Effect of salinity on the growth, and agar yield and composition of Gracilaria tenuistipitata var liui Zhang et Xia

Gracilaria tenuistipitata varliui Zhang et Xia is cultivated at two different salinities (21, 33) in the laboratory for 4 weeks. The daily growth rate is determined. The total agar yield and fractional agar composition are analyzed. Results show that algae grow faster in low salinity. The total agar yield is higher under high salinity conditions than under low salinity conditions. Among the eight fractions extracted, the yields of cold water extract and 40% ethanol extract are about the highest. In low salinities the yields of autoclaved extract and 60% ethanol extract are higher, while the yield of cold water extract is lower relative to high salinities.

(Prunussalicina)WRKY 33的克隆与表达分析

WRKY类转录因子是植物防御反应信号转导的重要组成部分,本研究为了探讨WRKY33基因的功能,以嫩叶为材料,采用RT-PCR和RACE技术相结合的方法,克隆得到WRKY33全长c DNA(命名为Ps WRKY33),对其进行生物信息学分析。以基因组DNA为模板,对该基因的ORF区域进行PCR扩增,获得WRKY33的g DNA全长。采用荧光定量PCR技术检测该基因在水杨酸处理下的表达模式。试验结果表明:Ps WRKY33 c DNA全长为2 113 bp,开放阅读框长为1 770 bp,编码589个氨基酸;Ps WRKY33蛋白含有两个WRKY保守结构域,与Pm WRKY33蛋白同源性最高。Ps WRKY33基因组全长为2 844 bp,存在3个内含子和4个外显子。荧光定量结果表明:Ps WRKY33在1 mmol/L水杨酸处理后,30 h表达量最高,呈先上升后下降的趋势。研究结果为深入研究WRKY33基因与水杨酸诱导植物抗病性的关系提供一定的参考价值。