【摘要】 通过解剖学和细胞学的研究发现 ,黄瓜“花打顶”茎尖部位的节数、节间长度和茎粗均减小 ,顶端幼茎细胞的伸长和伸展受到抑制 ,维管束数目增加 ,导管壁和厚角组织细胞壁明显增厚 ,顶端分生组织分化的原基数量相对减少 ,并簇生 ,顶端分生组织的体积减小 ,细胞液泡化 ,核膜、液泡膜及质体膜等部分降解 ,细胞呈现衰老趋势 ;进一步利用mRNA差异显示技术获得了黄瓜生长正常和花打顶的差异表达cDNA片段 ,Northern分析表明其中精氨酸脱羧酶 (ADC)的同源基因和叶绿体ATPase亚基III的同源基因分别属黄瓜花打顶的正调控和负调控基因更多还原

【Abstract】 In order to reveal the characteristics of the "blunt with blossom" cucumbers (BBCs) , we investigated the anatomical and cytological characteristics of the young stems and shoot tips of the BBCs by light microscopy (LM) , transmission electron microscopy (TEM) and scanning electron microscopy (SEM) procedures. In BBCs plants, the node number, internode length and the stem diameter in shoot tops all reduced, and the elongation and expansion of the stem cells were inhibited. In contrast, the wall thickness of the collenchyma cell, the number of the vessel bundles, and the number of mature vessels in young stem increased respectively. Meanwhile, the shoot apical meristem cells avacuoled, and the nuclear envelope, tonoplast, plastid envelope and endoplasmic reticulum dissolved partially. In the studies on the role of BBCs, two positive cDNA bands were obtained through mRNA differential display. Northern blot analysis showed that one cDNA fragment homologous to the chloroplast ATPase subunit III was down regulated and the other cDNA fragment homologous to the arginine decarboxylase (ADC) was up regulated in BBCs.更多还原