京西稻的百年传承与发展

京西稻是清康熙、雍正、乾隆等亲自选育的优良品种,在与紫禁城并重的“三山五园”政治中心内外种植,具有多重价值属性,属于皇家御稻。从2000年起,基于北京水资源匮乏等原因,京西稻种植面积大幅度降至134 hm²左右,处于濒危状态。在保护传承过程中,京西稻入选中国重要农业文化遗产目录。在新修订的《北京历史文化名城保护条例》中,又将京西稻列入遗产保护目录。在海淀区,京西稻已经深入公园、学校、社区、酒店等地,在教育文化中发挥着农业以外的作用。     

Preliminary assessment of large‐scale co‐culture of sandfish (Holothuria scabra) with the Babylon snail (Babylonia areolata) in earthen ponds and in raceways

Holothuria scabra (sandfish) and Babylonia areolata were trialed in two large‐scale co‐culture experiments. Experiment 1 assessed co‐culture in 4 × 400 m² earthen ponds where Babylonia were cultured in a central pen at a density of 400 individuals/m² with sandfish occupying the remaining pond space at 1.1 individuals/m². Sandfish grew from 18.20 ± 6.67 g to 119.03 ± 17.74 g in 92 days and Babylonia (fed trash fish in both experiments) grew from 0.90 ± 0.38 g to 4.93 ± 1.44 g, but Babylonia growth was not increased in co‐culture compared to monoculture. Water and sediment quality varied between co‐culture and monoculture ponds. Neither showed clear improvement due to sandfish culture. Experiment 2 compared non‐segregated sandfish‐Babylonia co‐culture with Babylonia monoculture in 20 m² concrete raceways. Sandfish were cultured at 2 individuals/m² and Babylonia at 300 individuals/m². Sandfish grew up to 1.91 g.day^?1 with 100% survival. Babylonia weight gain was significantly greater in co‐culture raceways (3.35 ± 0.64 g over 61 days), which was double that of Babylonia in monoculture. Substrate total N was reduced by 20% in co‐culture compared with monoculture (p = .032). This provisional study of commercial scale sandfish‐Babylonia co‐culture demonstrates culture compatibility, providing a basis for further system development.     

养殖模式对草鱼池塘底泥微生物群落结构影响的分析

为了解养殖模式对主养草鱼(Ctenopharyngodon idellus)池塘底泥微生物群落结构的影响,使用高通量测序方法分析了山塘、精养和鱼菜共生三种模式下草鱼池塘底泥微生物的结构特征。结果显示:(1)精养池塘水体COD_Mn、总氮(TN)和总磷(TP)[(35.67~108.34)mg/L、(3.40~7.93)mg/L、(1.35~2.19)mg/L]显著高于山塘[(2.67~24.33)mg/L、(0.77~3.30)mg/L、(0.38~0.77)mg/L]和鱼菜共生池塘[(31.67~58.50)mg/L、(2.40~3.43)mg/L、(0.81~1.22)mg/L],且养殖后期呈上升趋势,山塘和鱼菜共生池塘后期呈下降趋势。(2)三种模式条件下底泥微生物群落结构存在显著差异,但鱼菜共生与精养池塘底泥菌群结构相似性高于山塘模式;山塘池塘底泥微生物丰富度显著低于鱼菜共生和精养池塘,但多样性无显著性差异;山塘菌群多样性指数与环境因子无相关性,但精养模式ACE指数与TN、NH⁺₄、TP、DO呈显著负相关,Shannon指数与TN和DO呈显著负相关;鱼菜共生模式ACE指数与NH⁺₄、TP、COD_Mn呈显著正相关,Shannon指数与NH⁺₄、TP、DO呈显著正相关。(3)山塘池塘核心菌群四季变化差异大;鱼菜共生和精养池塘核心菌群四季均以地杆菌属(Geobacter)、厌氧粘细菌属(Anaeromyxobacter)和脱氯单胞菌属(Dechloromonas)等厌氧和兼性厌氧菌为主。结果表明,鱼菜共生模式底泥微生物群落受环境因子影响小,能够达到控制水体COD_Mn和TN的目的。     

公共数字文化服务人才建设问题浅析

公共数字文化服务是公共文化服务与数字信息技术相结合的产物,是公共文化服务体系中的重要组成部分。人才建设问题是完善公共数字文化服务体系的关键保障性因素。文章拟结合中国公共数字文化服务人才建设现状及问题,分析相关成因,探讨提出如多渠道培训方式、用户满意度测试等人才培养措施,以完善公共数字文化服务体系。     

Retrospect on in vitro androgenesis of sorghum (Sorghum bicolor)

Development of sorghum hybrids can immensely benefit from an enhanced anther culture protocol since the resultant doubled haploids would accelerate, as in other major cereal crops, the attainment of homozygosity and fixation of alleles. Production of the hybrids that have got high yielding, stress tolerance and other traits of industrial significance in a shorter time as compared to the current trend can hence be realized. This review presents the advances that have been made in the development of such a protocol, with closer attention to androgenic induction components of pre-treatment, culture media composition and conditions as well as ploidy determination and eventual chromosome doubling. From the findings of this review, it is clear that further work is desired to ensure a protocol, that to a large degree, breaks the genotype dependency trend that has been widely cited to impede the usability of the tested protocols.     

不同浓度NAA/6BA配比对不同品种甘薯茎尖培养特性的影响

为明确不同品种甘薯茎尖培养的最佳NAA/6BA配比,设置0.1 mg/L/2.5 mg/L、0.2 mg/L/2.5 mg/L、0.2 mg/L/1.0 mg/L 3组NAA/6BA浓度配比处理,观测不同浓度激素处理对‘北京553’、‘红香蕉’、‘苏薯8号’、‘烟薯25’、‘安吉芋’、‘济徐23’、‘渝紫7号’、‘商薯19’茎尖培养成苗率、愈伤组织直径、不定根数目、叶片数和植株高度的影响,同时调查不同品种试管苗的移栽成活率。结果表明,‘红香蕉’、‘济徐23’、‘渝紫7号’、‘商薯19’在0.1 mg/L/2.5 mg/L的处理下培养效率最高;‘安吉芋’在0.2 mg/L/2.5 mg/L的处理下培养效率最高;‘苏薯8号’、‘北京553’、‘烟薯25’在0.2 mg/L/1.0 mg/L的处理下培养效率最高。因此,在甘薯茎尖培养过程中,不同甘薯品种适宜的NAA/6BA配比存在显著差异,在实际生产中应根据品种特性来进行调整激素的用量和比例。     

十里香茶离体培养及再生体系研究

为了保护珍贵的十里香茶树资源,掌握利于十里香茶的最优组培条件,本研究对十里香茶组培过程中外植体类型、消毒时间、培养基添加物及培养条件进行了筛选。结果表明,采用轻微木质化的带腋芽茎段经升汞消毒15 min,接种后暗培养5 d,MS+0.2 mg·L^-1 NAA培养基中添加3 mg·L^-1 PVP+2000 mg·L^-1 Vc或者6 mg·L^-1 PVP+3000 mg·L^-1 AC,可在低污染率的前提下将褐化率降为10%左右,一定程度上解决了茶树组培中褐化率高的难题;采用1/8 MS+1 mg·L^-1 IBA培养基有利于外植体生根且增殖迅速。本研究建立了十里香茶的无菌苗离体培养及再生体系,可通过组培手段对其进行大量繁殖。     

高山马铃薯脱毒苗DNA甲基化的MSAP分析

为了解脱毒对高山马铃薯试管苗DNA甲基化水平的影响,探究DNA 甲基化在高山马铃薯脱毒后的作用,结合毛细管电泳检测技术对怀玉山高山马铃薯脱毒苗的基因组DNA甲基化进行MSAP分析。结果表明,怀玉山高山马铃薯常温继代带毒苗甲基化水平较高,经过玻璃化法超低温保存处理但未能脱毒时其甲基化水平有所下降,但甲基化仍处于较高水平,而常规茎尖培养脱毒和玻璃化法超低温疗法脱毒可明显降低试管苗的甲基化水平,且玻璃化法超低温疗法脱毒苗的甲基化水平更低。在怀玉山高山马铃薯超低温保存(未能脱毒)、茎尖常规培养脱毒和超低温疗法脱毒3个处理方式中,去甲基化模式和甲基化模式并存,但均以去甲基化模式为主要趋势,且在去甲基化模式的强弱依次为超低温疗法脱毒>茎尖常规培养脱毒>超低温保存(未脱毒)。本研究结果为怀玉山高山马铃薯脱毒苗的种质保存和规模化生产提供了一定的理论依据。     

响应面法优化绿僵菌产绿僵菌素A的培养条件

【目的】优化绿僵菌Metarhizium anisopliae产绿僵菌素A的培养条件,提高绿僵菌素的产量。【方法】应用响应面法设计试验,以Plackett-Burman试验设计和中心组合试验设计筛选得到影响绿僵菌液体发酵的关键因素。【结果】试验得到1个拟合程度高、误差小的模型,该模型给出的最佳培养条件为:蔗糖22.7 g·L~(–1)、蛋白胨13.4 g·L~(–1)和发酵时间9.70 d,预测绿僵菌素A最大质量浓度为6.90μg·mL~(–1),实际测得质量浓度为6.89μg·mL~(–1)。【结论】结果可为绿僵菌大规模发酵获得粗毒素提供理论依据,使绿僵菌粗毒素的广泛开发与应用成为可能。