根系修剪和接种丛枝菌根真菌对枳实生苗根系形态的影响

为探究根系修剪和接种丛枝菌根(AM)真菌对柑桔根系和植株生长的影响,以盆栽实生枳幼苗为试材,对根系修剪(切除1/2主根)和接种不同AM真菌(Diversispora versiformis、Funneliformis mosseae和Rhizoglomus intraradices)处理后植株生物量和根系形态变化进行了比较研究。结果表明,除D.versiformis外,根系修剪能显著提高F.mosseae和R.intraradices的侵染率。根系修剪降低了非菌根化植株地上部干重和植株总干重,但接种F.mosseae和R.intraradices后植株地上部干重、根系干重和植株总干重均显著增加,且接种F.mosseae的效果更好。根系修剪显著降低了植株主根长度,但三级侧根数量和一级侧根密度均显著增加,根系修剪下接种F.mosseae增加侧根数量和一级侧根密度的总体效应最优。根系修剪后接种F.mosseae和R.intraradices的植株根系表面积、投影面积和体积均显著增加,并增加了0～1.5 cm短根系的总长度。根系修剪和AM真菌对枳侧根的发生存在一定的叠加效应。     

Comparative analysis of different methods revealing the involvement of proteins during ageing of rice seeds

Seed longevity is a very important characteristic controlling seed quality. However, the mechanism underlying this characteristic is poorly understood. In this study, 'FH7185', a storable rice variety, the germination rate of which was 66.63%, much higher than the control after artificial ageing under relative humidity 88% and 42°C for 21 days. Different methods were applied to reveal the involvement of proteins during ageing of rice seeds. In total, 35 differential proteins were identified from 2D‐PAGE, and 3,719 proteins from iTRAQ analysis. A comparison of these two methods showed that not all protein types could be detected on the 2D‐PAGE gels, and the dynamic range was somewhat limited. So the comprehensive proteome map from the iTRAQ analysis was used to identify the quantitatively regulated proteins that played roles in seed longevity, and found that the most marked change was the increased abundance of many metabolic enzymes, especially the ones involved in α‐linolenic acid metabolism in the embryos during ageing. OsLOX2 and OsLOX3 had a negative effect on seed longevity, which were lower in FH7185 than the control. The dehydrogenase (LOC_Os07g44430) which played a major catalytic role in lipid peroxidation, also changed significantly during ageing. Therefore, OsLOX2, OsLOX3 and Loc_OS 07G44430 may be involved in the regulation of seed longevity with a synergistic effect.     

Identification and verification of quantitative trait loci for eating and cooking quality of rice (Oryza sativa)

This study was conducted to identify new quantitative trait loci (QTLs) that have stable effects for eating and cooking quality (ECQ) of rice. Three recombinant inbred line populations of indica rice were each planted in two years. Three traits for ECQ, amylose content (AC), gel consistency (GC) and alkali spreading value (ASV), were measured for QTL analysis. A total of 13 QTLs were detected, including four for AC, six for ASV and three for GC. Two QTLs, qGC4 in the interval RM16252–RM335 on the short arm of chromosome 4 and qGC6.2 in the Alk region, were validated in a population derived from a residual heterozygote that was homozygous at the major locus Wx. In the absence of segregation at the Wx locus, qGC4 and qGC6.2 had additive effects of 2.46 and 8.18 mm, respectively, offering a potential for improving GC property of rice varieties. Comparison between qGC4 and previous results suggests that qGC4 is likely a new QTL for GC, providing a candidate for gene cloning and functional characterization.     

利用因子分析综合评价9个西藏农家青稞品种的品质

随着青稞加工产业的发展,筛选西藏优质种质资源将有助于培育适宜加工的青稞品种。选取9个西藏农家青稞品种,以藏青25为对照,通过测定31项化学特性指标,建立品质综合评价体系。结果表明:经因子分析提取出6个特征值大于1的主成分,累积方差贡献率为94.65%,其中第1主成分的贡献率为49.81%,主要包含蛋白质及苏氨酸（THR）、脯氨酸（PRO）、丙氨酸（ALA）、缬氨酸（VAC）、亮氨酸（LEU）、苯丙氨酸（PHE）、组氨酸（HIS）、赖氨酸（LYS）、清蛋白、总氨基酸含量等指标;第2主成分的贡献率为13.85%,其中粗脂肪、直链淀粉、膳食纤维、γ-V_E、磷含量具有较大的载荷值。根据建立的品质综合评价模型,优良度得分排序为:藏青25>青21>隆子黑>拉萨长黑>联嘎木>拉萨短白>彭乃嘎布>江热俄久>直孔嘎夏>联木白稞。     

镉胁迫对烟草种子萌发和烟苗生长发育的影响

为探讨不同镉（Cd）胁迫对不同烟草品种种子萌发、幼苗生长的生理生态效应的影响,以吉烟9号、吉烟10号、延晒六号3个烟草品种为材料,研究了不同浓度的Cd溶液对烟草种子萌发以及烟苗生长发育的影响。结果表明,Cd胁迫下烟草种子发芽势、发芽率、发芽指数、活力指数、苗高均受到抑制;烟苗叶绿素含量降低,根冠比变小,生长受到抑制,CAT活性、SOD活性、可溶性糖含量随Cd浓度的增加呈先增后降的趋势,POD活性、MDA含量、Pro含量、Cd含量均随Cd浓度的增加而增加。可见Cd胁迫能不同程度地影响烟草种子萌发和烟苗生长发育,烟苗体内的抗氧化酶系统被破坏,多种酶活性不协调,生理生化过程紊乱,最终导致烟苗受害。     

基于qPCR和LAMP技术的马铃薯晚疫病菌快速检测方法

马铃薯晚疫病菌（Phytophthora infestans）能侵染多种茄科植物,它引起的马铃薯晚疫病,是马铃薯生产中的第一大病害。为了开发能在田间快速检测马铃薯晚疫病病原的方法,利用P. infestans T30-4基因组测序数据的contig 1.18131,设计qPCR和LAMP引物,优化扩增条件后得到引物的特异性和灵敏度,最后通过检测田间收获薯块,比较形态学传统方法、qPCR及LAMP的差异。特异性检测结果发现,qPCR和LAMP仅在含有P. infestans DNA模板的体系有阳性扩增,在寄主和其他微生物DNA中均无扩增;在优化的条件下,qPCR和LAMP的检测下限可达1×10 ^-6ng/μL,在有寄主和其他微生物DNA存在的条件下,引物的灵敏度没有显著差异。利用两种快速方法对在大理、丽江及昆明3个地区田间收获薯块上检测发现,qPCR和LAMP方法得到的检出率差异极为不显著（P=0.420）,两种快速检测方法和形态学鉴定方法检出率差异极显著（P=0.009）。在大理、丽江及昆明3个地区的薯块中,两种分子检测方法检出率均比形态学方法高。其中,qPCR检测方法比形态学方法分别提高了12.00%、2.00%、8.70%;LAMP检测方法比形态学方法分别提高了11.30%、2.00%、8.70%。     

喜马拉雅樱花嫩枝扦插影响因子探究

扦插是一种简单并且常用的樱花苗木繁殖方法,喜马拉雅樱花作为一种优秀的樱花种类,关于其扦插繁殖的研究还未见报道。本研究开展了喜马拉雅樱花的嫩枝扦插试验,主要目的是研究栽培基质和同一枝条不同部位的插穗等因子对喜马拉雅樱花生根率、成活率以及新梢生长的影响。研究结果表明:栽培基质对插穗生根、成活和新梢生长影响显著,以细河沙、珍珠岩(1∶1)为栽培基质插穗平均生根率最高为92.0%,以草炭土、珍珠岩(2∶1)为栽培基质插穗成活率最高,可达到85.3%,插穗在草炭土、珍珠岩(3∶1)基质中新梢生长最快,平均长度可达11.5 cm;插穗部位方面,中部插穗平均生根率和平均成活率最高分别可达97.3%和92.7%。本研究对促进喜马拉雅樱花的规模化繁殖,加速该樱花种类在中国的普及应用,具有重要的实践意义。     

棉花叶枝数与种植密度对单株结铃数的影响

为了探明棉花叶枝数和密度对单株结铃的影响规律,试验设置5种留叶枝方式：不留叶枝（CK）、留1叶枝、留2叶枝、留3叶枝、留全部叶枝;5个种植密度（万株·hm^－2）：2.25,3.00,3.75,4.50,5.25。研究结果表明：在同一密度条件下,随叶枝的增多,单株铃数增加;留1叶枝单株铃数较对照增加10%左右,留2、3叶枝单株铃数较对照增加15%左右,保留全部叶枝较对照增加25%左右。在同一叶枝处理下,随密度的增加,单株铃数减少;密度每增加7500株·hm^－2,5种留叶枝方式的单株结铃分别减少2.60个、3.04个、3.06个、3.44个和3.71个。总铃数随叶枝和密度的增加而增加,当总成铃为88.24万个·hm^－2时产量最高。