关键词: 后河自然保护区, 珍稀濒危植物, 分形, 分布格局, 分形特征, 计盒维数拐点尺度

Abstract: Serangium japonicum is an important predator of whiteflies in China.In this study,the Bemisia tabaciattacking behavior of S.japonicum adults and larvae was observed by a videocassette recorder.The results showed that the predatory behavior of S.japonicum adults was characteristic with six events,i.e.,walking,feeding,clearing,resting,vibrating wings,and excreting.The starved larvae of S.japonicum was fond spending all times in feeding and walking on host eggs,with no time in resting or clearing throughout the process.The time included in feeding and walking was not significant different among different instars of S.japonicum.The handing time per egg decreased with S.japonicum larvae developed from instar I to Ⅳ,but differed little between instar Ⅲ and Ⅳ.The starved females of S.japonicum spent longer time on egg feeding，but less time on clearing,resting and walking than satiated females.The time for starved female to predate on B.tabaci nymphs and pupae increased as the host nymphs developed.

Key words: Houhe Nature Reserve, Rare and endangered plant, Fractal properties, Box counting dimension, Inflexion scale