The response of ectomycorrhizal fungi on Pinus densiflora seedling roots to liquid culture

Japanese red pine (Pinus densiflora) seedlings taken from a nursery were grown in liquid culture with all roots entirely submerged in water. The aims of the present study were to observe the reactions of preformed ectomycorrhizae to liquid culture and to examine new infections by ectomycorrhizal fungi on newly formed root tips in liquid culture. Inoculation levels were controlled by trimming the ectomycorrhizal roots to one of three selected root lengths. The results showed that the mantles of pre-formed ectomycorrhizae were lost during the 8 weeks of the liquid culture and that these preformed root tips became blackish and wrinkled, but Hartig nets remained in these blackish root tips. On the newly formed lateral root tips, no ectomycorrhizal mantles were formed, although Hartig nets were found. In addition, the level of inoculum did not affect the frequency of Hartig nets in newly formed root tips, suggesting that the density of inoculum was more important than the amount of inoculum for new infection. In conclusion, ectomycorrhizal fungi endured and infected new roots while submerged; however, only Hartig nets were formed and not mantles.     

马氏珠母贝转录组数据的重新组装

对本实验室和其他学者已经发表的马氏珠母贝外套膜和珍珠囊的454焦磷酸测序转录组数据以及NCBI中的EST数据进行了重组装、同源序列比对和GO注释分析。重组装获得了30266个contig,平均长度522 bp,其中最长的contig为4144 bp;NR数据库BLAST分析获取了2310个相似性contig(E≤10?5),其中1902个在模式动物(人、小鼠、海胆、线虫、斑马鱼、果蝇或者太平洋牡蛎和珠母贝)中可以查找到同源序列。基因注释(GO)结果表明,注释到生物学过程的3846个contig可分为23个亚类,其中代谢过程蛋白、细胞过程蛋白和生物学调控蛋白为contig数量最多的3个亚类;注释到分子功能的4601个contig共分为11个亚类,其中结合蛋白的contig数量最多,其次是具有催化活性的蛋白和结构分子活性蛋白;注释到细胞成分的2992个contig分为17个亚类,其中细胞和细胞组成部分的contig数量最多,其次分别是细胞器和大分子复合体contig数量。本研究结果有助于开展外套膜和珍珠囊特异性表达基因的大规模筛选。     

短蛸的早期生长特征

对孵化后1~50日龄短蛸(Octopus ocellatus)幼体的体重、全长、腕长及胴长进行测量,观察并分析其早期生长变化特征。在水温为22℃~24℃的养殖条件下,初孵短蛸平均全长为10.03 mm。11日龄幼体开始营底栖生活,以此为分界线划分为浮游期和底栖期。 结果显示,1~11日龄浮游短蛸体重增长为立方函数增长类型,y = 0.0001x3 – 0.0019x2 + 0.0098x + 0.0409;11~50日龄的底栖短蛸体重增长为指数函数增长类型,y = 0.0284e0.092x。在1~50日龄短蛸幼体的生长过程中,体重(g)与全长(mm)呈立方函数关系,y = –8e–07x3 + 0.001x2 – 0.011x + 0.099;全长(mm)与腕长(mm)呈线性关系,y = 1.314x + 4.952;体重、全长及腕长分别与日龄呈立方函数关系,y = 6e–05x3 – 0.003x2 + 0.036x – 0.03、y = 0.0004x3 + 0.002x2 + 0.307x + 10.604、y = 0.0004x3 – 0.007x2 + 0.364x + 4.205。通过研究短蛸幼体的生长发育特征,从而加深了对幼体生长的了解,并为短蛸人工繁育的研究提供参考依据。     

小片与蚌间的关系对珍珠质量的影响

本研究采用褶纹冠蚌同一个体自体外套膜小片育珠,结果珍珠质量明显提高。采用三角帆蚌制取外套膜小片植入褶纹冠蚌。结果珍珠质量极差,大多数蚌产不出珍珠;采用褶纹冠蚌制取外套膜小片植入三角帆蚌,结果三分之一的蚌能得到质量高于褶纹冠蚌,产量高于三角帆蚌的珍珠。作者认为供片蚌和受片蚌间相适关系影响珍珠质量,研究如何提高褶纹冠蚌小片在三角帆蚌体内成珠的比率,在生产上是很有意义的。     

短蛸的早期生长特征

对孵化后1～50日龄短蛸(Octopusocellatus)幼体的体重、全长、腕长及胴长进行测量,观察并分析其早期生长变化特征。在水温为22℃～24℃的养殖条件下,初孵短蛸平均全长为10.03 mm。11日龄幼体开始营底栖生活,以此为分界线划分为浮游期和底栖期。结果显示,1～11日龄浮游短蛸体重增长为立方函数增长类型,y=0.0001x^3–0.0019x^2+0.0098x+0.0409;11～50日龄的底栖短蛸体重增长为指数函数增长类型,y=0.0284e^0.092x。在1～50日龄短蛸幼体的生长过程中,体重(g)与全长(mm)呈立方函数关系,y=–8e–07x^3+0.001x^2–0.011x+0.099;全长(mm)与腕长(mm)呈线性关系,y=1.314x+4.952;体重、全长及腕长分别与日龄呈立方函数关系,y=6e–05x^3–0.003x^2+0.036x–0.03、y=0.0004x^3+0.002x^2+0.307x+10.604、y=0.0004x^3–0.007x^2+0.364x+4.205。通过研究短蛸幼体的生长发育特征,从而加深了对幼体生长的了解,并为短蛸人工繁育的研究提供参考依据。     

Mantle transplantations in freshwater pearl mussels in Thailand

Allograft and xenograft mantle transplantations were studied in three species of freshwater pearl mussels, Hyriopsis (Limnoscapha) myersiana, H. (L.) desowitzi and Chamberlainia hainesiana, by transplanting foreign mantle tissue into the mantle tissue of a host mantle. The pearl sac is completely formed within 15 days after an allograft. After a xenograft from a C. hainesiana donor into a H. (L.) myersiana recipient, it took 13 days, and in the opposite case it took 15 days. For a H. (L.) desowitzi donor, it took 21 days in a C. hainesiana recipient and 27 days in a H. (L.) myersiana recipient. When the recipient was H. (L.) desowitzi, no pearl sac was observed after xenografts from either of the other two mussel species. Allografts of C. hainesiana and H. (L.) myersiana yielded the highest success rate of forming pearl sacs (96 and 97% respectively). Xenografts from a C. hainesiana donor into an H. (L.) myersiana recipient yielded 94%, and the opposite case yielded 90%. The first completed pearl layer was found for xenotransplantation into a C. hainesiana recipient from an H. (L.) myersiana donor at 126 days after transplantation.     

干巴菌外生菌根及菌丝的观察

干巴菌（Ｔｈｅｌｅ－ｐｈｏｒａｇａｎｂａｊｕｎ）是一种外生菌根真菌，主要与云南松（Ｐｉ－ｎｕｓｙｕｎｎａｎｅｎｓｉｓ）形成单轴二叉分枝和单枝的菌根。干巴菌的双校菌丝呈淡黄色和白色两种菌丝，分枝均稀少，菌丝分隔，菌丝具有锁状联合，有“Ｈ”型的菌丝细胞接合现象。     

Ectomycorrhizal impacts on nutrient uptake pathways in woody roots

Ectomycorrhizae are a common symbiosis between the roots of woody plants and fungi common to the soil. That ectomycorrhizae can assist the plant partner in absorbing mineral nutrients has long been established. However, the impact of mycorrhizae on pathways available for soil nutrients to enter the root system is not clear. In particular, the impact of the fungal mantle, which surrounds the root tips, is most critical. In the present study, we assessed the permeability of the Pinus banksiana/Hebeloma cylindrosporum fungal mantle to both berberine and radioactive sulfate ions. It was found that the fungal mantle was completely impermeable to tracer dye. To test the permeability to sulfate ions, a novel technique called the internal perfusion technique was employed. By this method, permeability can be assessed. The fungal mantle proved to be impermeable to sulfate over a 24-hour exposure period. Based on recent findings pertaining to root anatomy, this result suggests that the plant may be highly dependent on the fungus to supply mineral nutrients as there is little plant tissue capable of nutrient absorption outside the fungal mantle.     

体外培养菲律宾蛤仔外套膜细胞的增殖

以D-MEM和M199为基础培养基,对菲律宾蛤仔的外套膜进行了细胞培养,并以RNA/DNA比值作为评价细胞增殖的指标.结果表明:外套膜细胞增殖的主要形式是从组织块中迁出,培养前期细胞分泌旺盛,细胞在体外生长可达15 d;外套膜细胞在D-MEM中的生长优于M199;RNA/DNA指标与直观观察的细胞生长状况相吻合,利用这一指标,有助于客观评价体外培养菲律宾蛤仔细胞的增殖特性.     

番红砗磲外套膜颜色多态性及其与生长性状相关性研究

本研究以南海西沙海域番红砗磲(Tridacna crocea)为实验对象,通过CSE-1成像色度检测分析系统和聚类分析方法研究其外套膜颜色多态性,同时,比较外套膜颜色与形态性状的相关性。结果显示,大部分番红砗磲外套膜颜色分布在蓝原色和红原色区域,少部分个体分布在绿原色区域,且偏亮绿色;番红砗磲外套膜颜色共聚为6个颜色类群,各类群间颜色色差均>15,其中,第4类深蓝色和第6类黄色色差最大,为74.68;第3类浅蓝色和第4类深蓝色色差最小,为18.98;番红砗磲外套膜颜色L、a、b值与壳高呈显著正相关(P<0.05),相关系数分别为0.2080、0.2210和0.2375。本研究结果可为砗磲资源保护和珊瑚礁生态系统恢复提供参考。