不同激素对碧云茶树丛生芽增殖培养的影响实验

为了获得碧云茶树的组培技术,加快其优良品种繁殖速度,2010～2011年进行了不同浓度的细胞分裂素6-BA和生长素NAA对碧云茶树丛生芽增殖培养的影响。结果表明,以MS为基本培养基,当6-BA为2.0 mg/L,NAA为0.2 mg/L时,对碧云茶树芽的诱导和增殖最有利,增殖率可达2.84;其中NAA差异不显著,6-BA差异显著。     

黑纹粉蝶在室外养虫网室中连续繁殖的滞育变化

系统观察了黑纹粉蝶PierismeleteMenetries在室外养虫网室中8个世代的滞育变化。结果表明：？夏季高温和长日照明显抑制了滞育的发生，在日平均气温为27℃的6月份，仅有15．9％的个体进入夏季滞育，在日平均气温29．5℃的7月份，夏季滞育则完全消失。！春季逐渐上升的日长（13h24min～14h21min）配合较温暖的气温（日平均19．1℃），诱导了99．6％的个体进入夏季滞育；秋后逐渐缩短的日长（11h53min～11h20min）配合较低的气温（日平均16．5℃），诱导了100％个体进入越冬滞育。秋季逐渐缩短的日长（14h12min～11h53min）配合较高的气温（日平均27．7℃）和较温暖的气温（日平均22．9℃和18．7℃），能满足大部分个体非滞育的发育。试验结果亦表明，黑纹粉蝶具有在夏季繁殖的潜在能力，虽然这种能力在自然条件下没有表现出来。文章最后讨论了该虫夏季带育诱导的光、温机制的适应意义。     

Transport of nutrients and electrolytes across the intestinal wall in pigs

In recent years, intestinal transport processes have been studied in detail regarding both, functional and structural aspects. For monosaccharides different systems have been demonstrated for apical uptake: this includes the high-affinity SGLT1 as a distinct d-glucose system and GLUT5 for fructose. Specifically in pigs a low affinity, high-capacity system for d-glucose and d-mannose with no preference for Na⁺ over K⁺ and a very low affinity system are suggested as further uptake systems. As in other species, basolateral extrusion is mediated by GLUT2. The distributions of monosaccharide transport along the gastrointestinal axis as well as the potential role of paracellular monosaccharide absorption have not yet been clarified.

Amino acids can principally be absorbed by the paracellular and transcellular pathway whereas transcellular transport can either be mediated by facilitated diffusion or secondary active Na⁺-coupled transport. This includes different transport systems for neutral, anionic and cationic acids. In addition, the presence of the di-/tripeptides transport system PEPT1 which depends on an inwardly directed H⁺-gradient has also been confirmed for the pig small intestine, its quantitative proportion is still under debate.

Short chain fatty acids (SCFA) are the major end products of microbial carbohydrate fermentation which occurs along the gastrointestinal tract with the highest production rates in the large intestines. At least two uptake mechanisms have to be assumed, i.e., non-ionic diffusion and anionic exchange via SCFA⁻/HCO₃⁻-exchange. Controversial views still exist to what extent SCFA are metabolized within the epithelial tissue.

Segmental differences between small and large intestines have been demonstrated for Na⁺ absorption. Whereas in the small intestines the major part of Na⁺ absorption is mediated by coupled nutrient transport systems, aldosterone sensitive Na⁺ channels and Na⁺/H⁺-exchange are the dominant mechanisms in the hindgut. For Cl⁻ paracellular transport and anionic Cl⁻/HCO₃⁻-exchange are the major absorptive mechanisms. Cl⁻ secretion is mediated by apical channels which may be activated by toxins of different origin. Different types of Cl⁻ channels have been identified, such as Cystic Fibrosis Transmembrane Regulator (CFTR), Ca-activated Cl⁻ channels (CLCA) and Outwardly Rectifying Cl⁻ Channels (ORCC). Whereas CFTR has clearly been shown for jejunal and colonic epithelial and goblet cells controversy still exists on the relevance of CLCA and ORCC in pigs.

For Ca²⁺ there is evidence that both recently published channels TRPV5 and TRPV6 are also expressed in pig intestinal tissues, however, this has not yet been shown on protein level. From several functional approaches it was demonstrated that phosphate uptake can be mediated by both, a Na⁺-dependent transcellular component and paracellularly. On a molecular basis it is uncertain whether the transport protein of transcellular mechanism belongs to the NaPi-IIb cotransporter family.     

家蝇抗菌肽的研究进展马红霞

从家蝇抗菌肽的分类、结构特点、作用机理、诱变、活性检验以及分子生物学研究等方面介绍了家蝇抗菌肽的研究进展。家蝇抗菌肽独特的作用机理、成熟的诱导、分离纯化技术及其相关基因的克隆、表达等研究成果均为对家蝇抗菌肽进行更深入的研究奠定了基础。采用分子生物学技术有望筛选并制备大量的高效家蝇抗菌肽。     

三倍体梨新品种‘龙园洋红’

 龙园洋红’是三倍体梨新品种, 属短枝型, 亲本为56-5-20和乔玛, 抗寒力强, 平均单果质量185.5 g, 最大可达650.6 g, 果实为不规则长椭圆形, 果型指数1.13。果皮底色黄, 有红晕。果肉白色,细软多汁, 可溶性固形物16.05% , 可溶性糖11.68%。可滴定酸0.81% , 果实9月15日左右成熟, 风味酸甜适度、有香味。     

美国白蛾生物学上的几个重要特性

本文对青岛市美国白蛾Hyphandria cunez种群的几个重要生物学特性进行了调查，获得了如下有意义的结果。（1）在生态光周期范围内，该虫显示了一个典型的长日照型昆虫，临界日长为14h 30min。然而在全光条件下，有41.2％的个体滞育；在全暗条件下则有83．7％的个体发育。（2）第1代蛹在自然条件下羽化的结果表明，部分个体的蛹期显著延长，呈现了夏季滞育。（3）滞育蛹置于25℃，LD16：8下滞育能够解除，但死亡率极高。（4）雄虫前翅黑斑的出现是由光周期控制的，只有在短日照下诱导的滞育蛹，滞育解除后羽化出来的雄虫才会出现黑斑。     

多效唑对八仙花组培苗营养生长及成花的影响

以八仙花1、2 a生组织培养苗为试验对象,研究了多效唑不同浓度、不同施药时间、不同施药次数对八仙花组培苗促成栽培中其植株营养生长及成花的影响.结果表明:施用浓度和时间是多效唑抑制八仙花组培苗植株营养生长促进其生殖生长的关键,7月中旬以浓度100～150 mg/L的多效唑溶液对八仙花1、2 a生组织培养苗进行叶面喷施,最有利于其花芽分化,成花率高,且从株型、花形花色等各项指标综合考虑,多效唑对促进八仙花2a生组培苗成花效果更显著.施药次数也影响八仙花组培苗营养生长和成花,连续施药3次对抑制其营养生长促进成花效果最佳.     

多年生黑麦草高频再生体系的建立及优化

从外植体预处理方式、基本培养基、激素浓度等方面着手,对多年生黑麦草愈伤组织诱导、继代、不定芽分化及再生过程中的影响因素进行了研究,提高了再生频率。结果如下：切取胚端半粒种子,经75%乙醇处理1min,0.1%HgCl处理15min,在经无菌水清洗4～6次后接种方式较好;愈伤组织诱导培养基以MS＋2,4—D 8.0 mg/L（或另添加甘露醇25 g/L）为佳;愈伤组织接种于MS＋2,4—D 8.0mg/L＋甘露醇25 g/L上进行1～2次继代后于NB＋6—BA2.0 mg/L上进行分化;不定芽转接至MS＋6—BA2.0 mg/L上进行扩繁或于1/2MS＋NAA0.5mg/L＋IAA0.5mg/L上进行生根。     

蝴蝶兰花芽诱导过程中碳水化合物在叶与腋芽中的分配变化

 研究了粉色蝴蝶兰（KM 833）在两个不同条件下处理（处理组：人工气候箱日/夜温25℃/20℃；对照组：温室大棚生长条件）过程中叶片和腋芽中碳水化合物在叶与腋芽中的分配变化。结果发现对照的蝴蝶兰新叶开始时面积增长较快，但最后的叶面积的大小基本相同，处理组的单位叶面积干样质量在15 d后超过对照组；处理组蝴蝶兰叶片还原糖含量在20 d达到1个小高峰后下降，在30 d后开始急剧上升,至50 d达到最大值(31.08 mg·g^-1DM)，对照组的蝴蝶兰叶片还原糖含量在整个试验期间则较为恒定且缓慢地增长，腋芽中的还原糖含量则随时间而下降；两种处理蝴蝶兰叶片的可溶性糖和淀粉含量均随着时间的进程而逐步升高，处理组的蝴蝶兰腋芽中的可溶性糖和淀粉含量则在处理15 d内有个快速增加后缓慢下降，对照组腋芽的三类碳水化合物在处理期间处于上升趋势。无论在叶还是腋芽中,诱导组的碳水化合物含量均高于对照组。     

豫西脂尾羊排卵规律及胚胎生长发育规律的研究

豫西脂尾羊以单侧卵巢排卵为主，单侧卵巢排卵母羊百分比为98．18％，其中左侧为34．35％，右侧为63．64％。右侧卵巢排卵母羊数极显著多于左侧卵巢排卵的母羊数（P＜0．01）。总排卵率及排单卵、双卵和三卵的百分率分别为110．91％、90．91％、7．27％和1．82％。其胚胎长度增长以胎儿中期生长速度最快，而体重增长自进入胎儿中期以后一直比较旺盛。研究结果表明，豫西脂尾羊产羔率低的直接原因是排卵率低，主要是排双卵和三卵的比例低。根据豫西脂尾羊排卵及胚胎生长发育特点，就如何提高其繁殖率问题提出了具体建议和措施。