云南大叶茶与汝城白毛茶杂交后代的RAPD亲子鉴定

应用随机扩增多态性DNA (RAPD)分子标记技术 ,对云南大叶茶 (C .sinensis)与汝城白毛茶 (C .ptilophylla)进行人工杂交所获得的F1代植株进行了亲子鉴定。结果表明 ,13个随机引物在第 1个杂交后代( 1F1)中共扩增出 80条RAPD谱带 ,其中 79条能在双亲中检出 ,另 1条为 1F1自身的特异带 ,卡平方检验表明在 1F1中扩增出的谱带数与亲本中各对应位点所显示的谱带数之间没有显著差异 ;在第 2个杂交后代( 2F1)中共扩增出 75条谱带 ,在第 3个杂交后代 (     

浙江部分茶树良种的RAPD分子鉴定

用随机扩增多态性DNA（RAPD）技术对目前浙江省推广的浙农121，迎霜，福鼎大白茶，浙农139等10个优良品种进行分析，共扩增到97条RAPD谱带636个位点，平均每个引物扩增RAPD谱带和位点约8．1条53个位咪，平均每个品种为9．7条63．6个，其中呈现出多态性的谱带72条，多态性占总带数的74．2％，供试品种经扩增产生5条－12条不等的谱带，说明引物的不同，RAPD标记谱带也随着产生差异，引物S16能在各品种扩增后产生特异性的分子标记，可以用来鉴定这些茶树品种，10个品种间遗传距离变化范围在0．3358－0．5774之间，平均为0．4732，其中浙农139和浙农113之间亲缘关系密切，类平均法聚类结果表明，这10个茶树品种可分成A、B、C三个类群。     

芸芥种质资源的遗传多样性研究

用100个随机引物对18份芸芥材料的基因组DNA进行扩增,结果有10个随机引物得到了稳定一致的RAPD谱带,每个引物扩增出2～17条谱带,共扩增出91条谱带.采用UPGMA法对扩增出的谱带进行遗传聚类分析,在遗传距离(D)=0.1333处,将18个芸芥材料分为2类8组,揭示了芸芥种质资源的遗传多样性.     

小麦新品种川农16的分子鉴定

为有效利用基因资源,应用RAPD、STS和SSR等3种分子标记对小麦新品种川农16及其亲本和对照品种进行了分析鉴定。结果表明,供试材料在DNA水平上存在多态性。3种标记均能揭示川农16与对照品种在DNA水平上的遗传差异。川农16与双亲在相同位点的同源性也有差异,电泳带型表现出同父、同母、综合和不同于亲本的新带型等多种类型。其中,RAPD分析中共有22个引物(32．8％)和68条(42．8％)带纹、STS分析中有6个引物(50％)和21个引物一酶组合(17．5％)、而SSR分析中有11个位点(32．4％)能揭示材料间的差异。与RAPD和STS标记相比,SSR标记结合聚丙烯酰胺凝胶电泳和银染技术更适合于绘制小麦指纹图谱。     

分子标记技术在玉米和高粱品种分析中的初步应用

以玉米丹2100和高粱辽杂10号的可见叶片为材料,应用RAPD筛选技术,对玉米、高粱基因进行分子标记.主要结果如下:(1)对玉米丹2100和高粱辽杂10号叶片总DNA提取纯化的方法进行优化,确定提取总DNA的最佳方法.即CTAB法.(2)初步建立了玉米丹2100和高粱辽杂10号RAPD反应体系,并确定了RAPD反应体系中最佳的引物种类及PCR扩增的最佳反应条件,获得了稳定高效的RAPD扩增结果及多态性较好的DNA.(3)应用RAPD技术筛选14个随机引物,共扩增出45条谱带.A2、G4、Y13分别扩增出3条差异谱带分别为OPG-04800、OPA-02450、OPY-13500.     

利用RAPD进行茶组植物遗传多样性和分子系统学分析

对张宏达系统山茶属茶组植物24种、变种的遗传多样性和分子系统学进行了RAPD分析。从冬梢中获得了高质量和高得率的基因组DNA, A260/A280平均为1.71,平均得率为331μg/g鲜重。从Operon技术公司的61个十聚体随机引物中筛选出15个用于茶组植物的RAPD扩增,在所扩增得到的107条可重现谱带中(平均7.1条/引物)有102条(平均6.8条/引物)是多态的,多态性程度是95.3%。每个引物扩增的谱带数在211条之间,相对多态性频度在0.04—0.96之间,不过总平均多态性频度只有0.30,     

咖啡种质资源DNA指纹图谱的构建

选用4份咖啡种质资源为材料,对S1-S100共100个RAPD引物进行筛选,选出多态性好的引物10个。利用这10个RAPD引物对28份咖啡资源进行扩增,共获得86条带,平均每个RAPD引物扩增出8.6条带,多态性谱带74条,多态性条带比率为86.0%。结果表明：供试咖啡种质资源遗传多样性较丰富;10个多态性好的RAPD引物中S8的鉴别效率最高,能将全部供试材料全部区分开,通过整合软件录入如所属种类、种质名称、采样地点、引物、RAPD-PCR 扩增数据以及电泳图片等相关信息,形成指纹图谱二维编码,构成咖啡种质资源的DNA指纹图谱,为咖啡种质资源品种权益保护及分子身份证构建奠定了基础。     

花生序列相关扩增多态性(SRAP)标记的研究

研究了分属3个市场型的10个中国花生栽培种的序列相关扩增多态性（SRAP）。结果表明，SARP技术可以揭示花生栽培种的遗传差异。在所试验的51对SRAP引物中，2对只获得了单态性条带，其余49对总共产生了1087条带，其中503条（46．27％）为多态性带，每对引物组合平均获得22．18条总带、10．26条多态性带。在这49对引物组合中，总带数和多态性条带的数目分别为7～63和2～32条。 10个花生栽培种间的简单匹配相似系数为0．7712～0．9250不等，根据SRAP指纹图谱进行聚类分析可将这10个品种分为4类。另外一项采用作图亲本24-3和B4的研究中，40对SRAP引物共计获得了160条多态性带。本研究为花生品种鉴定和遗传研究提供了新的DNA分子标记技术手段。     

用微卫星DNA标记建立宁2A的指纹图谱

 应用筛选出的4对SSR引物，建立了杂交水稻不育系宁2A 以及宁2B的DNA指纹图谱，结果表明，宁2A/B 特异性的 SSR指纹是引物RM206的谱带1和引物RM224的谱带1。通过与其他广泛应用的杂交水稻亲本材料的遗传关系分析，发现宁2A/B具有籼稻的遗传成分，从而在分子水平上解释了该材料与籼稻亲和性较高的原因。     

福建余甘子遗传资源的RAPD分析

以福建省34份余甘子遗传资源为材料,采用20个具特异扩增的多态性引物对福建省34份余甘子基因型进行扩增,20个引物,在34份供试材料中总共扩增出259个位点,且均是多态的,多态性程度达100%,平均每个引物扩增12.95个位点。同时,获得了19个引物对23份材料扩增的RAPD特征标记47个,17个引物在36对材料上共扩增出36个共享特征RAPD标记;采用ED(欧氏距离)法进行RAPD标记的聚类分析则可将福建34份余甘子遗传资源明显划分为惠安余甘和莆田余甘两大类。各供试材料之间的遗传距离范围为0.00～1.00,其中栽培品种与野生资源之间遗传距离在0.43～1.00之间;莆田余甘资源与惠安余甘资源之间遗传距离为0.27～0.99。     

SILAGE AND MILK PRODUCTION. A COMPARISON BETWEEN A DIPLOID AND A TETRAPLOID RYEGRASS

Two grass silages made in May and two made in August were compared in a 16-week winter-feediag experiment with 12 Ayrshire cows. The silages were fed ad lib. with a supplement of barley and groundnut cake. One of the silages made ia May and one made in August consisted of S24, a diploid variety of perennial ryegrass, and the other two of Reveille, a tetraploid variety of the same species. The silages made from Reveille had a higher content of lactic acid and a lower pH than those made from S24. The contents of digestihie organic matter in the silage DM made in May and August were 71.9 and 63.2%, respectively, for RevelUe and 68.7 and 60.9% for S24. Silage and total DM intakes were higher in the treatments where Reveille silages rather than S24 silages were fed. The mean daily milk yields from cows fed on the silages made in May and August were 39.6 and 34.5 lb (18.0 and 15.7 kg), respectively, for Reveille, and 38.0 and 34.1 lb (17.3 and 15.5 kg) for S24. The solids-not-fat (S.N.F.) and the crude protein contents of the milk averaged 8.64 and 3.29%, respectively, for Reveille, and 8.56 and 3.22% for S24. It is concluded (hat the silages made from Reveille were superior to those made from S24 as a feed for dairy cows.     

A LINEAR PROGRAMMING MODEL OF A HIGH-TEMPERATURE GRASS-DRYING ENTERPRISE

A linear programming model of a high-temperature grass-drying enterprise is described. From information about seasonal crop response, area of crop available and management constraints, the model determines the harvesting schedules which give greatest returns, less costs, from the enterprise over the season. This information can be used to examine the effects of long-term strategic decisions or to evaluate economically data on new crops from field experiments. For example, assuming a fixed cost of λ70,000/year for a high-temperature grass-drying installation and what is considered to be reliable input data for 1972, the returns less costs for optimum harvest schedules from different areas or crop varieties are:

A MANAGEMENT STUDY OF A BIRDSFOOT TREFOIL STRAIN TRIAL

A study of birdsfoot trefoil ( Lotus corniculatus L.) variety trial management was conducted with three variables, variety, stubble height and harvest date. The range in maturity for the three varieties used was 12-14 days. All plots were harvested thrice per season. The harvest dates for the two management regimes imposed differed by about two weeks for the first cut, by about one week for the second and were identical for the third cut. Stubble heights were two and six inches (5.08 and 15.24 cm).
Late-cut material outyielded that cut early, but suffered more winter damage. Material cut at a stubble height of two inches (5.08 cm) outyielded that cut at six inches (15.24 cm), but it also suffered more winter-killing. The ranking of varieties varied with management.
Alternative management schemes, designed to provide maximum yields and survival consistent with good-quality forage, are proposed and discussed.     

Development of A dormancy release technology: A review

Tuber dormancy can be released immediately in many commercially important potato cultivars by brief treatment (1-2 days) with bromoethane (BE) vapor at room temperature. The development of a large scale technology for BE application and safe removal through a capturing technique is necessary for successful application of this dormancy release method. Ideally, BE treatment of seed tubers would occur in a closed environment that would capture BE vapor in an unaltered form and allow controlled release for treatment of subsequent tuber lots. Results of screening studies for adsorbents indicate that the medium capacity activated carbon adsorbent, YAO has: i) a high capacity for BE; ii) a low capacity for water; and, iii) adsorbs and de-adsorbs BE quickly and easily. A plausible design of a large scale, dormancy release facility is presented. The proposed facility should meet present goals of the seed potato industry in an environmentally responsible manner.     

A COMPARISON BETWEEN A PADDOCK SYSTEM AND A 'WYE COLLEGE' SYSTEM OF GRAZING FOR MILK PRODUCTION

Two grazing systems, a paddock system and a ‘Wye College’ system, were compared in two 20-week experiments nsing 16 and 20 spring-calved Ayrshire cows in 1970 and 1971, respectively. A sward of S23 perennial ryegrass was used, and an average of 342 kg N/ha (305 lb N/ ac) was applied per annum. The paddock system had 28 separate paddocks; one paddock was grazed each day in rotation and occasionally topped in mid-season. The Wye College system had 4 plots of equal size and the cows were offered 1/7 of one plot each day; no back fence was used and surplus herbage was neither cut nor topped. The stocking rate on hoth systems was 1 cow per 0.20 ha (0.49 ac) in 1970 and per 0.16 ha (0.40 ac) in 1971. The mean daily milk yields per cow on the paddock and the Wye College systems were 16.2 and 15.3 kg (35.7 and 33.7 lb), respectively, in 1970; and 18.1 and 18.4 kg (39.9 and 40.6 lb) in 1971. The average annual output of milk was 13,500 and 13,150 kg/ha (1200 and 1170 gal/ac) on the paddock and Wye College systems, respectively. The fat and solids-not-fat (S.N.F.) contents of the milk were not significantly affected by the grazing system. It is concluded that the Wye College system was as effective as the paddock system in producing a high output of mUk per ha, but at a lower cost and with far fewer management decisions.     

广东育成无垩白软型优质籼稻不育系粤丰A

粤丰Ａ是由广东省农科院水稻研究所于1998年育成的国内第一个无垩白、低直链淀粉含量(14.3%)、软胶稠度(92ｍｍ)、低糊化温度(碱消值7.0)和香味浓的特优籼型三系不育系。该不育系千株群体不育株率为100%,花粉不育度为99.99%,柱头外露率达88.1%,稻瘟病全群抗性比达中抗水平。2000年10月在广州通过了由来自扬州大学、国家水稻改良中心、国家杂交水稻工程技术研究中心等单位著名专家的技术鉴定。专家组一致认为该不育系综合性状优良、不育性稳定、配合力强、异交结实率高、品质改良有重大突破,研究成果达国内外领先水平;其投入生产应用对推动我…