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Field evaluation of antisense RNA mediated inhibition of GBSS gene expression in potato 总被引:2,自引:0,他引:2
G. J. Kuipers J. T. M. Vreem H. Meyer E. Jacobsen W. J. Feenstra R. G. F. Visser 《Euphytica》1991,59(1):83-91
Summary Granule-bound starch synthase (GBSS) catalyses the synthesis of amylose in starch granules. Analysis of antisense RNA mediated inhibition of GBSS gene expression in large numbers of tubers from in vitro grown, greenhouse grown and field grown transgenic potato plants revealed stable and total inhibition of GBSS gene expression in one clone. In three other transgenic genotypes partial and unstable inhibition was found. In these genotypes both GBSS activity and amylose content were remarkably reduced compared with the non-transformed control genotype. No relationship was found between the level of inhibition of GBSS gene expression and yield and dry matter content. 相似文献
74.
Factors influencing tissue culture responses of mature seeds and immature embryos in turf-type tall fescue 总被引:23,自引:0,他引:23
In an effort to optimize tissue culture responses of turf‐type tall fescue for genetic transformation, the effects of five culture medium supplements on tissue culture responses were investigated with immature embryos and mature seeds of an elite cultivar, ‘Coronado’, as explant tissues. For both explants, calli induced on 6‐benzylaminopurine (BAP)‐containing medium had significantly improved regeneration ability. The optimal concentration of BAP for the induction of regenerable callus from mature seeds was 0.1 mg/l. Thidiazuron also improved callus regeneration frequency of mature seeds. Casein hydrolysate, L‐proline and myo‐inositol improved callus induction of immature embryos but not mature seeds. They did not improve callus regeneration frequencies with either explant tissue. By simply slicing the mature seeds into two halves longitudinally, the callus induction frequencies, as well as the corresponding overall plant regeneration frequencies, were increased approximately three‐ to six‐fold in all three combinations of 2,4‐dichlorophenoxyacetic acid and BAP in callus induction media. 相似文献
75.
环境胁迫和激素诱导甘蔗ACC合成酶基因家族三个成员的表达 总被引:1,自引:2,他引:1
ACC合成酶(ACS)是高等植物乙烯生物合成途径中的限速酶。在克隆到甘蔗ACC合成酶基因家族3个成员Sc-ACS1、Sc-ACS2和Sc-ACS3的基础上,分别以它们作为探针,检测了激素诱导和环境胁迫对甘蔗苗期该3成员表达的影响。结果表明,乙烯利诱导Sc-ACS1在叶中表达,在根中不表达;Sc-ACS2在根、叶中表达;Sc-ACS3主要在根部表达,在叶中不表达。在甘蔗叶片中,Sc-ACS1对冷胁迫、暗培养和LiCl胁迫均有应答,并受植物生长激素IAA诱导而表达;Sc-ACS2无论是在生长激素诱导还是环境胁迫下,其mRNA均维持较低水平。 相似文献
76.
复硝酚钠和DA-6对生姜生长及产量品质的影响 总被引:3,自引:0,他引:3
在大田栽培条件下,研究了新型植物生长调节剂复硝酚钠、DA-6对生姜生长、产量及品质的影响。结果表明,复硝酚钠、DA-6均可显著促进生姜的生长,但生长前期以促进根系生长的效果最为显著|随着生长的进行,生姜植株各器官鲜质量亦显著高于对照。生姜收获时,复硝酚钠、DA-6处理的生姜株高分别比对照增加11.59%和14.02%,分枝数分别增加24.59%和28.69%,产量分别提高18.53%和22.30%,但复硝酚钠、DA-6处理间差异不显著。此外,复硝酚钠、DA-6还不同程度地提高了生姜根茎淀粉、可溶性蛋白及氨基酸含量。 相似文献
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78.
金冠六号是以06-441为母本,06-504为父本育成的早熟番茄新品种.无限生长型,生育期110天左右,平均单果质量200 g左右,可溶性固形物含量4.5%左右.果实扁圆形,粉红色,酸甜适口,果实硬度高,耐贮运,商品性好.抗病毒病和叶霉病,耐低温弱光能力强,适于保护地栽培. 相似文献
79.
Wei Yao Hongliang Zhao Jie Li Zhijun Wang Yuhuang Han Shuren Dong Yuejiang Wang Fenglai Wang 《畜牧与生物技术杂志(英文版)》2011,2(3):141-152
This experiment was conducted to investigate the effects of different ratios of n-6:n-3 polyunsaturated fatty acids (PUFA) in sow diets on the performance of lactating sows and their piglets at low digestible energy intakes.Twenty-one pregnant Landrace sows were assigned to one of three diets from day 108 of gestation until weaning (26 to 29 d),containing n-6∶n-3 PUFA ratios of 3∶1,8∶1 and 11∶1.The effects on sow and litter production traits and on sow body condition were examined.There were no differences among treatments in daily feed intakes or in changes in sow weight and back-fat levels during lactation.Litter size,litter weight at birth and weaning and litter average daily weight gain were also unaffected by treatment.As expected,large differences were observed in n-6 and n-3 fatty acids in the colostrum and plasma of sows and piglets (P < 0.01 ).The ratio of n-6∶n-3 PUFA the diet was positively correlated with those in colostrum,sow plasma and piglet plasma ( R2 =0.55,0.80 and 0.80,respectively).Sow plasma insulin and IGF-I levels at weaning were unaffected by the treatments.Plasma leptin ( P < 0.05) concentrations were increased in sows fed the diet with a n-6∶ n-3 ratio of 8∶1.Immunoglobulin concentrations in colostrum were not altered by dietary treatment.Plasma IgG concentrations at d 14 were highest in piglets from sows fed the 8∶1 ratio of n-6∶n-3.Furthermore,this group had the highest IgA concentrations at day 21 of lactation compared with the other two groups ( P < 0.05 ).In summary,our study demonstrated that at low digestible energy levels,altering the ratio of n-6∶n-3 PUFA in the diets for lactating sows affected immune components and the fatty acid composition of lactating sows and their piglets.Further studies are needed to examine whether higher levels of fat supplementation than those used in the present study ( 1.5% ) can successfully enhance performance. 相似文献
80.
XiaohuiRen Zhunli Qi Xiuwen Zhang Jianwei Dai Linlin Hao SongcaiLiu Yongliang Zhang 《畜牧与生物技术杂志(英文版)》2011,2(3):173-178
Both growth hormone-releasing peptide 6 (GHRP-6) and growth hormone-releasing hormone (GHRH) have potent GH-releasing activity in animals.We have previously demonstrated that the administration of a plasmid encoding the GHRH gene to pregnant mice and pig augmented long-term growth in first generation progeny,and that the administration of GHRP-6 results in growth augmentation in mice and rabbits.However,it has not yet been reported if GHRP-6 induces intergenerational growth effects in pigs.Ploy lactic-co-glycolic acid (PLGA) microsphere adsorption of treatment proteins enhances gene expression,genetic immunization and the ability to protect plasmid DNA and peptides from degradation.The current study was conducted to determine the growth performance of piglets born to gilts treated with GHRP-6 incorporated into thermosensitive PLGA-PEG-PLGA triblock copolymers.Gilts were injected intra-muscularly once at day 85 of gestation with 30 mg of GHRP-6-loaded thermosensitive PLGA-PEG-PLGA triblock copolymers.Piglets were weighed periodically between birth and 28 days.Mean body weights of piglets born to GHRP-6-treated gilts were 6.58% to 18.89% (P < 0.05 ) greater than those of piglets born to control gilts.This study confirms that enhanced maternal GHRP-6 mediated by thermosensitive PLGA-PEG-PLGA can augment growth of piglets. 相似文献