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81.
82.
孝顺竹种胚愈伤组织悬浮培养条件优化 总被引:4,自引:2,他引:4
本研究利用孝顺竹种胚诱导出的淡黄色胚性愈伤组织为材料,对影响细胞悬浮培养的摇床转速、培养液2,4-D浓度、继代天数、接种细胞浓度(W/V)等因素进行了研究.结果表明,悬浮培养时的摇床转速以120 r/min时培养效果较好,转速低于100 r/min时,愈伤组织容易结团,分散性差;适宜的2,4-D浓度为4~6 mg/L,低于4 mg/L时愈伤组织易褐变;接种后培养7 d是最佳的转接时期,至多不能超过10 d;接种细胞密度以4.0%最为合适,可保持较高的增殖速度,同时培养产物较多.在50 mL培养液(NB+500 mg/L Pro-line+500 mg/L Glutamine+300 mg/L Hydrolyzed casein+30 mg/L Sucrose+4~6 mg/L 2,4-D)中接种4.0%的愈伤组织,于120 r/min的转速下经过7 d培养,可增殖一倍以上,以后每7 d继代转接一次,培养大约一个月,便可以建立生长迅速、分散性好、均一的悬浮细胞系. 相似文献
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84.
Transgene expression was evaluated for Gladiolus plants transformed with either the CaMV 35S, double CaMV 35S, rolD, or Arabidopsis UBQ3 promoter controlling the uidA or bean yellow mosaic virus coat protein gene in either the sense or antisense orientation to determine differences in expression for plants grown in the greenhouse and outdoors for two years. There was more variability in GUS expression when plants were grown outdoors than in the greenhouse for two years. Four of the six transformed plant lines with the UBQ3, rolD, and CaMV 35S promoters grown outdoors showed significant differences in GUS expression from year to year as compared to two of the six lines with the UBQ3 and rolD promoters grown in the greenhouse. When grown the same year, two plant lines with the CaMV 35S and one line with the rolD promoter showed 2–16× higher levels of GUS expression outdoors than in the greenhouse, and one plant line with the UBQ3 promoter had 31× higher GUS expression in the greenhouse instead of outdoors. Three of six plant lines transformed with the bean yellow mosaic virus coat protein gene in either the sense or antisense orientation under control of the double CaMV 35S promoter showed obvious transgene expression as compared to three lines that did not show expression or negligible expression for both years when plants were grown both outdoors and in the greenhouse. This study verified long-term gene expression, rather than silencing, for Gladiolus plants when grown outdoors and in the greenhouse from year to year. 相似文献
85.
以雅安扁穗牛鞭草的幼穗为外植体,研究了2,4-D浓度和不同取材部位对愈伤组织诱导的影响以及继代培养时不同浓度的2,4-D对愈伤组织增殖、分化、生根的影响.结果表明:以幼穗下部为外植体接种在MS+2,4-D 7.0 mg/L培养基中,颗粒状愈伤组织的诱导率高达100.00%;MS+2,4-D 1.0 mg/L是幼穗愈伤组织较为适宜的继代增殖培养基,在该培养基上颗粒状胚性愈伤组织的出愈率为89.44%,愈伤组织的绿苗分化率和生根率都可达100%,平均绿芽点数和生根数等均极显著高于其他处理. 相似文献
86.
选用3份水稻多胚材料(PM13,PJ-1和PM14)进行2,4-D,6-BA浸种和喷穗试验.结果表明,用这两种植物佳长调节物质浸种和喷穗对水稻多胚苗频率有不同程度的影响:a.以5ppm2,4-D和10ppm,20ppm6-BA浸种的提高了多胚苗频率,但对不同材料(基因型)的影响程度有差异;b.用5ppm6-BA和5ppm2,4-D+20ppm6-BA,20ppm2,4-D+20ppm6-BA,10ppm2,4-D+20ppm6-BA喷穗效果好,提高程度均达到极显着水准,此外,5ppm-BA和5ppm2,4-D+20ppm6-BA处理的不定胚频率提高也达极显着水准.植物生长调节物质喷穗还诱导出孤雌生殖,证实了多胚现象与无融合生殖之间有显着的相关. 相似文献
87.
小麦喷施2,4—D丁酯和复硝钠合剂的除草增产效应 总被引:1,自引:0,他引:1
经连续三年的小区试和生产实验表明,小麦在一定生长发育时期,适时、适量、均匀一致地喷施2,4-D丁酯和复硝钠合剂(简称合剂)不仅除草率可达85%以上,而且有效地加速小穗小花分化促进了小麦双重小穗和顶端小穗的分枝,使穗粒数明显增加,茎杆显著降低.从而为小麦生产开辟了一条新的化学调控增产途径. 相似文献
88.
于11月中旬,用200 ppm 2,4-D和150 ppm多菌灵处理果实,挂树保鲜120 d后,稳果率达100%,好果率达99%,果实平均增重4.63%,可溶性糖含量提高2.4%,净增利润1600元/t,但次年减产5.8% 相似文献
89.
Wolfgang Henninger DR MED VET E. Mairi Frame BVMS DVR MRCVS Michael Willmann DR MED VET Hubert Simhofer DR MET VET Dieter Malleczek MAG MED VET Sibylle M. Kneissl DR MED VET Elisabeth Mayrhofer PROF DR MED VET 《Veterinary radiology & ultrasound》2003,44(3):269-276
Sinusitis is a common disorder in horses and may result from trauma, dental diseases, or space-occupying lesions. Radiography can only provide a limited amount of information. Computed tomography (CT) has been documented as an alternative imaging method. Eighteen horses (mostly Warmblood) with signs of chronic sinusitis were examined preoperatively with CT to assist in diagnosis of the underlying cause. There was a group of common CT features in horses with dental disease and sinusitis. The first molar was the most frequently affected maxillary cheek tooth. Hypoattenuation of the cementum, destruction of the enamel, and filling of the infundibular cavity with gas were the most frequent CT findings associated with caries. Gas bubbles within the bulging root area or fragmentation of the root in combination with swelling of the adjacent sinus lining were the most important CT features of dental decay. CT findings associated with sinusitis included excessive thickening of the respiratory epithelium in the rostral maxillary sinus; the caudal maxillary sinus was less often involved. The infraorbital canal, the nasomaxillary duct, and the frontomaxillary aperture were usually involved. The maxillary bone, however, especially the facial crest, was involved in nearly every horse, being characterized by endosteal sclerosis, thickening, periosteal reaction, and deformation leading to facial swelling in chronic infections. CT images allowed identification of involvement of individual teeth more clearly to reveal the diseased one for treatment. Three-dimensional imaging allowed improved understanding of the extent and severity of the pathologic change. 相似文献
90.
Junqiang Li Yongqing Wang Lihua Lin Lijun Zhou Nan Luo Qunxian Deng Junren Xian Chunxia Hou Yuan Qiu 《Scientia Horticulturae》2008
The object of this study was to induce embryogenesis and establish plant regeneration system for anther culture in loquat (Eriobotrya japonica L.). Cold pretreatment was a key factor, and supplement of 2,4-D in the media was absolutely necessary for induction of calluses from cultured loquat anthers. The best response of anthers to in vitro culture was obtained when a 48-h cold pretreatment was employed to flower buds at 4 °C in darkness. Genotype was a decisive factor for embryo differentiation. When anther-derived calluses of three loquat cultivars, i.e., cv. ‘Longquan1’, ‘Dawuxing’ and ‘Zaozhong6’, were transferred to embryo differentiation medium, embryos were induced only for cv. ‘Dawuxing’ on MS medium containing 3% sucrose, 0.23 μM ZT in combination with 0.05 μM NAA + 0.05 μM IBA or 0.11 μM NAA + 0.10 μM IBA, and the differentiation rates were 3.33% and 10.00%, respectively. The results of histological studies showed that embryos developed through typical globular, heart, torpedo and cotyledon stages after 4 weeks of culture. The treatment designed to mature the embryos on medium containing 3% of sucrose at 4 °C under darkness for 4 weeks was effective for subsequent embryo germination and plant conversion, which gave rise to 72.5% plant recovery. Cytological studies showed that 26 plantlets were haploids (n = 17) and the remaining 4 plantlets were diploids for the 30 regenerants tested. 相似文献