A natural lipid, lysophosphatidylethanolamine (LPE), was used as a tomato fruit ripening agent. The effect of this compound on hastening the ripening and on the defoliation of the `Heinz 7155' processing tomato and the Glamour fresh-market tomato (Lycopersicon esculentum Mill.) was compared to the effect of ethephon. Vines were sprayed to runoff in the field with a hand sprayer and fruits were harvested 2 weeks or 20 days later in a single harvest operation. LPE (100 mg liter-1) accelerated ripening of both processing and fresh-market tomatoes without defoliation. LPE-treated tomatoes had a better shelf life than the control or ethephon-treated fruit, whether they were harvested at the breaker, pink, or red stage of maturity. The combination of LPE and ethephon (100 mg liter-1) enhanced tomato ripening without damaging the foliage, suggesting that LPE can mitigate the undesirable effects of ethephon on foliage and the fruit. The LPE-related lipid phosphatidyldimethylethanol-amine dipalmitoyl (PDED) also was able to enhance some aspects of keeping quality of tomato fruits, but was not able to enhance fruit ripening. Phosphatidylethanolamine was not as effective as LPE or PDED. It appears that the active molecule of this natural lipid is the lyso form. Our results provide evidence that LPE can enhance tomato fruit ripening and postharvest storage life of vine-ripe fruits and fruits picked at early ripeness stages.
Karim M. Farag and Jiwan P. Palta
Smit le Roux and Graham H. Barry
genotypes tested by ≈40%. In contrast to the affects of gibberellin-biosynthesis inhibitors on vegetative growth, their effects on rind color enhancement of citrus fruit are not well known. Monselise and coworkers (1976) reported that paclobutrazol
Bert M. Cregg and Robert Schutzki
(pine bark, cypress mulch, hardwood mulch, and color-enhanced ground recycled pallets) over 3 years. We chose to focus on organic mulches because their superiority over inorganic mulches has been well documented in the literature ( Chalker-Scott, 2007
W.S. Lee, J.C. Lee, and Y.S. Hwang
The coloration of grape berries depends on the anthocyanin synthesis during maturation. The quality of berries is often decreased due to the poor color development when berries are grown under unfavorable environments and/or inadequate internal factors are involved. It has been well-known that the level of ABA at ripening is closely associated with anthocyanin synthesis; thus, the external application of ABA results in the increase of anthocyanin content even in berries grown under favorable conditions. However, the agricultural use of natural ABA is not possible because of high prices. This experiment was conducted to study the potential of STC-4771 as a substitute for ABA. The effect of STC-4771 was studied in `Kyoho', `Pione', and `Delaware' grapes. Chemicals were applied when ≈10% of berries in a cluster were colored. In `Kyoho', anthocyanin synthesis was enhanced at a concentration of 100 mg/L and there was a trend in color enhancement in `Pione', regardless of treatment concentration, between 10 to 40 mg/L. However, no clear effect was found in `Delaware' at 50 to 100 mg/L. In an in vitro experiment, anthocyanin was only increased when an adequate amount of sucrose (0.6 m) was added in the incubation medium under light. Natural ABA effectively increased the anthocyanin content of berry segments even under shading condition through four bagging materials, but no effect was confirmed in STC treatment.
C. Larrigaudiere, E. Pinto, and M. Vendrell
The differential effects of two color improving products, ethephon an ethylene-releasing compound, and seniphos, a nonethylene-releasing product, were studied on `Starking Delicious' apples (Malus domestica Borkh L.). Ethephon and seniphos were applied 2 or 3 weeks before commercial harvest. Ethephon- and seniphos-treated fruit showed a significant improvement of peel color associated with a sharp increase in anthocyanin content and chromaticity values. Color improvement in ethephon-treated apples occurred during the preharvest period and cold storage. The seniphos-treated fruit stopped color development in cold conditions. In comparison to the ethephon-treated fruit, the seniphos-treated apples showed lower internal ethylene concentrations and a ripening delay. Both treatments sharply increased the activity of phenylalanine-ammonia-lyase enzyme, which seemed to be the determining factor of color enhancement. The seniphos-treated apples compared to ethephon had higher fruit firmness and lower soluble solids concentrations. Anthocyanin biosynthesis may be enhanced by seniphos treatment without inducing ethylene production or other ripening associated changes. As a consequence, fruit treated with seniphos can be held longer in storage.
Graham H. Barry and Smit le Roux
significantly reduced shoot growth and increased fruit size in pears ( P. communis L.). In contrast to the affects of gibberellin-biosynthesis inhibitors on vegetative growth, their effects on rind color enhancement of fruit of Citrus spp. have not been
Xiuxiu Sun, Elizabeth Baldwin, Mark Ritenour, Robert Hagenmaier, and Jinhe Bai
searching for a CR2 alternative found that several oil-soluble natural colorants were comparable to CR2 as a color enhancer ( Sun et al., 2015 ). However, postdye waxing was considered a necessity to reduce oxidation of carotenoid colorants ( Sun et al
Emily C. Baisden, Douglas W. Tallamy, Desiree L. Narango, and Eileen Boyle
. Cultivar traits examined include altered leaf color, disease resistance, enhanced fall color, enhanced fruiting, altered growth habit, and leaf variegation. Error bars = 95% confidence intervals; bars below zero have more species on cultivars; bars above
Mark E. Uchanski and Adam Blalock
.W. 1989 Heat units. Univ. Ariz. Coop. Ext. College Agr. Bul. 8915 Cantliffe, D.J. Goodwin, P. 1975 Red color enhancement of pepper fruits by multiple applications of ethephon Amer. Soc. Hort. Sci. 100 153 157 Funk, P.A. Marshall, D.E. 2012 Pepper harvest
Derek W. Barchenger, Danise L. Coon, and Paul W. Bosland
.J. Goodwin, P. 1975 Red color enhancement of pepper fruits by multiple applications of ethephon J. Amer. Soc. Hort. Sci. 100 153 157 Davis, K. Stover, E. Wirth, F. 2004 Economics of fruit thinning: A review focusing on apple and citrus HortTechnology 14 282