Williams L, Evans P E, Bowers W S
USDA-ARS, Southern Insect Management Research Unit, P.O. Box 346, Stoneville, Mississippi 38776-0346, USA.
J Chem Ecol. 2001 Feb;27(2):203-16. doi: 10.1023/a:1005692502595.
Volatile components of Pachycoris stallii scent gland secretions and the bug's host plant, Croton californicus, were identified by gas chromatography and mass spectroscopy. The predominant compounds isolated from C. californicus fruit and leaves were beta-myrcene and beta-caryophyllene. Metathoracic gland secretions of P. stallii contained mostly (E)-2-hexenal, (E)-4-oxo-2-hexenal, (E)-2-hexenyl acetate, and n-tridecane. In males, n-tridecane was present throughout the metathoracic gland, but in females this compound was found only in the median reservoir/accessory gland. (E)-2-Hexenal was present throughout the gland of female bugs, but in males was primarily present in the median reservoir/accessory gland. (E)-4-Oxo-2-hexenal and n-dodecane were isolated from the median reservoir/accessory gland of male and female bugs. Metathoracic glands were sexually monomorphic. Data from chemical analyses and anatomical observations suggest that dorsal abdominal glands of adults were apparently obsolescent. In nymphs, dorsal abdominal glands produced (E)-2-hexenal, (E )-4-oxo-2-hexenal, n-dodecane, n-tridecane, and tetradecanal. The proportion of the predominant constituent, (E)-4-oxo-2-hexenal, decreased from 72% in the first instar to 47% in the fourth instar. Proportions of tetradecanal and n-tridecane were greater in the fourth instar than in the first instar. Observations of dissected glands indicated that median and posterior dorsal abdominal glands of all nymphal instars were more developed than anterior dorsal abdominal glands. Scanning electron micrography revealed the presence of polygonal microsculpturing on the integument surrounding the ostioles of metathoracic and dorsal abdominal glands. Chemical, anatomical, and behavioral data indicated that P. stallii has a chemical defense system based on short-chain carbonyl compounds and that this system is directed against arthropods. The abundance of arthropod natural enemies apparently has forced P. stallii to maintain this defense system despite feeding on a toxic host plant.
通过气相色谱法和质谱法鉴定了斯氏厚蝽（Pachycoris stallii）臭腺分泌物及其寄主植物加州巴豆（Croton californicus）的挥发性成分。从加州巴豆果实和叶片中分离出的主要化合物为β-月桂烯和β-石竹烯。斯氏厚蝽的后胸腺分泌物主要包含（E）-2-己烯醛、（E）-4-氧代-2-己烯醛、（E）-2-己烯基乙酸酯和正十三烷。在雄性个体中，正十三烷存在于整个后胸腺中，但在雌性个体中，该化合物仅在中间储液囊/附腺中被发现。（E）-2-己烯醛存在于雌性蝽的整个腺体中，但在雄性个体中主要存在于中间储液囊/附腺中。（E）-4-氧代-2-己烯醛和正十二烷从雄性和雌性蝽的中间储液囊/附腺中分离得到。后胸腺在性别上是单态的。化学分析和解剖观察数据表明，成虫的腹部背腺显然已经退化。在若虫中，腹部背腺产生（E）-2-己烯醛、（E）-4-氧代-2-己烯醛、正十二烷、正十三烷和十四醛。主要成分（E）-4-氧代-2-己烯醛的比例从一龄若虫时的72%降至四龄若虫时的47%。十四醛和正十三烷在四龄若虫中的比例高于一龄若虫。对解剖后的腺体观察表明，所有若虫龄期的中间和后部腹部背腺比前部腹部背腺更发达。扫描电子显微镜显示，后胸腺和腹部背腺气门周围的体表存在多边形微雕。化学、解剖和行为数据表明，斯氏厚蝽具有基于短链羰基化合物的化学防御系统，且该系统针对节肢动物。尽管以有毒寄主植物为食，但节肢动物天敌的大量存在显然迫使斯氏厚蝽维持这种防御系统。
