Pink-pigmented facultative methylotrophic bacteria accelerate germination, growth and yield of sugarcane clone Co86032 (Saccharum officinarum L.)

The existence of Methylobacterium as a symbiont with sugarcane and its influence on crop growth at various stages was examined. Pink-pigmented facultative methylotrophic bacteria (PPFMs) strains isolated from different parts of the sugarcane clone Co86032 showed growth on methanol, and were further confirmed based on the mxaF gene encoding the -subunit of the methanol dehydrogenase by polymerase chain reaction amplification using specific primers. True seeds inoculated with PPFMs had a higher germination percent and rate of germination than the control. A combined treatment of seed imbibition, soil application and phyllosphere spray increased specific leaf area, plant height, number of internodes, and cane yield. Immunological determination of cytokinin in young and mature leaves significantly increased when the epiphytic population on the leaf surface increased. Trends in sugar qualities in the form of Pol (sucrose) % in cane, Brix % in cane, and commercial cane sugar were similar to that of cane yield. These effects might be mediated by the production or synthesis of plant hormones.     

麦后复种短期兼用绿肥引种试验研究

对引进的 4份短期兼用绿肥品种从鲜荚产量、产值、青干草、根量及对土壤肥力影响测定分析 ,选出美国供给者豇豆是一种优良的短期肥菜、肥食兼用的绿肥品种 ,可供生产中大力推广应用     

几种早熟禾及其人工杂种染色体数目变化的特异性

通过对3个草地早熟禾品种莫诺波利、瓦巴斯、恩托佩和变种扁秆早熟禾及其人工杂种染色体的观察计数，指出每种早熟禾染色体数没有一个固定的值，而是一个变化范围，有1－2个众数，基本上是以7为基数变化的，同时对这种变化的遗传基础进行了分析探讨。     

9种瘿蚜的Wolbachia分子检测和系统发育分析

[目的]以五倍子蚜、杨树瘿蚜和黄连木瘿蚜等9种瘿蚜为实验材料,探讨瘿蚜Wolbachia与其它自由生活蚜虫携带的Wolbachia的株系差异及亲缘关系,明确五倍子蚜、杨树瘿蚜和黄连木瘿蚜等9种瘿蚜的Wolbachia感染情况、株系及系统发育关系。[方法]从田间采集新鲜虫瘿,将蚜虫转移到离心管内,100%乙醇-20℃保存。采用Wolbachia的16S rRNA、wsp、fts Z、gro E和glt A基因引物,以瘿蚜的总DNA为模板进行扩增、测序和分析,联合NCBI中Wolbachia 16S rRNA相关基因序列进行系统发育分析。[结果]在检测的9种瘿蚜中,有3种瘿蚜共3个种群感染有Wolbachia,其中滇叶瘿绵蚜昆明种群的Wolbachia属于B超群,肚倍蚜昆明种群和角倍蚜峨眉种群的Wolbachia可能属于新发现的O超群。[结论]与自由生活的蚜虫相比,瘿蚜的Wolbachia感染率偏低,且株系间的差异较大。     

In vitro rescue of zygotic embryos of sour orange, Citrus aurantium L., and their detection based on RFLP analysis

Embryo development in vivo has been studied in four Citrus aurantium L. polyembryonic genotypes. Seeds were collected 65, 85, 105, 125 and 220 days after pollination (DAP). None of the immature seeds harvested 65 and 85 DAP contained visible embryos. A single embryo at a more advanced developmental stage was observed in the central position at the micropylar apex of the embryo sac in about 74% of seeds harvested at 105 DAP, while at 125 and 220 DAP the majority of seeds had two or more embryos at the same developmental stage crowded together. Restriction fragment length polymorphism (RFLP) analysis of lowand high-copy-number nuclear DNA was used to distinguish zygotic from nucellar seedlings. Analysis of plantlets derived from in vitro culture of the bigger embryos, located in the central position at the micropylar apex of the embryo sac of seeds harvested at 105 DAP, established that the frequencies of zygotic embryos ranged from 82 to 88%. Media for immature embryo germination in vitro were based on the nutrients and vitamins of Murashige and Skoog (MS) and Murashige and Tucker (MT) media supplemented with various concentrations of sucrose and growth regulators. A total of 76% of globular stage embryos (<0.3mm) germinated on MT medium containing 150 mM sucrose and 14.4 μM gibberellic acid. Heart stage embryos (0.3-0.8 mm) germinated at 95% on MT medium supplemented with 150 mM sucrose and 2.9 μM gibberellic acid. The addition of 500 mg/l malt extract to MS medium increased the germination of early cotyledon stage (0.8-2.0mm) embryos to 98%. The optimum sucrose concentration for embryo rescue was 150 mM for the three embryo developmental stages. The ability to form plants in vitro strongly increased with increasing embryo developmental stage.     

1株黄原胶降解菌的鉴定

对从野外土壤中分离得到的1株可降解黄原胶的兼性厌氧菌进行了鉴定。结果表明,该菌株在幼龄时期为杆菌,大小约为(0.4~0.6)μm×(1.0~2.0)μm,呈直杆形或稍弯曲杆形,但在1周以上的培养物中,只存在大小约为0.5μm×0.5μm的类球状细胞;该菌为革兰氏阴性,兼性厌氧,无运动性,不形成芽孢,能利用多种糖类基质。初步鉴定该菌为鞘氨醇单胞菌(Sph ing om onas)。     

设施栽培土壤甲烷氧化的研究

研究了设施栽培土壤的甲烷氧化.结果表明,不同土壤对甲烷的氧化能力各异,可能与土壤的理化性质有关;土壤微生物是甲烷氧化的主要生物类群:土壤含水量对甲烷氧化有明显影响,含水量过高或过低对甲烷氧化均具有抑制作用;氮源(包括有机和无机氮源)对甲烷氧化均有抑制作用;不同碳源对甲烷氧化的影响各异,纤维素对甲烷氧化抑制作用最小,而高浓度的甲醇、葡萄糖则对甲烷氧化具有强烈的抑制作用;在甲烷氧化过程中加入葡萄糖能迅速抑制甲烷氧化;在加入葡萄糖的同时保持瓶中充足的氧气,则这种抑制作用可以在5.5 d后得到解除.此外,还研究了从土壤中分离的甲烷氧化菌对碳源的利用情况,表明在甲烷释放极少的设施栽培土壤中,兼性营养的甲烷氧化菌可能在甲烷氧化中占据主要的地位.     

秸秆对猪粪静态兼性堆肥无害化和腐熟度的影响

为促进猪粪静态兼性堆肥产品无害化和腐熟,通过添加玉米秸秆调控堆体物理结构特性和碳氮比,采用传统自然发酵方式进行为期90d的静态兼性堆肥试验,分别设置纯猪粪处理(P)和秸秆调控处理(PC)研究静态兼性堆肥过程腐熟度指标、粪大肠菌群以及微生物群落结构演变特征。结果表明,秸秆调控增加了堆体孔隙率(提高19.41%),促进氧气向堆体内部扩散,增强了好氧微生物对有机质的降解,降低NH₄⁺-N,可溶性有机氮(dissolved total nitrogen, DTN)等植物毒性物质含量,提升了堆肥腐熟度,两组处理堆肥产品种子发芽指数分别为40.84%(P)和114.60%(PC)。静态兼性堆肥经过30～40 d自然发酵后,粪大肠菌群数量达到卫生安全标准,堆体温度、NH₄⁺-N和有机酸含量均会影响粪大肠杆菌的活性。堆体中微生物以厚壁菌门、放线菌门、变形菌门等与木质纤维素降解相关的菌门为优势菌门,堆体自上而下由好氧菌属演替为厌氧菌属,并形成好氧、兼性、厌氧的微生物分层。秸秆调控增加了堆体的好氧区域,促进和提高了猪粪...     

小麦和无融合生殖小麦草杂交后代(BC_2F_2)的生物学特性及根尖染色体数目变化研究

对小麦 (Triticumaestivum)和无融合生殖小麦草 (Elymusrectisetus)的杂种后代 (BC2 F2 )生物学特性和根尖染色体数目变化情况进行了的研究。结果表明 ,BC2 F2 的生物学特性处于小麦和小麦草之间 ,但更趋向于小麦 ,这是由于杂交后代经 2次回交所致。根尖染色体检查发现 ,BC2 F2 的体细胞染色体数目存在 1个很大的变异范围 ,从 2 9条到 6 9条不等 ,但大部分细胞内的染色体数目是 42条。杂种后代的体细胞染色体数目的变化一方面与远缘杂交有关 ,另一方面可能与无融合生殖具有一定的联系     

耐低温兼性厌氧蛋白酶产生菌192的筛选、鉴定及酶学性质

为了提高厌氧水解效率,采用双层平板法筛选出一株耐低温兼性厌氧蛋白酶产生菌192.经形态、生理生化和16S rDNA序列分析鉴定为蜡状芽孢杆菌(Bacillus cereus),对其产酶条件进行了初步研究.结果表明,该茵的最适生长温度为30℃,生长8～12h达对数期,初始pH 7.5时酶活力最高.蛋白酶最适反应温度为45℃、pH 7.0,酶活力最高达39.3 U/mL.该酶在50℃以下,pH 6.0～9.0性能稳定.在60℃以上热稳定性很差,70℃保存lh酶活力全部丧失.