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61.
Cytologic and embryologic studies on the reproductive pattern of male sterility line C1001 in rice (Oryza saliva L.) indicated that several types of apomixis were discovered in partial strains of male sterility line C1001 in rice. Under a fully separate condition, two possible apomixis embryogenesis ways in the ovules were observed: One way was that the embryo was initiated from the somatic cells of the ovules, and then pushed against the embryo sac to develop into a mature embryo. The other way was that the embryo was from the unfertilized egg cell or one of synergids, and then developed into a mature embryo in the form of haploid parthenogenesis without forming endosperm. Besides, the antipodal cells migrated in the embryo sac, and their cytoplasm became thin and vacuolated while mitosis was taking place, giving rise to a multicellular structure or a group of large cells each containing several nuclei. This paper also discusses the significance and patterns of apomixis in rice C1001. 相似文献
62.
水稻品种鉴别目前常采用种子形态分析、蛋白和同工酶的聚丙烯酸胺凝胶电泳分析等方法,其缺点是试剂有毒,分析时间长,且很难区别亲缘关系接近的同母异父杂交水稻种子.毛细管电泳是一种高效分离技术【‘’‘〕,具有快速、微量、自动化等优点.本文采用毛细管区带电泳(CZE)对国产13种水稻种子胚乳贮藏蛋白进行初步研究,探讨了作为品种鉴别模式的实际可操作性,以期能为品种鉴别提供新的有效手段.仪器:BiofocusTM3000型(Bio-RadUSA)毛细管电泳仪,配紫外可见检测器和恒温装置.13种水稻种子中包括两组同母异父杂交种子(每组… 相似文献
63.
反应条件对稻杆热解产物分布的影响 总被引:10,自引:0,他引:10
以稻杆为研究对象,在温度650℃-1000℃,考察了热解因素包括最终温度,析出挥发性产物停留时间,传热与传质强化措施,原料颗粒尺寸和原料种类对稻杆在间壁式加热固定床上热解产物分布的影响。结果表明,温度,停留时间,传热与传质强化措施对热解产物分布影响显著,转化率随各种反应条件的变化可高达80%。 相似文献
64.
三十烷醇在GA_3影响水稻幼苗生长和生理性状中的增效作用 总被引:2,自引:0,他引:2
微量三十烷醇(TRIA)与GA3配合使用,比GA3单独使用能明显地促进幼苗生长和增加幼苗干物质积累.同时还增强了GA3对幼叶中叶绿素含量、可溶性蛋白质含量、呼吸速率、细胞膜透性和过氧化物酶活性的影响.GA3+TRIA与GA3处理相比,促进幼叶内源GA3水平提高,稳定保持内源ZT于一定水平,TRIA在GA3低浓度时降低IAA水平,在高浓度时则提高IAA水平.作者认为TRIA可作为GA3处理时的增效剂. 相似文献
65.
Kobayashi T Nakanishi H Nishizawa NK 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(9):900-913
Higher plants utilize various mechanisms to maintain iron homeostasis. To acquire sparingly soluble iron from the rhizosphere, graminaceous plants synthesize natural iron (III) chelators known as mugineic acid family phytosiderophores (MAs). Recent research has uncovered various genes involved in iron uptake and translocation, as well as factors regulating the expression of these genes, especially in rice. Manipulation of these molecular components is used to produce transgenic crops with enhanced tolerance to iron deficiency, or with a high seed iron content. Since iron homeostasis is closely linked to that of other mineral elements, an understanding of this phenomenon will serve as the basis for the production of crops with low concentrations of toxic metals and transgenic plants for phytoremediation. 相似文献
66.
超高效液相色谱-串联质谱法测定水稻基质中阿维菌素残留量 总被引:11,自引:0,他引:11
建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)测定水稻基质中阿维菌素残留量,考察了基质效应,并对实际样品进行了检测.稻田土、稻壳、糙米和稻杆经乙腈振荡提取,稻田水经乙酸乙酯液液分配提取后,用C18固相萃取小柱或弗罗里硅土柱净化,采用UPLC-MS/MS正离子扫描测定残留的阿维菌素.稻田土、稻田水和糙米的3种添加浓度(1.0,10.0和100 μg/kg或μg/L)的平均回收率为84%~107%,相对标准偏差为4.7%~13.6%.稻壳和稻杆的2档添加浓度(10.0和100 μg/kg)的平均回收率为90%和103%,相对标准偏差为8.4%~12.9%.本方法在稻田水、糙米和稻田土中的检出限为0.3μg/kg在稻壳和稻杆中检出限为3.0 μg/kg,低于欧盟和日本在稻米中制定的阿维菌素最大残留限量值.阿维菌素在2.0~100 μg/L范围内线性关系良好( r> 0.999). 相似文献
67.
Rice husk silica catalyst loaded with 10 wt% vanadium was synthesized from agricultural biomass via a sol-gel synthetic route at pH = 9. The catalyst was characterized by different physico-chemical methods. The FTIR spectra showed the formation of Si–O–V and V=O stretching bands. The presence of vanadium was confirmed by EDX elemental analysis. RH-10V possessed a high specific surface area of 276 m2/g and pore volume of 0.83 ml/g. The prepared catalyst possessed a narrow pore size distribution centered around 7.9 nm. The catalytic performance of RH-10V was tested in the oxidation of acetophenone at 70 ℃. RH-10V was found to be an active catalyst in the oxidation of acetophenone, producing 36.28% conversion efficiency. The products identified were benzoic acid, 2-hydroxyacetophenone, phenol, acetic acid, and 3-hydroxyacetophenone. 相似文献
68.
Chongxin Yin Min Wang Qingzhi Ma Huiyang Bian Hao Ren Hongqi Dai Jinlan Cheng 《Molecules (Basel, Switzerland)》2021,26(14)
Rice straw hydrotropic lignin was extracted from p-Toluene sulfonic acid (p-TsOH) fractionation with a different combined delignification factor (CDF). Hydrotropic lignin characterization was systematically investigated, and alkaline lignin was also studied for the contrast. Results showed that the hydrotropic rice straw lignin particle was in nanometer scopes. Compared with alkaline lignin, the hydrotropic lignin had greater molecular weight. NMR analysis showed that β-aryl ether linkage was well preserved at low severities, and the unsaturation in the side chain of hydrotropic lignin was high. H units and G units were preferentially degraded and subsequently condensed at high severity. High severity also resulted in the cleavage of part β-aryl ether linkage. 31P-NMR showed the decrease in aliphatic hydroxyl groups and the increasing carboxyl group content at high severity. The maximum weight loss temperature of the hydrotropic lignin was in the range of 330–350 °C, higher than the alkaline lignin, and the glass conversion temperature (Tg) of the hydrotropic lignin was in the range of 107–125 °C, lower than that of the alkaline lignin. The hydrotropic lignin has high β-aryl ether linkage content, high activity, nanoscale particle size, and low Tg, which is beneficial for its further valorization. 相似文献
69.
以75 MPa静水高压处理萌动的水稻种子12 h,成苗后移栽至大田,研究高压处理后植株剑叶光合特性的变化。结果显示,静水高压处理后,粤香占和粤丰占种子的发芽率分别降低了14.4% 和16.6%,成苗率分别降至对照的24.6%和21.9%,生长明显受抑制,幼苗的株高在35天左右才能追赶上对照。高压处理的粤香占剑叶在生育过程中的净光合速率(Pn)和表观量子效率(AQY)的总平均值分别比未处理的对照增加了9.2%和12.4%,而粤丰占则分别增加5.7%和17.4%。高压处理后两个品种的植株叶片不同生长时期的平均光合色素含量均高于未处理的对照,在生长后期的衰老过程中高压处理植株剑叶的色素含量和PSⅡ光化学效率Fv/Fm下降速率较各自的未处理对照缓慢。高压处理后两个水稻品种的生物量和单株产量分别比对照提高了8%~27%及7%~14%。提出高压处理可能作为一种新的选育品种的方法。 相似文献
70.
生物质秸秆热重分析及几种动力学模型结果比较 总被引:42,自引:9,他引:42
利用热重分析在不同升温速率和氮气气氛下对两种生物质(玉米秸秆和稻秆)的热失重行为进行了研究。根据热重实验数据,采用四种利用热分析获取动力学参数的方法(Coats-Redfern法,Doyle法,最大速率法和分布活化能模型(DAEM)),计算生物质秸秆热分解反应活化能E、反应级数n及频率因子A,并进行比较。结果表明,采用不同的处理方法,得出的热分解动力学参数不同。利用Coats-Redfern法,玉米秸秆和稻秆在热解主要阶段(失重约5 w%~80 w%时)可由一段一级反应过程描述,升温速率10 K/min时活化能值分别为68.8 kJ/mol和70.0 kJ/mol。Doyle法和DAEM模型得到的结果较为接近,可以得到生物质热解过程中的活化能随失重率的变化曲线。生物质秸秆热解包含分子键能断裂的一系列复杂、连续反应过程。 相似文献