Department of Plant Protection, University of Tehran, Karaj, Iran.
Micron. 2012 Apr;43(5):631-7. doi: 10.1016/j.micron.2011.11.008. Epub 2011 Dec 8.
The Sunn pest, Eurygaster integriceps Put. (Hemiptera: Scutelleridae), is a key pest of wheat in the Middle East and some other areas which causes severe qualitative and quantitative damage. The objective of the current work is to describe the morphology of the midgut of E. integriceps adult. Microscopic studies revealed that foregut consists of oral cavity, pharynx and oesophagus likely other phytophagous Hemiptera. In the Midgut, four anatomical regions could be identified: the first ventriculus (V1), the second ventriculus (V2), the third ventriculs (V3), and the fourth ventriculus (V4). The microvilli and perimicrovillar membrane (PMM) were found in V1-V3 regions with columnar cells characterized by presence of mitochondria, rough endoplasmic reticulum and basal infoldings in the basal portion. However, V2 and V3 showed less developed basal plasma membrane infoldings. Three cell types: columnar, endocrine and regenerative cells were found in V1-V3. The V4 region showed different histological features from the other three midgut regions by showing a vacuolated epithelium with crypts storing symbiotic bacteria. The hindgut had a short ileum followed by a well-developed rectum with an epithelial cell layer and a thin cuticular intima. The current results suggest V1-V3 midgut regions play a role in enzyme and absorption, whereas V4 seems to have no function in digestion.
沙蝽，Eurygaster integriceps Put.（半翅目：盾蝽科），是中东和其他一些地区小麦的主要害虫，会造成严重的定性和定量损害。本研究的目的是描述 E. integriceps 成虫中肠的形态。显微镜研究表明，前肠由口腔、咽和食道组成，可能还有其他植食性半翅目昆虫。在中肠中，可以识别出四个解剖区域：第一胃（V1）、第二胃（V2）、第三胃（V3）和第四胃（V4）。微绒毛和周缘微绒毛膜（PMM）在前肠的 V1-V3 区域发现，柱状细胞具有线粒体、粗糙内质网和基底部的基底内褶。然而，V2 和 V3 的基底质膜内褶发育较少。在 V1-V3 中发现了三种细胞类型：柱状细胞、内分泌细胞和再生细胞。V4 区域与其他三个中肠区域的组织学特征不同，表现为具有储存共生细菌的隐窝的空泡化上皮。后肠有一个短的回肠，随后是一个发育良好的直肠，具有上皮细胞层和薄的角质内缘。目前的结果表明，V1-V3 中肠区域在酶和吸收方面发挥作用，而 V4 似乎在消化方面没有功能。
