No Delay Its Mechanism Of Action Of Garlic Aging

NO as a new type of intercellular and intracellar signaling molecule messaging become a research hotspot. NO has been found the role of delaying in a variety of fruits and vegetables senescence. Redistribution of cell in excised garlic scape lead to decline in eating quality, of such models of the aging mechanism of fruits and vegetables is unknown. In this study, garlic scape as the typical models of transport of substances, study the effects of NO on the role of senescence mechanisms transduction in excised garlic scape, in order to provide scientific basis to solve this kind of horticultural products of storing and keeping fresh problems.Using sodium nitro prusside (SNP) as a nitric oxide (NO) donor, Hemoglobin (HB) as a NO scavenger, N^ω-nitro-L-arsinine methylter (L-NAME) as a NOS inhibitor, Sodium Tungstate as a NR inhibitor, Diphenyl iodine (DPI) as a NADPH oxidase inhibitor, Ascorbic acid (ASA) as a H₂O₂ scavenger, Physiological and biochemical methods combined with confocal laser scanning microscopy technology, Preliminary exploration of mechanisms of NO on transport of substances in excised garlic scape. The results as follows:1. The results showed that suitable concentration of SNP had a remarkable effect on garlic scape preservation. It can inhibited the diameter of garlic bulbet and the degree of fibrosis increased, delayed the content of soluble suger and soluble protein in the basal of garlic scape, and the garlic scape were keeped viridity. 0.1 mmol·L^-1 SNP solutions three hours at the basal of garlic scape was the best effect concentration in Preservation. But overhigh concentration of SNP (0.5mmol·L^-1) will cause the garlic sacape tissues injuries.2. SNP treatment could significantly inhibit the increased of the diameter of garlic bulbet and the content of H₂O₂. 0.1 mmol·L^-1 SNP inhibited the increased of the diameter of garlic bulbet and the content of H₂O₂ in basal garlic scape, relative membrane permeability increased, activities of peroxidase (POD) in basal garlic scape increased and promoted the activity of catalysis of superoxide dismutase (SOD), catalysis of catslase (CAT), ascorbate peroxidase (APX) in garlic scape and POD in apical garlic scape during four centigrade degree cold storage.3. The acid phosphatase activities in the clove and the basal scape were very high, especially in the earier period of the pre-storage. However, with the time of torage, the acid phosphatase activities were a downward trend; Exogenous NO obviously slowed down the peak of acid phosphatase activities duing storage.4. Distribution of endogenous NO related to the speed and extent of redistribution of cell content. Endogenous NO distributed evenly in low degree of transport of tissues, with the degree of transport increasing, endogenous NO would gradually transfer from peripheral vascular metastasis to the central vascular and with the growth of cloves of garlic scape, not much change in distribution and the level of NO. Exogenous NO may induce endogenous NO level increased, which maybe through the ways of nitric oxide synthase.5. H₂O₂ Participate in postharvest nutrient re-distribution of garlic scape. Endogenous H₂O₂ has distributed in entire tissue of garlic scape throughout the transfer process, but in the aging tissues the congruent of H₂O₂ was no or very low. The H₂O₂ was very hige in eugenic apical tissue; High concentrations of H₂O₂ promoted redistribution of cell content and reduced the content of H₂O₂ in the basal garlic scape tissues could inhibit this action.6. Inhibition effect of endogenous NO on postharvest nutrient re-distribution of garlic scape maybe regulate to the endogenous H₂O₂ level in garlic scape.