جستجوی مقالات مرتبط با کلیدواژه "fruit yield" در نشریات گروه "باغبانی"

Pepper is a rich source of essential vitamins and minerals. Like tomatoes, pepper plays an important role in preventing heart diseases due to its high amount of antioxidants. Fruit yield is a complex trait that is not only controlled by several genes, but also greatly influenced by the environment. On the other hand, fruit yield is affected by a large number of other traits and their interaction. Therefore, it is very important for plant breeders to know the relationships between these traits and their interaction effects. The path coefficient analysis is a method that clarifies the relationships between traits and their direct and indirect effects on fruit yield. In this method, the correlation coefficient between two attributes is divided into components that measure direct and indirect effects. Considering the limited studies regarding the evaluation of relationships between fruit yield and other traits affecting fruit yield in pepper, this research was conducted with the aim of identifying these important relationships and evaluating their direct and indirect effects in Iranian pepper populations.
 
In order to carry out this research, the seeds of 30 Iranian pepper accessions were collected directly from the farmers. The experiment was conducted in the form of pot cultivation in the research greenhouse of the Faculty of Agriculture of Urmia University in a completely randomized design with five replications during 2015-2016. After the flowering stage, the desired traits were estimated. Variance analysis was estimated, after examining the basic hypotheses of variance analysis by SAS9.4, as well as the genotypic and phenotypic correlation between traits based on the restricted maximum likelihood (REML) procedure in the SAS9.4 software. Step-by-step regression analysis was used to determine the traits with the most variation justified the fruit yield. The Durbin-Watson test was performed to investigate the independence of experimental errors. Analysis of path coefficients was performed based on the results of stepwise regression and genotypic correlation of traits in the R V.4.0.5.
 
In order to understand the relationships between traits and use them in breeding programs, the phenotypic correlation was estimated.  In this study based on the results of phenotypic correlation, leaf width and leaf length (0.651), single fruit weight and fruit circumference (0.784), fruit circumference and fruit diameter (0.625) and pulp weight and fruit diameter (0.610), showed positive and significant correlation. The purpose of estimating genotypic correlation coefficient is to determine relationships in conditions which in environmental factors are not involved. In the investigation of genotypic correlation, a positive, strong and significant relationship between fruit yield and pulp weight (0.907), fruit circumference (0.891), fruit diameter (0.697), single fruit weight (0.646) and around the plant (0.381) were observed. Given that most of these traits are factors contributing to fruit yield, the presence of such positive and significant genotypic correlation coefficients is reasonable. It can be inferred that pepper accessions with higher fruit characteristics, encompassing factors such as plant density and branching, are likely to exhibit higher fruit yields as well. It's important to note that correlation coefficients are mathematical tools used to measure the linear relationship between two variables. Their significance lies in their mathematical interpretation, and as such, they alone do not provide sufficient proof of a cause-and-effect relationship. Utilizing the results of stepwise regression, less impactful traits or those with minimal effects were eliminated from the model. As a result, seven key traits were identified as the most influential factors affecting fruit yield: pulp weight, plant density, fruit diameter, fruit count, plant height, total seed weight, and branch count.The first characteristic was pulp weight, which was included in the model and explained 78.8% of the fruit yield changes between genotypes. The second characteristic (around the plant) along with pulp weight explained 80.9% of the fruit yield variations. Fruit diameter, together with the previous two characteristics, explained 81.5% of fruit yield variations. In total, the traits included in the model for fruit yield justified 84.6% of the total changes in fruit yield in 30 pepper accessions. In order to better understanding and more accurately interpret of the results, as well as to know the direct and indirect effects and the effect of the traits that were entered into the model through stepwise regression, the path coefficient analysis method was used in this research. Fruit diameter (0.709) and pulp weight (0.289) respectively showed the most positive and direct effect on fruit yield. Fruit pulp weight through fruit diameter had the most positive indirect effect (0.595) on fruit yield. Around the plant showed an indirect positive effect on fruit yield through pulp weight (0.157), fruit diameter (0.392) and number of branches (0.080).
 
In the present study, the trait of fruit diameter had a positive, strong and significant genotypic correlation (0.697) with fruit yield, and it also showed a positive direct effect (0.709) on fruit yield, these two coefficients can be considered equal, Approximately. Therefore, direct selection based on fruit diameter proves to be a valuable strategy for enhancing fruit yield. The magnitude of residual effects serves as an indicator of the model's accuracy in path analysis. When this value is substantial, it may be advisable to incorporate additional causal variables into the model. In the current study, the residual effects value (0.213) affirms the model's optimal accuracy.This research highlights the effectiveness of employing stepwise multivariate regression and path coefficient analysis to gain a deeper understanding of the fundamental relationships between traits. It underscores that relying solely on correlation relationships is insufficient for comprehensively justifying the associations between these traits.

Introduction: 

To specify the diversity of pepper plant (Capsicum ssp.) population and the inheritance of fruit characteristics for use in seed production breeding programs, there is a need for a diverse population in terms of the characteristics affecting fruit yield. By a large variety of options available for each product, there is a greater probability of selecting the best decision. A population's genetic variety may be used in several ways, including selection and hybridization. Pepper is a plant belonging to the genus Capsicum and the family Solanaceae. It is cultivated globally, particularly in tropical and subtropical regions. The genus Capsicum contains more than 30 wild and domestic species, which are classified according to flower structure, fruit, and the number of chromosomes (2n= 24, 26). 

Materials and Methods:

 To compare different pepper species based on fruit morphology, a greenhouse experiment was conducted under hydroponic conditions in Zarandieh region, Markazi province, in a completely randomized design with three repetitions in 2021. The seeds of 42 pepper genotypes from 7 species were obtained from Gene Bank of Leibniz Institute of Plant Genetics and Crop Plant Research (IPK). Initially, the seeds were sown in dedicated planting trays. Once the seedlings had grown six leaves, they were transplanted to the main greenhouse. Within the greenhouse, the rows of cultivation were spaced 160 cm apart, with a 25 cm gap between individual plants. Each genotype was represented by ten plants. Throughout the growing season, the plants were managed by maintaining two branches and removing any surplus ones. In this research, the following characteristics were evaluated: fruit production across three harvests, fruit weight, fruit length and diameter, fruit flesh thickness, fruit flavor (spicy or sweet), unripe fruit color, and ripe fruit color. Descriptive statistics of evaluated trait, including mean, minimum and maximum traits and the percentage of phenotypic and genotypic diversity coefficients, heritability, and the analysis of variance and comparison of means, were used to analyze the data.  

Results and Discussion:

 A diverse collection of pepper was evaluated due to the fruit morphological traits and significant differences among different genotypes in terms of these traits. The average fruit weight of the assessed population was 26.54 g. The minimum and maximum fruit weights of 152.70 and 0.13 g were related to genotypes 409 and 276, respectively. Genotype 318, with an average weight of 144.20 g, was not significantly different from genotype 409. Both genotypes were of the species annuum, but were in two separate groups regarding fruit morphology. The heritability rate of fruit weight was 93%, which is consistent with the results of Usman et al. (2014). Length, diameter and length to diameter ratio (fruit morphology index) are the most important factors in marketing pepper fruit. The mean fruit length, diameter and morphology index were 6.35, 2.57 cm and 3.04, respectively. The highest fruit length was related to genotypes 296 and 318 at 26.33, 20.20 and 19 cm, while the lowest fruit length was 0.70, related to genotype 277. The genotypes with the highest lengths were long pepper and Kapia sweet pepper, respectively, and the genotypes with the shortest lengths tasted spicy. Genotypes 409, 200, 318, 326, 272 and 348 had the largest diameter with 6.50, 6.23, 5.80, 5.67, 5.60 and 5.30 cm, respectively. These genotypes are bell, round, Kapia, triangular, triangular, round and sweet in terms of morphology. The smallest fruit diameter belonged to genotype 293 (0.30 cm), and the nineteen genotypes with a diameter of less than 2 cm did not differ significantly from 293. Twenty genotypes with the smallest fruit diameter have a pungent flavor (Table 1). The range of the fruit morphology index was from 0.56 to 8.99. The lowest and highest values were associated with genotypes 342 and 296, respectively (Table 3). The fruit of genotype 296 was sweet, whereas the fruit of genotype 342 was spicy. The heritability of length, diameter and fruit morphology index were 0.97, 0.97 and 0.98%, respectively. The lowest and highest numbers of fruits per plant in each hand-harvest were 1 and 67 fruits, respectively, belonging to genotypes 342 and 326. However, regarding shallow length, diameter, pulp thickness and, consequently, the low weight of the fruit in genotype 342, an almost low yield of this genotype was obtained in three harvests (2742.67 kg/ha). In contrast, genotype 318, despite its small number of fruits per hand-harvest (3 fruits per hand-harvest), had the highest fruit yield of 25379.20 kg Per hectare due to having fruits with large size and pulp thickness and as a result of high fruit weight. The lowest yields related to genotypes 276 and 293 belonged to C. frutescens L., with fruit yields of 17.60 and 44.00 kg/ha in three harvests. However, there was no statistically significant difference among the performance of these genotypes and the genotypes 277, 210, 282, 358, 261, 332, 394, 304, 311, 407, 321, 215, 427, 203, 342 and 200. The percentage of phenotypic and genetic variations in fruit yield was 61, 55% and the heritability of fruit yield was 81%.

This study evaluated a diverse collection of different species of pepper with a wide range of appearance traits. However, the most desirable and marketable characteristics of the fruit were obtained from genotypes belonging to C. annuum. However, genotypes belonging to other species, which were not addressed due to the high number of fruits per plant and resistance to pests and diseases, can play a complementary role in hybrid seed production breeding programs. Based on the results, genotypes 318 (Kapia, yellow and sweet), 287 (long, red and spicy), 348 (round, red and sweet), 272 (triangular, red and sweet), 309 (black, red and sweet) and 296 (long, red and sweet) could be introduced as cultivars after evaluating their compatibility, in terms of their high yield, suitable size fruits and marketability. In addition, because to the substantial variety of the examined population, breeding efforts might develop hybrid cultivars with unique traits.

 Grape (Vitis vinifera L.) is one of the most important fruits cultivated in many areas with different climates all over the world. Grape, which is rich in antioxidants, flavonoids, anthocyanins and phenolic acids, is highly regarded in terms of economic value. Salicylic acid is one of the compounds which have been used in recent years for improving the physicochemical properties of many fruits. The application of salicylic acid increases the shelf life of crops by inhibiting ethylene production and respiration, as well as by reducing the activity of some enzymes which are responsible for softening the cell wall. Furthermore, salicylic acid results in the enhancement of phenolic compound production by increasing the activity of some enzymes such as phenylalanine ammonia-lyase.

Materials and Methods:

 The present study was conducted in 2014 on 13-year-old Shahroodi grapes that were grown using a head-training system with a spacing of 2m × 2m in "Shahrood" County, Semnan Province. A total of 60 grapevines with uniform age and growth characteristics were selected for the experiment. Salicylic acid was obtained from Merck and solutions were prepared using a small amount of organic solvent and surfactant to reduce the surface tension of the solutions. For the purpose, the Salicylic acid powder was dissolved in a few drops of ethanol and a few drops of Tween 20 for improving solution penetration to the plants, The solution was prepared at concentrations of 0 (control), 1, 2, 3 mM. Then the plants were sprayed two weeks after the fruit set stage (when berries were at the pea-sized stage with a diameter of 4 to 5 mm). The experimental design used in this experiment was a randomized complete block design (RCBD) with three replications. After harvesting and transporting of fruits to the laboratory, different characteristics were measured:
Chlorophyll and carotenoid Content
Chlorophyll a, b, and total Chlorophyll and carotenoid content measured according to Arnon (1967) method in grape leaves. The extraction steps were carried out with full precision to minimize contact with heat and light. In order to stabilize the pigments, the samples taken from the central part of the mature leaves were immediately ground in liquid nitrogen. The samples were vortexed two times with an interval of one minute and stored for 1.5 hours at a temperature of 4 degrees Celsius in order to dissolve the pigments in cold acetone solvent. After that, they were centrifuged for 15 minutes at a speed of 6000 rpm. The supernatant after centrifugation of the samples was used to measure chlorophyll and total carotenoids. The absorbance of the samples was read at three wavelengths of 470, 645, and 663 nm using a Shimadzu UV (160) spectrophotometer. Using the absorbance of the samples in these three wavelengths and the equations below, the amounts of chlorophyll a, chlorophyll b, total chlorophyll and total carotenoids were calculated in terms of milligrams per gram of tissue sample weight.
Fruit characteristics
 Fruit characteristics such as fruit yield, fruit firmness (with magnets-Taylor device),  sugar and acid content, and content of phenolic compounds were also measured. The fruit tissue firmness was measured using a firmness tester (model FDKA 32, Wagner) and expressed in Newtons per square centimeter. The characteristics of soluble solids (TSS) were expressed using a handheld refractometer (Ataga, Japan) and expressed in terms of Brix, the pH of the extract was measured using a digital pH meter (Sartorius PP-20, Germany). Titratable acidity or TA was done through the titration of the extract using 0.1 normal sodium until pH 1.8-2.8 and its results were reported using the following formula and under the title of tartaric acid percentage.
Total phenol content
 The amount of total phenol was measured by Folin-Ciocalteu method and spectrophotometry. The absorbance of the reaction mixture was measured after 120 minutes of storage in the absence of light at a wavelength of 765 nm using a Shimadzu UV spectrophotometer (160). The amount of total phenol was expressed from the standard curve in terms of mg of gallic acid per 100 grams of extract in three replicates for each sample and standard.
Total flavonoid
 The amount of total flavonoid was measured by aluminum chloride calorimetric method. In this experiment, 50 microliters of methanolic extract from the flesh and fruit skin were combined with 10 microliters of 10% aluminum chloride and 10 microliters of 1 M potassium acetate. Then, 280 microliters of double distilled water were added to the mixture. After the samples were mixed, they were left at room temperature for 40 minutes. The absorbance of the reaction mixture was measured at a wavelength of 415 nm using a Shimadzu UV spectrophotometer (160) in three replicates. A blank containing double distilled water was used for comparison. The amount of total flavonoids was determined based on the standard curve of quercetin and the results were expressed in micrograms of quercetin per gram of fruit skin and flesh weight.
Total anthocyanin
 The amount of total anthocyanin was measured using the difference in pH method. In this method, the absorbance was measured using a spectrophotometer at wavelengths of 520 and 700 nm along with potassium chloride and sodium acetate buffers with different pH values of 1 and 4.5.

 The results of the data analysis of variance showed that the application of salicylic acid resulted in significant differences in the measured characteristics. Therefore, the use of this compound improved the physical and biochemical quality of the treated grape clusters.Comparison of treatments means showed that using 2 mM salicylic acid brought about a significant effect on the amount of chlorophyll (a, b and total) and carotenoids compared to other treatments, especially control. Salicylic acid application caused a reduction in pH and soluble solids, and an increase in firmness, 100-berry weight and yield. The results of the study indicated a significant increase in organic acids and a decrease in reducing sugars in the grape clusters treated with salicylic acid. The highest amount of tartaric acid was found in the treatment with 2 mM salicylic acid, with an average of 0.66, while the control treatment had the lowest amount of tartaric acid, with an average of 0.52. This suggests that the use of salicylic acid led to a reduction in transpiration and consumption of organic acids. In terms of reducing sugars, the highest and lowest amounts were observed in the control treatment (14%/74) and the treatment with 2 mM salicylic acid (13%/60), respectively. Increasing the concentration of salicylic acid up to 2 mM resulted in the enhancement of anthocyanins and phenolic compounds contents, but higher concentrations (more than 2 mM) reduced the amounts of these compounds in treated fruits.

 Pre-harvest use of salicylic acid could have a positive effect on the improvement of qualitative and quantitative characteristics of grape cv. Shahroodi. However, further comprehensive studies are needed to be conducted to recommend this compound to the growers of fruit trees.

Recently, the use bioregulators to ameliorate the effects of environmental stresses on agricultural products has been considered. This split plot experiment was conducted as a randomized complete block design to investigate the moderating effect of some bioregulators on vegetative, biochemical and yield characteristics of greenhouse tomatoes under drought stress in the research greenhouse of University of Hormozgan. Experimental factors were three drought stress levels as the main factor, were include full irrigation as control, moderate and severe drought stress, respectively, irrigation of plants based on providing 100, 75 and 50% readily available water, and foliar application of 0.5 g per plant of biological compounds (the first time one day before applying drought stress and the second time before flowering begins) as a sub-factor including control (without the use of compounds), proline, chitosan and N-Succinyl and N, O dicarboxymethylate chitosan (NSC and NOC, respectively). Application of bioregulators at each water stress level increased the of proline content and catalase and peroxidase enzymes activity in comparison with the control, which in most cases the highest increase in enzyme activity related to NSC. Chitosan derivatives, on the other hand, were able to reduce the amount of malondialdehyde (MDA) and hydrogen peroxide in tomato leaves. Among the biological compounds, NSC and chitosan had the greatest improving effect on the fruit yield via increasing the number and diameter of fruit. So that foliar application with NSC increased fruit yield in control, moderate and severe water stress by 5.33, 17.91 and 33.24%, respectively. Therefore, according to these results, under deficit irrigation conditions, chitosan and its derivatives can reduce the effects of drought stress on tomatoes more efficiently than proline.

Climate changes and agricultural practices such as excessive use of chemical fertilizers and pesticides have intensified the effect of abiotic pressures on crop productivity and have destroyed the ecosystem. One of the strategies to moderate these pressures is the use of organic fertilizers, mycorrhizal symbiosis and microbial inoculation. In order to investigate the effect of organic fertilizer, mycorrhizal fungi and Bacillus on the growth characteristics of bell pepper, an experiment was carried out as split plots on a randomized complete block design with the main factor of organic fertilizer at two levels (with and without organic fertilizer) and the secondary factor of biofertilizer treatments at four levels [arbuscular mycorrhizal (Rhizophagus irregularis + Funeliformis mosseae), Bacillus (B. subtilis + B. amyloliquefaciens)., mycorrhizal + bacteria mixture and control without inoculation] in three replications. Soil biological properties, nutrients uptake and growth characteristics and yield of the fruit were investigated after harvest. The results showed that the organic fertilizer and mycorrhizal fungi application increased the shoot dry weight (10.3% and 17.4%, respectively) and fruit yield (11.5% and 19.9%, respectively) compared to the control. The highest microbial population (1.1 × 107 CFU g-1) and R/S ratio (110.0) were obtained in the organic fertilizer application treatment with mycorrhizal inoculation. Mycorrhizal symbiosis with organic fertilizer application improved the uptake of nitrogen (20.6%), phosphorus (46.8%), iron (35.6%) and zinc (57.2%) compared to the control, and potassium uptake was improved by Bacillus treatment as compared to the control, it increased by 22.3%. In general, the combination of organic fertilizer and mycorrhizal fungi seems to be suitable for greenhouse bell pepper cultivation.

In order to study the effect of different chemical and organic fertilizers on the morphological characteristics of physalis an experiment as split plot based on randomized compelet blok design was done in the greenhouse. The main plot includes organic fertilizer at four levels (control, farmyard manure, vermicompost and the combination of farmyard manure and vermicompost) and sub plot included different chemical fertilizers at six levels (control, NPK chemical fertilizer, potash chelate 28%, iron nano chelate 15%, superahyomic and biomass biofertilizer). The results showed that in the culture medium of farmyard manure + vermicompost and with the application of nano-biological biofertilizer, the highest fruit yield per plant (2.29 kg/plant), vitamin C (8.53 mg/g fresh weight), phenol (39.90 mg GA/DW) and total flavonoids (6.89 mg QA/DW), antioxidant properties and soluble solids (16.5 Brix) are obtained in the fruit. The highest and lowest concentrations of nitrogen, phosphorus and potassium of shoots were observed in the treatment of vermicompost + farmyard manure, respectively, along with nano-fertilizer, biofertilizer and control treatments. Considering the favorable effect of vermicompost in the culture medium and biological fertilizers in comparison with the control treatment and chemical fertilizer treatment, it can be considered in the cultivation and feeding programs of physalis in addition to maintaining and improving traits related to growth and yield a healthy product can be offered without chemical fertilizer residues.

This study was conducted to investigate the effects of nitrogen, iron and zinc on the fruit quantity and quality of the 6-years-old sweet lime trees budded on Mexican lime rootstock in the research orchard of Jahrom Islamic Azad University. For this purpose, nitrogen, zinc and iron elements (from sources urea, iron sulfate and zinc sulfate, respectively) were foliar sprayed at concentrations of 0, 3 and 5 g L-1, alone and in combination, before flower induction, in October 2017. The experimental design was factorial based on the randomized complete block design with 27 treatments and three replicates and one sweet lime tree per each replicate performed at two separate locations in the orchard named groups A and B (each group included 81 trees). Based on the results, different amounts of nitrogen, iron and zinc, individually and in combination, had significant effects on all quantitative and qualitative traits of sweet lime fruit atP≤0.05. The effect of location was significant only on the total acids, vitamin C and fruit juice percentage. The highest average fruit weight (228 g) and yield of a single tree (313 kg) was obtained from the combined application of N, Fe and Zn elements at the highest concentration (5 g L-1). The highest TSS and total acid (10.62% and 0.208 mg L-1, respectively) were observed by application of 5 g L-1 Fe without N and Zn, in addition the greatest vitamin C was recorded by application of combined treatment of 3 gL-1 N and Fe and 5 gL-1 Zn with 56.93 mg/100 ml fruit juice.

In order to study the application of zeolite on quantitative and qualitative characteristics of carela medicinal plant under deficit irrigation, a factorial experiment was conducted in a completely randomized design with three replications in a greenhouse at the Agricultural Institute, University of Zabol during 2018. Experimental factors included deficit irrigation in three levels, (90, 70 and 50 % F.C.), and four levels of zeolite (0, 20, 30 and 40 g/kg of soil). The results showed that application of zeolite increased fresh and dry fruit weight, fruit diameter and fruits number per plant and deficit irrigation had a decreasing effect on the mentioned traits. Application of zeolite at all levels of deficit irrigation increased plant length, fruit length, fruit yield, chlorophyll a, b and carotenoid, vitamin C and alkaloids, so that the highest amount of these traits was obtained from 40 g/kg zeolite. In general, application of zeolite was helpful in reducing the adverse effects of deficit irrigation on carela's quantitative and qualitative traits.

Peach (Prunus persica L.) is one of the most essential fruit in Iran and the world. This fruit is suitable for both fresh markets and industrial producer and it is quite favorable by consumers. The efficiency of production is strongly influenced by the chosen peach cultivars. New cultivars are constantly in development by breeders. However, all characteristics are required to be examined include their ecological adaptation ability, productivity, fruit quality, and market value before orchard establishment. Studying the new cultivars is practically essential for exact determination of morphological and phenological features of genotype which is important. However, there is limited information on the global evaluation of fruit quality in breeding progenies and their relationships with pomological traits. Furthermore, the cultivated peach area under Khorasan Razavi province is 1850 ha and the production of fruit is 11283 tons. Therefore, the selection of suitable cultivars for cultivation in the region is very important due to the high economic lifespan of peaches (20-30 years), which in some commercial orchards this period is reduced to 12-15 years. Therefore, this study aims to evaluate the pomological and morphological traits of 14 peach genotypes and cultivars in Khorasan Razavi province climatic conditions to select cultivars or genotypes compatible with high quantitative and qualitative performance. This study was performed in two-years (2016-17 and 2017-18) experiments based on a complete randomized block design with three replications on 14 peach cultivars and genotypes in Golmakan Agricultural and Natural Resources Research Station on 4-years-old trees with density planting system at a spacing of 4 ×5 m. The type of applied irrigation was drip irrigation, with common fertilizer. Trees were trained to an open center system. The vegetative (tree height, trunk cross-section, the crown of the tree), phenological (first bloom, full bloom, end of flowering, flowering period, and harvest time) and reproductive (fruit weight, stone weight, fruit length, fruit width, fruit yield, total soluble solids, titratable acidity, flavor index, and pH) traits were evaluated. It is necessary to explain the soluble solids content by Refractometer (Model 7887, Osk Japan) in terms of percentage and acidity by titration with NaOH (0.1 N) based on predominant peach acid, malic acid. The ratio of soluble solids to acidity was obtained by dividing soluble solids by acidity. The pH of the fruit juice was measured with a portable pH meter at room temperature (23–18 °C). Data analysis was performed using SAS software (version 9.2) and means were compared using Duncan's multiple range test. Stepwise regression and cluster analysis (Ward method) was conducted by Minitab software (version 19). Simple correlation (Pearson) between traits from the mean of two-year data was performed using SAS statistical software (version 9.2), in which positive correlation with blue color and negative correlation with red color was determined, which increased the color intensity indicates an increase in the correlation coefficient. The results showed that year and genotype had significantly different effects on all studied traits. ‘Anjiri Maliki’ and ‘Shindabad Hastejoda’ were the earliest and the most late-flowering genotypes, respectively. Among the studied genotypes, ‘Shindabad-5’ and ‘Spring Time’ were the earliest fruiting genotypes, and ‘Meshkinshahr Paeeze’, ‘Kajil’, and ‘Anjiri Zafarani’ were the most late-fruiting genotypes. ‘Haj Kazem’ genotype had the highest tree height (236.18 cm), trunk cross-section (181.83 cm2), and tree crown volume (73.34 cm3), which compared to the control genotype (‘G.H. Hill’) showed  38.62%, 79.9%, and 55.7% increases, respectively. In the second year of the experiment, the characteristics of fruit weight, stone weight, fruit length, fruit width, and fruit yield increased by 41.72%, 43.45%, 16.61%, 16.40% and 81.99%, respectively, compared to the first year. The highest amount of single fruit weight (165.28 g) in ‘Fayette’ genotype, stone weight (7.04 g) and fruit length (65.05 mm) in ‘Shinabad Hastejoda’ genotype, fruit width (66.04 mm) in ‘Shandabad-5’, and fruit yield in ‘Fayette’ and ‘Paeeze Meshkinshahr’ genotypes (with an average of 21.78 and 21.33 kg, respectively) were obtained. ‘Anjiri Zafarani’ genotype had the highest content of soluble solids (16.95%), flavor index (48.38), and acidity (4.65), which compared to control genotype were increased 0.1%, 69.38% and 25.8%, respectively. Fruit yield had a positive and significant correlation with trunk cross-sectional traits, tree crown volume, fruit weight, stone weight, and fruit width. According to this study, the tree height, trunk cross-section, and fruit weight traits were entered into the regression model, respectively, and finally, the traits entered in the model justified 53.23% of the fruit yield changes. Generally, ‘Fayette’ and ‘Shindabad Hastejoda’ genotypes can be recommended as the best genotype for cultivation in the Khorasan Razavi region due to their high quantitative and qualitative yield.

Nowadays, spraying and foliar feeding represent one of the most effective techniques of applying essential nutrient elements to crops and to optimize the application of fertilizers in agriculture. In this research, effect of foliar application of different concentrations of ammonium sulfate on quantity and quality traits of cucumber under greenhouse conditions was investigated. The research was performed under completely randomized design with 6 treatments of foliar application of ammonium sulfate (0, 25, 50, 75, 100 and 150 mM) with 4 replications. Results of this research showed that plants in 25 mM ammonium sulfate and control treatments had the highest chlorophyll content, number of lateral shoots, number of fruits, and fruit yield. Vegetative traits such as chlorophyll index, number of lateral shoots, number of fruits, and fruit yield were reduced significantly under 100 and 150 mM foliar application of ammonium sulfate. The lowest number of fruits and yield were obtained in 150 mM treatment. Plants in 100 mM treatment had the highest percent of leaf dry weight. Foliar application of ammonium sulfate, except 25 mM, resulted in fruit firmness reduction as compared to control plants. On the other hand, foliar application of ammonium sulfate, regardless of concentration, resulted in higher fruit weight loss compared to fruits from control plants under normal room temperature. Therefore, for optimum growth and production of cucumber under greenhouse conditions, foliar application of 25 mM ammonium sulfate (low concentration) is recommended.

In order to investigate the effect of nitrogen and plant spacing on phenological characteristics, morphology, and fruit yield in pumpkin (Cucurbita pepo L.), an experiment was conducted at the farm of Agriculture Faculty, Azarbaijan Shahid Madani University, during 2013. The study was performed as factorial in a complete randomized block design with three replications. The treatments consisted of nitrogen at five levels (0, 50, 100 and 200 Kg ha-1) and plant spacing with a square array at three levels (30, 60 and 90 cm). According to the results, the planting time until flowering and fruiting was longer in the treatment of 200 kg N. The number of nodes, sub-branches, and leaves per plant was higher in the planting space of 90 cm along with 200 Kg ha-1 nitrogen. The higher plant length and fruit yield were recorded for the planting space of 60 cm along with 150 Kg ha-1 nitrogen. The highest leaf dry weight was related to the 200 Kg ha-1 nitrogen. The use of 150 Kg ha-1 nitrogen caused to the highest number of male and female flowers, fruit fresh weight, number of seeds per fruit. The higher leaf dry weight, male and female flowers, and fruits per plant were obtained in the planting space of 90 cm. Finally, the application of 150 Kg ha-1 nitrogen and planting space of 60 cm led to the highest number of fruits and fruit yield in unit area.

Calcareous soils with high pH in Jiroft region have caused difficulties in uptake of micronutrients, particularly iron (Fe), by strawberry plant. In the present greenhouse research, treatments consist of combination of different sources, application method and amount of iron application. Results showed that soil application of 10.5 kg/ha chelated iron (Fe-EDDHA) had the highest fruit yield, average fruit weight and vitamin C content. Based on the orthogonal comparison, in general, applying iron with any method of application and combination significantly affected most of the measured plant traits (with the exception of fruit acidity and vitamin C content). Therefore, regardless of the type and method of iron application, its application is necessary to increase yield and other quality parameters of the strawberry under greenhouses conditions in Jiroft region. Economic evaluation of the treatments showed that spraying iron sulfate and Fe-HEEDTA is not economically justified due to the costs imposed on greenhouse owner. Generally, soil application of Sequestrene-138-Fe is economically valuable, compared with spraying of iron sulfate and Fe-HEEDTA. Using 4.5 kg/ha Sequestrene-138-Fe has higher economic justification and higher profitability rate (1979.95% in comparison with 1345 and 1176.89%, respectively) compared to 7.5 and 10.5 kg/ha. Thus, soil application of 4.5 kg/ha Sequestrene-138-Fe (Fe-EDDHA) for greenhouse production of strawberry in Jiroft region, which have similar conditions to the present experiment, is recommended.

In order to study the effect of different amounts of nitrogen fertilizer and foliar application of boron on some physiological traits in karela plants (Momordica charantia L.), a factorial experiment in a randomized complete block design with three replications was conducted at the Sharood University of Technology in 2013. The treatments consisted of three levels of nitrogen fertilizer: 75, 150 and 225 kg N.ha-1 (urea source) as the first factor and four foliar applications of boron including: 0, 1, 2 and 3 g per liter of boric acid as the second factor. The traits measured in this study included the length and diameter of fruit, fruit yield, chlorophyll "a","b", and carotenoids, the conent of sugar nitrate and nitrate reductase enzyme activity. The results showed that, nitrogen fertilizer except diameter of fruit had significant on all of attribute traits. Foliar application of boron in this study had significant effect on fruit yield, the content of chlorophyll "b" (P

In order to investigate drought stress tolerance and adaptation in 15 Iranian endemic coriander (Coriandrum sativum L.), three experiments were conducted separately through randomized complete block design whit three replications in field conditions. In experiments, the coriander populations were well watered, stressed at one step and stressed gradually, respectively. In this research, 17 phonological, morphological and physiological traits were measured. Results of univariate and multivariate combined analysis of variance showed the difference among experiments and coriander populations for drought tolerance. Means comparison through LSD test showed significant difference among experiments for the most of traits. The highest effect of drought stress was on the fruit yield. Three dimensional diagrams based on geometric mean productivity for fruit yield and fruit essential oil content revealed that P10 can be introduced for fruit and essential oil production in regions that have drought stress problem at the end of growth season. The highest broad sense heritability was observed for fruit number per plant in the first experiment and harvest index in both drought stressed experiments. By considering heritability and genetic gain of fruit number and fruit yield traits, production of hybrid variety can be suggested for improving these traits.

Iran is one of the main producers of peach fruit, therefore increasing fruit quality and quantity is important. It has been reported that brassinosteroids are able to improve yield and quality of fruits. In present research, the impact of foliar spray of peach plants cv. ‘Alberta’ with 24- epibrassinolide (0, 0.1, 0.5, 1 μM EBL) at two stages namely; before flower opening, after fruit set and the combination of two stages was studied on fruit number, diameter and weight, stone length, diameter, weight and the ratio of fruit weight to stone weight, leaf chlorophylls, ion leakage and fruit yield. Compared with control, 1 μM EBL applied before flower opening increased leaf chlorophyll, fruit number, length, diameter and also stone length, diameter and weight and fruit yield. All treatments applied reduced leaf ion leakage. However, it is concluded that EBL applied before flowering is able to reduce flower and fruit abscission whenever needed.

Plastic mulches have been used in vegetable production in the most parts of the world. In order to evaluate the performance of the colored plastic mulch and different plant density on Cucurbita pepo var. Rada, an experiment was conducted in Agriculture Faculty of Ferdowsi University of Mashhad during the cultural seasons at 2010. The experiment was arranged in factorial experiment based on randomized complete design with four replications. Treatments were mulch at three levels (blue, red and without mulch) and plant spacing at two levels (120 × 30 and 120 × 40 cm). The results indicated that reducing the planting distance (120 × 30 cm) significantly increased the fruit weight and yield. The highest numbers of harvest and fruit yield were found in the red mulch treatment. The fruit yield per plant was 5/36, 3/57 and 2/69 kg in the red, blue mulch and control, respectively.

In order to study the effect of planting date and planting pattern on Chararjo melon (Cucumis melo var inodorus) fruit yield and yield components, an experiment was carried out in an RCBD arranged in a splitfactorial design with four replications. The study was conducted at the Agriculture Research Station of Gonbad for two years (2006-2007). Main plots consisted of four planting dates (April 9, April 21, May 5 and May 22). Sub-plots were combination of row spaces (180, 230 and 280 cm) and within row distances (50 and 70 cm). Plots were furrow irrigated. To obtain fruit yield, fruit weight, fruit number per plant and per hectare, fruits of two middle rows were hand-picked. Analysis of variance was performed each year and means were compared using F protected LSD. To analyze the data, S.A.S. was used. The results showed that with a delay in planting, fruit yield decreased. The fruit yield decease with a delay in planting might be attributed to acceleration of growth stages and shortened period of assimilate accumulation and lesser vegetative growth caused by higher temperatures. Row space 180 cm had the highest fruit yield. There was not any significant difference for fruit yield between two in- row distances, i.e. 50 and 70 cm. Based on two year results, and considering fruit yield and fruit weight, the suitable planting date for Charjo melon in the region might be early April. The appropriate planting pattern might be 180 cm by 70 cm.