蜗牛消化酶提取河蟹微孢子虫基因组反应条件的优化

PCR是目前能够特异地检测河蟹微孢子虫的最灵敏的方法。河蟹微孢子虫孢子壁坚厚不易破碎,对许多化学物质有很强的抵抗性,常规的核酸抽提方法效果不够理想。本文通过对比PCR的结果,研究蜗牛消化酶对DNA抽提效果的影响,确定了酶作用的最佳反应条件,提高了PCR检测河蟹微孢子虫的灵敏性。结果显示:蜗牛消化酶提取微孢子虫DNA的酶促反应温度为37℃,底物浓度为20 mg,酶的使用浓度为酶/底物重量比400 mg/g,酶促反应时间为4 h。实验表明,使用蜗牛消化酶处理样品,有助于更加灵敏地检测出微孢子虫。该研究结果将有助于提高河蟹微孢子虫病的检验检测能力,对河蟹微孢子虫的检疫和防治具有积极意义。     

Growth performance and whole‐body composition of yellow catfish (Pelteobagrus fulvidraco Richardson) under feeding restriction

Fish growth is an important index in aquaculture practice. However, the effect of growth under restricted feeding on quality of fish grown to the same size remains poorly unknown. In this study, yellow catfish were reared by feeding them at three different feeding rates such as low (FR‐L group), medium (FR‐M group) and high (apparent satiation) ration levels for 82, 58 and 34 days to reach the same size, respectively. After this period, the growth performance, whole‐body amino acid composition and fatty acid profile of the fish were evaluated. Feeding restriction led to significant decreases in specific growth rate and feed conversion efficiency. Significant increases in dry matter, protein and energy contents were observed in fish under both restricted feeding treatments. FR‐L‐treated fish had significantly lower whole‐body essential amino acid contents, and significantly higher Ala and non‐essential amino acid contents compared to fish fed to satiation. Fish in restricted feeding treatments had significantly higher n‐3 PUFA and n‐3/n‐6 ratio compared to the fish fed to satiation. The present results indicate that from a quality perspective, there are certain advantages in improvement of whole‐body composition and enrichment of n‐3 PUFA associated with the restricted feeding of yellow catfish at slow growth rate.     

转基因抗虫棉中棉所76高效制种技术规程

总结了优质抗虫棉中棉所76高效制种技术，包括：制种田的选择、前期准备、亲本种植与管理、制种程序及注意事项等关键技术。     

Soil water response to precipitation in different microtopographies on the semi-arid Loess Plateau,China

Soil water is an important factor restricting afforestation on the semi-arid Loess Plateau.The microtopography of the loess slope has changed the distribution pattern of soil water on the slope.To improve water utilization efficiency and optimize afforestation configuration patterns,the relationship between soil water and precipitation at micro-topographic scale must be studied.We used time series analysis to study the temporal variation of soil water and its response to precipitation in four kinds of micro-topographies and undisturbed slope on loess slopes.Micro-topographies significantly influenced soil water distribution and dynamics on the slopes.Soil water stored in the platform,sinkhole,and ephemeral gully influenced subsequent soil water for 4 weeks,whereas soil water stored in the scarp and undisturbed slope could influence soil water for 2 weeks.It took 12 weeks,10 weeks,18 weeks,6 weeks,and 12 weeks for precipitation to reach the deeper soil layer in the platform,sinkhole,scarp,ephemeral gully,and undisturbed slope,respectively.These soil water characteristics in different micro-topographies are vital factors that should be taken into consideration when undertaking afforestation on the Loess Plateau.     

贝母属植物叶绿体基因组候选SNP位点应用分析

贝母属植物是中国中药材的宝库,由于形态上难以区分,在民间应用、临床应用和中药市场中还存在混淆应用、以次充好的现象,急需开发基于新型分子标记位点的精准检测方法。本研究应用多重序列比对、SNP筛选等生物信息学分析手段,对贝母属15种植物28条叶绿体基因组序列进行分析。结果发现,贝母属叶绿体基因组DNA同源性达97.22%,通过分析共发现SNP位点5879个,其中川贝母类鉴别候选位点71个,川贝母鉴别候选位点4个,瓦布贝母鉴别候选位点37个,太白贝母鉴别候选位点147个,浙贝母鉴别候选位点91个,湖北贝母鉴别候选位点271个,平贝母鉴别候选位点1393个,伊贝母鉴别候选位点89个。本研究还对SNP位点在精准鉴定、精确定量应用方面进行了讨论,可为川贝母中药资源鉴定提供技术支撑。     

薏苡紫色柱头性状的遗传分析

为研究薏苡紫色柱头性状的遗传规律,利用4份材料做亲本构建4个杂交组合,观察并记录其F 1、F 2植株的性状特征和分离比例。结果显示,紫色柱头相对于白色为显性,各F 2群体植株的柱头颜色分离比皆符合3∶1比例,说明紫色柱头是由1对显性等位基因控制。     

不同土壤条件下氮肥处理对小麦产量及品质的影响

为探讨不同土壤条件下氮肥处理对小麦产量及品质的影响,采用盆栽试验,以Egypt1和津强7号为供试材料,研究不同土壤条件下氮肥处理对小麦产量及品质的影响。试验设黑土、潮土2种土壤类型和不追肥、拔节期追氮肥、挑旗期追氮肥3种肥料处理,3次重复。结果表明: 在2种土壤条件下,小麦籽粒产量和各蛋白质组分产量表现为黑土>潮土,除球蛋白产量外,土壤处理间均差异显著。不同时期追施氮肥均显著提高了籽粒产量和蛋白质产量。黑土和潮土配合追施氮肥都可以有效提高小麦籽粒产量,改善品质。     

野生大豆内生真菌对作物促生作用的研究

为了实现绿色生态农业、农作提质增效,加快生防菌剂的研发进度。本研究利用具有广谱拮抗玉米大斑病和大豆疫霉病野生大豆内生真菌Y6R15和Y2S2为试材,通过菌液灌根和叶喷处理,分析不同处理下玉米和大豆苗期干物质和根系指标的变化。结果表明：拮抗菌株Y6R15对玉米叶片和根干重促生作用明显,均提高根长度、根表面积、根体积、根尖数等指标,以根冠比指标标准Y6R15叶喷效果为最佳方式,依据根系指标特征变化Y6R15灌根效果好于叶喷。拮抗菌株Y2S2和Y6R15处理均对大豆有促生作用,效果显著,Y6R15菌株对玉米和大豆均有促生作用。     

Seedling and adult plant resistance to leaf rust in 46 Chinese bread wheat landraces and 39 wheat lines with known Lr genes

Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant cultivars.In the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the greenhouse.These cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping seasons.Furthermore,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat genotypes.Results showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling stage.Nonetheless,Lr1 was detected only in Hongtangliangmai.The field experimental test of the two environments showed that 38 landraces showed slow rusting resistance.Seven cultivars possessed Lr34 but none of the landraces contained Lr37 and Lr46.Lr genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant stage.Lr18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant stage.Lr34 as a slowing rusting gene showed good resistance in the field.Four race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field experiments.Seven race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost resistance.The 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China.     

河套地区种植方式与密度对'张杂谷19号'产量的影响

为明确河套地区不同栽培模式对'张杂谷19号'产量的影响,以新抗旱谷子杂交种'张杂谷19号'为试验材料,研究3种种植方式（干旱无膜、干旱覆膜及灌溉无膜）和5种密度（4.5万、9万、13.5万、22.5万、45万株/hm²）对'张杂谷19号'稳产和丰产性的影响。结果表明,正常灌溉条件下,'张杂谷9号'的产量随着种植密度的增加而增加。当密度为45万株/hm²时产量最高,达到8724.36 kg/hm²。而干旱条件下,适宜种植密度可以同样获得较高产量,与正常灌溉条件下最高产量差异不显著。当种植密度为9万~ 45万株/hm²时,产量普遍提高到7700 kg/hm²以上,最高可达8654.33 kg/hm²。河套地区'张杂谷19号'播前灌溉1次足水、地膜覆盖及种植密度9万~45万株/hm²,可以实现水分高效利用和产量达到较高水平。