The Desiccation-tolerance's Obtainment And Changement Of Alocasia Macrorrhiza Seed Development

Seed development is basis for subsequent dehydration and germination behavior, while dehydration behavior is key making strategy for study and storage of seed. It has been known that the acquirement of desiccation tolerance and the initiation of maturation dehydration have closely related with the changes during development, maybe gradually came about physiological and morphological change during seed development. The aim of this work is to reveal the mechanism of desiccation tolerance development, through relationship analyses between seed development and its desiccation tolerance changes, during the whole seed maturation process of Alocasia macrorrhiza, in order to provide a theoretical basis for building possible techniques for long-term storage of Alocasia macrorrhiza germplasm resource.The experimented Alocasia macrorrhiza was planted in Xishuangbanna Tropical Botanical Garden's rainforest and south medical garden. Study was focused on the changes of seed desiccation tolerance in different seasons (dry season and rain season), and seed germination and storage behaviour. Main results were as follows:1. There was considerable variability in the time of maturation between raniy-season and dry-season, the rainy-season just need 95DAF, but in dry-season, 137DAF. The 1000-fruit weight in rainy-season was much higher than in dry-season.2. Seeds germinated well with a temperature range from 20~35℃under alternationg photoperiod(14h light/10 h dark, 12ūmol m-2s-1), while the best germination percentage obtained between 25~30℃. However, seed germination was not significantly promoted by light, but establishment of seedling was promoted by light.3. The semilethal water content of dry-season mature seeds was lower than that of rain-season seeds, 0.24 gH2Og-1DW and 0.27 gH2Og-1DW, respectively. The dry-season mature seeds showed a higher desiccation tolerance, the behavior of dehydration tolerance mightbe relate with its habitat.4. The seed of alocasia macrorrhiza obtained desiccation during the seed development, so it was a quantitative characteristic, not was mutation characteristic.5. It was shown obviously the recalcitrant characteristics of Alocasia macrorrhiza seed,though can survive at 4℃, not conservation long term, maybe recalcitrant seed.6. During the whole development of alocasia macrorrhiza, there was link between fruits and seeds, there was not PVS stage.