氧化亚氮(N_2O)熏蒸对木纳格葡萄贮藏品质的影响

Effects of N_2O Fumigation on Postharvest Quality of Munage Grapes

木纳格葡萄品质优良,但采后果实易出现失重软化、落粒以及果梗褐变等问题。为了探究小分子气体氧化亚氮(Nitrous oxide,N_2O)熏蒸对鲜食葡萄采后贮藏品质的影响。以新疆特色鲜食葡萄木纳格葡萄(Vitis vinifera L.cv.Munage)为试材,采用20、50和100μL/L的N_2O对木纳格葡萄进行间歇熏蒸处理(每7 d),在(0±0.5)℃的条件下贮藏70 d。测定了贮藏过程中木纳格葡萄的腐烂率、落粒率、失重率、硬度、可滴定酸、可溶性固形物、电导率、抗坏血酸过氧化物酶(Aseorbate peroxidase,APX)以及过氧化物酶(Peroxidase,POD)的变化。结果表明:50μL/L的N_2O熏蒸能保持可溶性固形物、可滴定酸的含量;有效抑制果实腐烂率、落粒率及相对电导率的上升,降低过氧化物酶和抗坏血酸过氧化物酶的活性,保持了较好的果实硬度,说明N_2O熏蒸能够延缓木纳格葡萄果实采后的衰老进程,较好的维持木纳格葡萄的采后品质。

Munage grapes were of good quality, but the postharvest grapes were prone to a series of problems such as weight loss, softening, grain dropping and fruit stem browning. In order to investigate the effects of nitrous oxide（N_2 O） fumigation on postharvest storage quality of Munage grapes,, Xinjiang（Vitis vinifera L.） cv Munage grapes were fumigated in different concentration of N_2 O（20, 50 and 100 μL/L） every 7 days, thereafter stored in the cold room（0 ± 0.5℃, 90~95% RH） for 70 d. The changes of decay rate, shattering rate, weight loss rate, hardness, titratable acid, soluble solids, conductivity, ascorbate peroxidase（APX） and peroxidase（POD）were measured during storage. The results showed that 50 μL/L of N_2 O fumigation could maintain the content of soluble solids and titratable acid and effectively inhibit the increase of decay rate, shattering rate and relative conductivity. In addition, N_2 O also decreased the activity of POD and APX, which significantly remained the hardness of grape. It demonstrated that N_2 O fumigation could delay senescence of the harvested fruit and could better maintain the postharvest quality of the Munage grapes.