2)Damage Polyphagous Grubs in soil and adults on ground
¾ Polyphagous ¾ Grubs in soil and adults on ground 2) Damage 2) Damage
3)Life cycle Most of white grubs are 1 or 2 generations annually.Adults or larvae or both over-winter about upper 20 cm in soil. 大栗鳃金龟：Igen.six years in Sichuan; 马粪蜉金龟Aphodius subterraneus:2 gen.a year
Most of white grubs are 1 or 2 generations annually. Adults or larvae or both over-winter about upper 20 cm in soil. 大栗鳃金龟: 1 gen. six years in Sichuan; 马粪蜉金龟Aphodius Aphodius subterraneus subterraneus: 2 gen. a year. 3) Life cycle 3) Life cycle
Holotrichia diomphalia 1 gen.two years in northern China, both adults and larvae overwinter in soil; 1 gen.a year in southeastern China,adults overwinter in soil. Adults appear from early June to late July. 13
13 Holotrichia Holotrichia diomphalia diomphalia 1 gen. two years in northern China, both adults and larvae overwinter in soil; 1 gen. a year in southeastern China, adults overwinter in soil. Adults appear from early June to late July
Newly hatched Ovipositing Hatching peak larvae begin to damage peak of eggs from late to mid from early June Aug. crops in Aug.→】 Larvae to late Jul Mid Oct. 华北大黑鳃金龟生活史 5/上，17℃成虫 盛发 大部分幼虫秋季 完成一代 极少部化蛹羽化 春季成虫 越冬幼虫次年春季上升为害， 10cm土， 6月开始化蛹，9月达到成虫羽 10℃以下幼 虫越冬 成虫越冬 15℃ 化盛期，当年羽化的成虫不出 土即在土壤中越冬
14 春季成虫 10cm土，14- 15℃ 5/上，17℃成虫 盛发 Ovipositing peak of eggs from early June to late July Hatching peak from late to mid Aug. 10℃以下幼 虫越冬 成虫越冬 Larvae 大部分幼虫秋季 完成一代 极少部化蛹羽化 华北大黑鳃金龟生活史 Newly hatched hatched larvae begin larvae begin to damage to damage crops in Aug. crops in Aug. Mid Oct. Mid Oct. 越冬幼虫次年春季上升为害， 6月开始化蛹，9月达到成虫羽 化盛期，当年羽化的成虫不出 土即在土壤中越冬
Holotrichia parallela 1 gen.a year.Most over-wintering third instar larvae found in soil;a few adults are found too. over-wintered larvae pupate mainly in mid-May.No significant injury found in spring.Adults appear from mid-June to mid- August.Larvae feed severely on crops from late June to late August
15 Holotrichia Holotrichia parallela parallela 1 gen. a year. Most over-wintering third instar larvae found in soil; a few adults are found too. over-wintered larvae pupate mainly in mid-May. No significant injury found in spring. Adults appear from mid-June to midAugust. Larvae feed severely on crops from late June to late August