Ethylene production, shelf-life and evidence of RFLP polymorphisms linked to ethylene genes in melon (Cucumis melo L.).
Zheng, X. Y.; Wolff, D. W.;
Theoretical and Applied Genetics Year: 2000 Vol: 101 Issue: 4 Pages: 613-624 Ref: 42 ref.
2000
บทคัดย่อ
Sixty three cultigens from eight market types of the melon (Cucumis melo subsp. melo) groups Cantaloupensis and Inodorus were evaluated for ethylene production rate, shelf-life (postharvest decay) and RFLP polymorphisms. The ethylene production rates of melon fruits at maturity and (after) postharvest decay were measured on individual genotypes. The ethylene production rates of individual genotypes ranged from undetectable to 103 nl/g per h. The mean ethylene production rates of the eight market types, ranked from highest to lowest, were Eastern US type, Charentais, Western US type, Long Shelf-Life cantaloupes (LSL), Galia, Ananas, Honeydew, and Casaba. Ethylene production and postharvest decay rating were positively and significantly correlated. Orange-fleshed melon fruits produced significantly more ethylene than did green- or white-fleshed types. Melon fruits with a netted rind had significantly (P=0.05 for orange-flesh fruits and 0.01 for green- or white-flesh fruits) higher ethylene product
ion than did smooth-type fruits. Using probes made from cDNAs encoding ACC oxidase (MEL1) or ACC synthase (MEACS1) genes, RFLPs were detected in melon cultigens of the eight marker types showing varying ethylene production rates and different flesh colors. Low ethylene production and green- and white-flesh colour were associated with the presence of a putative RFLP-MEL1 allele A0 (15-kb), whereas high ethylene production and orange-flesh colour were associated with allele B0 (8.5-kb) in the homozygous condition, after probing MEL1 with EcoRV-digested genomic DNA. Also, after probing MEACS1 with NdeI-digested genomic DNA, RFLP polymorphism revealed five fragments denoted as A, B, C, D and E, with molecular sizes of 5.2-, 4.2-, 3.8-, 3.0- and 1.0-kb, respectively. A two-fragment pattern, AB, and a three-fragment pattern, ACE, the two predominant RFLP patterns, were also associated with low and high ethylene production, respectively. The ACE fragment pattern was also associated with orange-flesh melons. Scoring
of both probes allowed for the unique classification of most melon market types consistent with ethylene production and the postharvest decay phenotypes. Therefore, these RFLPs might have utility in marker-assisted selection for the development of melons with enhanced postharvest keeping ability.