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131.
Genetic transformation of embryogenic suspension cultures of sweetpotato cv. Lizixiang wasconducted by using Agrobacterium tumefaciens strain A208SE harboring the binary vectors pROA93 with β-glucronidase (GUS) and neomycin phosphotransferase (NPT Ⅱ ) genes. The results indicated that embryogenicsuspension cultures precultured for 1 -3 d were suitable for the transformation. The optimal cocultivation timewas 4 - 5 d. The optimal concentration of kanamycin was 50-75 mg L-1 for suspension culture and 100 mg L-1for embryogenic callus proliferation and plant regeneration. The optimal concentration of carbencillin was 100mg L-1. Transgenic plants identified with GUS assays and PCR analyses were obtained. 相似文献
132.
以吸水链霉菌NND 5 2菌株为原始菌株 ,利用紫外诱变和LiCl复合处理 ,采用琼脂柱移菌法进行初筛。用清酒酵母作为特异性指示菌 ,经复筛获得一株除莠霉素A高产菌株 ,产量为 980 0 9μg·mL-1 ,比原始菌株提高了 2 2 6倍。 相似文献
133.
甘薯胚性悬浮细胞遗传转化的研究 总被引:16,自引:0,他引:16
以甘薯品种栗子香的胚性悬浮细胞为材料 ,以A2 0 8SE(pROA93)为供体菌株 ,对甘薯胚性悬浮细胞遗传转化的基本条件进行了研究。结果表明 ,对胚性悬浮细胞预培养 1~ 3d有利于转化 ,适宜的共培养时间为 4~ 5d ,适宜的Kan浓度为 5 0~ 75mg·L-1(悬浮培养阶段 )和 10 0mg·L-1(增殖培养阶段和植株再生阶段 ) ,适宜的Carb浓度为 10 0mg·L-1。获得了经GUS检测及PCR检测的转基因植株。 相似文献
134.
沾河林区夏季森林鸟类群落结构研究 总被引:4,自引:0,他引:4
1990年5—6月在黑龙江省沾河林业局,通过路线调查法研究了该地区夏季森林鸟类群落的结构,旨在揭示鸟类群落的物种多样性在空间上的变化模式以及它与物种生态位的关系。研究结果表明,该地区不同鸟类群落的物种多样性的排列顺序为针阔混交林>阔叶林>灌丛>针叶林。鸟类群落的物种多样性存在着垂直变化。也随栖位而改变,并且这些变化在各鸟类群落中表现出不同的模式,在不同的鸟类群落中,5种常见鸟类(灰头鹀、大山雀、沼泽山雀、黄腰柳莺、黑眉苇莺)有不同的生态位宽度和生态位重叠。鸟类群落的物种多样性与群落中各物种生态位的平均宽度和重叠存在一定的相关关系。 相似文献
135.
楸树扦插繁殖技术研究 总被引:7,自引:0,他引:7
对揪树进行一系列扦插试验,结果表明:硬杆扦插成活率86.0%;嫩枝82.9%;半硬枝76.7%。通过正交试验,筛选出三套扦插因素与水平的较佳组合:1)硬枝扦插,1月10日扦插采用NAA(奈乙酸)100×10^-6浸24h使用基部条;2)硬枝扦插,用16℃的水浸15d,然后再用0.3%KMnO4浸30min;3)半硬枝扦插,NAA100×10^-6处理60min后插于细沙基质中。嫩枝扦插亦找到了适宜 相似文献
136.
2008年1月上旬至2009年7月下旬,对非洲引进的3个桃花心木种源的幼树进行每周1次的观测.结果显示:种源间抗寒能力、树高生长和地径生长以及速生期都存在明显差异.种源3-1324与4-1325在苗期表现出一定的抗寒性,种源1-1320苗期对低温敏感.总体上,非洲桃花心木幼树1年抽梢4~7次,1~2月为树高生长休眠期,... 相似文献
137.
以含有RD29A目的基因和NPTⅡ筛选基因的根癌农杆菌菌株LBA4404、GV3101和EHA105侵染饲用型四倍体刺槐(Robinia pseudoacacia)、国槐(Sophora japonica L.)和红叶石楠(Davidson Photinia)的组培苗叶片,研究3个树种对根癌农杆菌菌株和不同抗生素(替门汀和头孢霉素)的敏感性、以及根癌农杆菌菌株对3个树种的侵染能力。结果表明,不同树种、不同根癌农杆菌株和不同抗生素种类均对转化效果产生明显影响,红叶石楠是最佳受体材料,3个菌株侵染后的平均抗性愈伤率为37.0%,其次为国槐,四倍体刺槐最低;根癌农杆菌菌株LBA4404侵染能力最强,3个树种的平均抗性愈伤率达到33.3%、平均分化率达到17.6%;替门汀对农杆菌侵染后的红叶石楠组培叶片抑菌效果最好。 相似文献
138.
Rajat Goswami Rajkumar Uttamrao Zunjare Suphiya Khan Aanchal Baveja Vignesh Muthusamy Firoz Hossain 《Plant Breeding》2019,138(2):174-183
Vitamin A deficiency in humans is a widespread health problem. Quality protein maize (QPM) is a popular food rich in lysine and tryptophan, but poor in provitamin A (proA). Here, we report the improvement of an elite QPM inbred, HKI1128Q for proA using marker‐assisted introgression of crtRB1‐favourable allele. HKI1128 was one of the parental lines of three popular hybrids in India and was converted to QPM in our earlier programme. Severe segregation distortion for crtRB1 was observed in BC1F1, BC2F1 and BC2F2. Background selection by 100 SSRs revealed mean recovery of 91.07% recurrent parent genome varying from 88.78% to 93.88%. Across years, introgressed progenies possessed higher mean β‐carotene (BC: 9.22 µg/g), β‐cryptoxanthin (BCX: 3.05 µg/g) and provitamin A (proA: 10.75 µg/g) compared to HKI1128Q (BC: 2.26 µg/g, BCX: 2.26 µg/g and proA: 3.38 µg/g). High concentration of essential amino acids, viz. lysine (mean: 0.303%) and tryptophan (0.080%) in endosperm, was also retained. Multi‐year evaluation showed that introgressed progenies possessed similar grain yield (1,759–1,879 kg/ha) with HKI1128Q (1,778 kg/ha). Introgressed progenies with higher lysine, tryptophan and proA hold immense potential as donors and parents in developing biofortified hybrids. 相似文献
139.
Pankaj Sharma Inderjit Singh Asmita Sirari Gaurav Khosla Gurjeet Singh Navkiran Kaur Ludhar Sarvjeet Singh 《Plant Breeding》2019,138(6):741-747
Inheritance of fertility restorer gene in pigeonpea was studied using F2 and BC1F1 populations derived from cross AL103A × IC245273. It was found to be controlled by single dominant gene. Out of 228 SSR primer pairs, 33 primer pairs showed parental polymorphism, while four primers were found polymorphic in bulk segregant analysis (BSA). These four primers viz., CcM 1615, CcM 0710, CcM 0765 and CcM 1522 were used for genotyping of F2 population and were found to be placed at 3.1, 5.1, 28.1 and 45.8 cM, respectively. Two of them, CcM 1615 and CcM 0710, evinced clear and unambiguous bands for fertility restoration in F2 population. The Rf gene was mapped on linkage group 6 between the SSR markers CcM 1615 and CcM 0710 with the distances of 3.1 and 5.1 cM, respectively. The accuracy of the CcM 1615 was validated in 18 restorers and six maintainer lines. The marker CcM 1615 amplified in majority of male restorer lines with a selection accuracy of 91.66%. 相似文献
140.
AIM: To explore the effect of tanshinone ⅡA on human osteosarcoma HOS cells and the underlying mechanism.METHODS: The cell viability and the appropriate dose of tanshinone ⅡA were determined by CCK-8 assay. Colony formation assay and Transwell assay were used to investigate the proliferation and migration abilities of the HOS cells treated with tanshinone ⅡA. The apoptosis of the HOS cells was monitored by Hoechst 33258 staining, transmission electron microscopy and flow cytometry. The protein levels of apoptosis-related molecules and JNK signaling-associated proteins were determined by Western blot. Meanwhile, a JNK inhibitor was added for confirming the relationship between the pathway and apoptosis mentioned above.RESULTS: Tanshinone ⅡA inhibited both HOS cell proliferation and migration in a dose-and time-dependent manner. Exposure of the HOS cells to tanshinone ⅡA resulted in the activation of apoptosis. Tanshinone ⅡA treatment increased the protein levels of cleaved caspase-3, Bax and JNK signaling-associated proteins, and decreased the protein level of Bcl-2, which were reversed by JNK inhibitor SP600125. Moreover, the result of CCK-8 assay revealed that tanshinone ⅡA-induced cell death was alleviated by JNK inhibitor.CONCLUSION: Tanshinone ⅡA induces cell growth inhibition and the activation of apoptosis via JNK signaling pathway in human osteosarcoma HOS cells. 相似文献