Development and evaluation of pyramiding lines carrying early or late heading QTLs in the indica rice cultivar ‘IR64’

The heading date is an important trait for determining regional and climatic adaptability in rice. To expand the adaptability of the indica rice cultivar ‘IR64’, we pyramided multiple early or late heading quantitative trait locus (QTLs) in the ‘IR64’ genetic background by crossing previously developed near-isogenic lines (NILs) with a single QTL for early or late heading. The effects of pyramiding QTLs were observed in three different climatic zones of the Philippines, Madagascar, and Japan. The early heading pyramiding lines (PYLs) headed 6.2 to 12.8 days earlier than ‘IR64’ while the late heading PYLs headed 18.8 to 27.1 days later than ‘IR64’. The PYLs tended to produce low grain yield compared to ‘IR64’. The low yield was not improved by combining SPIKE, which is a QTL that increases the number of spikelets per panicle. Conversely, ‘IR64-PYL(7+10)’ carrying Hd5 and Hd1 headed earlier, produced more tillers, and more panicles per m² than ‘IR64’, and mitigated the yield decrease in early heading. These results suggest that the effects of pyramided QTLs on heading date were consistent across various environments and PYLs could be used to enhance the adaptation of ‘IR64’ in other rice growing environments.     

3种含氯消毒剂对柑橘黄龙病菌室内防治效果研究

柑橘黄龙病是柑橘生产上最具毁灭性的病害,目前没有防治特效药也没有较好的抗性品种。本文以含氯消毒剂作为柑橘黄龙病菌防治的候选药剂开展药剂筛选试验。将染病接穗分别浸泡3种含氯消毒剂再嫁接到健康枳壳砧木上,利用定量PCR技术定量分析药剂处理前后黄龙病菌含量的变化,建立柑橘黄龙病菌药剂防治效果评价体系。试验结果表明,漂白粉（CH）不适合利用嫁接技术进行候选药剂筛选;二氯异氰尿酸钠（NaDCC）和三氯泡腾消毒片（TCCA）的抑菌效果随处理浓度的降低而减弱,在有效氯含量为5000mg/L时,病菌减退率最高,分别为99.1%和99.5%,相对防效最佳,分别达到了97.9%和98.8%,与对照药剂盐酸四环素(TET)的抑制效果相当,说明NaDCC和TCCA可以作为柑橘黄龙病化学防治的候选药剂。     

栀子几个主要数量性状的相互关系研究

以孝感市孝南区西河镇的成年栀子林为试材,对栀子的6个数量性状进行了相关分析、通径分析和主成分分析。结果表明:单株果数和单位面积产量,应作为丰产栽培选择的重要性状;树高和冠幅主要是通过单株果数来影响单株产量,在生产中要注意协调好树高、冠幅和单株果数的关系;单果重也可适当考虑。     

Quantitative trait loci analysis for root traits in synthetic hexaploid wheat under drought stress conditions

Synthetic hexaploid wheat(SHW), possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties. We evaluated 10 root traits at seedling stage in 111 F9 recombinant inbred lines derived from a F2 population of a SHW line(SHW-L1) and a common wheat line, under normal(NC) and polyethylene glycol-simulated drought stress conditions(DC). We mapped quantitative trait loci(QTLs) for root traits using an enriched high-density genetic map containing 120 370 single nucleotide polymorphisms(SNPs), 733 diversity arrays technology markers(DArT) and 119 simple sequence repeats(SSRs). With four replicates per treatment, we identified 19 QTLs for root traits under NC and DC, and 12 of them could be consistently detected with three or four replicates. Two novel QTLs for root fresh weight and root diameter under NC explained 9 and 15.7% of the phenotypic variation respectively, and six novel QTLs for root fresh weight, the ratio of root water loss, total root surface area, number of root tips, and number of root forks under DC explained 8.5–14% of the phenotypic variation. Here seven of eight novel QTLs could be consistently detected with more than three replicates. Results provide essential information for fine-mapping QTLs related to drought tolerance that will facilitate breeding drought-tolerant wheat cultivars.     

菠萝酸性转化酶基因家族初步生物信息学及表达分析

酸性转化酶（acid invertase, AIN）在菠萝采后蔗糖降解过程中起着重要作用,基于菠萝全基因组数据库,预测菠萝AIN家族基因并进行生物信息学分析,解析其在采后菠萝不同贮藏温度下的表达变化情况,为阐明AIN基因在采后菠萝果实贮藏特性中的作用奠定基础。以水稻AIN家族基因为探针,在菠萝全基因组中鉴定到2个菠萝细胞壁酸性转化酶基因（cell wall acid invertase, CWIN）和2个液泡酸性转化酶基因（vacuolar acid invertase, VIN）,分别命名为AcCWIN1、AcCWIN2、AcVIN1、AcVIN2,设计编码区引物进行测序验证,并进行生物信息学分析。进化分析结果表明,AcCWIN1、AcCWIN2和AcVIN1、AcVIN2蛋白分别归于细胞壁酸性转化酶和液泡酸性转化酶2个进化支上,且均属于糖基水解酶家族GH32,基因结构、保守域和保守基序均一致。荧光定量分析结果表明,菠萝果肉中AcVIN1和AcVIN2在果实采后贮藏过程中表达量升高,且AcVIN1在发生黑心病的部位大量表达,而AcCWIN1和AcCWIN2在采后贮藏过程中表达量逐渐降低,且随着贮藏温度的升高其表达量降低,预示AcVIN1、AcVIN2较AcCWIN1、AcCWIN2在菠萝采后蔗糖降解和黑心病的发生方面发挥着更为重要的作用。     

不同地区楼葱栽培种的性状与品质分析

为了研究不同地区楼葱的特性,试验对我国不同地区12个楼葱栽培种的数量性状和品质性状进行了测定分析。14个数量性状的相关分析结果显示,主成分分析数量指标后,单株质量、株高、假茎质量、花葶高、叶形指数和假茎指数影响分类;相关性分析说明主要数量指标间具有极显著相关性(P<0.01)。聚类分析后,遗传距离为3.1时可将楼葱种质根据所得主要数量性状分为4个类群。测定不同地区楼葱6个品质指标后,相关性分析结果表明,紧实度与蛋白质含量、干物质率、香辛油含量、总糖含量、游离氨基酸总量存在着极显著正相关或相关性,主成分分析表明主成分反映了89.99%的原有信息量,楼葱的干物质率与紧实度为主要成分;应用灰色关联度分析了品质与数量性状的关系,假茎直径、出叶孔间距、单株质量这3个数量性状对楼葱品质的影响居前3位。研究表明楼葱种质材料具有极其丰富的遗传多样性,宁夏同心2个地区黄水桥HSQ、石羊圈SYJ的楼葱种质距其他种质资源间亲缘关系最远且干物质率含量及紧实度最高。     

花生荚果发育及其调控研究进展

花生是重要的油料与经济作物,在农业种植业结构调整中发挥重要作用。荚果是花生的收获器官,深入 研究花生荚果发育及其调控,可以为高产育种提供理论依据。本文从花生荚果发育过程和内外限制因素的调控作 用,并结合激素、营养元素、遗传学研究以及DNA、RNA等分子调控机制,综述了近年来花生荚果发育相关的研究进 展,为后续研究提供参考。