Fresh fruits and vegetables have always made an important contribution to the human diet

Fruits can be divided into dry and fleshy types. Dry fruits mature through senescence and fleshy fruits through ripening. Previous studies have indicated that partially common molecular networks could govern fruit maturation in these different fruit types. However, the nature of such networks remains obscure. CLASS-II KNOX genes were shown to regulate the senescence of the Arabidopsis (Arabidopsis thaliana) dry fruits, the siliques, but their roles in fleshy-fruit development are unknown. Here, we investigated the roles of the tomato (Solanum lycopersicum) CLASS-II KNOX (TKN-II) genes in fleshy fruit ripening using knockout alleles of individual genes and an artificial microRNA line (35S:amiR-TKN-II) simultaneously targeting all genes. 35S:amiR-TKN-II plants, as well as a subset of tkn-II single and double mutants, have smaller fruits. Strikingly, the 35S:amiR-TKN-II and tknII3 tknII7/+ fruits showed early ripening of the locular domain while their pericarp ripening was stalled. Further examination of the ripening marker-gene RIPENING INHIBITOR (RIN) expression and 35S:amiR-TKN-II rin-1 mutant fruits suggested that TKN-II genes arrest RIN activity at the locular domain and promote it in the pericarp. These findings imply that CLASS-II KNOX genes redundantly coordinate maturation in both dry and fleshy fruits. In tomato, these genes also control spatial patterns of fruit ripening, utilizing differential regulation of RIN activity at different fruit domains.

Marketing melons (Cucumis melo) as convenient fresh-cut products is popular nowadays. However, damage inflicted by fresh-cut processing results in fast quality degradation and food safety risks. The life of fresh-cut produce can be extended by a modified atmosphere (MA), either generated in a package by tissue respiration (a passive MA) or injected by gas flushing (an active MA). This work investigated the effect of passive and active MA formed in packages of different perforation levels on the quality of fresh-cut melons of two genetic groups: C. melo var. cantalupensis, characterized by climacteric fruit behavior, and non-climacteric C. melo inodorus. The best product preservation was achieved in passive MA packages: non-perforated for inodorus melons and micro-perforated for cantalupensis ones. The optimal packages allowed for the preservation of both genotypes for 14 days at 6–8 °C. The major factors limiting the shelf life of fresh-cut melons were microbial spoilage, translucency disorder and hypoxic fermentation associated with cantalupensis melons with enhanced ethyl acetate accumulation. Inodorus melons were found to be preferable for fresh-cut processing since they were less prone to fermented off-flavor development.

There are gaps in our knowledge of the effects of irrigation water quality and amount on yield and postharvest quality of pepper fruit (Capsicum annuum L.). We studied the effects of water quality and quantity treatments on pepper fruits during subsequent simulated storage and shelf-life. Total yield decreased with increasing water salinity, but export-quality yield was not significantly different in fruits irrigated with water of either 1.6 or 2.8 dS/m, but there was a 30–35% reduction in export-quality yield following use of water at 4.5 dS/m. Water quantity hardly affected either total or export-quality yield. Water quality but not quantity significantly affected fruit weight loss after 14 days at 7 °C plus three days at 20 °C; irrigation with water at 2.8 dS/m gave the least weight loss. Fruits were significantly firmer after irrigation with good-quality water than with salty water. The saltier the water, the higher was the sugar content. Vitamin C content was not affected by water quality or quantity, but water quality significantly affected antioxidant (AOX) content. The highest AOX activity was found with commercial quality water, the lowest with salty water. Pepper yield benefited by irrigation with fresh water (1.6 dS/m) and was not affected by water quantity, but post-storage fruit quality was maintained better after use of moderately-saline water (2.8 dS/m). Thus, irrigation water with salinity not exceeding 2.8 dS/m will not impair postharvest quality, although the yield will be reduced at this salinity level.

For decades, heat treatments have been known to reduce or eliminate decay-causing agents and slow the physiological deterioration of freshly harvested fruits and vegetables. For years, fungicides and pesticides have been used to control fungi on freshly harvested fruits and vegetables. However, these chemicals can contaminate the environment and be hazardous to those who consume fresh produce. Therefore, heat treatments, lasting only minutes or up to several days, have been developed to control insects and pathogenic fungi on fresh produce after harvest. In the 1990s, hot water rinsing and brushing (HWRB) technology to clean and disinfect fresh produce at relatively high temperatures (50 to 62 °C) for seconds (12–20 s) was developed at the Volcani Institute in Israel. This technology has been improved over time and is currently used commercially on several crops in Israel and elsewhere. This article discusses the development of this prestorage technology, from 1996 to 2006, and describes the effects of HWRB on the internal and external characteristics of fruits and vegetables, as well as the possible mode of action of this technology, as examined in the literature published since 1996.