Medeiros Lenice, Megier Gabriela A
Depto. de Biologia e Química, Univ. Regional do Noroeste do Rio Grande do Sul, Ijuí, RS.
Neotrop Entomol. 2009 Jul-Aug;38(4):459-63. doi: 10.1590/s1519-566x2009000400003.
The Neotropical brown stink bug Euschistus heros (F.) can reach high densities in some soybean areas in Brazil. Besides soybean, it also feeds on other plants, but little is known on the alternative hosts of E. heros in Rio Grande do Sul state. In this study, wild non-cultivated hosts of E. heros at Norwest of Rio Grande do Sul state were determined, and the E. heros performance was compared when fed on soybean and on wild hosts. Bugs were sought in plants located inside and on the edge of soybean fields during 2004/2005 and 2005/2006 seasons. Adults were recorded feeding on seeds of Amaranthus retroflexus (Amaranthaceae), and on fruits of three Solanaceae, mainly Vassobia breviflora. Immature survivorship on soybean (86.7%) and on V. breviflora (81.8%) was the same, but nymphs fed on A. retroflexus did not reach adulthood. The host plant used during immature development greatly affected adult weight, with V. breviflora yielding the heaviest adults; however, adult survivorship and longevity when fed on different host plants were the same. Females fed on soybean laid larger egg masses than those fed on V. breviflora , but the overall fecundity was not affected.
新热带区褐蝽Euschistus heros（F.）在巴西一些大豆种植区的密度可能会很高。除了大豆，它还以其他植物为食，但对于南里奥格兰德州E. heros的替代寄主却知之甚少。在本研究中，确定了南里奥格兰德州西北部E. heros的野生非栽培寄主，并比较了E. heros取食大豆和野生寄主时的表现。在2004/2005年和2005/2006年季节，在大豆田内部和边缘的植物上寻找虫子。记录到成虫取食反枝苋（苋科）的种子以及三种茄科植物的果实，主要是短花假茄。在大豆上（86.7%）和在短花假茄上（81.8%）的未成熟个体存活率相同，但取食反枝苋的若虫未发育到成虫阶段。未成熟发育期间所使用的寄主植物对成虫体重有很大影响，短花假茄培育出的成虫最重；然而，取食不同寄主植物时成虫的存活率和寿命相同。取食大豆的雌虫产下的卵块比取食短花假茄的雌虫产下的卵块大，但总体繁殖力不受影响。
