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101.
北虫草商品化栽培技术的研究   总被引:1,自引:0,他引:1  
对4个北虫草菌株、5个培养基配方和3种栽培容器进行了北虫草栽培试验研究,并从经济效益方面对其进行了估算分析.结果表明:金地一号菌株优质、高产、商品性好、经济效益高,可作为今后北方地区室内栽培的当家优良菌株进行推广种植;小麦培养基栽培北虫草,不仅产量高、质量好,而且成本低,故采用小麦培养基更具有优势;塑料瓶栽培北虫草,具有重量轻、利于灭菌、可多次重复使用等特点,可作为今后商品化、规模化、工厂化栽培北虫草之首选容器.  相似文献   
102.
Among 19 bacterial strains isolated in Yunnan from rhizosphere soils and plant tissues, Bacillus methylotrophicus strain R2-2 and Lysobacter antibioticus strain 13-6 exhibited the highest antagonistic activity against the tomato root-knot nematode Meloidogyne incognita in plate and greenhouse pot experiments. The two strains, when applied as soil drenches or seed treatments in greenhouse experiments, reduced root-knot severity and incidence on tomato compared to no-bacteria controls. In tomato field trials conducted in separate years, soil drench treatment with either strain reduced root-knot disease levels and increased yields compared to the control. Levels of disease control and yield enhancement provided by the strains were higher than those using the chemicals abamectin and carbofuran. This is the first report of B. methylotrophicus being used as a biocontrol agent against a plant parasitic nematode and the first demonstration that B. methylotrophicus and L. antibioticus can suppress disease caused by root-knot nematodes in the field.  相似文献   
103.
The free range production system is becoming more common in Australia and is expected to increase. Free range hens are exposed to more stressors in comparison to hens from barn and cage systems and it is suggested that stress can increase bacterial shedding on eggs. The aims of this study were to examine the level of total bacteria and Enterobacteriaceae populations, as well as the presence of Salmonella and Campylobacter, in eggs collected from two free range flocks on two different farms and to conduct longitudinal observations of the behaviour and welfare of hens in the free range production system. Hen age (weeks) was shown to have a significant effect (increase) on the level of total bacteria on the egg shell surface and in shell pores, as well as having an effect on feather condition score. As the hens aged, the frequency of external visual egg characteristics increased, as did feather condition score (where feather condition was poorer). These observations indicate areas which should be investigated further to improve the food safety of eggs and optimise the welfare of free range hens.  相似文献   
104.
微生物对长白鱼鳞云杉木材渗透性的影响   总被引:6,自引:3,他引:6  
鲍甫成  吕建雄 《林业科学》1991,27(6):615-621
本文利用水池贮存处理木材研究了细菌对改善长白鱼鳞云杉木材渗透性的有效性。渗透性的测定采用水上升置换气流法。试验结果表明,水池贮存处理长白鱼鳞云杉气干材10周,不仅可以非常显著地增加其边材的渗透性(渗透性平均增加29倍),而且其心材渗透性亦有明显改善(平均渗透性增加1.52倍)。但心材试样渗透性增加不均匀,仅有50%的心材试样在水池贮存处理后渗透性得到了增加。渗透性增加的原因主要是由于边材和部分心材试样受到短芽孢杆菌(Bacillus brevis)等细菌的侵蚀,据电镜观察,边材大多数具缘纹孔的纹孔塞被细菌降解后形成空洞,心材的管胞内壁及具缘纹孔的纹孔缘上有细菌存在。  相似文献   
105.
利用纳米SiO_2表面羟基,与不同的硅烷偶联剂以及叔胺反应制得了2种季铵化纳米Si0_2,对产物进行了表征、抑菌性评价,并对产物浸渍改性处理后竹材的疏水性进行研究。结果表明:1)2种合成方法均制得了季铵化纳米Si0_2,Zeta电位为正值,平均粒径QASN-1纳米SiO_2QASN-2。2)抑菌圈试验表明,季铵化纳米SiO2_对竹材8种主要侵害菌有不同程度的抑制作用。3)经过改性的竹块表面由亲水性变为疏水性,且水接触角减小的速度要小于改性前的。由此可见,季铵化纳米Si0_2可用于竹材的侵害菌防护和防水。  相似文献   
106.
ABSTRACT

During 2008–2011, model field experiments were carried out at the Joni?k?lis Experimental Station of Lithuanian Research Centre for Agriculture and Forestry on a clay loam Endocalcaric Endogleyic Cambisol. The study was aimed to establish the comparison of various postharvest practices (mineral nitrogen fertiliser alone or together with a bioactivator Penergetic k, livestock slurry, red clover biomass and straw incorporation in the soil by a stubble cultivator at a 10 cm depth) on the acceleration of the initial (nine-month period) decomposition of winter wheat straw. During this period, straw mass decomposition intensity was 20.7–29.1%, carbon (C) concentration decreased by 6.5–22.8%, while an increase in nitrogen (N) by 1.1–2.2 times was observed. The highest straw decomposition rate was recorded when after straw incorporation autumn was warm and humid. That year straw mass C to N ratio (C/N) was 38–46. Under less-favourable autumn conditions, the highest decomposition of straw was achieved, having applied mineral N (with and without Penergetic) and livestock slurry and having incorporated the straw in the soil (C/N = 40–55). A slower decomposition rate was observed for the straw spread on the soil surface with mineral N addition or on undersown red clover.  相似文献   
107.
齐安国  张毅川  周建 《安徽农业科学》2006,34(3):412-412,423
从培养基、碳源、温度、pH值4个方面对菊花、月季、香石竹联合固氮细菌固氮酶活性的影响进行了研究,以求找到三者根际联合固氮菌适合的环境条件。  相似文献   
108.
It is frequently hypothesised that high soil fungal/bacterial ratios are indicative for more sustainable agricultural systems. Increased F/B ratios have been reported in extensively managed grasslands. To determine the shifts in fungal/bacterial biomass ratio as influenced by grassland management and to find relations with nitrogen leaching potential, we sampled a two-year-old field experiment at an organic experimental farm in the eastern part of The Netherlands. The effect of crop (grass and grass-clover), N application rate (0, 40, 80, ) and manure type (no manure, farm yard manure and slurry) on the F/B ratio within three growing seasons was tested, as well as relations with soil and crop characteristics, nitrate leaching and partial N balance. Biomass of fungi and bacteria was calculated after direct counts using epifluorescence microscopy. Fungal and bacterial biomass and the F/B ratio were higher in grass than in grass-clover. The F/B ratio decreased with increasing N application rate and multiple regression analysis revealed a negative relationship with pH. Bacterial activity (measured as incorporation of [3H]thymidine and [14C]leucine into bacterial DNA and proteins) showed the exact opposite: an increase with N application rate and pH. Leaching increased with N application rate and was higher in grass-clover than in grass. Partial N balance was more positive at a higher N application rate and showed an inverse relationship with fungal biomass and F/B ratio. We conclude that the fungal/bacterial biomass ratio quickly responded to changes in management. Grasslands with higher N input showed lower F/B ratios. Grass-clover had a smaller fungal biomass and higher N leaching than grass. In general, a higher fungal biomass indicated a lower nitrogen leaching and a more negative partial N balance (or smaller N surplus), but more observations are needed to confirm the relationship between F/B ratio and sustainability.  相似文献   
109.
20%寡聚酸碘水剂对黄瓜灰霉病的药效试验   总被引:1,自引:0,他引:1  
20%寡聚酸碘水剂(AS)的有效成分为氨基寡糖素与碘的络合物,采用室内生物活性测定及田间药效试验,以50%乙烯菌核利可湿性粉剂(WP)1 000倍液为对照药剂,评价了20%寡聚酸碘AS对黄瓜灰霉病的防治效果。室内抑菌试验结果表明:20%寡聚酸碘AS 1 000倍液、1 500倍液、2 000倍液的抑菌率分别为97.30%、45.90%、14.00%,均低于50%乙烯菌核利WP 1 000倍液(100.00%)。田间药效试验结果表明:20%寡聚酸碘AS 1 000倍液、1 500倍液的田间防效分别为81.66%、74.80%,均高于50%乙烯菌核利WP 1 000倍液(73.87%)。  相似文献   
110.
The aims of this study were to study the prevalence of oviduct abnormalities of buffaloes, investigate bacteria accompanying hydrosalpinx, pyosalpinx and salpingitis. In addition, the study was designed to investigate the correlation between bacterial infection of the uterus and oviduct lesions in buffaloes. Bacteriological examinations were performed on hydrosalpinx, pyosalpinx and salpingitis. Hydrosalpinx was found in 28 (6.9%) cases of which 20 (71.4%) were found unilaterally and 8 (28.6%) bilaterally. Pyosalpinx was recorded in 12 (2.9%). Three cases (0.7%) of oviducts filled with blood were recorded. Obstruction of oviducts was recorded in 5 (1.2%). Adhesions between mesosalpinx and perisalpingeal tissues were observed in 7 (1.7) cases. One case of double oviduct was found in the left side of the tract examined. The most prevalent bacteria recovered from hydrosalpinx were Corynebacterium hemolyticum and Actinomyces bovis, 42.8% and 28.6%, respectively. No correlation was noticed between bacteria isolated from the uterus and hydrosalpinx. The most prevalent bacteria recovered from pyosalpinx were Escherichia coli, Archanobacterium pyogenes and Staphylococcus aureus, 33.3%, 26.7% and 16.7%, respectively. Higher rates of leukocyte infiltration (P < 0.01) were observed in the uterine discharge and pyosalpinx than hydrosalpinx. In a conclusion, the current study disclosed that oviductal lesions seem to be an important problem in buffalo cows. In addition, there is no correlation between bacteria isolated from uterus and hydrosalpinx. There is a high correlation between bacteria isolated from uterus and pyosalpinx and salpingitis. The occurrence of pyosalpinx and salpingitis is mainly due to bacterial infection. Bacterial isolates from pyosalpinx and salpingitis might be related to ascending infection from the uterus.  相似文献   
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