Culm Length Research Articles

Planned snow compaction approach (yuki-fumi) contributes toward balancing wheat yield and the frost-kill of unharvested potato tubers

Snow compaction implements the thermal conditions compatible with both killing volunteer potatoes and good wheat growth. To reveal how soil freezing regulates volunteer potatoes without preventing the growth of winter wheat, we conducted experiments in a wheat field in Hokkaido, Japan (42°53′N, 143°05′E), from winter 2013 to summer 2017. Owing to the enhanced thermal conductivity of snowpack during cold periods, different timings and frequencies of snow compaction allowed us to target different soil temperatures and frost depths. In most years and blocks, snow compaction achieved soil frost depth >0.3 m and killed all potato tubers, but in 2016–17, soil frost depth was <0.3 m in DC, and 7% of potatoes sprouted. These findings indicate that snow compaction before a heavy snowpack can effectively kill tubers. Wheat grain yield did not differ among treatments except in 2013–14. Deep soil freezing did not always reduce the wheat yield, but delayed snowmelt and thus delayed growth enhanced the likelihood of plants experiencing higher air temperature at the early spike development stage. Although changes in yield components such as culm length and spikelet density were associated with varietal responses to temperature, warm conditions in 2014 reduced the dry matter and shortened the grain-filling period, resulting in a greater decrease in yield. Furthermore, rapid hard freezing and direct physical impact may have caused much greater injury to wheat under a shallow snowpack in 2013–14. Thus, our findings indicate that proper snow compaction can balance wheat production and kill unharvested potatoes in crop rotation, and except for hot summer, gentle procedure of grain-filling could compensate the grain weight even in less spring growth.

Genetic Diversity in Aus rice (Oryza sativa L.) Genotypes of Bangladesh

Genetic diversity in 31 traditional Bangladeshi Aus rice genotypes were studied under transplanted condition through Mahalanobis D2 statistic for grain yield and yield contributing characters. The genotypes were grouped into five clusters. The inter-cluster distances were higher than intra-cluster distances indicating wider genetic diversity among the genotypes of different clusters. The intra-cluster distances were lower in all the cases reflecting homogeneity of the genotypes within the clusters. The cluster II contained the highest number of genotypes (08) and the cluster I and III contained the lowest (05). The highest intra-cluster distance was noticed for the cluster II and the lowest for cluster IV. The highest inter-cluster distance was observed between cluster II and V followed by cluster III and V, cluster I and V and the lowest between cluster I and III. Regarding inter-cluster distance, the genotypes of cluster V showed high genetic distance from all other clusters. The genotypes from cluster V could be hybridized with the genotypes of other characters of other clusters for producing transgressive segregants. The highest cluster means for yield, effective tiller number and grain length, were obtained from cluster I; whereas the lowest mean value for yield, culm length, plant height and grain breadth were found in cluster II. Therefore, genotypes under cluster I, cluster II and cluster V might be selected for future breeding program as parents for crossing to produce new recombinants with desired traits.Bangladesh J. Agril. Res. 43(2): 253-266, June 2018

Semi-dwarf barley (Hordeum vulgare L.) brh2 and ari-l mutants are deficient in a U-box E3 ubiquitin ligase

Lodging is the process where crop plants fall over and lie on the ground due to strong winds and heavy precipitation. This problem reduces yield and increases the risk of fungal infections and pre-harvest germination. In order to avoid lodging, plant breeders utilize short-culm mutants, which often have a robust culm that can support the weight of a heavy spike. In barley (Hordeum vulgare L.), thousands of short-culm mutants have been isolated in breeding programs around the world. Our long-term goal is to reveal the genetic network underlying culm length, with the objective to provide an enlarged repertoire of genes and alleles suitable for future breeding of lodging resistant barley. In the present work we studied a group of allelic brh2 and ari-l mutants, which have a relatively strong semi-dwarf phenotype and are phenotypically similar to previously identified mutants deficient in brassinosteroid signalling or metabolism. The Brh2 gene is located in the centromeric region of chromosome 4H and we applied a candidate gene approach to identify the gene. Brh2 is orthologous to TUD1 in rice (Orysa sativa L.), which encodes a U-box E3 ubiquitin ligase. We identified one missense mutation, one nonsense mutation and four deletions of the complete Brh2 gene. The mutants could respond to exogenously applied brassinolide, which suggests that the apparent brassinosteroid deficient phenotype of barley brh2 and ari-l mutants is related to brassinosteroid metabolism rather than signalling.

Heritability and Predicted Gain of Twelve Traits in Fifty-five Upland Rice Varieties

The genetic information about upland rice traits in terms of heritability (H2b) and predicted gain expressed to the mean (RAM) could lead to an effective selection process in the upland varietal development. Fifty-five upland rice varieties (URVs) were evaluated using 12 traits in three seasons. Traits culm length (CL), days to 50% flowering (DF), days to maturity (DM), flag leaf length (FLL), flag leaf width (FLW), grain length (GL), grain width (GW), one thousand grain weight (OTGW), plant height (PH), panicle length (PL), productive tillers (PT) and yield (YCC) had an overall mean of 102.7 cm, 55.3 days, 91.2 days, 37.9 cm, 1.6 cm, 8.69 mm, 2.92 mm, 21.2 g, 120.6 cm, 26.5 cm, 6.7 tillers and 2.25 t/ha, respectively. STAR V2.01 provided a combined analysis of variance (ANOVA) and found a high significance among URVs in all traits with corresponding coefficient of variation range of 3.3% (DM) to 24.16% (YCC). H2b on the other hand had a range of 89.3% (PH) to 99.2% (OTGW) while RAM had a range of 14.5% (GL) to 91.7% (YCC). It was CL, DF, DM, FLL, GL, OTGW, PH, PL and YCC with H2b &gt;95% were highly heritable and FLL, FLW, PL and YCC with RAM &gt;30% were high in genetic gain. Therefore, bigger flag leaves (FLL and FLW) as first indicator and yield as last indicator could be recommended in deciding what genotypes to keep and develop in the upland breeding process.

Regeneration ecology of the climber Flagellaria guineensis (Flagellariaceae) in the Transkei Coastal Forests, South Africa

Earlier studies showed that local people benefit by harvesting culms of the “climbing bamboo” Flagellaria guineensis from Transkei Coastal Forests in South Africa. However, little is known about the regeneration ecology of this species that often forms tangles in forest stand conditions. This study assessed the regeneration ecology of F. guineensis in different forest stand conditions (forest gaps and edges, and closed canopy stands). Intensity ratings were applied to determine the monthly phenological states, i.e. presence and amount of phenological stages in Bulolo and Mtambalala Forests. Relatively few flowers and fruits were seen; in Mtambalala only during the rainy season and in Bulolo during the rainy and dry seasons. Regeneration (seedlings, shoots from rhizomes and at growing tips) was constant during the 12-month study period in both forests. This suggested that during the study period, this climbing bamboo was in an active vegetative growth stage but not in a reproductive stage. Culm development in forest stand conditions in Mnenga, Mtambalala and Manubi Forests showed significant differences (P ≤ 0.05) in cluster diameter, culm diameter and culm length but not in the number of culms per cluster (P > 0.05). Mean cluster and culm diameters were highest in Manubi (185.5 and 1.0 cm) and lowest in Mnenga (64.1and 0.8 cm). The longest culms were recorded in Manubi (11.1 m). Culm diameter and length differed significantly (P ≤ 0.05) between forest stand conditions, but not cluster diameter and culm numbers (P > 0.05). Culm numbers were not significantly related to cluster diameter; similarly culm length was not related to culm diameter. Flowering and fruiting of F. guineensis differed between seasons and sites, and culm development is influenced by forest stand conditions and differed between forests. Recommendations for more sustainable harvesting of culms for basket-making included focusing on tangles in tree crowns to be harvested during the dry season with minimal flowering or fruiting, further studies on growth of seedlings and shoots into the forest canopy, and productive cultivation of this climbing bamboo outside the forest.

Genetic Analysis and Mapping of Genes for Culm Length and Internode Diameter in Progeny from an Interspecific Cross in Rice

Genetic Analysis and Mapping of Genes for Culm Length and Internode Diameter in Progeny from an Interspecific Cross in Rice

Allometric Equations for Predicting Culm Surface Area of Three Bamboo Species (Phyllostachys spp.)

It is strongly debated whether bamboo forest ecosystems are a carbon sink or a carbon source because of insufficient knowledge regarding carbon loss via CO2 emissions from these forests. The surface area (S) of bamboo culms (stems) is important for estimating culm respiration, a major component of carbon cycling in bamboo forests. However, few studies have attempted to formulate predictive equations for S. In this study, we developed allometric equations for predicting S in three bamboo species grown in Kyushu Island, western Japan: Phyllostachys pubescens Mazel ex Houz., P. bambusoides Sieb. et Zucc. and P. nigra var. henonis. We used a power equation between S and diameter at breast height (D) and a linear equation between S and D × total culm length (H). The results indicated that P. bambusoides and P. nigra shared common site-independent equations. In contrast, P. pubescens required species-specific equations due to interspecific variation in culm slenderness and tapering. We also found that D was a better predictive variable than DH when quantifying S because of its satisfactory predictive performance and simplicity. These findings will be beneficial for evaluating the contribution of bamboo forest ecosystems to carbon cycling.

Haplotype-based allele mining in the Japan-MAGIC rice population

Multi-parent advanced generation inter-cross (MAGIC) lines have broader genetic variation than bi-parental recombinant inbred lines. Genome-wide association study (GWAS) using high number of DNA polymorphisms such as single-nucleotide polymorphisms (SNPs) is a popular tool for allele mining in MAGIC populations, in which the associations of phenotypes with SNPs are investigated; however, the effects of haplotypes from multiple founders on phenotypes are not considered. Here, we describe an improved method of allele mining using the newly developed Japan-MAGIC (JAM) population, which is derived from eight high-yielding rice cultivars in Japan. To obtain information on the haplotypes in the JAM lines, we predicted the haplotype blocks in the whole chromosomes using 16,345 SNPs identified via genotyping-by-sequencing analysis. Using haplotype-based GWAS, we clearly detected the loci controlling the glutinous endosperm and culm length traits. Information on the alleles of the eight founders, which was based on the effects of mutations revealed by the analysis of next-generation sequencing data, was used to narrow down the candidate genes and reveal the associations between alleles and phenotypes. The haplotype-based allele mining (HAM) proposed in this study is a promising approach to the detection of allelic variation in genes controlling agronomic traits in MAGIC populations.

Morpho-biometric characterisation of Brachiaria spp germplasm in the area of mount Cameroon

Brachiaria grass has a major potential to relieve the polygastric livestock sector and support its growth in pastoral and extensive mixed systems where ruminants suffer permanent or seasonal nutritional stress from inadequate feed supply as an endemic problem. Morphological description of Brachiaria spp germplasm is helpful for the identification and delimitation of taxa that could lead to accession collections and selection of varieties with high agronomy value. The identification of potential accessions of Brachiaria in the mount Cameroon area was phenotypically based on twelve qualitative and eleven quantitative descriptors, data been collected using a structured questionnaire. The Brachiaria spp have light green coloured leaves (70.9%) which are mostly pubescent (34.5%), intermediate (29.1%) or glabrous (25.5%). The internodes are mostly yellow green (25.5%), the stigma is mostly white (40.0%) while the own panicle is mostly absent. The panicles are mostly open (61.8%) while the grains are mostly round shaped (74.5%). The glumella pubescence is mostly absent while the lemma and palea mostly have a straw colour and the apiculus and/or awn colour are mostly absent (74.5%). There is huge variability for the quantitative traits whatever the locality is. The traits varying most are the number of panicle per plant (146.86%), the grain weight (141.17%) and the number of spikelets per plant (135.10%). The correlation between measurements vary from weak to moderate, the highest positive significant (p<0.01) correlation coefficient (0.637**) was observed between the flag leaf length and the panicle length, while the significant native correlation (-0.283*) was found between the panicle fertility and the flag leaf width. The cumulative variance of the first five principal components explains 73.958% the genetic variability observed within the studied population. The flag leaf length, flag leaf width and culm length are components contributing most to that variability, with respectively 23.10%, 17.16% and 13.16%, giving a total cumulative genetic variability value of 53.43% of the whole Brachiaria spp population germplasm in the area of mount Cameroon. The hierarchical clustering revealed that there could exist four main clusters or accessions of Brachiaria spp germplasm in the area of mount Cameroon. Accession 4 is the most distant from the three others, while accessions 1 and 2 are the closest. The clustering into groups of accessions with similar morphological within the collection Brachiaria germplasm in this study will enable researchers interested in this grass to easily identify subsets of accessions for further evaluation aimed at specific uses. Morphological differences between these accessions and taxonomic differentiation to species level will need molecular characterization for confirmation.

紫耳箭竹克隆形态可塑性对典型冠层结构及光环境的响应

PDF HTML阅读 XML下载 导出引用 引用提醒 紫耳箭竹克隆形态可塑性对典型冠层结构及光环境的响应 DOI: 10.5846/stxb201710161859 作者: 作者单位: 西南大学生命科学学院，三峡库区生态环境教育部重点实验室,西南大学生命科学学院，三峡库区生态环境教育部重点实验室,西南大学生命科学学院，三峡库区生态环境教育部重点实验室,西南大学生命科学学院，三峡库区生态环境教育部重点实验室,西南大学生命科学学院，三峡库区生态环境教育部重点实验室,西南大学生命科学学院，三峡库区生态环境教育部重点实验室,三峡库区生态环境教育部重点实验室，西南大学生命科学学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31570612） Response of clonal morphological plasticity of Fargesia decurvata to different forest canopy structures and light conditions Author: Affiliation: Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, School of Life Science, Southwest University,,,,,,Key Laboratory of Eco-Environments in Three Gorges Reservoir Region, School of Life Science, Southwest University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在重庆金佛山国家自然保护内，选择了3种典型群落类型（落叶阔叶林、常绿落叶阔叶混交林和常绿阔叶林），使用Hemiview数字植物冠层分析系统量化群落冠层结构和光环境特征，并对林下紫耳箭竹（Fargesia decurvata）的形态可塑性特征进行调查，分析冠层结构和光环境特征改变下紫耳箭竹形态可塑性的差异，并探讨它们之间的相互关系。结果表明：（1）随着落叶阔叶林→常绿落叶阔叶混交林→常绿阔叶林演替的进行，群落的冠层开度降低，叶面积指数增加，平均叶倾角变小，趋于水平化，冠层对光的截获能力提高，林下光照的强度降低（P < 0.05）。（2）随着光照强度的降低，紫耳箭竹分株矮小化，叶片变窄，生物量积累降低，但通过增大比茎长、叶面积率和比叶面积提高对光的利用效率，并增大分枝角度和比隔长有效适应弱光环境。（3）在光照条件差的常绿阔叶林下，紫耳箭竹降低对地下茎的投资，将较多的生物量用于秆的增高增长和叶片的生长；而在光照条件好的落叶阔叶林环境下，紫耳箭竹降低对枝、叶生物量的分配，则加大对地下茎的投资，可认为是克隆植物对水分资源所表现的一种觅食行为。研究表明，紫耳箭竹种群随着冠层结构的改变发生了明显的可塑性变化，这些可塑性变化是种群对冠层结构和光环境差异的适应性反应的结果，有利于增强种群对异质生境中光资源的获取和利用；群落内部可以通过调控冠层结构的改变协调和控制小径竹种群的发展。 Abstract:Clonal morphological plasticity, closely related to the maintenance and regeneration of populations, is the ability for a plant to adapt to a changing environment. In a field experiment, the Hemiview digital canopy analysis system was used to measure the canopy structures (canopy openness, CO; leaf area index, LAI; mean leaf angle, MLA) and light conditions (direct solar radiation under canopy, Dir; diffuse solar radiation under canopy, Dif; Total solar radiation under canopy, Tot) in three typical forest types (deciduous broad-leaved forest, evergreen and deciduous broad-leaved mixed forest, evergreen broad-leaved forest) in Jinfo Mountains National Nature Reserve, Chongqing. The clonal morphological plasticity of understory dwarf bamboo, Fargesia decurvata, was also measured. Moreover, the relationship between canopy structure and morphological plasticity of F. decurvata was discussed. The results showed that:(1) With the development of forest succession, the CO and MLA decreased, but LAI increased, resulting in the increase in light interception capability of forest canopy and the decrease in the light intensity under forest canopy (P < 0.05). (2) Forest canopy condition had a significant effect on the morphological plasticity of F. decurvata ramets. With the decrease in light intensity, the culm height, basal diameter, leaf area, and biomass of F. decurvata ramets decreased. However, decreased light intensity can increase the specific culm length, leaf area ratio, and specific leaf area to improve the utilization efficiency of light and increase the branch angle of spacer and specific spacer length to adapt to low light environments. (3) Under the low light environment in an evergreen broad-leaved forest, F. decurvata reduced its investment in rhizome but allocated more biomass for culm and leaf growth. However, in the deciduous broad-leaved forest, F. decurvata reduced the allocation of branches and leaves and increased the investment in rhizome growth (spacer length and diameter), which can be considered as a foraging behavior to searching much more water resources. These results suggested that the morphological plasticity of F. decurvata underwent significant change in different forest canopies, which is the result of adaptive response to different forest canopy structures and light conditions and enhances the ability to acquire and utilize light resources in heterogeneous light environments. Moreover, the communities may be able to coordinate and control the development of dwarf bamboo by controlling the change of canopy structures and light conditions. 参考文献 相似文献 引证文献

Genetic Performance of the Semidwarfing Allele sd1 Derived from a Japonica Rice Cultivar and Minimum Requirements to Detect Its Single-Nucleotide Polymorphism by MiSeq Whole-Genome Sequencing.

The influence of the semidwarfing gene sd1 derived from the rice cultivar Jukkoku (Jukkoku_sd1) and IR8 (IR8_sd1), which contributed to the Green Revolution, d60 from Hokuriku 100, as well as the combination of sd1 and d60 (Jukkoku_sd1 plus d60 and IR8_sd1 plus d60), was investigated using isogenic lines raised by backcrossing with the cultivar Koshihikari. The isogenic lines carrying Jukkoku_sd1, IR8_sd1, d60, Jukkoku_sd1 plus d60, and IR8_sd1 plus d60 had considerably shorter culm lengths than Koshihikari by 19.2%, 22.8%, 26.0%, 45.1%, and 43.4%, respectively. The sd1 plus d60 lines showed additively reduced culms, indicating that the function of d60 was different from sd1. In contrast to the culm reduction, Jukkoku_sd1 showed productive merit with a panicle length of 2.5% greater than the origin. MiSeq next-generation sequencer was used to optimize a minimum scale to detect Jukkoku_sd1 in practical breeding. Mapping with the reference genome of Nipponbare gained the average depths of Koshihikari Jukkoku_sd1 and Koshihikari being 9.17 and 7.29, respectively. Comparing the vcf files of the entire genomes of Koshihikari Jukkoku_sd1 and the virtual Koshihikari revealed a G to T SNP at position 38,382,746 in the sd1 locus on chromosome 1 of Koshihikari, causing a loss-of-function mutation of GA20-oxidase.

Statistical Analysis of Foreign Rice Phenotypes under Different Seasons of the Philippines

Korean rice is a foreign genetic resources in the Philippines that has to be characterized for its proper germplasm utility. Ten Korean phenotypes were analyzed using correlation, clustering and principal component analyses (PCA) based on the 13 traits viz., culm length (CL), days to 50% flowering (D50F), days to maturity (DM), filled grains per panicle (FGP), flag leaf length (FLL), flag leaf width (FLW), grain length (GL), grain width (GW), grain yield (GY), plant height (PH), productive tillers (PT), spikelet fertility SF) and thousand grain weight (TGW) under different seasons of the Philippines. It was found out that Korean phenotypes had earlier D50F and DM, shorter PH and CL, more PT, FGP and SF, and higher GY under dry than wet season. Each season had three groups based on the clustering analysis with a pattern of group 1 having phenotypes with heavy TGW, early D50F and DM, short PH and FLL; and more FGP, SF and GY; group 2 having long CL, wide FLW, light TGW; and late D50F and DM; and group 3 having short CL, narrow FLW and low PT. Correlation in FGP, PT and SF to GY was consistently high positive (r≥0.68) in two seasons. Also, PCA consistently showed that GY, PH and PT were the highest contributor of variation with an average of 21.42% in two seasons. Korean GY therefore was highly variable but attaining higher GY can be possible by utilizing grain-filling (FGP and SF) and productive tillering (PT) traits as selection indices in the breeding program.

Contribution of basal and aerial tillers to forage production dynamics in Tifton-85 bermudagrass irrigated with fishpond wastewater and fertilized with NPK

This paper aims to assess the contribution of basal and aerial tillers to structural and productive characteristics of Tifton 85 bermudagrass, irrigated with fish tank wastewaters and fertilized with NPK. The experiment was conducted in the city of Petrolina-PE, Northeastern Brazil. The evaluated area had 960 m2 subdivided into five treatments and ten replicates, in a completely randomized design. Treatments consisted of different fertilization rates of NPK (0, 33, 67, 100, and 150%) as recommended by the Handbook of Fertilization Recommendations for the State of Pernambuco, and based on a prior soil analysis. Irrigation water came from fishponds with Nile Tilapia fingerlings. The experiment was divided into four intervals of 27, 29, 18, and 21 days respective to the first, second, third, and fourth cuts. Both tiller types were analyzed for number of individuals, culm length and diameter, fully- and partially-expanded leaves, leaf length and width (fully or partially expanded), dry mass of leaves (fully and partially expanded and total), culm, dead tissue, and total tiller, and the ratio of leaf and culm. Both structural and productive characteristics showed a linear growth trend for both types, with emphasis on the basal tillers. Thus, a suitable supply of nutrients is crucial for grasses, mainly NPK, as these are macronutrients of vital importance in physiological processes. In addition to the nutrients supplied via fish farming wastewater, fertilization with 150% of the recommended amount of NPK promoted a greater structural development of the tillers, increasing their productivity levels.

Mutations in the gene of the G\u03b1 subunit of the heterotrimeric G protein are the cause for the brachytic1 semi-dwarf phenotype in barley and applicable for practical breeding

BackgroundShort-culm mutants have been widely used in breeding programs to increase lodging resistance. In barley (Hordeum vulgare L.), several hundreds of short-culm mutants have been isolated over the years. The objective of the present study was to identify the Brachytic1 (Brh1) semi-dwarfing gene and to test its effect on yield and malting quality.ResultsDouble-haploid lines generated through a cross between a brh1.a mutant and the European elite malting cultivar Quench, showed good malting quality but a decrease in yield. Especially the activities of the starch degrading enzymes β-amylase and free limit dextrinase were high. A syntenic approach comparing markers in barley to those in rice (Oryza sativa L.), sorghum (Sorghum bicolor Moench) and brachypodium (Brachypodium distachyon P. Beauv) helped us to identify Brh1 as an orthologue of rice D1 encoding the Gα subunit of a heterotrimeric G protein. We demonstrated that Brh1 is allelic to Ari-m. Sixteen different mutant alleles were described at the DNA level.ConclusionsMutants in the Brh1 locus are deficient in the Gα subunit of a heterotrimeric G protein, which shows that heterotrimeric G proteins are important regulators of culm length in barley. Mutant alleles do not have any major negative effects on malting quality.

Molecular Mapping of QTLs Associated with Lodging Resistance in Dry Direct-Seeded Rice (Oryza sativa L.).

Dry direct-seeded rice (DSR) is an alternative crop establishment method with less water and labor requirement through mechanization. It provides better opportunities for a second crop during the cropping season and therefore, a feasible alternative system to transplanted lowland rice. However, lodging is one of the major constraints in attaining high yield in DSR. Identification of QTLs for lodging resistance and their subsequent use in improving varieties under DSR will be an efficient breeding strategy to address the problem. In order to map the QTLs associated with lodging resistance, a set of 253 BC3F4 lines derived from a backcross between Swarna and Moroberekan were evaluated in two consecutive years. A total of 12 QTLs associated with lodging resistance traits [culm length (qCL), culm diameter (qCD), and culm strength (qCS)] were mapped on chromosomes 1, 2, 6, and 7 using 193 polymorphic SNP markers. Two major and consistent effect QTLs, namely qCD1.1 (with R2 of 10%) and qCS1.1 (with R2 of 14%) on chromosome 1 with id1003559 being the peak SNP marker (flanking markers; id1001973-id1006772) were identified as a common genomic region associated with important lodging resistance traits. In silico analysis revealed the presence of Gibberellic Acid 3 beta-hydroxylase along with 34 other putative candidate genes in the marker interval region of id1001973-id1006772. The positive alleles for culm length, culm diameter, and culm strength were contributed by the upland adaptive parent Moroberekan. Our results identified significant positive correlation between lodging related traits (culm length diameter and strength) and grain yield under DSR, indicating the role of lodging resistant traits in grain yield improvement under DSR. Deployment of the identified alleles influencing the culm strength and culm diameter in marker assisted introgression program may facilitate the lodging resistance under DSR.

Markers Associated with Culm Length and Elongated Internode Length in Japonica Rice

Culm length (CL) is composed of different elongated internode lengths (EILs) and is closely correlated to the lodging resistance in rice (Oryza sativa L.). The objective of this study was to identify quantitative trait loci (QTLs) stably associated with CL and the first to fourth EIL from panicle base, which were abbreviated as FIL (first), SIL (second), TIL (third), and FOIL (fourth) in japonica rice, respectively. Association mapping was conducted using the genotypes determined by 154 simple sequence repeat markers and the phenotypes in 2010, 2011, and 2015 of 331 japonica rice accessions. The study mapped 6, 5, 15, 2, and 2 QTLs tagged by 22 markers on eight chromosomes and stably associated with CL, FIL, SIL, TIL, and FOIL, respectively. Five QTLs, qCL‐6‐2, qFIL‐6‐5, qSIL‐6‐2, qTIL‐6‐3, and qFOIL‐7‐5, explained the largest phenotypic variance of CL, FIL, SIL, TIL, and FOIL, respectively. RM1340, RM1374, RM281, RM233, and RM225 were stably and specifically associated with CL, FIL, SIL, TIL, and FOIL, respectively. Forty‐three effective alleles were identified. Four and three donors with negative and positive alleles were recommended. There was a highly significant phenotypic difference between accessions with or without effective alleles. These QTLs, associated markers, effective alleles, and their donors could be used to improve CL and specific EIL in japonica rice.

Short and Solid Culm/RFL/APO2 for culm development in rice.

The culm development of rice is characterized by elongation and medullary cavity (MC) formation, which are determined by node formation meristem and residual meristem, respectively. Although many factors have been shown to affect culm elongation, molecules involved in MC formation remained to be identified. In this study, we show that a point mutation in SHORT and SOLID CULM (SSC), the rice homologue of Arabidopsis LFY, resulted in plants with drastically reduced culm length and completely abolished MC formation. Analysis of transgenic plants with moderately enhanced SSC expression revealed significant decreases in plant height and MC size in contrast to slight changes in heading date, indicating that the culm developmental process is much more tightly monitored by the gene. Transcriptomic analysis revealed the differential expression of knotted-1 like homeobox (KNOX) protein genes and gibberellin (GA) metabolic genes in the ssc mutant background, and most of the genes contained well-conserved LFY-binding cis-elements that could be effectively recognized by SSC. Genetic analysis found that the reduced culm length of the mutant could be largely rescued by the GA-accumulating mutation eui, whereas MC formation remained unchanged in the double mutant plants. Taken together, our results suggest that SSC affects culm elongation mainly through maintaining GA homeostasis, while functions in MC formation by mediating residual meristem activity possibly via the KNOX pathway. The present study provides a potential strategy for improving the culm morphology and plant architecture in rice by manipulating SSC and/or its downstream components.

Overexpression of TIFY genes promotes plant growth in rice through jasmonate signaling.

Because environmental stress can reduce crop growth and yield, the identification of genes that enhance agronomic traits is increasingly important. Previous screening of full-length cDNA overexpressing (FOX) rice lines revealed that OsTIFY11b, one of 20 TIFY proteins in rice, affects plant size, grain weight, and grain size. Therefore, we analyzed the effect of OsTIFY11b and nine other TIFY genes on the growth and yield of corresponding TIFY-FOX lines. Regardless of temperature, grain weight and culm length were enhanced in lines overexpressing TIFY11 subfamily genes, except OsTIFY11e. The TIFY-FOX plants exhibited increased floret number and reduced days to flowering, as well as reduced spikelet fertility, and OsTIFY10b, in particular, enhanced grain yield by minimizing decreases in fertility. We suggest that the enhanced growth of TIFY-transgenic rice is related to regulation of the jasmonate signaling pathway, as in Arabidopsis. Moreover, we discuss the potential application of TIFY overexpression for improving crop yield.

벼의 이상적인 초형에 관여하는 QTL 분석

본 실험은 청청과 낙동 조합을 약배양하여 육성한 120 계통을 이용하여 이상적인 초형에 관련된 간장, 수장, 개체당 이삭수에 대한 QTLs를 분석하고 탐색된 QTLs은 다음과 같은 결과를 얻었다. 모부본인 청청과 낙동의 간장의 평균은 <TEX>$75.3{\pm}6.72cm$</TEX>, 수장의 평균은 <TEX>$20.6{\pm}2.08cm$</TEX>이었으며 개체당 이삭수의 평균은 <TEX>$16.0{\pm}2.37$</TEX>개로 나타났다. 120 계통의 CNDH의 간장의 평균은 <TEX>$71.6{\pm}17.38cm$</TEX>였으며, 수장의 평균은 <TEX>$20.3{\pm}2.24cm$</TEX>였으며 개체당 이삭수의 평균은 <TEX>$16.1{\pm}7.17$</TEX>개로 나타났다. 이에 대한 CNDH 계통의 빈도분포표의 곡선은 정규분포에 가까운 연속변이를 나타내었다. 간장, 수장, 개체당 이삭수 QTL 분석결과 간장에서 1번 염색체의 qPlL1-1, qPlL1-2, 5번 염색체의 qPlL5, 수장에서 2번 염색체의 qPL2, 3번 염색체의 qPL3, 10번 염색체의 qPL10, 개체당 이삭수에서 1번 염색체의 qPN1-1, qPN1-2, 9번 염색체의 qPN9이 탐색되었다. 간장에 대한 QTL에서 5번 염색체의 LOD 값은 3.81, 상가적 값은 5.49였으며, 수장에 대한 QTL에서 2번 염색체의 LOD 값은 7.13, 상가적 값은 -2.58 이었으며, 3번 염색체의 LOD 값은 3.20, 상가적 값은 0.88로 나타났다. 개체당 이삭수에 대한 QTL에서 9번 염색체의 LOD 값은 4.27, 상가적 값은 -1.60으로 나타났다. 초형 관련 분석 결과에서 탐색된 9개 마커를 토대로 간장에 대한 RM5311, 수장에 대한 RM555, 개체당 이삭수에 대한 RM8111을 선발하여 모부본인 청청, 낙동을 기준으로 자포니카형 22 품종, 인디카형 12 품종에 다형성을 분석하였다. 그림4와 같이 청청과 낙동과 같은 밴드양상을 나타나거나 다른크기상태의 밴드양상을 나타내었다. 간장, 수장, 개체당 이삭수의 일치율은 각각 44.11%, 41.17%, 44.11%로 나타났다. Rice is the staple food of at least half of the world's population. Due to global warming, the weather is difficult to forecast nowadays. Therefore, it is necessary to breed various breeding to respond to such changes in the environment. This study was conducted to analyze the QTL about plant form, culm length, ear number and ear length by using 120 lines by anther culture, a cross between the Indica variety Cheongcheong and Japonica variety Nagdong. DNA marker was selected on the QTLs gene, and the following results were obtained. CNDH (Cheongcheong Nagdong Doubled Haploid) lines frequency distribution table curves about culm length, ear number and ear length exhibited showed a continuous variation close to a normal distribution. QTL analysis result, on culm length qPlL1-1 and qPlL1-2 were detected on the chromosome 1 and qPlL5 was detected on the chromosome 5. However, on ear length qPL2, qPL3 and qPL10, were detected on the chromosome 2, 3 and 10, while on ear number qPN1-1 and qPN1-2 were detected on the chromosome 1, qPN9 was detected on the chromosome 9. The QTLs related to culm length was found to chromosomes 5 and LOD scores were 3.81. The QTLs related to ear length was found to chromosomes 2 and 3 LOD scores were 7.13 and 3.20. The QTLs related to ear number was found to chromosome 9 and LOD scores were 4.27. Twenty two (22) Japonica cultivars and 12 Indica cultivars were analyzed polymorphisms, using selected 9 markers from the result about plant form analysis. RM5311, RM555 and RM8111 about the culm length, the ear length and number of ear were selected on the standard of Cheongcheong and Nagdong. Each rate of concordances about the culm length, the ear length and number of ear are 44.11%, 41.17% and 44.11%.

水稲新品種「空育139号」の栽培特性 : 幼穂形成期の茎数と収量、稈長および穂揃い日数の関係

水稲新品種「空育139号」の栽培特性 : 幼穂形成期の茎数と収量、稈長および穂揃い日数の関係