普通小麦1BL—1RS K,V型雄性不育体系育性恢复的研究

对１ＢＬ－１ＲＳ Ｋ,Ｖ型雄性不育系及其保持素与中国春及其第一部分同源群染色体全部６个缺－四体杂种Ｆ１的育性恢复进行了研究。结果表明：Ｋ型杂种的育笥恢复主要受１ＢＳ上Ｒｆｖ１基因的控制;而Ｖ杂种则受Ｒｆｖ１的１Ｄ染色上育性恢复基因的共同控制;在保持１Ｄ正常剂量的情况下,使恢复系中载有Ｒｆｖ１的１Ｂ染色体（片段）加倍,如１Ａ缺体－１Ｂ四体能使Ｋ,Ｖ型杂种1Ｆ的育性完全恢复。     

铝处理下小麦幼苗根系膜脂过氧化作用 和质膜微囊ATP酶活性的变化

采用水培的方法研究了Al对小麦（Triticum aestivum L.cv Yangmai No.5）幼苗的生长、根尖组织膜脂过氧化作用、保护酶的活性和质膜结合酶H     

VE161小麦促进部分同源染色体配对的遗传

ＶＥ１６１小麦包括具有一对长穗偃麦草染色体的雄性不育代换系、可育附加系和杂育系,杂育系由其代换系×附加系产生。ＶＥ１６１小麦在与其它小麦品系的杂交Ｆ１中,具有促进部分同源染色体配对的作用,但其本身部分同源配对频率较低。研究结果表明,ＶＥ１６１小麦本身部分同源染色体配对水平较低,是因其小麦染色体组中存在有一对纯合隐性上位基因,它能够抑制Ｅ染色体（Ｅｐｈ基因）,促进部分同源染色体配对作用的表达,而一般小麦品系中具有该基因的相对显性基因。同时,在促进小麦部分同源染色体配对作用上,Ｅ染色体（Ｅｐｈ基因）具有剂量效应     

干旱条件下冬小麦不同叶龄叶绿素荧光及叶黄素循环组分的变化(英文)

干旱条件下冬小麦叶片光化学效率（Ｆｖ／Ｆｍ）的降低伴随着叶黄素循环组分玉米黄质含量的增加。干旱初期,Ｆｖ／Ｆｍ 的降低约在暗置过夜后完全恢复。当干旱诱导的玉米黄质含量的增加达最大值时,Ｆｖ／Ｆｍ 不可逆下降,Ｆｏ 上升,表明发生了光破坏。与老叶相比,干旱条件下功能叶具有较高的玉米黄质含量,对光破坏的抗性较强。推测干旱条件下老叶不可逆衰老与其依赖于叶黄素循环的耗散过剩光能能力的下降有关。     

Cytological Evidences of a Possible Mode of Nurture Absorption of the Differentiating Embryo in Triticum aestivum

Coleorhiza covered the radicle of differentiating wheat embryo and morphologically appeared as tapered tissue with an attached globular protrusion. In the early phase of differentiation a series of structural changes occurred at some local areas of the coleorhiza. By light and electron microscopic inspections combined with fluorescence labelling it was uncovered that cells of the peripheral layers of the globular protrusion and the neck region underneath gradually exhibited degeneration and disintegration while a lot of broken plasmodesmata still remained at the boundary wall of the inner surviving cells. Impermeable fluorescence probe 4.3 kD FITC- dextran could enter these living cells and continuously diffuse to their neighborhood. All these showed that a direct communication was estabhshed between the symplasm of coleorhiza and the external medium and the remaining plasmodesmata, though broken in one end, might function as symplasmic pathway for external material incorporation. Analyzing the above described results a possible mode of nurture absorption of differentiating embryo then could bo recognized; particularly, comparing with the globular pretmsion the limited area of the neck region towards dorsal side might play a more important role in nurture absorption of the young embryo. Temporal and partial disintegration of the neck region and consequential regeneration in situ and increase of plasmodesmatal conductivity in the surrounding surviving cell group were most favourable to the incorporation and intercellular translocation of the external material for the coleorhiza. A large quantity of nutrients intruding into the coleorhiza at proper instant through the transiently opened route would effectively coordinate with the need of embryo differentiation without leaving apparent destruction to the coleorhiza.     

Carbon Balance of a Winter Wheat-Root Microbiota System Under Elevated CO2

We examined the carbon budget of young winter wheat plants and their associated microorganisms as affected by a doubling of the atmospheric CO₂ concentration (700 μmol mol^-1). Plants were grown hydroponically in pre-sterilised sand at a controlled irradiance and temperature regime. Net photosynthesis (P_N) and respiration (R_D) rates of roots and shoots were measured continuously, plant growth and carbon distribution in the plant-root medium-associated microorganism system were determined destructively in interval-based analyses. P_N in elevated CO₂ grown plants (EC) was 123% of that in the control (AC) plants when averaged over the whole life span (39-d-old plants, 34 d in EC), but the percentage varied with the developmental stage being 115, 88, and 167% in the pretillering, tillering, and posttillering phase, respectively. There was a transient depression of P_N, higher amplitude of day/night fluctuations of the chloroplast starch content, and depression of carbon content in rhizosphere of EC plants during the period of tillering. After 34 d in EC, carbon content in shoots, roots, and in rhizodepositions was enhanced by the factors 1.05, 1.28, and 1.96, respectively. Carbon partitioning between above and belowground biomass was not affected by EC, however, proportionally more C in the belowground partitioning was allocated into the root biomass. Carbon flow from roots to rhizodepositions and rhizosphere microflora was proportional to P_N; its fraction in daily assimilated carbon decreased from young (17%) to order (3-4%) plants. This revised version was published online in June 2006 with corrections to the Cover Date.     

小麦胚胎分化时营养吸收一种可能方式的细胞学论据

以光学与电子显微镜术结合荧光标记物示踪,对小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）胚胎分化时胚根鞘的形态结构特征的变化与营养吸收相联系进行了实验观察。发现在分化前期胚根鞘顶端的球状突起处和颈区朝向颖果背面一侧的特定位点上出现了结构的变更;外沿局部细胞的衰退瓦解导致这些区段内侧存活细胞分界壁上出现大量残存的胞间连丝。不透膜的荧光物质、分子量达４３ｋＤ的ＦＩＴＣｄｅｘｔｒａｎ可进入球状突起和颈区多处细胞,表明残存胞间连丝仍具有共质传输功能,是分化幼胚摄取外围介质中营养物质的一种方式。分化进程中颈区的短时期局部缺损与随后的修复以及衰退区周围多层细胞胞间通透性的显著增大,既有利于外源物质的适时与大量掺入和在细胞间的快速运转,并仍保持了胚根鞘的结构完整,与分化前期胚胎对养分的大量需求正相适应,显示出胚根鞘的颈区比之球状突起处在营养吸收上占有更重要的地位。     

Source-sink manipulation effects on postanthesis photosynthesis and grain setting on spike in winter wheat

Source-sink manipulation could regulate the net photosynthetic rate (PN) of winter wheat after anthesis, however, the direction and magnitude of the regulation varied with time after anthesis. The PN was significantly increased by source reduction at the initial time of grain filling, but sink reduction had little influence on the PN, which suggested that the sink (spike) limitation did not occur at this time. Source-sink relation markedly affected PN during rapid grain filling. The PN was increased by source reduction and decreased by sink reduction significantly, which indicated that PN was closely associated with the change of source or sink size. The effect of source-sink manipulation on PN had some relationship with the occurrence of plant senescence at the time of late grain filling. Source reduction accelerated the senescence and dropped the PN, meanwhile, sink reduction delayed the senescence and promoted the PN. A direct relation between the effect of source-sink manipulation on PN and stomatal limitation was not found. Removing one quarter of leaves (RQ) had little influence on spike development after anthesis. In this case there was enough compensation in source production through photosynthesis. Removing one half of leaves (RH) made grain mass per spike and mass of grains lowered, especially the grain mass in the top and base positions of spike declined markedly. The source supply was grain-limiting. Removing one quarter of spikelets (RS) was beneficial to grain-setting in the remaining spikelets, leading to the increase of grain mass. Thus promoting the source supply of photosynthates after anthesis is of major importance for grain to set and to develop.     

Effects of DIMBOA levels in wheat on the susceptibility of the grain aphid (Sitobion avenue) to deltamethrin

The effects of DIMBOA in cultivars of wheat on aphid antibiosis and tolerance to the insecticide deltamethrin were investigated for the aphid Sitobion auenae. Over 48 hours the mean relative growth rate differed significantly between nymphs of S. auenae reared on wheat cultivars containing different levels of DIMBOA. Nymphs on the resistant cv. Altar showed a significantly greater susceptibility to deltamethrin, with nearly a three-fold increase in the relative toxicity of deltamethrin, compared with the susceptible cv. Dollarbird. The LC₅₀, adjusted for weight, was reduced by 91% for nymphs reared on the high DIMBOA cultivar. The potential for the enhancement of predation under a reduced pesticide régime is discussed in relation to this research.     

长期定位施肥土壤中AM真菌对寄主植物的侵染状况

分别于2003年9月和2004年5月在莱阳农学院长期(26年)定位施肥试验田采集玉米和小麦根系,以测定不同施肥处理对丛枝菌根(AM)真菌侵染状况的影响。结果表明长期定位施氮(N)肥显著降低了AM真菌对寄主植物的侵染率(MCP)、丛枝着生率(ACP)、单位根长泡囊数(NV)和侵入点数(NE)。高N处理的小麦MCP低于低N处理,高N处理的玉米ACP低于低N处理。长期定位施有机肥,尤其是高有机肥处理显著降低了MCP、ACP和NE。有机肥和N肥配施也降低了MCP、ACP、NV和NE,以高有机肥和高N肥配施处理的降低效应最大。除小麦根系NV外,长期定位NPK配合施用降低了玉米和小麦的MCP、ACP、NV和NE。其中,以NP处理的玉米ACP、小麦的MCP和ACP最低。另外,低有机肥与N肥配施和NPK配施处理条件下玉米MCP高于小麦。结论认为不同施肥体制对作物菌根生长发育及其结构具有不同影响,而且有机肥和N肥在影响AM真菌侵染方面存在互作。