不同基因型芥菜对5种重金属累积差异性研究

探究不同基因型芥菜对镉(Cd)、砷(As)、铅(Pb)、汞(Hg)和铬(Cr) 5种重金属的累积差异性,为芥菜在重金属复合污染地区生产的安全性提供指导。通过盆栽试验研究9种不同基因型芥菜对5种重金属复合污染的响应差异,并结合重金属富集系数和转运系数以及单因子污染指数法、内梅罗综合污染指数法综合评价芥菜在重金属污染区的生产安全性。结果表明：芥菜具有较强的茎/叶重金属转运能力,重金属主要累积在芥菜根及叶中。芥菜不同部位重金属Cd的单项污染指数普遍较高且存在较大的品种差异。Pb、As、Hg和Cr污染指数呈现趋势类似,品种及不同部位间差异不明显。供试品种中‘五四青丕蓝’、‘脆嫩儿菜’、‘特大棒菜’、‘抗热四季甜竹芥’为较好的重金属低累积芥菜品种。芥菜对重金属的累积有基因型差异和重金属种类差异,通过筛选不同基因型芥菜可以获得生产上较为安全的品种。     

不同基因型烤烟中性致香物质含量差异性分析

采用GC-MS 测定方法,对贵州4 个基因型烤烟的中性致香物质类胡萝卜素降解产物、苯丙氨酸类、类 西柏烷类、新植二烯的含量进行分析测定。结果表明;毕纳1 号、贵烟1 号、贵烟2 号烤后烟叶中性致香物质总量明 显高于K326;毕纳1 号烤后烟叶中性致香化物质总量、类胡萝卜素降解产物含量、苯丙氨酸类含量、类西柏烷类和新 植二烯含量均最高,其中新植二烯含量显著高于K326,类胡萝卜素降解产物含量显著高于贵烟2 号;贵烟2 号和贵 烟1 号中性致香物质总量高于K326,主要是因其新植二烯含量的增加所致。     

不同种衣剂在中稻深两优5814苗期应用效果研究

为了探索种衣剂在杂交水稻苗期的应用效果,采用2.5%吡窑咪、3%恶窑咪、锐胜和适乐时包衣深两优5814 种子,测定发芽率,调查成秧率、秧苗素质及稻蓟马防效。结果表明院锐胜与3%恶窑咪能提高种子发芽率,但4种种衣剂 处理的种子的成秧率无明显差异;各处理组的株高、叶面积和总根数与对照相比无明显差异,但锐胜处理组的株高大 于3%恶窑咪处理组、叶面积大于2.5%吡窑咪处理组、总根数大于3%恶窑咪和2.5%吡窑咪处理组、苗干重大于2.5%吡窑咪 处理组,秧苗的综合素质以锐胜处理组为佳;各种衣剂对稻蓟马均有防效,其中锐胜和2.5%吡窑咪处理组的防效较好。     

上海地区奶牛乳房炎金黄色葡萄球菌基因分型与耐药性研究

通过对分离自上海4个规模化奶牛场的63株奶牛乳房炎金黄色葡萄球菌进行基因分型和耐药性分析,研究金黄色葡萄球菌基因型在上海地区的分布情况及其耐药情况,并分析基因型和耐药性两者之间的相关性。结果显示,利用RAPD技术对63株金黄色葡萄球菌进行基因分型,共分为9个基因型,其中以Ⅵ型为主,占总数的47.62%。各个奶牛场的基因型分布差异显著,Z奶牛场和D奶牛场基因型分布较平均,而W奶牛场和X奶牛场基因型分布较集中。63株金黄色葡萄球菌对各种常用抗生素均产生不同程度的耐药性,尤其对氨苄西林和阿莫西林已完全耐药,各个奶牛场的菌株对不同抗生素的耐药性差异较大。对金黄色葡萄球菌的基因型和耐药性进行比较发现两者之间没有显著的相关性。     

The difference in the formation of thermotolerance of two cotton cultivars with different heat tolerance

ABSTRACT

In order to study the mechanism of thermotolerance of cotton cultivars with different heat tolerance, the response of yield component and photosynthesis to short-term heat stress (HT; average temperature 34°C) was studied. Pot experiments were carried out in 2015 and 2016 by using cotton cultivar PHY370WR (heat tolerant cultivar) and Sumian15 (heat susceptible cultivar). Results showed that heat (34°C) treatment resulted in a significant (p < 0.05) reduction in cotton yield. Path analysis showed that the direct path coefficient (0.89) of boll weight was higher, compared with the boll number (0.46). With high-temperature stress, it was the difference of boll weight reduction contributed the majority to the difference of yield reduction between cultivars, not the difference of boll number reduction. Different decrease in photosynthesis between cultivars leads to the different decline in boll weight. Different thermotolerance between the two cultivars were as follows: the heat tolerant cultivar could maintain higher photosynthesis rate under HT, and it could recover more quickly and highly in photosynthesis than the heat susceptible cultivar. More importantly, the leaf functional period of heat tolerant cultivar was less shortened by HT than that of heat susceptible cultivar.     

The effect of the ‘Gait keeper’ mutation in the DMRT3 gene on gaiting ability in Icelandic horses

A nonsense mutation in DMRT3 (‘Gait keeper’ mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild‐type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the frequencies of the A‐ and C‐ alleles have changed in the Icelandic horse population in recent decades. It was confirmed that homozygosity for the DMRT3 nonsense mutation relates to the ability to pace. It further had a favourable effect on scores in breeding field tests for the lateral gait tölt, demonstrated by better beat quality, speed capacity and suppleness. Horses with the CA genotype had on the other hand significantly higher scores for walk, trot, canter and gallop, and they performed better beat and suspension in trot and gallop. These results indicate that the AA genotype reinforces the coordination of ipsilateral legs, with the subsequent negative effect on the synchronized movement of diagonal legs compared with the CA genotype. The frequency of the A‐allele has increased in recent decades with a corresponding decrease in the frequency of the C‐allele. The estimated frequency of the A‐allele in the Icelandic horse population in 2012 was 0.94. Selective breeding for lateral gaits in the Icelandic horse population has apparently altered the frequency of DMRT3 genotypes with a predicted loss of the C‐allele in relatively few years. The results have practical implications for breeding and training of Icelandic horses and other gaited horse breeds.     

鸡传染性支气管炎强毒分离株遗传进化分析和免疫保护试验

从山东省发病鸡群中分离鉴定了一株鸡传染性支气管炎病毒（Infectious bronchitis virus,IBV）强毒株SDIB821/2012,对其进行S1基因序列测定分析和免疫保护试验。S1基因遗传进化分析结果显示,SDIB821/2012属于以QXIBV为代表的基因型,与同属一个基因型的IBV参考株氨基酸同源性为91.6%～98.5%,与疫苗株491同源性为77.6%,与H120和MA5同源性均为74.8%。免疫保护试验结果显示,根据试验鸡临床症状和发病死亡情况,弱毒活疫苗491对SDIB821/2012的保护率为90%,而H120和MA5对SDIB821/2012的保护率分别仅为40%和33%。攻毒后各免疫组喉头、泄殖腔棉拭样品以及气管、肺脏和肾脏组织均可检测到病毒,表明3种IB疫苗均不能对SDIB821/2012提供完全的免疫保护。     

广西甘蔗黄叶病调查及3种病毒基因型在广西的分布

[目的]探明甘蔗黄叶病在广西蔗区的发生情况,明确甘蔗黄叶病毒（SCYLV）基因型类型和地理分布,为甘蔗抗病育种和健康种苗生产提供科学依据.[方法]从广西蔗区采集不同品种（品系）显症或不显症甘蔗样品,采用特异引物（P1/P2）进行RT-PCR检测.甘蔗黄叶病病毒基因型鉴定采用3对特异引物BRA-PER-F/BRA-PER-R、REU-F/B-REVd和CUB-F/CUB-R进行RT-PCR鉴定.[结果]SCYLV RT-PCR检测结果,124个样品中有57个样品可扩增出大小约630 bp的目的条带,扩增产物与GenBank中已报道的SCYLV CP基因序列同源性达95％～99％.甘蔗黄叶病调查结果,124个样品中57个样品检测出SCYLV,感染率为46.0％.广西北部蔗区黄叶病感染最严重,SCYLV检出率为76.0％;桂西、桂中、桂南蔗区分别有50.0％、40.0％和36.8％的品种检出SCYLV;桂东蔗区SCYLV阳性检测率最低,为16.6％.在所调查的甘蔗品种中以柳城03-182、桂糖21、粤糖55和粤糖93-159感染SCYLV比较严重,主栽品种ROC22在柳城、宜州、钦州和金光农场均检测出阳性.病毒基因型调查结果,广西甘蔗黄叶病病毒基因型存在巴西-秘鲁（BRA-PER）、留尼汪岛（REU）和古巴（CUB）基因型等3种.主要以CUB型为主,占63.2％,除东部和西部蔗区外其他蔗区均有分布;其次是BRA-PER基因型,占56.1％,每个生态蔗区均有分布;REU基因型占5.3％,分布于柳州、凭祥、南宁蔗区.[结论]甘蔗黄叶病SCYLV已在广西各主要蔗区发生且蔓延,其病毒基因型存在3种且有不同程度分布.     

Genetic (co)variance components across age for Show Jumping performance as an estimation of phenotypic plasticity ability in Spanish horses

The purpose of this study was to study phenotypic plasticity ability for Show Jumping performance in horses according to age differences. For this study, 11 352 participations, belonging to 1085 horses grouped by age (4‐, 5‐ or 6‐year olds), were analysed. repeatability animal models (RAM) and multiple trait animal models (MTAM) were compared. RAM assumed the same covariance components for all age groups, whereas MTAM considered the results of every animal at every age group as different (but correlated) traits. The age, sex, starting order and training level were included as fixed effects. The random effects were the animal, the individual permanent environment, the competition and the rider. Six models were compared, and the rider–horse interaction was added as a random effect; furthermore, heterogeneous residual variance was taken into consideration only for MTAM. The study of the genetic correlations between age groups highlighted the presence of an age–genotype interaction and, therefore, an underlying environmental effect. This study may allow us to select horses with a plastic response, which show either a gradual response or a precocious response and thus gain or lose genetic potential with age, respectively.     

Reaction of six Musa genotypes to root-parasitic nematodes

The reaction of six Musa genotypes to root-parasitic nematodes was evaluated under field conditions, together with the horizontal, and vertical distributions of the neomatodes within the soil profile. The numbers of Radopholus similis, Helicotylenchus spp., Meloidogyne spp. and of all nematodes in the excavated soil quadrant varied with Musa genotype. All genotypes were very susceptible to at least one nematode. Yangambi km5, Pisang Jari Buaya and FHIA-23 supported the lowest number of R. similis and Pisang Jari Buaya, the lowest number of Helicotylenchus spp. These three cultivars supported high numbers of Meloidogyne spp. Furthermore, FHIA-23 supported high numbers of Helicotylenchus spp. The horizontal and vertical distributions of R. similis in the root system of Valery, Gros Michel and FHIA-18 were very similar. By constrast, the distributions of Helicotylenchus spp., Meloidogyne spp. and the number of all nematodes varied slightly among the genotypes. Because Musa genotypes susceptible to a particular nematode showed a similar horizontal and vertical nematode distribution with populations concentrated in the vicinity of the plant base (0–30 cm horizontal distance and 30 cm depth), sampling at this site would be sufficient for the identification of the Musa plant reaction.