盐胁迫对菘蓝幼苗生长和抗性生理的影响

以“定蓝1号”为试验材料,采用不同浓度NaCl溶液(0,30,60,90,120和150 mmol·L^-1)对菘蓝幼苗进行处理,胁迫14 d后测定了其生长指标、生物量积累、叶片相对含水量、根系活力、根质膜透性、渗透调节物质含量以及抗氧化酶活性等指标,分析不同程度盐胁迫对菘蓝幼苗生长和抗性生理的影响。结果表明:NaCl胁迫对菘蓝幼苗株高和根长都有抑制作用,对根和叶的物质积累也有显著影响,并随浓度的递增呈降低的趋势;菘蓝幼苗叶片相对含水量和根系活力均随NaCl浓度的增加呈现下降趋势,而根质膜透性、叶片脯氨酸含量则呈升高趋势;丙二醛(MDA)含量、组织自动氧化速率(RAD)、过氧化物酶(POD)活性和超氧化物歧化酶(SOD)活性都随NaCl浓度的增加呈先升高后降低的趋势。但当NaCl浓度低于90 mmol·L^-1时,菘蓝幼苗的生长没有受到盐胁迫的明显抑制,根系活力降低不明显,脯氨酸、丙二醛含量和保护酶活性也未显著升高,说明菘蓝幼苗对低浓度盐环境具有一定的耐受性。     

Male-to-female aggression in cage-housed common pheasants (Phasianus colchicus) during the breeding season was not related to male plasma testosterone level

1. The aim of this study was to investigate if male-to-female aggression of common pheasants in the course of the breeding season was related to the concentration of plasma testosterone and/or other biochemical plasma indicators in male pheasants housed in breeding cages. The influence of season on the concentration of testosterone and biochemical indicators was also investigated.

2. Males were divided into non-aggressive and aggressive groups during the breeding season based on ethological evaluation. At the beginning, in the middle and at the end of the breeding season, a blood sample was taken from all males on the same day and the concentration of selected biochemical indicators and the total circulating testosterone in the plasma were determined.

3. Male-to-female aggression during the breeding season of pheasants was not influenced by the total plasma testosterone of males.

4. The concentration of total plasma testosterone in males decreased gradually during the breeding season.

5. Male-to-female aggression of pheasants did not have a significant effect on any of the assessed biochemical indicators.

6. The influence of the breeding season affected the activities of alanine aminotransferase and aspartate aminotransferase as well as the concentrations of glucose, magnesium, potassium and chloride in the blood plasma of cage-housed male pheasants.     

基质对黑果腺肋花楸幼苗生长的影响

以黑果腺肋花楸(Aronia melanocarpa)为试验材料,选用田园土、泥炭土、珍珠岩和黄沙,采用正交试验设计,研究不同基质配比对黑果腺肋花楸成苗率以及幼苗形态指标和生理指标的影响。结果表明,不同育苗基质对黑果腺肋花楸出苗率、苗高、地径、主根长、侧根数和高径比等形态指标以及根系活力、可溶性糖、淀粉和蛋白质等生理指标的影响差异显著,综合分析各项指标,筛选出适合黑果腺肋花楸容器育苗的栽培基质为田园土(40%)+泥炭土(30%)+黄沙(30%)、田园土(40%)+珍珠岩(30%)+黄沙(30%)、田园土(40%)+泥炭土(30%)+珍珠岩(30%)和田园土(60%)+泥炭土(20%)+黄沙(20%)。     

穗期玉米昼夜生理状态规律的遥感综合探测研究

针对QY、PRI、NDVI、水势分别从不同的方面反映玉米的生理状况,以甜糯二号玉米作为材料,通过田间试验测量玉米昼夜4个参数值,研究了QY、PRI、NDVI、水势4个参数的昼夜变化,并且分析它们之间的相关性。结果表明,QY、水势、PRI三者具有很强的相关性,并且能建立回归模型表示它们之间的联系。     

低海拔异地育肥牦牛与本地杂交肉牛(秦川×西门塔尔)在不同非蛋白氮水平饲粮条件下血液生理生化指标及生长性能的差异

为探究异地育肥牦牛模式,本试验对比了低海拔异地育肥耗牛与本地杂交肉牛(秦川×西门塔尔)在同等条件下血液生理生化指标和生长性能的差异。将体重相近的8头1岁本地杂交肉牛(秦川×西门塔尔)和8头4岁青海牦牛各分为2组,每组4头,同一品种的2组试验牛分别饲喂低非蛋白氮饲粮[LNPN,饲粮中缓释尿素添加量为1.0%(干物质基础)]和高非蛋白氮饲粮[HNPN,饲粮中缓释尿素添加量为1.5%(干物质基础)]。预试期10 d,正试期50 d。结果发现:牦牛与肉牛均在LNPN条件下表现出最高的平均日采食量和最小的料重比。饲粮非蛋白氮水平未对牦牛与肉牛的血常规指标造成显著影响(P0.05),但是牦牛在各饲粮条件下中性粒细胞数目(Gran#)、平均红细胞体积(MCV)、平均红细胞血红蛋白含量(MCH)、红细胞分布宽度标准差(RDW-SD)、平均血小板体积(MPV)和血小板分布宽度(PDW)显著高于肉牛(P0.05),而平均红细胞血红蛋白浓度(M CHC)和血小板数目(PLT)显著低于肉牛(P0.05)。饲粮非蛋白氮水平未对肉牛和牦牛各项血清生化指标产生显著影响(P0.05)。牦牛在各饲粮条件下血清总蛋白(TP)、尿素氮(UN)、肌酐(GREA)、免疫球蛋白A(Ig A)、免疫球蛋白M(Ig M)和免疫球蛋白G(Ig G)水平均显著高于肉牛(P0.05)。牦牛在HNPN条件下的血清白蛋白(ALB)水平显著低于LNPN条件下(P0.05)。本试验结果表明,在肉牛和牦牛育肥饲粮中添加1.0%的缓释尿素替代饲粮蛋白质是可行的;低海拔异地育肥牦牛不会对牦牛健康产生不利影响。     

Improving cereal yield forecasts in Europe – The impact of weather extremes

The impact of extreme events (such as prolonged droughts, heat waves, cold shocks and frost) is poorly represented by most of the existing yield forecasting systems. Two new model-based approaches that account for the impact of extreme weather events on crop production are presented as a way to improve yield forecasts, both based on the Crop Growth Monitoring System (CGMS) of the European Commission. A first approach includes simple relations – consistent with the degree of complexity of the most generic crop simulators – to explicitly model the impact of these events on leaf development and yield formation. A second approach is a hybrid system which adds selected agro-climatic indicators (accounting for drought and cold/heat stress) to the previous one. The new proposed methods, together with the CGMS-standard approach and a system exclusively based on selected agro-climatic indicators, were evaluated in a comparative fashion for their forecasting reliability. The four systems were assessed for the main micro- and macro-thermal cereal crops grown in highly productive European countries. The workflow included the statistical post-processing of model outputs aggregated at national level with historical series (1995–2013) of official yields, followed by a cross-validation for forecasting events triggered at flowering, maturity and at an intermediate stage. With the system based on agro-climatic indicators, satisfactory performances were limited to microthermal crops grown in Mediterranean environments (i.e. crop production systems mainly driven by rainfall distribution). Compared to CGMS-standard system, the newly proposed approaches increased the forecasting reliability in 94% of the combinations crop × country × forecasting moment. In particular, the explicit simulation of the impact of extreme events explained a large part of the inter-annual variability (up to +44% for spring barley in Poland), while the addition of agro-climatic indicators to the workflow mostly added accuracy to an already satisfactory forecasting system.     

基于氮梯度加载下的温室核桃砧木苗生长生理特性变化

【目的】探究新疆核桃砧木苗生长特征及生理特性对氮梯度的响应,为核桃砧木苗施氮标准化的探究奠定基础。【方法】以阿克苏厚皮农家种质核桃砧木苗为研究对象,进行不同梯度的氮素诱导,测定核桃砧木苗生长及生理指标。【结果】基于氮梯度加载下的核桃砧木苗株高、地径、叶片数、叶长、光合色素含量、可溶性蛋白质含量、可溶性糖含量、硝酸还原酶活性、谷氨酰胺合成酶活性均呈上升趋势,并在15 g.a^-1.m^-2处理下达到最高值。【结论】适量地增施氮肥有利于核桃砧木苗的生长、提高砧木苗体内营养物质含量以及促进氮代谢能力。     

Soil physical changes and maize growth in a structurally fragile tropical soil due to mulching and duration between irrigation intervals

Under tropical meteorological conditions, the volume of soil explored by plant roots is crucial for crop growth as it allows increased water and nutrient use efficiency. We hypothesized that, under different irrigation intervals, leguminous mulch can extend the duration between irrigation events but maintain crop performance, because decreased evaporative fluxes also reduce constraints to root exploration imposed by mechanical stress. We evaluated the combined effects of leguminous mulch and irrigation intervals on soil physical properties to determine whether the growth and productivity of maize were modified in a structurally fragile tropical soil. The experiment involved the following treatments: 4‐day irrigation intervals with soil mulched (4C) or bare (4S), 6‐day irrigation intervals with soil mulched (6C) or bare (6S), 8‐day irrigation intervals with soil mulched (8C) or bare (8S) and 10‐day irrigation intervals with soil mulched (10C) or bare (10S). Mulch decreased soil penetration resistance and increased to 4 days the favourable time for root development in drying soil. Relative to bare soil, mulch with a 6‐day irrigation interval almost doubled nitrogen uptake post‐tasselling, which decreased nitrogen remobilization and increased the crop growth rate during this stage. These conditions had a positive effect on the transpiration rate and stomatal conductance as well as on the growth and yield of maize. A 6‐day irrigation interval with mulch compared to 4 days with bare soil resulted in similar conditions for root development, but greater uptake of nitrogen (102.73–78.70 kg/ha) and better yield (6.2–5.3 t/ha), which means greater efficiency in nitrogen and water use.     

甘蓝型油菜耐低温生长生理生化响应机制

为提高甘蓝型油菜耐寒育种过程中的筛选效率，研究甘蓝型油菜耐低温机理，以8个不同抗寒性的甘蓝型油菜为材料，对低温条件下各材料的生物量、叶绿素、脯氨酸和相对电导率进行测定，发现在室外平均气温2.75℃时，抗性材料的生物量、叶绿素和脯氨酸的累积量都显著高于敏感材料，相对电导率没有显著差异；当平均气温7.52℃回升至12.39℃，抗性材料和敏感材料生物量的累积量无显著差异；在恒定低温10℃/4℃处理下抗性材料和敏感材料在处理前3周生物量均持续累积，但从第4周开始敏感材料新叶出现白斑，生物量减少，抗性材料老叶出现白斑，生物量维持不变。结果表明，耐低温材料在低温条件下叶绿素含量受到的影响较小，脯氨酸的积累量持续上升，具有较强的快速适应能力，在低温下具有显著的持续生长优势。     

裂褶菌多糖的研究进展

裂褶菌多糖(Schizophyllan)是裂褶菌(Schizophyllum commune)的主要活性成分之一.综述了裂褶菌多糖结构、提取纯化工艺和生理活性功能等方面的研究进展.