逐步降温对哈密瓜果实采后冷害、品质及内源激素的影响

Effects of gradual cooling treatment on chilling injury,quality and endogenous hormones of Hami melon(Cucumis melo L.)fruits

【目的】探讨逐步降温处理对‘86-1’哈密瓜果实采后冷害、品质及内源激素含量的影响,为新疆哈密瓜采后低温贮运保鲜提供参考。【方法】以‘86-1’哈密瓜果实为研究对象,研究直接降温（（1±0.5）℃,对照）和逐步降温（（8±0.5）℃,1d→（5±0.5）℃,3d→（3±0.5）℃,3d→（1±0.5）℃）处理对其采后贮藏过程中的冷害指数、冷害率以及果实硬度、可溶性固形物、可滴定酸、维生素C、脱落酸（ABA）、吲哚乙酸（IAA）、赤霉素（GA）、玉米素（ZR）含量的影响。【结果】逐步降温处理可使‘86-1’哈密瓜果实的冷害发生时间推迟42d,贮藏63d后冷害率仅为对照的10.53%。逐步降温处理显著抑制‘86-1’哈密瓜果实的硬度和维生素C含量的下降,贮藏49d时,逐步降温、对照处理的果实硬度分别下降了39.37%和45.48%,贮藏63d时,以上两组处理的果实维生素C含量分别下降了56.17%和73.42%;但逐步降温、对照处理对可溶性固形物和可滴定酸含量的影响不明显,贮藏63d后,逐步降温、对照处理的果实可溶性固形物含量分别下降至8.52%和8.07%,下降幅度分别为31.57%和35.18%;两组处理的果实在整个贮藏期内可滴定酸含量基本维持在0.085%~0.112%;贮藏14~63d,与对照相比,逐步降温处理的果实中ABA、IAA、GA及ZR含量维持在较高水平。【结论】逐步降温处理（（8±0.5）℃,1d→（5±0.5）℃,3d→（3±0.5）℃,3d→（1±0.5）℃）能有效延缓及控制‘86-1’哈密瓜果实采后冷害的发生,提高果实内源激素的水平,较好地保持果实品质。

【Objective】This study investigated effects of gradual cooling treatment on chilling injury,quality and endogenous hormones of‘86-1＇Hami melon（Cucumis melo L.）fruits to improve storage and transportation under low-temperature after harvest.【Method】Fruits of‘86-1＇Hami melon were tested with direct cooling（（1±0.5）℃,control）and gradual cooling treatments（（8±0.5）℃,1d→（5±0.5）℃,3d→（3±0.5）℃,and 3d→（1±0.5）℃）to investigate the changes of chilling injury index,chilling injury incidence,firmness,and contents of soluble solid,titratable acidity,vitamin C,endogenous abscisic acid（ABA）,gibberellin（GA）,indole acetic acid（IAA）,and Zeatin（ZR）of‘86-1＇Hami melon（C.meloL.）fruits.【Result】Gradual cooling treatment could delay the chilling injury 42 days later than the control,and the chiliiing injury incidence was 10.53% of control after 63days;Gradual cooling treatment markedly inhibited the decline of fimness and vitamine C content,the fimness of gradual cooling treatment and the control delined 39.37% and 45.48% at 49 days,and vitamine C content of them delined 56.17%and 73.42% at 63 days,respectively.But there was no effects on soluble solid content and titratable acidity,the two treatments decreased 8.52% and 8.07%,the degree of declining was 31.57% and 35.18% after 63 days,respectively.The titratable acidity of them remained at 0.085%-0.112% during storage.Compared with control,gradual cooling treatment maintained higher level of abscisic acid（ABA）,indole acetic acid（IAA）,gibberellin（GA）and Zeatin（ZR）of‘86-1＇Hami melon（C.melo L.）fruits from 14 days to 63 days.【Conclusion】Gradual cooling treatments（（8±0.5）℃,1d→（5±0.5）℃,3d→（3±0.5）℃,and 3d→（1±0.5）℃）effectively delayed and controlled the incidence of chilling injury,improved endogenous hormones,and maintained high fruit quality of‘86-1＇Hami melon（C.melo L.）fruits.