Mariottini Y, de Wysiecki M L, Lange C E
Centro de Estudios Parasitológicos y de Vectores (CEPAVE), UNLP - CCT La Plata CONICET, La Plata, Argentina.
Neotrop Entomol. 2011 Mar-Apr;40(2):190-6. doi: 10.1590/s1519-566x2011000200006.
Dichroplus maculipennis (Blanchard) and D. elongatus Giglio-Tos are two of the most important melanoplines in Argentina, both ecologically and economically. The postembryonic development and forage loss (consumption of Bromus brevis Ness + fallen material) caused by older nymphs (instars IV, V, VI) and adults of both species were studied under controlled conditions (30ºC, 14L:10D, 40% RH). Five nymphal instars were recorded in D. elongatus, and six in D. maculipennis. Total nymphal development was similar in both species (D. elongatus: 32 ± 0.70 days; D. maculipennis: 34.5 ± 0.37 days). Daily consumption increased from nymphal instars to pre-reproductive adult stage. In both species, pre-reproductive females had higher consumption rates than other stages considered (D. elongatus: 30.6 ± 0.56 mg dry weight/day; D. maculipennis: 48.7 ± 0.74 mg dry weight/day). In the reproductive stage, consumption decreased significantly in both sexes. When feeding, D. maculipennis let some plant material to drop, increasing total loss. The percentage of fallen material was greater in reproductive adults, representing 3.9% and 2.9% of the total daily loss for males and females, respectively. Females and males of D. maculipennis were heavier than those of D. elongatus (P < 0.05), and daily consumption was significantly higher (P < 0.05). Regardless sex and reproductive status, adults of D. maculipennis consumed 29.1 ± 0.64 mg dry weight/day on average, while one of D. elongatus 20.0 ± 0.3 mg dry weight/ day.
黄斑叉角蝗（布兰查德）和长叉角蝗吉廖 - 托斯是阿根廷在生态和经济方面最重要的两种黑蝗。在可控条件下（30℃，14小时光照：10小时黑暗，40%相对湿度）研究了这两种蝗虫老龄若虫（四龄、五龄、六龄）和成虫的胚后发育及牧草损失情况（短柄雀麦 + 掉落物的消耗量）。长叉角蝗记录有五个若虫龄期，黄斑叉角蝗有六个。两种蝗虫的若虫总发育时间相似（长叉角蝗：32 ± 0.70天；黄斑叉角蝗：34.5 ± 0.37天）。每日食量从若虫龄期到生殖前期成虫阶段逐渐增加。在这两种蝗虫中，生殖前期雌虫的食量率高于其他所考虑的阶段（长叉角蝗：30.6 ± 0.56毫克干重/天；黄斑叉角蝗：48.7 ± 0.74毫克干重/天）。在生殖阶段，两性的食量均显著下降。取食时，黄斑叉角蝗会让一些植物材料掉落，增加了总损失。掉落材料的百分比在生殖期成虫中更大，分别占雄性和雌性每日总损失的3.9%和2.9%。黄斑叉角蝗的雌虫和雄虫比长叉角蝗的更重（P < 0.05），且每日食量显著更高（P < 0.05）。无论性别和生殖状态如何，黄斑叉角蝗成虫平均每日消耗29.1 ± 0.64毫克干重，而长叉角蝗成虫为20.0 ± 0.3毫克干重/天。
