Research Progress of Maternal Environmental Effects in Resource-based Regions

Heavy metal pollution is common in resource-based regions.However,the morphological,physiological and biochemical mechanisms of plants transmitting environmental information to their offspring in environments polluted by heavy metals have not been studied yet.Taking soybean,an annual self-pollinated plant in Huang-Huai-Hai region,as the research object,the morphological,physiological and biochemical indexes and heavy metal enrichment and distribution characteristics of plants under heavy metal stress were monitored continuously for about three generations,and the trans-generational differences of soybean reproduction,vegetative growth,stress resistance and life cycle in heavy metal stress environment were elucidated.The results will be helpful to better understand the long-term adaptive strategy of plants to heavy metal stress and provide the theory basis for ecological security of soybean and other crops under heavy metal stress.

Offspring Sex Is Not Determined by Gestation Temperature in a Viviparous Lizard(Eremias multiocellata) from the Desert Steppe of Inner Mongolia

Sex-determining systems show a striking diversity not only among species, but also among popula tions. In reptiles, sex-determina tion is a continuum, from tempera ture-dependent sex determination(TSD) to genetic sex determination(GSD).The multi-ocellated racerunner(Eremias multiocellata)is reported to be a cryptic ZZ/ZW chromosomal TSD species, with male-biased sex ratios at high temperatures in two Gansu populations. However, the generality of the sex-determining pattern in different populations of this species remains unclear. To investigate the mode of sex determina tion in a popula tion of E.multiocellata from the desert steppe of Inner Mongolia,we first identified sex chromosomes via comparative genomic hybridization(CGH). We then conducted a thermal manipulation experiment to determine the effect of gestation temperature on offspring sex ratios.From the CGH studies we found that lizards from the Inner Mongolia population possessed ZZ/ZW sex chromosomes. However, our thermal manipulation experiment showed that gestation temperature did not affect the sex ratio of neonates in this population. In combination, these results rule out TSD in the Inner Mongolia population of E. multiocellata, and suggest that there is widespread geographic variation in the sexdetermining system of this species.