[目的]明确多样性混合间栽模式对水稻光合作用的影响,为水稻多样性混合间栽的进一步推广应用提供有利依据.[方法]选用水稻品种冈优157和黄壳糯,在多样性混合间栽(包括里行和边行)和净栽2种种植模式下,测定其叶绿素相对含量SPAD值和光合指标值,并调查了穗颈瘟发生为害情况及水稻农艺性状.[结果]多样性混合间栽模式下冈优157里行的SPAD值显著高于其边行以及净栽处理,黄壳糯在2种种植模式下的SPAD值则无显著差异.多样性混合间栽模式下冈优157里行的净光合速率显著低于净栽处理,和边行无显著差异;蒸腾速率、气孔导度和胞间CO2浓度在2种种植模式下均无显著差异;黄壳糯的净光合速率、蒸腾速率、气孔导度和胞间CO2浓度在间栽和净栽模式下均无显著差异.冈优157和黄壳糯在多样性混合间栽和净栽种植模式下的水分利用率均无显著性差异.黄壳糯的稻瘟病病情指数多样性混合间栽模式(2.79±0.86)显著低于净栽(43.65±6.11);其株高在间栽模式(138.93±2.91)cm显著低于净栽(152.07±2.27)cm;而黄壳糯的分蘖数净栽模式(9.75±0.59)显著高于间栽(7.04±0.73).冈优157的病情指数、株高和分蘖数在2种种植模式下均无显著差异.多样性混合间栽模式下黄壳糯的折合产量(6.23 t/hm2)显著高于净栽模式(4.50 t/hm2);冈优157在2种种植模式下的折合产量无显著差异.[结论]多样性混合间栽模式下主栽品种冈优157的叶绿素含量显著升高,光合速率显著降低,其他光合特征值无显著变化,病害发生程度均为轻发生;间栽品种黄壳糯的光合表现在2种模式下无显著差异,而黄壳糯的病害发生程度在多样性间栽模式下显著降低;多样性混合间栽模式下水稻产量显著升高.

为了明确云南省水稻地方品种的稻瘟病抗性、抗瘟基因型组成情况以及产量信息,本研究对云南省五大稻区收集的51份水稻地方品种进行稻瘟病室内抗性鉴定、抗瘟基因型分析、田间抗性评价及产量测定.抗瘟基因型鉴定结果表明,供试的水稻地方品种抗性基因较为丰富,Pii、Pik-s和Pi33个基因型的出现频率最高,占供试品种的52.9％.稻瘟病抗性评价及产量测定结果表明,13.7％的地方品种抗所有供试菌株,传统品种中'冷水谷''粘钰香''毫糯洪''海滨糯''思茅糯'田间与室内抗瘟性评价均为高抗,且产量均在400 kg/667 m2以上,为优质抗性育种材料.本研究为云南省水稻持久抗病品种的选育提供参考.

[目的]分析云南省地方籼稻和粳稻的稻瘟病抗性和农艺性状差异,筛选适宜于种植区环境的优异地方稻种,为稻瘟病的抗性育种及良种选育提供理论依据.[方法]以云南地方籼稻和粳稻品种各23份为材料,利用8个稻瘟病菌株进行室内苗期稻瘟病抗性鉴定及抗瘟基因推导,并结合田间农艺性状测定结果进行综合评价,筛选出优异地方稻种.[结果]抗性频率为0.0％～25.0％、25.1％～50.0％、50.1％～75.0％和75.1％～100.0％的粳稻品种分别有4、5、6和8个,籼稻品种分别有0、4、7和12个.粳稻和籼稻接种8个稻瘟病标准菌株后,籼稻的稻瘟病抗性整体高于粳稻.46个水稻品种的抗瘟基因组成较复杂,其中,能推导出抗瘟基因的品种共17个,其中粳稻品种7个,籼稻品种10个;抗性基因组成复杂的品种(可能含有的抗瘟基因在6个或6个以上)有23份;含有未知抗瘟基因的品种有6个,均为粳稻;Pik、Piz-t、Pib、Pi1、Pi11和Pita-2基因在籼稻中出现的次数高于粳稻,其中Pita-2基因仅存在于籼稻品种吉强糯和天杂58中;Pik-s、Pita、Pi3、Pi12和Pii基因在粳稻中出现的次数高于籼稻,其中Pi12基因仅存在于粳稻品种日本谷和华街中.农艺性状调查测定结果显示,在株高、穂长、结实率和千粒重方面,粳稻品种间的差异明显大于籼稻品种;在产量方面,籼稻品种间的差异小于粳稻品种.筛选出的高抗稻瘟病品种:镰刀谷(粳稻)、香糯(籼稻)、毫糯早(籼稻)和老品种糯谷(籼稻);高产品种:日本谷(粳稻)和粘珏香(籼稻);矮杆品种:冷水汕优(粳稻)和白壳糯(籼稻);多穗品种:日本谷(粳稻)和老品种糯谷(籼稻).[结论]籼稻所含的抗瘟基因数量和稻瘟病抗性整体较粳稻高,说明籼稻的抗谱范围更广.筛选出的粳稻品种冷水汕优和日本谷可用于优质高产品种选育,籼稻品种香糯和毫糯早可用于稻瘟病抗性品种选育.

[目的]评价CdC12溶液对展颖野生稻Oryza glumaepatula单片段代换系(SSSLs)种子发芽及根芽生长的影响,筛选耐Cd SSSLs材料,初步鉴定与芽期耐Cd性状相关的QTLs.[方法]对6个栽培稻品种在0、30、50、100、500μmol·L-1 CdC12溶液条件下进行发芽试验,确定水稻种子芽期耐Cd性研究的处理浓度,筛选耐Cd SSSLs的性状指标.对SSSLs在CdCl2溶液处理下发芽第7天的根长与芽长分析,筛选P=0.01水平耐Cd性较强的SSSLs,鉴定相应性状QTLs.[结果]在0、30、50和100 μmol·L-1 CdC12浓度处理下,栽培稻品种的种子发芽率为91％～95％,差异不显著,但种子根和幼芽伸长生长受到抑制,品种间差异显著.在50和100μmol·L-1 CdC12溶液条件下,以发芽第7天的相对根长和相对芽长为指标,在P=0.01水平从8个SSSLs鉴定出5个相对根长QTLs,即qRRL1-1、qRRL2-1、qRRL3-1、qRRL3-2及qRRL6-1,其加性效应为0.19～0.60,表型贡献率为31.18％～100.59％;鉴定出5份SSSLs携带3个相对芽长QTLs,即qRSL1-1、qRSL1-2及qRSL2-1,其加性效应为0.08～0.18,表型贡献率为7.43％～18.95％.[结论]展颖野生稻SSSLs携带芽期耐Cd QTLs,可以作为水稻耐Cd基因发掘的重要材料.

5-烯醇式丙酮酰莽草酸-3磷酸合酶(5-enolpyruvylshikimate-3-phosphate synthase,EPSPS)是植物体莽草酸途径中除草剂草甘膦的靶标酶.本研究利用过量表达EPSPS转基因栽培稻×杂草稻杂种后代(WH1)进行转录组测序研究,发现水杨酸信号转导途径发生显著富集;稻瘟病抗病性鉴定实验结果表明,过量表达PSPS转基因栽培稻×杂草稻杂种阳性后代(WH1+)与阴性后代(WH1-)的稻瘟病抗病性没有显著差异;代谢物含量检测表明,转基因阳性植株与阴性植株的水杨酸含量基本一致.由此可见,过量表达PSP转基因事件不会通过改变水杨酸水平来影响栽培稻×杂草稻杂种后代植株的稻瘟病抗病性.

[目的]评价水稻多基因型种群品种在云南不同稻区的抗病性和丰产性,为水稻多基因型种群品种在云南的推广应用提供科学依据.[方法]选用3个水稻多基因型种群品种(多集新6号、南八糯和尤群1号)在云南4个不同生态稻区(德宏、文山、红河和楚雄)开展田间抗病和稳产试验,以云南主栽优质高产品种红优7号为对照;选用3个水稻多基因型种群品种(多集新6号、南八糯和尤群1号)和4个云南主栽水稻品种(红优7号、宜香优2115、云粳29号和凤稻23)进行室内抗瘟性评价及抗瘟基因型鉴定,以丽江新团黑谷为感病对照.[结果]田间病害调查结果表明,南八糯在文山稻区、尤群1号在德宏稻区、多集新6号在文山稻区的穗颈瘟病情指数分别为5.73、9.80和8.33,均为中等发生,在其余稻区均为轻发生或不发生;尤群1号和多集新6号在楚雄稻区的稻曲病病情指数分别为10.21和10.60,为偏重发生,在文山稻区的白叶枯病情指数分别为7.20和5.52,为中等发生,在其他稻区均为轻发生或不发生.农艺性状调查结果表明,3个水稻多基因型种群品种的全生育期为137～178 d;株高变异系数(3.10％～6.91％)较低,群体整齐度较好.产量测定结果表明,多基因种群品种在红河(籼粳混栽区)和德宏(籼稻区)的产量高于或显著(P<0.05)高于文山(籼稻区)和楚雄(粳稻区);与对照品种相比,多基因型种群品种的产量高于对照或与对照相当.室内抗瘟性评价及抗瘟基因型鉴定结果表明,多基因型种群品种与云南主栽品种相比含有较多的主效抗性基因.[结论]水稻多基因型种群品种对稻瘟病、白叶枯病和稻曲病的抗性较好,农艺性状一致,具有一定的丰产潜力,在云南具有良好的适应性和稳定性.

为了明确不同地理位置杂草稻群体的遗传多样性现状、遗传分化水平以及杂草稻群体之间的基因流.本研究利用24对SSR引物对来自黑龙江、吉林、辽宁、江苏和广东共17个杂草稻群体的469份杂草稻样本进行的遗传多样性及遗传分化分析.结果表明杂草稻群体的总体遗传多样性较为丰富(I=0.36,He=0.23),不同杂草稻群体间的遗传多样性指数差异较大,He在0.07～0.35之间.AMOVA分析结果表明,杂草稻群体70％的变异来源于群体间,30％的变异来源于群体内.聚类分析显示,相邻地区的种群间相似性较高,江苏省杂草稻的不同种群间存在较高遗传分化;遗传分化与基因流结果表明,17个杂草稻种群间总的Nm值为0.117,总Fst值为0.694.地理位置较近的种群间Nm普遍较高,Fst较低;而地理位置较远的种群间Nm普遍较低,Fst较高.总之,本实验中的杂草稻群体总体的遗传多样性水平较高,群体之间的遗传多样性指数差异较大;杂草稻群体间的遗传分化显著大于群体内的分化,符合遗传距离的空间隔离模型;杂草稻群体间和地区间有一定水平的基因流,本研究对理解杂草稻在农田生态系统中的适应性进化及制定杂草稻控制策略具有重要意义.

选育抗病品种是防治稻瘟病的有效措施,通过对主栽水稻品种的抗稻瘟病基因型鉴定,以期筛选出新的抗病良种.本研究通过喷雾接种的方法,用已知抗瘟基因型的9个稻瘟病菌株,对云南省56个主栽水稻品种进行了抗瘟基因型鉴定和分析.结果表明56个水稻品种可能含有1个或多个抗瘟基因,其中Pita-2、Pi5、Pi9、Piz-t4个基因出现频率较高,可以推测这4个基因对云南省水稻抗瘟性尤为重要,Pi5、Pi9这两个基因都可在粳稻区和籼稻区使用;携带Pi20基因的粳稻品种对稻瘟病菌菌株抗性频率均大于70％,Pi20基因可作为粳稻区的有效抗源.云南主栽水稻品种的抗瘟基因型分析表明,绝大部分水稻品种对稻瘟病的抗性良好,对于推广年限长的水稻品种要及时进行提纯复壮,防止品种抗病性退化;还需发掘和丰富抗病育种的抗源,防止抗性基因失效.

“大学生创新创业训练计划”(以下简称“大创计划”)项目是人才培养模式的创新,其中一系列项目的实施,体现了华南农业大学生命科学学院在人才培养方面的重要举措.华南农业大学生命科学学院不断深化教学改革,建立了具有特色的“大创计划”项目实践教学新模式,积极引导大学生参与.目前,从四个方面体现了实施“大创计划”项目实践教学改革的举措和成效,促进大学生创新创业素质的培养和能力的提升,取得了较好的效果.

Aiming to analysis the characteristics of DNA methylation during the development processes of leaf and spikelet to explore the effect of genome shock in different tissues of hybrid F1 between O.sativa and O.officinalis,moreover,the possibility of biological effects,in this study,using the methylation sensitive amplified polymorphism technology (MSAP),patterns and levels of global genomic DNA methylation in leaf and spikelet from parents to interspecific hybrid F1 were investigated.The results showed that,the similar change trends of DNA methylation level in tissues of leaf and spikelet were observed in all the experimental materials,that is,along with the plant growth and development the DNA methylation level was on a downward trend,and the full methylation level was significantly higher than hemi-methylation level in both leaf and spikelet(P=0.000).In hybrid leaf tissue at the tillering stage, meiosis stage of pollen mother cells and flowering stage,the average total methylation level,full methylation level and hemi-methylation level was 20.19%,16.06% and 4.13%,respectively,which was higher than that of the two parents;while in hybrid spikelet tissue at the meiosis stage of pollen mother cells, microspore development stage and matured pollen grain stage,the average level of total,full and hemi-methylation was 17.38%,13.67% and 3.71%,respectively,which was higher than that of Liaojing 944 and lower than O.officinalis.However,only hemi-methylation level of hybrid was significantly higher than Liaojing 944(P=0.015).DNA methylation patterns in leaf and spikelet were very similar in parents and hybrid.Sequence analysis of 94 differentially methylated fragments showed that 38 fragments were sequence similarity in the NCBI database.The results would be helpful for further analysis of hybrid sterility between O.sativa and O.officinalis.

[目的]敲除鱼腥藻PCC 7120的alr0267基因,并对其功能进行初步研究.[方法]克隆获得鱼腥藻PCC 7120 alr0267基因部分片段,通过构建敲除载体,使其与目的基因发生单交换同源重组,从而将鱼腥藻PCC 7120中的alr0267基因敲除,并对敲除体进行纯化和PCR鉴定,然后对alr0267敲除体和野生型固氮异形胞进行形态观察和统计,同时采用实时荧光定量PCR,在培养不同时间(0,3,8,24 h和10d)检测野生型和alr0267基因敲除体中与异形胞功能相关基因all0813、all2736、alr2887的相对表达量.[结果]鱼腥藻PCC 7120 alr0267基因被成功敲除;在缺氮条件下培养6～12 d,敲除体异形胞营养细胞数的均值明显少于野生型;实时定量PCR分析表明,野生型中all0813、all2736、alr2887基因表达量均在培养24 h达到最大,敲除体中这3个基因最大相对表达量的出现时间均有所延迟.[结论]alr0267基因敲除导致异形胞分化频率增加,同时影响异形胞的正常发育.

采用模糊隶属函数和系统聚类的分析方法,研究抗旱处理期间,宿根甘蔗叶片的衰老情况以及质膜透性、脯氨酸、可溶性糖、丙二醛、水分含量、叶绿素、净光合速率(Pn)、胞间CO2浓度(Ci)、气孔导度(Gs)、蒸腾速率(Tr)、水分利用率(WUE)等生理生化指标对干旱胁迫的响应.结果表明:结合各种生理生化指标的模糊隶属函数值,利用系统聚类将8个甘蔗品种宿根时的抗旱性划分为3类;其中,新台糖10、粤糖93-159、新台糖22、桂糖11、闽糖69-421表现出较强的抗旱性,粤糖86-368表现出中度抗旱性,滇蔗01-58和崖城89-9表现出较弱的抗旱性,所得结果与形态指标基本一致.利用隶属函数和聚类分析进行宿根甘蔗抗旱性的综合评价,可避免单一指标的片面性和不稳定性,适用多品种之间的比较.

This research established a reference transcriptome of sugarcane which consists of three sugarcane parents and eight sugarcane cultivars/lines from different sources based on RNA-Seq technology. By related bioinformatics analysis, the results showed that 98 945 contigs were obtained through sequencing the mixed samples of sugarcane+1 leaf by transcriptome sequencing. There are 5 806 SSR loci were found in 98 945 contigs. The characteristic of SSR distribution showed that tri-nucleotide repeat was the highest, and the lowest was hexanucleotide repeat. The types of SSR were analyzed that CCG/CGG was the highest repeat. By further processing of contigs, 75 656 unigenes were obtained, for which 53 951 unigenes had been annotated through blasting with Nr database, Swiss-Prot database, KEGG database and the COG database. Base on results of Nr and KEGG annotation, 44 functional groups and 123 pathways were obtained through GO and KEGG functional classification. These results laid the foundation for studying the gene's expression of sugarcane at spatial and temporal difference.

Drought is a kind of abiotic stress, which seriously affect crop yield. Sugarcane is an important economy and energy crop, but there is little knowledge about drought-response mechanism in sugarcane. In this study, high throughput sequencing is employed to research the drought response process in sugarcane cultivar ROC22 and there are 6 861 up-regulated and 4 574 down-regulated genes found. At the same time, we discovered some genes involved with water or oxidative stress response. Many transcription factors and protein kinases are discovered too. Finally we verified our sequencing results by real-time quantitative PCR.

In this study, a new drought related NAC family gene was cloned from India Saccharum Spontaneum named ScNA C1 (NCBI accession KP742345). This gene contained 1 212 bp open reading frame, coding 403 amino acids; Homologous gene alignment results showed conserved NAC domain in N terminal of ScNA C1, and phylogenetic tree analysis showed it belonged to NAP subfamily of NAC family. Arabidopsis protoplast transformation of ScNAC1-GFP fused vector demonstrated ScNA C1 subcellular located in nuclear. Real time quantitative PCR results shown ScNAC1 can be induced by drought in any developmental stage of Saccharum Spontaneum. This study laid foundation for deep understanding of drought-response mechanism of sugarcane.

研究6个云南甘蔗主栽品种新台糖22号、闽糖69-421、桂糖11号、粤糖86-368、粤糖93-159、滇蔗01-58对干旱胁迫的响应差异.采用大棚盆栽和人工控水的方法对6个处于伸长期的甘蔗品种进行干旱胁迫,处理期间调查供试品种株高、茎径、有效茎等形态指标,测定脯氨酸含量、可溶性糖含量、叶绿素含量、净光合速率、气孔导度、蒸腾速率等生理指标.结果表明:综合各种生理指标的模糊隶属函数评价法和系统聚类分析法,是一种较科学的抗性鉴定方法,适用于多个品种之间的比较;生理指标结合形态指标来看,抗旱性最好的品种是新台糖22号和粤糖86-368,适合在云南干旱地区种植.

为研究云南6个甘蔗品种苗期对干旱胁迫的响应,确定各品种的抗旱性,采用盆栽试验的方法,在人工控水造成干旱胁迫的条件下,测定可溶性糖含量、游离脯氨酸含量、叶绿素含量、丙二醛含量、水分含量和质膜透性等生理指标.采用模糊隶属函数、系统聚类法对多指标进行综合分析,全面评价6个甘蔗品种的抗旱性.结果表明:‘闽糖69-421’表现出较强的抗旱性,‘新台糖22’和‘桂糖11’表现为中度抗旱性,‘粤糖86-368’、‘滇蔗01-58’、‘粤糖93-159’表现出较弱的抗旱性.

Objective: The strong electric field radiation under atmospheric pressure to the rice 6 the influence of DNA methyla-tion.Methods: Under atmospheric pressure at the same time,based on the different strength(and in the same strength,in different time) radiation Guodao 6 seed,the application of DNA methylation sensitive amplification polymorphism(methylation sensitive amplification polymorphism,MSAP) technology,the research in different radiation condition,the rice genome DNA methylation level and difference.Results: All the strong electric field radiation treatment group methylation level than the control group did not radiation reduced,and ra-diation time and strength about.All cell DNA methylation,half methylation amplification sites accounted for the proportion of amplifica-tion sites for: 12.89% ~ 13.62%,3.36% ~ 4.63%,with the increase of radiation intensity and time reduced.Conclusions: The strong elec-tric field radiation kingdom rice 6 rice genome DNA methylation is parent changed obviously variation that strong electric field can cause apparent genetic variation,and the rules for the research laid the foundation for discussion,and rice methylation on rice growth control molecular mechanism provides the help.

In order to explore the cold tolerance characteristics of rice new male sterile lines and its physiological and biochemical mechanism,the study focused on the identification of cold tolerance and determination of MDA contents,peroxidase activity,and biomass contents at seedling stage through light incubator culture and the normal methods for determination of malondialdehyde (MDA) content,peroxidase activity,and biomass contents,by using a set of male sterile lines which were with the same cytoplasm derivation and different nucleus derivations and another set of male sterile lines which were with the same nucleus derivation and different cytoplasm derivations.The results showed that,the cold tolerance was classified to 4 types,G huaxiang 2A was most tolerant to cold stress (the first class),whereas Y ruanxiang A was the weakest one for cold tolerance (the ninth class).By comparing the cold tolerance level of the male sterile lines with the same cytoplasm derivation and different nucleus derivations,G huaxiang 2A was the most tolerant,G huaxiang 1A was the second,and G ruanxiang A was the third.It showed that nuclei gene affects the cold tolerance of the sterile lines.By comparing the cold tolerance level of the male sterile lines with the same nuclei derivation and different cytoplasm derivations,WA ruanxiang A was the most tolerant,G ruanxiang A was the second,and Y ruanxiang A was the third.It showed that cytoplasm gene affects the cold tolerance of the sterile lines.The content of MDA,the activity of POD,and the seedling height,number of seedling roots and fresh weight were all related to the cold tolerance of the sterile lines.That is,if a sterile line was more tolerant to cold stress,its relative MDA content was lower,its relative POD activity also was lower,its relative fresh weight of biomass was higher.

In order to approach the effects and action mechanism of dimethyl sulfoxide(DMSO) and tetrahydrofuran(THF) on pepsin,the catalytic activity,kinetics parameters,ultraviolet absorption spectra,ultraviolet differential spectra,and fluorescence emission spectra of pepsin were investigated.It was indicated that pepsin activity was enhanced by 83.4% as the enzyme was treated with 9%DMSO.But when pepsin was treated with 1%THF the enzyme activity was enhanced only by 3.59%.In hydrochloric acid solution the kinetics parameter of the enzyme, K m=2.22 mg/mL,v max=1.1×106 U/mg Pro.In 9%DMSO, K m=1.50 mg/mL,v max=0.5×106 U/mg Pro.In 1%THF,K m=1.91 mg/mL and v max=0.51×106 U/mg Pro.In 9%DMSO the ultraviolet absorption of pepsin peptide bonds was strongly inhibited.But the ultraviolet absorption of aromatic amino acids of pepsin was not inhibited.The ultraviolet absorption of pepsin molecules was not influenced obviously in 1%THF.Both in 9%DMSO and in 1%THF the ultraviolet differential spectra of pepsin showed obvious positive and negative peaks.The fluorescence emission peak of pepsin enzyme moved to short wavelength direction by 1 nm in 9%DMSO.But in 1% THF the fluorescence emission spectrum did not change obviously.It was concluded from these results that the conformation of pepsin molecules changed obviously in both 9%DMSO and 1%THF.This led the K m value of the enzyme descended and the affinity of the enzyme to substrates enhanced.So the catalysis activities of the enzyme were increased in some extent in these solutions.