魔芋快繁体系建立和人工种子研制

附加1mg/1NAA 和1mg/1BA 的 MS 培养基,既适于花魔芋块茎愈伤组织诱导,也适于继代培养。愈伤组织在0.05mg/1NAA 和1mg/1BA 培养基上,芽分化率较高。在无植物生长调节剂的培养基上,芽生长较快且粗壮。在未消毒土壤中,加有多种抗菌剂的魔芋芽型人工种子的转化率为12.5％,比不加抗菌剂的人工种子转换率高1倍多。     

用发酵剂改良的风干香肠微生物特性的研究

为了改良风干肠的品质 ,试验把发酵剂人工接种入风干肠中 ,并且以自然发酵肠和直接烘烤的干肠作对照 ,通过对发酵和烘烤过程中微生物指标的研究 ,以及对产品的感官评定来鉴定其品质。结果表明 ,在发酵和烘烤过程中 ,乳酸菌为优势菌群     

RESPONSE OF ORNAMENTAL SUNFLOWER CULTIVARS ‘SUNBEAM’ AND ‘MOONBRIGHT’ TO IRRIGATION WITH SALINE WASTEWATERS

To explore the possibility that saline wastewaters may be used to grow commercially acceptable floriculture crops, a study was initiated to determine the effects of salinity on two pollen-free cultivars of ornamental sunflower (Helianthus annuus L.). ‘Moonbright’ and ‘Sunbeam’ were grown in greenhouse sand cultures irrigated with waters prepared to simulate wastewaters commonly present in two inland valley regions of California: 1) San Joaquin Valley (SJV) where saline-sodic drainage waters are dominated by sodium (Na⁺) and sulfate (SO ^2? ₄ ) and 2) Coachella Valley (CV) where major ions in tailwaters are Na⁺, chloride (Cl^?), SO ^2? ₄ , magnesium (Mg²⁺), calcium (Ca²⁺), predominating in that order. Ten-day-old seedlings were subjected to five salinity treatments of each water composition, each replicated three times. Electrical conductivities (EC) of the irrigation waters were 2.5, 5, 10, 15, and 20 dS·m^?1. Flowering stems were harvested when about 75% of the ray flowers were nearly horizontal. Stem length and fresh weight, flower and stem diameter were measured. Mineral ion concentrations in upper and lower stems, upper and lower leaves were determined. Sodium was excluded from the young tissues in the upper portions of the shoot and retained in the basal stem tissue. Inasmuch as sunflower is also a strong potassium (K)-accumulator, K⁺/Na⁺ selectivity coefficients were unusually high in the younger shoot organs. Despite a five-fold increase in substrate Ca²⁺ in both solutions, shoot-Ca decreased as salinity increased and this cation was retained in the older leaves. A few of the lower leaves of plants irrigated with ICV waters at EC = 10 dS·m^?1 and higher, exhibited necrotic margins which were undoubtedly caused by high concentrations of Cl^? in the tissues. Flowering stems produced in all treatments met florist quality standards in terms of diameters for stems (0.5 to 1.5 cm) and blooms (8 to 15 cm). Across treatments, stem lengths ranged from 60 to 175 cm. Both ornamental sunflower cultivars proved to be good candidates for production of marketable flowering stems using moderately saline wastewaters.     

Nutrient composition of groundnut cultures (Arachis hypogaea L.) in relation to their kernel size

Seven varieties of groundnuts of varying kernel size were selected to study the relation between kernel size and nutritional quality. Results indicated that no significant (r=0.22) difference was found in oil contents among the various varieties which ranged from 46–52 percent. Protein contents ranged from 17–25.2 percent. Protein content of small seed varieties was high compared to bold seeded varieties, whereas sugar content of bold seeded varieties was higher. No significant differences in amino acid and fatty acid compositions were observed among the varieties tested. In vitro digestibility of protein tended to be slightly less but not significantly so in bold seeded varieties compared to small and medium size varieties. Niacin content of bold seeded varieties was slightly higher compared to other varieties.     

从尹湾汉简看两汉文吏

在西汉末年东海郡有正式编制的吏员中,少吏占吏员的绝对多数。不论是由少吏升迁为长吏,还是由长吏迁转为其它长吏,以实际才干升迁者都占很高的比例,因儒学素养而获升迁者在二者中所占比例都非常低。尽管由于儒学被视为官方意识形态,及其与仕进制紧密结合,促使部分文吏学习儒家经典,有些少吏因此而升为长吏,跻身士大夫,但是,文吏作为一种官僚类型,是始终存在的,而且仍然在官僚队伍中占绝大多数,缺乏儒学素养也仍然是这一群体的主要特征。在两汉四百年间,在官僚队伍的各级长吏中,儒生所占的比例不断增加,并逐渐取得优势地位,而文吏则最     

双江古茶树资源、价值及农业文化遗产特征

云南临沧市双江具有悠久历史的古茶树群落,是世界茶起源地之一的强有力见证,也为双江未来茶产业的发展打下了坚实的基础;通过研究双江古茶树的资源现状、价值分析和文化分析,得出双江茶树资源系统有丰富的双江茶树遗传资源多样性、相关物种多样性以及与茶相关的技术和传统文化的多样性,具有多重价值,对双江茶树资源的保护和利用,对当地人民的生活水平的提高,对双江茶树品种的多样性、相关物种的多样性、传承文化等方面有很大价值;双江古茶树资源具有农业文化遗产广泛的特征,需要申请为全球重要农业文化遗产保护试点。     

天津地区鸡传染性支气管炎病毒的血清型鉴定

对天津地区分离的 7株鸡传染性支气管炎病毒和 3株标准株用气管环中和试验进行血清学分型 ,结果表明 ,呼吸型标准株 M41对其它分离株有较高的交叉保护作用 ,标准肾型 Gray株与天津地区肾型分离株 JS,F,GK1的相关系数分别为35 .43,2 1.45 ,18.41,高于肾型株 Aust- T株与相应分离株的相关系数 (分别为 16 .0 8,12 .41,14 .2 3) ,表明天津地区肾型分离株更接近于 Gray株。腺胃分离株之间的相关系数在 2 2 .71～ 74.16之间 ,明显高于其对呼吸型与肾型分离株 ,表明腺胃型分离株的血清型较特殊     

盾叶薯蓣组织培养及微块茎的离体诱导

用３种不同的繁殖技术进行盾叶薯蓣组织培养,其中以离体诱导微块茎的形成为最有效的方法,ＢＡ与ＫＴ质量浓度分别为４．０￣８．０,１．０￣２．０ｍｇ／Ｌ时,最有利于盾叶薯蓣微块茎的形成,将之接种到含有ＮＡＡ的培养基上后易生根形成小植株。     

Outdoor mass microalgae production in Bahia Kino, Sonora, NW Mexico

The diatom Chaetoceros muelleri was grown in outdoor mass cultures under the winter, spring and summer conditions of Bahia Kino, Sonora, NW Mexico. The solar irradiance in winter was close to 60% of that available in spring and summer, but the cell concentrations and the harvestable biomass were one order of magnitude higher in spring and summer than in winter. There was no difference between the biomass harvested after 2 and 3 days in winter and summer, whereas in spring it was higher after 3 days. The protein content was significantly lower in winter, and carbohydrates and lipids were higher in winter and spring. The number of cells and the amount of harvestable biomass of outdoor cultures of C. muelleri depend on the temperature prevailing in each season, which causes significant differences in growth rates and in biochemical composition.     

干扰水稻瘤矮病毒(RGDV)非结构蛋白(Pns12)的表达抑制病毒在介体昆虫培养细胞内的复制

水稻瘤矮病毒(Rice gall dwarf virus,RGDV)属呼肠孤病毒科(Reoviridae)植物呼肠孤病毒属(Phytoreovirus),由介体电光叶蝉(Recilia dorsalis)以持久增殖型方式传播,其基因组第12条片段编码的非结构蛋白(nonstructural protein,Pns12)是提供病毒复制和子代病毒粒体装配场所——病毒原质(viroplasm)的组分之一。为了明确Pns12在RGDV侵染介体电光叶蝉培养细胞中的功能,本研究通过原核表达的Pns12蛋白免疫注射兔(Oryctolagus cuniculus),制备Pns12抗体,并应用免疫荧光标记和RNA干扰(RNA interference,RNAi)技术研究Pns12在介体培养细胞内的定位和参与病毒原质形成的过程。共聚焦显微镜观察到,病毒侵染的细胞中,与荧光素交联的Pns12抗体特异地标记在病毒原质上。干扰Pns12蛋白表达后,可有效地阻碍病毒原质的形成、子代病毒粒体的组装和病毒非结构蛋白Pns12和外壳蛋白P8蛋白的表达,表明Pns12作为病毒原质的组分参与了RGDV在介体培养细胞内的复制。也表明,Pns12可作为理想的靶标用于阻断电光叶蝉携带和传播RGDV。