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排序方式: 共有380条查询结果,搜索用时 15 毫秒
1.
利用外源DNA导入技术培育向日葵育种新材料   总被引:8,自引:1,他引:8  
采用氯仿-异戊醇-RNA酶法,从菊芋、罗马尼亚向日葵幼叶中提取总DNA,利用花粉管通道法和子房注射法导入向日葵品种“吉农92-1”、“吉农92-5”中,发现D1代及D2代在植株形态、种皮色、百粒重、好粒大小等性状上出现了新的变异类型。  相似文献   
2.
通过对徐州市林场侧柏人工纯林林下植被进行抽样调查,选取形成林火地面易燃物的主要杂草一年蓬、野燕麦为研究对象,用农达(草甘膦异丙胺盐41%水剂)、MCPA(2甲4氯钠盐13%水剂)、精禾草克(精喹禾灵5%乳油)3种防除效率较高的除草剂进行试验。结果表明,农达和MCPA不同浓度混合溶液具很好的防除效果。从生态环境、防除效果和经济成本等因素综合考虑,200倍农达稀释液与200倍MPCA稀释液的混合液对一年蓬和野燕麦防除效果最佳,可应用在森林防火隔离带的建设中。  相似文献   
3.
Rust resistance in the sunflower line P386 is controlled by Pu6, a gene which was reported to segregate independently from other rust resistant genes, such as R4. The objectives of this work were to map Pu6, to provide and validate molecular tools for its identification, and to determine the linkage relationship of Pu6 and R4. Genetic mapping of Pu6 with six markers covered 24.8 cM of genetic distance on the lower end of linkage Group 13 of the sunflower consensus map. The marker most closely linked to Pu6 was ORS316 at 2.5 cM in the distal position. ORS316 presented five alleles when was assayed with a representative set of resistant and susceptible lines. Allelism test between Pu6 and R4 indicated that both genes are linked at a genetic distance of 6.25 cM. This is the first confirmation based on an allelism test that at least two members of the Radv/R4/R11/ R13a/R13b/Pu6 cluster of genes are at different loci. A fine elucidation of the architecture of this complex locus will allow designing and constructing completely new genomic regions combining genes from different resistant sources and the elimination of the linkage drag around each resistant gene.  相似文献   
4.
J. Domínguez 《Plant Breeding》1996,115(3):203-204
The inheritance of resistance to a highly virulent population of sunflower broomrape (Orobanche cernua) has been studied in R-41, a Spanish sunflower restorer inbred line. Using the cytoplasmic male-sterile inbred line HA-89 (cms; very susceptible to this population of broomrape) as a female parent, progenies of the cross with R-41, i.e. Fl, F2 and BC1 to both parents, as well as the parental lines, were analysed for their reaction to the broomrape population EC-94. The goodness of fit of the observed vs expected segregation ratios indicated that the inheritance of resistance to broomrape in line R-41 is conferred by two independent dominant genes.  相似文献   
5.
王改改  周军  宋云 《农学学报》2021,11(9):64-67
筛选出适宜延安种植的菊芋品种,解决延安菊芋品种单一的问题,促进延安菊芋产业化发展。对引进的6个菊芋品种和1个当地品种进行田间比较试验,调查各品种田间的生育期、农艺性状和经济性状。试验结果表明,‘廊芋1号’和‘廊芋2号’2个品种的综合性状表现较好,其产量分别为57378.68、56228.10 kg/hm2,较对照增产分别为5.11%、3.00%。其余品种表现一般,产量均低于对照品种,需继续试种观察。 ‘廊芋1号’和‘廊芋2号’较适合在延安种植,可进行示范推广。  相似文献   
6.
羟基肉桂酰辅酶A:莽草酸/奎宁酸羟基肉桂酰转移酶(HCT)是木质素合成过程中的关键酶之一。本研究构建了菊芋HtHCT基因的植物表达载体pCAMBIA1390-HtHCT,分别对拟南芥和本氏烟进行遗传转化,并对转基因植株进行生理生化指标测定。PCR和RT-PCR结果表明,HtHCT基因已经插入到受体植物基因组中,并能进行转录;转基因植株生理生化指标检测表明,HtHCT基因能够调节拟南芥和本氏烟中木质素的含量及组成,并对受体材料的类黄酮合成亦有一定的影响。  相似文献   
7.
利用菊芋地下块茎作外植体,在附加1.2mg·L~(-1)2,4-D 的 MS 培养基上诱导愈伤组织形成,经同样 MS 液体培养基培养形成悬浮系;菊芋悬浮细胞转入含5.0mg·L~(-1)的6-BAP、1.0mg·L~(-1)2,4-D 的 MS 液体培养基内.经9d 培养可使约30%~50%悬浮细胞转化为具次生壁条纹的导管分子。  相似文献   
8.
向日葵品种抗向日葵螟鉴定及抗性评价方法   总被引:1,自引:0,他引:1  
利用田间自然抗虫鉴定法连续3年在内蒙古巴彦淖尔市对56个向日葵品种进行了抗向日葵螟鉴定,结果表明,17个油葵品种中除P50表现为中抗(籽粒被害率为6.7%),其余品种全部表现为高抗,籽粒被害率均在0~2.5%;而39个食葵品种中仅新食葵7号表现为高抗(籽粒被害率为1.9%),其余多表现为感虫或高感,籽粒被害率在5.8%~54.1%。进一步利用黑色素鉴定法对所有品种进行了室内检测,其结果与田间抗虫鉴定结果基本吻合。由此认为:在进行田间自然抗虫鉴定时,宜根据田间向日葵螟成虫种群动态选择适宜的播期,使向日葵的开花期与向日葵螟成虫发生盛期尽量吻合,以提高害虫对向日葵的选择压力和鉴定结果的科学性,同时避免出现播期避害现象,干扰鉴定结果的准确性。  相似文献   
9.
Chlorosis level is a useful parameter to assess imidazolinone resistance in sunflower (Helianthus annuus L.). The aim of this study was to quantify chlorosis through two different methods in sunflower plantlets treated with imazapyr. The genotypes used in this study were two inbred lines reported to be different in their resistance to imidazolinones. Chlorosis was evaluated by spectrophotometrical quantification of photosynthetic leaf pigments and by a bioinformatics-based color analysis. A protocol for pigment extraction was presented which improved pigment stability. Chlorophyll amount decreased significantly when both genotypes were treated with 10 μM of imazapyr. Leaf color was characterized using Tomato Analyzer® color test software. A significant positive correlation between color reduction and chlorophyll concentration was found. It suggests that leaf color measurement could be an accurate method to estimate chlorosis and infer chlorophyll levels in sunflower plants. These results highlight a strong relationship between imidazolinone-induced chlorosis and variations in leaf color and in chlorophyll concentration. Both methods are quantitative, rapid, simple, and reproducible. Thus, they could be useful tools for phenotyping and screening large number of plants when breeding for imidazolinone resistance in this species.  相似文献   
10.
S. Barotti    M. Fambrini    C. Pugliesi  A. Lenzi 《Plant Breeding》1995,114(3):275-276
In vitro regenerated sunflower (Helianthus annuus L.) plants (R1) were self-fertilized and the R2 generation was evaluated for qualitative traits. A broad range of phenotypic variation was observed and mutation frequencies were calculated. Some in vitro induced variant phenotypes were similar to known spontaneous or induced mutations in sunflower, while others were new. Chlorophyll and carotenoid deficiencies, chimaerical variegation, fasciated stem and capitulum, abnormal shoot development, and other morphological variations, were noted. Substitution of anthers with petaloid structures in a disk-floret mutant indicates a possible homeotic mutation induced by in vitro tissue culture.  相似文献   
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