野生北五味子生物学特性的研究

采用多年全面调查及三年时间定位,定株观测相结合的方法,对野生北五味子生物学特性进行了深入研究。对其开花结实规律;雌雄同株,异株问题,座果率;物候期;种源与质量关系方面均有新发现。     

Analysis of novel angiotensin-I-converting enzyme inhibitory peptides from protease-hydrolyzed marine shrimp Acetes chinensis.

Acetes chinensis is an underutilized shrimp species thriving in the Bo Hai Gulf of China. In a previous study, we had used the protease from Bacillus sp. SM98011 to digest this kind of shrimp and found that the oligopeptide-enriched hydrolysate possessed antioxidant activity and high angiotensin I-converting enzyme (ACE) inhibitory activity with an IC50 value of 0.97 mg/ml. In this paper, by ultrafiltration, gel permeation chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC), five peptides with high ACE inhibitory activity were purified from the shrimp hydrolysates and their sequences were identified by amino acid composition analysis and molecular weight (MW) analysis. Three of them, FCVLRP (a), IFVPAF (f) and KPPETV (j), were novel ACE inhibitory peptides. Their IC50 values were 12.3 microM, 3.4 microM and 24.1 microM, respectively, and their recoveries were 30 mg/100 g (solid basis of shrimp), 19 mg/100 g and 33 mg/100 g, respectively. Lineweaver-Burk plots for the three novel peptides showed that they are all competitive inhibitors. To test the ACE inhibitory activity of peptide a, f, j after they were digested by digestive enzymes in vivo, 12 derived peptides from FCVLRP and IFVPAF were synthesized based on their amino acid sequences and the cleavage sites of digestive enzymes. No digestive enzyme cleavage site was found in KPPETV. The IC50 values of the derived peptides were determined and the result showed that except for VPAF, FC and FCVL, the ACE inhibitory activity of the other nine derived peptides did not significantly change when compared with their original peptides. Surprisingly, five peptides had lower IC50 values than their original peptides, particularly for RP (IC50 value = 0.39 microM), which is about 30 times lower than its original peptide and almost the lowest IC50 value for ACE inhibitory peptides reported. Therefore, the novel peptides identified from A. chinensis hydrolysates probably still maintain a high ACE inhibitory activity even if they are digested in vivo. This is the first report about novel ACE inhibitory peptides from hydrolysates of marine shrimp A. chinensis. The novel peptides from hydrolysate of A. chinensis and some of their derived peptides with high ACE inhibitory activity probably have potential in the treatment of hypertension or in clinical nutrition.     

Development of a positive preference–performance relationship in an oligophagous beetle: adaptive learning?

The relationship between oviposition preference and larval performance is a central topic in insect–plant biology. In this study, we investigate whether the oligophagous flea beetle, Altica fragariae Nakane (Coleoptera: Chrysomelidae), exhibits a positive preference–performance relationship, and whether oviposition preference develops over time. We tested the beetles using four sympatric plant species: Duchesnea indica (Andrews) Focke (the normal host plant), Agrimonia pilosa Ledeb. (a secondary host plant), and Potentilla chinensis Ser. and Sanguisorba officinalis L. (host plants of two related Altica species) (all Rosaceae). In no‐choice experiments, both oviposition rate and offspring fitness parameters (eclosion rate, development time, and body mass) were highest on D. indica. Oviposition rate was much lower on P. chinensis than on A. pilosa, whereas offspring fitness parameters did not differ significantly between these two host plants. Offspring fitness were lowest for S. officinalis, and adult females refused to oviposit on this acceptable non‐host in a no‐choice situation. Repeated two‐choice experiments showed that the proportion of oviposition on one of the novel host plants decreased significantly over time when the alternative host plant was D. indica. In repeated two‐choice experiments using A. pilosa and P. chinensis, females mainly fed on A. pilosa but distributed their eggs equally over the two host plants, in accordance with the lack of difference in offspring fitness on those hosts. Together, these results showed that A. fragariae females develop a positive preference–performance relationship over time. We suggest that A. fragariae achieves this through adaptive learning of oviposition preference: not only does the female learn to discriminate among the host plants when there is a fitness difference for her offspring, but the female also fails to discriminate when there is no fitness difference.     

Low mtDNA variation and shallow population structure of the Chinese pomfret Pampus chinensis along the China coast

In the present study, population genetic structure and genetic diversity of the Chinese pomfret Pampus chinensis, along the China coast were investigated and compared with that from Indonesia using mitochondrial DNA cytochrome b gene sequences. A total of 28 variable sites (including 18 singleton sites and 10 parsimony information sites) were observed and 23 haplotypes were defined in 330 individuals from 11 localities. The haplotype diversity (H_D) of the populations ranged from 0·540 to 0·828, the nucleotide diversity (π) ranged from 0·081 to 0·295%. Pairwise F_ST statistics showed that significant genetic divergence occurred among populations from different geographical regions. The high dispersal capabilities, geographic segregation and ocean currents may be responsible for the present population genetic structure in this species. In addition, a population expansion event during the late Pleistocene period was inferred. The time of population expansion was estimated to occur about 117 000–169 000 years ago.     

野生中华猕猴桃开花期与海拔高度的关系

报道了江西省武宁县幕阜山地区野生中华猕猴桃开花期与其海拔高度的关系。其开花期随海拔高度增加而延迟。海拔高度每升高１００ｍ,开花期约延迟３ｄ。讨论了这种现象的原因及其在引种驯化工作中的意义。     

四川省都江堰龙池地区苔藓植物染色体的研究

报道了四川省都江堰市龙池地区６种苔藓植物配子体的以体研究结果,５种材料均取其生长点或茎尖,观察和计数了细胞有丝分裂中期的染色体数,１．中华扁萼苔（Ｒａｄｕｌｌａｃｈｉｎｅｎｓｉｓ Ｓｔｅｐｈ．ｖａｒ．ｒｏｐｔｕｄｉｓｔｉｐａ）ｎ＝８;２．蛇苔（Ｃｏｎｏｃｅｐｈａｌｕｍ ｃｏｎｉｃｕｍ（Ｌ．）Ｄｕｎ．）＝９;３．长齿匍灯藓（Ｐｌａｇｉｏｍｎｉｕｍ ｄｒｕｍｍｏｎｄｉｉ （Ｂｒｕｃｈ．＆ Ｓｃｈｉｍｐ     

A New Genus and Species—Cycadostrobilus paleozoicus Zhu of Cycadaceae from the Permian of China

This paper describes a new microstrobilus of palaeozoic Cycadaceae collected from the upper part of Lower Shihezi Formation, Dongshan Mine, Taiyuan, Shanxi, China and named it as Cycadostrobilus paleozoicus Zhu, gen. et sp. nov. This new cycad is the oldest microstrobilus to our knowlege of cycads. In the same locality and layer, there are Primocycas chinensis Zhu et Du, Sphenophyllum emarginatum Brongn. , S. costae Sterz. , S. verticallatum (Schloth.) Brongn. , S. oblongifolium (Germ. et Kaulf. ) Ung. , Tingia carbonica (Schenk.) Halle, T. hamaguchii Kon’no, Macrostachys huttoniformis Halle, Sphenopteris norinii Halle, S. firmata Sze, S. gothanii Halle, Sphenopteridium pseudogermanicum (Halle) Gu et Zhi, Pecopteris feminaeformis (Schloth.) Sterz. , P. wongii Halle, P. tuberculata Halle, P. unita Brongn. , P. taiyuanensis Halle, Emplectopteris triangularis Halle, Taeniopteris norinii Halle, T. spp. , Cordaites principalis (Germ.) Gein. , Cornucarpus patulus Halle, Radicites spp. and a few taxa unknown to palaeobotanical data. The authors consider that Cycadostrobilus paleozoicus is the same species as Primocycas chinensis, and its veg.etative leaves are similar to those of the genus Taeniopteris, e.g.T. norinii Halle.     

石竹一新变种

本文发表石竹一新变种:三脉石竹 Dianthus chinensis L. var.trinervis D.Q.Lu。     

中国蛤蜊神经系统显微结构的初步研究

中国蛤蜊中枢神经包括一对脑神经节,一对足神经节和一对脏神经节,各神经节均由神经节被膜,胞体区和中央纤维网三部分组成,脏神经节较腹足类的要复杂,分区现象较明显,脑和足神经节相对较简单,无明显分区和分层现象,神经元胞体可分为大（４０～５４μｍ）,中（２５～４０μｍ）,小（６～２０μｍ）三种类型。