杨梅果实发育与糖的积累及其关系研究

Studies on the fruit development and its relationship with sugar accumulation in bayberry fruit

以东魁、荸荠种、水梅为试材,研究了杨梅果实发育与糖积累及其关系。根据杨梅果实大小的增加将果实发育大致分为3个阶段,呈双“S型”曲线动态变化:第1阶段(约盛花32d前)果实纵、横径增长最快;第2阶段(32-63d)果核发育硬化,果重增加明显;第3阶段(63d至成熟)果实进入快速增长高峰,果重迅速增加,光合产物在果实中迅速积累。杨梅果实中积累的糖主要是蔗糖,果糖和葡萄糖仅占总糖的1/4,蔗糖含量在发育初期和中期都较低,盛花52d后开始快速积累直至果实成熟,东魁高于水梅、荸荠种;葡萄糖和果糖变化大致保持同步,第1阶段较高,第2阶段降到最低,第3阶段迅速积累达到最高,与蔗糖积累基本保持一致,成熟时东魁与水梅较荸荠种高且相近。杨梅果实中酸性转化酶(Ivr)与中性转化酶(Nvr)活性变化趋势相同,幼果早期最高,中期降低后维持较低活性直至成熟。品种间pH值变幅相似,果实发育第1阶段最高,第2阶段降到最低,转色后上升。相关分析表明:果实发育动态与蔗糖、葡萄糖、果糖的积累存在着极显著的相关关系,其中果实横径的增加与果实糖积累组分中蔗糖的变化2者间相关性最大(r=0.93255**)。

Studies were carried out with 3 bayberry cuhivars （Myrica rubra Sieb. et Zucc.） ： Dongkui, Biqizhong and Shuimei. Results showed that the fruit development could be divided into 3 stages in a “S” curve. At stage 1, in the period about 32 days after full bloom （DAF）,the increase of fruit vertical and horizontal diameter were the fastest. At stage 2,from 32 to 63 days after DAF, fruit stone hardened and fruit weight increased distinctly. At stage 3, fruit growth and development arrived at the peak, fruit weight increased immediately, and photosynthetic products accumulated quickly into fruits. The sugars in fruit were mostly accumulated with sucrose. Fructose and glucose were only one fourth of total sugar contents. Sucrose was lower during early and middle fruit development stage and rapidly accumulated after 52 DAF. This sugar content of Dongkui matu- rity fruit was higher than that of Shuimei and Biqizhong. Fructose and glucose contents were consistently higher at stage 1 and lower at stage 2, then were accumulated rapidly till ripe. Their content in Dongkui and Shuimei maturity fruit were higher than Biqizhong. The change trend of activity of acid invertase（Ivr） and neutral invertase（Nvr） were consistently kept higher at young fruit, lower at middle stage then maintained lower activity. The pH trend in different cultivars was similar the highest at stage 1 and the lowest at stage 2 then was increased after turned red. The correlation results showed that there was extremely significant correlation between the characters of fruit development and the accumulation of sucrose, glucose and fructose. The increasing of fruit horizontal diameter had the closest correlation with the change of sucrose （r=-0.932 55^＊＊）.