فهرست مطالب طاهره ‍‍‍پروانه

In order to study three vegetative rootstocks M9, M7 and MM106 on some growth and biochemical Characteristics of Apple cvs. "Golden delicious" and "Red Delicious", an experiment in factorial design based on randomized complete blocks with four replications in orchard of Mashhad agricultural research center was performed in 2021. Some characteristics: including trunk diameter, current shoot growth, leaf area, chlorophyll, phenol content, anthocyanin and antioxidant properties in leaf sample were measured. Results showed that in the interaction of rootstock and scion had a significant effect on the trunk diameter, leaf area and anthocyanin. The highest amount of anthocyanin (0.466 mg.g-1FW) at "Golden delicious" on M9 rootstock was measured. Also, "Red Delicious" on MM106 rootstock had the largest trunk diameter (47.81 cm2) and "Golden delicious" on MM106 rootstock showed the highest leaf area (31.45 cm2). The results of this study showed that MM106 rootstock by showing high levels of growth Characteristics compared to the M9 and M7 was placed in a better position. And M9 rootstock by having biochemical Characteristics was better than two other rootstocks. Cultivars on M9 rootstock with highest amount of anthocyanin was suggested as a valuable grafting compounds in terms of health benefits under Mashhad Climatic Conditions.

This study was conducted to investigate the effect of vegetative rootstocks and nutrient content on some of the most important flavonoid compounds in leaf samples of Bastam genotype (BA) and Bekran (BE) cultivar and compare them with the Red Delicious cultivar flavonoids. The experiment was conducted in a factorial way of randomized complete blocks over two years. Sampling of three-year-old trees grafted on M9 and B9 rootstocks and Bekran genotype colony rootstock was done and then the amounts of nutrients including nitrogen, phosphorus, potassium and calcium and some of the most important flavonoids including Quercetin, Kaempferol, Rutin and Luteolin in Leaf samples were measured using high performance liquid chromatography (HPLC). The results of this study showed that during two consecutive years, the amount of flavonoid compounds Quercetin, Quercetin 3-ramenoside, Luteolin, and Kaemferol were affected by rootstock and scion and their interaction. Step-by-step regression analysis showed that the amount of each element had a significant specific effect on the biosynthesis of flavonoid compounds. The total amount of flavonoid compounds in leaf samples of cultivars and genotypes grafted on M9 and Bekran colonies rootstocks increased in the second year. Also, with increasing plant age and root development, increased. The total amount of flavonoid compounds in leaf samples of cultivars and genotypes. The results of this research showed that the inherent differences between cultivars determine the amount of synthesis of secondary metabolites, but the amount of these compounds can be increased by using rootstocks that have obvious differences in vigor or are more efficient in absorbing and transporting nutrients.

Numerous studies have been performed on the effect of rootstock and cultivar on physicochemical traits of apple fruit with their results showing different effects of these two factors. In order to study three vegetative rootstocks on some quantitative and qualitative characteristics of apple cultivars "Golden Delicious" and "Red Delicious", an experiment was carried out in factorial design based on randomized complete blocks with four replications in orchard of Mashhad Agricultural Research Center in 2021. Fruit quantitative and qualitative characteristics, including weight, volume, density, length, diameter, firmness, pH, total soluble solids, phenol content, antioxidant properties and anthocyanin have been measured. The highest amount of total phenol (652.9 μg.g-1FW) and anthocyanin (35.9 mg.g-1FW) has been measured in "Red delicious" on M9 rootstock. The results of this study show that "Red delicious" has had the highest amount of diameter (78/64 mm) and weight (166/9 g). The highest amount of fruit firmness has been observed in M9 rootstock (5/64 kgcm-3). In general, the results of this study indicate a different effect of rootstock and cultivar interaction on the studied characteristics. Depending on the purpose of gardener, different grafting compounds can be recommended "Red delicious" on M9 and MM106  rootstock with highest amount of total phenol and anthocyanin is suggested as a valuable grafting compounds in terms of health benefits under Mashhad Climatic Conditions.

Introduction :

Apple is one of the most important horticultural crops in Iran. The aim of this study was to investigate the effect of genotype on physical and chemical properties of fruit; to evaluate the amount of fruit secondary metabolites and correlation between them with the enzymatic browning in some Iranian apple cultivars. Recently red-fleshed apples have been attracted the attention of many researchers and fruit marketers because the flesh of those cultivars contains a high amount of red pigment anthocyanins, which show strong antioxidant activity. These cultivars have a better place in the market for the consumers because of the attractiveness, quality and high levels of anthocyanins and other phenolic compounds in fruits. Development of such new varieties with unique properties is important for improving the apple breeding and processing industry in the world. Phenolic compounds and flavonoids are products of the phenylpropanoid pathway. They are secondary metabolites and are responsible for different functions in the plant life cycle. Secondary metabolites play an important role in the quality of food (color, flavor, and odor). Also production of secondary metabolites may be a part of the plant defense system.

Materials and Methods:

 The fruits of ‘Morabaee-Mashhad’, ‘Top Red Delicious’, ‘Golab Kohanz’, ‘Winter Banana’, ‘Golab-e Kermanshah’, ‘Early Devan’ and ‘Pepin’ apple cultivars were harvested manually from trees at commercial maturity stage in Mashhad city, and ‘Red-flash’ apple cultivar was harvested in Shahrood city (Bekran Village), Iran. Fruits were transported to the laboratory soon after harvest. The measured chemical properties were consisted of total soluble solids (TSS), titrable acidity (TA), TSS: TA, total phenol content (TPC) and Antioxidant. Titratable acidity (TA) was determined by Korean models GMK855 and reported g 100 g-1 of malic acid. Total soluble solids (TSS) was determined at 20 ◦C with a refractometer and reported as ◦Brix. The pH value of fruit was measured with a pH meter at 20◦C. The pH differential method was used to determine the total anthocyanin content. The absorbance of the solution was measured at 510 nm. The total phenolic content was determined by a modified Folin-Ciocalteu reagent method. This experiment was conducted according to the completely randomized design; with thirty replicates. Data were analyzed statistically by SPSS statistical software and differences among means were determined for significance at p< 0.05 using Duncan’s multiple range test.

Results and Discussion:

 The highest and lowest of enzymatic browning was found in ‘Pepin’ and Red-flash apple cultivars, respectively. Red Delicious, Macintosh, and Liberty showed high levels of enzymatic browning. According to some researchers, there is a strong correlation between the amount of browning and total phenol content of apple varieties "Empire", "Rome", "Golden Delicious" and "Delicious"(oseteng and Lee 1987; Milani and Hamedi 2005).  San et al. (2002) revealed that there was a direct correlation between fruit phenolic content and antioxidant activity in 11 fruit species, indicating a significant contribution of phenolic compounds in the antioxidant activity of fruits. The results showed that the effect of cultivar on physic-chemical properties of fruit was significant at 5% probability level. The concentration of total soluble solids was significantly affected by cultivar, the highest concentration of total soluble solids was observed for Red-flesh apple cultivar while the lowest was recorded in Golab-e Kermanshah. Red-flesh and Golab-e Kermanshah cultivars had the highest and the lowest anthocyanin contents andthe highest and lowest of pH values were observed in Red-flesh and Golab Kohanz cultivars, respectively. The highest concentration of total phenolics was observed for Morabaee-Mashhad while the lowest was seen in Early Devan cultivars. The correlation between the enzymatic browning and antioxidant capacity of fruits was -0.507*.

Conclusions:

 The present research confirms that Red-flesh apple cultivar as a native fruit has been of interest to researchers and consumers because of its high amount of soluble solids, anthocyanins and flavonoids content, high level of antioxidant capacity and having a specific flavor and taste. Therefore, it can be a worthy cultivar for apple breeding programs and development in future.