Dark browning of fruit skin of Japanese pear `Niitaka' (Pyrus pyriforia) is a physiological disorder during storage. Very higher rates of dark browning were observed in bagged pears, and in the orchards under higher humidity during the maturing season. Also the factors, such as higher humidity and lower temperature in storage room increase the dark browning. Dark browning is a different physiological disorder with the sugerficial scold of apples, which associated with conjugated trienes, oxidation products of alpha-farnesenes. The dark browning was controlled by dipping the harvested pears into 1,000 ppm diphenylamine (DPA) solution for 5 seconds before storage.
Wol Soo Kim, Seong Bong Kim, Nam Hyun Song, and Han Chan Lee
Fernando Montero de Espinosa Baselga, Jonathan R. Schultheis, Michael D. Boyette, Lina M. Quesada-Ocampo, Keith D. Starke, and David W. Monks
physiological disorder that occurred in certain clones. An ethephon compound (PREP; Bayer Crop Science, Research Triangle, NC) releases ethylene which is the active ingredient in several commercial products. Ethylene is commonly used as a defoliator in cotton
Joshua D. Klein and Susan Lurie
Commercial, ecological, and agrotechnical considerations have recently renewed interest in the use of physical rather than chemical means to maintain postharvest quality of horticultural crops. This review discusses prestorage heat treatments that protect against physiological disorders, enhance natural resistance to pathogen infection, reversibly inhibit fruit ripening, and permit flexibility in storage temperatures.
Moritz Knoche, Eckhard Grimm, Andreas Winkler, Merianne Alkio, and Jürgen Lorenz
Neck shrivel is a nonpathogenic, physiological disorder of european plum that occurs preharvest during late fruit development and that continues to develop postharvest. Symptomatic fruit is perceived to be poor quality so has reduced commercial
T. Casey Barickman, Dean A. Kopsell, and Carl E. Sams
Freitas et al., 2011 ), especially the distal tissue ( Barickman et al., 2014b ). Insufficient Ca uptake and movement in tomato fruit tissue can result in the physiological disorder BER, which is associated with a Ca deficiency in the distal fruit tissue
Robert Bevacqua, Eugene Mielke, Timothy Facteau, Ruth Lavon, and Paul Chen
An assay for pyruvate kinase (PK) was tested as a diagnostic tool for cork spot, a major physiological disorder in pear Pyrus communis L. cv. d'Anjou) fruit. PK activity and Ca and protein concentrations were measured in peel of normal and affected fruit during selected months in 2 years. Protein concentration was more closely associated with cork spot than PK activity or Ca concentration. These preliminary results suggested the PK assay was a poor diagnostic tool for cork spot.
Yasseen Mohamed-Yasseen and Walter E. Splittstoesser
A micropropagation procedure was developed to regenerate plants via tissue culture from explants of harvested and stored French endive (Cichorium intybus L. Witloof). The procedure permits the rescue of French endive germplasm that shows resistance to postharvest physiological disorders and diseases. The procedure was used successfully to regenerate plants which showed resistance to different undesirable marketable traits.. Under a long day photoperiod, a high percentage of the explants produced flowers in vitro. Thidiozuron was used successfully to regenerate plants from small leaf explants.
Y. Suenaga, K. Takamori, F. Nishimot, S. Miyoshi, and T. Higashi
It is not uncommon that tipburns, deformation, and poor coloring of strawberries, delaying of differentiation of flowering buds and flowering, etc., occur reflecting rapid changes in soil solution concentrations by repeated applications of conventional fertilizers. These physiological disorders contribute to lowering the yield and quality of strawberries to a significant extent. Polyolefin coated urea called “MEISTER” is one of the excellent controlled availability fertilizers whose dissolution is primarily controlled by temperature. Therefore, blended materials of a few MEISTER products can supply N matching the plant demand for the long growing season (8 months). This results in contributing to the prevention of occurrences of the physiological disorders described above. Treatment plots using blended materials of MEISTER products were early dissolution, even dissolution, and late dissolution and were fertilized with a single basal application. Compared with the conventional plot, the late dissolution plot was most suitable for strawberry growth, producing the largest yield of high quality. The new fertilization using MEISTER will contribute to decreasing the amount of fertilizer to apply, eliminating topdressing, saving labor cost, etc.
Yong-Soo Hwang, Jong-Pil Chun, and Jae-Chang Lee
Physiological disorder occurred in a recently developed oriental melon cultivar, `Gumssaragi-Bunchun' (Cucumis melo var. makuwa), is involved with the appearance of water soaking area in placenta and can be extended to the pulp when severely affected. Physiological changes between normal and disordered fruits were compared. Ethanol soluble sugars were significantly decreased in both pulp and placenta tissue of disordered fruits whereas acidity was increased. Ethanol and acetaldehyde accumulation were confirmed in juice from disordered fruits, which were net detectable in normal ones. The contents of boron and calcium, especially water and HCl soluble calcium, were fairly low in disordered pulp. Also, there was a great difference in pectin content between both fruit tissue and severe hydrolysis of water soluble pectins isolated from disordered placenta was found by gel chromatography. However, the hydrolysis of pectins seemed not to be associated with the increase of wall hydrolase activities such as polygalacturonase and β-galactosidase.
Robert P. Sabba and Bill B. Dean
Potato tubers (Solanum tuberosum) of genotypes that vary in resistance to dark pigment formation when damaged, characteristic of the physiological disorder blackspot, were assayed for free tyrosine. The tubers were also assayed for relative levels of chorismate mutase and proteinase activities, which can regulate free tyrosine levels. The susceptibility of potato tubers to blackspot was shown to be correlated to the amount of free tyrosine by third order regression (R = 0.88). Tyrosine was found to be a limiting factor in pigment development. Chorismate mutase activity (CMI and CMII) was not correlated to blackspot susceptibility of the genotypes studied. Proteinase activities of Atlantic, TXA 763-5, Ranger Russet, Russet Burbank, and Lemhi Russet tuber protein extracts measured with synthetic substrates correlated with blackspot susceptibility. This suggests that the high free tyrosine levels associated with blackspot susceptibility may be due to high levels of proteinase activity in the tuber, rather than tyrosine synthesis.