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131.
132.
农杆菌介导的马铃薯试管薯遗转化体系的优化及反义class Ⅰ patatin基因的导入 总被引:14,自引:0,他引:14
用两个马铃薯栽培品种“鄂马铃薯3号”和“甘农薯2号”的试管薯为供体材料,建立了一种农杆菌介导的简单、快速和高效的遗传转化系统。在含有75mg/L卡那霉素的选择培养基上,2~3周可产生抗性芽,4~5周获得完整的转基因植株。筛选出了试管薯遗传转化的优化条件,特别是在再生培养基中加入2mg/L玉米素,两个品种的转化频率分别高达45.5%和43.9%。周期短(4~5周)、一步培养和转化频率高,使该转化体系能够广泛用于马铃薯转基因的研究。用含有反义class Ⅰ patatin基因的表达载体pBSAP转化两个品种,共获得120株卡那霉素抗性植株。PCR、PCR-Southern和Northern杂交分析证明,此反义基因已整合到马铃薯基因组中并在转基因植株中正常转录。反义基因的表达导致部分转基因植株的试管结薯株率和单株结薯数降低。结果表明,该class Ⅰ patatin基因可能参与了块茎形成的调控。 相似文献
133.
通过根癌农杆菌介导法将甜菜碱醛脱氢酶(BADH)基因导入马铃薯栽培品种甘农薯2号, 经PCR、Southern杂交和Northern杂交证明BADH基因已整合到马铃薯基因组中并在转基因植株中转录和表达。测定表明对照植株没有BADH酶活性, 各转化株系在胁迫前后BADH酶活性近似, 在2~11 U之间。BADH酶活性与叶片的相对电导率呈一定的负相关(y= –3.7738x+57.083, r=0.989**)。在NaCl和PEG胁迫下, 转基因植株生长正常, 株高比对照提高0.41~1.00 cm, 单株重量比对照增加10%~35%, 说明外源BADH基因的导入提高了马铃薯植株对干旱和盐碱的抗性。 相似文献
134.
马铃薯新品种试验与利用分析 总被引:1,自引:0,他引:1
福建省种子总站组织安排了坝57、坝58、鄂马铃薯5号等8个马铃薯新品种在福州、泉州等7个点进行三重复试验,试验结果表明,不同品种间产量存在极显著差异,品种与地点互作也存在极显著差异。坝58、闽薯1号、中薯3号、坝薯8号等品种产量、农艺性状等表现突出,可进一步加大试验力度。 相似文献
135.
Climate change effects caused by an increasing concentration of CO2 and ozone represent an issue of major concern both for scientists and policy-makers. In a concerted program funded by the Commission of the European Union, a European network of experiments (in open-top chambers (OTC), and free air carbon dioxide enrichment systems (FACE)) and modelling was carried out to investigate the effects of increasing atmospheric CO2 and ozone concentrations, under different climatic conditions, on potato (Solanum tuberosum L. cv. Bintje). This contribution describes the experimental network and the standard protocol set-up for the assessments that served to improve and to validate process oriented potato growth simulation models leading to scenarios of future productivity of potato in Europe. 相似文献
136.
A. Hacour J. Craigon K. Vandermeiren K. Ojanper H. Pleijel H. Danielsson P. Hgy J. Finnan M. Bindi 《European Journal of Agronomy》2002,17(4):257-272
This paper describes the effects of elevated CO2 (550 and 680 μl l−1) and O3 (60 nl l−1 O3 as an 8 h mean), alone or in combination, on canopy development and senescence in potato (Solanum tuberosum L. cv Bintje) across a range of European agro-climatic conditions. The assessments were made within the European CHIP project (CHanging climate and potential Impacts on Potato yield and quality) that was conducted for two growing seasons (1998 and 1999) in free air CO2 enrichment systems (FACE) and open-top chamber facilities (OTCs) at seven European sites. A comparison of chambered and unchambered experimental plots was included to examine the effects of chamber enclosure. Phenological growth stages, plant height, leaf area index (LAI) and the number of green and yellow leaves were recorded non-destructively throughout the growing season and by a destructive intermediate harvest at maximum leaf area (MLA). In the dynamic growth analysis CO2 and O3 effects were studied over three developmental stages: canopy expansion, full canopy and canopy senescence. Chamber enclosures promoted potato crop development (taller plants, more leaves) during the initial growth stages and led to a faster decline of LAI and a higher number of yellow leaves. The growth in ambient plots varied between sites and seasons, as did the scale of the treatment responses. Despite the large background variation, some overall treatment effects could be detected across all sites. Both levels of increased CO2 reduced final plant height in comparison to ambient concentrations, which indicates a premature ending of the active plant growth. At the stage of full canopy and crop senescence the average number of green leaves was significantly (P<0.05) decreased by 680 μl l−1 CO2 (OTC experiments) and LAI showed the same tendency (P=0.07). As there was however no indication of a decreased leaf formation during initial growth and at full canopy, this must have been due to an earlier leaf fall. In the FACE experiments LAI had already began to decline at the stage of full canopy at 550 μl l−1 CO2 but not in ambient CO2 (DAE×CO2, P<0.05). These observations strongly indicated that elevated CO2 induced a premature senescence during full canopy. O3 did not have an overall detrimental effect on crop development during initial growth nor at full canopy, but did induce a faster reduction of LAI during crop senescence (DAE×O3, P<0.05). Final plant height was not affected by O3. There were few CO2×O3 interactions detected. There was a suggestion (P=0.06) that O3 counteracted the CO2-induced decrease of green leaves at full canopy, but on the other hand during crop senescence the decline of LAI due to elevated O3 was faster at ambient compared to elevated CO2 (P<0.05). These responses of canopy development to elevated CO2 and O3 help to explain the treatment responses of potato yield within the CHIP project at sites across Europe. 相似文献
137.
We have used 19 SSR markers to fingerprint 41 local potato cultivars from 10 locations of Tenerife Island. These varieties represent relicts of the early introductions originating from South America and have been characterised previously morphologically and ecophysiologically. The SSR primers generated a varying degree of polymorphisms. A total of 67 alleles were observed, 12 of them were present in all cultivars. Several accession and group specific alleles were detected. Similarity coefficients were computed from the molecular data and cluster analyses were performed. Generally, cultivar groups with identical or related common names showed the same SSR patterns or clustered closely together. According to the molecular patterns misleading or confounded names were evident for four accessions. The dendrogram clusters were generally in good agreement with previous classifications of the accessions as Solanum tuberosum subsp. andigena, S. tuberosum subsp. tuberosum and Solanum chaucha genotypes. However in four cases the molecular patterns showed discrepancies with previous species assignments suggesting the need for a more detailed and comparative study of these accessions. 相似文献
138.
营养与株型调控对雾培马铃薯的结薯生理影响 总被引:3,自引:0,他引:3
本研究采用3套营养液配方与3种株型调控措施探讨了不同马铃薯(Solanum tuberosumL.)品种的结薯生理效应。结果表明:不同营养液配方对雾培马铃薯的“源流库”皆存在一定的影响;采用以前期最小、结薯期最大的N/K和NH4 -N/NO3--N比值的A2营养液,对植株的光合势、叶绿素含量、根系活力、匍匐茎数、总薯数、总薯重以及后期末茎叶鲜重与干重等的增长刺激作用最大,其中又以“CIP24”品种的结薯性能最好;下放植株、喷施矮壮素和剪尖处理的不同组合均能使“CIP24”品种在A2营养液下增加光合势,降低株高,增加鲜重和增大根系体积。 相似文献
139.
试验分别在甘肃省景泰县、内蒙古自治区达拉特旗和河北省沽源县3个马铃薯生产基地进行,在基地常规N、P2O5、K2O肥施用量分别为300、345、375kg/hm2的基础上,研究改变磷、钾、氮肥用量对马铃薯营养状况、块茎产量以及土壤养分的影响。试验结果表明,氮、磷、钾肥用量分别从N300、P2O5345、K2O375kg/hm2降低到180、180、225kg/hm2,对植株干物质累积量没有显著影响,3个基地都呈相同的趋势;3个基地不同处理的块茎产量也没有显著性差异。因此,在试验条件下,氮、磷、钾肥用量和比例为180-180-225的施肥处理,其经济效益较高。施肥对土壤养分含量有较大的影响,特别是磷肥,当施用磷肥后,土壤速效磷含量显著提高,而且主要存在于表层土壤(0 ̄20cm),这说明缺磷土壤通过施用磷肥,可提高土壤有效磷水平。 相似文献
140.
马铃薯试管薯诱导影响因子的研究 总被引:3,自引:1,他引:3
以马铃薯品种大西洋脱毒试管苗为材料,研究了切段年龄、温度、激素、光照对马铃薯试管薯诱导的影响,在此基础上,进一步研究了蛭石覆盖茎节代替黑暗条件的不同培养方式对马铃薯试管薯诱导的影响。结果表明,结薯与切段的年龄有关,用培养100 d左右的苗即老的切段、白天25℃,夜间18℃的变温、培养基中添加激素6-BA浓度为2.5~5.0 mg/L时,试管薯诱导率高;在上述条件下,将蛭石灭菌后按每瓶30 ml直接倒入原来的培养瓶覆盖试管苗下部茎节2~4节,能够使覆盖茎节处快速生出匍匐茎,最终形成块茎,平均单株结薯1.9个,大大提高了试管薯诱导率。 相似文献