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11种杀菌剂对马铃薯软腐病的防治效果 总被引：1，自引：0，他引：1
由果胶杆菌属细菌Pectobacterium spp.引起的软腐病是世界范围内马铃薯生产上重要的细菌性病害之一。本研究分别采用碟片法和生长速率法探究了11种常用的杀菌剂对胡萝卜果胶杆菌胡萝卜亚种菌株Pcc20181的离体抑菌效果; 采用马铃薯半薯接种法评价了供试杀菌剂对马铃薯软腐病的防控效果。碟片法和生长速率法测定结果均显示:11种供试杀菌剂中72%农用硫酸链霉素SP、0.3%四霉素AS和3%噻霉酮WP离体抑菌效果最好, 抑菌圈直径介于0.13~1.47 cm, EC50介于1.695~44.363 mg/L; 新鲜半薯接种法测定结果表明, 11种供试杀菌剂中有8种对软腐病均有控病效果, 防效为33.33~92.50%。其中, 3%噻霉酮WP对马铃薯软腐病的防效最高为92.50%, 随后依次为72%农用硫酸链霉素SP （89.76%）、20%叶枯唑WP （58.81%）、0.3%四霉素AS （51.60%）。综合评价, 3%噻霉酮WP、20%叶枯唑WP和0.3%四霉素AS对马铃薯软腐病具有较好的防控效果。 相似文献
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砧木和接穗苗龄对顶插接法西瓜嫁接苗生长发育的影响 总被引：1，自引：0，他引：1
采用二因素完全随机设计,研究不同砧木和接穗苗龄对顶插接法西瓜嫁接苗成活率、嫁接苗形态指标、叶绿素含量及根系活力的影响。结果发现,随着砧木苗龄的增大,嫁接苗的根系活力均呈先增加后降低的趋势,叶片数、接穗干质量、嫁接成活率、茎粗、叶片叶绿素含量的变化各异;随着接穗苗龄的增大,嫁接苗的嫁接成活率、叶片数、茎粗、接穗干质量、叶片叶绿素含量、根系活力均表现为先增高后降低的趋势。采用隶属函数法综合评价西瓜嫁接苗的质量,发现接穗苗龄9~13d、砧木苗龄11~15 d的西瓜嫁接苗隶属函数值较大,是适合西瓜顶插接法的接穗和砧木最佳苗龄时期。 相似文献
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试验旨在通过探讨不同添加剂对花生秧青贮品质的影响,为提高花生秧单独青贮效果提供理论依据和技术支持。青贮试验包括4个处理组,即对照组(不添加任何添加剂)、甲酸处理组、纤维素酶处理组和绿汁发酵液处理组,每个处理组3个重复,贮存40 d后开包检测。结果显示,纤维素酶组感官评分最高,等级为良,其他3组均为一般;与对照组相比,绿汁发酵液组p H值极显著降低(P0.01),甲酸组和纤维素酶组氨氮/总氮显著降低(P0.05),甲酸组乳酸含量极显著提高(P0.01);各处理组青贮料的干物质、粗蛋白、中性洗涤纤维和酸性洗涤纤维含量均无显著差异(P0.05)。在试验条件下,综合感官评定及实验室测定结果,以纤维素酶组青贮花生秧品质最佳。 相似文献
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梁欢 《北方牧业(奶牛)》2007,(5):30-30
在炎热季节，奶牛的食欲下降，应当提高日粮中的总可消化养分值，大部分奶牛会发生不同程度的热应激反应，严重影响奶牛生产性能和健康，因而受到奶牛业界的普遍关注和重视，应当提高日粮中的总可消化养分值。许多研究发现，在日粮中加入某些饲料添加剂，可以缓解热应激对奶牛的不良影响。下面进行简要介绍，希望对广大奶牛养殖业户有所裨益。 相似文献
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张丽李川邱清华张健陈薪芋许兰娇赵向辉李艳娇梁欢欧阳克蕙 《动物营养学报》2023,(1):450-459
The aim of this experiment was to investigate the changes of rumen microbiota density and physicochemical properties at different pH. Five Holstein cows in dry milk period were selected as rumen fluid donors. Using in vitro method, five treatments were set according to the criteria of rumen acidosis, and the pH of culture medium was 6.5, 5.8, 5.5, 5.2 and 5.0, respectively, with five replicates in each treatment. After three hours of incubation, the changes of rumen microbiota density and physicochemical properties were measured. The results showed as follows: 1) with the decrease of pH, the rumen microbiota density showed a fluctuation change of first decreasing, then increasing and then decreasing, and the microbiota density in pH 5.8 treatment was significantly lower than that in pH 6.5 treatment (P<0.05). When pH was 5.2, the rumen microbiota density was the highest, which was significantly higher than that in the other treatments (P<0.05). 2) With the decrease of pH, the intracellular H+-ATPase activity in rumen microbiota was firstly increased and then decreased, but there was no significant difference among all treatments (P>0.05). 3) The intracellular ATP content in rumen microbiota was not significantly affected by different pH treatments (P>0.05). 4) With the decrease of pH, the intracellular protein content in rumen microbiota was gradually increased (P<0.05). 5) With the decrease of pH, the intracellular pH (pHi) and cellular transmembrane pH difference (ΔpH) in rumen microbiota were firstly increased and then decreased, and the pHi and ΔpH in pH 5.5 and 5.2 treatments were significantly higher than those in the other three treatments (P<0.05). 6) With the decrease of pH, the cell membrane permeability of rumen microbiota was gradually increased, except for pH 5.8 treatment, the other treatments were significantly higher than pH 6.5 treatment (P<0.05). In conclusion, the rumen microbiota can increase the intracellular H+-ATPase activity and protein content, consume ATP, and change pHi and ΔpH in response to external pH decline. When pH decreases to 5.5, the membrane permeability and pHi of rumen microbiota increase significantly, indicating that they are running to be subjected to more serious acid stress. The density of rumen microbiota fluctuates with the decrease of pH, and when pH decreases to 5.2, the density of rumen microbiota is the highest. © 2023 Authors. All rights reserved. 相似文献
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近年来，随着奶牛生产性能的不断提高，对奶牛饲料的能量水平要求越来越高。而通过提高奶牛饲料的精粗比和添加油脂来满足能量的需要都有其难以克服的缺点。提高精粗比易引起纤维素消化率降低、乳脂下降、瘤胃功能紊乱及酮病；在奶牛日粮中直接添加脂肪会妨碍瘤胃微生物的活动，降低纤维消化率。而脂肪酸钙保护性脂肪由于其为固体粉末，在瘤胃中不溶解，只在真胃和小肠中才被水解，既可避免对瘤胃微生物的影响，[第一段] 相似文献
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梁欢 《北方牧业(奶牛)》2006,(1):26-28
根据矿物质占动物体比例的大小，分为常量元素和微量元素。常量元素是指元素占动物体比例在0．01％以上；反之则为微量元素。现已确认有20多种矿物质元素是乳牛所必需的。在常量元素中有钙、磷、钠、氯、镁、钾、硫等；微量元素中有铜、铁、锌、锰、钴、碘、硒等下面就一些重要的矿物质元素加以分别说明。 相似文献
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