The effect of red-and blue-light-emitting diodes on shoot and root growth of Hybrid Franc grape, a rootstock cultivar, along with two other grape genotypes, Kadainou R-1 and Vitis ficifolia var. ganebu, were investigated in vitro. Plants cultured under red-light-emitting diodes produced the longest shoots with longer internodes for all genotypes. The chlorophyll content measured as SPAD value and leaf number per explant were highest on plants cultured under blue-light-emitting diodes in all the genotypes. Blue light was also responsible for a higher number of stomata in all the genotypes; however, there was no significant difference in size of stomata in all genotypes under the different light conditions tested. Different light-emitting diodes did not affect the rooting percentage of Hybrid Franc but red-lightemitting diodes gave a higher rooting percentage along with higher root numbers for the two other grape genotypes.

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High temperature affects berry composition, especially titratable acidity, total soluble solids, and anthocyanin content. Vitis ficifolia var. ganebu, a wild grape of sub-tropical origin with a low chilling trait, develops good coloration in its natural habitat, where daytime and nighttime temperatures are high during the berry ripening stage, while V. vinifera 'Muscat of Alexandria', a table grape, has large berries and high sugar content, hence, it was hypothesized that hybridizing V. ficifolia var. genebu with V. vinifera would improve the sugar content and reduce titratable acidity compared to V. ficifolia var. ganebu and retain berry color even under high temperature conditions. The aim of this study was to investigate the influence of temperature on the berry composition of 'Kadainou R-1', an interspecific hybrid wine grape derived from V. ficifolia var. ganebu × V. vinifera 'Muscat of Alexandria'. Potted 'Kadainou R-1' vines with their ownroots were subjected to continuous temperatures of 20, 25, and 30°C in a phytotron during the berry-softening stage. Berries were harvested 15, 30, and 37 days after the vines were placed in the phytotron. Titratable acidity was lower at 30°C than at 20°C, while total soluble solids were highest at 25°C. Accumulations of glucose and fructose were higher at low rather than high temperatures. Total anthocyanin content (mg·g −1 of fresh weight) was significantly reduced at 20 and 30°C but not at 25°C. Flavonol content was highest at 25°C. The present study revealed that 'Kadainou R-1' grapes can produce optimum berry quality in locations where the night temperature reaches 25°C without significant loss in berry quality.

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L(xluat fruits (cv. Mogi) were harvested at three stages of ripeness (less-ripe, ripe, and full-ripe) and stored at 5'C to determine the optimal harvest ripeness for storage. During low-temperature storage, the weight of loquats at all three ripeness stages was decreasedj whereas the weight losses showed no significant difference with ripeness.The decay of less-ripe fruit was worse than that of ripe and full-ripe fruits. Loquats underwent a significant decrease in titratable acidity (TA), malic acid and sucrose contents, while total sugars (TS), polyphenols, citric acid, succinic acid and fumaric acid contents did not vary greatly and resulted in a significant increase in TS/TA ratios during storage at 5'C. Development of skin color and carotenoids occurred progressively during the first 30 days of storage at 5'C and then did not vary significantly. Fructose and glucose contents of loquats increased during the first 30 days but after that appeared to decrease slightly. The sorbitol content of loquats increased steadily, while galactose decreased to a trace level during storage. Based on the data from this study, harvest ripeness greatly affected the quality of loquats at harvest as well as during storage. Ripe fruit showed superior storage capacity compared to fruits harvested at less-ripe and full-ripe stages. Keywords:loquat, Eriobotrya japonica LINDL., harvest ripeness, cold storage, quality, fruit compositionThe quality of loquats is highly dependent on the degree of ripeness (Uchino et al, 1994). Loquats harvested in the fully ripe stage have the optimum quality; therefore, they are left on the tree until fully ripe unless they are to be used in jellies or for cooking (Shaw, 1980). However, in commercial situations where transport and shelf-life are involved, Ioquats are generally harvested at the eating-ripe stage before becoming fully ripe, which may result in reduced quality of the fruit.The effects of storage temperature on different loquat cultivars have been reported (Mukerjee, 1958;Shaw, 1980;Shinbori & Nakai, 1991). Cold storage of loquats will retard senescence and lengthen storage life. However, there was no indication regarding at what stage of ripeness loquats should be harvested to maintain high quality after storage.The appearance of skin color and contents of polyphenols, sugars and organic acids are the key components that contribute to a high quality of fresh loquat. However, Iittle information is available in the literature on those parameters during low-temperature storage. The objective of this study was to characterize the postharvest physical and chemical changes in loquat fruits in relation to ripeness at harvest. Materials and MethodsPlant materials The loquat (Eriobotrya japonica LINDL. cv. Mogi) fruits were obtained from the affiliated teaching farm of the College of Agriculture, Osaka Prefecture University, Osaka, Japan. The fruits were hand-picked and sorted into less-ripe, ripe and full-ripe stages (Table l) according to fruit surface color and the Hunter a values of '' ,, th...

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