水稻耐低磷机理的初步研究

以耐低磷品种大粒稻和汕优63、低磷敏感品种新三百粒和沪占七为材料.测定0.5 mg/L(P)和10 mg/L(P)两种磷水平下水稻根系形态、氧化力、呼吸速率、动力学参数、丙二醛含量、酸性磷酸酶活性(APA)的品种间差异.实验表明,0.5 mg/L(P)时,大粒稻和汕优63根长分别比CK(10 mg/L)下降了15.2%和22.0%,根体积分别下降了25.2%和22.2%,而沪     

超高产水稻生育后期剑叶光合

笔者研究了黑龙江省第一积温带5个产量不同的主栽品种生育后期剑叶叶绿素含量、净光合速率和RuBP羧化酶活性变化规律.结果表明:超高产品种生育后期的剑叶叶绿素含量、光合速率和RuBP羧化酶活性均高于常规品种,品种间差异显著.因此,将剑叶生育后期叶绿素含量、净光合速率和RuBP羧化酶活性的变化研究,作为寒地粳稻高光效育种和超高产育种中的一项措施是可行的.     

超高产水稻生育后期剑叶光合生理特性变化的研究

笔者研究了黑龙江省第一积温带5个产量不同的主栽品种生育后期剑叶叶绿素含量、净光合速率和RuBP羧化酶活性变化规律。结果表明：超高产品种生育后期的剑叶叶绿素含量、光合速率和RuBP羧化酶活性均高于常规品种,品种间差异显著。因此,将剑叶生育后期叶绿素含量、净光合速率和RuBP羧化酶活性的变化研究,作为寒地粳稻高光效育种和超高产育种中的一项措施是可行的。     

氮肥水平对杂交稻汕优63剑叶光合速率和RuBP羧化酶活性的影响

用低氮(LN)、中氮(MN)、高氮(HN)盆栽土培的杂交水稻汕优63为材料,测定其剑叶的光合速率、RuBP羧化酶含量及活性、可溶性蛋白和叶绿素含量的变化.结果表明:随着氮水平的提高,叶面积增大,气孔密度减少,RuBP羧化酶活性和光合速率增加.随着叶龄的增加,三个不同氮水平的叶片中RuBP羧化酶蛋白下降均先于可溶性蛋白的下降;HN组的光     

低磷胁迫对不同水稻品种根系形态和养分吸收的影响

以耐低磷品种大粒稻、莲塘早3号和低磷敏感品种沪占七、新三百粒为材料，采用砂培，测定常磷（10 mg/L）和低磷（0.5 mg/L）两个磷水平下，根系形态、同化物分配、矿质元素吸收、离子吸收耗能的品种差异。实验结果表明，低磷胁迫下，耐低磷品种的总根数、总根长、总根表面积、侧根长、侧根数及侧根密度均明显增加，而低磷敏感     

烟草光合作用对低温的响应

研究了低温对烟苗叶片光合特性的影响。用CIRAS-1光合系统测定了各项光合指标,结果表明：（1）在16℃,8℃,3℃条件下,净光合速率(Pn)、表观量子效率(AQY)、羧化效率(CE)、RuBP最大再生能力随温度的降低显著下降,在8℃,3℃条件下发生了低温光抑制现象;低光强下,温度对Pn的影响小,温度对Pn的效应随光强的增大而增大,当光     

低钾胁迫对水稻叶片光合功能的影响及其基因型差异

经大量的水培筛选后,选用对低钾胁迫敏感程度差异较明显的3种水稻基因型进行大田试验,探讨低钾胁迫下水稻钾高效基因型的有关生理基础,试验表明:低钾胁迫破坏水稻光合器官,导致叶片净光合速率降低,气孔阻力增加,叶片RuBP羧化酶活性降低,因此低钾胁迫引起水稻大幅度减产.水稻不同基因型对低钾胁迫的抗性存在差异,钾高效基因型     

低温胁迫对茄子幼苗叶片光合特性的影响

以茄子702幼苗为试材,研究了低温胁迫对茄子幼苗光合特性的影响.结果表明,低温胁迫下,茄子幼苗的叶绿素含量、叶绿素a/b、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、光饱和点(LSP)、光饱和光合速率、表观量子效率(AQY)、CO2饱和点(CSP)、羧化效率(CE)和RuBP最大再生速率均下降;光补偿点(LCP)、CO2补偿点(CCP)均上升;胞间CO2浓度(Ci)先降低后升高.以上结果表明,低温胁迫伤害了茄子幼苗的光合机构.     

低温胁迫对茄子单性结实材料生理特性的影响

为有效评价茄子单性结实材料,用于新品种的选育应用,以单性结实材料D-11和非单性结实材料00-13为试材,在人工可调环境下,研究低温胁迫(5℃)对茄子幼苗生理特性的影响。结果表明,低温胁迫下,单性结实材料冷害指数低,膜脂过氧化产物丙二醛含量(MDA)少,抗冷性强;随胁迫时间的延长,幼苗叶片的净光合速率(Pn)、光饱和点(LSP)、光饱和光合速率、表观量子效率(AQY)和CO2饱和点(CSP)、羧化效率(CE)、RuBP最大再生速率等均下降;而光补偿点(LCP)、CO2补偿点(CCP)具有上升趋势;胞间CO2浓度(Ci)先升高后降低。实验表明,低温胁迫主要影响茄子幼苗光合机构的活性,单性结实材料的抗冷优势明显,光合参数变化幅度小。     

临界低温弱光对黄瓜光合特性及其酶变化的影响

在连续4d单一临界低温15℃／8℃(昼／夜)和临界低温弱光下对黄瓜的光合性状及其酶变化进行了测定。结果表明：在单一临界低温下黄瓜各品种叶绿素含量、叶绿素荧光量子产额(yield)、光合速率显著降低，而在临界低温弱光下，叶绿素荧光量子产额上升后又下降，叶绿素含量降低速度变慢，反映碳同化酶活性的M峰值减弱，RuBp羧化酶活性显著降低后又有回升，处理过程中电解质渗漏率降低。处理4d时黄瓜光饱和点显著降低。温度-光合速率曲线变化表明，黄瓜的光合适温发生偏移，表现出低温适应性，品种间以新泰密刺表现出较强的耐低温性。     

冷冻干燥速溶蛋花汤的加工技术

介绍了运用冷冻干燥技术进行速溶蛋花汤的加工,研究了生产工艺、特点以及影响产品质量的主要因素。试验表明,采用冷冻干燥技术加工的速溶蛋花汤,具有营养丰富、风味独特、方便快捷等特点。     

Measuring of Quantity of Matter-mass and the Measuring of Inertia of Matter-momentclm

A new definition of inertia,i.e. the momentum is the measuring of inertia of matter, is proposed. The article through and etc., subjects, the correctness of the new notion of inertia:The monentum is the measuring of inertia has been demonstrated, and the unsolved contradictions of the traditional definition of inetia. And the mass is the measuring of inertia has been revealed.     

香蕉遗传转化方法研究进展

香蕉是热带亚热带发展中国家重要的粮食作物和碳水化合物来源。但近年来,香蕉生产受到严重的病虫危害。大多数香蕉栽培品种是三倍体,生长周期长,而且不孕。由于没有种子,给繁殖和育种带来一定的困难。遗传转化技术的发展为香蕉品种的改良提供了一种有效的手段。香蕉的遗传转化方法有电激法、基因枪法、农杆菌介导法等。农杆菌介导法的应用是香蕉品种改良的一个重大突破。香蕉遗传转化的外植体也发展到多种,有原生质体,胚性细胞悬浮系,分生组织,以及横切薄片等。近几年,随着分子生物学的发展,出现了转化效率更高,重复性更好的香蕉遗传转化技术。如农杆菌和基因枪结合法,离心辅助农杆菌介导法、真空渗透技术等。这些新技术新方法的出现,必将推动香蕉产业高速发展。     

壳聚糖对石榴果汁澄清效果的影响

利用壳聚糖的絮凝作用对壳聚糖在甜石榴汁澄清中的应用效果进行了研究,试验结果表明,壳聚糖用量为0.3g/L、澄清时间为60min、温度为35℃时,甜石榴汁透光率可达85%以上,且通过对壳聚糖处理前后可溶性固形物、总酸、VC等营养成分含量的比较,确定以上工艺参数为甜石榴汁澄清的最佳选择。     

新疆布尔津县土地利用格局特征研究

基于RS与GIS技术,利用景观生态学理论及景观格局指数对布尔津县土地利用现状进行定量分析。结果显示为：（1）布尔津县以草地、林地为主要景观类型,镶嵌着耕地、水域等景观类型。（2）四个分区（即高山区、丘陵区、平原区、荒漠区）的林地资源组成差异明显,耕地、居民、交通及工矿用地集中分布在丘陵区和平原区（3）从各项指数来看,高山区的多样性指数较低;平原区是受人文因素最多的区域,景观优势度低,各种土地利用类型比例差异不大,有利于生态可持续发展,但要合理的开发利用;荒漠区生态环境相对脆弱,要加强生态环境的保护与改善。通过该研究对布尔津县的土地利用现状作一个了解,为该县乃至整个地区的景观规划和可持续发展战略提供科学依据。     

酸枣幼根原生质体的制备

以生长6～9 d的酸枣种子幼根为试验材料,0.7 mol·L-1甘露醇作为渗透压稳定剂、pH值5.5～6.0、28℃恒温水浴条件下,以光学显微镜观察的水解总时间、初始产生原生质体的时间、原生质体产量及细胞碎片量为指标,研究通过酶水解来制备酸枣幼根原生质体的方法.结果表明,在含1％果胶酶+4％纤维素酶R-10+3％纤维素...     

影响核桃贮藏品质因素的分析

介绍了几种核桃贮藏方法,综述了影响核桃贮藏品质的几个主要因素,以及针对上述影响因素提出若干解决对策.     

Efficiency of water use of early plantings of sunflower

Rain fed crop production in Mediterranean environments depends to a large extent on strategies that avoid the intense summer drought. Early plantings of sunflower have given consistently higher yields in such environments, but the basis for such yield increases has not been explored. We conducted two field experiments at Cordoba (Spain) to investigate the effects of an early and a late planting date on the components of water-limited crop productivity; namely, water use (T), water use efficiency (TE) and harvest index (HI) of sunflower. The results were generalized by simulating rain fed sunflower yields, under early (1 January) and late (15 March) plantings, for a 25-year period with the aid of a simulation model of the Ceres type (OILCROP-SUN) which has been validated in Cordoba. Experimental seed yields of early plantings in 1989 and 1996 were 2.0 and 3.0 t ha⁻¹, while late plantings yields were 1.3 and 2.4 t ha⁻¹, for the 2 years. Average simulated yields were 2.7 ± 1.1 and 1.9 ± 0.7 t ha⁻¹ for early and late plantings, respectively. For the 2 years, T of early plantings was higher than that of late plantings, but the response of TE and HI to planting date was not the same in the two experiments. In the simulation exercise, T and TE of early plantings were consistently higher than those of late plantings, while there were no differences in the HI for the two planting dates. We conclude that early plantings of sunflower increase rain fed yields by increasing both T and TE, while the impact of planting date on HI very much depends on the crop water stress pattern, which is quite variable from year to year even in the predictable Mediterranean environment.     

Establishment of High-frequency Regeneration System of Explants of Alfalfa

The cotyledon and hypocotyl of eight varieties of alfalfa( Medicago sativa L. )are used to study the effect of different cultivation procedures and genotypes on embryogenic callus and embryoid induction,plant development and transplant of alfalfa.The varieties of alfalfa with high embryoid induction rate and high differentiation rate are screened. A high frequency regeneration system for alfalfa tissue culture is established:which is benifical to the gene transformation of alfalfa.     

Laboratorial Method of Determining Limit of Yielding of Material

Based on the relation between the incipient yield pressure and the limit of yielding in cylinder according to the elastic disabled rule, a laboratorial method of determining limit of yielding of material is designed and a set of experimental data were gained by the method. The incipient yield pressure of the cylinder is gained by analyzing the experimental data, and then the limit of yielding is gained. The laboratorial method has a good reliability as the experimental value has a little error to the theory value. It has a definite engineering signification and theory value to research the mechanical capability of material and the disabled rule of high pressure vessel.