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21.
不同基因型对花生胚小叶植株再生的影响 总被引:1,自引:1,他引:0
以不同类型18个花生品种成熟种子的胚小叶为外植体,对不定芽诱导及植株再生进行了研究,旨在为花生遗传转化和离体诱变等提供培养方法。将胚小叶外植体培养在添加1 mg/L NAA和6 mg/L BAP的诱导培养基上,4周后转移到添加4 mg/L BAP的培养基上进行培养。结果表明,所有的供试品种芽点诱导率均高于60%,但5大类型间及品种间(62.2%~95.5%)存在显著差异,龙生型平均诱导率最高(87.2%),其次是珍珠豆型(81.5%),多粒型最低(63.1%)。将形成芽点的外植体转移到添加4 mg/L BAP的培养基上后,部分外植体从芽点上分化出不定芽,继续培养不定芽伸长并再生植株。植株再生率也存在显著性差异,最高的是珍珠豆型(83.5%~97.1%),最低是多粒型(14.8%~22.0%)。 相似文献
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穴盘移栽指铲式末端执行器苗钵基质抓取仿真与试验 总被引:5,自引:0,他引:5
针对针式末端执行器夹持移栽后穴孔内基质残留较多的问题,设计了一种指铲式末端执行器,通过增大指铲与苗钵基质的接触面积,减少穴孔内基质的残留。通过静力学分析找出末端执行器提取苗钵后基质残留的原因:基质间的最大内聚力小于由基质与穴盘间的粘附力和苗钵重力合成的总阻力时,苗钵出现破裂,基质塌陷。基于离散单元法,通过EDEM(Enhanced discrete element method)仿真分析了指铲式末端执行器对土壤基质的抓取过程,发现随着土壤基质内聚力的提高基质残留的现象得到改善;将基质配比和含水率条件作为主要影响因素,通过组合测盘试验测量在不同基质配比和含水率试验条件下的粘附力和内聚力变化,寻找内聚力大于粘附力的基质配比和含水率条件。试验表明,当相对含水率为60%、基质配比为6∶3∶1(泥炭∶蛭石∶珍珠岩)时,内聚压强和粘附压强的差值最大,在该条件下,指铲式末端执行器对劣质苗钵穴孔基质的平均剔净率达到70. 8%,优于其他作业条件,可剔除穴孔内大部分基质。 相似文献
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本研究通过盆栽试验于大豆R_5时期,在晴天(f)和阴天(c)条件下,对大豆叶运动与叶面受光的研究结果表明,大豆各方位的叶数(%),晴天时,西和西南高于东和东北;阴天时,东西水平线以南各方位叶数(%)大致相近。还看出,不论晴阴天时,东西水平线以南高于以北。大豆叶片倾斜方向,主、副倾角,晴天时的叶数(%)正向>负向;阴天时,相反。大豆叶片倾斜角度,主、副倾角,晴天时,正向>负向,阴天时,相反。大豆叶面受光,晴天群体光照强度处于20~30KLx,阴天4~6KLx,多数未达光饱和状态。从叶片分布方位,叶片倾斜方向、角度和叶面受光关系看,在晴天时,由于太阳高度和位置变化,直射光多,主、副倾角正向角度大。为充分利用光能,大豆叶由东南向西南作调位运动。本研究进一步证实了叶枕中钾的含量增高时对叶片直立和扭曲起调节作用。 相似文献
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The present study was conducted to investigate the genetic inheritance of morpho-physiological leaf traits in chickpea (Cicer arietinum L.). The experimental material comprised six generations, viz., two inbred parents, ‘T88’ and ‘Bold Seeded’, having contrasting leaf traits, and their derived F1, F2 and backcross of F1 to either parent (B1 and B2). The experiment was randomized complete block design with three replications. Genetic parameters were estimated by generation mean analysis using all the six generations. Data were collected on individual plants within each family just before flowering on leaflet area (LA), number of leaflets per leaf (LL), rachis length (RL), and leaflet density (LD), which was calculated as number of leaflets per unit length of rachis. A simple additive-dominance model was found to be adequate to describe the inheritance of LL and LA, while dominance × dominance (i.e. [1]) and additive × dominance (i.e. [i]) interactions were also significant for RL and LD, respectively. Improvement or seed yield per plant may result from selection for LA by improving both RL and LL. Leaflet area may be included in the ongoing selection schemes, as a supplementary trait to increase the speed of improvement in seed yield per plant. Lanceolate leaflet shape was observed to be monogenically dominant over obovate leaflet shape, and segregated independently from purple/white flower color. 相似文献
28.
ELOISA TERZO MARCO DI MARCELLO HESTER McALLISTER BRENDAN GLAZIER DANIELE LO COCO CHIARA LOCATELLI VALENTINA PALERMO PAOLA GIUSEPPINA BRAMBILLA 《Veterinary radiology & ultrasound》2009,50(4):416-422
In this work we investigated which mitral valve leaflet was most often involved in mitral valve prolapse with degenerative mitral valve disease and whether there was an association with breed, age, gender, or weight. Five hundred and thirty-seven dogs with mitral valve prolapse-degenerative mitral valve disease were assessed; the cross-breed dog was the most represented breed (248 dogs, 46.2%). Mitral valve prolapse was more common in male dogs, and the average age was 11.3±2.8 years. Prolapse of the anterior leaflet was present in 48.4% of dogs, prolapse of the the posterior leaflet in 7.1%, and bileaflet prolapse was present in 44.5%; this distribution is different than that typically found in humans. There was a significant correlation between severity of mitral regurgitation and severity of mitral valve prolapse or ISACHC class, and between severity of mitral valve prolapse and ISACHC class. There was no relationship between the particular affected leaflet(s) and severity of mitral regurgitation, severity of mitral valve prolapse, or ISACHC class. Our findings suggest that the susceptibility to the mitral valve prolapse-degenerative mitral valve disease is not confined to a specific breeds and that the specific leaflet prolapsing is different in dogs compared with humans. 相似文献
29.
《Southern Forests》2013,75(4):211-216
Phytophthora pinifolia causes the needle and shoot disease of Pinus radiata in Chile known as Daño Foliar del Pino. Although P. pinifolia is primarily a needle pathogen, there are concerns that it might be spread to new environments via the export of contaminated timber. In order to determine whether P. pinifolia can enter or persist in green sawn lumber, its presence in lumber produced from trees exposed to the pathogen for at least four years was examined. Green lumber produced from the infected trees, and green wood samples artificially exposed to P. pinifolia inoculum, were analysed by making extensive isolations on Phytophthora selective media. In addition, PCR was conducted using species-specific primers developed for P. pinifolia. Results of the study showed that the green sawn lumber taken from trees infected by P. pinifolia, or green lumber exposed in infected pine plantations, displayed no evidence of the pathogen surviving in this material. 相似文献
30.
农杆菌介导的花生遗传转化体系的优化 总被引:1,自引:0,他引:1
以花生胚小叶及其诱导形成的愈伤组织为转化受体,采用农杆菌介导法,通过评估外植体GUS基因瞬时表达率,优化花生遗传转化条件。结果表明,侵染液中添加表面活性剂2-氮吗啉乙烷磺酸(MES)150mg/L或烟草提取物0.5ml/30ml有利于提高胚小叶外植体GUS瞬时表达率;采用针刺法辅助农杆菌介导转化,其胚小叶外植体多点GUS瞬时表达率(29.1%)明显高于未针刺的对照(12.1%);利用愈伤组织作为转化受体,其多点GUS瞬时表达率高达70.1%。利用此优化体系进行花生遗传转化,获得的抗性苗2011年经嫁接、移栽于试验田,PCR检测获得了T0代转基因植株,2012年部分T1代植株也检测出目的条带。 相似文献