Involvement of 1-methylcyclopropene in ripening of harvested mei (Prunus mume) fruit

Summary

Harvested mei (Prunus mume) fruit were stored at 20°C after exposure to 500 nl l^–1 1-methylcyclopropene (1-MCP) for 8 h. Firmness, peel colour, chlorophyll content, chlorophyllase activity, soluble solids content (SSC), titratable acidity (TA), respiration and ethylene production, and cell wall hydrolysis enzyme activities were monitored to determine the efficacy of 1-MCP treatment in delaying mei fruit ripening compared to untreated control fruit. Results showed that control ‘daqinghe’ mei fruit displayed typical climacteric patterns of respiration and ethylene production. Peak CO₂ production and ethylene production were observed after 6 d. Fruit softening was accompanied by a progressive decrease in colour parameters expressed as hue angle (h°), chlorophyll content, SSC, TA and increases in chlorophyllase, pectin methylesterase (PME) and polygalacturonase (PG) activities. 1-MCP treatment prior to the climacteric increase significantly delayed the onset of the climacteric peaks of CO₂ and ethylene production. These delays were associated with reductions in fruit softening, consistent with delaying the activities of PME and PG. Fruit treated with 1-MCP exhibited less peel colour change from green-to-yellow because of their lower levels of chlorophyllase activity and less chlorophyll breakdown. Moreover, 1-MCP treatment also significantly retarded reductions in SSC and TA compared with control fruit. The shelf-life of mei fruit ripening was increased by 4 d following 1-MCP treatment. Thus, 1-MCP treatment can markedly extend the post-harvest life of ‘daqinghe’ mei fruit.     

1-甲基环丙烯对‘富有’甜柿采后主要生理指标及细胞超微结构的影响

 以完全甜柿‘富有’ (Diospyros kaki L.‘Fuyu’) 为试材, 研究了在室温(20 ±2) ℃贮藏条件下1 - 甲基环丙烯(1-MCP) 0.50 μL·L^-1处理对果实的影响。结果表明: 1-MCP处理可显著抑制其呼吸速率、乙烯释放速率和衰老软化进程; 12MCP处理通过抑制果实中LOX活性的升高和MDA含量的积累,一定程度上维持了果肉细胞器和膜系统的完整性, 延缓甜柿果实的软化衰老进程。     

Changes in Ripening Behaviors of 1-MCP-Treated ‘d’Anjou' Pears After Storage

Abstract

1-Methylcyclopropene (1-MCP), an ethylene action inhibitor, was applied to ‘d’Anjou' pears (Pyrus communis L.) at 20°C between 2 and 5 days after harvest. Scald of ‘d’Anjou' pears was completely controlled by 1-MCP at a concentration between 0.05 and 0.3 µl l1 after a prolonged cold storage plus 7 days of exposure to an environment with or without 500 µl l1 ethylene at a temperature of 20°C or 25°C. 1-MCP inhibited the biosyntheses of α-farnesene and its oxidative products (conjugated trienes) and thus controlled scald. However, fruit treated with the above concentrations of 1-MCP did not ripen normally in an environment with or without ethylene. Ethylene production and fruit softening of 1-MCP-treated ‘d’Anjou' pears were inhibited during 7 and 15 days at 20°C. ‘d’Anjou' fruit treated with 0.01 and 0.02 µl l¹ 1-MCP ripened normally on day 7 at 20°C after 3 months of cold storage at ? 1°C, and ripened fruit did not develop any incidence of scald. Untreated fruit developed substantial scald. After 4 months of storage or longer, both untreated fruit and fruit treated with 0.01 and 0.02 µl l 1 1-MCP developed an unacceptable incidence of scald upon ripening. Thus, use of other scald control methods may be necessary in addition to treatment with a low dosage of 1-MCP to insure both normal ripening and scald control for d'Anjou pear fruit from the Mid-Columbia district.     

1-MCP verlängert die Lagerfähigkeit und vermindert Schalenbräune bei der Apfelsorte ‘Berlepsch’

‘Berlepsch’ as an apple cultivar of large vitamin C contents in excess of 30?mg vitamin C/100?g FM looses marketing share due to its poor storage quality and sensitivity to superficial scald. The objective of the present work was to use 0, 500 or 1000?ppb of 1-MCP (Smartfresh^TM) for 24 hours at 2?°C to overcome these two cultivar-related shortcomings. Slightly overripe apples were stored at 2?°C, 95% relative humidity either in normal air (NA) or in controlled atmosphere (CA) under 2% CO₂ and 1.8% O₂. Each of these six treatments consisted of four replicates of ca. 20?kg apples each. Treatments with 1-MCP did not affect the fruit sugar content. While the storage conditions (NA or CA) did not affect initial fruit respiration, 1-MCP reduced final fruit respiration to ca. 60% and 1-MCP effects on respiration rates in shelf life were more pronounced than in storage. While 1-MCP reduced the initial ethylene formation from 70 to nearly 0?μl/kg/h, this effect was declined with prolonged storage. Similarly, the temperature driven increase in ethylene evolution during shelf life was not affected by 1-MCP treatments. MCP treated fruit lost less weight in storage and shelf life relative to untreated fruits. Doubling the 1-MCP concentration from 500?ppb to 1,000?ppb did not further reduce respiration, ethylene formation, loss of fresh mass or incidence of superficial scald. This corresponds to the dose of 1-MCP commonly used in fruit storage.     

Effects of controlled atmosphere,edible coating,and 1-methylcyclopropene on improving storage quality of ‘Bartlett’ pears after long-term storage

Recent trends towards greater fresh market use of ‘Bartlett’ pears has increased the need to extend its storage life to prolong the packing and marketing season in the United States Pacific Northwest region. Sixteen and 38%, respectively, of control fruit developed senescence disorders following 5 and 6 months of storage at ?1.1°C. Commercial standard controlled atmosphere (CA) conditions (O₂ at 1.5 kPa and CO₂ < 1 kPa) or edible coating (Semperfresh?, SF) prevent the appearance of senescence disorders for 5 months, but 9% and 16% of fruit, respectively, developed senescence disorders after 6 months. The combination of CA+SF completely inhibited senescence disorders for 6 months. Treatment with CA and SF, alone or in combination, maintained high-storage quality and developed ripening capacity with characteristic melting texture during storage. Senescence disorders were inhibited for 6 months by 0.3 µL l^?1 1-methylcyclopropene (1-MCP), alone or combination with CA or CA+SF. In part these pears developed ripening capacity after 6 months of storage. The combination of CA+SF+1-MCP maintained the highest storage quality with dark green colour and hard firmness, which might be associated and proportional with reductions in ethylene synthesis and respiration rate after long-term storage.     

Maintenance of fresh boysenberry fruit quality with UV-C light and heat treatments combined with low storage temperature

Summary

Mature boysenberries (Rubus hybrid) were harvested, heat-treated (45°C for 1 or 3 h or 47°C for 1 h) or exposed to UV-C light (2.3, 4.6 or 9.2 kJ m^–2), and stored at 20°C for 2 d. Fruit treated with 9.2 kJ m^–2 or 45°C for 1 h showed less damaged drupelets per fruit and/or remained firmer than untreated fruit after 2 d. Those treatments were selected for further analyses. In another experiment, boysenberries were either UV-C (9.2 kJ m^–2) or heat-treated (45°C for 1 h) and stored either at 20°C for 1 d or at 0°C for 4 d before transfer to 20°C for 1 d. Both UV-C and heat treatments reduced softening and/or fruit damage. Treated fruit had lower respiration rates and anthocyanin leakage than control fruit suggesting greater tissue integrity. Titratable acidity, pH, total sugar content and antioxidant activity in treated fruit showed fewer changes than in control fruit when stored at 20°C for 1 d. Results suggest that heat or UV-C treatment, alone or in combination with refrigerated storage, may be a useful non-chemical mean of maintaining boysenberry fruit quality and extending postharvest life.     

Effects of 1-methylcyclopropene (1-MCP) on ripening of apple fruit without cold storage

Summary

The objectives of this study were to determine the efficacy of 1-methylcyclopropene (1-MCP) treatment on ripening of ‘Tsugaru’ fruit at different stages of maturity (early, mid-, and late harvest) and the responses of the early- to late-maturing apple cultivars,‘Tsugaru’,‘Hongro’ and ‘Fuji’, respectively, during storage at ambient temperature (20º ± 2ºC). Fruit at different stages of ripening were treated with 0.5, 1.0, or 2.0 µl l^–1 1-MCP for different durations (e.g., 1.0 µl l^–1 1-MCP for 8 h, 16 h, or 24 h) or with various delays before treatment (e.g., 1.0 µl l^–1 1-MCP on the day of harvest, or 1 d, or 2 d later). Application of 1-MCP to unripe fruit inhibited ethylene production, lowered the rate of respiration and maintained titratable acidity (TA) more effectively than when more mature fruit was treated. However, the effects of 1-MCP on flesh firmness were similar for apples at mid- or late harvests. 1-MCP treatment of early-harvested fruit of the early-maturing ‘Tsugaru’, which had the highest level of ethylene production and respiration rate, inhibited softening and loss of TA to a greater extent than for late harvested fruit. The same pattern of softening was found for ‘Hongro’ and ‘Fuji’. Firmness of ‘Tsugaru’ and ‘Fuji’ apples was maintained after 8 h treatment with 1.0 µl l^–1 1-MCP, while a 16 h treatment was required for ‘Hongro’. Treatment delays of ≤ 2 d before the application of 1-MCP had no negative impact on fruit firmness. Overall, these results indicate that 1-MCP can be used to maintain the quality of non-refrigerated apples.     

1-MCP对不同成熟度白凤桃冷害发生的影响

以白凤桃果实为材料,研究了1-甲基环丙烯(1-MCP)对低温冷藏条件下果实成熟生理和冷害发生的影响。实验采用25μL/L1-MCP分别对底色转白期(MG)和成熟期(RR)桃果实进行处理,然后置于(0±1)℃冷库中贮藏24d。结果表明,1-MCP处理都能够延缓MG和RR果实的后熟软化进程,降低乙烯释放量,并抑制了果实快速软化阶段的PG酶活性;1-MCP处理提高了贮藏后期MG果实的硬度,降低了出汁率,加剧了冷害的发生程度,1-MCP处理对RR果实的冷害发生率没有显著影响,表明1-MCP对桃冷害的发生程度与果实成熟度有关。     

‘乔纳金’苹果采后1-MCP 处理对常温贮藏效果的影响

 试验结果表明, 1-MCP (1 - 甲基环丙烯) 处理可以明显降低‘乔纳金’苹果果实的呼吸强度,延迟呼吸高峰的出现, 明显减缓硬度和酸度的下降, 减少叶绿素的分解, 但低浓度的1-MCP 处理增加了苦痘病的发生率。     

Interaction of ethylene concentration and storage temperature on postharvest life of the green vegetables pak choi,broccoli, mint,and green bean

Reducing ethylene levels around produce delays the senescence of fruit and vegetables and therefore has the potential to reduce the need for refrigeration during transport and storage, which would result in substantial energy savings. In this study four non-climacteric green vegetables were stored at 0, 5, 10, and 20°C in an atmosphere containing 0.001, 0.01, 0.1, and 1.0 μL L^?1 ethylene. The results showed that the postharvest life, as determined by consumer acceptance criteria of yellowing for pak choi and broccoli, leaf abscission for mint, and pod softening and chilling injury for green bean, increased as the temperature and ethylene concentration decreased. Regression equations generated from the storage data allowed for the calculation of the temperature and ethylene levels required for any nominated postharvest life. Using a 14-day postharvest life as an example, storage in ethylene at 0.001 μL L^?1 would allow a storage temperature of about 10°C for pak choi, broccoli, and mint and about 18°C for green bean, temperatures well above the current recommendations of 0 to 5°C.     

延长黄熟香蕉货架期的研究

实验研究了热水处理、包装自发气调(MAP)、乙烯吸收剂、1-甲基环丙烯(1-MCP)、贮藏温度、多菌灵等对黄熟香蕉货架期的影响。对香蕉的有机酸和总可溶性固形物含量、色差值、包装袋内的CO2浓度进行了测定。结果显示:在(28±2)℃贮藏条件下,黄熟香蕉的货架期只有1d。1-MCP延长黄熟香蕉货架期效果最好,可以延长4d;10%CO2和2%O2的MAP气调和乙烯吸收剂可延长货架期1d;500mg/kg多菌灵48℃热处理浸泡香蕉30s,延长货架期1d。50℃以上高温预处理15min,引起黄熟香蕉热害;pH4.5酸性溶液48℃浸15min,也有明显伤害。48℃高温预处理15min,没有引起伤害。黄熟香蕉对冷害敏感。应用500mg/kg多菌灵浸果30s,晾干后放入0.04mm厚聚乙烯袋内,放入0.8%乙烯吸收剂,换气后初始CO2为10%,O2为2%,袋内注射1-MCP,使最终浓度达0.13mmol/L,可使黄熟香蕉货架期由原来的1d延长到6d。     

Response of kiwifruit (Actinidia deliciosa cv. Allison) to post-harvest treatment with 1-methylcyclopropene

Summary

Experiments were conducted to observe the effect of different concentrations of 1-methylcyclopropene (1-MCP) on the post-harvest life and quality of ‘Allison’ kiwifruit (Actinidia deliciosa). Fruit were treated with 1-MCP at 0.5 µl l^–1, 1.0 µl l^–1, or 2.0 µl l^–1, un-treated fruit served as controls. Each 1-MCP treatment was applied for 24 h at 20°C. After treatment, fruit were transferred to ambient temperature storage (22º ± 4ºC; 65 – 70% relative humidity) for 18 d, during which time observations on various physical, physiological, and biochemical parameters were recorded at 3 d intervals. Our results indicated that 2.0 µl l^–1 1-MCP was the most effective treatment to delay softening and ripening in ‘Allison’ kiwifruit, as such fruit showed the lowest mean weight loss (9.8 ± 0.2%), the highest mean fruit firmness value (32.7 ± 0.2 N), and began to ripen only after 12 d in storage, whereas untreated fruit started ripening on day-6 of storage. The activities of fruit softening enzymes such as polygalacturonase (PG; 58.5 ± 0.3 µg galacturonic acid g^–1 FW h^–1), and lipoxygenase (LOX; 3.96 ± 1.3 µmoles linoleic acid oxidised min^–1 g^–1 FW h^–1) were lower, and total phenolics (TP) contents (24.3 ± 0.3 mg 100 g^–1) and anti-oxidant (AOX) activities (12.5 ± 0.03 µmol Trolox g^–1 FW h^–1) were higher in 1-MCP-treated fruit than in untreated fruit (PG, 98.3 ± 0.5 µg galacturonic acid g^–1 FW h^–1; LOX, 4.39 ± 1.0 µmoles min^–1 g^–1 FW h^–1; TP, 5.3 ± 0.6 mg 100 g^–1; AOX, 4.7 ± 0.02 µmol Trolox g^–1 FW h^–1, respectively). In addition, 1-MCP-treated fruit exhibited lower rates of respiration (48.3 ± 0.4 ml CO₂ kg^–1 h^–1) and ethylene production (30.2 ± 0.02 µl kg^–1 FW h^–1) than untreated fruit (58.9 ± 0.6 ml CO₂ kg^–1 h^–1; 38.7 ± 0.04 µl kg^–1 FW h^–1, respectively). Similarly, 1-MCP-treated fruit had higher titratable acidity (TA; 1.33 ± 0.3%) and ascorbic acid (AA) contents (115.9 ± 2.6 mg 100 g^–1 pulp) and lower soluble solids contents (SSC; 8.33º ± 0.2º Brix) than untreated kiwifruit (TA, 1.0 ± 0.2 %; AA, 105.3 ± 2.2 mg 100 g^–1 pulp; SSC, 13.7º ± 0.3º Brix, respectively). Thus, 2.0 µl l^–1 1-MCP can be used for the post-harvest treatment of ‘Allison’ kiwifruit to enhance its shelf-life and marketability by approx. 6 d.     

Re-initiating softening ability of 1-methylcyclopropene-treated ‘Bartlett’ and ‘d’Anjou’ pears after regular air or controlled atmosphere storage

Summary

‘Bartlett’ and ‘d’Anjou’ pears treated with 300 nl l^–1 1-methylcyclopropene (1-MCP) did not soften to eating quality within 7 d, a desirable ripening period. A pre-conditioning method was evaluated as a means to re-initiate the softening ability of pears prior to marketing. Fruit were treated with 1-MCP and stored at –1°C in regular air, or in a controlled atmosphere for 2 – 9 months. After storage, fruit were pre-conditioned with nine temperature (10°, 15° or 20°C) and time (5, 10 or 20 d) combinations. Pre-conditioned fruit were then assessed for ripening ability following storage for 14 d at 20°C. The ripening ability of 1-MCP-treated ‘Bartlett’ fruit recovered in response to many pre-conditioning combinations of 10° – 20°C for 10 – 20 d, as indicated by a decrease in flesh firmness to 27 N or lower. The requirements for pre-conditioning regimes are storage atmosphere- and time-dependent. For ‘d’Anjou’ pears, no pre-conditioning combination resulted in re-initiating the ripening of fruit treated with 300 nl l^–1 1-MCP. However, when the 1-MCP dose was 50 nl l^–1, ‘d’Anjou’ pears ripened over an extended shelf-period with a substantial decrease in superficial scald. The results indicate that treatment with 1-MCP at approx. 50 nl l^–1, combined with a pre-conditioning prior to marketing, is a potential means to control scald in ‘d’Anjou’ fruit. Re-initiation of ripening occurred concomitantly with a substantial increase in ethylene production. The control of superficial scald by 1-MCP in ‘d’Anjou’ pears was due to the inhibition of the biosynthesis of -farnesene and conjugated trienes.     

Grafting effects on postharvest ripening and quality of 1-methylcyclopropene-treated muskmelon fruit

In addition to managing soil-borne diseases in muskmelon (Cucumis melo L.) production, grafting with resistant rootstocks may impact fruit quality. The ethylene antagonist 1-methylcyclopropene (1-MCP) has been shown to extend shelf life of fresh muskmelon fruit. Postharvest characteristics of 1-MCP-treated melon fruit as affected by grafting, however, have not been well examined. This study was conducted to explore the influence of grafting with different rootstocks on ripening and quality attributes of 1-MCP-treated muskmelon fruit during postharvest storage. Grafted ‘Athena’ muskmelon with two commercial squash interspecific hybrid rootstocks including ‘Strong Tosa’ and ‘Tetsukabuto’ as well as non-grafted and self-grafted ‘Athena’ were grown in replicated field plots at the University of Florida Plant Science Research and Education Unit (Citra, FL, USA) during April–June 2010. Half-slip fruit from two harvests were treated with 1.0 μL L⁻¹ 1-MCP (18 h, 20 °C) and analyzed during storage at 13 °C. For fruit from the 27 May harvest, whole fruit and mesocarp firmness, titratable acidity, soluble solids, and ascorbic acid content were measured, while production of ethylene and CO₂ was determined on fruit from the 29 June harvest. Grafting did not show a significant impact on fruit yield but affected the fruit shelf life significantly. Fruit from non-grafted ‘Athena’ and ‘Athena’ grafted onto ‘Strong Tosa’ demonstrated a shelf life of 31 d for the first harvest and 22 d for the second harvest. Shelf life of fruit from self-grafted ‘Athena’ and ‘Athena’ grafted onto ‘Tetsukabuto’ declined by 6 d and 3 d for the first and second harvest, respectively. Whole fruit firmness decreased by approximately 15.5% on average from 13 to 31 d except day 19 as a result of grafting, but to a lesser extent with ‘Strong Tosa’ rootstock. Mesocarp firmness of grafted melon was reduced by about 30.2% at days 13 and 19 compared to non-grafted ‘Athena’ fruit. In contrast, titratable acidity, soluble solid content, and ascorbic acid concentration were less affected by grafting. All the measurements except for ethylene and CO₂ production declined during storage regardless of the grafting treatment. Compared with ‘Strong Tosa’ rootstock, ‘Tetsukabuto’ resulted in a more rapid ripening under 1-MCP application, as reflected by earlier increase in ethylene production and higher respiratory rate. The study demonstrates that grafting effects on postharvest ripening and quality of ‘Athena’ muskmelon can vary markedly with rootstocks used.     

The influence of exogenously applied 2,4-D and NAA on fruit drop reduction in pummelo cv. Thong Dee

ABSTRACT

Effect of 2,4-D and naphthalene acetic acid (NAA) on fruit drop reduction in pummelo cv. Thong Dee was investigated in the pummelo growing areas of Nakhon Pathom province, Thailand. Five similar sized and aged of pummelo trees were selected to set up the experiment. Ten mature branches with the same size from each pummelo tree were randomly selected around the canopy for 2,4-D (20 and 40 mg L^?1), NAA (20 and 40 mg L^?1) application and control. All treatments were applied to selected pummelo branches 2 times at full bloom and 2 months after fruit set. The results showed that 20 mg L^?1 NAA (14.84%) and 40 mg L^?1 NAA (12.26%) gave significantly higher percent of fruit retention at 6 months after fruit set. However, leaf total nonstructural carbohydrate concentration analysis showed that 40 mg L^?1 2,4-D (104.86 mg g^?1) and 20 mg L^?1 2,4-D (96.55 mg g^?1) gave significantly higher total nonstructural carbohydrate than those in control (78.44 mg g^?1). For fruit quality, 40 mg L^?1 2,4-D and 20 mg L^?1 2,4-D gave the highest peel weight with 435.55 and 358.57 g, respectively, and 40 mg L^?1 2,4-D gave the highest peel thickness with 20.25 mm, while 20 mg L^?1 NAA gave statistically higher total soluble solid than those in 20 mg L^?1 2,4-D and 40 mg L^?1 2,4-D. Therefore, 20 mg L^?1 of NAA sprayed 2 times at full bloom and 2 month after fruit set effectively reduced fruit drop and increased percentage of fruit retention in pummelo cv. Thong Dee.     

In vitro Germination of Early Ripening Sweet Cherry Varieties (Prunus avium L.) at Different Fruit Ripening Stages

In vitro embryo culture enabled satisfactory germination of immature seeds produced in crosses from early ripening sweet cherry varieties (Prunus avium L.). Three varieties —‘Rita’, ‘Bigarreau Burlat’ and ‘Carmen’— were crossed with ‘Early Star’ as male parent. Germination rate was affected by the developmental stage of both fruit and embryo. Fruit ripening stage was a critical factor for culture infection rate that increased with maturity. In-ovule embryo culture on Murashige and Skoog medium without hormones improved the embryo size but did not increase the germination rate due to a further increase in infection rate. Ex-ovule embryo culture on Murashige and Skoog medium supplemented with BA 1 mg L^?1, NAA 0.5 mg L^?1, 20 g L^?1sucrose, 10 g L^?1 sorbitol and 6 g L^?1agar during the stratification time increased embryo length. Germination was performed on Brooks and Hough medium at the 22?±?1?°C with 16/8 h light/dark photoperiod. The highest germination rate (75?%) was reached in embryos that were 3?4 mm in length, after 30-days stratification at 4?°C. Embryos in fruits at green-yellow stage that were 3?4 mm long were morpho-physiologically developed to produce bipolar seedlings, without combined application of embryo culture and micropropagation.     

Influence of 1-methylcyclopropene on pectic enzyme activities,gene expression,and cell wall modification in papaya (Carica papaya cv. ‘Sunrise’) fruit

SUMMARY

‘Sunrise’ papaya fruit harvested at two stages of maturity [colour break (< 10% yellow peel colour) and 25% yellow peel colour] were treated with 100 nl l^–1 1-methylcyclopropene (1-MCP) to determine its effects on ripening, on the activities and levels of gene expression of polygalacturonase (PG), pectin methyl esterase (PME), and βgalactosidase ( βGal), and on the degradation of cell wall components. 1-MCP delayed ripening and the onset of the climacteric, although the peak in the respiration rate was almost the same as that in untreated control fruit. Colour-break fruit treated with 1-MCP exhibited a continuous increase in ethylene production, but at a lower rate than in control fruit. Consequently, 1-MCP-treated fruit ripened with a concomitant reduction in firmness, which was accompanied by an increase in PG and βGal enzyme activities and gene expression. On the other hand, fruit treated with 1-MCP at the 25% yellow stage exhibited lower levels of ethylene production and developed pulp with a rubbery texture at the ripe stage which was attributed to reduced PG, βGal, and PME enzyme activities and gene expression. This was consistent with the higher level of cell wall polysaccharides measured in 1-MCP-treated fruit. The above results indicated that ‘Sunrise’ papaya fruit can be treated with 1-MCP at the colour break stage since they have a greater capacity to recover from the effects of 1-MCP than fruit treated at the 25% yellow stage.     

采后1-MCP和热处理对红富士苹果生理变化和贮藏品质的影响

采用1-MCP(浓度为1μL/L,18h)、热空气(HA)38℃-96h及2者结合对富士苹果进行处理,处理后的果实置于(0±0.5)℃条件冷藏4个月,然后置于20℃条件下7d(模拟货架期)。试验发现在整个贮藏过程中所有处理组均能抑制果实的乙烯释放速率和呼吸强度,减缓果实硬度的降低。热处理组对固酸比的上升有显著作用,保持了较高的非水溶性果胶含量和较低的水溶性果胶含量。热处理在贮藏过程中对于果实硬度的保持与对照组相比起到一定的作用,但加速了果皮中叶绿素含量的降解。1-MCP处理组能够较好地抑制果实果皮的褪绿,保持果皮中较高的叶绿素含量,初期抑制细胞膜透性的上升,延缓果实的后熟衰老。结合处理组较好地保持果实膜的完整性,减缓了由热处理所引起的果皮叶绿素的降解,并保持较高的含酸量,保持了较好的风味品质。     

柿果实1 - 甲基环丙烯处理对成熟软化的影响

 研究了乙烯受体抑制剂1 - 甲基环丙烯(1-MCP) 处理对火柿果实成熟的影响。结果表明: 1-MCP 处理能显著抑制果实乙烯释放, 延缓其跃变出现时间, 推迟ACO (ACC 氧化酶) 活性峰及呼吸跃变,抑制采后初期ACO 的活性及呼吸速率的上升, 并能阻止硬度的下降, 推迟其成熟软化, 延长贮藏期。