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61.
对杂交后代进行杂种的真实性鉴定是杂交育种成功的前提。AhMITE1转座子标记是一类基于PCR的分子标记,其在花生中扩增的产物片段差异大,多态性强,采用琼脂糖凝胶电泳即可区分。本研究用7对多态性转座子引物对6个花生组合的166个F1单株进行了真实性鉴定。根据杂种植株含有父母本带型为依据共鉴定出了77个单株为真杂种,真杂种植株数占植株总数的比率为44.86%;收获时根据田间表型鉴定出了79个单株为真杂种,真杂种比率为47.59%。  相似文献   
62.
63.
Greenhouse studies were undertaken to determine the differential Ca absorptive capacity of peanut (Arachis hypogaea L.) fruit of 7 selected cultivars. The cultivars were selected to give a wide range in differential cultivar response to Ca fertilization. Individual fruit were grown in a beaker containing a well stirred and aeriated nutrient solution of 125 ml containing an initial 1.5 mg of Ca. Water was replenished periodically to maintain a total volume of 125 ml. At timely intervals 1 ml aliquots were removed from each beaker and analyzed for Ca. The lowest Ca concentration to which the peanut fruit reduced the Ca concentration in the solution was taken as the Ca absorption efficiency. No difference was found among genotypes for Ca absorption efficiency suggesting other mechanisms of Ca nutrition or plant utilization as the important factors in the Ca nutrition of peanut fruit.  相似文献   
64.
Field screening of 83 groundnut cultivars was undertaken for two seasons to assess their tolerance of salinity based on plant mortality and yield attributes. During the dry season, soil salinity of 4 dS m?1 at sowing and 6–7 dS m?1 21–98 days after sowing (DAS) caused high mortality without seed formation in any cultivars, however, at salinity 4.5 dS m?1 during sowing and 3.5–3.0 dS m?1 15–80 DAS during wet season, 61 cultivars produced seed. The cultivars ‘VRI 3’, ‘UF 70–103’, ‘TKG 19A’, ‘S 206’, ‘Tirupati 4’, ‘M 522’, ‘Punjab 1’, ‘BG 3’, ‘Somnath’ and ‘ICGV 86590’, with high plant stand during both the seasons and over 75 g m?2 seed yield during wet season, were identified salinity tolerant. However, 15 cultivars with more than 50 g m?2 seed yield were moderately tolerant and 28 cultivars with less than 25 g m?2 seed yield were sensitive to salinity.  相似文献   
65.
采用聚丙烯酰胺凝胶电泳的方法,对花生属植物10个栽培种和10个野生种的酯酶同工酶谱带进行测定分析。根据酶谱的差异,栽培种花生与花生区组野生种的平均相似值为12.93%,与其他区组相比其相似值高。表明两者间亲缘关系较近,从生化测定证实了花生区组的野生种是栽培种的近缘祖先的推断。另外,结果表明不同类型的栽培种与花生区组的各个野生种的亲缘关系也存在差异,其中以珍珠豆型品种与A.durenesis的关系最近。  相似文献   
66.
Field studies were conducted to assess boron (B) requirement, critical concentrations in diagnostic parts based on yield response curves and genotypic variation by growing three peanut (Arachis hypogaea L.) cultivars (‘Golden’, ‘BARD-479’, ‘BARI-2000’) on two B-deficient calcareous soils. Boron application significantly increased pod yield of all the cultivars over control. Maximum pod yield increases were: ‘Golden’, 16?23%; ‘BARD-479’, 21?27%; and ‘BARI-2000’, 25?31%. The cultivars varied in B efficiency and cv. ‘Golden’ was the most B efficient (81?86%) while cv. ‘BARI-2000’ was the least efficient (76?80%). Boron requirements for near-maximum (95%) dry pod yield were 0.65 kg ha?1 for ‘Golden’, 0.75 kg ha?1 for BARD-479 and 0.80 kg ha?1 for BARI-2000. Critical B concentrations in shoots and seeds were: ‘Golden’, 33 mg kg?1 and 26 mg kg?1; ‘BARD-479’, 38 mg kg?1 and 31 mg kg?1; and ‘BARI-2000’, 42 mg kg?1 and 33 mg kg?1.  相似文献   
67.
Fourteen wild species of different sections in the genus Arachis and 24 accessions of the AABB allotetraploid A. hypogaea (cultivated peanut) from several countries which belong to different botanical varieties, were analyzed by SSR and AFLP marker systems. The assay-units per system needed to distinguish among all the tested accessions were at least five for SSR or two for AFLP. The genetic distance detected by the SSR markers ranged from 0.09 to 0.95, and the mean was 0.73; and the genetic distance detected by the AFLP markers ranged from 0.01 to 0.79 with an average of 0.42. All the tested peanut SSR primer pairs were multilocus ones, and the amplified fragments per SSR marker in each peanut genome ranged from 2 to 15 with the mean of 4.77. The peanut cultivars were closely related to each other, and shared a large numbers of SSR and AFLP fragments. In contrast, the species in the genus Arachis shared few fragments. The results indicated that the cultivated peanut (A. hypogaea L.) varieties could be partitioned into two main groups and four subgroups at the molecular level, and that A. duranensis is one of the wild ancestors of A. hypogaea. The lowest genetic variation was detected between A. cardenasii and A. batizocoi, and the highest was detected between A. pintoi and the species in the section Arachis. The relationships among the botanical varieties in the cultivated peanut (A. hypogaea L.) and among wild species accessions in section Arachis and those in other sections in the genus Arachis were discussed.  相似文献   
68.
以远杂9102×中花5号杂交后代衍生的重组近交系F8代家系为材料,在含油量测试的基础上,选用10份低油材料(平均含油量52.91%)、12份高油材料(平均含油量58.85%)以及亲本进行SSR引物筛选,通过631对SSR引物扩增,筛选出来源于7对引物的13个有显著差异的片段可以有效区分低油材料和高油材料。以这7对差异引物在F8 RIL群体中扩增,对20份低油家系材料(含油量<55%)和45份高油家系材料(含油量>56%)进行统计分析,获得1个与花生含油量相关的分子标记2A5-250/240,其中,标记2A5-250为低油材料(含油量<55%)所拥有,相符率为95.0%,标记2A5-240为高油材料(含油量>56%)所拥有,相符率为88.9%。用SSR标记2A5-250/240检测11份高油(平均含油量为55.93%)栽培种花生和11份低油(平均含油量为48.41%)栽培种花生,结果表明,标记2A5-240与高油栽培种花生的符合率为63.6%,2A5-250与低油栽培种花生的符合率为90.9%。在19份高油(平均含油量为58.60%)野生花生中,10份野生花生能检测到标记2A5-240。综合分析RIL群体和自然群体的研究结果表明,标记2A5-250/240可用于花生含油量分子标记辅助选择。  相似文献   
69.
花生不同叶位叶片衰老差异的研究   总被引:10,自引:0,他引:10  
在大田条件下,研究了高产花生品种鲁花11号和辐8707主茎不同叶位叶片衰老的差异。结果表明:花生主茎展开18片叶(饱果期)时,主茎叶片叶绿素含量、净光合速率(Pn)、可溶性蛋白质含量(Pr)、超氧化物歧化酶(POD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性逐渐升高,顶3-6叶达最大值,向下逐渐降低。叶片丙二醛(MDA)含量、活性氧(O2^-)释放速率随叶位的降低逐渐升高,顶6叶后开始迅速升高。花生主茎顶1-3叶属快速生长叶,顶4-6(7)叶属缓慢衰老叶,顶7(8)-10叶属迅速衰老叶。两品种间差异不大,辐8707叶片的衰老稍早于鲁花11号。  相似文献   
70.
选取晋西黄土区具有典型代表性的幼龄苹果(Malus pumila)+花生(Arachis hypogaea)间作地作为研究对象,在花生生长季的不同时间对苹果+花生间作地和对照花生单作地的土壤水分进行定位监测,研究苹果+花生间作系统间作界面上土壤水分的时空分布特征和水分效应,及其对花生生长状况和产量的影响。结果表明:1)间作地土壤平均水分含量生长季逐月变化显著,水分耗用最大的时间为7月;2)在垂直方向上,土壤含水量随着土壤深度的增加而增加,在水平方向上,土壤含水量最低值出现在距离果树行最近的区域,并随着与树行距离的增加而增加;3)间作地种间土壤水分耗用量最大的区域为靠近苹果树的表层土壤;4)在当前树龄下,苹果+花生间作系统相对于花生单作土壤水分在整体上表现为负效应,对花生的产量产生了不利的影响,并限制了果农间作系统生态效益和经济效益的进一步提高。建议采取适当的调控和管理措施缓解种间水分竞争并提高花生的产量。  相似文献   
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