The Role of Net Development as a Barrier to Moisture Loss in Netted Melon Fruit (Cucumis melo L.)

Abstract

<jats:p>The transpiration rate of cuticular membrane and fissures that comprise the netting on fruits of three netted melon cultivars, Life, Andesu, and Gurandoru, were measured during fruit development. Fissures in the equatorial region first developed vertically, then became interconnected by horizontal fissures as the fruit developed. Some cracks remained along the net, even at the fruit ripening stage, regardless of cultivar. Both lignified and suberized cell wall layers in the net tissues of the cultivar Life were thinner than those of the other cultivars, probably because of the shorter developmental period of fruits in the variety. Nevertheless, net transpiration rate did not differ significantly among cultivars at the fruit ripening stage. Peroxidase (POD) activity in the skin tissues of ‘Life’ was lower than that in ‘Andesu’ and ‘Gurandoru’ throughout fruit development and was not correlated with climacteric ethylene production. Among these cultivars, significantly higher ethylene production occurred in ‘Life’ fruit at the ripening stage. This can accelerate membrane permeability of hypodermal tissues, resulting in rapid fruit softening. Our results indicate that the net tissues of netted melons can be as waterproof as cutinized membranes if suberized cell wall layers with wax depositions develop below the net fissures at the fruit ripening stage.</jats:p>

Mapping quantitative trait loci for fruit traits and powdery mildew resistance in melon (Cucumis melo)

“…However, the differences in the mapping results between the two trials depict significant genotype-by-trial interactions for ND and NW confirmed by the combined analysis of variance mentioned earlier. This suggests ND and NW are at least partly affected by environmental factors similar results were reported in previous studies (Keren-Keiserman et al 2004 ; Puthmee et al 2013 ). Two QTLs (i.e., qNW2 and qNW7 ) were identified in both trials, indicating relatively stable ones which would be useful for MAS in the future.…”

“…Mapping of QTLs for netting width of fruit rind was unique in this study. Netting on melon surface, a wound-healing network pattern, has been reported results from a series of histological and biochemical processes (Keren-Keiserman et al 2004 ; Puthmee et al 2013 ). Fruit netting was scored by both netting density and netting width in which the same QTLs in LG 2, 4, 6, and 7 were identified for both traits.…”

The metabolic and proteomic repertoires of periderm tissue in skin of the reticulated Sikkim cucumber fruit

“…The formation of lignosuberized periderm tissue holds agronomical and physiological significance as it maintains the integrity of the skin surface, and protects the growing and expanding fruit under skin-failure circumstances [ 4 ]. Previous studies established that reticulation impacts melon fruit skin firmness and elasticity [ 5 , 6 , 7 ], maintains the turgor pressure and waterproofing volume of hypodermal cells lying beneath the skin layer [ 8 ], and delivers enhanced tolerance against mechanical injury [ 9 ]. Similarly, newly-formed phellem cells that build the russeted coating in apple fruit were shown to replace damaged epidermis cells, thereby preserving normal water loss during fruit development and post-harvest [ 2 , 10 ].…”

A Multilevel Study of Melon Fruit Reticulation Provides Insight into Skin Ligno-Suberization Hallmarks

“…Furthermore, peroxidase activity was associated with processes of suberization and lignification occurring at the reticulated surface (Keren-Keiserman et al, 2004b). Differences in the structure of the skin surface, smooth or reticulated, impact fruit physiology and development, including firmness and elasticity (Rose et al, 1998;Dos-Santos et al, 2011;Puthmee et al, 2013), waterproofing capacity, and turgor pressure of hypodermal tissues (Saladié et al, 2007). They further confer tolerance against mechanical damage (Keren-Keiserman et al, 2004a).…”