`Bing' and `Rainier' sweet cherry (Prunus avium L.) fruit treated with 1-methylcyclopropene (1-MCP) were stored at 20 °C in air or 35 μL·L-1 ethylene. Ethylene production by both `Bing' and `Rainier' fruit stored in air was transiently stimulated following 1-MCP treatments, however, there were no significant effects of 1-MCP on respiration rate. Exogenous ethylene stimulated respiration regardless of prior treatment with 1-MCP. Although 1-MCP treatment reduced the increase in `Bing' respiration induced by ethylene, the reduction was less than reported previously for climacteric fruit. These results suggest that stimulation of sweet cherry fruit respiration by ethylene occurs via a process that may be independent of receptors to which 1-MCP binds. Postharvest changes in fruit color and development of stem browning were not altered by 1-MCP treatment, and exogenous ethylene accelerated the development of stem browning regardless of prior treatment with 1-MCP.
Yiping Gong, Xuetong Fan, and James P. Mattheis
F. Kappel, P. Toivonen, D.-L. McKenzie, and S. Stan
Several sweet cherry (Prunus avium L.) cultivars were stored in air or modified-atmosphere packages (MAP) at 1 °C for 2 or 4 weeks, respectively. The new cultivars included `Santina', `Sumpaca Celeste', `Sumnue Cristalina', `Sumste Samba', `Sandra Rose', `Sumleta Sonata', and `Skeena', and the standards were `Lapins', `Sweetheart', and `Bing'. Fruit were rated for defects (stem browning, stem shrivel and fruit surface pitting), and fruit quality at harvest and after storage. Weight loss during storage was influenced by year, storage treatment, and cultivar. Stem shrivel, stem browning, and fruit surface pitting varied among cultivars and years. Generally, fruit stored in MAP had higher fruit firmness than at harvest or when stored in air. The respiration rate of fruit was lower in later than in earlier maturing cultivars, but respiration rate at harvest was not related to any of the quality measurements taken after storage.
Margaret A. Cliff, Kareen Stanich, and Peter M.A. Toivonen
supplement as colorless and odorless ( Cultiva, 2015 ), no objective information is available on its impact on flavor, textural attributes (crispness, firmness, and juiciness), and visual characteristics (stem browning, pitting, and pebbling), particularly
Peter M.A. Toivonen
quality defects (pitting, decay and stem browning) was assessed using previously described hedonic scales ( Kappel et al., 2002 ; Toivonen et al., 2004 ). Firmness was measured before and after storage using a FirmTech I testing instrument (BioWorks
Todd C. Einhorn, Yan Wang, and Janet Turner
10 or 30 ppm were significantly firmer and had numerically less stem browning (SB) at the end of cold storage than untreated fruit; the effects were rate-dependent ( Horvitz et al., 2003 ). GA lengthened the storability of ‘Bing’ ( Zhang and Whiting
Carlos H. Crisosto, David Garner, Gayle M. Crisosto, Steve Southwick, and Mark A. Ritenour
During the past 5 years, we have investigated the relationship between cherry skin color stages (light red, 50% bright red, 100% bright, and dark red) measured at harvest and harvest/shipping quality for `Brooks', `Tulare', and `King' cultivars. This relationship was studied with fruit grown in different geographic locations within the San Joaquin Valley (SJV). SSC increased, but titratable acidity levels did not change as cherries matured to the dark skin color. The perception of sweetness, sourness, and cherry flavor by a trained taste panel was related to the different cherry skin color stages. Dark red color developed on cherries picked at earlier color stages after simulated shipment. Pitting and stem browning were the main market life limitations. Pitting, stem browning, and decay were higher on cherries picked at the dark and 100% bright red colors than cherries picked at earlier stages.
Mingqi Wang and Lixin Peng
Physiological, biochemical and anatomical indexes were investigated for rose hardiness. It was found that bound/free water ratio, proline accumulation, photosynthetic rate, palisade/spongy tissue ratio, and lignification of winter-acclimated stems were heavily influenced by the temperature causing stem browning. Spongy cell volume and stem tenderness were inversely related to winter hardiness. Data generated from this research demonstrated that catalase stability, TTC reduction rate at 0°C, total photosynthetic rate, stem pith ray number, and leaf wax thickness are good indicators for rose hardiness to freezing temperatures. Two compound indexes were developed through the main component analysis. Based on the results obtained from 12 tested cultivars, these indexes are ideal to quantify hardiness of rose germplasm.
Rong Tsao and Ting Zhou
The banning of synthetic fungicides for postharvest use on fruits in Canada has prompted a search for alternative control strategies for postharvest brown rot caused by Monilinia fructicola (Wint.) Honey on sweet cherry (Prunus avium L.). Thymol and carvacrol were the two most potent fungicides among the monoterpenoids tested. The brown rot incidences of M. fructicola-inoculated cherry dipped in 1000 μg·mL-1 thymol and carvacrol were 24% and 23%, respectively, compared with 81% for the control. The effects of thymol and carvacrol were not significantly enhanced by the addition of CaCl2 or CaB'y®, a foliar calcium fertilizer. Decco® 282 significantly reduced the activity of thymol. Methyl jasmonate, an elicitor of plant defense mechanisms, did not reduce brown rot by itself, and did not increase the efficacy of thymol and carvacrol when used as an additive in dipping or fumigation experiments. Thymol and carvacrol caused stem browning of cherry fruits in the fumigation experiment, however, 69% and 73%, respectively, of the browning was prevented when methyl jasmonate was used as a co-fumigant. Chemical names used: 5-methyl-2-(1-methylethyl)phenol (thymol); 2-methyl-5-(1-methylethyl)phenol (carvacrol); methyl 3-oxo-2-(2-pentenyl)cyclopentane acetate (methyl jasmonate).
Johan Desaeger and Alex Csinos
The effects of drip-applied 1,3-dichloropropene (1,3-D) and chloropicrin on fumigant soil gas levels and growth of vegetable seedlings were investigated in three separate tests in Tifton, Ga. Tests were conducted in Spring 2002, Fall 2002, and Spring 2003. Phytotoxicity of 1,3-D + chloropicrin was induced in the 2002 tests by applying progressively higher rates (0 to 374 L·ha–1) of drip-irrigated InLine (an emulsifiable formulation (EC) containing 60.8% 1,3-D and 33.3% chloropicrin) and planting vegetable seedlings within four days after application. Vegetables evaluated were tomato, pepper and cucumber (Spring 2002), and tomato and squash (Fall 2002). In Spring 2003, the effects of 1,3-D formulation (InLine versus Telone EC, an EC containing 94% 1,3-D), plastic mulch type [low density polyethylene (LDPE) versus virtually impermeable film (VIF)] and drip tape configuration (one versus two drip tapes) on fumigant soil gas levels and growth of tomato were investigated. Tomato was planted after the recommended 3-week waiting period. Fumigant concentrations in soil were measured using Gastec detection tubes at 1 to 4 days after drip fumigation in all three tests. Measured fumigant soil gas concentrations were correlated with fumigant application rates in Spring 2002, but not in Fall 2002. Vegetables were visibly affected by residual fumigant levels in the soil and showed symptoms such as leaf chlorosis (cucumber, squash and pepper), leaf bronzing (tomato) and stem browning and stunting (all crops). Fumigant soil air levels were negatively and linearly correlated with different plant growth parameters, in particular plant vigor. The cucurbit crops showed an immediate response and high mortality within 1 week after planting. Surviving plants recovered well in fall. The solanaceous crops showed a more delayed response and lower mortality rates. However, phytotoxic effects with tomato and pepper were more persistent and plants did not seem to recover with time. Overall, fumigant residue levels and potential phytotoxicity were greater in spring than in fall. Greater fumigant soil concentrations were measured under VIF as compared to LDPE plastic mulch. The effect of drip-tape configuration varied with the type of plastic mulch that was used. The double-tape treatment resulted in lower fumigant levels at the bed center under LDPE mulch, and higher fumigant levels at the bed shoulder under VIF mulch. The formulation containing 94% 1,3-D resulted in higher soil fumigant levels as compared to the formulation containing 61% 1,3-D and 33% chloropicrin, especially with VIF mulch. Early plant vigor of tomato was negatively correlated with fumigant soil gas levels, and was especially poor following drip fumigation with 94% 1,3-D under VIF mulch.
Jonathan Tong, Cyril Rakovski, and Anuradha Prakash
, where the entire rachis including the cap stems were green. A score of 2 was given to a rachis with only cap stem browning. A score of 3 was given to a rachis with moderate browning, where the cap stems and secondary rachis displayed browning. Finally, a