By using eight-year-old early maturing peach cultivar 'Hikawa Hakuho' (Prunus persica Batsch) trees grafted on wild form peach rootstocks, which were trained as a central leader, effects of pinching on shoot and fruit growth, fruit drop, yield, fruit weight and fruit quality were examined. In the pinching treatment, all current shoots longer than 20cm were pinched to 20cm at weekly intervals from May 18 to June 29, whereas the shoots of control trees were unpinched. The replications were four. The pinching treatment reduced the total shoot length and the number of long shoots and thus the percentage of short shoots were increased. Fruit growth was slightly reduced by pinching, resulting in smaller fruit weight compared with control. Both Brix and titratable acidity of harvested fruit were lower in the pinched trees than control trees. Pinching lowered the percentage of fruit drop. A positive correlation between total shoot length and yield was apparent in the pinched trees, but not in the control trees.

The effects of tree water stress on sweet cherry (‘New Star’) fruit quality during post-harvest and pre-harvest fruit thinning were evaluated in a 2-year field experiment (2005 – 2006). Four different treatments were applied: (i) fully irrigated (Control), in which irrigation was scheduled according to a water budget approach; (ii) RDI-80%, in which the crop received 0.8× Control irrigation during post-harvest and was irrigated like the Control during pre-harvest; (iii) RDI-50% in which the crop received 0.5× Control irrigation during post-harvest and was irrigated like the Control during pre-harvest; and (iv) RDI-80%-T in which irrigation management was the same as for RDI-80%, but fruits were only thinned 1 month prior to harvest in 2006. No significant effects on fruit load or yield were observed in 2006 as a consequence of the 2005 irrigation treatments. However, the RDI-50% treatment produced a noticeable advance in ripening, as evaluated from the percentage of fruit harvested at the first pick. Post-harvest water stress did not affect fruit quality at harvest, but slightly reduced fruit firmness (FF) and soluble solids content (SSC) after cold storage, with no significant variation in fruit flesh red colour (expressed as hue angle). Fruit-thinning reduced the fruit load by 38% compared to Control trees, and significantly increased fruit fresh weight (FW), FF, and SSC for cherries with similar flesh colour to the other treatments. Reducing irrigation by 50% during post-harvest advanced the harvest date (RDI-50% treatment), but did not provide any advantage in terms of fruit quality.

BACKGROUND: Decay caused by fungal pathogens is responsible for significant economic loss of grape fruit in vineyards worldwide. However, postharvest treatment is not advisable for this fruit owing to its thin waxy pericarp and succulent flesh, which are easily damaged. Therefore preharvest treatment even at 1 day before harvest has been considered as a promising method to control postharvest decay of table grape fruit in storage. Integrative effects of preharvest application of Cryptococcus laurentii combined with low-concentration chitosan on decay and quality of table grape fruit during storage were investigated in this study.RESULTS: Spraying of antagonistic yeast combined with chitosan before harvest significantly reduced natural decay of fruit stored at 0 °C. Preharvest treatment stabilised polyphenol oxidase activity, increased peroxidase and phenylalanine ammonia-lyase activities and decreased superoxide dismutase activity compared with control fruit. There was a higher ratio of soluble solid content to titratable acidity in treated fruit than in control fruit during storage. In addition, preharvest treatment affected the total phenolic content in fruit during storage.CONCLUSION: The results suggest that integrative application of C. laurentii and low-concentration chitosan before harvest may be a promising technology to control decay of table grape fruit in storage.

The eating quality of banana fruit is maintained high for only a short time between the firm-ripe stage and fully ripe stage. To clarify the efficacy of 1-methylcyclopropene (1-MCP) treatment on maintaining the quality of banana fruit at these stages, we investigated the effects of timing of 1-MCP treatment on fruit quality during ripening. Mature green banana fruit were treated with or without 1-MCP at 1, 2, 3, 4, or 5 days after the start of ethylene treatment (DASE) and stored at 20degC in the dark. The peel color of banana fruit treated with 1-MCP at 2, 3, 4, and 5 DASE typically turned yellow in a manner similar to that of the control fruit. In fruit treated with 1-MCP at 1 and 2 DASE, the development of brown spots was significantly suppressed. At 6 DASE, there was no difference in flesh firmness between the control fruit and that treated with 1-MCP at 2 DASE, which means that 1-MCP-treated fruit typically softened up to the firm ripe stage. The firmness of 1-MCP-treated fruit was then maintained, while that of the control fruit decreased. There was no difference in the soluble solid content between 1-MCP-treated fruit and the control fruit. The findings revealed that 1-MCP treatment of banana fruit at 2 DASE prolongs the period between the firm-ripe stage and fully ripe stage with no negative impact.

Chilling of avocado fruit (Persea americana cv. Arad) in the orchard caused a dramatic induction of fruit ripening and a parallel increase in ethylene biosynthesis and receptor genes' expression during shelf life. In-orchard chilling stress stimulated ethylene and CO2 production already in fruit attached to the tree, and these reduced thereafter during 20 °C storage. In non-chilled control fruit, ethylene and CO2 production started after 3 d at 20 °C and exhibited a climacteric peak. In-orchard chilling stress also led to membrane destruction expressed as higher electrical conductivity (EC) in chilling stressed (CS) fruit and accelerated softening compared with control fruit. The increase in ethylene production on the day of harvest in CS fruit was accompanied by high expression of two 1-aminocyclopropane-1-carboxylic aCSd (ACC) synthase genes: PaACS1 and PaACS2, and ACC oxidase PaACO. The initial gene expressions of PaACS1, PaACS2, and PaACO in the CS fruit at the day of harvest was similar to the levels reached by the control fruit after 4 d at 20 °C. The expression levels of both PaETR and PaERS1 in CS fruit on tree were 25 times higher than the control. In control fruit, expression of ethylene receptor genes was very low at harvest and increased in parallel to the onset of the climacteric ethylene peak. PaCTR1 transcript levels were less affected by chilling stress, and small changes (less than 3-fold) were observed in CS fruit on the day of harvest. Together, our results suggest that ethylene biosynthesis and ethylene response-pathway genes are involved in regulation of ethylene responsiveness in response to in-orchard chilling stress and during ripening.

Preharvest fungicide applications for postharvest control of Botrytis fruit rot were evaluated over four seasons on annual strawberry in Florida. In the 2002-2003 season, applications of Switch or Elevate immediately prior to harvest were ineffective for controlling Botrytis fruit rot postharvest. In the 2003-2004 season, applications of Captevate or Switch made immediately prior to harvest reduced postharvest Botrytis fruit rot, but not as much as applications made during the flowering period. Similarly, in the 2004-2005 season, Captevate and Pristine provided some control of postharvest Botrytis fruit rot when applied immediately before harvest. In both the 2003-2004 and 2004-2005 seasons, applications made during the flowering period were more effective for postharvest Botrytis fruit rot control than those made prior to harvest. In the 2006-2007 season, applications of Captevate, Thiram, Scala plus Captan, or Switch alternated with Captan during the flowering period provided good control of postharvest Botrytis fruit rot. Although not as effective as bloom applications, fungicides applied immediately before harvest may have some benefit for controlling Botrytis fruit rot if the sprays during the bloom period were not made.

A study was carried out to determine the effects of different mulch materials on plant growth, some quality properties and yield in melon cultivars in high altitude environmental condition. Clear mulch application affected more plant growth than the other applications. Fruit width, fruit length, dry matter in fruit, total soluble solid, color, husk thickness, fruit fresh thickness, fruit firmness, pH, total and reducing sugar of the cultivars were investigated. The effects of mulch application in terms of the characters were significant depending on the cultivars. Average fruit weight of the cultivars was significantly high in mulch application, especially clear mulch application when compared to control. Marketable yield in melon cultivars was different based on the years. The highest marketable yield was obtained from clear mulch application as compared to control. Average marketable yield in the study years increased by 25-28% in clear plastic mulch and 15% in black plastic mulch compared to the control application. Soil temperature in clear and black mulch applications were higher (5-8 degree C and 1-4 degree C respectively) than that of control application.