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991.
南方籼稻抗旱性状的遗传分析 总被引:2,自引:0,他引:2
在旱地条件下 ,对籼稻 9个抗旱性状进行了遗传分析。结果表明 :( 1 )各抗旱指标都存在遗传变异 ,其中穗茎粗、单株有效穗数、每穗实粒数、剑叶长、叶绿素a/b、脯氨酸含量和自由水含量的遗传变异主要受加性效应的影响 ,倒二节间长和谷粒宽的遗传变异主要受显性效应的影响 ;所有抗旱指标都存在显性×环境的互作效应 ,每穗实粒数、叶绿素a/b和自由水含量还存在加性×环境的互作效应。 ( 2 )各抗旱指标都存在普通狭义遗传率 ;每穗实粒数、叶绿素a/b和自由水含量还存在互作狭义遗传率 ,且后两者的互作狭义遗传率大于普通狭义遗传率 ,受环境的影响较大。 ( 3 )单株有效穗数、穗茎粗和倒二节间长既存在普通杂种优势 ,又存在互作杂种优势 ,且环境不改变这三项指标显性基因作用的方向 ,其中倒二节间长为负向杂种优势 ;叶绿素a/b和脯氨酸含量只存在负向互作杂种优势 ,其余各指标杂种优势不明显。 ( 4)每穗实粒数、叶绿素a/b和自由水含量的加性×环境互作效应较大 ,另外 6个指标的加性×环境互作效应都为 0。 相似文献
992.
东方百合盆栽新品种‘喜来临’ 总被引:1,自引:0,他引:1
‘喜来临’是以‘元帅’(Acpulco)为母本,‘迈阿密’(Miami)为父本杂交选育出的盆栽东方百合新品种。植株矮小,平均株高52 cm。花朵数量较多,围径12 ~ 14 cm的种球种植后花朵数量3 ~ 4朵,围径16 ~ 18 cm的种球种植后花朵数量5 ~ 8朵。花粉色,花苞大,品质好,花期长。茎杆粗壮,无叶烧,抗性强,易繁殖,种球繁育周期短。 相似文献
993.
SUN Guo-fang DING Hao LI Ju-xiang HONG Kui Dong Jia-long WU Qing-hua CHENG Xiao-shu 《园艺学报》2011,27(12):2307-2312
AIM: To investigate the effects of Rho-associated coiled-coil protein kinase-1 (ROCK1) and ROCK2 on apoptosis induced by hypoxia in rat cardiomyocytes. METHODS: Rat cardiomyocytes were cultured primarily and identified using an antibody targeting α-actin of striated muscle. ROCK1-shRNA and ROCK2-shRNA were transiently transfected into the cells by liposome. After 48 h, these cells were subject to hypoxia for 6 h. The cells were divided into 5 groups: blank control group, hypoxia group, hypoxia+negative control shRNA group, hypoxia+ROCK1-shRNA group and hypoxia+ROCK2-shRNA group. The beating frequency and rhythm of the cardiomyocytes were assessed by microscopy. The activity of lactate dehydrogenase (LDH) in the cell culture supernatants was detected by automatic biochemical analyzer. The cell survival rate was analyzed by the method of MTT. The cell apoptotic rate was assessed by flow cytometry. Western blotting was used to determine the expression of ROCK1, ROCK2, caspase-3 and p-PI3K. RESULTS: The primary culture of the cardiomyocytes was successful. Western blotting results showed that the transfection of ROCK1-shRNA or ROCK2-shRNA decreased the expression of ROCK1 or ROCK2 in the cardiomyocytes. Hypoxia slowed down the beat frequency of the cardiomyocytes, also made the rhythm disorder. Hypoxia increased the release of LDH and decreased the cell survival rate. Flow cytometry results showed that hypoxia increased the cell apoptotic rate. Hypoxia increased the expression of caspase-3 and decreased the expression of p-PI3K. Transfection of ROCK1-shRNA and ROCK2-shRNA into the cardiomyocytes reduced all the effects of hypoxia mentioned above. CONCLUSION: Down-regulation of ROCK1 and ROCK2 expression suppresses the apoptosis of rat cardiomyocytes induced by hypoxia. The mechanism is associated with the inhibition of caspase-3 activation and the up-regulation of p-PI3K expression. 相似文献
994.
同时检测猪圆环病毒2型、猪细小病毒和伪狂犬病毒连接酶检测反应-PCR基因芯片检测方法的建立 总被引:1,自引:0,他引:1
为快速、灵敏、准确地同时检测和鉴别猪圆环病毒2型(PCV2)、猪细小病毒(PPV)和伪狂犬病毒(PRV)的方法,本研究采用连接酶检测反应(LDR)-PCR和基因芯片技术建立一种新型检测方法.首先在3种病毒的保守区内分别设计一对LDR探针,两端各连接一段通用序列,依次进行LDR、通用引物荧光标记扩增和芯片杂交,同时比较引物标记和Cy5 -dCTP标记方法的灵敏度.结果表明该方法可以特异地检测PCV2、PPV和PRV3种病毒,而对牛病毒性腹泻病毒、猪传染性胃肠炎病毒、猪流行性腹泻病毒、猪繁殖与呼吸障碍综合征病毒、猪瘟病毒、乙型脑炎病毒、猪圆环病毒1型检测结果均为阴性;对3种病毒的最低检测限少于10个拷贝;Cy5-dCTP标记检测的灵敏度显著高于引物标记.利用建立的方法对41例临床样品进行检测,与普通PCR检测结果符合率为97.6%~100%.该方法的建立为基础研究和临床应用提供了技术平台. 相似文献
995.
996.
以苹果试管苗叶片的再生不定芽嫩叶为试材,对苹果体细胞悬浮系的建立及植株再生的影响因素进行了研究.结果表明:在MS+NAA 0.5 mg/L+BA 2.0 mg/L培养基上可诱导获得高活力的愈伤组织.将该愈伤组织转入MS+2,4-D 2.0 mg/L+BA 1.0 mg/L液体培养基中培养,采用无菌筛网分离获得含单个细胞和少于8~10个细胞的小细胞团进行继代培养,建立体悬浮细胞培养系.将悬浮细胞转到MS+2,4-D 2.0 mg/L+BA 1.0 mg/L的固体增殖培养基上暗培养25 d后,可形成微型愈伤组织,将该愈伤组织转到MS+BA 5.0 mg/L+IAA 0.5 mg/L的植株再生培养基上暗培养30 d后转入光下,光照培养30 d后53%的愈伤组织可再生植株.该研究建立的苹果体细胞悬浮培养技术,不仅可用于细胞融合及遗传转化过程中杂种细胞和转化细胞的分离及植株再生研究,而且对于利用组织培养技术筛选变异株系也具有重要意义. 相似文献
997.
新疆植物特有种的地理分布规律 总被引:1,自引:0,他引:1
通过对新疆82个区划单位的植物特有种现状进行统计分析,结果表明:新疆植物特有种约271种,隶属38科119属。受气候影响,植物特有种的区域分布水热条件较优越的山地丘陵区显著多于荒漠平原区;天山、阿尔泰山、昆仑山及帕米尔高原的山谷为新疆植物特有种的集中分布区;塔里木盆地及吐鲁番—哈密盆地平原区因自然环境条件严酷,特有种分... 相似文献
998.
QuanLin MA Fang CHENG YouJun LIU FangLin Wang DeKuai ZHANG HuJia JIN Gansu Key Laboratory of Desertification Combating & Minqin National Studies Station for Desert Steppe Ecosystem Gansu Desert Control Research Institute Lanzhou China 《干旱区科学》2011,3(4):268-277
Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological systems in arid areas.The spatial heterogeneity of soil water content is a major soil property,and a focus of soil science and hydrology.On the southern edge of the Tengger Desert,sample plots were selected from mobile sand dunes in desertified lands that had been enclosed for 5,15 and 25 years,respectively.This study explored the dynamic and spatial heterogeneity of soil water content in these different layers of soil that were also in the reversion process of desertification.The results showed that the soil water content of the mobile sand dunes was highest when in the initial stages of the reversion process of desertification,while the soil water content in the 0-20 cm,20-40 cm and 40-60 cm layers of soil was 1.769%,3.011%,and 2.967% respectively,presenting a restoring tendency after 25 years of enclosure.There were significant differences,as a whole,in the soil water content among different restoration stages and different soil layers,respectively.Changes in soil water content,in different soil layers,at different restoration stages,exhibited exponential or spherical patterns.The spatial distribution of soil water content exhibited a mosaic patch pattern with obvious spatial heterogeneity.The ratio of the heterogeneity of spatial autocorrelation to gross spatial heterogeneity was greater than 50%.The gross spatial heterogeneity of the 0-20 cm layer of soil improved gradually,while those of the 20-40 cm and 40-60 cm layers improved initially,then weakened in the reversion process of desertification.This study revealed that restoration with sand-binding vegetation reduced soil water content,and increased its spatial heterogeneity in arid areas.However,after 25 years of vegetation-soil system restoration,the soil water content started to increase and its spatial heterogeneity started to weaken.These results will further benefit the understanding of the ecological mechanism between soil water and sand-binding vegetation. 相似文献
999.
X-ray photoelectron spectroscopy(XPS) was applied to examine the N structures of soil humic substances and some of their analogues.It was found that for soil humic substances XPS method gave similar results as those obtained by ^15N CPMAS NMR (cross-polarization magic-angle spinning nuclear magnetic resonance) method.70%-86% of total N in soil humic substances was in the form of amide,and 6%-13% was presented as ammes,with the remaining part as heterocyclic N.There was no difference in the distribution of the forms of N between the humic substances from soils formed over hundreds or thousands of years and the newly formed ones.For fulvic acid from weathered coal and benzoquinone-(NH4)2SO4 polymer the XPS results deviated significantly from the ^15N CPMAS NMR data. 相似文献
1000.