绒毛皂荚离体茎段培养及再生植株的细胞组织学研究

报道了绒毛皂荚离体茎段培养中几种不同的成苗途径，并对其组织分化和器官发生进行了细胞组织学研究，结果表明：以ＭＳ为基本培养基附加一定浓度的细胞分裂素（６ＢＡ）和生长素（ＩＢＡ）在短期内即可诱导带节茎段形成丛状苗，丛苗主要来源于腋芽萌发和腋芽基部分化．愈伤组织在加有生长素的ＭＳ培养基中很容易从茎段切口产生．转移至ＭＳ附加６ＢＡ和ＮＡＡ培养基中能分化不定芽．芽原基起源于愈伤组织近表面的分生细胞团．生长到１．５ｃｍ以上的试管苗可诱导生根，生根培养基中须加入一定浓度的ＩＢＡ．     

Enhancing Corn Production Through the Use of Starter Fertilizer in the Northern Great Plains

Abstract

The northern portion of the Great Plains has environmental conditions that require unique management practices to ensure optimum corn (Zea mays L.) yield and quality. The objective was to investigate the effect of starter fertilizer on corn yield and quality under different soil management. A field experiment was established within a 2‐year corn/soybean [Glycine max (L.) Merrill] rotation. Whole‐plot treatments were tillage with split‐plot treatments of starter fertilizer. Starter fertilizer treatments consisted of two nitrogen (N) sources, each at four rates, all contained phosphorus (P) and potassium (K). An additional treatment of no starter fertilizer was also incorporated into the experiment. There was a significant increase in yield with application of starter‐N for all years except 2002. The most dramatic yield increase was obtained with the comparison between the no starter (no N, P, or K) treatment and the P and K treatment (no N+P and K). Starter fertilizer with only P and K also increased yield, oil production, and N removal in all years compared with no starter fertilizer treatment. Application of starter fertilizer can have a significant positive impact on yield and quality of corn grown in the northern Great Plains.     

低温复合发酵剂对冬季牛粪堆肥微生物多样性的影响

在-20℃下进行冬季牛粪堆肥,研究其温度、可培养微生物数量及细菌种群多样性的变化。堆肥处理的第6 d进入高温期并持续10 d,最高温度67.4℃;对照温度始终在-11～-13℃。处理的可培养细菌、放线菌、真菌数量分别高于对照0.018～1.368、0.040～0.966、-0.778～0.547个数量级;微生物总的变化趋势是细菌最多,放线菌次之,真菌最少。处理不同时期细菌DGGE图谱有着明显的差异性,对照不同时期图谱无明显差异;UPGAMA聚类分析,处理的相似性在0.54～0.70,对照的在0.95～0.98。处理的优势菌:初期为Clostridium ther-mopalmarium、Psychrobacter spp,升温期为Psychrobacter spp,高温期为Hydrogenobacter hydrogenophilus、Clostridiumspp、Psychrobacter spp、Saccharococcus thermophilus等,降温期为Clostridium thermolacticum、Psychrobacter spp;对照的各个时期优势菌相同,为Clostridium spp、Pseudomonas spp、Psychrobacter spp等;整个堆肥过程中Psychrobacterspp为处理和对照的共同优势菌。     

Perineal hernia repair in the dog by transposition of the internal obturator muscle

Summary

A modified technique for transposition of the internal obturator muscle was used to repair perineal hernias in 100 dogs. Complications and long‐term results are described. The most important complications were wound infection (45%), faecal incontinence (15%), and perineal fistula (7%). These complications often occurred in combination. The recurrence rate of perineal hernia was 5%.

Nine of the 15 patients with faecal incontinence had paresis of the external anal sphincter or faecal incontinence before surgery. We suggest that in numerous patients, faecal incontinence is a complication of the condition rather than a complication of treatment. The owner's assessment of the surgical result was good in 71% and moderate in 18% of the cases.     

洋葱伯克氏菌无细胞培养物的生防及促生活性研究

为了防止洋葱伯克氏菌在农业环境中对人类的危害,采用离心和过滤的方法获得洋葱伯克氏菌无细胞培养物,并研究其在平板上对植物病原真菌的拮抗作用和对水稻的促生作用。结果表明：洋葱伯克氏菌对植物病原真菌具有明显的拮抗作用,其中菌株R。、R。,、R。R~o．R：．、R。、R28的抑菌效果显著,在这7株菌中R。表现出对灰霉菌的强烈抑制作用和对稻瘟菌的较强抑制作用,并且表现出明显的促生作用。     

乳酸杆菌抑制致病菌及生物保鲜发酵剂特性评价

以15株乳酸杆菌为研究对象,动物双歧杆菌乳亚种BB-12作为对照,研究它们对肠道致病菌的抑菌特性.结果表明:9株菌对5株指示菌均有较好抑制作用,2株菌对金黄色葡萄球菌、肠炎沙门氏菌、大肠杆菌和蜡样芽孢杆菌均有抑制作用;以抑菌效果、凝乳状态、产酸性能为指标,筛选出4株菌,与嗜热链球菌ST-21组合制备生物保鲜发酵剂;通过...     

Long-term callus cultures of diploid barley (Hordeum vulgare). II. Effect of auxins on chromosomal status of cultures and regeneration of plants

Summary Chromosomal abnormalities increased with time on the relatively high concentrations (2.0mg/l or more) of 2,4-D. Prolonged exposures of cell cultures to high concentrations of 2,4-D significantly increased the percent polyploid mitoses and were also associated with increased abnormalities of the spindle apparatus. Cultures maintained in the presence of NAA had a large number of cells with structural alterations of the chromosomes. The best embryogenic callus production (those maintained on 0.1 and 1.0 mg/l 2.4-D) occurred in cultures with least detectable genetic variation. Plants could not be regenerated from cultures that had been on the maintenance media for seven months or more. The loss of regeneration potential was uniform across the concentrations and auxins tested, and only correlated with time. This loss could not be associated directly with detectable genetic variation.     

全球化进程中如何抵制外来文化的负面影响

经济全球化趋势不可阻挡。它给我国文化建设带来的负面影响主要有 :推行资本主义价值观 ,对社会主义意识形态构成威胁 ;文化同质性现象对我国传统文化造成很大冲击 ;西方“文化垃圾”严重污染社会环境 ,毒害青少年的身心健康 ;抢占中国文化市场 ,给我国稚嫩的文化产业带来巨大竞争压力。我们的应对措施是 :大力发展社会主义先进文化。     

Biodegradation of the herbicide bromoxynil and its plant cell wall bound residues in an agricultural soil

The mineralization and formation of metabolites and nonextractable residues of the herbicide [¹⁴C]bromoxyniloctanoate ([¹⁴C]3,5-dibromo-4-octanoylbenzonitrile) and the corresponding agent substance [¹⁴C]bromoxynil ([¹⁴C]3,5-dibromo-4-hydroxybenzonitrile) was investigated in a soil from an agricultural site in a model experiment. The mineralization of maize cell wall bound bromoxynil residues was also investigated in the agricultural soil material. The mineralization of [¹⁴C]bromoxynil and [¹⁴C]bromoxyniloctanoate in soil within 60 days amounted up to 42 and 49%, respectively. After the experiments, 52% of the originally applied [¹⁴C]bromoxynil and 44% of the [¹⁴C]bromoxyniloctanoate formed nonextractable residues in soil. Plant cell wall bound [¹⁴C]bromoxynil residues were also mineralized to an extent of about 21% within 70 days; the main portion of 76% persisted as nonextractable residues in the soil. In bacterial enrichment cultures and in soil two polar metabolites were observed; one of it could be identified as 3,5-dibromo-4-hydroxybenzoate and the other could be described tentatively as 3,5-dibromo-4-hydroxybenzamide.