regulating cytoplasmic acidity, glucose use, nitrogen storage, plant development, plant defense, and fruit ripening ( Bown and Shelp, 1997 ; Gallego et al., 1995 ). Although GAD and its product GABA have been identified in legumes decades ago, their
Wei Hu, Ju-Hua Liu, Xiao-Ying Yang, Jian-Bin Zhang, Cai-Hong Jia, Mei-Ying Li, Bi-Yu Xu, and Zhi-Qiang Jin
Shaolan Yang, Changjie Xu, Bo Zhang, Xian Li, and Kunsong Chen
Fruit textural change is one of main processes that occur during fruit ripening and senescence. It affects the postharvest life of fruit as well as fruit quality and commercial value. Softening is a comprehensive result of complex primary cell
Roisin McGarry, Jocelyn A. Ozga, and Dennis M. Reinecke
Field experiments were conducted on two cultivars of saskatoon to test the effectiveness of ethephon in stimulating uniform fruit ripening without compromising fruit quality. Shrubs of cultivars Northline and Smoky were sprayed to runoff with ethephon (0, 250, 500, and 1000 mg·L-1 for `Northline'; 0, 500, and 1000 mg·L-1 for `Smoky') prior to fruit maturity. Fruit were harvested 4 to 8 days after treatment and sorted into ripeness categories by size, and the fully ripe fruit were evaluated for quality (surface color, firmness, mean fruit weight, soluble solids, and titratable acids). Ethephon significantly increased the percent ripe fruit per shrub (by up to 9.7%) in both cultivars, without a significant effect on fruit quality. At concentrations up to 1000 mg·L-1, ethephon may be an effective ripening agent for saskatoon fruit without reducing fruit quality. Although there were significant differences in yield from year to year for both cultivars because of their biennial-bearing habit, ethephon treatments did not significantly affect total yields.
Sang-Dong Yoo, Zhifang Gao, Claudio Cantini, Wayne H. Loescher, and Steven van Nocker
A preliminary understanding of developmental processes among divergent species is essential to evaluate the applicability of information from model species to plants of agricultural importance. In tomato (Lycopersicon esculentum Mill.), where the molecular biology associated with fruit ripening has been studied most extensively, tissue softening is due at least in part to the activity of proteins called expansins, in concert with enzymatic activities that modify the pectin and xyloglucan components of the cell wall. We evaluated the potential for the concerted action of expansins and other cell wall-modifying enzymes during ripening in a highly divergent fruit species, sour cherry (Prunus cerasus L.). We identified a family of four expansin genes that was strongly upregulated at the advent of ripening. Activation of these genes was accompanied by strong upregulation of gene(s) encoding potential pectin methylesterases, pectate lyase(s), and xyloglucan endotransglycosylase(s). Initiation of ripening and gene induction were also associated with a rapid decrease in cell wall weight. These results suggest that expansin and several other distinct activities could be involved in ripening-associated cell wall modification in cherries.
Xiaohong Wang, Bishun Ye, Xiangpeng Kang, Ting Zhou, and Tongfei Lai
Fruit ripening is an important stage for plants bearing fleshy fruit. During the process of ripening, there are noticeable changes in biophysical and biochemical attributes—such as pigmentation, flesh texture, aroma, and nutrient components
Bo Zhang, Xue-Ren Yin, Ji-Yuan Shen, Kun-Song Chen, and Ian B. Ferguson
Change in fruit volatile production is one of the main processes occurring during fruit ripening and senescence. Fatty acid-derived straight-chain aldehydes produced through the lipoxygenase (LOX) pathway are widely found in many fruit ( Baldwin
A. Erez, Z. Yablowitz, and R. Korcinski
Fresh fruits of stone fruit species are either lacking or in short supply in the months of March and April on the world market. This results from the absence of late-maturing cultivars in most of these species and from their poor storage capabilities. In March–April, supply from the Southern Hemisphere is dwindling or finished, while supply from the Northern Hemisphere has not started yet. A horticultural system was developed in Israel to get early fruit ripening of stonefruit species. The system developed is based on early completion of dormancy requirements followed by greenhouse tree growing. The system uses the following elements: 1) Improve chilling accumulation in winter by using evaporative cooling, to prevent chilling negation by high day temperatures. 2) Monitor salt accumulation level to prevent damage to branches and buds. 3) Monitor bud temperature and evaluate dormancy development according to the dynamic model. 4) Use dormancy breaking chemicals to compensate for part of the chilling not applied. 5) Cover of the trees with polyethylene having the appropriate characteristics of light filtering. 6) Keep the temperature in the greenhouse lower than the maximal temperature allowed, at every specific stage of development by ventilation. By using this system, fruit ripening was advanced by 4 to 6 weeks in peaches and nectarines (harvested from late March) and by 4 weeks in sweet cherries (harvested from April 11). Yields of 20 to 30 tons/ha were obtained in both species with high fruit quality.
Sogo Nishio, Masahiko Yamada, Yutaka Sawamura, Norio Takada, and Toshihiro Saito
; Segura et al., 2009 ; Zhang et al., 2010 ). Because important target traits such as fruit ripening time, fruit weight, and sugar content are quantitative, the fluctuation of phenotypic values with environmental conditions hinders the identification of
Jianguo Li, Hong Zhu, and Rongcai Yuan
; Taylor and Whitelaw, 2001 ). Abscission occurs at predetermined sites referred to as abscission zones in response to developmental cues such as those occurring during fruit ripening or stresses, including drought, temperature extremes, wounding, chemical
John C. Beaulieu and Mikal E. Saltveit Jr.
The content of acetaldehyde (AA) and ethanol (EtOH) increases in ripening climacteric fruit. Application of EtOH inhibits tomato (Lycopersicon esculentum) fruit ripening without affecting subsequent quality, and AA enhances organoleptic quality. AA inhibited ripening of mature-green tomato discs (MGTD) at about 30% conc of EtOH. The relationship between EtOH and AA inhibition of tomato fruit ripening is unclear. The inter-conversion of AA and EtOH is catalyzed by alcohol dehydrogenase (ADH) which is inhibited by 4-methylpyrazole (4-MP). No adverse physiological effects upon ripening were observed in MGTD receiving 20 μL of 4.0 mM 4-MP. Treating MGTD with 0.5 to 4.0 mM 4-MP in concert with AA (≤2.0 μL/g FW) or EtOH (≤8 μL/g FW) was not deleterious to ripening. A rapid, efficient method for the analysis of tissue AA and EtOH was linear (r2 = 0.97) for discs spiked with 0 to 45 μL EtOH. No temporal (0 to 42 h) changes in tissue AA and EtOH were detected in MGTD receiving 2.0 mM 4-MP. MGTD treated with 2.0 mM 4-MP and 8 μL/g FW EtOH had a 360-fold increase in AA after 6 days of ripening, but had no differences on EtOH conc. These conditions maximally inhibited ripening as determined by lycopene content.