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

Abstract

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 < 0.001). After sampled day, hexanal, toluene, dodecane were significantly negative correlated with SUSR, SUSA, SUSD, and positive with SHSR, SHSD, while tetradecane, pentadecane were positive related to SUSR, SUSA, SUSD with n/2 − 1 dividing insects visiting floral branches, but reversely with n/2 + 1 dividing insects visiting floral branches. We concluded that special and dominant volatiles applied to lure flower-visiting insects to promote pollination, and odd floral branches should be kept for every tree when pruning the Prunus persica on sunny slope, and even floral branches kept on shady slope.