Embrapa Recursos Genéticos e Biotecnologia, Caixa Postal 02372, CEP 70770-900, Brasília, DF, Brazil.
Micron. 2010 Jun;41(4):289-300. doi: 10.1016/j.micron.2009.11.009. Epub 2009 Dec 4.
The neotropical stink bugs, Euschistus heros, Piezodorus guildinii and Edessa meditabunda, are important pests of soybean and other crops throughout Central America and in South America from Northern Argentina to Brazil. Mate finding and host plant location in these species depend largely on their chemical communication, and semiochemicals are important mediators of these behaviors. In this study scanning electron microscopy was used to examine the external morphology, distribution and abundance of antennal sensilla on males, females and 5th instar nymphs of these species. Nine morphologically different sensilla types were found: trichod sensilla, type 1 and 2 (ST1 and ST2), long and short basiconic sensilla (SB1, SB2, and SB3), slit-tipped and knob-shaped basiconic sensilla, long chaetic sensilla (Sch) and coeloconic sensilla (Sco). Differences were detected in the abundance and arrangement of the sensilla over the antennal segments in individuals of the same species and among the species studied. The Sch, Sco and the slit-tipped and knob-shaped basiconic sensilla accounted for the major difference in sensilla types among the species. The ST1 was the most abundant type and was restricted to the flagellum. The pedicel of E. heros differs from the pedicels of P. guildinii and E. meditabunda mainly by the absence of Sch. There was a sexual dimorphism in ST1, SB1 and SB2, and this may be an indicative of their roles in detection of male-produced sex pheromone and odors derived from the host plants. The SB2 was lacking in the antennal tip of both sexes and 5th instar nymphs, but was abundant on the second flagellar segment of females of the three species. The same types of sensilla were found on 5th instar nymphs, but always in significantly lower numbers. The morphology and putative functions of each sensilla were compared and discussed.
新热带臭虫，包括英雄异皮臭虫、胫节皮臭虫和中褐异皮臭虫，是中美洲和南美洲从阿根廷北部到巴西的大豆和其他作物的重要害虫。这些物种的交配和寄主植物定位在很大程度上依赖于它们的化学通讯，而信息素是这些行为的重要调节因子。在这项研究中，使用扫描电子显微镜检查了这些物种的雄性、雌性和 5 龄若虫的触角上感觉器的外部形态、分布和丰度。发现了 9 种形态不同的感觉器类型：毛形感觉器、1 型和 2 型（ST1 和 ST2）、长和短的刺形感觉器（SB1、SB2 和 SB3）、狭口端和球形刺形感觉器、长刺形感觉器（Sch）和腔锥形感觉器（Sco）。在同一物种的个体之间以及在所研究的物种之间，发现了触角节上感觉器的数量和排列存在差异。Sch、Sco 和狭口端和球形刺形感觉器是物种之间感觉器类型差异的主要原因。ST1 是最丰富的类型，仅限于触角鞭节。E. heros 的柄节与 P. guildinii 和 E. meditabunda 的柄节主要不同之处在于缺乏 Sch。ST1、SB1 和 SB2 存在性别二态性，这可能表明它们在检测雄虫产生的性信息素和来自寄主植物的气味方面发挥作用。两性和 5 龄若虫的触角顶端都缺乏 SB2，但在三种雌性的第二触角鞭节上非常丰富。5 龄若虫上也发现了相同类型的感觉器，但数量总是明显较少。比较和讨论了每种感觉器的形态和推测功能。
