异麦芽寡糖对肉仔鸡生产性能及肠道生理生化指标的影响

试验选用 90 0只雌雄各半 1日龄艾维茵肉鸡分 6组 ,每组 3重复 ,分别在饲料中添加异麦芽寡糖 (IOS) 0 %、0 .1%、0 .2 %和 0 .4 %、金霉素 15 0mg kg及金霉素 15 0mg kg+0 .4 %IOS ,研究了ISO对肉鸡的生产性能及肠道生理和生化指标的影响。IOS和金霉素处理均促进 0～ 3周肉鸡的采食 (P <0 .0 5 ) ,且IOS促进肉鸡采食的作用随添加量的提高而增强。IOS和金霉素处理降低 3周龄肉鸡回肠内容物中挥发性盐基氮含量 (P <0 .0 5 )和盲肠内容物中丙酸含量 (P <0 .0 1)。IOS处理增加 3周龄肉鸡空肠绒毛长度 (P <0 .0 1)。与添加 15 0mg kg金霉素组比较 ,IOS处理提高 3周龄肉鸡盲肠中丁酸含量 (P <0 .0 5 )和空肠绒毛长度 (P <0 .0 1) ,对其它各指标无影响。     

“金如意”山楂垄植早丰栽培技术研究

金如意山楂是2013开始年从山东省费县东蒙镇大门山在野生“小黄红子”单株发现、分离、培育，2019年12月经国家林业和草原局新品种审定并正式命名的山楂品种。该品种树姿直立，冠形卵圆形，树冠约为普通型的2/3；萌芽率高、形成中短枝能力强、成枝力中等；成花率高，花瓣白色、花药紫红色；座果率高；单果重12g，果皮金黄色、果肉浅黄色、味甜、适于鲜食；8月底~9月初成熟，属珍惜短枝型山楂品种。山地宽幅地块、泊地、易积水地块、瘠薄地块、土壤较黏重的地块起垄栽培。适宜自由纺锤形、高纺锤形、四主枝开心形。较抗白粉病；常发生白小食心虫、桃小食心虫、蚜虫等。     

Short catkin1, a novel mutant of Castanea mollissima, is associated with programmed cell death during chestnut staminate flower differentiation

The fact that male flowers far outnumber female flowers is a factor that limits nut yield in Chinese chestnut. A naturally occurring mutation of male catkins was found on a single branch of a Chinese chestnut tree in the mountains near Beijing, China. The mutation was named short catkin1 (sck1). The catkin length of sck1 was only 1/6 to 1/8 that of the wild-type male catkins on the same tree. The mutation was associated with a greater number of female flowers and increased yield. Observations on the development of male catkins with the sck1 phenotype showed that the distal part of the catkins aborted at the stage of chestnut staminate flower differentiation. Further research using transmission electron microscope analysis showed that the process of cell death in sck1 catkins had the typical characteristics of programmed cell death at the subcellular level, such as condensed chromatin, dissolved nucleolus, degraded karyoplasm, burst karyotheca, and disintegrated chloroplasts or mitochondria. Significantly, DNA laddering was detected in tissues of sck1 catkins. In conclusion, the results showed that sck1 was associated with PCD.     

Temperature and photoperiod control of morphology and flowering time in two greenhouse grown Hydrangea macrophylla cultivars

Knowledge of the factors involved, and tools to control morphology and flowering are important in intensive and cost-efficient greenhouse production. Hydrangea macrophylla is an important flowering pot plant in Norway and is produced year-around in greenhouses. Due to problems in scheduling, a study was conducted to compare floral transition and morphology of two commercially important cultivars of Hydrangea (‘Early Blue’ and ‘Schneeball’) under different flower initiating treatments in growth chambers. Plants were grown with high pressure sodium lamps (HPS) at moderate temperature (17 °C) (MT) and high (24 °C) temperature. At high temperature, the effect of (1) irradiance under long day conditions (16 h lighting with 70 or 200 μmol m⁻² s⁻¹), and (2) short day (8 h lighting) was investigated. The short day treatment had similar light integral as the low irradiance long day treatment (SD: 8 h × 140 μmol m⁻² s⁻¹ and LD: 16 h × 70 μmol m⁻² s⁻¹ = 4.0 mol m⁻² d⁻¹). The intention was to test the effect of irradiance and SD on flower transition and morphology under high temperatures. The results clearly showed that MT is the strongest signal for floral transition. MT resulted in a rapid floral transition of the terminal buds and lateral flower buds. A short forcing period was required and the plants became short and compact without any use of chemical growth retardants. At high temperatures only SD had a promotive effect on flower transition and the response was found to be stronger in ‘Schneeball’ than ‘Early Blue’. In general, all the treatments under high temperatures required a long forcing time and the plants tended to be very tall with a low number of lateral flower buds.     

A new lean no time test baking method with improved discriminating power

In response to customer concerns related to gluten strength in commercial baking, the Canadian Grain Commission assessed whether the Canadian Short Process (CSP) test bake method was generating useful data related to intrinsic strength of wheat varieties. Assessment of CSP loaf volume data for Canadian variety trials spanning 2003 to 2013 showed very little correlation with dough strength parameters as measured by farinograph and extensigraph. A lean no time (LNT) test baking method was developed that can better discriminate genotypes and provide objective indicators of the effect of intrinsic dough strength on baking quality. From early method development, through method validation and verification using diverse sets of samples targeting different Canadian wheat classes and grown in three different crop years, results showed the LNT method to be more discriminating and easily adopted by other laboratories. In 2015, the LNT method was adopted as the method of choice in future Canadian variety registration trials. The LNT method is fast, simple and well-suited to high throughput test baking conditions encountered in the evaluation of large numbers of breeder lines. A new objective parameter, loaf top ratio, was also introduced and found to correlate well with dough strength and dough handling properties.     

温度对粳稻光温敏感雄性核不育系育性影响

粳稻光温敏感雄性核不育系(简称“二系不育系”)的繁种是二系杂交稻繁殖的重要环节,影响不育系育性的两大因素为光周期与温度,光周期是基本不变的因素,温度在气候环境影响下为可变因素。通过6个不同类型的不育系在上海地区晚播和海南短日照下,观察不同温度对各不育系的育性影响,了解不育系育性随温度的变化规律与发展趋势,确定二系不育系的最佳繁种地点、时间、方法,为二系杂粳组合在生产上应用提供繁种科学依据。     

短雄花序板栗芽变的AFLP分析

 利用AFLP分子标记技术对板栗短雄花序芽变及其母株进行了初步研究, 72种引物组合共产生5 129条清晰谱带, 多态性位点53个, 多态性2.05% , 相似性系数0.9897, 差异片段主要集中于300～900 bp之间。研究表明短雄花序芽变和对照个体之间变异与遗传物质的改变相关, 其中一些可能与雄花序变短的基因有关。     

甘露寡糖对动物肠道免疫的影响及其在动物生产中的应用研究进展

甘露寡糖(MOS)可以提高肠道益生菌竞争优势,增加肠黏膜蛋白和紧密连接蛋白分泌量,促进益生菌代谢产物短链脂肪酸生成,抑制核因子κB通路,催化雷帕霉素靶蛋白表达,降低下游促炎因子合成释放,调控肠道免疫机能.本文综述了MOS对动物肠道免疫的影响及其在动物生产方面的应用研究进展,为其提高畜禽生产性能的应用及研究提供参考.     

板栗雄花序萃取物抗氧化及抑菌效果

【目的】研究板栗雄花序不同萃取物的抗氧化及抑菌效果,为其进一步开发与利用提供基础。【方法】用不同极性溶剂对板栗雄花序乙醇浸膏进行萃取分离,得到石油醚萃取物、二氯甲烷萃取物、乙酸乙酯萃取物、正丁醇萃取物4个部分;并采用1,1－二苯基－2－三硝基苯肼( DPPH·)自由基清除和硫代巴比妥酸法测定醇提物及不同萃取物的抗氧化能力,以滤纸片琼脂扩散法和共培养测定抗菌活性。利用高效液相色谱法( HPLC)和核磁共振波谱法(NMR)鉴定出板栗雄花序中的鞣花酸(EA),并对其进行初步定量与结构分析。【结果】1)通过系统提取法得到板栗雄花序醇提物提取率为16.6%,其他4种萃取物提取率在2.6%～26.2%,其中乙酸乙酯萃取物提取率最高。2)板栗雄花序醇提物及不同萃取物对 DPPH·自由基、卵黄脂质过氧化物都有一定的清除能力,其中乙酸乙酯萃取浓度为0.01 mg·mL －1时,对 DPPH·清除率达到94.4%,对卵黄脂质过氧化物的清除率为95.69%,与同浓度的抗坏血酸(Vc)和2,6－二叔丁基－4－甲基苯酚(BHT)清除率相当。3)板栗雄花序醇提物对12种细菌都有一定程度的抑制效果,在不同萃取物中乙酸乙酯萃取物抑菌效果最好,对大肠杆菌的最低抑菌浓度为0.98 mg· mL －1,最低杀菌浓度为1.96 mg·mL －1。板栗雄花序样品中有游离鞣花酸,含量为2.267 mg·g －1。【结论】板栗雄花序中含有较多抗氧化和抑菌的活性物质,其醇提物及不同极性萃取物的抗氧化能力存在较大差异,乙酸乙酯萃取物抗氧化活性较高,对清除 DPPH·自由基和脂质过氧化物都有较好的效果。各个萃取物对 G +菌和 G －菌都有一定作用,其中乙酸乙酯萃取相的抑菌活性最好。     

Biomass production physiology and soil carbon dynamics in short-rotation-grown Populus deltoides and P. deltoides × P. nigra hybrids

Fast-growing woody species grown in dense, short-rotation plantations on land previously in agriculture offer potential economic benefits in products such as engineered construction material, boiler fuel, non-food-based biofuel feed stocks and other carbon (C)-based products and credits. However, information on the effects on major C pools of short-rotation culture is relatively sparse. In this study, Populus deltoides and P. deltoides × P. nigra hybrid clones were grown for 5 years at 1 m × 1 m spacing in plantations on a former pasture of high native fertility in the Missouri River floodplain in the lower Midwest U.S.A. Above- and below-ground biomass production, leaf area-based production efficiency, photosynthetic attributes and soil C dynamics were studied.