Extreme grazing, illegal logging, fire and irregular harvesting are factors of forest degradation and boundaries change particularly in the upper parts of Caspian forests. Planting of exotic species such as Larix with good adaptability in these areas due to cattle's avoidance of grazing and immunity due to psychical effects on forest residents for its unknown identity, can help considerably to reestablishment of forest cover in upland degraded areas. Since there isn't enough seed for seedling production in the country and its high prices of seeds and currency need for procurement from foreign countries using of techniques that reduce the time to obtain enough seeds in the country is necessary. Grafted trees in comparison to non-grafted trees produce seeds in shorter time. Therefore, obtaining success in grafting was due to two factors: grafting time and scion diameter. According to the obtained results grafting time and scion diameter in prob., level of 1% and interaction between two factors in prob., level of 5% were significant. Therefore, the best time for grafting according to vegetative activity of stock and scion was the time that stock buds started swelling and scion buds were dormant (March) and the best scion diameter was more than 2 mm.

This study was conducted to investigate the effects of cultivar, grafting method and epibrassinolide (EBr) and their interaction effects on grafting success rate and walnut scion growth. The experiment was carried out as factorial arrangements in randomized complete block design with five replications in agricultural and natural resources research and education center of Kerman province in 2023 and 2024. Experimental factors included: walnut cultivar at two levels, EBr at four levels and grafting method at two levels. The results showed that Cultivar × EBr interaction significantly affected graft success in 2023, and scion bud breaking time (SBBT), and shoot diameter in 2024. Cv. Fernor + 0.05 mM EBr or without EBr had highest grafting success rate (80-100%) in 2023. Cv. Fernor + whip budding + 0.05 mM EBr had the latest SBBT (July 7-11) in 2024. Cv. Fernor + whip budding had the greatest shoot length (35.53 cm) in 2023, and 85 cm in cv. Fernor + 0.15 mM EBr in 2024. Maximum shoot diameters (1.73 cm) were recorded in cv. Fernor + 0.05 mM EBr in 2023, and in cv. Fernor + patch budding + 0.05 mM EBr (2.5 cm) in 2024. Cv. Fernor + whip budding + 0.25 mM EBr had the highest leaf number (39 leaves) in 2024. Walnut cultivar had more pronounced effect on grafting success rate and was identified as the most important factor in walnut seedling growth compared to high concentration levels of EBr and grafting methods. Keywords: Walnut, scion, cv. Chandler, cv. Fernor, chip budding, patch budding, hormone. IntroductionCommercial walnut production using seedlings is inefficient due to genetic variability and poor nut quality (Hartman et al., 2011). Despite the ease and tradition of seedling propagation in Iran, it fails to meet growers’ economic expectations. Grafting is a practical and low-cost method for propagating late-blooming, high-yield walnut varieties. However, its success rate is limited. Studies have identified patch budding as the most practical and efficient grafting method with success rates up to 93.3% (Khajeali and Mohammadkhani, 2015).Factors such as grafting time, method, genotype, temperature, and humidity influence grafting success rate (Vahdati, 2003). Research has also highlighted the role of plant hormones especially brassinosteroids (BRs) in vascular tissue formation and graft union success (Engine and Gökbayrak, 2022). Although BRs have improved flower development in cv. Chandler (Engine and Gökbayrak, 2022), their effect on walnut grafting success rate remains unexplored. Therefore, development of commercial vegetative propagation protocols for producing superior walnut cultivars adapted to Kerman’s climatic and resources limited conditions is essential.This study aimed to identify the most effective combination of EBr concentration and grafting method to improve grafting success arte and scion growth of cv. Chandler and cv. Fernor walnut. Materials and MethodsThe experiment was conducted at the Rabor walnut research station (RWRS) situated at 2290 meter above the sea level, 57˚02′45″–57˚02′48″ E and 29˚16′31″–29˚16′44″ N. The annual rainfall and temperature of the experimental site were 210 mm, and 23 °C, respectively. Two walnut cultivars, Chandler and Fernor were selected due to their late leafing, high lateral bearing, and high‑quality of nuts which are popular among local walnut growers in Kerman province.The experiment was carried out as factorial arrangements in randomized complete block design with five replications in agricultural and natural resources research and education center in 2023 and 2024 Experimental factors included: grafting method (patch budding and whip grafting), cultivar (Chandler and Fernor), and EBr concentration (0, 0.05, 0.15, 0.25 mM), comprised in 16 treatments. In October 2021, 100 walnut fruits were sown in pots (35 × 10 cm), and after 21 months 80 seedlings were chosen. Scions of cv. Chandler and cv. Fernor were grafted on seedling rootstocks during June 15–17.Seedling growth traits were evaluated at the end of the growing season. Traits included graft success (qualitative evaluation in 2023), SBBT, shoot length, shoot diameter, and leaf number (measured in both 2023 and 2024). Data were analyzed based on factorial experiment in randomized complete block design using SAS 9.1. LSD test was used for mean comparisons, and graphs were depicted using Excel 2013 software. Results and DiscussionGrafting success rate in walnuts were significantly influenced by the cultivar × EBr concentration interaction. EBRs are plant hormones, but their specific role in graft success needs further investigation alongside other crucial factors like phenolic compounds, vigorous rootstocks, and optimal environmental conditions. In 2023, cv. Fernor + 0.05 mM EBr showed the highest grafting success rate, but as the EBr concentrations inceased the grafting success rate decreased.In 2023 and 2024, cultivar × EBr × grafting method interactions significantly affected SBBT. Cv. Fernor + low concentration or without EBr had the latest SBBT, but cv. Chandler + 0.25 mM EBr had the earliest. Chip budding advanced SBBT by 7–9 days compared to patch budding likely due to better tissue contact. Cv. Fernor + chip budding + 0.15 or 0.05 mM EBr had the longest shoots, whereas cv. Chandler + low EBr produced shorter shoots. Leaf number was consistent in 2023, but varied significantly in 2024 in cv. Fernor + chip budding + 0.05 mM EBr producing the highest leaf number (39 leaves). Cv. Chandler + chip budding + 0.25 mM EBr had lowest leaf number the fewest (9 leaves). Shoot diameter also varied in different treatments, and the thickest shoots was produced in cv. Fernor + patch budding + 0.05 mM EBr.In conclusion, walnut cultivar had more pronounced effect on grafting success rate, and was identified as the most important factor in walnut seedling growth compared to high concentration levels of EBr and grafting methods. References Engine, H. and Gökbayrak, Z. 2022. Effect of brassinosteroid applications on flower sex distribution of 'Chandler' walnut cultivar. Journal of Agricultural Sciences, 32(3), pp.548-554. DOI: 10.29133/yyutbd.1053275Hartmann, H.T., Kester, D.E., Davies, F.T. and Geneve, R.L. 2011. Plant propagation: principles and practices. Pearson Education publication.USA. 425 pp.Khajeali, M. and Mohammadkhani, A. 2015.  The Effects of timing and grafting methods on graft success and scion growth in walnut (Juglans regia L.). Journal of crop production and processing, 5(15), pp.47-55 (in Persian). DOI: 20.1001.1. 22518517. 13Vahdati, K. 2003. Nursery management and grafting of walnut. Khaniran Publications. Tehran, Iran. 128 pp. (in Persian).

Two experiments were conducted to find out the best grafting date and best bed system to induce enough callus in grafting union. Both experiments were run in the greenhouse of Department of Horticulture, Faculty of Agriculture, the University of Tehran during year 2001. Two methods of grafting i.e. side-grafting and saddle-grafting were applied in two separate experiments. In the first experiment, using side-grafting technique, one-year old Persian walnut seedlings with diameter of 2-4 cm were used. In the second experiment, using saddle-grafting technique, thin (1-2 cm.) one year old seedlings were used. In these experiments, effects of date of grafting (22nd December and 22nd January), and kind of callusing bed (hot bed and normal bed without heating system at the bottom) were studied as a factorial in completely randomized design with three replications of 20 plants/ plot. Results showed that in the first experiment, using side-grafting technique, date of grafting had highly significant effect on grafting success in a way that first date was much more successful than the second date. Kind of callusing bed had no significant effect. However, in this experiment, the best result was obtained by grafting at the first date and using hot bed. In the second experiment, using saddle-grafting technique, first date was more successful than the second date but the differences did not reach significant level. Kind of callusing bed had also no effect.

This study was conducted to evaluate the effects of scion properties (number of buds on scion, presence of terminal bud on scion, and scion diameter and length) on success of epicotyl grafting and early growth of grafted walnut ‘Chandler’ at the college of Aburaihan of University of Tehran, during 2013-14. Grafting success, survival of the grafted trees, callus quality, shoot length and leaf number per tree were measured 150 days after grafting. No significant differences were found between scions containing terminal bud or lateral buds. The highest callus quality, grafting success (83.4 percent) and survival rate (72.8 percent) were obtained by using double bud scions. Using scions with 3-6 mm diameter significantly increased grafting success (73.4 percent) and survival rate (61.1 percent) of the grafted trees. The highest survival rate (56.1 percent) was found in trees grafted with 7-12 cm scions. The highest leaf numbers were found in the trees grafted with double bud scions, and 7-12 cm scions (9.1 and 8.6 leaves, respectively). The longest shoots were observed in trees grafted with scions containing two bud, and 3-6 mm diameter and 7-12 cm length (9.1, 12.7 and 12.2 cm, respectively). In conclusion, using scions containing two buds, with 3-6 mm diameter and 7-12 cm length were suggested to improve success of epicotyl grafting and quality of the grafted walnut ‘Chandler’ trees.

The aim of this research was to investigate the effect of different grafting methods and grafting times on the grafting success rate of and two commercial walnut cultivars (scion) under greenhouse conditions. The experiment was carried out as factorial arrangements in completely randomized design with three replications under greenhouse conditions of West Azarbaijan agricultural and natural resouces research and eduction cenetre, Urmia, Iran, in 2015-2016. The experimental treatments included three levels of grafting methods,whip grafting, chip budding, and T-budding, two times of grafting,early spring and late spring, and two commercial walnut cultivars,Chandler and Franquette. The highest final grafting success rate (58. 33%) was related to whip grafting followed by T-budding (38. 33%) and chip budding (31. 66 %), resspectively. The highest grafting success rate was obtained with whip grafting (64. 45%) in early spring. Also, interaction effect of grafting method × grafting time × cultivar was significant on the final grafting success rate. The highest final grafting success rate (83. 33%) related to T-budding of cv. Chandler in late spring. Introduction An important step for development of walnut cultivars with high-yielding and desirable quality is propagation using grafting methods (Soleimani et al., 2009). Many researches in different walnut growing countries have studied the effect of different grafting methods and grafing time on the success and productivity of grafted walnut cultivars and orchards. The degree of grafting success rates in these studies is very variable and depends on various internal and external factors (Vahadati et al, 2009). In addition to low graft coverage, frost damage to walnut grafted seedlings is considered as the second problem for production of outdoor grafted seedling nurseries (Ebrahimi et al., 2007). Rezaee and Naghilou (2016) studied the effect of grafting method and grafting time of seedlings in the open-air environment with application of micronutrient elements on grafting success rate, and concluded that the lowest frost damage of the top branches was related to saddle and chisel grafting methods. Ebrahimi et al. )2007) evaluated three methods of grafting in walnut,patch grafting, chip budding and T-budding, under greenhouse conditions in Niriz, Fars province in Iran, and reported that all three grafting methods were more successful as compared with open air conditions. The purpose of present research was to investigate the effect of different grafting methods and grafting times on the grafting success rate of two commercial walnut cultivars (scion) on seedlings rootstock under greenhouse conditions. Material and Methods This research was conducted using completely randomized design with three replications in a plastic greenhouse in agricultural and natural resources research center of West Azarbaijan province, Urmia, Iran, in 2015-2016. In this research, three grafting methods,whip grafting, chip budding and T-budding, two commercial walnut cultivars (scion),Chandler and Franquette were used in the early spring (first half of April) and late spring (second half of June). Necessary husbundary practices for the nursery including,weeding, irrigation, and fertilizers application was accomplished until the end of the growing season. Since there were zero values in data, the data was subjected to square root transformation, and then analysis of variance was performed using SPSS software. Duncan's Multiple Range Test, at the 5% probability level, was employed for mean comparsion. Graphs were drawn using SPSS and Excel softwares. Results and Discussion The analysis of variance showed that the grafting method, grafting time and cultivar had significant (p ≤ 0. 01) effect on the early and final grafting success rate, and scion length and diameter growth. The highest final grafting success rate (58. 33%) was related to whip grafting followed by the T-budding (38. 33%) and chip budding (31. 66 %). The highest grafting success rate was obtained by using whip grafting (64. 45%) in early spring (first half of April). Interaction effect of grafting method × grafting time × cultivar (scion) on final grafting success rate was also significant (p ≤ 0. 01). The highest final grafting success rate (83. 33%) and growth vigor obtained by using T-budding of cv. Chandler in the late spring (second half of June). Also, the least final grafting success rate (0%) was related to the chip budding of both cultivar and whip grafting of cv. Franquete in late spring. The results obtained from this research are consistent with the results of Ebrahimi et al. (2007). Thes researchers experimented three grafting methods, whip grafting, chip budding, and T-budding under greenhouse conditions, and reported that the highest grafting success arte was related to patch grafting (91%), followed by T-budding (31%) and the lowest grafting success rate associated with chip budding (19%). Also, the findings of the present resreach are consistent with the results of Ozkan and Gumus (Ozkan and Gumus, 2001) in Turkey.

Introduction: There are a few studies that compare the outcomes between primary and revision tympanoplasties. The purpose of the present study was to compare the results of type I tympanoplasty (i. e., synonymous to myringoplasty) and revision myringoplasty based on the closure of tympanic membrane perforation and hearing improvement. Materials and Methods: This prospective single-blind study was carried out on a total of 240 patients with tympanic membrane perforation at a tertiary referral center. The subjects underwent primary or revision myringoplasty. Grafting success rate and hearing results were measured and the comparison between the primary and revision groups was drawn. Results: Grafting success rate was reported as 96. 6% (112 out of 116 cases) for myringoplasty, while in revision myringoplasty the success rate of 78. 2% (97 out of 124 patients) was achieved (P=0. 001). Speech reception threshold was 23. 1± 9. 2 dB and 24. 9± 13. 1 dB in the primary and revision groups, respectively (P>0. 05). However, the percentage of air-bone gap on audiometry≤ 20 dB were 83. 8% and 76% in the primary and revision groups, respectively (P=0. 26). Conclusion: The findings of the present study have shown that although grafting success was reported significantly better in myringoplasty (tympanoplasty type 1), compared to that in revision myringoplasty, it did not reveal any superiority over revision tympanoplasty regarding the hearing outcomes. No consensus was achieved due to a great number of controversies in the literature.

High rate of root pressure is one of the main reasons of walnut grafting failure at early spring. In this experiment the effects of factorial combination of three seedlings vigor and three methods of root pressure control was investigated on the sap flow rate (SFR), grafting success percentage (GSP) and scion growth, in a completely randomized design with three replications. The effect of seedling vigor on the SFR trends and its correlation with the environmental variables during a 4-week period was studied as a separate experiment. According to the results, the SFR was similar for all of three groups of seedlings at the first week but, the trend of SFR was significantly separated during later weeks of measurements, so that it was decreased significantly in the case of low vigorous seedlings as compared to the vigorous and medium-vigorous seedlings (P<0.01). Also the rate of sap flow showed a positive correlation (r=0.98) with the minimum temperature of a day before of its measurement. The relatively late decline of SFR in low vigor seedlings did not significantly affect the GSP, but in combination with the one week of grafting delay resulted to the non-significant increase in the GSP as compared to vigorous seedlings (P<0.01). In addition, covering graft union with moist sawdust as well as grafting delay for one week resulted to the highest GSP (80-90%) independently from the seedling vigor. The growth rate of scions 45 days after grafting was affected significantly by the seedlings vigor (P<0.05). Thus, by controlling the root pressure via delay in grafting time and covering graft union by moist sawdust or avoiding usage of very vigorous seedlings of forest walnut ecotypes in the nurseries, it could be possible to obtain about 90% of GSP as well as a relatively significant reduction of scion growth.

In a two-phase experiment during 2018 and 2021, we evaluated the propagation success of avocado against three types of grafting (cleft, veneer, and splice) and two budding techniques (T and patch) practiced in the 3rd week of February, April, June, August, October, and December, considering the atmosphere of the six seasons (spring, summer, rain, autumn, late autumn, and winter, respectively) in Bangladesh. Cleft grafting was suitable during spring, demonstrating statistical superiority by exhibiting earlier bud sprouting (25.58 days) and better sapling qualities (16.27 cm scion growth and 14.57 leaves sapling-1). It produced a maximum number of transplantable propagules after ten months of grafting compared to all other combinations. However, commercial multiplications could not be satisfied with only a 48.00% success rate at the best combination. A post-grafting etiolation was therefore applied to the spring season’s cleft grafts. Out of 72-hour, 120- hour, 168-hour, and 216-hour etiolation and control (non-etiolation), etiolation up to 120-hour significantly augmented the success rate compared to the control treatment. The 216-hour etiolation treatment failed to produce any successful grafts. The earliest bud sprouting (21.37 days) with maximum bud sprouts (86.00%), transplantable grafts (78.67%), and superior quality grafts was obtained from the 120- hour etiolation compared to the other treatments, while the control treatment produced only 49.33% transplantable grafts. Thus, the 120- hour etiolation made 59.46% more transplants than the non-etiolation treatment. T-budding in winter was the worst technique and time for avocado grafting. Veneer grafting and the autumn season were the second-best options. Therefore, post-grafting treatment appeared best for avocado vegetative propagation.

Walnut propagation by seed produced a large number of natural hybrids with varation characteristics and clonal propagation of this plant is difficult. Walnut grafting is affected by xylem exudation and phenolic compound and Structural hormones play an important role in graft success and Survival of grafting plants. In this study the effect of phenolic compounds and structural hormones on Persian Walnut (Juglans regia L.) grafting success were evaluated. Three grafting season (March, June and Agust ) and four Walnut cultivar (K-21, K-28, OR-37 and OR-39) were used. Two grafting methods (omega bench grafting and patch budding).Were tried in controlled and non-controlled condition on 1 and 2 year old walnut rootstock. The highest grafting success (71/1%) was obtained from Agust graft from patch budding and march grafting success was low. The realation between Juglon and Auxin level and callus formation and grafting success were discussed. consequeutly a negative relation between graft success ration and joglon content and positive relation between Auxin leval and graft success was found. In adition effects of structural hormones were biologically tested with Coleoptile development, and a positive relation was found between the graft success ration and coleptile development.