Volatiles from <i>Prunus persica</i>Flowers and Their Correlation with Flower-Visiting Insect Community in Wanbailin Ecological Garden, China

Object: To investigate the VOCs from living Prunus persica flowers of different branches and their correlation with floral insects. Special, dominant and 20 VOCs were analysed from living Prunus persica flowers captured by closely and circularly headspace way in adsorbent tubes and ATD-GC/MS on 29 April in Wanbailin Ecological Garden, China. VOCs from high altitude tree are more than low altitude in sunny site, and floral volatile constituents from upslope branches are less than downslope of the same tree on high altitude. Special floral VOCs were alpha-dimethyl-benzenemethanol, isopropyl palmitate, ethylbenzene, p-xylene, acetophenone, 3-ethyl-2-methyl-Heptane on sunny slope, and propylene glycol, decanal, hexadecane on shady slope. Dominant VOCs founded during 8 temporal quanta were toluene, hexane, 2-ethyl-1-hexanol, dodecane, pentadecane. Floral VOCs’ number from sunny slope was significantly negative correlated with flower-visiting insect community richness, abundance, diversity on sunny or shady slope, which from shady slope was significantly positive correlated with flower-visiting insect community parameters on both slopes tried dividing insects visiting floral branches from Prunus persica in sunny site with n/2 + 1 or n/2 - 1, and shady site with n/2 before sampled volatiles day. On sampled volatiles day, 2-ethyl-1-hexanol from sunny slope was significantly positive correlated with flower-visiting insect community parameters on shady slope (P Prunus persica on sunny slope, and even floral branches kept on shady slope.

不同生境访问桃花昆虫群落组成与时间动态

采用定点定树拍照法调查山西省万柏林生态园访问桃花昆虫群落丰富度与多度组成和优势物种,使用多度、单因素方差、成对样本T检验比较访问桃花昆虫群落时间动态,结果表明:2015与2016年,240组数据,访问桃花昆虫19种245头,4目,17属,4个生境都具优势物种和优势属,但不都具有特有物种和特有属。优势物种意大利蜜蜂与毛跗黑条蜂日活动呈单峰型,而中华蜜蜂、角额壁蜂、凹唇壁蜂、黄猄蚁日活动呈双峰型。低海拔样地访问桃花昆虫群落参数变化与高海拔样地不同,但相同样地群落参数变化相似。采用单峰型与双峰型物种会促进桃树结实,在高海拔样地与高龄桃园放养多种优势物种会促进桃树健康生长和结果。

桃花挥发性物质及对访花昆虫的化学响应

采取活体桃花枝顶空罩袋密闭循环式采样法和ATD-GC/MS分析桃花挥发性物质成分同时,定点定树拍照采集访花昆虫,观察照片识别访桃花昆虫物种。统计不同坡向与海拔高度样树桃花挥发性物质差异和相似性,采用双变量相关性分析桃花挥发性物质与访桃花昆虫群落丰富度、多度、多样性相关性响应。结果表明:桃花挥发性物质20种,阳坡多于阴坡,阳坡高海拔样地特异性挥发性成分最多(9种);优势成分挥发性物质己醛、甲苯和十五烷不同样树间差异显著(p<0.05);阳坡低海拔与阴坡高海拔样树桃花挥发性物质极相似(q=0.778),样树间醇类、醛类的相似性大体相同;阴坡与阳坡桃花挥发性物质种类与访桃花昆虫群落的同一指数显著相关性响应相反(p<0.01)。

晋中万柏林生态园不同海拔及干扰程度访桃花昆虫群落差异

[目的]明确万柏林生态园不同海拔及干扰程度访桃花昆虫群落组成、丰富度、多度和多样性参数差异。[方法]不同海拔高度,设置不同生境样地,定点定树拍照法采样,利用统计学分析方法,分析万柏林生态园不同海拔及干扰程度分类阶元访桃花昆虫群落物种组成、丰富度、多度及多样性。[结果]经鉴定,万柏林生态园共采集访桃花昆虫126个体,15种;游人汽车干扰强小生境、汽车干扰小生境、游人汽车干扰强生境、汽车干扰生境、游人汽车干扰弱生境、游人干扰生境中各采到访桃花昆虫7种、4种、7种、4种、10种和8种。相同年份内游人汽车干扰强小生境与游人汽车干扰强生境、汽车干扰强生境访桃花昆虫群落极相似(q=1.000),游人汽车干扰强小生境、游人汽车干扰强生境与汽车干扰小生境、汽车干扰生境访桃花昆虫群落极不相似(q=0.100);低海拔样地访桃花昆虫群落丰富度(R=10)和多度(P=46)分别低于高海拔样地访桃花昆虫群落丰富度(R=12)和多度(P=82)。[结论]不同海拔及干扰程度访桃花昆虫群落丰富度、多度和多样性参数存在差异;不同干扰程度桃园生境中特有访桃花昆虫物种可作为生境指示物种;优势访桃花昆虫物种可作为桃树传粉昆虫。万柏林生态园桃树花期与果成熟期,干扰严重,需要大力保护花期与果期桃园。