稻田水旱轮作是解决水稻连作障碍的有效途径,同时有利于提高稻田产出效益及耕地利用率,对促进贵州地区水稻种植提质增效和推进农业产业结构调整具有积极意义.为贵州深入推广稻田水旱轮作模式提供参考,综述贵州山区稻田水旱轮作模式在水稻产量、氮肥利用率、土壤理化特性方面的生态效应研究,介绍目前贵州山区常见的稻田水旱轮作模式,从加强不同作物生长发育特征特性研究、强化科技支撑与技术服务、因地制宜选择轮作模式方面提出贵州山区稻田水旱轮作模式的发展建议.

Leaf-color mutants are ideal genetic materials for studying the mechanism of chlorophyll (Chl) biosynthesis and chloroplast development. Here we isolated and identified a novel rice yellow-green-leaf mutant from a 60Co-irradiated mutant pool, named ygl219. In the ygl219 mutant, the pigments contents were decreased and the development of chloroplast was arrested. Map-based cloning and subsequent DNA sequencing analysis revealed a single nucleotide substitution happened in divinyl reductase (DVR) gene in the ygl219 mutant. Genetic complementation of the ygl219 mutant restored normal green leaf by expressing full length coding sequence of DVR. Subcellular localization indicated the DVR protein was located in the chloroplast. qRT-PCR analysis revealed that most of the genes associated with chlorophyll biosynthesis were significantly upregulated, while most of the genes associated with chloroplast development and photosynthesis were significantly downregulated in the ygl219 mutant. These data indicated that DVR plays an important role in chlorophyll biosynthesis and chloroplast development in rice.

Abstract Background Japonica rice (Oryza sativa L.) is a subspecies of the Asian cultivated rice and is popular because of its better quality. The genetic diversity of japonica rice germplasm resources is the basis for japonica variety breeding and improvement. Genetic diversity is evaluated by means of phenotypic identification and molecular markers. Molecular markers are more stable and less susceptible to interference by environmental factors, whereas phenotypes are susceptible to environmental factors. In this study, 150 japonica rice varieties from different ecological zones were used to analyze their kinship and population structure by next-generation sequencing technology. The phenotypic diversity was then evaluated using ten agronomic traits under two different environmental conditions, Guiyang and Hainan, respectively, and the effect of different environmental conditions on the phenotypic diversity evaluation was analyzed. The present study will provide a comprehensive assessment of the genetic diversity of japonica rice varieties from different ecological zones and provide a theoretical foundation for parental selection in conventional japonica rice breeding. Result The results of sequencing and population structure analysis showed that the 150 japonica varieties were abundant in genetic variation, without homogeneity and subgroup differentiation. The identification of phenotypic diversity also showed that the phenotypes of these japonica rice varieties from different ecological zones are rich in diversity under different environmental conditions. In addition, different environments had a significant impact on the results of phenotypic diversity evaluation such as diversity index, enrichment intervals, agronomic trait correlations, and composite scores based on regression analysis for japonica rice varieties from different ecological zones. In Guiyang, the top 10 overall agronomic traits were Yungingnuo (JR_LN38), Chugeng37 (JR_LN32), Chugeng28 (JR_LN34), Fuhedao255 (JR_LN50), Guangminggeng2Hao (JR_LN96), Chugeng7 (JR_LN39), Chugeng40 (JR_LN33), Liaogeng401 (JR_LN102), Bigeng44 (JR_LN107), Sugeng45 (JR_LN76), however, in Hainan, the top 10 in terms of overall performance were, respectively, Chugeng7 (JR_LN39), Lemont (JR_LN149), Chugeng32 (JR_LN43), Chugeng28 (JR_LN34), Bidao126 (JR_LN105), Tenggeng2 (JR_LN45), Chugeng26 (JR_LN41), Tengxi138 (JR_LN153), Hexi27-2 (JR_LN145), Chugeng39 (JR_LN44). Conclusion 150 Japonica rice varieties from different ecological zones are abundantly genetically diverse, with no homogeneity and no subpopulation differentiation that can be utilized as parental resources for Japonica rice variety breeding. In conventional breeding, breeders often rely on phenotypes as an important basis for parental selection. Given that different environments have a strong influence on the evaluation of phenotypic diversity of japonica rice germplasm resources, it is necessary to conduct a comprehensive evaluation of germplasm resources based on a large amount of agronomic trait data obtained in the local environment to screen for desirable parents after the breeding target has been determined.

Floret opening and closure are critical for rice to complete reproductive development. To further understand the molecular mechanism of floret opening and closure in rice, RNA-seq was performed on the floret of Indica and Japonica rice in the state of 1-h before floret opening, at the opening and closure, respectively. Our results show that many differentially expressed genes are produced throughout the floret opening and closure of both Indica and Japonica rice. Differentially expressed genes shared between Indica and Japonica rice at floret opening were involved in seven metabolic pathways, including plant hormone signal transduction, MAPK signaling pathway-plant, starch and sucrose metabolism, alpha-Linolenic acid metabolism, plant–pathogen interaction, diterpenoid biosynthesis, glucuronate interconversions, phenylpropanoid biosynthesis, compared to 1 h before floret opening. In addition, the expression patterns of some genes, OsJAZ13, OsJAZ11 and OsCML1 which the above metabolic pathways, were different between Indica and Japonica rice. Compared to the floret opening, the differentially expressed genes at floret closure were mainly involved in the following three metabolic pathways: Circadian rhythm-plant, sesquiterpenoid and triterpenoid biosynthesis, starch and sucrose metabolism, and thiamine metabolism. This study provides insights into revealing the molecular mechanism of floret opening and closure in rice.

Rice is an important staple crop, and fertilization has a very important role in the production of high-yield and well-quality hybrid of rice. The abnormal development of female gametes will lead to a significant decrease in rice yields. Due to the complex mechanism of female gamete development, the molecular mechanism of female sterility has not made a breakthrough. In this study, one semi-sterile mutant m21 and its fifth generation of backcross material (WZN58 and WZN68) were used as materials, and the phenotypic observation and cytological observation of embryo sac development were performed. Moreover, the pollen viability was evaluated by iodine potassium iodide (I2-KI) staining. Bulked-segregant analysis (BSA) re-sequencing and transgenic analysis were further applied to investigate the molecular mechanism of semi-sterile phenotype. These results demonstrated that male gamete development was normal, while the abnormality of the mutant was caused by the abnormal development of female gamete. Among 112 candidate genes detected by BSA, one gene Os10g0506000 was identified responsible for the semi-sterile phenotype of m21 mutant. This study provides an ideal material and candidate gene for rice female fertility analysis.

优质稻米大粒香是采用粳籼杂交方法育成的香稻品系,多年来是贵州省优质稻米企业开发生产的主推品种.但稻瘟病抗性差,限制了其大规模推广应用.本研究以大粒香为材料,根据CRISPR/Cas 9靶点设计要求设计稻瘟病基因pid3特异性靶点sgRNA序列,构建crispr-pid3双靶点载体,通过农杆菌介导遗传转化大粒香愈伤组织,获得45株转基因苗,有30株阳性苗.在T1代中共获得9株无Cas 9转基因位点的pid3纯合突变体,对其进行稻瘟病病情鉴定,与原种大粒香相比,稻瘟病抗性均有一定程度提高.且对改良株系进行米质鉴定,与野生型大粒香相比,稻米品质并未发生显著改变.说明改良株系的米质并未因pid3基因的编辑而受到影响.

稻瘟病是危害水稻生产的主要病害,分子标记辅助选择(MAS)已经成为选育抗病品种的重要方法.本研究以含有广谱抗性基因pi9的DW808为供体亲本,导入区域适应性好的受体亲本R894;经过分子标记检测、田间自然鉴定、人工接种鉴定,选育出中抗稻瘟病的恢复系黔恢101;其组合安优101于2017年参加贵州省水稻区域试验,2019年通过贵州省审定.

为探讨贵州禾苟当1号在从江地区栽培的最佳条件,以贵州禾苟当1号为研究对象,在从江县海拔633 m和840 m开展大田试验,分别在不同种植密度下(处理1,6225穴/667m2;处理2,7559穴/667m2;处理3,8893穴/667m2;处理4,10227穴/667m2和处理5,11561穴/667m2)进行种植,研究苟当1号在不同海拔及不同密度下的农艺性状及产量变化.结果表明:不同海拔下均以密度8893穴/667m2处理的产量最高,海拔633 m和840 m下的最高产量分别为406.97 kg/667m2和478.20 kg/667m2,以密度为6225穴/667m2处理的产量最低,海拔633 m和840 m下的最低产量分别为365.63 kg/667m2和410.97 kg/667m2,即海拔633 m和840 m下最高产量比最低产量分别高16.4％和11.3％;在同一密度下,苟当1号在海拔633 m种植时千粒重、有效穗及产量均高于海拔840 m,但生育期短于海拔840 m.苟当1号在从江地区栽培的最佳密度为8893穴/667m2,最佳海拔为663 m.

In this study, 12 rice varieties were selected to prepare the parboiled rice under the same process conditions. The change trend of quality characteristics and gelatinization properties of parboiled rice before and after preparation were comprehensively evaluated and analyzed. The results showed that the milling quality in the parboiled rice of ‘Yuzhenxiang’, ‘Tianfeng B’, ‘SN16-236’, ‘Guifengyou 785’, ‘Liangyou68’, ‘Huiliangyou 1898’ were better than that before preparation. Because of the yellow grain of parboiled rice of ‘SN16-236’, ‘Liangyou68’, ‘Huiliangyou 1898’ were relatively higher than the raw rice (P < 0.05), which seriously affected the appearance quality of parboiled rice. It was also found that parboiled rice could improve the nutrition and the thermal stability of rice paste. In addition, the results of taste quality analysis showed that the appearance and taste values of parboiled rice of ‘Yuzhenxiang’, ‘Hongxiang Rice’, ‘Jinyuanxiang 98’, ‘SN16-236’, ‘15L-Z156’, ‘Guifengyou 785’ were all higher than those before preparation. Based on the above results, the quality in the parboiled rice of ‘Yuzhenxiang’, ‘Guifengyou 785’ were better and suitable for use as special rice varieties of parboiled rice, but the quality of ‘Dalixiang’ and ‘Yuefeng B’ were relatively poor and were not suitable for the production of parboiled rice. This study would provide the theoretical basis for the quality evaluation of parboiled rice and the development and application of rice products.

以近几年贵州省审定的13个优质籼稻米品种(系)为评定对象,利用GC-MS气质联用等仪器进行风味物质、营养成分、质构特性、感官特性等指标的测定.对质构特性数据进行显著性方差分析发现,不同籼稻米的食味值与直链淀粉含量呈极显著负相关(P<0.01),蛋白质含量及垩白度与食味值呈显著负相关(P<0.05),硬度、内聚性、弹性、胶黏性、咀嚼性均与直链淀粉含量呈极显著正相关(P<0.01).风味物质测定结果表明,在13个品种(系)中仅有内6优138、冈香199含有典型稻香成分2-乙酰-1-吡咯啉,在蒸煮过程中具有较明显的香味.营养成分及感官特性结果表明,花香优1618、内6优138和六优385等3种稻米的碱消值分别为5.80、6.20、5.50,耐储性好,直链淀粉含量分别为18.50％、15.30％、15.30％,垩白度分别为5.00％、2.60％、6.80％,感官综合评分较高,宜用作食用大米;而I优4761、冈香199、贵丰优785垩白度分别为16.40％、13.00％、12.90％,直链淀粉含量分别为23.10％、19.00％、23.80％,感官综合评分较低,不宜用作食用大米.

为探索烘干法替代液氮冷冻法研磨水稻叶片提取DNA的可行性,首先比较50℃低温烘干法与液氮冷冻法研磨水稻叶片提取DNA的扩增效果,然后进一步分析不同温度(50、60、70、80、90℃)烘干水稻叶片研磨提取DNA的扩增效果,筛选最佳的烘干温度.结果 表明,水稻叶片在50～ 70 ℃下烘干磨碎所提取的DNA均能进行有效扩增,以50℃效果最佳,其与液氮冷冻法研磨叶片提取DNA的扩增效果无明显差异.水稻叶片烘干法具有操作简单、费用低廉及实用性强等诸多优点,在DNA大量提取中可较好地替代液氮冷冻法对叶片进行制备,具有一定的推广应用价值.

籼稻和粳稻在苗期耐低温基因COLD1的第4外显子存在1个功能性单碱基变异SNP2,粳型COLD1Jap等位基因低温耐受性表现更强,具有重要的育种利用价值.通过籼粳杂交,可将粳型COLD1Jap等位基因导入籼稻品种,提高其低温耐受力.为提高COLD1基因的选择效率,根据粳型COLD1Jap与籼型COLDlInd基因存在的单核苷酸差异,结合扩增受阻突变体系PCR的技术原理设计功能标记.应用5个籼稻品种、5个粳稻品种、1个籼粳杂交F1个体以及1个籼粳杂交F2群体对功能标记进行检测验证.结果 表明,所设计的功能标记可准确区分纯合粳型COLDlJap、纯合籼型COLD1Ind和杂合基因型,其扩增带型与基因型完全一致,是一种鉴定COLD1基因的有效方法.该标记弥补了前人设计的衍生型酶切扩增多态性序列功能标记费用昂贵、操作复杂及费工费时等不足,可广泛应用于水稻COLD1基因的资源鉴定和分子标记辅助选择育种.

Chengyou 33, a new rice variety with heavy panicle (single panicle weight=5.05 g), was bred from the combination between Chengfeng A (an introduced sterile line) and Qianhui 33 (a restorer line) by Rice Research Institute, Guizhou Academy of Agricultural Sciences to promote replace of old and new varieties in rice production in Guizhou and meet the demand of rice varieties with heavy panicle in Southwest rice-growing area with special habitats.The average yield of Chengyou 33 is 660.93 kg/667 m2 in regional test in 2016 and 2017, 3.84％ higher than F You 498 (CK) and the rate of test sites with yield increase is up to 80.0％.The yield of Chengyou 33 is 567.2 kg/667 m2 in production test in 2017, 2.54％higher than F You 498 (CK) and the rate of test sites with yield increase is up to 66.7％.Chengyou 33 approved by Guizhou Crops Variety Approval Committee in 2018 can be planted in rice-growing areas with intermediate and lower altitude in Guizhou.

黔恢35是贵州省水稻研究所采用当地强恢复系R 785和重穗型恢复系R 894杂交选育而成的重穗型水稻新恢复系,具有穗粒数多 、千粒重高 、恢复力强 、配合力高 、植株壮实 、花粉量大 、花粉活力强 、制种产量高等特性;利用自育抗稻瘟病不育系黔79 A与重穗型黔恢35所配组合黔优35经过2年区试及生产试验,于2018年4月通过贵州省农作物品种审定委员会审定.

为解析稻米外观品质遗传基础,挖掘稳定存在的控制稻米外观品质性状的QTL,本研究以籼稻品种V20B和爪哇稻品种CPSLO17作为亲本,构建包含150个重组自交家系(recombinantion inbred line,RIL)的RIL作图群体,进行外观品质性状QTL定位分析.利用特定位点扩增长度测序(SLAF-seq)技术,构建了一个由12个连锁群包含8602个标记,平均间距为0.29 cM的高密度遗传图谱.采用IciMapping 4.0软件的ICIM-ADD方法在3种环境(贵阳、贵定、三亚)对4个外观品质性状(粒长、粒宽、垩白度和垩白粒率)进行QTL (quantitative trait locus)定位分析.结果表明:3种环境共检测到9个粒长QTL、6个粒宽QTL、3个垩白度QTL和4个垩白粒率QTL;有5个QTL在多个环境被重复检测到,其中3种环境都定位到的粒宽QTL qGW5-1和垩白度QTL qCha5-1为同一定位区间(第5染色体的Marker 1642127-Marker 1514505);此外,垩白度QTL qCha5-2的定位区间(Marker 1554573-Marker 1554589)和垩白粒率QTL qCGP5-2也是一样的.序列比对发现QTL qCha5-1定位区间仅51.5 kb,是新的垩白性状主效QTL.本研究结果不仅为挖掘新的外观品质性状基因奠定基础,也有助于开发新的分子标记进行水稻外观品质性状遗传改良.

Dysfunction of OsBADH2 gene in rice is the internal cause of rice to have fragrance. This study applied physicochemical methods to identify the fragrance traits of 7 Guizhou HE ( Oryza sativa ) and 2 control varieties. It was found that RongHe and 2 control varieties were fragrant rice, and the other 6 varieties were all non-fragrant rice. To analyze the internal relationship between fragrant production in Guizhou HE and OsBADH2 gene, the study obtained the CDS sequences of OsBADH2 gene in 9 tested materials, and conducted alignment analysis of these sequences by Megalign software through TA-cloning, sequencing analysis and sequence assembly. The results showed that the OsBADH2 gene CDS of 4 Guizhou HE (BaixiangHe 2, BanpoHe, LipingHe 1 and LipingHe 2) were normal. The CDS differences of RongHe and 2 control varieties were both 8 bp deletion and 3 SNPs in exon 7, and 2 new CDS differences were found among which BaixiangHe 1 was 1 bp deletion and 1 SNP, and BianHe was 2 bp deletion and 2 SNPs. These results might provide the theoretical basis for variety protection and breeding improvement of Guizhou HE ( Oryza sativa ).

The development of female directly affects the fertility office (Oryza sativa).The molecular and cellular mechanisms regulating female fertility in rice remain poorly understood as for it's a complex network.In this study,we identified a new stable genetic female semi-sterility mutant M21.Cytological studies showed the reduced spikelet fertility primarily caused by reduced embryo sac viability.A genetic linkage map covering 2 674.2 cM was constructed based on genome-wide analysis using a backcross population of M21//M21/N22,the genetic map contained 189 SSR makers with an average interval of 14.1 cM;a loci on chromosome 11 between makers RM26761 and RM26841 conferring the female semi-sterility was detected,named qPS-a,which explained more than 20％ of the phenotypic variation for female semi-sterility.No sterility related QTLs/genes were reported between these two markers.These results would be beneficial to the further study on the genetic mechanisms of female semi-sterility in Rice.

该研究以高垩白度品种V20B和低垩白度品种CPSLOi7作为亲本,构建150个V20B/CPSLO 17重组自交家系(RIL)为作图群体,进行稻米垩白QTL检测及其遗传效应分析.以垩白度作为衡量稻米垩白高低的表型数据,结合SLAF标签构建的分子连锁图谱,运用MapQTL5软件检测到4个稻米垩白QTL,分别命名为qC-5a、qC-5b、qC-5c和qC-5d.分析结果表明这4个QTL的LOD值分别为4.02、4.09、3.94和4.1,对表型变异的解释率分别为11.6％、11.8％、11.2％和11.8％,且这4个QTL抗性等位基因都来自低垩白亲本CPSLO17.