جستجوی مقالات مرتبط با کلیدواژه « کیفیت پس از برداشت » در نشریات گروه « باغبانی »

Table grapes (Vitis vinifera L.) is one of the most important fruits that is widely grown in the world and is the export fruit of many countries. Although edible grapes are classified as non-climacteric fruits, they are very prone to spoilage due to their softening, weight loss, and decay caused by fungi, as a result which consequently leads to low storability. Different strategies have been postulated to maintain firmness and control decay of table grapes during storage and improve functional properties of fruit such as pre and postharvest chitosan coatin, and exogenous abscisic acid application. Table grapes have a short shelf life due to the thin pericarp and fleshy texture of the fruit. Polyamines (PAs) application also showed a significant role in extending the storage periods of several fruit species with maintenance of fruit quality. Postharvest treatments are not necessarily the best way of maintaining fruit quality during postharvest period. Such treatments are expensive, increase the risk of fruit damage through extra handling and also encourage grower to pay less attention to on-tree quality. Pre-harvest application considered as a good alternative to cope with mentioned problem. To the best of our knowledge, there is not any report in literature about the role of pre-harvest application of Pas and post-harvest table grape in Aloe vera gel (AVG) as a possible role in reducing mechanical damage of berries which leads to lower decays. Besides these, damage caused by human handling starts at harvest operation, which still occurs by hand for most fruits.

This study was done on 12-year-old mature grape varieties of ‘Yaghouti’ in two independent experiments in the scaffolding garden of Abestan region of Khorramabad city and laboratory post harvesting of horticultural sciences department of Lorestan University in 2019. Therefore, this study investigated the effect of foliar application before harvesting of putrescine (PUT) in three different concentrations (0, 2.0 and 3.0 mM) and immersion post-harvest fruit in AVG (25.0 and 33.0%) on grape fruit quality and shelf life of table grape (Vitis vinifera cv. ‘Yaghouti’) in five times (0, 9, 18, 27 and 36 day) during storage at 4° C.  The study was based on a factorial experiment with two pre-harvest spraying factors with PUT and post-harvest immersion in aloe vera gel (AVG) with three replications. The parameters of soluble solids (TSS), titratable acids (TA), ascorbic acid, total anthocyanin content (TCA), total phenol content (TPC), fruit firmness, shelf life of table grape (per day) were measured.

Fruits treated with both PUT concentrations showed greater firmness, vitamin C, total anthocyanin and phenol content, TSS, and during storage retained their shelf life longer than the control. At all five measurements, the highest levels of phenol and total anthocyanin content and firmness were related to the treatment of PUT 2.0 mM with coating of 25% and 33% AVG and the lowest was related to control. Also, pre-harvest use of PUT significantly prevented the softening of the fruit during storage and kept the firmness fruit.  Softening contributes to quality loss in reducing the shelf life, but PAs treatment resulted in maintenance of flesh firmness during cold storage. Therefore, Put- and Spd-treated grape have higher firmness at harvest leading to much lower mechanical injury during harvest and handling process and providing better transportability. The purple skin color of table grape was related to the presence of anthocyanin compounds, from which the anthocyanin malvidin-3-glucoside has been found as major component. Although, total anthocyanins were reduced in control and treated fruits during cold storage, but pre-harvest foliar spraying of Put delayed total anthocyanins concentration after 36 days of storage and decreased the loss of these compounds at the end of experiment. PAs have been described as anti-senescence agents and a great number of researches have been focused on the role of exogenous PAs on fruit ripening. Also it has been reported that the ripening process and senescence of table grapes is correlated with the anthocyanin concentration and profile. However, the data on pre-harvest application of polyamine on different fruit species are scant. Khan et al., (2007) showed that pre storage application of Put would retard fruit softening in ‘Angelino’ plum during cold storage by suppressing ethylene biosynthesis. In mango, Malik and Singh (2005) reported that pre-harvest application of PAs improved fruit shelf life, increased ascorbic acid content and retarded fruit skin color changes compared to control

Pre-harvest foliar application of Put on grapevines maintained higher firmness at harvest and postharvest periods and also improved the fruit quality in terms of phenolics, ascorbic acid, anthocyanin and also controlling weight loss during cold storage. Overall, the results showed that pre-harvest use of 2.0 mM PUT and post-harvest immersion in 25.0% and 33.0% AVG improved the shelf life of the cultivar by 16 days compared to control.

This study was conducted to investigate the effects of combined treatment of sodium alginate and ascorbic acid on the shelf life of strawberry fruits stored at 4±1 ° C. The treatments included control (distilled water), ascorbic acid (1%) with sodium alginate (1, 2 and 3%) and storage period for 7 and 14 days with 4 replicates. During storage, brightness index, chroma index, firmness, total acidity, vitamin C, phenol content, antioxidant activity and anthocyanin content were decreased, but the application of coatings preserved these indices as alginate 2% + ascorbic acid 1% was more effective to preserve these traits during storage. During storage period, polyphenol oxidase enzyme activity (50%), weight loss (2.8%) and pH (33%) increased. While the application of sodium alginate+ ascorbic acid preserved the lower levels of pH and the activity of polyphenol oxidize enzyme, it also controlled weight loss for 14 days.

In this research, the effects of calcium ascorbate (CaA) on storage life of tomato cv. Rio Grande (harvested at color breaking stage) was investigated during 40 days of storage. This study was conducted as a factorial experiment in a completely randomized design with 3 levels of CaA (0, 0.25% and 0.5%) and 4 levels of storage periods. Fruits were dipped in CaA solutions and after drying in room temperature, were transferred to cold storage at 13±1°C. 10, 20, 30 and 40 days after storage, some qualitative parameters, color indices and activities of polygalacturonase and pectin methylesterase enzymes were measured. Results showed that calcium content of treated fruits with 0.25% and 0.5% of CaA were 20 and 23% higher than controls, respectively. The firmness of 0.5% CaA treated fruits had less reduction (13%) during storage in comparison with untreated fruits. L* and pectin methylesterase enzymes of treated fruits with both concentrations were 3% and 29% less than control fruits, respectively. CaA treatments had not significant effects on color indices (a*, b*, Chroma and Hue angel), pH, TA, TSS, vitamin C, carotenoids and polygalacturonase enzyme activity, but storage time affected all measured parameters except TA. Generally, results suggest that CaA have potential in maintaining firmness and quality of stored tomato by increasing calcium contents of fruits and decreasing activity of pectin methylesterase enzyme.

This study was arranged to evaluate the effects of perlite-cocofibre substrate inoculation as the most prevalent media in gerbera soilless cultivation with two important arbuscular mycorrhizal fungi (AMF: Glomus intradices and Glomus mossea) on morphological, physiological and quality attributes of gerbera cut flower. Results showed the positive symbiosis between AMF and gerbera ('Stanza'), and consequently significant effects on morphological parameters such as leaf and flower number per plant, plant dry weight and physiological and biochemical parameters including stomatal conductance, photosynthetic pigments, antioxidant enzymes activity, soluable sugar and proline content. Also, flower quality indices including flowering-stem height, flower diameter and flower vase life were significantly affected by symbiosis of AMF. Based on the comparison of the meanss, except proline content and soluble sugars, the effects of both AMF spicies were similar on the measured parameters. As compared to control plants (without inoculation), substrate inoculated with both Glomus mosseae and Glomus intradices showed 16.33% and 19.09% more flowers were harvested per plant (yield) and 4 days higher flower longevity, respectively. Based on the results, inoculation of growth media with AMF had positive symbiosis effects and consequently, led to remarkable increasing of growth, yield and quality. Aaccordingly, application of AMF in soilless culture and especially supplemental experiments to assess nutrient use efficiency to achieve balanced nutrient and optimum using of mineral fertilizers in soilless systems could be recommend.

This research was performed to evaluate the effects of foliar application of nano-silicon (NSi), as a quasi-essential element, on yield, flower quality, vase life and infestation percentage of gerbera by greenhouse whitefly. Treatments were preharvest foliar application of different levels of NSi (0, 50 and100 mg/L) on gerbera 'Stanza' in a soilless system (to eliminate the effects of soil's Si) as a completely randomized design with three replications. Based on the results, activity of antioxidant enzymes including catalase and peroxidase and also flower quality such as flower diameter, stem height and longevity were significantly affected by NSi. Accordingly, NSi at 100 mg/L concentration showed the highest effect, compared with control (without NSi). However, yield or number of harvested flowers per plant were not affected significantly by NSi treatments. Also, whitefly infestation of isolated pots under NSi treatments showed less contamination percentage to whitefly egg, nymph, pupa and adult by 89, 99, 98 and 96%, respectively, as compared to control. Based on the significant and positive effects of NSi on flower quality and also whitefly control, further experiments could be recommended for comparison of NSi with other Si sources and chemical pesticides, and possible replacement of chemical fertilizers with Si-based fertilizers, particularly under soilless conditions.

Fragrant tuberose is the most important scented cut flower of Iran, which rank 4th among other cut flowers, based on the cultivation area and production. Due to the scarcity of water resources, soil constraints, and the aim of comparison and possible substitution of soil cultivation with soilless cultivation of tuberose, a pot experiment was conducted as factorial, based on completely randomized design with four replications, on two cultivars of tuberose (‘Mahallati’ and ‘Dezfuli’), in two greenhouse production systems, with soil and soilless medium. Based on the ANOVA results, photosynthetic capacity [number of leaves and leaf area, stomatal conductance and photosynthetic pigments content (chlorophyll a, b and total)], flower-stem height, number of florets, diameter of florets, nutrients uptake and flower vase life were significantly (P≤0.01) affected by culture system. Soilless system increased the flower-stem height and vase life (as the main quality indices of cut flowers) by 50% and 35%, respectively, as compared with soil cultivation. In addition, peroxidase activity, calcium, and potassium uptake were significantly (P≤0.05) affected by cultivar. Analysis of variance indicated that interaction of cultivar and cultivation system had significant effects on calcium uptake and number of leaves per plant. According to the results, soilless culture improved photosynthetic capacity and mineral uptake and subsequently increased quality and vase life of cut tuberose. This culture system showed high ability and potential to replace soil cultivation of tuberose.

Alstroemeria flower is one of the most important cut flowers in the world. Some materials can increase longevity of cut flowers. The aim of this research was evaluating the effect of some chemical solutions on postharvest Alstroemeria (cv. Stratus) cut flowers. This experiment was conducted with two factors of sucrose at four concentrations، 0، 5، 10 and 15 g/l and salicylic acid (SA) at four concentrations، 0، 100، 200 and 400 mg/l with three replication and arranged in a completely randomized design. During experiment، longevity، chlorophyll content، solution uptake، relative water content (RWC)، electrolyte leakage (EL) and leaf yellowing were evaluated. Analysis of variance showed that different levels of sucrose had significant effect only on electrolyte leakage of petal and chlorophyll content. The salicylic acid effect was significant at the one percent level on all traits except for electrolyte leakage of petal. The interactions between sucrose and SA on all traits at the five percent level had a significant effect. The results showed that treatment of 15 g/l sucrose had the highest chlorophyll content and the lowest electrolyte leakage of petal. The highest longevity، relative water content of leaf and petal، chlorophyll، solution uptake and the lowest electrolyte leakage of leaf and leaf yellowing were obtained from treatment with 400 mg/l of salicylic acid. Treated with15 g/l sucrose plus 400 mg/l SA had highest longevity، solution uptake and the lowest electrolyte leakage of petal in compared to the control. Thus، using 400 mg/l SA to increase the longevity and quality of Alstroemeria (cv. Stratus) cut flowers is recommended.

Humic acid (HA) with pseudo-hormonal activity has an important effect on nutrients uptake، yield and quality of crop products. Therefore، this experiment was conducted in soilless condition to evaluate the best HA concentration (0، 250، 500، 750 and 1000 MG/l) of nutrition solution and its effects on morphological traits، nutrients uptake، and postharvest vase life of pot marigold. Based on the results، HA showed significant effects on physio-morphological traits of pot marigold. Accordingly، as compared with control plants، the leaf area and chlorophyll content (a، b and total) as plant photosynthetic capacity، flower number and total phenol concentration were significantly affected by HA application. Also، as compared with control plants (without HA application)، HA showed a significant effect on P and Ca uptake. Flower longevity، as an important postharvest quality index، was increased 20% higher than control plants، in 250 mg/L concentration of HA. The results of the current investigation revealed that application of HA with 250 and 500 mg/L concentrations in soilless culture of pot marigold ‘cv. Crysantha’ could be recommended.

Grape as a remarkably perishable fruit is susceptible to fungal infections especially fungus Botrytis cinerea, an agent of gray mold and berry dehydration. Limitations have recently been placed upon uses of synthetic chemical compounds as regards of control postharvest losses in grape and in other susceptible fruits. In the present study a Prospective safe non-chemical control method was evaluated. An aqueous solution of 0.3 ppm concentration of ozone was applied to grapes cv. "Fakhri" in a test of three treatment times (5, 10 and 15 min). Quality characteristics (decay, vitamin C. content, reducing sugars, maturity index, weight loss, berry abscission, dehydration, cracking of berry and sensory analyses were assessed. Results indicated that treated fruits with ozone had lower decay percentage, weight loss, berry dehydration, berry abscission, berry cracking, while benfiting from higher reducing sugars, maturity index and storage quality as compared with control. In total, ozone treatment caused lower decay incidence and longer storability of the fruit.