含锌酵母的培养试验研究   总被引：2，自引：0，他引：2  

陈佩林  詹文毅  叶辉 《动物医学进展》2003,24(3):62-64

以酵母菌 IFO2 346菌株为菌种 ,在基础培养基中加入适量的锌离子 ,经发酵试验获得高锌酵母产品。对该株酵母的最适生长条件进行了初步研究。结果表明 :该菌在无机锌浓度为40 0 μg/ m L、接种量为 10 %、最适 p H值为 6左右、碳源为蔗糖、氮源为磷酸二氢铵的培养条件下 ,干酵母含锌量达 80 mg/ g,该研究取得了较为满意的结果  相似文献   

稻瘟病防治必须注意五个问题   总被引：1，自引：0，他引：1  

李春富  吉连素  范文平  徐凤芝  李敏 《北方水稻》2003,(3):33-34

简述了木兰县近几年稻瘟病的发病条件、原因及危害程度。指出菌源是该病发生的先决条件。在防治上不要与胡麻叶斑等细菌性病害相混。分析了不同防治时期、不同防治药剂的防治效果。对提高防效提出了4点参考建议。  相似文献   

大花蕙兰温室管理技术   总被引：1，自引：0，他引：1  

张江丽  孙艳香  冯会娟  管立峰  胡俊华 《北方园艺》2008,(7)

从大花葱兰的温室培养所需要的各种条件:温度、相对湿度、光照、栽培基质、水、肥以及病虫害等方面,对大花蕙兰的温室管理进行了讨论,并对其管理过程提出了相应的措施.  相似文献   

食料条件对稻纵卷叶螟生长发育和繁殖的影响   总被引：5，自引：0，他引：5  

但建国  陈常铭 《植物保护学报》1990,17(3):193-199

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狗牙根内生固氮菌生长条件     

刘天增  毛中伟  张巨明 《草业科学》2016,33(5):835-842

从已分离的多个狗牙根(Cynodon dactylon)内生固氮菌株中筛选到两株固氮酶活性较高的菌株7D和BM13,为明确固氮菌株对环境因子的适应性,研究了在不同的生长环境条件下菌株的生长量。采用Ashby无氮培养基,测定了温度、pH、渗透压以及不同氮源和碳源等环境条件对固氮菌生长的影响。结果表明,在10~40℃的温度范围内、pH值3.92~9.64的酸碱环境和30g·L~(-1) NaCl的高渗透压下,固氮菌7D和BM13均能正常生长;菌株能耐受0~10mmol·L~(-1)的NH_4~+和NO_3~-,而且能利用蔗糖、甘油、麦芽糖、甘露醇和葡萄糖等多种碳源生长。说明狗牙根内生固氮菌株7D和BM13对环境因子有很强的抗逆性和适应性,但两菌株之间存在一定差异,可望进一步研发成为优良的固氮微生物肥料生产菌种。  相似文献   

Mutation Breeding and Optimization of Enzyme-producing Condition of Bacillus lichenniformis Producing Cellulase     

YU Zu-hua  DING Ke  HOU Kui  LI Yuan-xiao  LI Wang  LIU Yi-chen  CAO Ping-hua  JIA Yan-yan  CHENG Xiang-chao 《中国畜牧兽医》2016,43(4):1006-1011

In order to improve the ability of producing cellulase of Bacillus lichenniformis, the mutational strain was screened after Bacillus lichenniformis LY02 was induced by UV.Then the best optimal enzyme-producing condition, inoculum size, temperature, incubation time, initial pH and metal ions were studied.The results showed that the cellulase activity of mutated strain was increased by 34.31%.And the best optimal ferment conditions were as follows:Inoculation concentration was 1.5%, cultivated temperature was 37℃, ferment time was 24 h, initial pH of medium was 5.0, and K⁺ and Ba²⁺ could promote the cellulase producing.These results were contributed to develop the strain to be applied in practice.  相似文献   

Interaction of food resources and landscape structure in determining the probability of patch use by carnivores in fragmented landscapes     

Alessio Mortelliti  Luigi Boitani 《Landscape Ecology》2008,23(3):285-298

Studies on the distribution of mammalian carnivores in fragmented landscapes have focused mainly on structural aspects such as patch and landscape features; similarly, habitat connectivity is usually associated with landscape structure. The influence of food resources on carnivore patch use and the important effect on habitat connectivity have been overlooked. The aim of this study is to evaluate the relative importance of food resources on patch use patterns and to test if food availability can overcome structural constraints on patch use. We carried out a patch-use survey of two carnivores: the beech marten (Martes foina) and the badger (Meles meles) in a sample of 39 woodland patches in a fragmented landscape in central Italy. We used the logistic model to investigate the relative effects on carnivore distribution of patch, patch neighbourhood and landscape scale variables as well as the relative abundance of food resources. Our results show how carnivore movements in fragmented landscapes are determined not only by patch/landscape structure but also by the relative abundance of food resources. The important take-home message of our research is that, within certain structural limits (e.g. within certain limits of patch isolation), by modifying the relative amount of resources and their distribution, it is possible to increase suitability in smaller/relatively isolated patches. Conversely, however, there are certain thresholds above which an increase in resources will not achieve high probability of presence. Our findings have important and generalizable consequences for highly fragmented landscapes in areas where it may not be possible to increase patch sizes and/or reduce isolation so, for instance, forest regimes that will increase resource availability could be implemented. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

Association of vegetation and soil mite assemblages with isolated Scots pine trees on a Scottish wet heath     

Rob W. Brooker  Graham H. R. Osler  Jörn Gollisch 《Landscape Ecology》2008,23(7):861-871

Isolated trees may significantly enhance biodiversity at the landscape level. However, our understanding of their impacts is still poor, particularly in environments with high soil moisture where research on this topic has been comparatively limited. We examined understorey vegetation and soil oribatid mite assemblages under live and dead Scots pine trees and in open treeless areas, all within the same Scottish upland wet heath system, to determine whether isolated live trees affected the understorey and mite components of the ecosystem, and whether these effects occurred in parallel. We also explored whether these responses might result from tree-driven reductions in soil moisture content. Live trees reduced soil moisture (relative to wet heath and beneath dead trees) and appeared to change vegetation from wet heath to dry heath type communities. These effects were strongly related to tree trunk diameter (tree size). No major effects of dead trees on understorey vegetation or soil moisture were apparent. Higher mite species abundance and richness were found under live trees than in treeless open heath. Although mite abundances were lower under dead trees than live trees, richness remained similar, thus different factors seem to be regulating mite abundance and community composition. These findings indicate that landscape-level biodiversity responses to environmental change such as habitat fragmentation cannot be predicted from vegetation patterns alone, and that even in heavily fragmented landscapes comparatively small patches such as isolated individual trees can enhance biodiversity.  相似文献   

黄泥河保护区三种鼬科动物冬季生境选择研究     

朱洪强  朴敏娟  兰佳宇  李灵贝  刘佳琪  朱文宇  阎庚华  程龙 《野生动物学报》2019,(1):75-82

采用样线法对吉林黄泥河自然保护区3种鼬科动物冬季生境选择进行研究,共设置20条样线,记录了40个利用样方和40个对照样方。在每个样方内测定海拔、坡度、坡向、坡位、隐蔽级、郁闭度、灌丛盖度、树胸径、人为干扰距离、林型、裸岩、雪深和倒木共计13类生态因子。运用Bailey's置信区间法分析坡向、坡位、林型、裸岩、倒木等5个名词型变量;利用非参数检验中的2个独立样本Mann-Whitey U检验,分析海拔、坡度、隐蔽级、郁闭度、灌丛盖度、树胸径、人为干扰距离、雪深8个数量型变量;并通过主成分分析法,综合分析了13个因子对3种鼬科动物冬季栖息地选择的影响。结果显示,3种鼬科动物喜欢在阳坡、半阴半阳坡、中坡位的针叶林和针阔混交林中活动,对倒木和裸岩表现出明显选择性;对灌丛盖度的选择差异极显著(P <0. 01),对不同坡度和郁闭度的选择差异显著(P <0. 05);在主成分分析中,前4个主成分中的累积贡献率达到64. 859%,第一主成分贡献率为30. 933%,主要反映利用样方的林型、海拔、雪深和人为干扰距离的影响,第二主成分贡献率为14. 757%,主要反映利用样方的树胸径和隐蔽级影响。3种鼬科动物主要选择食物丰富度高、隐蔽程度高和可以减少能量消耗的地区作为冬季栖息地。  相似文献   

Effect of body condition score and reuse of progesterone‐releasing intravaginal devices on conception rate following timed artificial insemination in Nelore cows          下载免费PDF全文

LL Pereira  AP Ferreira  WG Vale  LR Serique  KAL Neves  AC Morini  BM Monteiro  AHH Minervino 《Reproduction in domestic animals》2018,53(3):624-628

This study had the aim of investigating the efficiency of timed artificial insemination (TAI) through the progesterone‐releasing intravaginal device (PRID), used in new condition and for the second and third times in Nelore cows. The effects of device reuse and body condition score (BCS) on the conception rate (CR) were evaluated in 1,122 multiparous Nelore cows (mean BCS of 2.7 ± 0.4), which were randomly distributed into three groups that received new (n = 330), once (n = 439) and twice used (n = 353) PRID. Among the 1,122 females that underwent TAI, 573 became pregnant, thus representing an overall CR of 51.06%. Cows with BCS between 2.75 and 4.0 had greater (p < .0001) CR (69.75%) than cows with BSC of 2.0–2.5 (32.98%). It was observed that the CR through using PRID was 60.00%, 51.71% and 41.93% for new, once and twice used PRID, respectively, with difference between all groups (p < .0001). Under tropical conditions, animals with BCS greater than 2.5 had a higher CR, and the CR decreased proportionally with the number of times that the PRID had been used.  相似文献