مهدی حدادی نژاد

In order to determine the chilling and heat requirements of blackberry cultivars, three thorny (Tupi, Marion, Silvan) and thornless (Merton) cultivars were collected from the blackberry collection of Sari of Agricultural Sciences and Natural Resources University (SANRU) placed in the refrigerator. Treatments were included cultivars and chilling hours (300,500,700,900, 1100 and1300) in three replications and 10 samples. Then the floricanes were placed in the greenhouse under 16 hours of light and 24 ° C and the number of days to flowering of the first bud, the number of days to flowering of 50% of buds and the final percentage of bud breaks were recorded and the heat requirement was calculated. The results showed the highest rate of first bud burst occurred in the thorny cultivars of Silvan, Marion and Tupi in 700 hours of chilling and the cultivar thornless Merton in 500 hours of chilling. Among the thorny cultivars, two very early and late cultivars (Silvan and Marion) in 700 hours and late cultivar (Tupi) in 300 hours of chilling reached 50% full bloom earlier. While thornless Merton cultivar reached this level with 1100 hours of chilling. Examination of heat requirements of different cultivars showed in thorny cultivars, with increasing chilling hours, the need for heat decreases. So that all three cultivars of Silvan, Marion and Tupai in 300 hours of chilling, needed more heat, which has decreased with the increase of chilling hours until reaching 700 hours. In thornless Merton cultivar, from 300 hours of chilling to 700 hours, the need for heat has decreased, but after that, reaching 900 to 1300 hours of chilling, the need for heat has also increased. In general, thorny cultivars needed less chilling than thornless cultivars to open the first bud and achieve full flowering. Therefore, cultivation of thornless cultivars in areas with chilling units of less than 500 hours is difficult and requires additional treatments.

Strawberry is a herbaceous perennial plant that is mainly propagated using daughter plants obtained from runners in the form of bare roots from December to February from the nursery or propagation center. Typically, runners with larger crown diameters produce a higher number of flowers and consequently have higher yields. Proper nutrition is one of the factors affecting crown diameter. Nutrition during the induction of flowering period is very important for improving flowering. High nitrogen levels during summer may increase crown formation and generally increase production. In this research, application of different amounts of nitrogen fertilizer on mother plants during spring and fall seasons was carried out to determine its effect on the quantitative and qualitative traits of the produced runners. The research was conducted under field conditions in soil beds. Camarosa cultivar plantlets were obtained from a reputable nursery and planted in March 2017 with 40 cm spacing between plants in two rows on ridges in Ghaemshahr. The experiment was carried out as a factorial based on a completely randomized block design with spring fertilization at three levels (0, 150 and 300 kg/ha nitrogen) and fall fertilization also at three levels (0, 50 and 100 kg/ha nitrogen) with three replications (each replication containing 4 plants). Spring fertilization (S) was applied in three splits during March to April (March 30 to April 26) every week and fall fertilization (F) was also applied from Early to late September (September 7th to September 28th) in 2017 on mother plants every week. Then in late November, daughter plantlets were separated and planted separately based on each treatment. After planting the seedlings, no fertilization was applied in order to determine the effect of fertilization of mother plants on the growth and yield of produced plantlets. Subsequently, the fruits were harvested from early May and transferred to the laboratory. Then morphological, biochemical traits of the fruits as well as photosynthetic traits of the plants were evaluated. The results showed that nitrogen consumption of 150 kg/ha in spring and 100 kg/ha in fall resulted in the maximum fruit length of 3.91 cm. The use of fall fertilizer of 100 kg/ha has resulted in the highest fruit weight of 15.24 gr. Although this value was not significantly different from other high levels of nitrogen. The use of fall and spring fertilizer decreased the soluble solids and anthocyanin, so that the highest amount of soluble solids (8.47) was observed during the application of fall fertilizer and the time of application of spring fertilizer in the amount of 150 kg/ha, at the rate of 9.66. The amount of anthocyanin was at the highest level from the control treatment to the simultaneous application of 150 kg/ha in spring and 50 kg/ha in fall, and after that it was similar to soluble solids with a decrease. Excessive consumption of nitrogen fertilizer disrupts the balance of beneficial fruit compounds and increases fruit nitrate content. Increased over-consumption of nitrogen fertilizer leads to disruption of fruit compound balance such as vitamin C, anthocyanin, and other secondary metabolites. Fall nitrogen application had a more significant effect on increasing photosynthetic parameters and chlorophyll fluorescence including net photosynthesis and maximum quantum yield of photosystem II. Overall, the results showed that nitrogen fertilization has a very great impact on the production of strong plantlets. According to the obtained results, application of 100 kg/ha of nitrogen in fall can be recommended for production of healthy strawberry plantlets with high numbers.

Considering the abundant use of chemical fertilizers in agriculture and their detriments to the environment, it is necessary to consider alternatives to prevent possible damage.

A completely randomized factorial experiment with four replications was conducted in the Nur country to investigate the imapct of nitroxin and vermicompost on the qualitative and functional characteristics of Blackberry. The first factor was the percentage of vermicompost at five levels (0, 10, 20, 30 and 40% by volume) and the second factor consisted of inoculation and lack of inoculation with nitroxin (Ni).

The results demonstrated that the highest fruit weight, number of fruits, and yield were observed at 20% vermicompost. Maximum fruit length (1.62 cm) was obtained with 10% vermicompost and nitroxin inoculation. In analyzing the biochemical traits, the highest soluble solids and taste index were observed in the 10% vermicompost treatment. The largest amount of anthocyanin was obtained in the 20 and 30% vermicompost treatments at 551 and 563 (mg/L fruit juice), respectively. The application of nitroxin along with 30% vermicompost yielded  the highest amount of vitamin C among all treatments.

The application of vermicompost at 20 to 30% levels had the best impact on the quantitative and qualitative traits of Blackberry, and in cases where high amounts of vermicompost exerted a negative effect on some traits, nitroxin was able to reduce this effect and enhance certain traits. In this assay, the application of vermicompost at 20-30% along with nitroxin demonstrated the best impacts on blackberry traits.

In order to investigate the effect of drought stress on the enzymatic and non-enzymatic antioxidant system of six grape varieties, a factorial experiment was conducted based on a completely randomized design with three replications under greenhouse conditions. In this experiment, the treatments included six grape varieties (Asgari, Khalili, Yaquti, Pikami, Turkmen 4 and Suzak) and four levels of drought stress (normal conditions (100% of the farm capacity), low stress (75% of the farm capacity), medium stress (50% of the farm capacity) and severe stress treatment (25% of the farm capacity). The results showed that the traits of proline, malondialdehyde, catalase enzymes and ascorbate peroxidase enzymes improved with increasing stress intensity. increased significantly. On the other hand, the content of total phenol decreased significantly with the increase of the intensity of stress. Among the cultivars studied, Yaqouti cultivar is more resistant to drought than other grape cultivars in terms of the studied indices. The highest amount of catalase enzyme activity was recorded in Yaqouti cultivar, so that its catalase enzyme activity at the levels of 75, 50 and 25% of the agricultural capacity increased by 13, 12 and 46% respectively compared to the 100% agricultural capacity. According to the results of this research, it seems that Yaghuti cultivar is more drought tolerant than other cultivars. Since this toleration mechanisms located in leaf of Yaghuti, it is necessary to carry out additional tests when using as rootstock.

In order to investigate the effect of drought stress on the physiological and biochemical traits of six grape cultivars, a factorial experiment was conducted based on a completely randomized design with three replications under greenhouse conditions. In this experiment, the treatments included six Khorasani and shirazi grape varieties (Askari, Khalili, Yaquti, Pikami, Turkmen 4 and Suzak) and four levels of drought stress (normal conditions (100% of the farm capacity), low stress (75% of the farm capacity), medium stress ( 50% of farm capacity) and severe stress treatment (25% of farm capacity). The results showed that physiological and biochemical traits increased significantly with increasing stress intensity. On the other hand, the traits of relative leaf water content, membrane stability index, amount of photosynthetic pigments, and total phenol content decreased significantly with increasing stress intensity. Among the cultivars studied, the Yaqouti cultivar showed more resistance to drought than other grape cultivars in terms of the studied indices. According to the results of this research, it seems that Yaghuti cultivar is more drought tolerant than other cultivars. Since this tolerance located in leaf via active mechanisms, it is necessary to carry out additional tests when using Yaghuti as rootstock for scion of grapevine.

In order to determine the chilling and heat requirements of blackberry (Rubus sp.) cultivars, three thorny (Tupy, Marion, Silvan) and two thornless (Merton and Red immature) cultivars after the onset of dormancy and after exposing the chilling requirement were collected of the Blackberries collection from Sari Agricultural Sciences University (SANRU) and evaluated in a greenhouse via RCBD at three replication at 2019. Then the chilling and heat requirement models were calculated. Results showed differences in chilling requirements of thorny and thornless blackberry cultivars in field conditions. The highest percentage of the first bud burst related to thorny cultivar Silvan after 500 hours chilling. Marion and Tupy, and Red immature burst in 700 hours of chilling but Merton thornless burst after 900 hours. Also, the minimum day number for 50% bud burst in all cultivars was obtained in 700 hours of chilling. It should be noted that only thorny cultivars have reached full bloom and therefore are the most suitable cultivars for the development in eastern of south of Caspian Sea region. Thornless cultivars did not reach full bloom even after receiving 900 hours of chilling. The heat requirement required for 50% of buds to bloom varied from 6324 GDH in thornless Merton cultivar to 1116 GDH in Tupy cultivar. Using complementary treatments like as Hydrogen cyanamide to improve bud burst can be helpful.

Soil salinity is one of the major environmental stresses which reduces the growth and yield of crops by affecting wide spectra of physiological and biochemical processes in plants. In this study, effect of foliar application of melatonin levels (0 and 200 μM) under salt levls (0, 30, 60, 90 and 120 mM NaCl) on sour orange rootstock was investigated. The experiment was carried-out as factorial arrangements in completely randomized design with four replications in 2020-21 at the research farm of Sari Agricultural Sciences and Natural Resources University, Sari, Iran. The results showed that most of morphological and physiological characteristics were affected by salinity and foliar application of melatonin. Salinity × foliar application of melatonin interaction effect was significant on most of studied traits including leaf length, leaf width, flush number, flush length, root length, leaf moisture and dry matter contents of leaf, ion leakage, stomatal conductance, transpiration rate, of assimilation rate, vapor pressure deficit and photosynthetic quantum yield. Foliar application of melatonin increased leaf moisture content, flush number, assimilation rate, stomatal conductance and photosynthesis quantum yield, while leaf ion leakage decreased. The highest photosynthetic quantum yield was recorded in 200 µM melatonin and salinity free treatment. Foliar application of melatonin under salinity stress conditions improved most of the physiological parameters. Foliar application of melatonin at different salinity levels caused significant increases in length and width of flush leaves compared to the control. Overall, the results of this study showed that foliar application of melatonin reduced negative effects of salinity stress on growth and physiology of sour orange rootstock, therefore, it can be considered as an effective approach to mitigate the adverse effect of soil and water salinity on sour orange rootstock.

Blackberry is a plant of the genus Rubus and family Rosaceae, which due to its nutritional properties has role in human health. One way to increase nutritional properties is to use bio-organic fertilizers such as vermicompost and nitroxin. These fertilizers not only reduce the negative effects of chemical fertilizers, but also improve the growth and reproductive characteristics of blackberries.

To investigate the effect of nitroxin and vermicompost on the vegetative and reproductive characteristics of blackberry, a factorial study was performed in a completely randomized design at 5 levels of vermicompost (0, 10, 20, 30 and 40) and two levels of inoculation and non-inoculation of nitroxin in pots in Noor city. For this experiment, culture media were prepared by mixing different levels of vermicompost with the base soil in the pot. Then, the rooted and uniform seedlings were prepared and selected for use in the experiment and the roots of the plants were placed in nitroxin solution (ratio of 1 to 10 with water) for 10 minutes and then planted in pots.

The results showed that the highest number of buds (42.5 per plant), the number of clusters (5.5 per plant), fruit weight (3.37 grams per plant) and the shortest ripening period were produced in 20% volume of vermicompost. The highest weight of drupelets (0.10 grams) was obtained in 30% volume of vermicompost. In addition, the largest flower diameter (3.77 cm) was seen in nitroxin treatment with 30% vermicompost by volume. The highest internode length (5.65 cm), branch length (2.55 m) produced in nitroxin treatment alone. The highest internode length (5.65 cm), branch length (2.55 m) produced in nitroxin treatment alone. The largest number of nodes (67 per plant) belonged to nitroxin in combination with 20% vermicompost by volume treatment and the largest vegetative branch diameter (2.8 cm) and leaf surface (25.83 cm2) was obtained in vermicompost treatments of 20% and 10% by volume, respectively. The use of vermicompost at the level of 20 to 30 percent by volume can show the greatest effect on fruiting branches, while nitroxin alone or in combination with vermicompost had a greater effect on vegetative branches. Vermicompost improves the growing medium conditions by stimulating beneficial soil microorganisms and the stable supply of mineral elements, especially nitrogen and phosphorus. The physical and chemical properties of humic acid in vermicompost increase plant nitrogen accumulation by increasing nutrient storage capacity and growth regulatory hormones, and plant growth factors such as height, number of nodes, internode distance and leaf area will increase with increasing nitrogen. However, increasing the level of vermicompost increases the concentration of soluble salt, toxicity due to increasing the concentration of heavy elements and the presence of toxic compounds in the plant, which leads to reduced growth and yield. Under these conditions, the use of nitroxin modulates or neutralizes the harmful effects of abiotic stresses. Bio fertilizers that contain growth-promoting bacteria, in addition to providing part of the nutrients and their balanced absorption, increase the nutritional value of the fruit by preventing the imbalance between the plant's internal components.

The use of vermicompost at the level of 20 to 30 percent by volume can show the effect on fruiting branches, while nitroxin alone and together with vermicompost has a greater effect on vegetative branches.

The present research tries to investigate the effect of potassium silicate and mycorrhizal fungus on heat stress tolerance of strawberries and evaluate the possibility of increasing plant tolerance to heat at research greenhouse in Sari Agriculture and Natural Resources University at 2019. It is in a completely randomized factorial design with three factors including two levels of mycorrhizal fungi (presence and absence of mycorrhizal fungi), three levels of potassium silicate (0, 50 and 100 mg.l-1) spray in heat stress (25 and 41 °C) with three replications. The results show that application of potassium silicate reduces the Photosynthtic active radiation (PAR) damage in strawberry leaves, which PAR of leaves bottom reduce three folds in comparison to the control, when the PARtop is 1133 umol.m2.s-1. In contrast, treatment of the plant with potassium silicate in the presence of mycorrhiza prevented increases transpiration and stomatal conductivity for water cooling the leaves during heat stress. Inoculation of the roots with mycorrhiza fungi leads to a wide network of hyphae in root uptake, improving water use efficiency by up to 72%, which in turn results in increaseed net photosynthesis. However, heat stress increases minimum fluorescence and reduces maximal quantum efficiency of photosystem II. But the simultaneous application of mycorrhiza and potassium silicate is able to improve this index to a good level (0.76). Finally, it has been found that high temperature stress affects many photosynthetic factors of strawberry plant that the use of potassium silicate in combination with mycorrhizal fungus, despite their separate use, to a large extent prevents heat damage to different parts of the plant.

Blackberry is a temperate plant that can also be grown in the greenhouse for off-season fruit production as well as greater profit. This study is conducted as a factorial experiment in a completely randomized design with three replications as a pot inside the soil. The first factor has been the cultivar (early, intermediate, and late) and the second one is the nutrition program at six levels of NPK(N0P0K0(control), N0P0K0, N50P0K25, N50P0K50, N50P25K50, and N50P12.5K25 kg/ha), applied as fertigation. Results show that the use of nutrients release the highest amount of nitrogen and potassium in the late cultivar. The highest shoot length and chlorophyll index belong to N50P0K25 treatment. Furthermore, blackberry’s response to different ratios of nutrients for shoot fresh weight in different cultivars show a different trend; however, the highest shoot fresh weight occurs in late cultivar in both N50P0K0 and N50P0K50 treatments. Results also show that maximum yield in early and intermediate cultivars in N50P0K25 treatment and in treatment with phosphorus (N50P25K50) could be observed in the late cultivar. The highest amount of soluble solids in early cultivar and N50P0K25 treatment belong to 12.9 Brixo. In general, though the use of NPK nutrients is effective in most studied traits, the role of N and K in improving the vegetative and reproductive traits in blackberry has been especially tangible for the two early and intermediate cultivars.

Raspberry (Rubus idaeus L.) is most important small fruits in the world with a good color and taste. The potential for optimum off-season production under greenhouse conditions improved its commercial value. In-vitro tissue culture is one of the methods for large-scale and uniform propagation of raspberries, where the type and concentration of employed growth regulators are crucial to complement and accelerate growth. Therefore, the aim of this study was to investigate the effect of different concentrations of benzyladenine and indolebutyric acid on direct regeneration of the raspberry lateral bud.

Red raspberry bushes cv. September were used for this experiment. The experiment was carried out a factorial experiment in a completely randomized design with four replications and each replication with five explants at Sari University of Agricultural Sciences and Natural Resources. Uniform lateral bud explants after disinfection placed in culture medium containing benzyladenine at three levels of 0, 0.4 and 1 mg L-1 and indolebutyric acid at three levels of 0, 0.1 and 0.5 mg L-1 in controlled environmental conditions and finally traits such as leaf number, node number, root number, root length and ect as well as photosynthetic pigments were measured.

The results of this study showed that simultaneous use of different concentrations of benzyladenine and indolebutyric acid growth regulators in the culture medium of raspberry explants had a positive effect on a number of studied traits. The use of high concentrations of benzyladenine increased traits such as leaf number, number of node, number of internode, leaf length, lamina length. Also, the use of benzyladenine with high concentrations of indolebutyric acid increased explant size and petiole diameter. Examination of explant root length and number showed that increasing benzyl adenine concentration decreased these traits, but the use of indolebutyric acid at higher levels increased root length and number. Evaluation of the effect Results of benzyladenine and indolebutyric acid on photosynthetic pigments indicated that the increase of these regulators increased chlorophyll a, chlorophyll b and carotenoid in traeted explants.

In general, the use of benzyladenine plus indolebutyric acid was effective depending on the concentration used, was effective in improving the vegetative traits of the plantlets of the raspberry lateral bud explants, but indolebutyric acid alone only affected rooting at high concentrations. So that the use of indolebutyric acid increased root number and length at higher levels that suggesting a functional contrast between these two growth regulators. Investigating the effect results of benzyladenine and indolebutyric acid on photosynthetic pigments resolved the ambiguity of how enhancing these regulators led to synergized and improved explant size. It was observed that with increasing concentrations of these regulators, increased in important photosynthetic pigments such as chlorophyll a, chlorophyll b and carotenoid was obvious. Importantly, the tissue and organs of raspberries are more susceptible than black berry and respond to lower concentrations of this growth regulators.

In order to evaluate genetic diversity using phenotype and phytochemical properties of sweet violet (Viola odorata), 10 regions of Mazandaran and Golestan provinces were studied. Phytochemical traits such as phenol content, flavonoid, antioxidant capacity, chlorophyll a, chlorophyll b, total chlorophyll, and morphological characters of leaf size, petiole length, pedicel length, and root length were evaluated. Sari and Kosout genotypes had the highest chlorophyll b and total chlorophyll contents and the Sari ecotype had the highest flavonoid content. The highest level of antioxidant capacity was observed in Sari and Vari ecotypes. The ecotypes of Zanglab, Aq Cheshmeh, Tangeh Chehel Chai with lower height showed the highest total phenol contents. Results of morphological evaluation showed that ecotypes of Vari, Sar,i and kosout had the longest leaves and  ecotypes of Azni and Vari had the longest roots. Also, ecotypes of Vari, kosout, Tangeh Chehel Chai, and Zanglab had the highest petiole length and Tangeh Chehel Chai ecotype had the highest leaf number. Correlation of traits showed that leaf height, leaf width, petiole length, leaf number, leaf flavonoid, and leaf phenol contents of sweet violet decreased with increasing altitude. In general, Sari, Vari, and Kosoot ecotypes from Mazandaran province had superior genotypes for most of the traits that could be used for future breeding programs.

Drought stress has different effects on plant growth and metabolism and is one of the most important factors limiting the growth of grapes. In order to investigate the effect of drought stress on some morphological traits and gas exchanges, own-rooted Sultana cultivar and grafted on Rasheh grape and 1103-P rootstocks were selected. This research was conducted by factorial arrangement in completely randomized design with three levels of drought stress and four replications at 2015-2016. Drought stress was applied after plants growth. The time of plants arrival to medium and severe stress levels was determined by weighted-volumetric method. Membrane stability index (MSI), leaf relative water content (RWC), leaf area (LA), leaf mass area (LMA), specific leaf area (SLA), chlorophyll a, chlorophyll b, photosynthesis rate (A), stomatal conductance (gs) and transpiration rate (E) were measured. The results showed that drought stress significantly decreased MSI and RWC. LA and LMA showed a significant difference between two levels of stress treatments. Under stress conditions, the SLA values ​​of the non-grafted Sultana were significantly different. Chlorophyll a and chlorophyll, gs and E decreased significantly by increasing drought stress. The results of measured traits of this study indicated the positive effect of the rootstocks used on increasing the resistance of susceptible Sultana grapes to drought conditions compared to non-grafted ones. Based on the findings of this research, Iranian grape variety (Rasheh) as the rootstock, as well as the famous American rootstock (1103), showed good tolerance to drought stress.

Optimal management of environmental factors, especially sunlight, in the trellis type cultivation of raspberry is one of the ways to increase the yield and quality of the crop. In order to investigate the effect of planting distance and number of vegetative branches on photosynthetic parameters and yield of Thornless blackberry, a factorial randomized complete block experiment with 4 replications was conducted in the four-year-old commercial garden of blackberry, located in Sari. . Treatments were row spacing at two levels of 1.5 and 2.5 meters and the number of vegetative branches per plant at two levels of 4 and 6 branches. The results of mean comparison showed that the highest area of ​​five leaves (140.6 cm) was belonging to the planting distance of 2.5 m and four branches. The highest production of branches and plants was observed in planting distance of 2.5 m (1.74 and 8.65 kg), respectively. Fruits harvested from plants with planting distance of 1.5 m had the highest amount of total anthocyanins, antioxidant activity, fruit size and the highest rate of photosynthesis (with an average of 5.58 μmol /m2.s). Also, the lowest leaf temperature (32.5°C) was recorded in this treatment. According to the results of his study, by reducing the distance between the raspberry plants, reducing the leaf temperature leads to an increase in photosynthesis rate and potential yield per branch. Conversely, at greater planting intervals, an increase in the number of branches is necessary to compensate the density and thus increase the total yield per hectare.

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.

Black berries (Rubus fruticosis aggr.) with more than 700 species are from worldwide and Iran small fruits. In addition of its wild relatives, there are breeded thorny and thornless cultivars which are under cultivation in the south region of Caspian Sea.Using chemical fertilizers is fastest method to compensate plants requirement to nutritional elements. Based on literature review, application of NPK will change the length of primocane, number and length of auxillary buds and flower number of inflorescence in blackberry, its yield component and antioxidant chracteristics, positively. The goal of this research was to evaluate the effect of different levels of nitrogen, phosphorus and potassium on three thorny blackberry cultivars.

This experiment performed in pots at Quancet greenhouse as completely random design in factorial. First factor included cultivar with three levels (Slivan, Marion and Tupy as early, mid and late ripening, respectivly) and second factor as fertilization in six rates (N0P0K0،N50P0K0، N50P0K25، N50P0K50، N50P25K50 &N50P12.5K25) in three replications. The measured traits included fruit quantitative charactristics like as weight, length and diameter (size), fruit qualitative traits like as Brix and titrable acidity, druplet traits as weight and precent of druplet material, number and weight of seed and antioxidant traits of juice (Antioxidant activity from Diphenyl-2-picrylhydrazyl method, phenol, flavenoiid and vitamin C).

Results showed that early ripen cultivar included the highest fruit weight, TSS and seed dry weight of 5 fruits (7.8g, 12.9% and 0.598g, respectively) in N50P0K25 which resulted the highest fresh and dry weight in seeds of fruits for late ripening cultivar as 2.528 & 0.607g. The most titrable acidity observed in late ripen cultivar and N50P0K0 treatment. The maximum weight of druplet, highest druplet matter precent achieved in early and mid ripening cultivars for N50P0K25 treatment which have been resulted highest anthocyanin rate in mid and late ripen cultivars. In oxidant stop precent and phenol rate of late ripen cultivar was higher than others. The most vitamin C was observed in N50P25K50 tretment and increase in nutrient affected this parameter and other phytochemical traits like as anthocyanin, negatively.

In the traits whihc related to reproductive growth and fruit, early ripen cultivar showed effectiveness than others significantly. However, in nutritional value (antioxidant traits) late ripen cultivar was better. Treatment with N50P0K25 in early ripen cultivar improved TSS, druplet weight, druplet matter and taste in compare to other treatments, significantly. late ripen cultivar was better. Treatment with N50P0K25 in early ripen cultivar improved TSS, druplet weight, druplet matter and taste in compare to other treatments, significantly.

Each plant requires specific amount of heat units complete its growing season. In this study, the heat units of different phenological stages of three cultivars of black raspberry have been investigated. After maintaining the chilling requirement, the studied cultivars were transferred to the greenhouse. The cultivars; Silvan (early), Marion (medium) and Topai (late) spent 91, 109 and 118 days from planting to harvest in the greenhouse, respectively. The results showed that the heat requirements of different raspberry cultivars to complete the phonological stages are different from each other. Early black raspberries variety has a lower heat requirement of 43,000 Cumulative Degree Growth Hours (CGDH) and produce larger fruits than their parent medium maturing variety with a heat requirement 51,000 CGDH. Under the climatic conditions of Sari, early maturing cultivars showed the capability to produce fruit in a 91 days period, while the same variety cultivated in the greenhouse, produced the fruits 2 month earlier, which is important in off-season production. For the Topai cultivar, which differs from early and middle cultivars in most traits, the phenological stages were longer and the single fruit weight and stalk length were higher comparing to other cultivars. However, in this cultivar, the buds break occurred earlier than other cultivars, although the higher heat requirement from fruit formation to ripening i.e. 55000 CGDH led to later ripening of the crop. Further studies on bioclimatic requirement of other blackberry varieties for proper management decisions and improving the production is recommended.

Viola odorata contain compounds such as peptide, flavonoids, glycosides, alkaloids, saponins and tannins, which are used in the treatment of certain diseases, including cancer. Viola odorata grows in the north forests, and little research was done on domestication and identification of this plant. This study was designed to evaluate the effect of three altitude differences in sea level in Mazandaran province (sari (56m) to Azni (1035 m) above sea level) on quantitative and qualitative characteristics of Viola odorata. The morphological (area of leaf, leaf width, petiole length, pedicel length and root length) and biochemical (phenol content, total flavonoids, antioxidant capacity) traits studied in the region via completely random design. The results showed that plants accessions from Sari with lowest altitude, had the highest leaf length, number of leaves, stem length, leaf phenol, total phenol, total flavonoid and leaf antioxidant capacity. Interaction results between region and plants organ showed, the highest rate of phenol was in the leaf and flower of Sari accessions and the most flavonoids rate were in the flower of Sari accession and the leaf and flower of Kosoot accessions. In general, accessions collected from the Sari area have a relative superiority to other areas for cultivation.

Strawberry is one of the important small fruits worldwide because of its high economical value. Mazandaran is ranked second among Iran’s strawberry prodcing provinces with about 14581 tones of strawberry yearly. This research aimed to evaluate the effect of different silicon sources on the reproductive and vegetative growth of strawberry in an outdoor hydroponic system.

This experiment carried out in a factorial format with two factors consisting of growth media (double medium: 1 cocopeat + 1 perlite, and triple medium: 1 cocopeat + 1 perlite + 1 rice husk) and silicon spray (control, 50 mg/L Si from sodium silicate, 100 mg/L Si from sodium silicate, 50 mg/L Si from potassium silicate, 100 mg/L Si from potassium silicate). It was performed in Sari Agricultural Sciences and Natural Resources University at 2016. Different characteristics including silicon concentration in the leaf, aerial fresh and dry weight, leaf number, fresh and dry weight of crown, fresh and dry weight of root, yield, weight of single fruit, number of the produced fruits in each plant were evaluated.

Potassium silicate 100 increased silicon concentration of strawberry leaf significantly. Leaf number of the plant and aerial dry weight in triple medium were significantly higher than the double medium. High rate of potassium silicate in the triple medium caused lower crown diameter in comparison with potassium silicate 50 in the same medium. However, in the double medium, the potassium silicate 50 was the best treatment for crown diameter.  Both fresh and dry weight of strawberry roots were the highest in the double medium and potassium silicate 50 treatment. Single fruit weight was maximum in the double medium and potassium silicate 100, which was not significantly different from potassium silicate 100 in triple medium. Fruit dry matter in the double medium and potassium silicate 50 treatments was more than other treatments. Fruit size was affected by medium, so that fruit size in the double medium was more than the triple medium significantly.

Sodium toxicity in sodium silicate treatment, low rate of silicon in potassium silicate 50 treatment, and lack of rice husk in the double medium could all negatively affect different physiological aspects of strawberry growth; or at least, they hindered achieving positive results. In summary, it can be concluded that the double medium and potassium silicate 100 can be recommended for higher yield and big strawberry fruit, but the triple medium and potassium silicate are useful treatments for vegetative growth specially for more crown diameter and root growth.

Influx of Siberian cold air masses into the northern parts of Iran causes severe decrease in temperature, heavy snowfall and freezing of citrus every few years. Depending on the temperature drop, in some years only fruits and in some years, citrus trees suffer severe damage too. One of the sudden drops in temperature was in January 2007, when the temperature dropped from -7 degrees Celsius to -13 degrees Celsius. Consecutive damage to citrus trees and crops in the north of the country has caused citrus gardeners to despair of its economic viability and to refrain from rehabilitating destroyed orchards. The mechanisms of frost resistance and relative tolerance to cold in citrus include physiological adaptation and metabolic changes. These changes will lead to the production of various cellular osmolytes, the accumulation of soluble substances, changes in lipid metabolism (with an increase in unsaturated fatty acids), an increase in supercooling temperature, and ultimately an increase in plant resistance. The use of passive and active methods can also partially prevent frost damage or reduce the severity of the injury, but spraying with compounds that may provide physical protection of trees against freezing or spraying chemicals that reduce the freezing point of the cellular fluid by altering the concentration of the cell sap could be more promising.

Experimental factors include freezing temperatures at three levels (-5, -8 and -11° C) and spraying with two types of experimental material including carnauba wax in two concentrations of zero and four percent (manufactured by Orange Saft SL, Spain) and glycol potash in two concentrations of zero and 10% (prepared by Pooshesh sabze Company, Iran), carnauba + glycol potash (carnauba wax in 4% concentration and 10% glycol potash concentrate) and control (distilled water solution).

Electrolyte leakage is the uncontrolled leakage of organic ions from the cell membrane due to stress and damage to the membrane. The lowest electrolyte leakage was observed at -5° C and the highest one was at -8° C. As a messenger molecule, proline is effective in regulating mitochondrial activity, cell proliferation, and cell death. Proline also expresses certain genes that are essential for improving plant conditions under stress. Proline concentration increased with decreasing temperature but it decreased again at -8 ° C. Using carnauba wax at -5 ° C has reduced the concentration of total soluble sugars (66.92 micro g / g by weight) but did not significantly differ from the control treatment (83/23) and -11 ° C. Frost tolerance and frost resistance vary in different organs of citrus trees. Young shoots and twigs are very sensitive to cold and frost, so their tissues change color due to the cold. If the intensity of cold and frost increases, it will cause the shoots to dry out. freezing temperature has a significant effect on Shoot dying back, so that the highest dryness of the shoots was observed at -11 ° C (91.66%) and the lowest at -5° C (10.41%).  The highest percentage of leaf abscission was observed at -11 and the lowest with significant difference at -5° C. Symptoms of freezing such as leaf abscission and tree Shoot dying back are not seen up to -5 ° C but they are well visible at -8 ° C. Experimental treatments also failed to prevent shoots from drying out at -11° C.

Thomson navel orange young trees do not suffer much damage up to -5° C, but as the temperature decreases, the damage caused by frost increases in the form of leaf abscission and Shoot dying back of branches. Carnauba wax has a positive role in this experiment by preventing leaf abscission at -8 ° C, but glycol potash has a negative role by increasing leaf abscission and Shoot dying back. Increasing leaf potassium levels through potash glycol not only did not increase cold resistance but also increased susceptibility to frost. Potassium must be supplied from other sources. The results of this experiment showed that the use of carnauba wax up to 48 hours before the possible cold, which is announced through meteorology, with a concentration of 4%, can keep it alive up to -8 ° C, which normally destroys the plant, but with passing through this temperature, for example at -11 degrees Celsius, is not able to maintain the plant.

Strawberry as a model plant in horticulture included many cultivars with special climatic and nutritional requirements. ‘Camarosa’ is the most cultivated cultivar in Mazandaran province, and the efforts of strawberry growers to alternate this cultivar with ‘Gaviota’ were not successful. The purpose of this research was to evaluation and comparison of characteristics of Camarosa and Gaviota in soil and soilless cultures to find the causes of unsuccessful culture of Gaviota in Mazandran Province.

Two separated experiments performed synchronously in open filed soil and soilless cultures with Camarosa and Gaviota cultivars in complete random design with three replications. Vegetative characteristic, yield and nutritional elements in rhizosphere and leaves were evaluated. Results

In soilless culture the differences of Camarosa and Gaviota cultivars was not significant except for fresh weight and volume of the root system. Average of root volume and fresh weight of Camarosa 19.5 cm3 and 13.7 g, were higher than Gaviota with 14 cm3 and 6.96 g, respectively. However, in soil culture almost all of the traits were significantly higher in Camarosa than Gaviota. Results of nutrition concentration analysis in rhizosphere showed the rate of Zn and Cu were exposed to maximum range of nutrient elements due to over-consumption of chemical fertilizers in strawberry fields in north of Iran and purpose the negative effects of elements as most important cause in unsuccessful soil culture of Gaviota in Mazandaran province. Although hen fertilizers added to soil in high volume (40 tonHa-1) annually and resulted too high percent of N, in soil (16%) it was not related to increase leaf N of plants and N concentration of leaves were lower than optimum range (3-4%). Potassium absorption efficiency in Gaviota was more than Camarosa but it seems that sensitivity of Gaviota to Cu toxicity is higher than Camarosa as well.

The cultivars Camarosa and Gaviota did not show significant difference in many traits in open field soilless culture so it seems that the lack of success in soil culture of Gaviota is not associated to climate conditions. The underlying problem of Gaviota is related to soil and nutrition aspects like Cu toxicity. To success culture of Gaviota in Mazandran Province, it is recommended to perform perfect nutrition management in soil culture or using soilless medium.

In order to study the effects of drought stress on polyphenolic compounds of pomegranate juice (Punica granatum L.) (total phenol, total flavonoid and cyanidin 3-glocoside content) as well as  fruit yield, an experiment was carried out as split plot based on a randomized complete block design with three replications (irrigation levels in main plots and pomegranate genotypes in subplots). Results showed that drought stress increased the content of juice polyphenolic compounds (P <0.05) and decreased fruit yield (P <0.05) in comparison with non-stress conditions (75±5% FC). However, mild stress (55±5% FC) caused a lower yield loss (P <0.05) compared to severe stress (35±5% FC). The results also showed that the genotypes studied could be considered as a rich source of phenolic compounds; however, the highest difference among the genotypes was found for cyanidin 3-glocoside content at different irrigation levels. On the other hand, based on the principal component analysis, under non-stress and mild stress conditions, genotypes Agha Mohamad Ali (AMA), Pust Sefid Torsh (PST), Malas Torshe Saveh (MTS), and Malas Shirine Saveh (MSS) could be recommended in food and pharmaceutical industries as superior and natural antioxidant-rich genotypes due to the high fruit yield and polyphenolic compounds. Generally, because of the importance of yield potential under drought stress, the mild drought stress treatment (55±5% FC) could be introduced as the optimum condition to obtain acceptable level of secondary metabolites, particularly cyanidin 3-glocoside, and fruit yield in Saveh region.

This research was conducted to identify the educational and extensional needs of strawberry growers in Mazandaran province. The statistical population consisted of strawberry growers in five counties of Mazandaran province (with more than 70% of the province's production, N = 3000), 240 of them were selected by Cochran's formula and multi stage random sampling technique. Data was collected through a questionnaire that its validity was confirmed by faculty members of agricultural extension & education and horticulture departments in Sari Agricultural Sciences & Natural Resources University and Agricultural Sciences & Natural Resources University of Khuzestan, also calculating Ordinal Theta revealed the suitable reliability of measuring instrument (range 0.78 to 0.86). Mean, standard deviation and spearman correlation, were used for data analysis and prioritization of needs as well as inferential statistics: mean rank comparison and ordinal regression. The results of study showed that three educational needs: stress tolerance, fruit quantity and fruit quality ranked first to third in importance. In tolerance to stress dimension, the resistance of the plant to winter cold and plant resistance to disease and pests were in the first and second priorities. In total, from 55 studied needs, fruit firmness in transfer was the most significant item. Based on Spearman’ correlation test, the variables of agricultural experience, education, income and daily work hours had significant relationship with the educational & extensional needs. According to ordinal regression results and Nagelkerke coefficient, these four variables can predict 59.7% of the changes in the educational and extensional needs of strawberries growers.

Persian walnut (Juglans regia L.) is one of the most important nut fruit of the world with high nutritional value. In order to produce a product with national standards, a step must be taken toward grafting walnut seedlings with a specified cultivar.  On the other hand, lack of suitable cultivars and ascending demand on grafted walnut seedlings will require a high production rate with short period supply. The epicotyl grafting is the fastest method of producing grafted seedlings in the propagation of some fruit trees such as walnut. In this method, the grafted, despite its high efficiency, results in high losses when the seedlings are transferred out of the greenhouse. The experiment was performed due to increase the survival rate of chandler grafted seedlings by using two types of cleft and omega cutting type, along with three types of moisture covers including: perlite, cocopeat, and sawdust.  The results showed that cleft cutting with an average graft success of 72.21%, performed better than omega cutting (8.33%) in epicotyl grafting. Perlite (93.32%) and sawdust (73.32%) had the highest graft success. Cocopeat by 50% of graft success caused root decay due to excessive moisture retention. The highest length of new growth branches with an average of 7.32 cm and a diameter of 3.93 mm was recorded 100 days after grafting in cleft grafting by perlite cover treatment.