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为了深入研究辣椒雄性不育与能量代谢之间的关系,该研究以辣椒近缘物种番茄的葡萄糖-6-磷酸脱氢酶基因(G6PDH)同源序列为基础,采用电子克隆的方法克隆出辣椒CaG6PDH基因。利用荧光定量PCR技术,对辣椒雄性不育系9704A与其保持系9704B花蕾发育的不同阶段,以及保持系9704B不同组织(茎、叶、花、果皮、胎座、种子)中CaG6PDH基因进行表达分析。结果表明:两系中获得的CaG6PDH基因的编码序列一致,全长1 533bp,编码510个氨基酸残基;辣椒CaG6PDH基因在保持系不同组织中表达量存在差异,胎座中表达量最高,茎中表达量最低;辣椒CaG6PDH基因的表达量在花蕾发育的不同阶段雄性不育系均高于保持系,此种差异在小孢子发育的单核期与成熟期尤为明显,这种差异可能使雄性不育系能量代谢供应出现异常,从而影响小孢子的正常发育而导致雄性败育。  相似文献   
3.
中国灌木辣椒种质遗传多样性的SRAP和SSR分析   总被引:3,自引:0,他引:3  
应用SRAP和SSR分子标记对8份辣椒种质进行了遗传多样性分析,结果表明,15对SRAP引物组合共扩增出321条带,平均每对引物扩增出21.40条,多态性位点比率为72.90%;18对SSR引物共扩增出109条带,平均每对引物扩增出6.06条,多态性位点比率为98.17%。与SRAP比较,SSR检测到的Shannon多样性指数(I)、观测等位基因数(Na)和有效等位基因数(Ne)等遗传多样性参数都较大,说明SSR有更高的多态性检测效率。基于SRAP的聚类与基于SSR的聚类之间存在极显著正相关,且都能将中国灌木辣椒种质与美洲灌木辣椒种质及一年生辣椒种质有效区分。  相似文献   
4.
We report in this study for the first time the occurrence of bacterial spot of pepper in Iran and both phenotypic and genetic characterization of its causal agent, Xanthomonas euvesicatoria. Pepper plants grown in 15 of 30 surveyed private gardens and commercial fields were infected by the pathogen in Marand County, East Azerbaijan Province, north‐western Iran. The obtained strains of X. euvesicatoria had different amylolytic and pectolytic activities compared with those reported for this species elsewhere. Pathogenicity tests showed that strains isolated from diseased pepper are able to infect tomato, in addition to pepper. Host range of the pathogen was assessed on eight annual plant species including crops and weeds by measuring the population dynamics. The host range assessment showed that in addition to pepper and tomato, known hosts of X. euvesicatoria, the Iranian strains were able to colonize a number of new hosts such as nightshade and common bean. In contrast, none of them were able to build up their population on cowpea, eggplant, bindweed and zucchini. All X. euvesicatoria strains obtained in this study were sensitive to copper sulphate and streptomycin at concentrations higher than 20 and 50 mg/l, respectively. Phylogenetic analyses of the strains using the sequences of gyrB and hrpB genes confirmed their species as X. euvesicatoria. Given a direct commercial trade of fresh solanaceous vegetables between Iran and Turkey, it is hypothesized that the pathogen entered north‐western Iran from eastern parts of Turkey through infected plant materials. Finally, the role of prevention – based on the use of healthy planting materials and resistant and/or tolerant plant varieties – to contain the potential disease epidemics is discussed.  相似文献   
5.
高效液相色谱法测定辣椒干中辣椒素的含量   总被引:5,自引:0,他引:5  
本文建立了简便、快速的分离测定辣椒干中辣椒素含量的高效液相色谱法.HPC的条件Burospher-100 C18柱(I.D.250 mm×4.6 mm,5μm);流动相为甲醇-水(7030,V/V);流速为0.6 mL/min;检测波长为280 nm.在上述条件下,辣椒素在1.01~121.2 mg/L的范围内线性关系良好,线性相关系数γ=0.9994;实验结果表明,该方法的相对标准偏差在1.38%(n=6)以内,平均回收率为99.88%.  相似文献   
6.
Direct shoot bud induction and plant regeneration was achieved in Capsicum frutescens var. KTOC. Aseptically grown seedling explants devoid of roots, apical meristem and cotyledons were inoculated in an inverted position in medium comprising of Murashige and Skoog (Physiol Plant 15:472–497, 1962) basal medium supplemented with 2-(N-morpholine) ethanesulphonic acid buffer along with 2.28 μM indole-3-acetic acid, 10 μM silver nitrate and either of 13.31–89.77 μM benzyl adenine (BA), 9.29–23.23 μM kinetin, 0.91–9.12 μM zeatin, 2.46–9.84 μM 2-isopentenyl adenine. Profuse shoot bud induction was observed only in explants grown on a media supplemented with BA (26.63 μM) as a cytokinin source and 19.4 ± 4.2 shoot buds per explant was obtained in inverted mode under continuous light. Incorporation of polyamine inhibitors in the culture medium completely inhibited shoothoot bud induction. Incorporation of exogenous polyamines improved the induction of shoot buds under 24 h photoperiod. These buds were elongated in MS medium containing 2.8 μM gibberellic acid. Transfer of these shoots to hormone-free MS medium resulted in rooting and rooted plants were transferred to fields. This protocol can be efficiently used for mass propagation and presumably also for regeneration of genetically transformed C. frutescens.  相似文献   
7.
 Hyperhydricity in regenerated pepper plants was monitored by the induction of the ER-luminal resident protein, as observed by immunoblotting. Immunoblotting of total protein using an anti-soybean BiP serum indicated that the induction and accumulation of an 80-kDa protein was related to BiP (Binding protein), a 78-kDa ER-resident molecular chaperone. The anti-BiP serum cross-reacted with an 80-kDa protein which was significantly induced by hyperhydricity. Based on similar molecular weight and immunological reactivity we concluded that the 80-kDa protein induced in hyperhydric plants is a BiP homologue. The ultrastructural organisation of leaves in non-hyperhydric and hyperhydric pepper (Capsicum annuum L.) plants was investigated with the aim of identifying the subcellular changes associated with this phenomenon. In non-hyperhydric leaves the chloroplasts of the palisade cells had normally developed thylakoids and grana and a low accumulation or absence of starch grains and plastoglobules. In the hyperhydric plants, however, the chloroplasts exhibited thylakoid disorganisation, low grana number, an accumulation of large starch grains and a low accumulation or absence of plastoglobules. Although the structure of mitochondria and peroxisomes did not change in hyperhydric plants, the number of peroxisomes did increase. Received: 23 July 1998 / Revision received: 26 February 1999 / Accepted: 17 March 1999  相似文献   
8.
QTL mapping of fruit-related traits in pepper (Capsicum annuum)   总被引:11,自引:0,他引:11  
QTL analysis of pepper fruit characters was performed in an F3 population derived from a cross between two Capsicum annuum genotypes, the bell-type cultivar Maor and the Indian small-fruited line Perennial. RFLP, AFLP®1, RAPD and morphological markers (a total of 177) were used to construct a comparative pepper-tomato genetic map for this cross, and 14 quantitatively inherited traits were evaluated in 180 F3 families. A total of 55 QTL were identified by interval analysis using LOD 3.0 as the threshold for QTL detection. QTL for several traits including fruit diameter and weight, pericarp thickness and pedicel diameter were often located in similar chromosomal regions, thus reflecting high genetic correlations among these traits. A major QTL that accounts for more than 60% of the phenotypic variation for fruit shape (ratio of fruit length to fruit diameter) was detected in chromosome 3. This chromosome also contained QTL for most of the traits scored in the population. Markers in linkage groups 2, 3, 8 and 10 were associated with QTL for multiple traits, thereby suggesting their importance as loci that control developmental processes in pepper. Several QTL in pepper appeared to correspond to positions in tomato for loci controlling the same traits, suggesting the hypothesis that these QTL may be orthologous in the two species.  相似文献   
9.
Soybean 7S and 11S globulins were stored at relative humidities (RHs) of 11% and 96% at 50°C. The redispersibility of the proteins at RH 96% decreased in a short time. However, it did not decrease, when stored for 45 days at RH 11%. Gel filtration showed that the proteins polymerized during storage. The effects of urea, sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) on the redispersibilities of the proteins at RH 96% showed that the hydrogen, hydrophobic and disulfide bonds participate in the polymerization of 7S globulin, and that the disulfide bond is strongly related to the polymerization of 11S globulin. Redispersibility was restored with 2-ME in both the 7S and 11S globulins and some of the proteins in the supernatant redispersed with 2-ME were observed to be similar to the native ones with respect to the gel filtration, electrophoretic behavior and circular dichroism spectrum.  相似文献   
10.
Horticultural crop production and changes in physiological aspects during the growing season may be affected by climate change factors (CC), which include increased temperature and the associated doubling or tripling of atmospheric CO2 concentrations. However, the potential effects are complex and many parameters might impact on the observed effects. To evaluate the effects of CC, the growth, yield, fruit characteristics, photosynthetic traits, and morphological characteristics of hot peppers were investigated. The hot peppers were grown under two CC scenarios, with the Representative Concentration Pathway (RCP) of 4.5 (Temp.; +3.4°C, CO2 conc.; 540 μmol/mol, Precipitation +17.3%) and RCP 8.5 (Temp.; +6.0°C and CO2 conc.; 940 μmol/mol, Precipitation +20.3%), respectively, using extreme weather simulators. This was compared with existing weather conditions occurring in Jeonju, South Korea in terms of air temperature, relative humidity, radiation, and precipitation. Overall, the plant height showed the highest under moderate CC conditions (RCP 4.5) among all the treatments tested. The number of leaves in the RCP 8.5 condition showed 7,739/plants, which was 2.2 times higher than that of the control. In addition, fruit shape was shortened and percentage dry matter was also the highest. The yield of hot pepper in the CC RCP 4.5 and 8.5 conditions were decreased by 21.5% and 89.2% when compared with that of the control, respectively. The days to harvest in the condition of CC scenarios were shortened from 5 to 13 compared with that of control, predominantly due to the increased air temperature. The results indicated that the severe RCP CC scenarios made reduction in the yields and negative affection on the fruit qualities. Overall, hot pepper was tolerant of mild CC scenarios of temperature × CO2 but was significantly affected by more extreme CC interacting parameter concentrations (or similar).  相似文献   
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