Study On Components And Function Of The Aril And Sarcotesta In Seven Plants

Fleshy aril (typical aril) and sarcotesta are plants structure, which formed in the long process of evolution in order to meet the animals spread their seeds. It is difficult to distinguish from their shape characteristic. The origin and evolution relationship is there has been much controversy. In this paper, we choose Celastraceae plants Euonymus alatus, E. bungeanus, Celastrus orbiculatus as the aril research object and select gymnosperms Cycas revoluta, Ginkgo biloba and more primitive angiosperms Magnoliaceae Magnolia denudata, M. biondii as the sarcotesta research object, respectively from morphological characteristics, the chemical composition of aril and sarcotesta, water absorption and water loss characteristics of seed, effects on seed germination of aril five aspects, has carried on the preliminary exploration of biology and ecology function. The main results were as follows:1. Sarcotesta of Cycas revoluta, Ginkgo biloba, Magnolia denudata and M. biondii on seed weight of the proportion is larger, which accounts for almost half of the seed quality. This show their seed propagation had to give greater cost. And the proportion of aril is relatively small, which accounts for about 9% of the seed quality.2. There kinds of Celastraceae plant aril composition of fatty acid content are the highest, next in alcohol. Magnolia denudata and M. biondii sarcotesta of terpene and alcohol compounds in the most; Ginkgo biloba sarcotesta aromatic component content in the highest; Cycas revoluta sarcotesta fatty acid and aldehyde content in the highest.3. Sarcotesta structure for seed has certain water and the water storage function, in a certain period of time can reduce the water loss and the water loss rate of the seed, and the presence of aril has no significantly effect on the water storage aspects of seed itself.4. The presence of aril has inhibitory effect on its seed germination. With aril of seeds were 10 days later than without aril of seeds to germinate time and germination rate low 14-18%. The sarcotesta extract has obvious inhibitory effect to seed germination.5. The sarcotesta in function is a kind of similar structure to pulp of fleshy fruit, which has the rich chemical compositions and plays an important role in its seed dispersal. It not only can attract birds spread their seeds, also has certain inhibitory effect on seed germination. Its color and inclusions may important factors to attract communicators.