董俊娜 谢柳青 楚文清 于旭东 蔡泽坪 罗佳佳 瞿倩

摘  要：木本植物茎的发育在木材形成中具有重要意义。以菠萝蜜叶绿素缺失突变体幼苗（Chlorophyll deficient mutant， CDM）为研究材料，选取正常幼苗作为对照（Control check， CK），观察并测量其株高和基部茎粗。使用石蜡切片法和光学显微技术对茎各节间进行观察，测量木质部、韧皮部、表皮和周皮的厚度，比较CDM与CK之间的差异。结果显示，CDM的株高和基部茎粗的增长受到一定的抑制，各节间木质部、韧皮部以及周皮的厚度均减小;相比次生木质部，次生韧皮部的抑制作用更显著。

关键词：菠萝蜜;叶绿素缺失突变体;茎;解剖结构

中图分类号：S667.8      文献标识码：A

Structural Analysis of the Stem of the Chlorophyll Deficient Mutant from Artocarpus heterophyllus Seedlings

DONG Junna1， XIE Liuqing2， CHU Wenqing1， YU Xudong1， CAI Zeping1*， LUO Jiajia2，3， QU Qian1

1. College of Forestry， Hainan University / Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants， Ministry of Education， Haikou， Hainan 570228， China; 2. College of Tropical Crops， Hainan University， Haikou， Hainan 570228， China; 3. Tropical Crops Genetic Resources Institute， Chinese Academy of Tropical Agricultural Sciences / Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China， Ministry of Agriculture & Rural Affairs， Danzhou， Hainan 571737， China

Abstract： The stem development of woody plants plays an important role in wood formation. In this study， the seedlings of the chlorophyll deficient mutants （CDM） of Artocarpus heterophyllus were selected as the research material and normal seedlings were selected as the control check （CK） to observe and measure plant height and basal stem diameter. The internodes of seedlings were observed by paraffin section and optical microscopy. The thickness of xylem， phloem， epidermis and periderm were measured， and the difference between CDM and CK was compared. The results showed that the increase of plant height， basal stem diameter of CDM were inhibited to some extent， and the thickness of xylem， phloem and periderm of each internode decreased. Compared with the secondary xylem， the inhibition of secondary phloem was more significant.

Keywords： Artocarpus heterophyllus; chlorophyll deficient mutant; stem; anatomic structure

DOI： 10.3969/j.issn.1000-2561.2021.06.021

茎在植株中起到支撑和运输的重要作用，且在木材形成过程中具有重要意义[1]。木本植物茎的生长包括初生生长和次生生长两部分。初生生长发生在茎的幼嫩组织中，茎顶端分生组织细胞的分裂和伸长共同决定了茎的伸长，使植株长高。在此过程中，产生初生木质部和初生韧皮部，并分化出表皮。次生生长在初生生长完成之后发生，此时维管形成层分别向内、向外产生次生木质部和次生韧皮部，同时周皮取代表皮，于是茎不断增粗[2-3]。

光合作用为绿色植物的生长发育提供必要的物質和能量[4-5]。叶绿素是光合作用的重要色素，在光能的吸收、传递和转换过程起着重要的作用[6-7]。叶绿素缺乏会导致植物对光能的利用率下降，从而影响其正常的能量供应，在植物外观形态上表现为叶片及茎出现黄化或白化现象[8]。……