บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Endogenous Factors Influencing Decay Susceptibility and Quality of ‘d’ Anjou ‘ Pear (Pyrus communis L.) Fruit During Maturation and Storage

Danai Boonyakiat

Thesis of Doctor of Philosophy in Horticulture Oregon State University, 1984, 134 pages.

1984.

บทคัดย่อ

Endogenous Factors Influencing Decay Susceptibility and Quality of ‘d’ Anjou ‘ Pear (Pyrus communis L.) Fruit During Maturation and Storage The major phenolics of ‘d’ Anjou’ pear (Pyrus communis L.) tissues were chlorogenic acid and arbutin. Chlorogenic acid inhibited mycelial growth and spore germination of Penicillium expansum and mycelial growth of Mucor piriformis. Slight increases in radial growth and spore germination of Botrytis cinerea occurred o­n chlorogenic acis\d media. Chlorogenic acid had no effect o­n M. piriformis spore germination. Arbutin inhibited spore germination of P. expansum, and inhibited both mycelial growth and spore germination of M. piriformis and B. cinerea. The effect of arbutin o­n radial growth of P. expansum was not significant.

Decay susceptibility of ‘d’ Anjou pear fruit increased as fruit approached maturity. Ethanol extracts from the fruit increased radial growth of the fungi, but had no effect o­n spore germination. Fruit firmness and polygalacturonase inhibitor activity correlated significantly with percent decay. The relationship between phenolics and fruit decay was not significant. The location of fruits o­n the trees had no effect o­n decay, firmness, fungal radial growth, fungal spore germination, polygalacturonase inhibitor activity and amount of phenolics.

Late maturing ‘d’ Anjou’ pear fruits were more susceptible to storage decay than the pre – and optimum mature fruits. Immature fruit was firmer than optimum and late mature fruit at harvest and throughout the storage period. Extractable juice(EJ) of unripened fruit was maintained at a constant level throughout the storage period. EJ of ripened fruit declined substantially, but gradually increased after late sampling pariod. Soluble solids (SS) varied among different harvest groups and during the storage period. Fruits increased SS upon ripening. Immature fruits had higher titrable acids (TA) than optimum and late mature fruit. TA decreased during the storage period and also upon fruit ripening. Superficial scald developed o­n the ripened fruit in December, 1982 and increased thereafter. Immature fruits showed higher incidence of scald development than the optimum and late mature fruit in December, but all fruits developed scald symptoms after February, 1983. Optimum mature late mature fruit developed acceptable flesh texture, and flavor upon ripening until February, 1983. Immature fruit was incapable of developing an acceptable flavor upon ripening throughout the sampling period.