Texture is an important quality trait for fruit ( Li et al., 2010 ). Postharvest softening usually occurs in most fruit, but lignification is an uncommon phenomenon occurring in ripening fruit, which is usually accompanied by increased fruit
Xue Li, Chen Zang, Hang Ge, Jing Zhang, Donald Grierson, Xue-ren Yin, and Kun-song Chen
William M. Walter Jr., Betsy Randall-Schadel, and William E. Schadel
Wound healing in cucumber fruit (Cucumis sativus L., cv. Calypso) was studied using histological and degradative techniques. A thick exudate appeared at the wounded surface shortly after wounding. This material retarded water loss and possibly aided in the formation of sclerified parenchyma observed 24 hours after wounding. The sclerified material was positive to a modified Weisner stain, indicating lignification was occurring. Wound periderm (cork) was initiated directly beneath the sclerified parenchyma cells within 48 hours after wounding. The cork layers were positive to Sudan IV stain, indicating suberin was being formed. The rate of phellem development decreased by 6 days after wounding. By day 7, younger phellem cells and sclerified parenchyma cells were stained by Sudan IV. Degradation of the wound tissue by chemical procedures demonstrated that relatively large amounts of lignin and suberin were deposited during healing. Fragments from the lignin degradation Indicated that lignin was composed mainly of gualacyl and p-hydroxyphenyl residues. Suberin was found to contain mainly 1,16-hexadecane and 1,18-osctadecene decarboxylic acids detected as the silylated diol derivatives.
Zhiyong Hu, Qing Liu, Meilian Tan, Hualin Yi, and Xiuxin Deng
. 2H ). Light microscopy of cross-sections of juice sacs revealed lignification in the cell walls of the “brown thorns” ( Fig. 2I ). Moreover, the cell walls near the “brown thorns” also thickened obviously ( Fig. 2J ), which was different from that of
Shutian Tao, Danyang Wang, Cong Jin, Wei Sun, Xing Liu, Shaoling Zhang, Fuyong Gao, and Shahrokh Khanizadeh
leads to tissue lignification, which can influence fruit texture and postharvest handling ( Cai et al., 2006 ). The present study found a strong correlation between the formation of stone cells and lignin biosynthesis, a finding that supports the view
Ed Etxeberria, William M. Miller, and Diann Achor
Fruit etching is an alterative means to label produce. Laser beam-generated pinhole depressions form dot-matrix alphanumerical characters that etch in the required price-look-up information. Pinhole depressions can disrupt the cuticular and epidermal barriers, potentially weakening the natural protection against pathogens. In the present study we describe the anatomical and morphological characteristics of the pinhole depressions in the cuticle/epidermis, and the changes taking place during storage of two fruits: avocado (Persea americana) and tomato (Lycopersicon esculentum). These fruits represent the extremes from a thick, non-edible peel to a thin edible peel. On both tomato and avocado, etching depressions were fairly similar in diameter and depth, averaging 200 μm and 25 μm, respectively, for energy impact durations of 30 μs for tomato and 45 μs for avocado. Immediately after etching, the two- to five-cell-deep depressions contained cuticle/wax deposits. Additional cuticle/wax material was deposited in and around the depressions during storage as demonstrated by confocal, fl uorescent, and light microscopy. In addition, the cells underlining the etch depression increased phenolic and lignin deposits in their walls, creating a potential barrier against pathogenic organisms.
Ann M. Callahan, Chris Dardick, and Ralph Scorza
. These studies and others have shown an increase in stone dry weight and lignification that begins in the second stage of fruit development until maturity ( Nakano and Nakamura, 2002 ; Ryugo, 1961 ). Studies in peach directed toward increasing fruit size
Xiang Wang, Ramón A. Arancibia, Jeffrey L. Main, Mark W. Shankle, and Don R. LaBonte
and Lulai, 2002 ; Webster et al., 1973 ). The wound healing process is characterized by suberization/lignification of the exposed cells and developing of the new periderm beneath ( Lulai and Suttle, 2004 ; St. Amand and Randle, 1989 ). In addition
Arthur Q. Villordon, Don R. La Bonte, Nurit Firon, Yanir Kfir, Etan Pressman, and Amnon Schwartz
cut ends, i.e., “wound” roots ( Belehu et al., 2004 ; Togari, 1950 ). These roots became fibrous roots and exhibited regular secondary growth and lignification of the stele, or storage roots, and exhibited proliferation of cambial cells that formed
Ann Callahan, Chris Dardick, Roberta Tosetti, Donna Lalli, and Ralph Scorza
measured in peach to look at gene expression associated with endocarp formation. From these studies it was found that there were specific genes involved with lignification that were expressed in endocarp and then only at specific times in development
Marie-Therese Charles, Alain Goulet, Francois Castaigne, and Joseph Arul
Hormic dose of ultraviolet light (3.7 kJ•m-2) induced disease resistance in tomato fruit. The biochemical nature of induced resistance by UV light was investigated by histochemical techniques. Ultraviolet light induced plasmolysis of the epicarp and few mesocarp cell layers, and collapse of these cell layers led to the formation of cell wall stacking zone (CWSZ). The treatment also stimulated the biosynthesis of phenolic compounds (Prussian blue reaction) in the epicarp and mesocarp cells. Biochemical reinforcement of the cell wall through lignification (Maule test) and suberization (berberine fluorescence) was also induced. These responses originating from the activation of phenylpropanoid path were principally localized in the CWSZ and were induced before inoculation by B. cinerea. The intensity of these responses was significantly increased in UV-treated tissue in response to infection. These responses were also induced in the inoculated control tissue but were either less substantial (phenolics, lignification, and suberization) or delayed.