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Role of ethylene receptors during senescence and ripening in horticultural crops

“…80 Lower transformation efficiency along with diminished disease resistance and lower ethylene sensitivity 48,81 was observed using constitutive promoter compared with flower specific promoters, which took care of both the above stated drawbacks. 79,82 Symptoms like petal in rolling phenotype, hallmark of ethylenedependent carnation flower senescence was not observed in transgenic carnation flowers. Instead, the petals remained firm throughout the senescence process and gradually became brown on the edges (loosing color) and died from rotting.…”

“…However, some cultivars of Chrysanthemum are ethylene sensitive. Narumi et al (2005a) 84 observed that in an ethylene insensitive cultivar of Chrysanthemum the DG-ERS1 transcript level was highest and declined consistently thereafter. The same was not observed in an ethyleneinsensitive cultivar, though.…”

“…Instead, the petals remained firm throughout the senescence process and gradually became brown on the edges (loosing color) and died from rotting. 79 Transgenic carnation cut flowers had three times the vase life of non transformed flowers and lasted longer than flowers treated with inhibitors of ethylene biosynthesis or ethylene antagonists. 79,80 Catharanthus.…”

“…79 Transgenic carnation cut flowers had three times the vase life of non transformed flowers and lasted longer than flowers treated with inhibitors of ethylene biosynthesis or ethylene antagonists. 79,80 Catharanthus. The ETR1 gene deciphered in Catharanthus roseus showed highest transcript levels in petals and ovaries.…”

Ripening in the tomato Green-ripe mutant is inhibited by ectopic expression of a protein that disrupts ethylene signaling

“…Control of ethylene responsiveness in crops is of commercial importance to reduce senescence, overripening, and postharvest deterioration of fruit, vegetable, and floral crops. Previous research has led to the generation of transgenic horticultural crops with altered ethylene responsiveness to counteract the negative impacts of ethylene on ripening and floral senescence (52,53). These studies have successfully achieved their aims, but subsequent evaluation of horticultural performance has revealed that constitutive ethylene insensitivity mediated by a dominant gain of function receptor mutation has deleterious effects on seed germination, seedling vigor, and adventitious rooting in tomato and petunia (46,54,55).…”