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971.
东农611是以3-1028为母本,以3-1030为父本配制而成的中早熟甘蓝一代杂种。叶球近圆形,外叶灰绿色,表面平滑,中肋细,叶球紧实度高,中心柱小于球高的1/2,叶质脆嫩,VC含量452.3 mg·kg-1,抗TuMV和黑腐病,单球质量2 kg左右,每667 m2产量5 000 kg左右,适于黑龙江、吉林、内蒙古东北部等地春、秋早熟栽培。  相似文献   
972.
Red Chinese sand pears (Pyrus pyrifolia Nakai) are particular to China. In order to determine the effects of fruit bagging treatments (including bag types, bag removal patterns and dates) on fruit qualities and to understand the mechanism of coloring of red Chinese sand pears, two experiments were carried out. In the first experiment, fruit of ‘Meirensu’ were firstly covered by light-impermeable paper bags with different levels of light permeable liners during their early development stage, then, the whole bag were/not removed or only the outer layer of bags were removed 3, 2 or 1 weeks before harvest. Thus, the fruit were/not totally re-exposed or were under different levels of sunlight transmission (80.31% or 34.71%). Non-bagged fruit were used as the control. Bagging treatments significantly affected the concentration of anthocyanin and the visual qualities of pear fruit. Compared to control, fruit re-exposed totally for 2 or 3 weeks accumulated the largest amount of anthocyanin and fruit receiving 80.31% and 34.71% of sunlight for 1–3 weeks could synthesize a little anthocyanin, indicating that high light intensity is imperative for coloring in red Chinese sand pears. Bagging treatments did not affect contents of total soluble sugars, but decreased organic acids contents in fruit. In the second experiment, fruit of ‘Meirensu’ and ‘Yunhongli No. 1’ were covered with only one type of light-impermeable bag during the early development stage and totally re-exposed after the bag removal 15 days before harvest. Fruit were then collected at different intervals to trace the time-course of coloring, and related physiology and inner qualities. With increasing time after the bag removal, the concentration of chlorophyll, carotenoid, flavonoid and total phenols changed little, but the concentration of anthocyanin accumulated extremely fast within 10 days after the bag removal in both cultivars and thereafter kept constant. ‘Yunhongli No. 1’ had higher anthocyanin contents and lower hue angle than ‘Meirensu’, indicating a higher potential of anthocyanin synthesis. After the bag removal, the sucrose contents and PAL activities increased gradually and correlation analysis revealed that they were highly correlated with anthocyanin accumulation in two cultivars. This study suggests that anthocyanin biosynthesis in red Chinese sand pears is a highly light dependent process and modified by genotypes. Based on the current results, in order to obtain red Chinese sand pear fruit with attractive appearance and good inner qualities, fruit must be covered with light-impermeable bags at the early stage of fruit development and the bag should be removed totally at least 10 days before harvest.  相似文献   
973.
富士苹果AFLP体系的优化及其在鉴定早熟芽变中的应用   总被引:4,自引:0,他引:4  
 以‘长富2号’苹果为材料,采用优化的AFLP技术对其早熟芽变与母株进行初步研究,筛选了64对引物,其中43对引物扩增结果理想,共产生了2,700条带。有4对引物在芽变与母株之间产生了7条差异片段,主要集中在350~800 bp之间。研究表明早熟芽变是由于遗传物质改变造成的,同时也说明利用该体系对苹果芽变进行分析和鉴定获得成功。  相似文献   
974.
AIM: To explore the effects of sodium butyrate, activin A and dexamthasone on inducing mouse embryonic stem (ES) cells to differentiate into exocrine pancreatic cells in vitro. METHODS: E14 mouse ES cells were cultured in suspension to form embryonic bodies (EBs). The EBs were cultured with differentiating medium containing different concentrations of sodium butyrate, and the spontaneously differentiated ES cells were used as control. Exocrine pancreatic genes such as amylase, chymotrypsinogen, elastase 1, elastase 2 and carboxypeptidase were detected by RT-PCR at different time points to determine the optimal concentration and exposure time of sodium butyrate. Furthermore, activin A or dexamthasone was also used to explore the effects on exocrine differentiation. After that, the combination of sodium butyrate, activin A and dexamthasone was used to promote the differentiation of exocrine pancreatic cells from ES cells. During the differentiation course, the gene expressions of amylase, chymotrypsinogen, elastase 1, elastase 2 and carboxypeptidase were detected by RT-PCR. Morphological changes were investigated by phase contrast microscopy. Amylase expression was examined by immunofluorescence staining. RESULTS: Exocrine pancreatic gene expressions such as amylase, chymotrypsinogen, elastase 1, elastase 2 and carboxypeptidase were detected in spontaneously differentiated EBs. A relatively lower concentration of sodium butyrate with a shorter exposure time significantly promoted those above gene expressions as compared to that of spontaneously differentiated EBs. Activin A and dexamethasone induced upregulation of exocrine gene expression. The combination of activin A, sodium butyrate and dexamethasone significantly enhanced the mRNA levels of amylase, chymotrypsinogen, elastase 1, elastase 2 and carboxypeptidase. Under the treatment of activin A, sodium butyrate and dexamethasone, differentiated cells were polygonal in shape with large, round, and center-situated nuclei. According to the observation of immunofluorescence staining, amylase was positive expressed at the final stage. CONCLUSION: These data indicate that exocrine pancreatic differentiation of ES cells is induced by sodium butyrate, activin A and dexamethasone. The combination of pancreatic inducing factors improves the differentiating efficiency.  相似文献   
975.
AIM: To investigate the effect and the mechanism of apolipoprotein (a) [apo (a)] on proliferation of vascular smooth muscle cells (VSMCs). METHODS: All VSMCs used in experiments were serial subcultured from primary cells and were identified by immunohistochemistry staining of α-actin. Cell growth assay was observed as cell counting and MTT assay. Western blotting was also employed to detect the related mechanism. RESULTS: All cells used in experiments were confirmed as VSMCs. Although apo (a) enhanced VSMCs proliferation, this effect was attenuated by anti-integrin αⅤβ3, LM609. Use these reagents alone had no effect on VSMCs growth. The results of Western blotting demonstrated that focal adhesion kinase (FAK) was activated by apo (a) and the expression of total or phosphorylated transforming growth factor β1 (TGF-β1) was also decreased. However, these effects described above were all blocked by LM609. CONCLUSION: Apolipoprotein (a) enhances VSMCs proliferation and this effect is mediated by integrin αⅤβ3, which activates FAK and attenuates TGF-β1 and phospho-TGF-β1 expression.  相似文献   
976.
沼渣基质对温室番茄生长和产量的影响   总被引:5,自引:1,他引:4  
利用沼渣和炉渣以不同体积比混合作基质,研究沼渣对温室番茄生长和产量的影响。结果表明,沼渣和炉渣复合基质的理化性状完全达标;沼渣促进了番茄植株的生长,提高了番茄果实产量和品质,其中,3份沼渣+1份炉渣处理的番茄植株根系活力最强,前3穗果实产量最高;为0.93 kg·株-1;糖酸比最高,为6.24。  相似文献   
977.
秋播小型大白菜新品种京秋娃娃菜的选育   总被引:2,自引:1,他引:1  
京秋娃娃菜是由两个自交不亲和系配制而成的秋播小型大白菜一代杂种。成熟期55 d(天),株型半直立,株高32 cm,开展度36 cm,叶色绿,外叶数8片,球叶数38片;叶球合抱,筒形,球色绿,内叶浅黄色,叶球高24 cm,直径10 cm,球形指数2.4,叶球质量0.6 kg左右,净菜率62.4 %。每667 m2净菜产量约5 000 kg。高抗病毒病,抗霜霉病和黑腐病。适合北京、河北、山东、辽宁、黑龙江、吉林、内蒙古等地秋季栽培,目前累计推广面积400 hm2。  相似文献   
978.
采用土培法,研究了不同浓度的外源铬(0、2、8、15、25 mg/kg)对2个豇豆品种幼苗生长的影响.结果表明:低浓度的外源铬(2 mg/kg)对2个豇豆品种幼苗的株高、地上部鲜重有显著促进作用;高浓度的外源铬(15 mg/kg)对2个品种幼苗的株高、主根长起显著或极显著的抑制作用,对特抗病高产四号的地上部鲜重、叶面积有极显著抑制作用.综合各项指标,特抗病高产四号比丰产一号对铬敏感.  相似文献   
979.
阐述了桃儿七的生存现状,针对其濒危原因,提出了具体的保护途径,为合理开发利用桃儿七资源提供依据.  相似文献   
980.
蝴蝶兰种子无菌播种诱导增殖原球茎试验研究   总被引:2,自引:0,他引:2  
利用不同激素浓度及添加物对蝴蝶兰未成熟胚有效原球茎进行诱导研究.结果表明:进行无菌播种采收未开裂的果荚比已开裂的要有利的多,采摘最佳时间为授粉后120 d;原球茎增殖效果最佳的激素组合是BA 3.0+NAA 0.2;200 mL/L椰乳对蝴蝶兰PLB增殖的影响效果最好,其次为香蕉和马铃薯.  相似文献   
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