SEED AND PLANT
Year:2023 | Volume:39 | Issue:2|Papers Count:6

Branding of commercial bread wheat cultivars for producing baking products with uniform and acceptable quality by cconsumers is related to sufficient knowledge of different environmental conditions of whaet growing areas in Iran, as well as baking quality properties of grain and dough. Therefore, the aim of this research wwas to investigate grain and dough rheological quality properties including quantity and quality of protein and gluten of the grain samples as well as farinograph and extensograph characteristics and grouping based on various products in the baking industry of 22 irrigated commercial bread wheat cultivars collected from 30 provinces in Iran in 2015-2016. The results showed that the highest and lowest grain protein content was recorded for cv. Mehregan and cv. Uroum with 12. 7% and 11. 4%, respectively. The wet gluten varied from 20. 5% (cv. Sisatan) to 30. 9% (cv. Gonbad), zeleny sedimentation value ranged from 18. 9 ml (cv. Arg) to 25. 5 ml (cv. Mehregan), and SDS sedimentation height varied from 51. 3 mm (cv. Sivand) 69. 6 mm (cv. Mehregan). The dough prepared from cv. Mehregan (15. 5 minutes), Soissons (10. 3 minutes) and Chamran 2 (10. 1 minutes) showed high dough stability, respectively. The lowest dough stability, among the examined cultivars, was related to cv. Uroum (1. 3 minutes) and Sistan (0. 2 minutes), respectively. Similar results were observed in extensograph test, cv. Mehregan and cv. Soissons were identified as semi-strong, while cv. Uroum, cv. Ehsan and cv. Heydari had the lowest dough energy. Finally, according to the results of this research some characteristics as growth habit, grain colour, grain hardness, grain protein content, farinograph and extensograph, the studied irrigated commercial bread wheat cultivars were grouped based on end-use products, in four groups, Voluminous breads (industrial breads) and suitable for blending with weaker flours, semi-voluminous breads, flat breads (Iranian breads) and confectionary, cakes, cookies and related industries. Introduction The definition of the word quality for agricultural commodity such as wheat includes different dimensions. In fact, the correct concept of quality for wheat is usually judged through its suitability for a specific product (Jasemi et al., 2017). One of the most important approches for evaluating the quality properties of wheat’s grain and flour is rheological characteristics of dough. The rheological properties of the dough not only determine the efficiency of the dough during different stages of fermentation and production process. Yang et al. (2014) investigated the rheological properties of the flour obtained from 330 of Chinese wheat varieties and reported that the rheological properties of dough had a high correlation with zeleny sedimentation value. Esmaielzadeh Moghadam et al. (2017) investigated the genetic diversity for high-and low-molecular weight glutenin subunits in local and commercial bread wheat cultivars released since 1951 in Iran and reported that integration of desirable subunits at Glu-1 such as 1, 7+8, 5+10, must be incorporated in breeding lines developed in the national bread wheat breeding programs which will lead to the improvement of gluten quality of grain. Therefore, the main objective of this research was grouping different irrigated commercial bread wheat cultivars grown in Iran based on end-ues products. Material and Methods This research was carried out in 2015-2016 cropping season using grain samples collected form certified multiplication fields of 22 irrigated commercial bread wheat cultivars in 30 different provinces in Iran. The reason for collection of grain samples from certified seed multiplication fields was to ensure that optimal agronomic practices was implemented by farmers in such fields. By collecting samples from the certified seed fields, the influence of soil fertility variation was minimized on grain of irrigated commercial bread wheat cultivars collected from each province. The collected samples were transferred to the cereal chemistry and technology laboratory of Seed and Plant Improvement Institute in Karaj, Iran. The evaluated quality properties included,grain protein content, grain hardness, wet gluten content, gluten index, zeleny value, SDS sedimentation height. Evaluate rheological properties included,farinography and extensography tests. Results and Discussion The results showed the highest and lowest grain protein content was measured and recorded for cv. Mehregan and cv. Uroum cultivars with 12. 7 and 11. 4%, respectively. The wet gluten varied from 20. 5% (cv. Sisatan) to 30. 9% (cv. Gonbad), zeleny sedimentation value ranged from 18. 9 ml (cv. Arg) to 25. 5 ml (cv. Mehregan), and SDS sedimentation height varied from 51. 3 mm (cv. Sivand) 69. 6 mm (cv. Mehregan). The dough prepared from cv. Mehregan (15. 5 minutes), Soissons (10. 3 minutes) and Chamran 2 (10. 1 minutes) had high dough stability, respectively. The lowest dough stability, among the examined cultivars, was related to cv. Uroum (1. 3 minutes) and Sistan (0. 2 minutes), respectively. Similar results were observed in extensograph test, cv. Mehregan and cv. Soissons were identified as semi-strong, while cv. Uroum, cv. Ehsan and cv. Heydari had the lowest dough energy. Rheological properties determined by farinography and extensography test showed that the relationship between grain protein content with dough extensibility and dough energy was strong and significant (r = 0. 52* and r = 0. 474*, respectively). Zeleny number had a positive and significant correlation with dough extensibility (r = 0. 477*) and dough energy (r = 0. 474*). According to the information reviewed from other countries and the results of this research and considering end-use products, some characteristics as growth habit, grain colour, grain hardness, grain protein content and rheological properties related to farinography and extensography were used for grouping of irrigated commercial bread wheat cultivars grown in Iran. Grouping of these irrigated bread wheat commercial cultivars in Iran based on important quality properties such as those studied and reported in this research will help the decision makers and managers of the agricultural sector as well as the experts of the flour and bakery industries to choose grain of right irrigated bread wheat cultivars.

Considering the extent of grapevine cultivation in arid and semi-arid areas of the world where salinity stress is one of the important environmental stresses that limits grape production in Iran. Therefore, this research was carried out for preliminary evaluation and comparison of the reaction of three grapevine native cutivars,Bidaneh Sefid, Bidaneh Ghermez, Shahroudi and three hybrids H4, H6 and Kober5BB rootstocks in response to salinity stress in Temperate Fruits Research Center, Horticultural Sciences Research Institute, in Karaj, Iran, in 2015-2017. The experiments were conducted as factorial arrangements in completely randomized design with five replications under in vitro conditions. The effect of salt was evaluated to identify the most tolerant cultivar/rootstock at four concentration levels of sodium chloride (NaCl),0 (control), 25, 50 and 75 mM. The results showed significant effect of different salt levels on grapevine cultivars/rootstocks for all vegetative traits including,length of shootlets, number of leaves shootlet-1 and leaf expansion. Most of these traits increased at mild salt stress up to 25 mM. However, at 50 and 75 mM, which are decisive concentrations for tolerance of plant tissues to salinity, the traits showed significant decreases. According to the vegetative growth charcteristics, H6 hybrid rootstock and cv. Shahroudi had relative tolerance to the salinity stress that was confirmed by high preservation of their chlorophyll content, as observed about 2 mg g-1 FW in H6 hybrid rootstock. The total protein and proline contents of leaves showed that the total protein content in all grapevine cultivars and rootstocks followed increasing trend with stress intensity. The proline content had an appropriate association with the higher tolerance level of H6 hybrid rootstock and cv. Shahroudi to 75 mM of sodium chloride. Introduction Salinity, as one of the abiotic stresses, affects the growth and production of agricultural crops by reducing the osmotic potential and creating osmotic stress, ion toxicity and nutritional imbalance in many regions of the world (Mahajan and Tuteja, 2005). Statistics show that about 1. 13 billion hectares of crop plants are affected by salinity-alkaline stress worldwide, which includes about 20% of the total cultivated area in the world (Morton et al., 2019). Grape is known as one of the horticultural crops with high economic value in the world, and its ecological scope for development is very wide. According to the Food and Agriculture Organization of United Nation (FAO), the grape production in 2020 was 78 million tons. The cultivated areas and grape production in Iran are about 230 thousand hectares and 2. 5 million tons, respectively, and stands 10th in ranking ladder in the world (FAO, 2020). The majority of grapevine cultivation is in arid or semi-arid areas where soil salinity and alkalization is a matter of serious concern due mainly to low rainfall and high evaporation, though different grapevine cultivars are relatively tolerant to salinity stress environments. This research was carried out with the aim of preliminary evaluation of the morphological characteristics and biochemical attributes contributing to resistance to salt stress of local cultivars and imported and rootstocks of grapevine under in vitro conditions. Materials and Methods Cultivars and rootstocks used in this research included three Iranian local grapevine cultivars,Shahroudi, Bidaneh Sefid and Bidaneh Ghermez and three rootstocks,two Iranian hybrid rootstocks, H4 (V. vinifera cv. Jighjigha × V. riparia cv. Gloire), H6 (V. vinifera cv. Gharaozum × Kober5BB), and one imported rootstock, Kober5BB (V. berlandieri × V. riparia). Applied salinity treatments were at four levels of sodium chloride,0 (control), 25, 50 and 75 mM. Modified MS culture medium (Murashige and Skoog, 1962) enriched with 0. 5 mg l-1 BAP was used to cultivate and establish explants. The experiment was conducted as factorial arrangements in completely randomized design with five replications. The most important traits that were evaluated included,shoot length, number of leaves, leaf area, proline and protein contents. Analysis of variance was performed using SAS software, and Duncan’s Multiple Range Test was used for mean comparisons at the 5% probability level. Graphs were made using Microsoft Excel Results and Discussion The tallest shootlet length was measured in the non-salinity stress conditions in cv. Bidaneh Sefid, cv. Shahroudi and H6 rootstock, respectively. Also, H4 and Kober5BB rootstocks had lower growth in non-stressed conditions compared with other cultivars and rootstocks. Mean comparison for the effect of salinity stress on morphological trait of leaf number at different levels of salinity stress,0, 25, 50 and 75 mM, similarly showed that, in the absence of salinity stress, the number of developed leaves shootlet-1 varied from 7 to 12 leaves in H4 and H6 hybrid rootstocks, respectively. The results of mean comparison for the effects of different salinity stress levels on leaf development showed that at 0 mM salinity level (control), a significant difference was observed between leaf expansion of cultivars and rootstocks. Normlly, leaf expansion under in vitro conditions is a function of the adaptability of genotype to tissue culture conditions as well as the type and level of growth regulators, the mode of use, and their interaction with internal plant hormones (Mansouryar et al., 2016). Mean comparison showed that with increases in salinity stress levels, the total chlorophyll content decreased in all studied cultivars and rootstocks. According to the results, at 75 mM salt stress in the culture medium, H6 hybrid rootstock, cv. Shahroudi, cv. Bidaneh Sefid and cv. Bidaneh Ghermez, Kober5BB rootstock as well as H4 hybrid rootstocks have the highest total chlorophyll content. In general, the results of this research showed that the in vitro evaluation on grapevine cultivars and rootstocks by increasing the level of sodium chloride (NaCl) with concentrations higher than 50 mM, which in this research 75 mM, as appropriate approach for preliminary evaluation and screening of cultivars and rootstocks for tolerance to salt stress. Threfore, it is necessary to examine several growth characteristics including,length of shootlets grown in in vitro, leaf expansion and number of leaves, over time after application of salt stress treatments. Biochemical characteristics, especially the rate of decay and reduction of total chlorophyll, should also be used as useful attribute for screening and selection of tolerant grapevine cultivars and rootstocks to salinity stress. Therefore, in the further researches, it is necessary to confirm these findings, in pot and orchard, conducting experiments in saline soil conditions.

Date palm is one of the important crops mainly grown in the arid regions of the Middle East and North Africa as well as in the southern warm and dry areas in Iran. One of the most important factors that reduces the quality and commercial value of date fruit is sunburn disorder during fruit growth and development. Therefore, this research was carried out to evaluate the effect of kraft paper, black, white, and blue cloth, green greenhouse netting, straw bag, and without bag (control) at the khalal stage on the ripening rate and sunburn incidence of cv. Medjool using randomized complete block design with eight replication in in Umm al Tameir research station, date palm and tropical fruits research, Ahvaz, in 2020 and 2021. The bags' ends were open and remained on the trees until harvest. The results showed that the bunch weight, the kimiri, khalal and date fruits proportions were affected by year. In 2021, average bunch weight (5. 83 kg), kimiri percentage (8. 6%) and khalal percentage (28%) were more than 2020, while in 2020 the percentage of date fruits (10. 48%) was more than 2021. The rate of kimiri at harvest was lower in black cloth than in others bags. In 2020, bunch bagging with green greenhouse netting, white cloth, and kraft paper increased rutab rate by 9. 81%, 12. 99% and 11. 37%, respectively, as compared to control. Bagging did not affect fruit size and weight. All kind of bags decreased the incidence of sunburn disorder. Kraft paper bag significantly decreased the percentage of dried fruits to 6. 78% as compared to control with 9. 93%. The rate of fruit decay was not affected by bagging. Considering the results of this research, it was concluded that black and white cloth bags were more effective in reducing sunburn disorder and fruit decay rate of palm date fruit cv. Medjool. Introduction Date palm (Phoenix dactylifera L. ) is a monocotyledonous species of the Arecaceae family widely grown in the arid regions of the Middle East and North Africa (Kordrostami et al., 2022). Recently, the production and cultivation of date cv. Medjool as the most popular and expensive date has attracted attention of consumers in many countries. Failure to ripe of some of the fruits is one of the most important reported problems of this palm date commercial cultivar, which reduces its marketable fruit yield and quality. In addition, the incidence of sunburn disorder decreases the quality of the fruit of date cv. Medjool. To prevent losses due to biotic and abiotic factors and to produce quality fruits with less dependency on chemicals, several good agricultural practices (GAP) have been examined around the world. Among these good practices, preharvest bagging of fruit has gained popularity as an effective method in different parts of the world (FAO, 2016). Bagging affects fruit maturity and ripening. There are conflicting results in literature in this regard. Harash and Al-Obeed (2010) reported that bagging bunches with black, white, blue, or yellow plastic bags accelerated fruits ripening of cv. Succary and cv. Khalas dates and stated that the blue color bags were more effective in accelerating the ripening of date fruits. Kahramanoglu and Usanmaz (2019) studied the effect of bagging on dates of cv. Medjool and found that bagging with black and porous polyethylene bags increased the fruit-ripening rate. It has been shown that bunche bagging can reduce the incidence of some disorders, so this method is widely used in some countries to reduce sunburn disorder and fruit cracking (Sharma, 2009). Therefore, this research was carried out to assess the effect of bunch bagging on ripening and prevention of sunburn disorder incidence in palm date fruits cv. Medjool. Materials and Methods This research was carried out to evaluate the effect of kraft paper, black, white, and blue cloth, green greenhouse netting, straw bag, and without bag (control) at the khalal stage on the ripening rate and sunburn incidence of cv. Medjool using randomized complete block design with eight replication in in Umm al Tameir research station, date palm and tropical fruits research, Ahvaz, in 2020 and 2021. The bags' ends were open and on the trees until harvest. After harvest, bunch weight, kimiri, khalal, rutab, and, tamar proportions, length, diameter, and weight of fruit, and rate of sunburn disorder and fruit decay as well as dried fruits were recorded. Combined analysis of variance was performed, based on randomized complete block design principles, using SAS 9. 4 software. Tukey test was employed for means comparison at the 5% probability level. Results and Discussion The results of this research showed that bunch weight, and proportions of kimiri, khalal, and tamar were affected by growing. In 2021, the average bunch weight (5. 83 kg), kimiri percentage (8. 6%), and khalal percentage (28%) were more than 2020 (3. 61 kg, 5. 36%, and 25. 27%, respectively), while the percentage of tamar in 2020 (44. 51%) was higher than in 2020 (34. 03%). This difference can be attributed to the difference in weather conditions during two growing season. In general, the weight of bunches covered with different bags was higher than control. The results are consistent with the results reported by Omar et al. (2014) regarding the increase in bunch weight with the application of bags. The proportion of kimiri at harvest time in kraft paper bags (10. 21%) was higher than in the other bags with the lowest in black cloth bags (4. 19%). In 2020, greenhouse netting (18. 38%), white cloth (21. 56%), and kraft paper (19. 94%) bags significantly increased in rutab percentage as compared with control (8. 57%). It can be stated that bagging (with the open-end bags) in this research did not affect fruit ripening rate of date cv. Medjool, and weather conditions were the main factor. Bagging did not affect fruit size and weight. In some countries, this method is widely used to reduce the sunburn disorder of date fruits. In this research, all kind of bags reduced the incidence of sunburn of fruits. In 2020, the proportion of dried fruits (14. 24%) was higher than in 2020 (4. 74%) and the kraft paper bag (6. 78%) significantly decreased as compared to control (9. 93%). The fruit decay rate was not affected by bagging. Considering the results of this research, it was concluded that black and white cloth bags were more effective in reducing sunburn disorder and fruit decay rate of date cv. Medjool.

Considering the adverse effect of changing climate, it is necssary to introduce new commercial high-yielding and marketable almond cultivars with different chilling and heat requirements, flowering time, which can adapt to various regions. Therefore, almond trees of three recently registered cultivars named,Aria, Bardia and Zeighami and two control cultivars grafted on bitter almond seedlings were compared using randomized complete block design with five replications from 2018-21 in an almond orchard in Neyriz of Fars province in Iran. Chilling and heat requirements, tree growth vigor, yield related traits, and relationships between different pomological and morphological characteristics were measured and evaluated. The results showed that cv. Aria was superior to the other cultivars due to its higher trunk cross-sectional area (TCSA) (325 cm2) and production and yield efficiency (100. 26 g nut and 25. 36 g kernel per cm2 TCSA). The proportion of double kernels and kernels in the Zeighami and Bardia cultivars, respectively, was below the standard classification for almonds. Cv. Aria and cv. Bardia had the lowest chilling requirements (296 CU) and cv. Ferraduel the highest (515 CU). The heat requirement of the newly registered almond cultivars was also lower than control cultivars. Aria and Bardia cultivars flowered two weeks earlier than control cultivars. In conclusion, cv. Aria is a suitable commercial almond cultivar for being grown in regions with no of spring frost risk. Introduction There is a need to introduce adapted temperate fruit trees to mitigate the adverse effects of climate change, especially in Iran. In addition, the improvement of genetic diversity in orchards through the identification and registration of new commercial cultivars of horticultural products is the most important platform for the protection of the germplasm of these valuable plants. Nowadays, almond breeding programs focus on the identification and introduction of high-yielding and marketable cultivars with low chilling requirements that can be adapted to regions with mild winters (Alonso Segura et al., 2005). Understanding the relationship between quantitative pomological and morphological traits with kernel yield and production efficiency is also important in almond breeding programs. This research aimed to evaluate morphological and pomological characteristics, tree growth vigor and yield of three recently registered and two commercial almond cultivars under environmental conditions of Neyriz of Fars province in Iran. Materials and Methods Three recently registered cultivars named,Aria, Bardia and Zeighami and two control cultivars,Ferraduel and Ferragnese, were studied in using randomized complete block design with five replications from 2018-21 in an almond orchard in Neyriz of Fars province in Iran. The chilling requirement was calculated using the Utah model as chilling unit (CU) as well as the Positive Utah model as positive chilling unit (PCU). Heat requirement was calculated as growing degree hours (GDH). Tree growth vigor at the end of the growing season was evaluated by measuring the circumference of the trunk at a height of 20 cm above the graft. The trunk cross-sectional area (TCSA) was calculated as an estimate of the tree growth vigor. Production efficiency (PE) was estimated as in-shell almond production normalized to TCSA. Yield efficiency (YE) was calculated as kernel production per tree normalized to TCSA. Kernel yield is the proportion of kernels by weight of the total nut. The cultivars were evaluated based on 46 morphological and pomological characteristics included in the UPOV Guidelines for the Distinctness, Uniformity and Stability (DUS) tests for Almond (Anonymous, 2019). The expression of quantitative characteristics were evaluated based on determined ranges (Giordani et al., 2016). The most important traits for grouping of the cultivars were identified using principal component analysis. Results and Discussion The results of this research showed the superiority of the recently registered almond cv. Aria as compared to check cultivars,Ferragnese and Ferraduel and two other newly registered cultivars,Bardia and Zeighami considering tree growth vigor (TV), production efficiency (PE), yield efficiency (YE) and kernel yield (KY) in the Neyriz region. Although the kernel weight (KW), yield and production efficiency of cv. Zeighami were high, double kernel (%) of over 60% was undesirable traits of this cultivar. The recently registered cv. Bardia also had kernel yield of less than 25%. The flowering time of the recently registered cultivars was about two weeks earlier than that of the check cultivars, although none of the studied almond cultivars suffered frost damage during flowering in 2018-21. Among almond cultivars with the highest (cv. Ferraduel) and the lowest cold requirement (cv. Aria), there was 15 days difference in the estimation of chill accumulation. The highest heat requirement was found for cv. Ferragnese and the lowest for cv. Aria and cv. Bardia. Based on the all studied traits, cv. Aria can be considered as suitable commercial almond cultivar for being grown in areas where there is no risk of spring frost (Alonso Segura et al., 2005). Principal component analysis of pomological, morphological traits and yield related traits resulted in four principal components, with only two principal components PC1 and PC2 accounting for 70% of the total observed variance. The most important traits of almond cultivars were,harvest time, resistance to nut cracking, foliage density, the degree of undulation of petal margins, the intensity of the brown color of the kernel, the time of beginning of flowering, the tree growth vigor, the length and width of the leaf blade, flower diameter, stone endocarp thickness, the tree growth habit, the degree of fruit pubescence, yield efficiency and production efficiency. Almond cultivars were classified in four groups using all traits on the two-dimensional diagram of two main components. In conclusion, cv. Aria is a suitable commercial almond cultivar for being grown in regions with no spring frost risk. The results of this research can be used for establishment of almond orchards in regions with similar environmental conditions as Neyriz of Fars province in Iran as we as in national almond breeding programs.

Dwarfing and nutrient uptake ability are among the important traits in pear rootstocks breeding programs. In this research, growth characteristics and macronutrients and iron uptake ability was compared in seedlings of 13 native and introduced species of genus pear (Pyrus), one commercial interspecies hybrid and three common clonal rootstocks of Pyrodwarf, Quince EMA and Quince BA29 from the species of genus Cynodonia (Cydonia oblonga Mill. ). Evaluation was carried-out under controlled conditions using completely randomized design with 10 replicates in 2022. Growth characteristics and chlorophyll index in 70, 120, and 160 days after establishment were evaluated and measured. Nitrogen, phosphorus, potassium and iron uptake was evaluated and compared in Pyrus and Cydonia rootstocks 160 days after seedlings establishment. The results showed that the highest dwarfing rate belonged to P. syriaca followed by the clonal rootstocks, and the highest growth rate was measured in seedling rootstocks of P. communis derived from cv. Dargazi followed by P. bretschneideri. In P. syriaca, the lowest internode length was observed after 160 days with an average of 1. 61 cm, which indicated the effect of dwarfing on slowing the growth of this species. Regarding the uptake of nutrient, P. hyrcana, P. nivalis, and P. pashia had the highest nitrogen uptake, P. amygdaliformis and P. nivalis had the highest phosphorus uptake and P. syriaca had the highest leaf potassium content. Considering the results of this research, future researches should focus on e evaluation of using P. syriaca as a dwarf rootstock for in establishment of intensive/ highly intensive pear orchards, or as the parent for dwarfing traits in pear breeding programs. Introduction Pear (Pyrus spp. ) is one of the oldest cultivated fruits in the world and some evidence show the cultivation of pear trees in the Neolithic era (Simionca Mărcășan et al., 2023). About 22 different species of the genus Pyrus have been identified in the world, of which about 12 species have been reported in Iran. The existence of different species of this genus in the plateau of Iran has contributed to the country as one of the main centers of diversity of pear species in the world (Abdollahi, 2010). Currently, the cultivated areas of pear orchards in the world is estimated to be about 1. 5 million hectares, from which about 24 million tons of fruits are harvested annually. According to the World Food and Agriculture Organization, China, USA, and Italy were the most important pear-producing countries in 2021 and Iran ranks 15th in the world (FAO, 2022). The rootstock of fruit trees plays a very important role in determining the efficiency and sustainability of orchards of different horticultural crops. In a standard and modern pear orchard, the trees should have uniform canopy, which facilitates husbandry operations and harvest as well as producing uniform and high-quality fruits (Roberto et al., 2022). One of the problems in the cultivation of pears in Iran is the lack of access to suitable and adapted rootstocks to Iran's different climatic conditions. European pear seedling rootstocks obtained from cv. Dargazi are used in the nurseries (Abdollahi, 2010). Considering the existence of germplasm of different pear species in Iran and the existence of different growth rates among different species, it is necessary to evaluate this germplasm for use in rootstock breeding programs. Also, the availability of different introduced species of the genus Pyrus from Southeast Asia in Iran facilitates evaluation and comparison of the growth vigor and characteristics of these species for further use in the national pear breeding programs. Vegetative growth and nutrients uptake potential has not been evaluated between seedlings obtained from many native and introduced species of the genus Pyrus and pear clonal rootstocks in Iran, Therefore, the present research aimed to evaluate and compare the vegetative growth and nutrient uptake in the seedlings obtained from different species of the genus Pyrus and commercial clonal rootstocks. Materials and Methods Growth characteristics and macronutrients and iron uptake ability was compared in seedlings of 13 native and introduced species of genus pear (Pyrus), one commercial interspecies hybrid and three common clonal rootstocks of Pyrodwarf, Quince EMA and Quince BA29 from the species of genus Cynodonia (Cydonia oblonga Mill. ). Evaluation was carried-out under controlled conditions using completely randomized design with 10 replicates in 2022. Growth characteristics and chlorophyll index in 70, 120, and 160 days were evaluated and measured. Nitrogen, phosphorus, potassium and iron uptakes was also measured in the two genera of Pyrus and Cydonia rootstocks, 160 days after establishment. Phosphorus, potassium, and total iron contents were measured using an inductively coupled plasma device (model Agilent Technologies, Varian 700-es ICP-OES, USA), and nitrogen content was determined using the Kjeldal and via the digestion method. Analysis of variance for data was performed using SAS 9. 2 software. Duncan’s Multiple Range Test was employed for means comparison at the 5% probability level. Results and Discussion Analysis of the variance showed significant difference between rootstocks for all vegetative traits. These significant differences were observed in all three developmental stages,70, 120, and 160 days after seedlings establishment. Pear species originated from Southeast Asia including,P. calleryana, P. betulifolia, and P. bretschneideri had the most vigorous vegetative growth as they reached 107. 20, 98. 80, and 132. 0 cm, respectively, after 120 days after establishment. On 160 days after establishment, Dargezi seedlings with 145. 6 cm had the tallest plant height and P. syriaca seedlings with 56. 10 cm had the shortest height, respectively. The results also showed that in 120 and 160 days after seedling establishment, chlorophyll index increased in most of rootstocks. In 70 days after establishment, chlorophyll index varied from 25. 66 to 62. 66. According to the reports, different pear cultivars have demonstrated good compatibility with P. syriaca species. P. syriaca is known as an excellent tolerant genotype to drought stress as well as calcareous soils. Therefore, this species has great potential for breeding of new dwarfing pear rootstocks in Iran. Regarding nutrient uptake ability, P. hyrcana, P. nivalis, and P. pashia had the highest nitrogen content, P. amygdaliformis and P. nivalis had the highest phosphorus and P. syriaca had the highest leaf potassium contents. Also, all species of the genus Pyrus had higher total iron content when compared to the rootstocks belonging to C. oblonga.

An increase in the temperature and frequent droughts are consequences of the climate change. Using different methods of producing horticultural products in protected ways, such as shading net, is one approach to mitigate the impact of the changing climate. The present study was carried out to determine the effect of shading net on growth and fruit yield and quality of four grapevine (Vitis vinifera) cultivars in the Takestan grapevine research station in 2022. For this purpose, vegetative and reproductive characteristics of four grapevine cultivars (Sahebi, Red Sultana, Red Asgari and Mish Pestan) were evaluated under and outside of green shading net with shade coefficient of 50% as factorial arrangements in randomized complete block design with three replications. Significant increase of internode length under the shading net were recorded. Green shading net significantly increased the titratable acid (80. 6%) and the pH of the fruit juice (73. 2%), the length and width, and the weight of berry (21. 8%, 44. 11%, and 41. 7%, respectively), cluster length, diameter and weight (51. 6%, 49%, and 30. 8%, respectively), and fruit yield per vine (65%). However, green shading net caused significant decrease in total soluble solids (17. 7%). In all grape cultivars, the total soluble solids under the green shading net was lower than outside the green shading net, and the highest total soluble solids (26 Brix units) belonged to cv. Red Sultana outside of the shading net. The titratable acidity (TA) level of fruit juice under shading net was higher than outside the shading net in all grape cultivars. The highest TA level (8. 5g l-1) was observed in cv. Mish Pestan under green shading net. The dimensions of berries under the shading net were greater than outside in all studied grape cultivars. The results showed that the fruit yield and its components increased under green shading net, but fruit ripening prolonged. Therefore, for table grape production, it is necessary to collect the shading net in fruit color changing period to prevent late ripening. Introduction Due to changing climate, the yield and the quality of agricultural products including grapevine are significantly affected. The intensity of sunlight and high temperature are especially important because of their effects on phenological stages, fruit yield, flower and berry drop, berry weight, and on the production and accumulation of primary and secondary compounds. Using Shading nets have been suggested in viticulture as an adaptation and protection approach to mitigate the effect of high temperatures (global warming) and decrease evapotranspiration (Naulleau et al., 2021). The present study was carried out to determine the effect of the green shading net on growth, fruit yield and its components and quality of four grapevine (Vitis vinifera) cultivars in the Takestan grapevine research station, Takestan, Iran. Materials and Methods Four grapevine cultivars (Sahebi, Red Sultana, Red Asgari and Mish Pestan) were evaluated under and outside of green shading net with shade coefficient of 50% as factorial arrangements in randomized complete block design with three replications and three vines in each plot. Cluster dimensions and weight, clusters number vine-1, dimensions and weight of berry, total soluble solids (TSS), pH and titratable acidity (TA) of fruit juice, fruit yield vine-1 and internode length were measured and recorded. SPSS Ver. 26 software was used to test the data normality, analysis of variance, and means comparison by Tukey's test at the 5% probability level. Factor analysis was performed based on principal component analysis and varimax rotation, as well as drawing graphs, using XLSTAT 2019 add-in under Excel software. Results and Discussion Using green shading net significantly increased (66. 2%) the internodes length. ​Green shading net significantly increased TA (80. 6%) and pH of fruit juice (73. 2%), but significantly decreased TSS (17. 7%). The highest amount of TSS (26 Brix units) was obtained in cv. Red Sultana outside of the shading net and the lowest (17. 9 Brix units) obtained in cv. Sahebi under the shading net. The highest amount of TA (8. 5 g l-1) was observed in cv. Mish Pestan under the green shading net and the lowest (1. 3 g l-1) in this cultivar in the outside of shading net. Serat and Kulkarni (2015) reported that the maximum TSS, total sugar, reducing sugars, non-reducing sugars and the ratio of TSS to TA in grape variety Thomson Seedless in without shading net environment (compared to green shading net with shade factor of 30% and 50%) were obtained. The reduction of heat stress due to the use of shading net has delayed the activation of VvHsfA2 and VvGolS1 factors, which causes a decrease in TSS and delay in fruit ripening (Pillet et al., 2012). Green shading net significantly increased the length, width, and weight of berries (21. 8%, 44. 11%, and 41. 7%, respectively), cluster length, diameter, and weight (51. 6%, 49%, and 30. 8%, respectively) and vine yield (65%). The highest berry length (2. 48 cm) was obtained in cv. Sahebi under the green shading net and the lowest (1. 07 cm) was obtained in cv. Red Sultana outside of the shading net. The highest berry weight (4. 25 g) was recorded in cv. Sahebir under the green shading net and the lowest (0. 77 g) was recorded in cv. Red Sultana outside of the shading net. Rasoli et al. (2022) reported that white and green shading nets, with shading factor of 30%, increased the cluster weight by 107. 2 and 141. 8%, respectively. The results of this research showed that using green shading net increased fruit yield and its components, and prolonged fruit ripening. Therefore, for table grape production, it is necessary to collect the shading net in color changing period to prevent late ripening.