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991.
Growth, nodulation and nitrogen (N) fixation efficiency of Banki (Local) and ICGS-44 (exotic) varieties of groundnut was significantly ( P < 0.05) improved by their inoculation either with NC-92 or Rudy Patric (R.P.) strains of rhizobium. Nodules did not form without inoculation in plants growing in sterilized sand. Inoculation with R.P. strain of rhizobium resulted in greater shoot growth, N content in shoot and number and weight of nodules in groundnut varieties. The R.P. inoculant increased agronomic efficiency by 112.5 % in Banki and 100 % in ICGS-44 variety of groundnut. Improvement in N fixation efficiency by inoculation with R.P. inoculant was 334 and 286% in Banki and ICGS-44 variety, respectively. However, Physiological efficiency was maximum in Banki variety when inoculated with NC-92 strain of rhizobium. 相似文献
992.
在我国新发现的一种牛的泰勒虫(Theileria)未定种 总被引:7,自引:0,他引:7
对分离自我国西北某地自然感染牛体的一株泰勒虫(Theileria)未定种,进行了接种试验、形态学观察和部分传播试验。结果表明,该种可在除脾牛体内大量繁殖,寄生物血症达52.69%。虫体形态具多形性:有梨子形、圆环形、椭圆形、杆状、三叶形、边虫样、十字架形,还有许多难以形容的不规则形虫体;在同一红细胞内不同数目的边虫样虫体可发育变大,生成的原生质伸延,而后互相连接或交融,重新构成各种不同形态的虫体; 相似文献
993.
J. Berg Jrgensen 《Acta veterinaria Scandinavica》1978,19(1):58
In 3 experiments, 13 pigs were inoculated orally with 0.5 mg Mycobacterium avium daily for 5 days (1 mg = 32–68×106 viable units). Five to 8 days after inoculation, 16 non-inoculated pigs were added to the inoculated pigs.Cultures from faeces showed excretion of M. avium from all the inoculated pigs for some time within the period 16 to 65 days after the last inoculation; the greatest numbers of organisms (62000 per 100 g faeces) were found at about the middle of the excretion period (Table 2). Two of the contact pigs were found to excrete M. avium in small numbers, 1 at 15, the other at 37 and 44 days after contact.All the inoculated pigs and 13 of the contact pigs showed positive intradermal tuberculin reactions. Post-mortem examination showed tuberculous lesions in all the inoculated pigs (Table 3). M. avium was transmitted to 15 of 16 pigs by contact. Five of these pigs showed gross lesions, 10 of them microscopic lesions only; in 9 of them the infection was proved by culture. 相似文献
994.
在网室内用人工接虫的方法对2个抗虫×抗虫,和7个抗虫×感虫大豆杂交组合的F_2群体,及抗虫和感虫亲本,进行了抗性鉴定。根据抗、感亲本的虫食粒率和受害荚率,将F_2代植株的抗虫性分为5级。结果表明,F_2代的抗虫性呈非对称分布,分布高峰的位置因组合而异,且不具有数量性状特有的中心对称分布特征。2个抗×抗组合的F_2代,均分离出一定比例的感虫或高感个体,暗示父母本可能分别带有不同的抗虫基因。同一抗虫亲本与不同的农艺亲本杂交后,F_2代的抗虫性分离比例有较大的差异。抗×抗和抗×感组合的F_2代,都可以分离出较大比例的抗虫单株,超亲现象很普遍,因此,在适宜的接种强度下,抗食心虫性的选择,可能比选择其它数量性状更易奏效。 相似文献
995.
M. Koppel 《Potato Research》1993,36(3):183-188
Summary The susceptibility to soft rot caused byErwinia carotovora subsp.atroseptica of five potato cultivars and potato clones from the potato breeding programme at J?geva Plant Breeding Institute was assessed
in a laboratory test. Three test methods were used: a single site inoculation, vacuum infiltration and slice inoculation.
The severity of the disease varied widely with the different methods, which gave different cultivar rankings. 相似文献
996.
In H. cannabinus mutagenic efficiency and effectiveness of EMS decreased with increase in concentration after excised mature embryo treatment whereas, a reverse trend was observed following seed treatment. Comparatively, maximum effectiveness vis-à-vis mutation induction was obtained at 0.1 % EMS after mature embryo treatment. The chlorophyll and other mutational spectra were also examined and discussed. 相似文献
997.
近年来,如何提高中职学校德育课教学实效,让德育课课堂焕发新的活力成为教学工作的一大课题.通过建立融洽的师生关系,提升教师业务知识水平,改变教学方法等方面来激发学生的学习兴趣,从而达到提高课堂教学实际效果. 相似文献
998.
湖北省棉花黄萎病病菌致病力分化研究 总被引:1,自引:0,他引:1
采用无土育苗和裸苗接种后移栽的方法,对2007-2008年间采自湖北不同地区的32个棉花黄萎病菌菌株和4个对照菌株进行了致病力鉴定。结果表明,强致病力菌株有12个,占鉴定菌株总数的33.3%,中等致病力菌株有19个,占52.8%;弱致病力菌株有5个,占13.9%。该结果表明,湖北存在强致病力的黄萎病菌,而且强致病力菌在该省的三大植棉区均有分布。对不同鉴别寄主对各菌株的反应分析显示,采用无土育苗和裸苗接种相结合的鉴定方法是一项不错的鉴定方法。 相似文献
999.
中国农户复合(混)肥施用效果分析 总被引:3,自引:0,他引:3
近10年来中国肥料快速走向复合化,复合(混)肥是拉动肥料产业发展的主要力量。本研究基于农业部测土配方施肥农户调研数据,对全国6个省的1143户农户水稻、小麦和玉米三大粮食作物的复合(混)肥施用现状及效果进行分析。结果表明,复合(混)肥中提供的氮磷钾养分已经占肥料投入总量的32.1%、57.0%和58.2%,其中氮复合化水平超过西欧水平。施用复合(混)肥导致三大粮食作物养分投入数量平均增加12.2%,肥料成本平均增加26.7%,但在不同作物上的增产效果差异较大,其中玉米上施用各种类型复合(混)肥均能显著增产,增产幅度平均达29.9%,有部分复合(混)肥配方在水稻上增产,大部分复合(混)肥在小麦上不增产。复合(混)肥配方制定不科学、施用不科学及假冒伪劣过多是主要原因。 相似文献
1000.
Nadine R. Sousa 《Soil biology & biochemistry》2011,43(10):2115-2120
The area occupied by Pinus pinaster in Portugal is rapidly diminishing because of forest fires. Ectomycorrhizal fungi form obligate, mutually beneficial associations with P. pinaster which improve plant growth and resistance to adverse conditions. The aim of this work was to assess whether native ectomycorrhizal fungi could be a useful tool in the reforestation of burned areas. The work was conducted in a forest nursery greenhouse, where P. pinaster seedlings were inoculated with compatible ectomycorrhizal fungal isolates: Suillus bovinus, Pisolithus tinctorius, Rhizopogon roseolus, and a mixture of the three fungi, using burned and unburned forest soil as substrate. Inoculation significantly enhanced the growth of P. pinaster, with R. roseolus proving to be the most effective in burned soil, with an 8-fold increase in plant fresh weight. Overall, inoculation stimulated growth most in burned than in unburned soil.This study suggests that inoculation with selected ectomycorrhizal fungi in containerised nurseries can be an advantageous approach for the successful establishment of P. pinaster in burned soil. The obtained results point out to the interest of extending these studies into fire-impacted areas, using ectomycorrhizal fungi as a biological tool. 相似文献