Page 134 - 《广西植物》2020年第8期
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8 期 黄思婕等: 人工脱涩处理对广西野生柿种质果实贮藏性的影响 1 1 8 9
Abstract: In order to investigate the softening mechanism of putharvest fruits of Diospyros germplasmꎬ Diospyros oleiferaꎬ
cultivated persimmon and the main cultivar ‘Gongcheng persimmon’ in Guangxi were used as experimental materials to an ̄
alyze the changes of titratable acid contentꎬ soluble sugar contentꎬ firmnessꎬ ethylene biosynthesisꎬ total chromatismꎬ
soluble tannin contentꎬ pectin content and cell wall degrading enzyme activities in postharvest storage of artificially dehydra ̄
ted ethephon. The results were as follows: (1) Compared with ‘Gongcheng persimmon’ꎬ the Diospyros oleifera had high ti ̄
tratable acid contentꎬ low soluble sugar contentꎬ slow color change and easy softening of fruits. Among themꎬ YS ̄4 was the
most resistant to storage. After ethephon treatmentꎬ the firmness decreased to 1.620 N on the 4th dayꎬ and the soluble tannin
 ̄1
content decreased to 2.398 mgg on the 6th day. The pectin content decreased the most slowly during the whole storage
period. The soluble pectin content value was the lowest at the final phase (0.832%)ꎻ while YS ̄2 was the most resistant to
storageꎬ the firmness of ethephon treatment was 3.6 times than that of YS ̄4 on the 8th dayꎬ and the firmness at the end of
storage was the highest among all persimmon germplasms. (2) The titratable acid content of ZP ̄2 was the highestꎬ the solu ̄
ble sugar content was lowꎬ the change of color was the slowestꎬ the decline of original pectin was the leastꎬ and the content
of soluble pectin was the highest after the end of storage period of ethephon treatment. On the contraryꎬ ZP ̄3 fruit color
changed quickly and softened easilyꎬ the titratable acid content was the lowestꎬ the soluble sugar content was lowꎬ the origi ̄
nal pectin content was the biggestꎬ and the soluble pectin content was low. (3) Polygalacturonase (PG) and cellulase (Cx)
of ‘Gongcheng persimmon’ were much higher than D. oleifera during the ripening period after fruit softening. The relation ̄
ship between the softening degree and the cell wall degradation enzyme activity was different among all the persimmon germ ̄
plasms. β ̄D ̄galactosidase (β ̄D ̄Gal) and cellulase (Cx) played an important role in the early stage of storageꎬ while poly
galacturonase (PG) played an important role in fruit softening at the early and late stage of storage. The results suggest that
different persimmon germplasms have different enzymes that play major roles in fruit softening progress. In generalꎬ com ̄
pared with ‘Gongcheng persimmon’ꎬ the storage tolerance of D. oleiferaꎬ in which YS ̄4 was extremely intolerant to storageꎬ
and ZP ̄2 was extremely tolerant to storage. These results may provide a basis for the study of fruit softening mechanism of
persimmon germplasm materials.
Key words: Diospyros germplasmꎬ deastringencyꎬ storageꎬ softeningꎬ enzymatic activity
柿属于柿科( Ebenaceae) 柿属( Diospyros L.) 缘关系分析ꎬ发现乐业、西林、田林、右江地区以及
落叶乔木ꎬ主要种植在热带和温带地区ꎬ中国作为 泉州、环江、中山、鹿寨、武宣、秦塘和横县的柿种
柿的原产国ꎬ有柿树 2 属 50 多种ꎬ在世界上柿种 质亲缘关系相近ꎻ并运用 Scot 基因标记法将广西
植面积最大( 高志强ꎬ2008)ꎮ 广西作为中国柿主 特有的 ‘ 油 柿’ 分 为 两 个 亚 组ꎬ 在 欧 氏 距 离 D =
要产区ꎬ柿种质资源丰富ꎬ含有‘ 柿’ ‘ 君迁子’ ‘ 油 12.09 处ꎬ将 35 份第Ⅲ亚组‘ 油柿’ 种质分为四个
柿’‘乌柿’‘毛柿’和‘野柿’等柿品种ꎮ 在广西乡 小亚组ꎬ第Ⅳ亚组‘ 农家栽培柿’ 在欧氏距离 D =
村农户房屋周围生长着多个野生‘ 油柿’ 品种ꎬ叶 9.59 处ꎬ可将 17 份‘农家栽培柿’种质分为三个小
片不具角质ꎬ叶面无光泽ꎬ具柔毛ꎬ果实接近成熟 亚组(邓立宝ꎬ2013)ꎮ
时表面附着有粘性物质ꎬ成熟时粘性物质不会消 柿属于呼吸跃变型果实ꎬ在贮藏过程中由内
失ꎬ果面多有褐斑ꎬ通常种子大且较多ꎬ种植适应 至外发生一系列转变(Smith et al.ꎬ 2002)ꎬ软化就
性广ꎬ多作为嫁接砧木(邓立宝等ꎬ2012)ꎮ 农家栽 是一 个 主 要 又 直 观 的 变 化 ( Ahmed & Labavitchꎬ
培品种多生长于房前屋后ꎬ叶片革质ꎬ表面深绿光 1980)ꎮ 果实表皮的软化是在各种大小物质共同
滑ꎬ背面淡绿有柔毛( 邓立宝等ꎬ2012)ꎬ果实中等 作用下造成的ꎬ其中细胞壁结构与内在组分的改
大小ꎬ外观品质好ꎬ无种子或种子较少ꎬ由于无人 变对其影响最为直接(Huberꎬ1983)ꎮ 细胞壁由纤
管理ꎬ 综 合 性 状 较 差 ( 邓 立 宝ꎬ 2013)ꎮ Deng et 维素和果胶等物质构成ꎬ果胶作为细胞壁主要成
al.(2015)对广西 12 个地区 189 份柿种质进行亲 分之一ꎬ随着贮藏时间的推移ꎬ果实逐渐成熟ꎬ果