Reproductive Phenology Of Ficus Pumila And Life Cycle Of Pollinating Wasps In Zhejiang Province

Phenology is the study of periodic plants and animals life cycle events and how these are influenced by seasonal and interannual variations climatic factors. Reproductive phenology of plants describes the temporal pattern of flowering, fruiting and seed maturing. Plant reproductive phenology has a close relationship with its pollinating animals.Figs and their pollinating wasps are among the most tightly linked interspecific interactions. Each fig species is pollinated by the unique specialized fig wasps, and fig wasps developed in syconium of fig species. The fig-fig wasp system is a model system for testing co-evolution of reproductive phenology. Reproductive phenology of figs and the life cycle of pollinating wasps may provide important information for the understanding of the reproductive basis of the mutualists which are facing global warming.Ficus pumila and the pollinating wasps are widely distributed in southeastern China. Since 1980s, researchers had revealed some characteristics in symbiotic relationship between F. pumila and its pollinating wasps in Zhejiang, Taiwan and Fujian of China. However, there are some different opinions and conclusions about the flowering phenology of F. pumila and the life cycle of pollinating wasps.In this study, we selected two mainland populations-Tiantong of Ningbo(28 individuals), Linhai of Taizhou (23 individuals), and two island populations-Taohua island of Zhoushan (22 individuals), Dongji island of Zhoushan (15 individuals) to investigate the reproductive phenology of F. pumila, and the life cycle of pollinating wasps, tried to understand their symbiotic relationship.The main conclusions were as follows:1) Reproductive phenology of F. pumila and the life cycle of pollinating wasps are always closely related. Male figs flower three times per year, while most female figs once. In spring, female F. pumila individuals produce abundant syconia, while male F. pumila individuals have a small crop. However, in summer and autumn, male F. pumila individuals have a mass crop. In general, crops of male F. pumila individuals are in the order of second crop> first crop> third crop. In spring, most wasps entered female syconia to pollination, while in summer and autumn, wasps entered male syconia to oviposit. This rule remains the same year after year.2) Reproductive capacity of pollinating wasps of F. pumila was strongly, which can breed three generations per year mostly. The offspring amount are in the order of second generation> first generation> third generation. Most of wasps'offspring were female, and the sex ratio about 0.34-0.42. Moreover, the reproduction of pollinating wasps and the reproductive phenology of F. pumila can influence each other.3) The diameter, length and weight of syconia were all increased with the time. There were significantly difference in diameter and length of male syconia at phase D among four populations, and at phase B there were significantly difference in diameter between LH and DJ F. pumila populations. Totally, at the first generation of syconia, female grew rapidly than male one, and female syconia were about twice of male syconia. When the pollinating wasps became emergence, they will find the receptive syconia by the flavor in spite of the size of syconia.At phase E, in female syconia,1000-seed weight was significantly correlated with diameter and fresh weight. Thickness of receptacle may be the important factor to affect the number of seeds, besides the diameter.4) Three cryptic pollinators were co-existence in Zhejiang province. Sp. A and Sp. B were distributed in LH, Sp. A was distributed in TT, Sp. C was distributed in DJ, and Sp. A and Sp. C were distributed in TH. In spring, Sp. B emerged first, followed by Sp. A and Sp. C. In Taohua island, Sp. A emerged about 10 days earlier than Sp. C.