低聚糖对雏鸡大肠粪便NH3-N含量及肠道菌群的影响

试验选取1日龄罗曼蛋公雏250只，随机分为5组，试验组饲料或饮水中分别添加海藻糖(500mg／kg)、海藻胶(600mg／kg)、大豆寡糖(500mg／kg)、圆葱寡糖(500mg/d)。结果表明，四种低聚糖均可促进肠道乳酸菌及双歧杆菌的生长繁殖，对魏氏梭菌的生长呈现抑制作用。海藻糖、海藻胶对降低大肠粪便NH3—N含量效果不显著(P＞0．05)，而大豆寡糖效果显著(P＜0．05)，圆葱寡糖效果极显著(P＜0.01)。     

玉米的不同加工处理对绵羊瘤胃内pH值、NH3-N和VFA浓度的影响

选用 4头装有永久性瘤胃瘘管的内蒙古半细毛羯羊 ,饲喂 4种含有不同加工处理玉米的日粮 ,在精粗比为 30∶70 ,饲养水平为 1.3MJ日粮条件下采用 4× 4拉丁方试验设计 ,对瘤胃pH值、NH3 -N和VFA浓度进行了测定 ,并研究了它们的动态变化规律。实验结果表明 :各处理组对瘤胃内 pH值影响较小 (P >0 .0 5 ) ;不同处理组与对照组比都有降低瘤胃NH3 -N浓度的趋势 ,但差异不显著 (P >0 .0 5 ) ;对VFA浓度也有一定影响 ,但各组间差异不显著 (P >0 .0 5 )。各处理组间乙酸 /丙酸基本接近 ,均属丙酸 /乙酸发酵类型     

TheEstimationofStemTaperCurvefromtheRadialInformationatThreeLocationsontheStem

该文探讨了不用编制削度表直接建立高精度立木干曲线的方法．当采用干曲线是３次多项式时，通常根据１０分法测定树干各部位直径，用最小二乘法求出该方程式的参数．从数学角度，只要知道树干任意３个部位的直径，就可以用最小二乘法或联立方程式求解干曲线参数．本文以樟子松为例，探讨用树干哪３个部位直径拟合的干曲线最接近实际干曲线，为建立立木干曲线提供有效方法．利用９个部位半径（方法Ⅰ）和利用其中３个部位半径（方法Ⅱ，２８种组合）分别拟合干曲线，结果表明方法Ⅱ的６种半径组合的精度良好，其中的３种组合，（ｒ１．３，ｒ０．３，ｒ０．７），（ｒ１．３，ｒ０．４，ｒ０．７）和（ｒ１．３，ｒ０．４，ｒ０．８）是拟合现实干曲线的有效方法．     

立筒仓磷化氢环流熏蒸试验

文章主要探讨了生产中利用磷化氢环流熏蒸技术对立筒库群进行熏蒸的方法和杀虫效果。试验结果表明，该项技术对于立筒仓这类深粮层仓型熏蒸杀虫有很好的效果。对仓内的主要害虫有较好的杀死作用；但由于仓房气密性、环流方法和设备性能等因素的影响，操作不当就不能彻底杀死某些局部虫害或不久又再次发生害虫危害，影响整体熏蒸效果。     

LRH─A3、hCG和PMSG对体外培养条件下牦牛垂体组织LH和FSH分泌的调节

促卵泡素３号（ＬＲＨ－Ａ３）、人绒毛膜促性腺激素（ｈＣＧ）和孕马血清促性腺激素（ＰＭＳＧ）等３种外源性激素均可增加体外培养条件下牦牛垂体组织分泌ＬＨ和ＦＳＨ的能力。培养液中ＬＨ和ＦＳＨ含量与加入的ＬＲＨ－Ａ３量呈正相关，与加入的ＰＭＳＧ和ｈＣＧ的量无显著关系     

The intravenous bile Acid loading test in the goat: determination of a procedural protocol and reference values

An intravenous bile acid loading test was performed on 16 goats using various dosages and sampling protocols. A recently developed enzymatic bile acid assay provided an economical and technologically simple method for bile acid analysis. Intravenous injection of bile salts into goats was well tolerated. Clearance times were rapid. A protocol for performance of the test was suggested and a practical reference range for T 1/2 clearance of 4+/-1 minute was determined. Further investigations of this test in the assessment of liver function in the ruminant appear warranted.     

Dynamics ofRhizoctonia solani (black scurf) in successive potato crops

The position of plants withRhizoctonia solani sclerotia (black scurf) on progeny tubers was mapped for an experimental field at Haren where potatoes were grown continuously and in rotation with other crops for five successive years, and for another field at Borgercompagnie with a 12 frequency of potatoes during three potato crops. Initially, the distribution of plants with black scurf on both fields was rather dense and homogeneous. In the following years the distribution became heterogeneous and patchy. The local decline ofR. solani AG 3 (the common potato pathogen) in Haren was apparently caused by an unknown factor selectively suppressingR. solani AG 3, while simultaneouslyR. solani AG 5 increased in mass. This AG 5 type proved to be an inferior competitor of AG 3 on the potato plant in a laboratory experiment. The specificR. solani antagonistVerticillium biguttatum did not play a role. A similar factor could have reduced the formation of black scurf in the experimental field at Borgercompagnie, whereV. biguttatum was also too infrequent to account for the decline.R. solani AG 5 was not present here and could not indicate the presence of a selective factor against AG 3.     

Contribution to the taxonomy and pathogenicity of fungicolous Verticillium species. II. Pathogenicity

In recent years in the Netherlands a second mushroom species,Agaricus bitorquis, which prefers higher temperatures thanA. bisporus and is less susceptible to certain diseases, is often commercially grown.Verticillium fungicola var.fungicola, the causal agent of dry bubble, is responsible for considerable damage in crops ofA. bisporus. InA. bitorquis, however, dry bubble has hardly been noticed, but brown spots due toV. fungicola var.aleophilum resulted in inferior mushroom quality. The latter variety also caused brown spots ina. bisporus, but to a minor degree. In variety Les Miz 60 ofA. bisporus, however, it also induced fruit-body deformation in a way different from dry bubble. Verticillium psalliotae, isolated fromA. bitorquis in England, induced more confluent brown spots inA. bitorquis. In the netherlands, where moreA. bitorquis is grown than in other countries,V. psalliotae has not yet been encountered in crops ofA. bitorquis. V. psalliotae, which has a high temperature optimum for mycelial growth, likeV. fungicola var.aleophilum andA. bitorquis, did not infectA. bisporus in our trials.Artificial infection ofA. bisporus orA. bitorquis could not be accomplished with the following related and/or fungicolous fungi:Verticillium lamellicola, V. fungicola var.flavidum, V. biguttatum, Nectriopsis tubariicola, Acremonium crotocinigenum andAphanocladium album.Samenvatting Vooral in Nederland wordt sinds een aantal jaren naastAgaricus bisporus ook de warmteminnende champignonsoortAgaricus bitorquis geteeld, die minder vatbaar is voor bepaalde ziekten. TerwijlVerticillium fungicola varfungicola in de teelt vanA. bisporus droge mollen en daardoor veel schade veroorzaakt, komen in de teelt vanA. bitorquis geen droge mollen voor maar wel bruine vlekken, die tot kwaliteitsverlies en dus schade leiden. De vlekken bleken veroorzaakt te worden doorV. fungicola var.aleophilum. Deze schimmel veroorzaakte ook inA. bisporus bruine vlekken, hoewel in minder ernstige mate, maar in het ras Les Miz 60 vanA. bisporus bovendien misvormde champignons, die wel op droge mollen leken, maar daaraan niet gelijk waren.OokV. psalliotae, in Engeland geïsoleerd vanA. bitorquis met vlekken, veroorzaakte wat meer samenvloeiende, bruine vlekken inA. bitorquis. In Nederland, waar meerA. bitorquis geteeld wordt dan in andere landen, isV. psalliotae nog niet aangetroffen in teelten vanA. bitorquis. InA. bisporus kon geen kunstmatige infectie worden verkregen metV. psalliotae, die net alsV. fungicola var.aleophilum enA. bitorquis warmteminnend genoemd zou kunnen worden.Met de volgendeVerticillium-achtige of van paddestoelen geïsoleerde schimmels kon evenmin op kunstmatige wijze een infectie worden opgeroepen inA. bisporus ofA. bitorquis: Verticillium lamellicola, V. fungicola var.flavidum, V. biguttatum, Nectriopsis tubariicola, Acremonium crotocinigenum enAphanocladium album.     

香蕉ACC氧化酶基因(MAO3)的克隆及其表达特性分析

 根据同源扩增得到香蕉(Musa acuminata) ACC氧化酶基因(MAO3) 的核心部分, 再通过3'和5'RACE扩增上、下游序列以及Genome-Walker的方法得到启动子部分, 共获得3 718 bp长度的序列。将所得结果进行聚类分析, 发现香蕉中ACC氧化酶的氨基酸序列非常保守, 各序列间的同一性高达99% ,与单子叶植物和双子叶植物中ACC氧化酶的氨基酸序列的同源性在66.7%～71.8%之间。组织原位杂交试验表明MAO3基因的表达具有组织特异性, 初步认为是在韧皮部筛管组织中特异表达。运用实时荧光定量PCR技术, 实时监测到了MAO3基因和香蕉乙烯受体基因ERS2受机械伤诱导的定量变化。     

硝酸钙和IAA对温州蜜柑果实钙含量及其品质的影响

在花期、花后1周、3周、采前2周对龟井蜜柑进行Ca(NO3)2、IAA和IAA+Ca(NO3)2喷布处理,同时测定了不同发育时期各处理果实钙含量及其采后果实的主要品质,并与采后浸钙处理和完熟采收果实品质进行了对比分析,结果表明:1)各处理的果皮钙含量在花后51d和112d均有所提高,但此期整个果实钙含量并无显著性差异,采收时各处理整个果实和果肉钙含量均显著高于对照;2)采收时各处理果实的可溶性固形物和可滴定酸均显著低于对照,可溶性糖、单果重、果皮色差值和相对电导率与对照无显著性差异,各处理糖酸比显著高于对照;3)采后30d时IAA+Ca(NO3)2喷布和采后浸钙处理果实的维生素C及完熟采收果实的可溶性固形物和可溶性糖均显著高于对照和其他处理。