Genetic Diversity of Radish (Raphanus sativus L.) Germplasm Resources Revealed by AFLP and RAPD Markers

Genetic diversity of 56 radish accessions, representing nearly all the typical types and origins of cultivated radish germplasms conserved in the National Mid-term Genebank for Vegetables of China, was assessed with amplified fragment length polymorphism (AFLP) and random amplified polymorphic DNA (RAPD) markers. A total of 72 and 128 polymorphic bands were generated by the 12 selected RAPD primers and eight AFLP primer combinations respectively. A moderate correlation with the value of r = 0.66 was observed between AFLP and RAPD markers. The total 200 polymorphic bands were integrated to assess the genetic diversity of 56 radish accessions. The Jaccard similarity coefficients between the accessions varied from 0.30 to 0.83 with the mean of 0.54. Cluster analysis classified the germplasms into three groups of var. hortensis Becker, var. sativus, and var. niger Kerner. The three-dimensions scatter plot of principle coordinate analysis (PCA) further divided var. hortensis Becker germplasms into two separate groups. The results indicated that the genetic diversity harbored among var. hortensis Becker germplasms was very abundant, which could be further exploited for radish genetic improvement.     

Effects of low night temperature on pigments,chl <Emphasis Type="Italic">a</Emphasis> fluorescence and energy allocation in two bitter gourd (<Emphasis Type="Italic">Momordica charantia</Emphasis> L.) genotypes

Using two different inbred lines of Momordica charantia (bitter gourd), Y-106-5 and Z-1-4, the cell membrane stability, leaf water potential, pigment contents and the chlorophyll a fluorescence were investigated with different low night temperature (LNT) treatments over a 7 day time period and the sequent a 7 day recovery. Under LNT treatments, electrolyte leakage increased in both inbred lines and it increased more significantly in Y-106-5 plants than that in Z-1-4. The content of Chl b and total Chl decreased, while the Chl a/b ratio increased in stressed plants of the two lines. Almost all LNT treatments induced little change in Chl a content in Z-1-4 whereas obvious decreases in 5 and 8°C treated Y-106-5 plants were observed. Chilling changed the water status of plants and induced decreases of leaf water potential (LWP) in 5 and 8°C treated plants. LNT treatments also resulted in changes in the chlorophyll fluorescence parameters in bitter gourd leaves. The potential PSII activity (F _v/F _o) was reduced obviously by LNT stress and showed more sensitive to LNT than the maximum quantum efficiency of PSII primary photochemistry (F _v/F _m). The efficiency of open PSII centers exhibited a slight decrease whereas the photochemical quenching efficient (q _P) was affected more seriously by LNT stress in both two inbred lines. The allocation of energy was rearranged by LNT stress. The light fraction used for PSII photochemistry (P) was reduced, while that used for heat dissipation (D) and the third fraction of absorbed light defines excess energy (E) increased due to the chilling stress. The impacts of LNT stress on bitter gourd generally increased with the number of LNT chilling and the severe night chilling. Plants were little affected by 12°C night chilling and the most acute damage was found in 5°C night chilling treatments. A 7 day recovery mitigated the adverse effects of LNT for both lines and almost all LNT treated plants restored to control levels except 5°C night chilling treated Y-106-5 plants. The two lines have a variance in tolerance to LNT stress and display obvious differences of phenotypes under extreme conditions.     

西藏北部地区蝠蛾属二新种记述（鳞翅目：蝙幅蛾科）

本文报道了西藏北部地区分布的幅蛾属２新种──巴吉蝠蛾Ｈｅｐｉａｌｕｓｂａｑｉｎｇｅｎｓｉｓ,ｓｐ．ｎｏｖ．及当雄幅蛾Ｈｅｐｉａｌｕｓｄａｍｘｕｎｇｅｎｓｉｓ,ｓｐ．ｎｏｖ．模式标本存中国科学院昆明动物研究所。     

Meningeal lymphatics regulate radiotherapy efficacy through modulating anti-tumor immunity

As a first-line treatment, radiotherapy (RT) is known to modulate the immune microenvironment of glioma, but it is unknown whether the meningeal lymphatic vessel (MLV)-cervical lymph node (CLN) network regulates the process or influences RT efficacy. Here, we show that the MLV-CLN network contributes to RT efficacy in brain tumors and mediates the RT-modulated anti-tumor immunity that is enhanced by vascular endothelial growth factor C (VEGF-C). Meningeal lymphatic dysfunction impaired tumor-derived dendritic cell (DC) trafficking and CD8⁺ T cell activation after RT, whereas tumors overexpressing VEGF-C with meningeal lymphatic expansion were highly sensitive to RT. Mechanistically, VEGF-C-driven modulation of RT-triggered anti-tumor immunity was attributed to C-C Motif Chemokine Ligand 21 (CCL21)-dependent DC trafficking and CD8⁺ T cell activation. Notably, delivery of VEGF-C mRNA significantly enhanced RT efficacy and anti-tumor immunity in brain tumors. These findings suggest an essential role of the MLV-CLN network in RT-triggered anti-tumor immunity, and highlight the potential of VEGF-C mRNA for brain tumor therapy.Subject terms: Tumour immunology, Radiotherapy     

东北次生杨桦林土壤碳氮动态特征

土壤分级组分是研究其碳氮动态的基础,次生杨桦林作为东北地区主要的天然林类型,目前相关数据的欠缺状态要求对此进行深入研究。为此,采集0—10cm、10—20cm、20—30cm长白山次生杨桦林土壤,通过土壤颗粒组分物理化学分级方法,将土壤分成5种组分:沙和稳定团聚体土壤组分(SA)、酸不溶土壤组分(AI)、易氧化土壤组分(EO)、颗粒态土壤组分(P)和可溶性土壤组分(S),进而分析了不同组分的质量分数、碳氮含量、碳氮分配比例及红外光谱5类官能团相对含量,旨在探讨次生杨桦林土壤固碳、氮供应机制。结果显示,接近90%的土壤质量集中在稳定组分AI(66.21%)和SA(22.11%)上,导致稳定组分中碳截获量最大(占土壤总碳量的2/3),而且其C/N比活跃组分(P和EO)大2—9倍;与碳不同,由于活跃组分中N含量比稳定组分大4—80倍,致使活跃组分P和EO氮的分配比例最大,分别占土壤总氮的33.1%和26.0%;除了占土壤质量很少的P和S外,组分间以及组分内的碳氮间多具有显著相关关系。这种土壤碳、氮在不同组分间贮存方式的差异使得土壤碳储存稳定性更高、而N肥力供应更快速。伴随不同组分碳氮储存的变化,不同组分间红外官能团存在显著差异,AI组分中绝大多数官能团相对含量均最低,而P和S组分中绝大多数官能团相对含量均较高,绝大多数官能团相对含量与碳含量、氮含量呈现显著的正相关关系,反映了官能团具有维持土壤碳氮的功能。同时,官能团与土壤C/N具有显著相关关系,反映出组分官能团相对含量的高低具有指示组分化学活性高低的作用。研究发现对于林分土壤的碳截获与氮供应的机制阐明具有重要的科学意义,这为深入了解东北次生杨桦林碳氮动态及对未来气候的响应提供基础数据。     

蟹爪叶盾蕨石油醚提取物的成分分析及抗菌活性研究

为了研究蟹爪叶盾蕨(Neolepisorus ovatus(Bedd.)Ching f. doryopteris(Christ)Ching)石油醚提取物的化学组成及抗菌活性,采用气相色谱-质谱法分析蟹爪叶盾蕨石油醚提取物的成分,采用琼脂平板打孔法检测提取物对大肠杆菌、金黄色葡萄球菌、藤黄八叠球菌的抑制活性。从蟹爪叶盾蕨石油醚提取物中鉴定出38种化学成分,占出峰总数的92. 76%,其中豆甾-4-烯-3-酮(19. 83%)、何帕烯(16. 40%)、β-香树脂酮(14. 93%)等甾体和萜类化合物含量丰富。抑菌活性结果显示,蟹爪叶盾蕨石油醚提取物对藤黄八叠球菌的抑菌圈为(7. 78±0. 55)cm,对大肠杆菌、金黄色葡萄球菌、白色念珠菌没有抑制作用。所鉴定的化合物均首次从蟹爪叶盾蕨检测到,蟹爪叶盾蕨石油醚提取物对藤黄八叠球菌有抑制作用。此研究结果为该植物的开发利用提供了科学依据。     

微生物太阳能燃料电池的研究进展

摘要:能源危机已经成为阻碍世界发展的主要问题之一,微生物燃料电池的出现为能源危机提供了新的解决途径。将植物和微藻等光合生物与微生物燃料电池整合为微生物太阳能燃料电池(MSCs),能够实现将太阳能转化为电能。微生物太阳能燃料电池不仅能够实现电能持续稳定的产生,而且在污水处理,生物柴油加工以及中间代谢物生产等方面具有广阔的应用前景。本文从光合生物在微生物燃料电池中的作用的角度出发,在参考大量文献的基础上对微生物太阳能电池进行较为全面的综述,并评述其中的优点及不足之处,最后对微生物燃料电池面临的挑战及研究需求做简要分析。旨在为未来微生物太阳能燃料电池的实际应用提供参考。     

内蒙古野生葱属植物资源的开发利用与保护

内蒙古葱属植物分布较广、种类繁多,这类植物对人类有较高的利用价值.多年来人们对这类植物不合理的采集利用,导致了资源及相关植被的破坏.通过我们近几年的调查研究.找出了用种子繁殖扩大种植面积和合理利用的有效措施.既扩大了野生葱属植物的利用空间,又对野生葱属资源和天然植被起到了很好的保护作用.