运用SRAP分子标记鉴定辣椒杂交种纯度

摘要：以辣椒品种航椒4号和航椒5号及其亲本H09-4、H09-2、WS-3、B-2-2为试验材料,运用SRAP分子标记技术研究了辣椒杂种与其亲本之间 扩增条带的多态性,鉴定和分析了航椒4号辣椒品种的真实性。结果表明,所试验的18对SRAP引物中有13对引物分别在2个辣椒杂交种和其亲本之间存在扩增条带的多态性,平均每个引物组合扩增的清晰条带数为23.5条,多态性比率为58.89%,其中有3条偏母型引物,2条偏父型引物, 2条互补型引物。用互补型引物DC1-EM9对航椒4号和航椒5号进行了各100粒种子SRAP鉴定,所测纯度分别为100%和97.3%,与田间纯度100%和98.9%非常接近,表明了SRAP分子标记技术是鉴定辣椒一代杂种纯度的有效方法,具有准确、可靠、快速的特点,在辣椒杂交种子纯度室内快速检测中有很大的应用前景。     

DNA profiling of Capsicum landraces of Manipur

Seven chilli landraces of Manipur belonging to three cultivated species of Capsicum (Capsicum annuum, Capsicum frutescens, and Capsicum chinense) form economically important food crops of the region. The genotypes were characterized using ten random amplified polymorphic DNA (RAPD) markers. The cluster analysis based on Jaccard's similarity coefficient calculated by UPGMA method differentiated the genotypes into two main cluster groups. One cluster represented the C. annuum genotypes while the other cluster represented the C. frutescens and the C. chinense genotypes. C. chinense genotypes were more close to C. frutescens genotypes. Genetic variation between the C. frutescens genotypes was more than among the C. annuum genotypes and the C. chinense genotypes were the least similar ones.     

Characterization of a new fungal antagonist of Phytophthora capsici

The capacity of many microorganisms for antagonism towards pathogens is unknown and previously uncharacterized species may be potentially useful in this respect. This work presents the evaluation of the capacity of a previously uncharacterized Ascomycete, denominated here as UA to protect chili pepper (Capsicum annuum) against Phytophthora capsici, and other soil-borne plant pathogens and establishes the role of UA as a biocontrol agent. Inoculation of UA 2 days before the inoculation of P. capsici led to 77.8% survival of pepper plants. Simultaneous confrontation of both microorganisms in vitro led to 53.1% growth inhibition of P. capsici, while the inoculation of P. capsici 3 days after the inoculation with UA improved growth inhibition up to 73%. Simultaneous confrontation in vitro of UA with Fusarium oxysporum and Fusarium solani led to 41.2 and 50% growth inhibition, respectively, but had no effect on Rhizoctonia solani or a binucleate Rhizoctonia isolate. Moreover, formation of zoosporangia and the germination of zoospores were completely inhibited by exposure to undiluted filter sterilized filtrate. UA produces septate mycelia, but could not be classified in detail due to a lack of spores or reproductive structures. However, sequencing of Internal Transcribed Spacer 1, 2 and the 5.8S genes indicated that this fungus is a member of the Ascomycetes.     

早中熟优质辣椒新品种‘粤研1号’

‘粤研1号’辣椒是早中熟优质杂交一代新品种,青果绿色,熟果大红色,果实长羊角形,果面微皱,有光泽。果长17.7 cm,果宽3.2 cm,肉厚0.32 cm,单果质量54.7 g,心室2 ~ 3,微辣。商品性好,耐贮运,品质佳。田间表现高抗病毒病、炭疽病、疫病、青枯病。适合在华南地区、江苏、河南、黑龙江等地露地栽培。     

辣椒花器性状的遗传分析

估算辣椒(Capsicum annuum L.)花器性状的遗传变异系数和遗传力,结果表明,柱头外露长、柱头宽和花宽的遗传变异系数较大,花宽、花长/花宽、花药长和柱头宽的遗传力较大,且遗传型变异系数较大的性状,它的遗传力不一定大。相关和通径分析结果表明,辣椒柱头外露长与花长、柱头长和花长/花宽间的遗传相关达显著或极显著水平,大多数情况下都是遗传型相关系数绝对值大于表型相关系数绝对值,花宽和花长/花宽对柱头外露长的直接作用较大。估算26个辣椒品种、9个花器性状的主成分值,并将其分为6类,数量分类的结果符合实际情况。当主成分的特征值的累计贡献率接近85%时,主成分值就能基本反映花器性状的遗传特征。比较不同的系统聚类方法,离差平方和法较好地适合用于辣椒品种花器性状的数量分类。     

Fertilizer rate and β-galactosidase and peroxidase activity in pepper fruit at different stages and years of harvest

Beta-galactosidase and peroxidase are enzymes reported to have roles in pepper maturation. Fertilizer rate may affect activity of these enzymes in fruit maturing on the plant. Nine pepper cultivars, five non-pungent and four pungent, were fertilized at two rates in field plots in 1997 and 1998 at Lane, OK, USA. Fruit were harvested at mature green, turning, and red color developmental stages, and assayed for beta-galactosidase and peroxidase activity. Overall fruit beta-galactosidase activity increased as fertilizer rate increased, and was highest in red fruit. Fertilizer rate and fruit developmental stage did not affect peroxidase activity in 1997, but peroxidase activity was highest in red fruit in 1998. Enzyme activity appeared to be cultivar dependent, and patterns differed in both years. Activities of both enzymes were higher at the red stage in many of the non-pungent peppers than in pungent peppers. These data suggest that increased fertilizer affects the activity of at least one enzyme in fruit maturing on the plant. Cultural practices affecting enzyme activity may be used to modify concentrations of components in plants that are important for human consumption.     

不同辣椒变种的核型观察

对5个辣椒栽培变种进行核型观察分析,初步认为它们的核型公式是:灯笼椒为2n=24=18m+4Sm+2Sm(SAT);簇生椒、樱桃椒、圆锥椒为2n=24=20m+2Sm+2Sm(sAT);长椒为2n=24=20m+2Sm+2St(SAT)。按照 Stebbins 的核型不对称性分类,簇生椒、樱桃椒、圆锥椒及长椒皆属于2A 型,灯笼椒则属于2B 型。由此认为,从进化趋势及亲缘关系看,灯笼椒为最进化或特化的类型,其余4种则为相对原始的类型,且依次为簇生椒、樱桃椒、长椒、圆锥椒。     

低温对辣椒叶面积及生理指标的影响

对耐寒性不同的两个辣椒品种进行不同时间低温处理,研究其叶面积及叶片中的Pro含量、POD活性和MDA含量的变化规律。结果表明:低温减小了辣椒叶面积,且低温时间越长,减小幅度越大;随着低温时间的增加,辣椒叶片中的Pro含量、POD活性、MDA含量均呈不断增加趋势。     

硅对不同辣椒品种生理特性、镉积累及化学形态的影响

采用盆栽试验方法研究了重金属Cd（10 mg?kg-1）胁迫下,叶面喷施有机Si和无机Si对不同辣椒品种生长、抗氧化酶活性及辣椒体内Cd形态和积累量的影响。结果表明：在Cd污染（10 mg?kg-1）土壤上,2个辣椒品种对叶面喷施有机Si或无机Si的反应不同。喷施Si后,世农朝天椒的果实干质量较对照分别增加28.1 %、11.4 %,艳椒425的果实干质量较对照分别降低了32.3 %、55.1 %;喷施Si提高了辣椒叶片CAT和POD活性;辣椒果实中Cd的形态以FNaCl>FHAC>FE>FHCl>>FW>Fr,喷施Si明显降低了世农朝天椒果实中乙醇提取态Cd、氯化钠提取态Cd含量和Cd总提取量,增加了艳椒425果实中氯化钠提取态Cd、醋酸提取态Cd含量和Cd总提取量;辣椒中Cd积累量以茎>根或叶>果实,叶面喷施有机Si或无机Si明显减少Cd在2个辣椒品种果实中的蓄集,艳椒425和世农朝天椒果实Cd积累量降幅分别为19.1 %、23.3 %和13.4 %、26.1 %;在相同处理条件下,辣椒果实中Cd的含量和积累量均以艳椒425>世农朝天椒。     

Response of pepper plants to NO3:NH4 ratio and light intensity

Pepper plants were hydroponically grown in a growth chamber with two levels of light intensity (300 and 240 w/m² ) and two N0₃:NH₄ ratios (100:0 and 80:20). Plants supplied with both N forms (80:20) under high light conditions showed a decrease of nutrient uptake and produced low plant weight and yield compared to the all NO₃ treated plants. By contrast, plants receiving both N forms (80:20) with light reduced over 25% showed a growth and yield slightly superior to plants supplied with N0₃ as sole source of N. This suggests a significant light intensity‐N form interaction that favors all NO₃ nutrition for pepper at high light intensities.