Ethylene Production and Respiratory Behavior of the rin Tomato Mutant

Abstract

Little or no change in ethylene or C02 production occurred in rin tomato mutant fruits monitored for up to 120 days after harvest. Of the abnormally ripening tomatoes investigated, including "Never ripe" (Nr Y a h, Nr c 12 r), "Evergreen" (gf r) and "Green Flesh" (gf), only rin did not show a typical climacteric and ethylene rise.Fruits from F1 plants resulting from reciprocal crosses between rin and normal plants apeared to ripen normally, but when compared to normal fruit, their ripening was delayed as measured by ethylene and C02 production and color change. These fruits produced only one-third to one-half as much ethylene at the peak of production compared to normal fruits.Exogenous ethylene or propylene treatment did not stimulate ethylene production by rin fruits but did stimulate C02 production. The C02 stimulation persisted only in the presence of the exogenous olefins. Stimulation of C02 production could be repeated several times in the same fruit. Wounding stress stimulated both ethylene and C02 production in rin fruits. It was concluded that rin tomato fruits behave like nonclimacteric fruits.catalytically (6,19). Propylene treatment of these fruits stimulates both ethylene production and respiration (19).In climacteric fruits, ethylene is generally considered to be the trigger of the ripening syndrome (21), and its presence at proper levels has been shown to be necessary for normal ripening (7, 16).Normal tomato fruits have been shown to be of the climacteric type (2,8,10, 27,28), and the response of tomato fruits to ethylene treatment has been investigated (15, 22). As in other tissues (1,17,18,26), tomato fruits respond to wounding stress by greatly increased ethylene and CO2 production (20).Reports concerning abnormally ripening tomato mutants have been published (13,14,24). Of special interest is the rin tomato mutant described by Robinson and Tomes (25) as a spontaneous mutation in a breeding line. Fruits of the rin mutant remain green while normal fruits ripen and turn red. The mutant eventually turns a lemon color with little or no lycopene development. Genetic analysis showed that rin was a monogenic recessive determined characteristic with no linkage associations except large sepal size. Little work has been done on the physiology or biochemistry of these ripening mutants (11). The respiratory and ethylene production behavior of the rin tomato mutant is described in this report. MATERIALS AND METHODSBiale (4) 6242.Plants of the F5 generation of rin and the normal breeding line (61-37, Fireball X Cornell 54-149) from which it originated were grown in the greenhouse (15 C night, 20 C day) and trained to a single stem. Flowers were tagged at anthesis with only one flower (lst or 2nd) per cluster being pollinated. All others in a cluster were excised. Fruit load per plant was limited to 8 to 10 fruits. Fruits were harvested 30 days after anthesis, the stems were removed carefully, and fruits were washed in water and dried with paper towels. Fruits of similar size were used for all tr...

Acetaldehyde Stimulation of Net Gluconeogenic Carbon Movement from Applied Malic Acid in Tomato Fruit Pericarp Tissue

“…The increase was particularly obvious in the ripe Rutgers tomato, presumably due to the fruit tissue predisposition to sugar synthesis as shown above. The response of the rin, behaving like nonclimacteric fruit (8), is also significant; although in this tissue, the magnitude of the 14C recovery in the sugar fraction is equivalent to that of the green Rutgers fruit, the AA-treated rin mimicked a metabolic activity found in climacteric fruit. In ripening banana, starch is degraded to triose or hexose phosphates which diffuse from the amyloplast to the cytosol and are metabolically apportioned for glycolysis and in addition for gluconeogenesis (1).…”

Ripening-Regulated Susceptibility of Tomato Fruit toBotrytis cinereaRequiresNORBut NotRINor Ethylene

“…Nonripening Nr mutant fruit and unripe wild-type fruit treated with sufficient 1-MCP to stop normal ripening remain partially resistant to B. cinerea. Although they perceive ethylene, rin and nor mutant fruit fail to ripen (Herner and Sink, 1973;Tigchelaar et al, 1973;McGlasson et al, 1975a;Giovannoni, 2007b). Ethylene treatment of rin fruit induces the expression of some ripening-regulated genes (Lincoln and Fischer, 1988), and wounding rin and nor fruit induces ethylene production (Yokotani et al, 2004).…”

“…No significant increase in ethylene evolution from MG and RR wild-type fruit inoculated with B. cinerea was observed at 1 dpi (Table I), although significant accumulation was observed at 3 dpi. Uninoculated rin and nor fruit produced less ethylene at all ripening stages compared with uninoculated wild-type fruit (Table I; Herner and Sink, 1973;McGlasson et al, 1975aMcGlasson et al, , 1975bThompson et al, 1999).…”

Ethylene Production and Respiration in Aging Leaf Segments and in Disks of Fruit Tissue of Normal and Mutant Tomatoes

“…We have now shown that there is an active conversion of methionine to ethylene in wounded fruit tissue of both rin and nor, quantitatively similar to that in wounded normal fruit tissue. The production of ethylene in response to wounding contrasts with the lack of a natural respiratory climacteric and parallel increase in ethylene production during aging in whole rin fruit (3,5), and the occurrence of only a very small rise in ethylene production but no respiratory climacteric in intact aging whole nor fruit (2). These apparent differences in ethylene metabolism in aging leaves and freshly cut disks compared with intact aging whole fruits support Zobel's (11) suggestion of a possible divergence of mechanisms controlling ethylene synthesis in different tissues.…”

“…Physiological studies with rin have shown that developing fruits contain low levels of ethylene similar to those in a normal strain and eventually turn yellow on the plant or following detachment (3,5 in this laboratory (2) has shown that immature fruits of nor also fail to exhibit a respiratory climacteric. Yellowing in nor fruits is associated with a small rise in ethylene production to a peak value about one-eighth of that in normal fruit.…”