[en] Mesocosm experiments were conducted to examine belowground responses of Phragmites australis and Suaeda salsa to the combined stresses of increased salinity and water depth. The results demonstrated that: (1) belowground biomass of P. australis responded negatively to both increased salinity and water depth, whereas belowground biomass of S. salsa mainly responded negatively to increased water depth; (2) belowground biomass of S. salsa negatively responded to increased water depth more strongly than that of P. australis, thus S. salsa might disappear before P. australis in wetlands experiencing prolonged water-logging; (3) P. australis and S. salsa responded to increased salinity and/or water-logging by shifting their resource allocations towards aboveground biomass; (4) belowground biomass of P. australis tended to have more negative responses to increased salinity and water depth at deeper versus shallower soil depths, hindering P. australis from utilizing resources in deeper soil; in contrast, belowground biomass of S. salsa tended to have more negative responses to increased water depth at shallower versus deeper soil depths, greatly decreasing the overall root density and thereby increasing the chance of uprooting disturbance to S. salsa. These responses would accelerate sediment loss due to compromised sediment-binding abilities of P. australis and S. salsa, leading to an adverse positive feedback between environmental changes associated with sea level rise and performance of P. australis and S. salsa, resulting in faster deterioration of coastal wetlands than might otherwise be expected. (author)

[en] Interspecific hybridization is an effective method of fruit tree breeding for new varieties. In order to understand interspecific hybridization compatibility, abortive period, and the development of hybrid fruit from crosses between Huaren apricot and almond, we conducted crossing experiments. The growth condition of the pollen tube was observed by fluorescence electron microscopy, and the abortion rate and developmental characteristics of hybrid fruit were analyzed in different stages. The results showed that the pollen of Huaren apricot and almond were able to germinate, and that the pollen tubes can enter into the embryo sac of the other species. After four weeks of cross pollination, the average fruit-setting rate of the interspecific hybrid was 7.06% using Huaren apricot as female parent, which was 24.39% of the intraspecific hybridization rate; mature fruit accounted for 17.54% of the young fruit. When almond was used as the female parent, the average fruit-setting rate of interspecific hybridization was 6.33%, which was 46.10% of the intraspecific hybridization, and the mature fruit accounted for 5.17% of the young fruit. However, the embryos were aborted after the fruit ripened. The fruit of interspecific hybrids with Huaren apricot as the female parent grew slower than that of the intraspecific hybrid. In addition, the fruit was smaller when mature and embryo development was normal in the former as compared with that in the latter. The fruit development after interspecific hybridization using almond as the female parent was consistent with that of the intraspecific hybrids. However, the embryonic development gradually stopped, and malformed and normal embryos could not be formed. There is a high potential for interspecific hybridization between Huaren apricot and almond. Particularly, using Huaren apricot as a female parent, a well-developed embryo can be obtained. (author)