‘冠军’芦笋雌雄花发育过程中内源激素和多胺#br# 含量的变化

 以‘冠军’芦笋为试材,研究雌花、雄花发育过程中内源激素和多胺含量的变化,结果表 明,在芦笋雌花发育过程中,GA3 含量始终高于雄花,ABA、ZR 和IAA 含量从两性发育期到单性发育期 呈降低趋势;而雄花中的ABA、ZR 和IAA 含量则从两性发育期到单性发育期迅速上升。雌花GA3/ABA、 GA3/IAA、GA3/ZR 比值在两性发育期较雄花低,到单性发育期迅速升高,表明较高水平的GA3 和低水平 的ABA、IAA、ZR 与雌性器官选择性发育有关,而较高水平的ABA、ZR 和IAA 与雄性器官选择性发育 有关。雌花发育过程中多胺Spd、Put 和Spm 含量均呈先迅速升高后又下降的趋势,而雄花中3 种多胺的 含量相对稳定,高水平的Spm、Spd 和Put 与雌性器官发育有关。     

Ontogenic and morphological study of gonadal formation in genetically-modified sex reversal XYPOS mice

Mammalian sexual fate is determined by the presence or absence of sex determining region of the Y chromosome (Sry) in the “bipotential” gonads. Recent studies have demonstrated that both male and female sexual development are induced by distinct and active genetic pathways. Breeding the Y chromosome from Mus m. domesticus poschiavinus (POS) strains into C57BL/6J (B6J) mice (B6J-XY^POS) has been shown to induce sex reversal (75%: bilateral ovary, 25%: true hermaphrodites). However, our B6N-XY^POS mice, which were generated by backcrossing of B6J-XY^POS on an inbred B6N-XX, develop as males (36%: bilateral testis with fertility as well as bilateral ovary (34%), and the remainder develop as true hermaphrodites. Here, we investigated in detail the expressions of essential sex-related genes and histological features in B6N-XY^POS mice from the fetal period to adulthood. The onsets of both Sry and SRY-box 9 (Sox9) expressions as determined spatiotemporally by whole-mount immunohistochemistry in the B6N-XY^POS gonads occurred 2–3 tail somites later than those in B6N-XY^B6 gonads, but earlier than those in B6J-XY^POS, respectively. It is possible that such a small difference in timing of the Sry expression underlies testicular development in our B6N-XY^POS. Our study is the first to histologically show the expression and ectopic localization of a female-related gene in the XY^POS testes and a male-related gene in the XY^POS ovaries. The results from these and previous experiments indicate that the interplay between genome variants, epigenetics and developmental gene regulation is crucial for testis development.     

Restoration Affect Soil Organic Carbon and Nutrients in Different Particle‐size Fractions

Desertification is reversible and can often be prevented by adopting measures to control the causal processes. Desertification has generally decreased in most of the arid and semiarid areas of China during the last few decades because of the restoration of degraded vegetation and soil nutrients. However, little is known about the responses of soil nutrients in different particle‐size fractions to the restoration process and about the importance of this response to the restoration of bulk‐soil nutrients. In this study, we separated bulk‐soil samples in different sieve fractions: coarse‐fine sand (2·0–0·1 mm), very fine sand (0·10–0·05 mm) and silt + clay (<0·05 mm) fractions. Soil organic carbon (SOC), N, P and K contents stored in the silt + clay were greater than the contents of non‐protected nutrients in the coarser fractions. During the restoration of desertified land, the content and stability of bulk‐soil SOC, total N and P and available N, P and K increased with increasing nutrient contents in all fractions. Topsoil nutrients stored in coarse‐fine sand and very fine sand fractions were more sensitive than those stored in the silt + clay fraction to the fixation of mobile sandy lands and vegetation recovery. The changes of bulk‐soil nutrients and their stability were decided by the soil nutrients associated with all particle‐size fractions. Path analysis revealed that SOC and total nutrients in very fine sand and available nutrients in coarse‐fine sand were the key factors driving the soil recovery. These results will help us understand soil recovery mechanisms and evaluate the degree of recovery. Copyright © 2015 John Wiley & Sons, Ltd.     

中国银杏种质资源研究进展

作者结合近几年的研究，概述了银杏雌雄株早期鉴定、染色体数目与核型及叶用银杏品种选育等方面的研究进展。     

昆虫性信息素在森林害虫监测和防治中的应用

阐述了昆虫性信息素在森林害虫监测和防治中的应用及应用中存在的问题，并对应用前景进行了展望。     

亚洲型舞毒蛾中国地理种群飞行能力初探

为了探究亚洲型舞毒蛾的飞行能力,以采自河北和内蒙两地的亚洲型舞毒蛾为试验对象,应用昆虫飞行信息系统,分析亚洲型舞毒蛾的最大飞行速度、累计飞行距离和累计飞行时间。结果表明：亚洲型舞毒蛾雌雄个体间飞行能力有显著差异,雄虫比雌虫具有更强的飞行能力,雄虫平均累计飞行距离为6.76 km,雌虫平均累计飞行距离为1.85 km;1日龄成虫已具备较强的飞行能力,在飞行时间、飞行距离上,雌虫随着日龄的增长呈现出明显的线性下降趋势;交配对雄虫的飞行能力无显著影响,雌虫产卵后飞行能力明显下降。     

双温多重PCR鉴定猪早期胚胎性别的研究

摘 要：通过PCR扩增哺乳动物雄性决定基因SRY来鉴定胚胎的性别在畜牧业生产上已经得到广泛应用,优化技术路线,缩短鉴定时间对后期实验的成功有非常重要的意义。本实验根据猪的SRY基因和GAPDH（内标）基因序列,分别设计并合成两对引物,通过双温PCR反应实现对猪早期胚胎性别的快速鉴定,结果表明：母猪只能扩增出 404bp 的GAPDH基因片段,而公猪能同时扩增出309 bp 的 SRY基因片段和 404 bp 的GAPDH基因片段。阳性率为100 %,鉴定时间较常规时间缩短2个小时。表明该检测方法快速、准确。本方法为在转基因克隆动物研究中快速鉴定胎儿成纤维细胞系的性别提供了可靠的技术保证。     

鹌鹑性别鉴定的分子标记方法

采用PCR方法扩增北京白羽蛋用鹌鹑基因组中性别基因CHD相关片段,探讨鹌鹑性别的分子标记方法。通过特异引物2550F/2718R,对3对已知性别和14只未知性别鹌鹑性别基因片段进行特异性扩增。结果表明,这对引物从雄性鹌鹑中扩增出1条片段,从雌性鹌鹑中扩增出2条片段,可以对鹌鹑的性别作出准确鉴定。该方法可以应用于初生鹌鹑的性别筛选,降低饲养成本,提高经济效益。对2条片段进行克隆测序,片段长度分别为613和446bp。     

橘小实蝇遗传性别品系性比与单雌有效卵量的关系

为进一步优化橘小实蝇遗传性别品系大量饲养技术,对其性比与有效卵量的关系进行了研究.结果表明:在一定种群密度下,当性比(♀∶♂)为1∶2、1∶1、2∶1、4∶1时,单雌有效卵量间没有显著差异;对性比(X)和单雄有效卵量(Y)间的关系进行拟合,得到方程Y=0.747X3-36.408X2+887.368X-102.805,由方程可知,在一定种群密度下,1.5∶1♀∶♂2∶1的性比最适宜橘小实蝇遗传性别品系的人工繁育.     

甜菜夜蛾性信息素研究及应用进展

甜菜夜蛾是我国多发的一种蔬菜害虫,化学农药的大量使用造成其抗药性大幅上升,防治效果明显下降。因此,安全有效的生物防治已成为当前的研究热点,其中利用昆虫性信息素进行害虫的测报与防治受到了广泛的关注和重视。现综述甜菜夜蛾性信息素的研究现状、性信息素在测报与防治中的应用以及利用性信息素的优点和局限性。