Comparing the behavioural thermoregulation response to heat stress by Atlantic salmon parr (Salmo salar) in two rivers

Climate change is expected to increase the frequency and magnitude of extreme thermal events in rivers. The Little Southwest Miramichi River (LSWM) and the Ouelle River (OR) are two Atlantic salmon (Salmo salar) rivers located in eastern Canada, where in recent years, water temperatures have exceeded known thermal limits (~23°C). Once temperature surpasses this threshold, juvenile salmon exploit thermal heterogeneity to behaviourally thermoregulate, forming aggregations in coolwater refuges. This study aimed to determine whether the behavioural thermoregulation response is universal across rivers, arising from common thermal cues. We detailed the temperature and discharge patterns of two geographically distinct rivers from 2010 to 2012 and compared these with aggregation onset temperature. PIT telemetry and snorkelling were used to confirm the presence of aggregations. Mean daily maximum temperature in 2010 was significantly greater in the OR versus the LSWM (p = 0.005), but not in other years (p = 0.090–0.353). Aggregations occurred on 14 and 9 occasions in the OR and LSWM respectively. Temperature at onset of aggregation was significantly greater in the OR (T_onset = 28.3°C) than in the LSWM (T_onset = 27.3°C; p = 0.049). Logistic regression models varied by river and were able to predict the probability of aggregation based on the preceding number of hours >23°C (R² = 0.61 & 0.65; P₅₀ = 27.4°C & 28.9°C; in the OR and LSWM respectively). These results imply the preceding local thermal regime may influence behaviour and indicate a degree of phenotypic plasticity, illustrating a need for localised management strategies.     

盐碱交互胁迫对生姜产量和品质的影响及其数学模型的建立

采用二次饱和D- 最优设计，研究营养液pH 与盐交互胁迫对生姜产量和品质的影响，建立了以pH、盐水平为变量因子，生姜产量和品质为目标函数的二元二次数学模型。模型解析表明，pH 与盐水平对生姜的产量和品质存在显著的交互效应，盐水平为产量的主效应因子，pH 为品质的主效应因子。较低水平的pH 变化对生姜产量无显著影响，当pH 升至7.70时，生姜产量随pH 升高呈快速下降趋势；随盐含量的升高，生姜产量持续降低。随pH 的升高，生姜品质呈缓慢降低的趋势；盐含量在低于77.91 mmol · L^-1 时，生姜品质随盐含量的增加而升高，之后则随盐含量的增加而降低。     

利用酵母双杂交系统筛选与草莓镶脉病毒移动蛋白P1互作的寄主因子

 构建感染草莓镶脉病毒(SVBV)森林草莓的酵母cDNA文库,利用酵母双杂交系统,筛选出与SVBV P1蛋白互作的15种寄主因子。生物信息学分析发现,这15种寄主因子参与茉莉酸途径、泛素化、光合作用、抗病抗逆、蛋白修饰、蛋白运输和氧化还原等多种生物过程。另外,这些寄主因子还具有其他分子功能,包括氧化还原酶活性、蛋白二硫化物异构酶活性和金属离子结合活性等。本研究初步探讨了P1与寄主因子的互作机理,为揭示SVBV侵染森林草莓以及SVBV在寄主中扩展的分子机制提供理论依据。     

耐盐抗旱优质高产棉花新品种‘衡棉1670’的选育研究

抗逆优质丰产棉花新品种的培育及应用是当前棉花生产节水提质增效的关键。‘衡棉1670’是河北省农林科学院旱作农业研究所以中早熟陆地棉品种资源材料‘衡棉210’为母本,以‘衡棉4号’为父本杂交,后代多年南繁北育,经旱棚盐池鉴定选择,在枯黄萎病混生重病地、不防治棉铃虫的高压胁迫下,经过多年连续定向选择育成。其突出表现为抗枯黄萎病、丰产优质、耐盐抗旱节水,适宜在河北省及黄河流域同类生态春播棉区推广种植,2019年8月通过河北省农作物品种审定委员会审定（审定编号为冀审棉20190013）。     

盐胁迫对4种禾本科牧草种子萌发和幼苗生长的影响

通过NaCl溶液(0、1.5、3.0、6.0、9.0g/L)处理4种禾本科牧草种子,测定了种子萌发和幼苗生长有关指标。结果表明:美洲狼尾草较耐盐,在9.0g/L盐溶液处理下比其它品种维持了高的发芽率、发芽指数、活力指数,并且其相对值高,以及较高的相对苗长和根长,盐处理显著提高几种牧草幼苗质膜相对透性,总体上降低胚乳的利用速度和利用效率。     

党的先进性建设如何借鉴国际共产主义运动的基本经验教训

前苏联及东欧共产党丧失执政地位使国际共产主义运动遭受重大挫折的原因有很多，最重要的因素是苏东共产党蜕化变质。没有按照党的先进性来建设党，丧失了党的思想、理论、阶级基础、群众基础、前进方向的先进性，从而失去了它作为无产阶级先锋队的作用，削弱乃至丧失了执政能力，最终葬送了社会主义事业也葬送了党的自身。国际共产主义的经验教训对中国共产党人在全党开展先进性建设的启示是深刻而巨大的：在新的形势下必须坚持党在指导思想上与时俱进；必须从严治党，建立党的先进性建设长效机制；必须加强党的执政能力建设。巩固党的执政基础；必须加大反腐败力度。永葆党的先进性。     

水稻耐盐机理的研究Ⅲ.不同基因型对NaCl吸收和运转的动力学比较

本文应用动力学研究方法比较了具有不同耐盐性的3组共6个水稻基因型对NaCl吸收和运转的差异,结果表明,在外部低NaCl浓度(0.1mmolL~(-1)时,水稻对Na~+的吸收为被动吸收,耐盐基因型对Na~+的吸收速率显著低于盐敏感基因型;对Cl~-的吸收为主动吸收,不同耐盐性基因型吸收Cl~-的动力学参数(V_(?)、K_(?))差异不显著,在外部高NaCl浓度(50mmolL~(-1))时,耐盐基因型对Na~+和cl~-的吸收速率均低于对应的盐敏感基因型。耐盐基因型水稻的Na~+、cl-从根部向地上部的运转率低于对应的盐敏感基因型,这种差异在高盐浓度时更为明显。表明了耐盐基因型水稻地上部对NaCl的排斥作用是吸收控制和运转控制共同作用的结果,使地上部Na~+、Cl-含量相对降低而显出较高的耐盐性。     

Use of space by bank voles (Clethrionomys glareolus) in a polish farm landscape

Movements of bank voles (Clethrionomys glareolus) were studied in a farmland mosaic in Poland. Distances crossed by animals in short-time periods are significantly longer in heterogenous than in homogenous habitats. In long-time and large-spatial scales, a significant portion of the animals in a population travel among habitat elements of the mosaic, reducing the degree of isolation of patch populations and decreasing the probability of local extinction.     

Movement of Xanthomonas campestris pv. vitians in the stems of lettuce and seed contamination

Xanthomonas campestris pv. vitians , the causal agent of bacterial leaf spot of lettuce (BLS), can be seedborne, but the mechanism by which the bacteria contaminates and/or infects lettuce seed is not known. In this study, the capacity of X. campestris pv. vitians to enter and translocate within the vascular system of lettuce plants was examined. The stems of 8- to 11-week-old lettuce plants were stab-inoculated, and movement of X. campestris pv. vitians was monitored at various intervals. At 4, 8, 12 and 16 h post-inoculation (hpi), X. campestris pv. vitians was recovered from 2 to 10 cm above (depending on stem length) and 2 cm below the inoculation site. Xanthomonas campestris pv. vitians was also recovered from surface-disinfested stem sections of spray-inoculated plants. Together, these results are consistent with X. campestris pv. vitians invading and moving systemically within the vascular system of lettuce plants. To investigate the mechanism of seed contamination, lettuce plants at the vegetative stage of growth were spray-inoculated with X. campestris pv. vitians and allowed to develop BLS. Seed collected from these plants had a 2% incidence of X. campestris pv. vitians external colonization, but no bacteria were recovered from within the seed.     

盐胁迫对果树光合生理的影响

结合我们相关的研究结果综述了盐胁迫对果树光合作用的影响。总体来说盐胁迫导致果树净光合速率下降,且这种作用受树种、品种、砧木以及盐的种类、浓度和处理时期的影响;盐胁迫还使叶片干物质积累下降并影响碳水化合物的组成。盐逆境所产生的渗透胁迫和离子毒害而引起的气孔性限制和非气孔性限制则是果树叶片净光合速率下降的原因。此外,盐胁迫使果树叶片的叶绿素荧光效率下降。文章最后还提了出今后研究果树盐胁迫与光合作用的关系应与实际的生产环境相结合。