containers. The amount of phenols of spring fruits decreased with increasing storage time in biodegradable containers (58.31 mg 100g-1) and increased in biodegradable containers (62.32). This increase can be due to water loss and increase in cell sap concentration and decrease due to decomposition. Storing this fruit in biodegradable containers compared to biodegradable containers can have less negative effect (17%) on maintaining this important feature.

The present study was conducted to investigate the effects of nitrogen (N) and potassium (K) on growth, yield, qualitative traits and antioxidant capacity of sweet fennel. The experiment was performed according to the factorial experiment based on randomized completely block design with three replications in two years (2017 and 2018). Treatments included four different levels of N (0, 50, 100 and 150 kg ha-1, urea source) and K (0, 50, 100 and 150 kg ha-1, potassium sulphate source). Results showed that application of N and K significantly increased plant height, leaf number, bulb diameter and length, and bulb fresh weight in both years. Increasing nitrogen concentration up to 100 kg ha-1 increased the phenols and flavonoids contents and antioxidant activity, but application of 150 kg ha-1 N caused a decrease in such parameters. Also, application of high level of K increased quality traits and antioxidant activity. Application of N and K fertilizers increased the content of them in bulb tissue in both years. According to the results, application of 150 kg ha-1 K and 100 kg ha-1 N could be recommended to improv grwth, bulb yield and antioxidant properties of sweet fennel.

Pollination is very important for achieving an economical production in hazelnuts. This study was conducted as a factorial randomized complete block design with three replications. In this study, the effects of three pollinizers (Pashmineh, Gercheh and Shastak) on nut and kernel characteristics of some hazelnut cultivars (Rounde, Fertilede coutard and Gerdeshkvarat) were investigated. The results of the flowering phenology showed that all cultivars were protanderious. The time of the male flowers opening in Ronde and Fertilede coutard was from early January to late January and in Gerd Eshkvarat was from mid-January to late January. The opening time of the female flower was variable from mid-January in Ronde to late February in Fertilede coutard. The results showed that the quantitative traits of nut and kernel were strongly influenced by pollen sources. Using stronger and more viable pollen grains of Gercheh pollinizer, the heaviest nut and kernels, the highest percentage of kernel production, and the lowest percentage of blankness kernels were 3.64, 1.48, 48.69, and 13.94, respectively. However, using Shastak pollen grains, the weight of the nut and kernel was decreased by 2.44 % and 1.22 %, respectively, and the blankness percentage of kernel was increased by 26.48 %. The amount of blankness increased dramatically to 87.51 % in self-pollination and nut and kernel weight significantly reduced to 1.27 and 0.22 g, respectively. In general, pollen grain had effects on some fruit characteristics such as nut and kernel weight, percentage of blankness and kernel production, and pollen grain had no significant effect on nut and kernel shape. The highest overlap of male flowers opening in pollenizer genotypes with female flowers of Rounde, Fertilede coutard, and Gerdeshkvarat was observed in Gercheh.

Correct pruning is one of the most important factors in growing plants particularly trees and shrubs, in the landscape. The present study was conducted to assess the effects of pruning intensity and nitrogenous fertilizer on physiological and morphological characteristics and wilting percentage in rosemary plant. A factorial experiment was arranged in a completely randomized design with five levels of pruning (no pruning, half of current –year branch prune, complete pruning of current-year branch, half one-year-old branch prune and complete pruning one-year old branch) and two levels of nitrogenous fertilizer (0 and 200 kg.ha-1) with three replications. For this purpose used 18-month-old rosemary cuttings grown in the greenhouse. Stem growth was measured during six months. Number of lateral branches, root and shoot fresh and dry weights, root volume and length, chlorophyll fluorescence, relative water content (RWC), ion leakage (EL) and proline were evaluated. The growth of rosemary plants was reduced with increased pruning intensity and fresh and dry weight of shoot and number of lateral shoots  were increased with useing nitrogenous fertilizer.With increased pruning intensity, RWC, ion leakage percentage and proline content were increased and chlorophyll fluorescence decreased. RWC and proline were increased with the application of nitrogenous fertilizer. The highest wilting percentage (77.77%) of plants was observed in complete pruning of one-year old branch with nitrogen fertilizer.

Tomato is one of the most important foods and economic crops in Iran and worldwide. Tomatoes require a lot of water to grow well and are adversely affected by drought. Considering the reports published on positive effects of seaweed extract on increasing resistance of plants to abiotic stresses, the present study aimed to evaluate the effects of a seaweed extract (Sargassum angustifolium) on growth and yield indices of tomato under drought stress. This study was conducted as a factorial experiment with three concentrations of algae extract (0, 0.5, 1 g L-1) and three levels of drought stress (control, 40% FC, 60% FC) plus a non-stress treatment with three replications. To evaluate the effects of algae extract on tomato under drought stress conditions, a combination of morphological and physiological characteristics including plant height, photosynthetic pigment content, lycopene content, phenolic compounds and antioxidant activities were measured. Results showed that treatment by seaweed extract significantly increased plant resistance to drought stress and significantly increased plant height and the content of chlorophyll, phenolics, lycopene, and proline content and significatly improved reactive oxygen species scavenging capacity and superoxide mismutase activity in  tomato. The best results of morphological and physiological traits were obtained using 1 g L-1 seaweed extract.

The meta-QTL analysis was performed to identify the most effective and stable QTLs related to quantitative traits in peach (Prunus persica). In the present study, a QTL database containing information of molecular markers in different peach populations was constructed. Then, a new genetic consensus map based on the Kosambi map function was created. A number of 137 QTLs from the initial pool were projected in the constructed genetic consensus map and eventually 22 meta-QTLs (MQTLs) on different linkage groups of the peach genome was detected. The linkage group 4 (LG4) had the highest number of MQTLs for the assessed traits. According to co-localization frequency analysis between existing QTLs in the detected MQTLs regions, blooming time had the highest co-localization (67%) with the QTLs of fruit weight. Pleiotropy or strong linkage between genes controlling blooming time and fruit weight could be explained for the co-localization of the tested traits. The MQTL.LG4.3 and MQTL.LG4.2 containing 14 and 10 QTLs in original genomic regions were identified as the most stable and reliable MQTLs controlling most of the traits tested in peach.

In order to assess the intra-cultivar genetic variation and the correlation between morphological traits of Akbari and Ahmadaghai cultivars of pistachio, 18 quantitative and 33 qualitative traits were measured and coded based on the pistachio descriptor. The results indicated that in this study, six main factors could contain 61.86 percent of the total variance. The fruit, nut, leaf, and terminal leaflet characteristics have constructed three main factor groups that compromise 76.60 percent of the total variance‏. These traits were the most important ones to separate chr('39')Akbarichr('39') and chr('39')Ahmadaghaichr('39') genotypes. Genotypes were divided into three groups based on six main factors. The first group contains the Ahmadaghai genotypes which significantly had the largest terminal leaflet width, fruit dimenstion (width and thickness), and nut thickness. The most genotypes of Akbari cultivar were located in the second group which is significantly different from other groups. These genotypes had the most fruit length and width. Also, the results showed that there was a wide variation in morphological traits of Akbari and Ahmadaghai cultivars which is due to provide of scions from trees that propagated from seed in the past.

The plantschr('39') ability to recover from stress conditions is different. Tolerant plants can recover faster and better after stress. This study was conducted to study the ability of recovery of hot- and sweet pepper under high temperature (40°C) based on a factorial experiment under the complete randomized design (CRD) at greenhouses conditions in vegetative and reproductive stages with 3 replicates. Proline, malondialdehyde (MAD), antioxidant, phenol, ion leakage, and hydrogen peroxide increased in both stages under heat stress. Proline and phenol were lower in the reproductive stage compared to the vegetative stage. The highest proline, antioxidant, and phenol contents were in sweet pepper whereas, MDA, hydrogen peroxide and, ion leakage in hot pepper under heat stress. Study the parameters in both stages showed that the vegetative stage was more tolerant to heat stress with increasing antioxidant, phenol, and proline contents in recovery time. Sweet pepper was more tolerant to heat stress with decreasing membrane destruction, increase antioxidant, proline, and phenol contents during recovering time after heat stress.

The extinction threatens some native orchids which has economic value. Artificial seed technology can prevent the extinction of these plants and can be suitable for producing and exporting of product. In this study, protocorms of Dactylorhiza umbrosa were encapsulated. The effects of three temperature treatments 4, 20, and 25°C were investigated during three periods 30, 60, and 90-days of artificial seed storage. Percentage of artificial seed germination during storage conditions, after storage, total percentage of germination and number of days required for germination incidence, were investigated. The highest germination percent during storage conditions was related to 90-days storage at 4 and 25 ° C, and the lowest obtained after 30 days at 4 ° C, which did not show any germination. The highest germination percentage of artificial seeds after storage and cultivation was observed in 60 days stored seeds at 4 °C. The highest total percentage of germination was obtained after 60 and 90 days storage at 20 and 4 °C, respectively. The highest number of days befor germination incidence was observed after 60 days of storage. The best treatment for storage of artificial seeds was 4 °C for 30 and 60 days, which showed the lowest percentage of germination during storage conditions and the highest percentage of germination after culturing.

Gotu kola (Centella asiatica L.) is one of the most valuable medicinal plants. Due to the reduction of surface water and the limitation of dispersion, the natural populations of this plant species are in extinction risk. The purpose of this experiment was to introduce a tissue culture protocol for rapid micropropagation of the Gotu kola plant. For callus induction, explants were established on Murashige and Skoog (MS) medium supplemented with different concentration of 6-benzylamino purine (BA) at six levels (0, 1, 2, 3, 4, and 5 mgL-1) and α-naphthaleneacetic acid (NAA) at four levels (0, 0.25, 0.5, and 1 mgL-1). The best callogenesis was obtained with maximum callus induction (83.33%), fresh weight (4.26 g), and daily growth rate (0.14 g/day) by combined application of 4 mg L-1 BA and 1 mg L-1 NAA. Different concentrations of BA (0, 1, 2, 3, 4 and 5 mgL-1) and NAA (0.1 mg L-1) were used for shoot regeneration. Combination of BA (4.0 mgL-1) with NAA (1.0 mgL-1) showed the highest shoot proliferation (74.99%), maximum number of shoots (7.66), petiole (6.66) and the longest shoots (1.56 cm). The effects of, IBA (0, 0.5, 1, 1.5, 2, 2.5 mgL-1) were examined on adventitious root formation. MS medium supplemented with IBA (1 mgL-1) showed the best percentage of rooting (84.66%), maximum number of roots Per plantlet (65), and the longest roots (3.33 cm) along with the highest percentage of survival (74.99%).

This study was conducted to investigate the effects of combined treatment of sodium alginate and ascorbic acid on the shelf life of strawberry fruits stored at 4±1 ° C. The treatments included control (distilled water), ascorbic acid (1%) with sodium alginate (1, 2 and 3%) and storage period for 7 and 14 days with 4 replicates. During storage, brightness index, chroma index, firmness, total acidity, vitamin C, phenol content, antioxidant activity and anthocyanin content were decreased, but the application of coatings preserved these indices as alginate 2% + ascorbic acid 1% was more effective to preserve these traits during storage. During storage period, polyphenol oxidase enzyme activity (50%), weight loss (2.8%) and pH (33%) increased. While the application of sodium alginate+ ascorbic acid preserved the lower levels of pH and the activity of polyphenol oxidize enzyme, it also controlled weight loss for 14 days.