Artificial inoculation of banana tissue culture plantlets with indigenous endophytes originally derived from native banana plants

Fusarium wilt disease of banana is one of the most harmful fungal diseases affecting banana production worldwide. We hypothetically proposed that the loss of indigenous endophytes in tissue culture propagation of banana might be related to increased disease severity on banana plants. In the present study, a mixture of uncultivated endophytes, which was originally derived from native healthy banana plant in plantation, was used to artificially inoculate banana tissue culture plantlets. A broad spectrum of bacterial communities was detected in the roots of artificially inoculated plantlets by 16S ribosomal RNA gene analysis, and γ-Proteobacteria was identified as the dominant group. Banana wilt pathogen Fusarium oxysporum f. sp. cubense race 4 was inoculated to the plantlets after potting to investigate disease progress. With early diagnosis of fungal pathogen infection, 54% reduction was detected in artificially inoculated plantlets compared to endophyte-free control plantlets. The re-introduction of naturally-occurring endophytes into tissue culture banana plantlets led to a 67% suppression rate of wilt disease at the fifth month after pathogen infection on plantlets in the greenhouse. In addition to disease suppression, growth of host plantlets was also promoted with the inoculation of endophytes. The artificial inoculation method provided a foundational understanding of ecological enrichment to control banana wilt disease in future.     

基因枪在大鼠闭塞性血管病基因治疗中的应用

探讨利用基因枪技术转移肝细胞生长因子基因治疗大鼠肢体闭塞性血管病的可行性,构建了携带人肝细胞生长因子（HGF）基因的重组真核表达载体（pUDKH),在制备好大鼠下肢闭塞性血管病模型后,通过基因枪或肌肉直接注射法,向局部缺血部位肌肉中转移pUDKH,每只5ug(基因枪）和12ug(肌肉注射）,应用常规组织病理切片（H．E．染色）及免疫组织化学方法观察血管形成及基因表达,转移pUDKH后第10天,用基因枪和直接注射法转移的局部肌肉组织的HGF的表达明显高于转移空白质粒（pUDK)的对照组,pUDKH组可见明显的小血管新生,而pUKD组至20天时仍未观察到或仅见到极少量的新生血管,基因枪与肌肉注射两组相比血管密度无明显差异,采用基因枪直接转移pUDKH裸露质粒子肢体缺血局部的方法是可行的,转移的基因可在局部有效表达,达到促进血管形成的预期目的。     

京津冀风沙源区沙化土地治理关键技术研究与示范

京津冀风沙源区是我国北方生态屏障的重要组成部分。面向我国北方风沙区沙化土地综合治理、典型脆弱生态修复与保护等重大科技需求,京津冀风沙源区沙化土地治理关键技术研究与示范项目将综合运用长期定位观测、控制实验、多源遥感数据融合、技术示范等方法,重点研究京津冀风沙源区土地沙化形成机制与生态修复机理,研发一批沙化土地治理与产业化关键技术,并在各治理区开展试验示范,集成京津冀风沙源区沙化土地治理与产业化技术体系,构建沙化土地综合整治空间决策支持系统,为京津风沙源治理工程建设、保障京津冀地区生态安全及满足2022年北京冬奥会生态需求提供科技支撑。     

The Analysis of Homegarden Plant Diversity at the Mongolian Household Level in Horqin Sandy Land——A Case Study in Horqin Left Wing Real Banner of Inner Mongolia

In order to show the function of agricultural protection of biodiversity at the level of homegarden, comparative analysis was operated between 20 farmer households through random sampling and farmers recommended in Horqin Left Wing Real Banner Tongliao city Inner Mongolia Autonomous Region and 10 farmer households of the Han nationality in the neighborhood. Thirty sampling plots of homegardens are investigated. The result indicates there are 100 homegarden plants in Bashou village, 84 in Hariwusu livestock farm, and 87 in Gongjihao village. It involves the cultivated and wild vegetables, fruits, and plants used for ornamental, medicine and forage. The comparative analysis of species richness demonstrates, among these villages the species richness of Bashou village is highest, while Hariwusu livestock farm is lowest. The former village contributes greatly to the conservation of plant biodiversity. These differences result from their respectively different natural conditions, homegarden areas, homegarden history, homegarden management conditions, traditional knowledge and culture understanding of homegarden manager, local farmers and herdsmen on homegarden plants.The homegarden plants from the three investigated villages are cataloged preliminary in the end of the paper.     

The role of mast cells and macrophages in amiodarone induced pulmonary fibrosis and the possible attenuating role of atorvastatin

Amiodarone (AM) is an effective anti-arrhythmic drug. We investigated the role of mast cells and macrophages on AM induced pulmonary fibrosis and the action of atorvastatin on this fibrosis. Rats were allocated into four groups; negative control (1), positive control (2), 30 mg/kg body weight/day AM (3) and AM + 10 mg/kg/day atorvastatin (4). Lungs were harvested and prepared for histology and immunohistochemistry. Hematoxylin and eosin stained sections of group 3 exhibited disorganized lung architecture. We found cellular debris in the lumen of both intrapulmonary bronchi and bronchioles with partial disruption of the thickened epithelial lining and mononuclear cellular infiltration into the lamina propria. We also observed thickening of the epithelial lining and the smooth muscle layer. Congested, dilated and thickened blood capillaries and thickened inter-alveolar septa were observed with mononuclear cellular infiltrates in the lung of group 3. Most alveoli were collapsed, but some dilated ones were detected. In some alveoli, type ?? pneumocytes were increased, while type I cells were decreased. We observed significant increases in the amount of collagen in the thickened inter-alveolar septa, around bronchioles and around blood capillaries in sections from group 3. We found a significant increase in mast cells and alveolar macrophages in group 3 compared to group 1. Mast cells and macrophages appear to play important roles in AM induced pulmonary fibrosis. Atorvastatin appears to attenuate this condition.     

Study on Traditional Knowledge of Wild Edible Plants Used by the Mongolians in Xilingol Typical Steppe Area*

The local herdsmen were served as informants, methods of interviews and voucher specimen collection and identification have been used to conduct ethnobotanical field investigations on wild edible plants in the Xilingol typical steppe area, Inner Mongolia. The results show that 29 species and two varieties of wild plants used for food and drinks by the Mongolians in Xilingol typical steppe area. The edible parts of the plants are whole plant, aerial parts, roots, stems, bulbs, leaves, flowers, fruits or/and seeds respectively. Among them, the leaf is the most widely used part. Six categories of food uses based on the mode of folk edible use were established to classify wild food plants, including wild grain, vegetables, fruit, substitute for tea, seasoning, and snacks. Among them, vegetables were the largest group, followed by plants used as substitute for tea, and plants used for seasoning. Wild plants are usually eaten raw or cooked by the local people. Raw materials and prepared food from wild plants are preserved through the method of pickling and drying. A distinguishing feature of region and ethnic group is that mutton, beef, fresh milk and yoghourt are necessarily used in cooking dish and making milk tea from wild plants by local Mongolians.     

电离辐射对蛋白质分子作用的量子孤波分析

本文运用量子力学方法对蛋白质分子中孤波传播的非线性动力学特征进行了探讨。研究表明：电离辐射产生的自由基对蛋白质分子的伤害将会对携带能量、信息的孤立子波传播产生较为显著的影响。     

大豆疫霉菌的EMS化学诱变

以甲基磺酸乙酯(ethylmethane sulfonate,EMS)为诱变剂,通过其对大豆疫霉菌Phytophthora sojae休止孢萌发的影响,确定化学诱变条件。通过收集单卵孢子,建立了包含640个单卵孢子系的突变体库,其中约有50%的诱变菌系在培养性状和菌落形态方面发生了明显变化,菌落形态多样,表现出较紧密或松散,近圆形或不规则;气生菌丝减少,生长速度较慢或快;在卵孢子产量方面,8.13%的菌系有增加,20.41%的菌系减少,27.82%的菌系极少或者没有卵孢子产生,43.64%的菌系卵孢子产量类似野生型。以质膜氢离子泵蛋白基因PsPMA1(plasma membrane H+-ATPase1)为对象,通过TILLING技术,从320个大豆疫霉菌突变体中获得9个突变体,进一步确认了EMS对大豆疫霉菌的诱变效果,并且估算EMS对大豆疫霉菌的诱变频率至多每115kb发生一个核苷酸变异。新构建的突变体库为开展大豆疫霉病菌的功能基因组研究奠定了遗传材料基础。     

An RXLR effector PlAvh142 from Peronophythora litchii triggers plant cell death and contributes to virulence

Litchi downy blight, caused by the phytopathogenic oomycete Peronophythora litchii, results in tremendous economic loss in litchi production every year. To successfully colonize the host cell, Phytophthora species secret hundreds of RXLR effectors that interfere with plant immunity and facilitate the infection process. Previous work has already predicted 245 candidate RXLR effector-encoding genes in P. litchii, 212 of which have been cloned and tested for plant cell death-inducing activity in this study. We found three such RXLR effectors could trigger plant cell death through transient expression in Nicotiana benthamiana. Further experiments demonstrated that PlAvh142 could induce cell death and immune responses in several plants. We also found that PlAvh142 localized in both the cytoplasm and nucleus of plant cells. The cytoplasmic localization was critical for its cell death-inducing activity. Moreover, deletion either of the two internal repeats in PlAvh142 abolished the cell death-inducing activity. Virus-induced gene silencing assays showed that cell death triggered by PlAvh142 was dependent on the plant transduction components RAR1 (require for Mla12 resistance), SGT1 (suppressor of the G2 allele of skp1) and HSP90 (heat shock protein 90). Finally, knockout of PlAvh142 resulted in significantly attenuated P. litchii virulence on litchi plants, whereas the PlAvh142-overexpressed mutants were more aggressive. These data indicated that PlAvh142 could be recognized in plant cytoplasm and is an important virulence RXLR effector of P. litchii.