Pomology
Masud Nazeri; Seyyed Jalal Tabatabaie; Yavar Sharafi
Abstract
Introduction
Water scarcity is one of the most important limiting factors threatening the production of horticultural crops. Approximately, 45% of the world's arable land is subject to permanent or intermittent water shortages, and approximately 50% of the world's annual yield is lost due to drought. ...
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Introduction
Water scarcity is one of the most important limiting factors threatening the production of horticultural crops. Approximately, 45% of the world's arable land is subject to permanent or intermittent water shortages, and approximately 50% of the world's annual yield is lost due to drought. Due to climate changes, especially the increase temperature and decrease rainfall in recent years in Iran, most of the gardens are facing limited water resources. In order to reduce water stress, increasing water use efficiency by naval technics seems to be crucial. Peach fruit growth mainly depends on adequate water supply. Therefore, water stress reduces the growth of the fleshy part and the quality of the peach fruits. Split root means placing a part of the root in different conditions compared to the remains of the root. Studies on split root culture were done in the laboratory for the first time. Increasing water holding capacity by split root system may improve soil- plant water availability. Furthermore, many studies indicated that Mycorrhiza and Trichoderma fungi improve the absorption of water and nutrients by plant. Increasing the absorption of water and nutrients leads to increasing growth and yield. The aim of this research was to improve the water efficiency and the use of low-yielding lands by placing a bag containing pumice and inoculating the roots with fungi.
Materials and Methods
This experiment was performed as a factorial experiment based on randomized complete blocks design with three replications for two years. Treatments included placing the bag close to the trunk of peach trees in three levels (without bag, one bag and two bags), different levels of irrigation (50, 75 and 100% of field capacity) and root inoculation treatments with mycorrhiza, Trichoderma fungi and control without fungus. Redtop peaches grafted on GF677 rootstock were planted in May 2018. The bags were placed at a depth of 60 cm and at a distance of 40 and 60 cm from the tree trunk. The bags size was 40 liters filled with pumice. At 20 cm from the top of the bag, three holes were made to remove excess water from that part and as a signal to cause the root to move towards the bag. For plants treated with mycorrhiza, 250 g of Mycorrhiza glomus was mixed and for plants treated with Trichoderma, 4.5 g of Trichoderma harizanium was mixed with pumice in the bag. In treatments with no bag placement, the plant roots were inoculated with fungi. Characteristics such as relative water content (RWC), yield, total soluble solids (TSS), titratable acidity (TA), TSS/TA, total phenol and fruit anthocyanin were measured at the end of growing season. Fruit skin color characteristics including L*, a*, b*, Chroma and Hue were measured with a colorimeter. Statistical analysis was performed by SAS software version 9.1. Mean data were compared using Duncan's multiple range test. drawing diagrams done by Excel software.
Results and Discussion
The results showed that bag placement increased RWC. The highest RWC of leaf was measured in the treatment of placing two bags, 75% irrigation and root inoculation with Trichoderma fungus. In the main effect of bag placement, irrigation levels and root inoculation, the highest RWC of leaf was observed in placing a bag, 100% irrigation and root inoculation with Trichoderma fungus, respectively. The treatment one bag, 100% irrigation and root inoculation with mycorrhiza improved vegetative growth and produced the largest trunk diameter. Yield in terms of fresh weight of fruit in two-bag placement, 100% irrigation and root inoculation with mycorrhiza was increased by 1.8 compared to the control. The highest TA was measured in the treatment of placing a bag, 50% irrigation and root inoculation with mycorrhizal fungus. Treatment without bag placement, 75% irrigation and without fungus inoculation had the highest total soluble solids and TSS/TA of fruit. The index ratio of TSS/TA is used to determine the taste of the fruit. The highest total phenol and anthocyanin of fruit was observed in treatments without bag under 50% irrigation levels. One bag placement, 75% irrigation without fungal inoculation treatment and no bag placement treatment, 50% irrigation, mycorrhiza inoculation caused the a* and L* of the fruit skin increased. The interaction effect of the three factors of bag placement, irrigation levels and root inoculation with fungus had no significant effect on Hue and b*.
Conclusion
The results of this experiment showed that water consumption can be reduced by placing a bag. The finding of the experiment led to the conclusion that a bag placement treatment, 75% irrigation and inoculation with mycorrhizal fungus improve fruit yield and quality of peach trees
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Abbas Joulani; Yavar Sharafi; Javad Sabbaghpour Heris
Abstract
Introduction: Sour cherry (Prunus cerasuc L.) is one of the most important stone fruit of Rosaceae family which have a high nutritional value. Based on FAO statistics, Iran was ranked the 3rd to 6th among the main sour cherry producer countries in the world. Most of the sour cherry cultivars are self-compatible, ...
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Introduction: Sour cherry (Prunus cerasuc L.) is one of the most important stone fruit of Rosaceae family which have a high nutritional value. Based on FAO statistics, Iran was ranked the 3rd to 6th among the main sour cherry producer countries in the world. Most of the sour cherry cultivars are self-compatible, but self-incompatible cultivars have been reported currently. Allotetraploidy of sour cherry complicates the self-incompatibility segregation in the progeny, so this studies have been less accomplished in Iran. The sour cherry is an allotetraploid species which possibly stand up as a result of usual hybridization between the dwarf cherry P. fruticosa and sweet cherry P. avium. Similar to other species of the Prunus, the phenomenon of gametophytic self-incompatibility (GSI) happens in sour cherry. It prevents self-fertilization and facilitate fertilization with pollen of other genotypes within same species. Self-incompatibility consists of arresting pollen-tube growth in the pistil if the pollen tube contains the same S-allele that is present in the pistil. The phenomenon of self-incompatibility in plants of Rosaceae family is controlled by two genes at the S-locus. The specificity of the pistil is encoded by a gene responsible for the synthesis of the ribonuclease protein (S-RNase), whereas the specificity of the pollen is controlled by the gene encoding an F-box protein (S-haplotype-specific F-box protein – SFB) 3a). The tightly linked genetic unit of the pistil S-allele (SRNase) and pollen S-allele is called S-haplotype. Materials and Methods: In the present study, pollen-pistil compatibility relationships among some sour cherry cultivars and selected genotypes were investigated by controlled pollination and pollen tube penetration by fluorescence microscopy. Cultivars were include ‘Meteor’, ‘Mont Morency’, ‘Majarestani’ and ‘Mahalli’ so, genotype1 were selected. After controlled pollination fruit setting was studied and the pollen tubes growth along the style was studied using fluorescent microscope. Crosses were selected based on synchronized flowering time among cultivars and genotypes and included ‘Mont Morency’ × ‘Meteor’, ‘Meteor’ × ‘Mahalli’, ‘Meteor’ × ‘Majarestani’, ‘Meteor’ × ‘Genotype 1’, ‘Mont Morency’ × ‘Mahalli’, ‘Mont Morency’ × ‘Majarestani’, ‘Mont Morency’ × ‘Genotype 1’, ‘Mahalli’ × ‘Majarestani’, ‘Mahalli’ × ‘Genotype 1’ and ‘Majarestani’ × ‘Genotype 1’, respectively. For each cross, 2 branches were randomly selected in female cultivars in winter. On each branch, including 30 floral buds at ‘balloon stage’ were tagged and bagged to prevent the entrance of any foreign pollen. On the day of anthesis, ready-to-dehisce anthers were collected from male cultivar, maintained on a moist filter paper in petri plates at 4 ºC in refrigerator till they dehisce. Pollens from these anthers were used as a source of male gametes later. Once stigma turned receptive, cross-pollination treatments were carried out in the field as designed scheme for 12 successive days. After every 24 hrs. up to 120 hrs. post-pollination, 12 pistils per treatment were fixed in FAA (formaldehyde/glacial acetic acid/70% alcohol in the ratio of 1:1:18) for 24 hrs. Followed by washings with water to remove traces of alcohol, if any, and cleared in 5% KOH at 60 ºC for fluorescence microscopy. Staining regime, as described in Sabbaghpour et al. (2020) the number of pollen tubes in the upper and mid-parts of the style and in the ovary was employed to enable visualization of the pollen germination on the stigma. Percentage of pollen germination was determined as the proportion of pollen grains that germinated on the stigma to the total number present on a scale of 100. Pollen tube number at three levels was calculated as an average of 5 (n=10). For an easy understanding of growth pattern of pollen tubes inside the style and ovary, the stylar portion, which measures 1.8 ± 0.07 cm on an average, was divided into two parts: the middle and the base. A single, longitudinal incision was then carefully given on one portion of the style using a fine needle and made wide open. Pollen tubes inside the style were critically observed under fluorescence microscope at 100x magnification. Number of them was carefully recorded and data generated for different experimental sets. Results and Discussion: Results showed that maximum pollen tube number penetrated to the ovary and final fruit set were observed in cross ‘Mahalli’בMajarestani’. Also, minimum pollen tube in the ovary and final fruit set were observed in ‘Meteor’בMahalli’ and ‘Meteor’בGenotype 1’ crosses. Conclusion: Based on the obtained results cross-incompatibility was not observed among the studied cultivars and genotypes. Therefore, they could be planted in the sour cherry breeding programs and orchards establishment based on their blooming time.
Sakineh Falah Moafi; Yavar Sharafi; Ayatollah Rezaei; Mohammad Hossein Fotokian
Abstract
Introduction: Favorable pollen transition on the stigma and pollen tube penetration is the most important for fruit setting in the apple. Boron is the main factor for pollen tube growth. A probable responsibility for boron in pollen tube growth may include vesicle making, transportation, fusion or the ...
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Introduction: Favorable pollen transition on the stigma and pollen tube penetration is the most important for fruit setting in the apple. Boron is the main factor for pollen tube growth. A probable responsibility for boron in pollen tube growth may include vesicle making, transportation, fusion or the successive formation of the pollen cell wall. Pollen tube cell walls are rich in polypeptides, glycoprotein, polysaccharides and arabino furanosyl which are known to form physically potent complexes with boron. Maximum cell boron content is located in the cell wall where it is associated with pectin compounds. However, under definite field conditions, foliar applications of boron have been resulted to raise fruit set by as much as 100% in many researches.
Materials and Methods: In this study effects of acid boric by 0 (as a control), 1000 and 2000 ppm concentrations was studied on the pollen tube penetration percentage to style and ovary in six crosses among four apple cultivars including "Fuji", "Gala", "Goldn delicious" and "Red delicious' by florescence microscopy method, 72 and 120 hours after pollination. All of the trees were 12 year old on EM126 rootstocks and foliar sprayed by H3BO3 as the boron source (0, 1000 and 2000 mg.L) in the October. Crosses among the cultivars were programmed as ♀Red delicious × Golden delicious ♂, ♂ ♀Gala× Fuji, ♀Red delicious × Fuji♂, ♀Red delicious × Gala ♂, ♂ ♀Golden delicious × Fuji and ♀Golden delicious × Gala ♂. For each cross four repeats in all direction of the tree were regarded and in each repeat at least two branches with 60 – 100 were labeled in winter. Selected female cultivar's flower buds at ‘D’ stage were bagged to prevent the entrance of foreign pollens on the closed pistils. Pollens collected from the male cultivar flower buds and maintained in freezer until using in the field pollination time. Pollen germination was tested in an in vitro medium before field application on the pistils. Selected female cultivar's flowers were pollinated with selected male parent pollen when the pistils were acceptable for pollens and repeated after 24 hours. Determination of pollen germination percentage and tube growth on the pistil and different parts of the styles was studied by the florescence microscopy method 72 and 120 hours after pollination healthy pistils were separated from the branches and fixed in FAA solution and prepared for fluorescence microscopy observation as indicated in Ortega and Dicenta (2006). In each pistil the number of germinated pollen grains on the stigma, the number of pollen tubes in the first, second and third section and so, in the ovary were determined by a fluorescent microscope. Because of the five partitions of the apple flower stigma and style; the mean of the five parts was evaluated for each of them. The experiment was carried out as a factorial based on completely randomized design with three factors including B in three levels (0, 1000 and 2000 mg.L), time (0, 72 and 120 hr after pollination) andsix crosses in five replications (at least 10 style per cross). Data was analyzed following SAS (26) software. Mean values were analyzed by Duncan’s multiple range test.
Results and Discussion: Results showed that all of the boron concentrations, time after pollination and crosses were significantly affected pollen germination percentage on the stigma and tube penetration to different parts of the style and ovary at P<.01 level. Maximum pollen germination percentage on the stigma (33%) was observed in ♀Goldn delicious × Gala ♂ cross which treated by 1000 ppm boron 120 hr after pollination. Also, maximum pollen tube penetration to ovary was observed in ♀Red delicious × Golden delicious ♂ cross (32.06%). However, best compatibility between them and boron effects on the pollen germination percentage and tube growth in the style. It was revealed that in all of the crosses pollen germination percentage and tube growth in the style was increased by boron treatments.
Conclusion; However, boron is one of the main growth elements by its role in the cytokinin biosynthesis which is the most important hormone affects pollen tube growth and penetration. In this research the foliar application of boron increased pollen germination and pollen tube growth in all of the studied four apple cultivars crosses. However, increasing the boron concentration led to increased pollen germination and pollen tube growth linearly.
