玉米幼苗吸收硫酸盐(Na235SO4)亲和性的基因效应分析

本文以来源不同的9个玉米自交系及其按双列杂交组合的36个杂交种为材料,研究了玉米幼苗根系对硫酸盐(Na₂³⁵SO₄)亲和性(Km)的基因效应。结果表明,Km的遗传为加性—显性—上位性模型。控制Km的基因作用方式为超显性,显性作用大于加性作用,显性方向指向减效。亲本中正、负效基因的分布不等,显性等位基因的频率高于隐性等位基因的频率。自交系合二和292含显性基因较多,认为这二个自交系是改良根系对营养吸收亲和性的优良亲本材料。     

试1243单交种干物质积累与分配规律、子粒灌浆速率及子粒品质与产量关系的研究

玉米单交种“试1243”是适合黑龙江省第一积温带进行 间作、密植的优质杂交种,是该类型区比较典型的代表品种。为了探索该地区玉米品种的高产生理机制、子粒品质与产量的关系,我们以该品种为试材,以本区广泛种植的 “四单19”和“本玉9”为对照,进行了对比试验。试验在东北农业大学农学院试验站进行。种植条件为：纯N 180 kg/hm²,P₂O₅90kg/hm²,K₂O 180 kg/hm^{2相似文献}   

玉米辽综群体创建、改良及应用研究

以引自美国和选自美国血缘的自交系为基础材料,组建玉米辽综群体。采用S₁表型选择法、S₁家系密植鉴定选择法、配合力选择法对玉米辽综群体进行3轮改良,系统评价8个改良群体的育种潜势。结果表明,S₁家系密植鉴定选择法改良群体效果显著,且方便、实用。以密植鉴定选择法改良的群体辽综C_3-3穗行数增加明显、产量性状GCA水平较高、育种潜力较大。以其为基础群体,运用S1密植选择法结合新种质导入进行后续两轮改良。从不同轮次的改良群体中陆续选育出了6个优良玉米自交系,组配出6个相应的玉米杂交种通过国家或省级审定,新品种累计推广面积122.5万hm²。     

玉米自交系长3的改良与利用

以骨干自交系长₃与5003杂交后与长₃回交,选育出了配合力高、抗病性强、早熟和综合性状好的新自交系K10、HR25和HR3.用其作亲本,育成龙单13、龙单20和黑342等玉米杂交种在生产上大面积推广应用.K10已成为黑龙江省玉米育种的骨干自交系之一。     

套种玉米高产施肥指标的研究与生产实践

通过研究确立了套种玉米施肥与产量的二元二次回归模型，模型经方差分析F值达极显著水平。进一步分析，该研究的三个主放因子对量的影响大小程度是氮＞磷＞钾，其相关程度为0.93。经过模拟寻优，玉米单产9000－9750kg/hm²的N、P、K施量的优化组合是：玉米施氮360kg／hm²，施P₂O₅69.8kg/hm²，施K₂062.7kg/hm²。该施肥指标通过大面积生产示范验证，玉米平均产量在940－9600kg/hm²，比常规栽培田玉米产量7411.5kg/hm²，增产1993.5－2188.5kg/hm²，增产历26.9%－29.5%。增产效果显著。生产示范产量接近目标产量，说明该方程可以为大田预测，研究所得的施肥指标可以作为小麦套种玉米高产施肥的依据。     

玉米子粒色素稳定性比较研究

用比色法对两种玉米子粒花色苷色素的色谱及稳定性进行研究。结果表明：西星赤糯1号玉米子粒色素最大吸收峰为506 nm,酸性条件下为酒红色;黑包公鲜玉米子粒色素的最大吸收峰为528 nm,酸性条件下为玫瑰红色。两种玉米子粒花色苷色素对室内散射光、温度(20℃～60℃)、食盐、蔗糖、葡萄糖、维生素C、柠檬酸、乙酸、防腐剂苯甲酸钠(C₇H₅NaO₂)以及Mg²⁺、Zn²⁺、Mn²⁺、Ca²⁺、K⁺、Na⁺均表现稳定,对室外自然光、氧化剂H₂O₂(30%)、还原剂亚硫酸钠(Na₂SO₃)以及Fe3+、Fe2+、Cu2+表现不稳定。     

转育玉米大斑病抗病单基因Ht的实用性初探

对玉米自交系Mo17转育抗病单基因Ht₂、Ht₃,培育出Mo17的6个近等基因系,通过温室及田间人工接种玉米大斑病菌鉴定及配合力测定.得出在利用多基因抗性的基础上同时转育单基因Ht₁、Ht₂、Ht₃、Ht_N,把单基因尽可能集中到一个自交系或杂交种上;形成“多质系”或“多系品种”,因而具有兼抗多个生理小种的作用,从而延长杂交种的使用寿命.”     

稻田春玉米氮、磷、钾配方施肥数学模型的初步研究

采用氮、磷、钾三因素旋转组合设计,通过计算机模拟寻优,建立了稻田春玉米--杂交晚稻种植制度中玉米产量--施肥量,玉米生产利润--施肥量数学模型:分析了氮(X₁)、磷(X₂)、钾(X₃)的主效应及交互效应与产量的关系,它们对产量的影响为氮＞钾＞磷.筛选出玉米产量≥8250kg/hm²的最优方案为:N394.96～401.25kg/hm²、P₂O₅116.99～121.8kg/hm²、K₂O 232.29～237.06kg/hm²,其比例为N∶P₂O₅K₂O=3.4∶1∶2.并筛选出玉米利润≥6800元/hm²的最优方案为:N380.60～385.55kg/hm²,P₂O₅104.73～108.03kg/hm²、K₂O222.20～225.12kg/hm².其比例为N∶P₂O₅K₂O=3.6∶1∶2.1。     

玉米O2和Wx基因内及O16基因连锁SSR位点的等位变异研究

以13个o2o2基因型的高赖氨酸玉米自交系、3个o16o16基因型的高赖氨酸玉米自交系、13个wxwx基因型的糯玉米自交系和8个普通玉米自交系为材料,用3个o2基因内SSR标记(umc1066、phi057和phil12)、2个与o16基因连锁的SSR标记(umc1141和umc1121)和2个wx基因内SSR标记(phi027和phi061)检测上述材料的基因组DNA,了解3个基因内共7个SSR位点的等位变异情况。结果表明,7个SSR位点均有丰富的等位变异,这些变异可导致o2o2与O2O2基因型、o16o16与O16O16基因型间子粒赖氨酸含量的差异以及wxwx与WxWx基因型间糯性的差异。     

小麦旗叶光呼吸对光强和CO2浓度的响应

为给C₃作物光呼吸等光合参数以及光响应模型和CO₂响应模型的研究提供参考,定量研究了小麦花期旗叶光呼吸速率对光强和CO₂浓度的响应。结果表明,在21%和2%O₂下小麦旗叶光饱和点分别为1 960.629和2 030.120 μmol·m^-2·s^-1。在较弱光强(小于800 μmol·m^-2·s^-1)下,小麦的总光呼吸速率(R_pt)与表观光呼吸(R_pa)均随着光强的升高而增大;当光强大于800 μmol·m^-2·s^-1时,R_pt和R_pa趋于稳定;整体上,不同光强下R_pt与R_pa之间差异较小(P>0.05),这主要是由于在380 μmol·mol^-1 CO₂下,光呼吸的CO₂回收利用率较低。饱和光强下,R_pa随着CO₂浓度的增加呈先上升后下降的趋势,R_pa最大值(Rpmax)所对应的外界CO₂浓度为600 μmol·mol^-1,而R_pt则随着CO₂浓度的升高而降低;在低浓度CO₂(小于380 μmol·mol^-1)条件下,R_pt与R_pa之间差异显著(P<0.05)。R_pt与羧化速率的比值(R_pt /Vc)随着胞间CO₂浓度的升高而呈下降的趋势,而不同光强下R_pt /Vc相对稳定,整体上未达到显著水平(P>0.05)。     

肥料增效剂对夏玉米植物学性状、产量构成及土壤中NH4+-N和NO3--N的动态影响

2014、2015年夏季,试验采用单因素随机区组设计,以先玉335为材料,设置两种肥料增效剂、7种施肥方式,研究大喇叭口期和抽雄期植物学性状、施肥后0、14、28、42 d时0~30 cm和31~60 cm土壤中NH_4~+-N和NO_3~--N含量以及收获时玉米穗部性状和产量差异。结果表明,分期施肥比全部氮肥作底肥更能促进夏玉米茎粗、叶面积、气生根数量、穗长、穗行数和行粒数等增加。与对照和不施用肥料增效剂相比,0~30 cm和31~60 cm土层中施用两种肥料增效剂的NH_4~+-N含量较高,NO_3~--N含量较低,控制了NH_4~+/NO_3~-比例。两种肥料增效剂相比,Entrench效果明显优于NMAX。     

氮素供应和pH值对玉米根系形态的影响

实验设正常供氮(0.5 mmol/L NO3-)和高氮(10 mmol/L NO3-)处理,研究不同pH值水平下(4.5～8.0)氮素供应对玉米根系生长的影响。结果表明,氮供应与溶液pH值对玉米根系的影响不存在互作效应。高氮供应不影响地上部与根的干物质积累;pH值提高有利于促进干物质向地上部分配,向根的分配比例相对下降,根冠比下降。高氮使单株根系总长度平均下降,降幅为34.5%,主要是轴根和侧根长度下降,轴根数和侧根密度受影响较小。在两个氮水平下,总根长、轴根长、侧根长均随pH值的上升表现增加的趋势,高pH值主要增加侧根密度。研究表明,在酸性土壤上,不能通过大量施用硝态氮肥缓解氢离子对根系生长的抑制作用。     

Bioactive Alkaloids from the Sea: A Review

In our ongoing search for bioactive substances from marine organisms, novel alkaloids have been isolated. Pinnatoxins and pinnamine, potent shellfish poisons, were purified from the Okinawan bivalve Pinna muricata. Pinnatoxins activate Ca²⁺ channels. Halichlorine was isolated from the marine sponge Halichondria okadai. This compound inhibits the induction of VCAM-1. Drugs that block VCAM-1 may be useful for treating coronary artery diseases, angina, and noncardiovascular inflammatory diseases. Pinnaic acids, which are cPLA₂ inhibitors, were also obtained from P. muricata. Interestingly, the structures of pinnaic acids are closely related to that of halichlorine. Norzoanthamine hydrochloride, isolated from the colonial zoanthid Zoanthus sp., suppresses decreases in bone weight and strength in ovariectomized mice, and could be a good candidate for an osteoporotic drug. Ircinamine, purified from the marine sponge Ircinia sp., has a reactive thioester. Aburatubolactams, inhibitors of superoxide anion generation, were isolated from Streptomyces sp. This article covers the bioactive marine alkaloids that have been recently isolated by this research group.     

Effect of Solvent System on Extractability of Lipidic Components of Scenedesmus obliquus (M2-1) and Gloeothece sp. on Antioxidant Scavenging Capacity Thereof

Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components—especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH^•) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS^+•)) and biological reactive species (O₂^•− and ^•NO⁻). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH^• and ABTS^+•, respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O₂^•−, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in ^•NO⁻ assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance—which appears to hinge, in particular, on the balance between carotenoids and PUFAs.     

The effect of different factors on the content of nitrate in some potato varieties

Summary The ability for nitrate accumulation in potato tubers as affected by mineral fertilisation (N, K₂O and MgO), genotype and the site of cultivation was studied in a three-year-long field experiment. Fertilisation with potassium chloride and potassium sulphate increased nitrate concentration in the tubers while additional magnesium fertilisation reduced nitrate concentration. Significant differences in nitrate concentrations were observed in potato tubers depending on genetic conditions as well as on the cultivation location (with the same soil and climatic conditions, varieties and tillage). The nitrate content decreased as the result of storage at 4 °C. Concentration of these ions in tubers of table and industrial potatoes did not exceed Acceptable Daily Intake level determined by WHO.     

硫化氢对镉胁迫下小麦幼苗的生长及生理指标的影响

为了解硫化氢(H_2S)对Cd~(2+)胁迫下小麦幼苗生长的缓解机理,以小麦品种苏科麦一号为材料,在水培条件下,测定外源H_2S(供体为NaHS溶液)预处理对Cd~(2+)胁迫下(CdCl_2浓度为50μmol·L~(-1))小麦幼苗生长和生理指标的影响。结果显示,外源H_2S预处理显著提高Cd~(2+)胁迫下小麦幼苗的株高、地上部生物量、非蛋白巯基化合物含量、叶片光合色素含量、净光合速率、叶绿素荧光相关指标(PSⅡ的光合性能指数、单位激发态面积吸收的能量、用于还原Q_A和用于电子传递的能量、非光化学淬灭)和根部Cd含量;显著降低小麦叶片中的过氧化物质(丙二醛、过氧化氢和超氧根阴离子)含量及地上部分Cd含量和Cd转运系数。综上所述,外源H_2S预处理可清除Cd~(2+)胁迫小麦幼苗叶片中的活性氧自由基,减少其对光合色素分子的破坏,降低膜脂过氧化程度,保护光合电子传递系统,增加热耗散,提高光合能力,缓解Cd~(2+)对小麦幼苗生长的抑制,以50μmol·L~(-1)的NaHS效果最好。     

Effect of different Cs concentrations on overall plant growth and Cs distribution in soybean

The absorption and dynamics of Cs in crops can be measured and examined using not only ¹³⁷Cs but also ¹³³Cs, a stable isotope which can be analyzed in a regular laboratory. When ¹³³Cs is used, however, the concentration of added ¹³³Cs must be set higher than that in the soil solution due to the detection sensitivity of inductively coupled plasma optical emission spectrometry (ICP-OES). There is concern that such high Cs concentrations may adversely affect crops and interfere with Cs dynamics. Using soybean as a test product, we first examined the initial growth of soybean cultivated under exposure to solutions with different ¹³³Cs concentrations. In combination with each ¹³³Cs concentration, two potassium (K) concentrations were tested. Results show that at both K concentrations, growth was inhibited under ¹³³Cs concentrations higher than 1 × 10^?3 mol L^?1. Soybeans cultivated at ¹³³Cs concentrations higher than 1 × 10^?6 mol L^?1 can be subject to ICP-OES for measuring ¹³³Cs concentrations in the plant tissue. Next, soybeans cultivated under different ¹³³Cs concentrations throughout growth were examined for Cs distribution in the plants. The distribution patterns of Cs in soybean plants cultivated at ¹³³Cs concentrations equivalent to those found in the soil were almost identical to those in plants cultivated at measurable ¹³³Cs concentrations (1 × 10^?6–1 × 10^?4 mol L^?1) as measured with ICP-OES. Therefore, in our investigation, ¹³³Cs distribution in soybean plants treated with up to 1 × 10^?4 mol L^?1 was considered equivalent to that in plants cultivated in the field.     

Difference In Tolerance To Potassium Deficiency Between Two Maize Inbred Lines

Abstract

Northeast China Produces An Abundance of Maize (Zea Mays L.), and Improvement of Maize Yield At This Region Correlates Closely With Ensure Food Supply Safely of China. in Recent Years, Deficiency Or Relative Deficiency of Potassium (K) in The Soil Is An Important Limitation To Maize Production. Maize inbred Lines Tolerant To K Deficiency (T) and Sensitive To K Deficiency (C) Were Hydroponically Grown in 1/2 Hoagland Solution To Study The Possible Mechanism of Maize Tolerance To Potassium Deficiency From Physiological Point of View. With The Reduction of K⁺ Concentration, Dw of The Plant Became Apparently Greater in T Than in C, The Symptom of Potassium Deficiency Advanced in C. Under K Deficiency, The Taproot Elongation increased and Root Top Ratio Decreased To A Greater Degree in C Than in T, C Had Fawer Lateral Roots. T Had A Stronger K⁺-Uptake Ability Than C, and The Difference Was More Obvious in Culture Solution With A Lower K⁺ Concentrations of Culture Solution. K⁺ Dependent H⁺ Extrusion From The Root Treated With K⁺ Deficiency Was Larger in T Than in C.     

Impact of ocean acidification on energy metabolism of oyster, Crassostrea gigas--changes in metabolic pathways and thermal response

Climate change with increasing temperature and ocean acidification (OA) poses risks for marine ecosystems. According to Pörtner and Farrell [1], synergistic effects of elevated temperature and CO₂-induced OA on energy metabolism will narrow the thermal tolerance window of marine ectothermal animals. To test this hypothesis, we investigated the effect of an acute temperature rise on energy metabolism of the oyster, Crassostrea gigas chronically exposed to elevated CO₂ levels (partial pressure of CO₂ in the seawater ~0.15 kPa, seawater pH ~ 7.7). Within one month of incubation at elevated Pco₂ and 15 °C hemolymph pH fell (pH_e = 7.1 ± 0.2 (CO₂-group) vs. 7.6 ± 0.1 (control)) and P_eco₂ values in hemolymph increased (0.5 ± 0.2 kPa (CO₂-group) vs. 0.2 ± 0.04 kPa (control)). Slightly but significantly elevated bicarbonate concentrations in the hemolymph of CO₂-incubated oysters ([HCO⁻ ₃]_e = 1.8 ± 0.3 mM (CO₂-group) vs. 1.3 ± 0.1 mM (control)) indicate only minimal regulation of extracellular acid-base status. At the acclimation temperature of 15 °C the OA-induced decrease in pH_e did not lead to metabolic depression in oysters as standard metabolism rates (SMR) of CO₂-exposed oysters were similar to controls. Upon acute warming SMR rose in both groups, but displayed a stronger increase in the CO₂-incubated group. Investigation in isolated gill cells revealed a similar temperaturedependence of respiration between groups. Furthermore, the fraction of cellular energy demand for ion regulation via Na⁺/K⁺-ATPase was not affected by chronic hypercapnia or temperature. Metabolic profiling using ¹H-NMR spectroscopy revealed substantial changes in some tissues following OA exposure at 15 °C. In mantle tissue alanine and ATP levels decreased significantly whereas an increase in succinate levels was observed in gill tissue. These findings suggest shifts in metabolic pathways following OA-exposure. Our study confirms that OA affects energy metabolism in oysters and suggests that climate change may affect populations of sessile coastal invertebrates such as mollusks.     

Na+/K+-ATPase Activation by cAMP in the Midgut of Lutzomyia longipalpis (Lutz & Neiva, 1912; Diptera: Psychodidae)

Lutzomyia longipalpis (Lutz & Neiva, 1912) females have been intensively studied regarding the regulation of midgut pH. The mechanisms involved in pH regulation are complex, and some aspects remain to be clarified. Here, we investigated the role of the Na⁺/K⁺-ATPase pump as an electrochemical potential generator and its modulation by the second messenger cAMP in the midgut of female L. longipalpis. Our results suggest that not only may Na⁺/K⁺-ATPase be the main generator of an electrochemical potential across membranes in the midgut of female L. longipalpis, but also its activity is positively regulated by cAMP. cAMP-mediated Na⁺/K⁺-ATPase pump activity might be necessary to maintain the transport of the nutrients produced during blood digestion.