九○素解除杂交水稻包颈提高结实率的初探

近年来,杂交水稻制种“九二○”用量不断增加,但货源紧缺,价格昂贵,使制种田成本大幅度提高,随九二○用量增加,种子穗萌严重提高。目前国内外尚未发现有取代九二○(赤霉素)的药物报道。为降低成本,减少种子穗萌。我们在1990年应用新型植物生长调节剂——九○素,在水稻制种上进行了试验,取得良好的效果,现将初试结果报告如下:     

九○素解除杂交水稻苞颈提高结实率初探

近年来,杂交水稻制种“九二○”用量不断增加,但货源紧缺,价格昂贵,使制种田成本大幅度提高。随九二○用量增加,种子穗萌有提高的趋势。为降低成本,减少种子穗萌。我们在1990年应用新型植物生长调节剂九○素,在水稻制种上进行了试验,取得了良好的效果,现将初试结果报告如下:     

抗穗萌剂抑制杂交水稻种子穗发芽的初报

近年来,九二○植物调节素在杂交水稻中的应用,存在一个突出的问题是母株的穗发芽,一般年份穗发芽率为5～10%。遇到阴雨连绵天气则更易造成大量穗发芽。1989年浙江省早稻穗发芽达10～20%导致减产,不仅给收购工作、种子贮藏和浸种催芽增加了难度,而且严重影响种子质量和经济效益。为此,我们应用抗穗萌剂Ⅰ(水剂);Ⅱ(粉剂)进行抑制杂交水稻种子穗发芽的研究,取得初步效果。     

利用外源化学抑制物质控制杂交小麦不育种子的穗萌

本试验选用的化学抑制物质(30%的青鲜素和60%的抑制性有机酸)在小麦T型不育系盛花后20、24和28天进行田间小区1000、2000和3000ppm的喷施处理。所有处理均明显降低了早萌的程度,其中以用药时间盛花后24天,浓度为1000ppm的处理效果最好,穗萌率由16.17下降至1.87%,千粒重也略有提高,而且收获后的种子贮藏6个月发芽力超过对照水平。进一步提高处理浓度或盛花后20天、28天的各种浓度处理,早萌抑制效率、贮藏后种子发芽力都不及盛花后24天1000ppm的处理。抑制物质处理对控制赤霉病率亦有一定效果。     

杂交稻制种始穗期不同时刻喷施九二○对结实率的影响

杂交稻制种始穗期不同时刻喷施九二○对结实率的影响广西融水县种子公司韦松杂交稻不育系繁殖和制种技术中，适时适量喷施九二○对穗茎的伸长解除包颈，使之穗粒外露，增加授粉，提高种子产量有着十分重要的作用。在前几年已发现上午喷施九二０的效果好于下午喷施的。为此...     

“穗萌抑制剂”在杂交稻制种上的应用结果

1991年,浙江省10个县、市种子公司在杂交水稻种子成熟期,喷施了“穗萌抑制剂”试验。在制种田齐穗后10天,把药液喷在不育系上,对杂交稻种子在穗上发芽可起到明显抑制作用,但收获后1—2个月又可恢复正常发芽率。同时,喷施“穗萌抑制剂”后,还可以起到提高结实率,增加千粒重,提高制种产量。     

杂交水稻制种多元化学调控的研究——“九二○”(GA_3)施用量对种子产量和质量的综合影响

本试验首次系统地研究了不育系始穗期施用不同量“九二○”对制种产量和种子质量的综合影响。汕优6号和威优35两组合制种的结实率和产量,随激素用量增加而提高,至12克/亩或15克/亩的用量时达最高;此后加大用量结实率和产量反开始下降。F_1种子千粒重与GA_3的用量呈线性反相关。“九二○”田间喷施不育系,将引起F_1种子耐藏性的下降,贮藏9个月后的种子活力和生活力与对照相比有明显下降;“九二○”用量愈大,下降幅度愈明显。作者认为,为提高制种产量而使用高剂量“九二○”,是目前杂交稻播种时品质较差的主要原因。     

改进九二O喷施技术提高母本透颈率

九二○在水稻制种上的应用十分普遍,且必不可少。它具有促进穗下节间伸长,使母本（水稻不育系）穗透颈等特殊作用。但不同用量、不同喷施方法所产生的效果不同。为了提高九二○在水稻制种上的应用效果,我司参照外地先进技术,结合近几年来的实践经验,对九二○喷施从技...     

“九○”素在杂交稻制种上的应用效果

近年来杂交水稻制种“九二○”用量不断增加,但货源紧缺,价格昂贵,使制种田成本大幅度提高,并有随“九二○”用量增加,种子穗萌发严重的趋势。为降低成本,减少种子穗萌发,我们采用新型植物生长激素——“九○”素在杂交稻制种上进行了试验。     

杂交稻种穗上发芽抑制方法及休眠特性研究

杂交水稻高产制种技术的推广应用,特别是提高单位面积种植密度,大剂量使用九二○及增效剂等促进异交结实的措施,产生了一个亟待解决的问题,即穗上发芽。为了对现有药剂进行比较筛选,研究种子休眠特性和寻找打破种子休眠的方法,特设计本试验。 1 材料和方法 1.1 田间试验地点和品种:选择永安市烟后作威优77制种和浦城县中稻汕优78制种两种类型田块,要求田间土壤肥力均匀、父母本生长平衡一致。 1.2 小区设计与处理方法:①穗萌抑制剂Ⅰ(浙江农业大学制),每亩60克兑水25公斤,隔天喷施2次;②穗萌抑制剂Ⅱ(湖南省种子公司制),每亩     

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.