<div>Sorghum, which is grown internationally as a cereal crop that is robust to heat, drought, and disease, has numerous applications for food, forage, and biofuels. When monitoring the growth stages of sorghum, or phenotyping specific traits for plant breeding, it is important to identify and monitor the panicles in the field due to their impact relative to grain production. Several studies have focused on detecting panicles based on data acquired by RGB and multispectral remote sensing technologies. However, few experiments have included hyperspectral data because of its high dimensionality and computational requirements, even though the data provide abundant spectral information. Relative to analysis approaches, machine learning, and specifically deep learning models have the potential of accommodating the complexity of these data. In order to detect panicles in the field with different physical characteristics, such as colors and shapes, very high spectral and spatial resolution hyperspectral data were collected with a wheeled-based platform, processed, and analyzed with multiple extensions of the VGG-16 Fully Convolutional Network (FCN) semantic segmentation model.</div><div><br></div><div>In order to have correct positioning, orthorectification experiments were also conducted in the study to obtain the proper positioning of the image data acquired by the pushbroom hyperspectral camera at near range. The scale of the DSM derived from LiDAR that was used for orthorectification of the hyperspectral data was determined to be a critical issue, and the application of the Savitzky-Golay filter to the original DSM data was shown to contribute to the improved quality of the orthorectified imagery.</div><div><br></div><div>Three tuned versions of the VGG-16 FCN Deep Learning architecture were modified to accommodate the hyperspectral data: PCA&FCN, 2D-FCN, and 3D-FCN. It was concluded that all the three models can detect the late season panicles included in this study, but the end-to-end models performed better in terms of precision, recall, and the F-score metrics . Future work should focus on improving annotation strategies and the model architecture to detect different panicle varieties and to separate overlapping panicles based on an adequate quantities of training data acquired during the flowering stage.</div>

During the past two decades, panicle-feeding Hemiptera have become pests of sorghum in West and Central Africa, and particularly in Mali, where this is a staple food crop. Of the more than 100 sorghum insect pests reported in Africa, 42 species were found to be panicle-feeding pests. Prior to this study, no research had been done on the paniclefeeding Hemiptera in South Africa. The objectives of the study were to determine the abundance and diversity of panicle-feeding Hemiptera on sorghum. A check list was compiled and the temporal distribution of different Hemiptera species determined during the different panicle stages of development. In addition, the effect of insecticide application on Hemiptera numbers was evaluated and the correlation between grain mould severity and Hemiptera feeding damage was investigated. To determine the abundance and diversity of Hemiptera on sorghum panicles, surveys were conducted between November 2004 and June 2006 at 26 sites in four provinces of South Africa. Two methods of collection were used viz. the plastic bag and D-Vac methods. The total number of the adults and nymphs collected during this study was 23 798. Forty-three different herbivorous Hemiptera species were collected. The most abundant family was the Miridae (41 %), followed by the Lygaeidae (17 %). Eurystylus spp., Calidea dregii, Campylomma sp., Creontiades pallidus, Nysius natalensis and Nezara viridula were the most abundant species and also occurred widely in the sorghum production area. Infestation levels of these species were low compared to that in other parts of Africa and it cannot be concluded that they have pest status in South Africa. There was no clear distinction between the stages during which panicles were infested by different species. The general tendency was that nearly all species were present from the flowering stage onwards and that numbers declined when grain hardened. In general, Campylomma sp. and C. pallidus numbers peaked during the flowering stage and Eurystylus spp. and N. natalensis during the milk stage. Hemiptera feeding damage resulted in an increase in incidence of seeds with discoloured germ, therefore contributing significantly to reduction in grain quality. / Thesis (M. Environmental Science (Plant Protection))--North-West University, Potchefstroom Campus, 2007.

During the past two decades, panicle-feeding Hemiptera have become pests of sorghum in West and Central Africa, and particularly in Mali, where this is a staple food crop. Of the more than 100 sorghum insect pests reported in Africa, 42 species were found to be panicle-feeding pests. Prior to this study, no research had been done on the paniclefeeding Hemiptera in South Africa. The objectives of the study were to determine the abundance and diversity of panicle-feeding Hemiptera on sorghum. A check list was compiled and the temporal distribution of different Hemiptera species determined during the different panicle stages of development. In addition, the effect of insecticide application on Hemiptera numbers was evaluated and the correlation between grain mould severity and Hemiptera feeding damage was investigated. To determine the abundance and diversity of Hemiptera on sorghum panicles, surveys were conducted between November 2004 and June 2006 at 26 sites in four provinces of South Africa. Two methods of collection were used viz. the plastic bag and D-Vac methods. The total number of the adults and nymphs collected during this study was 23 798. Forty-three different herbivorous Hemiptera species were collected. The most abundant family was the Miridae (41 %), followed by the Lygaeidae (17 %). Eurystylus spp., Calidea dregii, Campylomma sp., Creontiades pallidus, Nysius natalensis and Nezara viridula were the most abundant species and also occurred widely in the sorghum production area. Infestation levels of these species were low compared to that in other parts of Africa and it cannot be concluded that they have pest status in South Africa. There was no clear distinction between the stages during which panicles were infested by different species. The general tendency was that nearly all species were present from the flowering stage onwards and that numbers declined when grain hardened. In general, Campylomma sp. and C. pallidus numbers peaked during the flowering stage and Eurystylus spp. and N. natalensis during the milk stage. Hemiptera feeding damage resulted in an increase in incidence of seeds with discoloured germ, therefore contributing significantly to reduction in grain quality. / Thesis (M. Environmental Science (Plant Protection))--North-West University, Potchefstroom Campus, 2007.

L'architecture de la panicule de riz est l'un des caractères morphologiques majeurs du potentiel de rendement, sélectionné lors de sa domestication. Une panicule est une structure ramifiée, composée d'un axe principal (rachis), de branches primaires, et d'ordres supérieurs de branchement (branches secondaires et tertiaires) et enfin les épillets. Cette structure, qui dépend de l'activité des méristèmes axillaires au cours du développement de la panicule, montre une grande diversité à la fois inter-spécifique (espèces cultivées vs espèces sauvages apparentées) et intra-spécifiques (riz asiatique et / ou africain). Plusieurs gènes/QTL importants ont été caractérisés chez Oryza sativa pour le contrôle de l'architecture de la panicule en régulant l'identité des méristèmes, la division cellulaire et la signalisation hormonale. Cependant, les mécanismes liés à la diversité de la panicule de riz et son évolution dans le contexte de la domestication sont encore largement inconnus. Durant ma thèse, j'ai principalement contribué à l'étude des bases histologique et moléculaires de la diversité de la panicule entre l'espèce africaine Oryza glaberrima et Oryza barthii, l'espèce sauvage apparentée. J'ai analysé les profils d'expression d'orthologues à des gènes de O. sativa liés au développement de la panicule et participé à l'analyse transcriptomique de petits ARN dans les premiers stades de développement de la panicule. Ce travail a révélé une différence de période d'initiation et de niveau d'expression de ces gènes au cours du développement de la panicule entre les deux espèces, conjointement avec une forte conservation de leurs domaines d'expression. Les gènes qui favorisent l'activité des méristèmes sont sur-accumulés sur une période plus longue au cours du développement de la panicule chez l'espèce cultivée, tandis que les gènes liés au développement des épillets se comportent de manière opposée. Ces travaux ont également montré une altération similaire de l'expression des membres de la voie de siRNA phasés initiés par miR2118, voie connue pour être impliquée dans la gamétogenèse mâle. L'ensemble de ces résultats suggère que la diversité de complexité de la panicule chez les riz africains reposerait sur des altérations hétérochroniques de l'activité de ramification et de déterminisme des méristèmes d'épillets. / Rice panicle architecture is one of the most important morphological traits specifying rice yield potential, which was under selection during rice domestication. A panicle is a branched structure composed of a rachis, primary branches, higher order branches (i.e. secondary and tertiary branches) and finally spikelets. This morphology, depending on the activity of axillary meristems during its development, shows a wide diversity in both inter-specific (i.e. crops vs. wild-relatives) and intra-specific (Asian or/and African rice) levels. Several important genes/QTLs have been characterized in Oryza sativa as controlling panicle architecture by regulating meristem fate, cell division and hormone signaling. However the mechanisms related to rice panicle diversity and its evolution in the context of domestication are still largely unknown. During my PhD, I mainly investigated the histological and molecular bases of panicle diversity between the African species Oryza glaberrima and its wild-relative Oryza barthii. I analyzed the expression patterns of orthologs of O. sativa landmark genes related to panicle development and was involved in small RNA transcriptomic analysis in early stages of panicle development. This work revealed a high conservation of the spatial expression pattern of the landmarks genes studied but have highlighted a differential timing and level of the expression of these genes during the panicle development between two species. The genes promoting meristem activity were upper-accumulated over a longer period during the panicle development in the crop species, whereas the gene promoting spikelet/floret meristem fate behaved in opposite way. This work also has shown similar heterochronic alteration of the expression of members of the miR2118-triggered 21-nt phased siRNA pathway, known to be involved in male gametogenesis. Together, these findings suggest that variation of panicle complexity in African rice may rely on heterochronic changes in branching activity as well as spikelet/floret meristem determinacy.

京都大学 / 新制・課程博士 / 博士(農学) / 甲第24239号 / 農博第2518号 / 新制||農||1094(附属図書館) / 学位論文||R4||N5410(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 白岩 立彦, 教授 中﨑 鉄也, 教授 那須田 周平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-05-08T11:40:37Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_CezarAugustoVerdi.pdf: 1224238 bytes, checksum: 1c1a3c5dacea433a84a0663547ee817f (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-05-10T15:55:41Z (GMT) No. of bitstreams: 2 Dissertação_CezarAugustoVerdi.pdf: 1224238 bytes, checksum: 1c1a3c5dacea433a84a0663547ee817f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-10T15:55:41Z (GMT). No. of bitstreams: 2 Dissertação_CezarAugustoVerdi.pdf: 1224238 bytes, checksum: 1c1a3c5dacea433a84a0663547ee817f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-04 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Aveia branca é uma cultura de particular importância para a os sistemas de cultivos brasileiros, com maior importância econômica na Região Sul. Entre os múltiplos propósitos, destaca-se na produção de grãos de excelente qualidade para a alimentação humana. Constantes trabalhos de melhoramento genético e pesquisas fitotécnicas, tem possibilitado o crescimento da importância desse cereal. Os maiores desafios para o melhoramento são o desenvolvimento de cultivares com ampla adaptação, que respondam eficientemente em diferentes ambientes. A seleção de genótipos promissores encontra dificuldades pela origem dita complexa da maioria dos caracteres de interesse agronômico e sua interação com o ambiente de seleção. Com isso, algumas estratégias diferenciadas devem ser analisadas visando melhorar o ganho na seleção de genótipos superiores para diversos caracteres, bem como, a seleção de genótipos com adaptação aos mais variados ambientes. Este estudo propõe analisar estratégias de seleção aplicadas em geração inicial e a influência promovida por diferentes ambientes de seleção, na obtenção de genótipos com destaque no rendimento de grãos e qualidade industrial. Foram utilizadas seis combinações que sofreram seleção inicial (F2) quanto ao rendimento de grãos por planta, índice de grãos maior que dois milímetros e massa da panícula. Formou-se 24 bulks, os quais foram conduzidos durante três anos em Capão do Leão – RS e Augusto Pestana – RS. Posteriormente na geração F7 todos os bulks foram conduzidos em Capão do Leão – RS, totalizando assim 48 bulks, além dos genitores e testemunhas comerciais. O delineamento experimental foi de blocos casualizados com três repetições. As seleções via massa da panícula principal e rendimento de grãos por planta são eficientes, mas devem combinar o índice de grãos, para elevar a qualidade industrial. Genótipos complementares são mais eficientes na obtenção de recombinantes superiores independentemente do ambiente de seleção. Os caracteres massa da panícula e massa do hectolitro são promissores para a seleção inicial, porém, devem ser aliados ao índice de grãos, índice de descasque e número de grãos por panícula para melhorar a aptidão industrial. / Oat is a culture of particular importance to the Brazilian farming systems, with greater economic importance in the southern region. Among the multiple purposes, stands out in the production of excellent quality grain for human consumption. Constants works of breeding and phytotechnical research has enabled the growth of the importance of this cereal. The greatest challenges are to improve the development of cultivars with wide adaptation, which efficiently respond in different environments. The selection of promising genotypes is difficult by the complex said source of most agronomically important traits and their interaction with the selection environment. With this, some different strategies should be analyzed to improve the gain in the selection of superior genotypes for various characters, as well as the selection of genotypes with adaptation to the most varied environments. This study proposes to analyze selection strategies applied in early generation and the influence promoted by different selection environments in obtaining genotypes with emphasis on grain yield and industrial quality. Six combinations were used that have undergone initial selection (F2) and grain yield per plant, grain index greater than two millimeters and panicle weight. Formed 24 bulks, which were conducted for three years in Capão do Leão - RS and Augusto Pestana - RS. Later in the generation F7 all bulks were conducted in Capão do Leão - RS, totaling 48 bulks, in addition to parents and commercial checks. The experimental design was a randomized block design with three replications. The selections via panicle weight and grain yield per plant are efficient, but must match the grain index, to raise industrial quality. Complementary genotypes are more effective in achieving superior recombinant regardless of selection environment. The mass character of panicle and mass of hectoliter are promising for the initial selection, however, must be coupled with the grain index, peel index and number of grains per panicle to improve industrial capability.

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No. of bitstreams: 2 dissertação Vianei.pdf: 1386887 bytes, checksum: 786b3765350d438130b834ddea46e8ef (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-06 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / A aveia branca é um cereal de grande importância para a agricultura brasileira, com destaque em algumas regiões onde a cultura é parte fundamental dos sistemas produtivos. Dentre as inúmeras utilizações do cereal, vem ganhando destaque o seu uso na alimentação humana. Devido as suas características nutricionais o cereal é qualificado como alimento funcional, auxiliando na prevenção de doenças e o seu consumo é indicado por vários órgãos de saúde. Os programas de melhoramento genético de plantas possuem o desafio de fornecer aos produtores e indústria beneficiadora genótipos que tenham bom desempenho produtivo aliado a boas características nutricionais. Dessa forma, cada programa deve definir e estabelecer estratégias de seleção que atendam os seus objetivos a um custo baixo e num curto período de tempo. Dentre os métodos de condução de populações segregantes se destaca o SSD (Single Seed Descent) que, entre suas vantagens, possibilita ao melhorista a manutenção da variabilidade total da população em gerações avançadas e a possibilidade de avanço de mais de uma geração por ano. Assim como em outros métodos, o SSD é executado por alguns programas com alterações. Estas visam aumentar a variabilidade genética da população segregante por meio da condução de mais sementes a partir de uma planta F2. Este trabalho teve por objetivo avaliar famílias F6 oriundas de dois cruzamentos de aveia branca (Albasul x UPF 15 e IAC 7 x UFRGS 19) conduzidas sob os métodos de condução: SSD Clássico e SSD Modificado. O experimento foi conduzido no município de Capão do Leão – RS, no ano de 2016. Foram avaliadas 30 famílias de cada cruzamento conduzidas no método SSD clássico e 120 famílias de cada cruzamento conduzidas no método SSD modificado. Foi possível observar que o método SSD Modificado proporciona uma maior amplitude entre os valores mínimos e máximos para a maioria dos caracteres avaliados. A elevação do teto produtivo não resultou, no entanto, em um aumento expressivo nas médias das famílias. O método SSD Modificado apresenta um maior efeito não aditivo atuando entre e dentro das famílias, afetando negativamente a herdabilidade no sentido restrito. Nas famílias oriundas do cruzamento Albasul x UPF 15 os ganhos de seleção foram superiores naquelas conduzidas no método SSD. No cruzamento IAC 7 x UFRGS 19 o método SSD também obteve desempenho superior nos ganhos de seleção com exceção nos caracteres estatura de planta e massa de grãos da panícula principal. Quando são analisadas as médias das famílias selecionadas na pressão de seleção de 10% e 20% há uma semelhança entre os dois métodos de condução. Destaca-se o método SSD Modificado que engloba um número maior de genótipos com bom desempenho agronômico e que agregam desempenho destacado para vários caracteres de interesse. Dessa forma as modificações efetuadas no método SSD foram benéficas para o programa de melhoramento e 8 possibilitaram a identificação de um maior número de genótipos transgressivos com o mesmo número de plantas F2. / The white oat is a cereal of great importance for Brazilian agriculture, with emphasis in some regions where the culture is the fundamental part of productive sistems. Among the inumerable uses of the cereal has been emphasized in the human food. Due to the nutritional characteristics the cereal is qualified as functional food, aiding in the prevention of diseases and its consumption is indicated by several health organs. The genetic breeding programs have the challenge of providing genotypes to the producers and the processing industry with good productive characteristics, together with good nutritional characteristics. In this way each program must define and establish selection strategies that meet its objectives at a low cost and in a short period of time. Among the methods Among the methods of conducting segregating populations, SSD stands out, which among its advantages enables the breeder to maintain the total population variability in advanced generations and the possibility of advancement of more than one generation per year. Like other methods the SSD is run by some programs with changes. These aim to increase the genetic variability of the segregating population by conducting more seeds from an F2 plant. The objective of this work was to evaluate F6 families from two white oat crosses (Albasul x UPF 15 and IAC 7 x UFRGS 19) conducted under the conduction methods: Classic SSD and Modified SSD. The experiment was conducted in the county of Capão do Leão – RS, in the year of 2016. Was evaluated 30 families of each crosses conducted in the classic SSD method and 120 families in each cross conducted in the modified SSD method. It was possible to observed that the modified SSD method provides a greater range between minimum and maximum values for most of the evaluated characters. The Modified SSD method has a greater non-additive effect acting between and within families, negatively affecting heritability in the narrow sense. In the families from the Albasul x UPF 15 cross the selection gains were higher in the families conducted in the SSD method. At the IAC 7 x UFRGS 19 cross the SSD method also obtained superior performance in the selection gains with exception in the characters plant height and grain mass of the main panicle. When the means of the families selected at the selection pressure of 10% and 20% are analyzed, there is a similarity between the two methods of conduction. We highlight the Modified SSD method that encompasses a larger number of genotypes with good agronomic performance and aggregate highlighted performance to various characters of interest. In this way the modifications made in the SSD method were beneficial to the breeding program and allowed the identification of a greater number of transgressive genotypes with the same crosses.

Although mango (Mangifera indica L.) has been studied for many years, numerous problems still elude researchers. The objectives of the current trials were to study the effects of some cultural practices (fruit thinning, panicle/ bud/ renewal/ post-harvest pruning) and chemicals (Corasil.E, potassium nitrate/urea, paclobutrazol) on various vegetative, floral, yield and quality parameters. The study meant to address problems of both South African and Ethiopian mango growers. The thinning (on ‘Sensation’) and pruning (on ‘Tommy Atkins’ and ‘Keitt’) experiments were conducted for two seasons (2001-2003) at Bavaria Fruit Estate in South Africa. Effects of Paclobutrazol and Potassium nitrate were studied on ‘Tommy Atkins’ during 2002-2003 season at Upper Awash Agro-industry Enterprise in Ethiopia. Complementary effects of paclobutrazol and potassium nitrate on floral induction were studied in growth chamber experiments at the experimental farm of University of Pretoria on ‘Tommy Atkins’ and ‘Keitt’ mango. Where fruit on ‘Sensation’ were thinned to one and two fruit per panicle, a significant increase was obtained for most of the fruit quantitative parameters. The treatments where one fruit and two fruit per panicle were retained and 50% panicles removed, produced a significant increase in size of the fruit, fruit qualitative parameters and fruit retention percentage. Corasil.E produced very small sized fruit with a considerable percentage of “mules” (fruit without seed). Trees subjected to severe thinning intensities showed earlier revival of starch reserves and better vegetative growth. Applications of paclobutrazol (1- (4-chlorophenyl) –4,4-dimethyl-2- (1,2,4- triazol-1-yl) pentan-3-ol) at rates of 5.50 and 8.25 g a.i. per tree, both as a soil drench and spray applications, on ‘Tommy Atkins’ mango were effective in suppressing vegetative growth as compared to the control. Consequently, the trees from these treatments had higher total non-structural carbohydrate in their shoots before flowering which led to higher results of percentages of shoots flowering, number of panicles produced, percentages of hermaphrodite flowers, yield and quality of the fruit. Trees that received panicle pruning (during full bloom) treatment at the point of apical bud attachment, were observed to be induced for synchronized re-flowering and also attained more fruit per panicle. On the other hand, trees on which renewal pruning (early in the season) and post-harvest pruning (especially for early cultivars) treatments were applied, have been observed for the development of an adequate number of productive inflorescences. Post-harvest pruning treatments also resulted in greater vegetative growth on both cultivars. The responses to pruning treatments were greater especially in ‘Tommy Atkins’ than ‘Keitt’. The trend for the interaction of duration and chemicals in Tommy Atkins and Keitt mango cultivars revealed the possible floral induction complementary effect of PBZ after the trees were induced only for 15 days at 10/15 oC temperature. Higher potassium nitrate concentrations especially in combination with urea (5 litre solution of 4% KNO3+0.5 g urea tree-1 and 5 litres of 4% KNO3+1 g urea tree-1 ) produced higher results for most of the flowering and yield parameters in ‘Tommy Atkins’. / Thesis (DPhil (Horticulture))--University of Pretoria, 2006. / Plant Production and Soil Science / unrestricted

Strategies to improve stem yield and juice quality in sweet sorghum were investigated in this study. Seed quality of sixty five accessions (landraces) from Botswana was investigated. Standard germination tests revealed that only 66% of the accessions had germination percentages in excess of 85%. The Accelerated Ageing test showed that only 50%of the 26 accessions had germination percentages above 80%. The results indicated that Botswana sweet sorghum seed quality is generally poor. Seed development and maturity observations demonstrated that maximum seed quality occurred 14 to 17 days after mass maturity (physiological maturity) and this coincided with maximum seed germination. These results suggest that harvesting sweet sorghum seed prior to mass maturity can lower seed quality. Farmers should, therefore be advised to select plants intended for seed harvesting and allow them to mature properly before the seeds are harvested. Differences in seed colour, shape and compactness of the inflorescences were observed amongst the 65 landraces collected from farmers in Botswana. Ten landraces were characterised and from the results it was evident that there was a range of genetic diversity which can be utilized in the improvement of the crop. Large panicles were characteristic of most sweet sorghum landraces, the effect of tiller, panicle and floret removal on juice quality was consequently studied. Removal of panicles and florets significantly improved juice quality whilst removal of tillers did not. Selection and breeding of genotypes with small panicles and male sterile varieties may improve juice quality and should be investigated. Effect of planting date, spacing and nitrogen were investigated. Early planting (October) resulted in increased stem yields but reduced juice quality. A 30 cm intra-row spacing resulted in high stem yields per plant and good juice quality. Nitrogen fertilisation increased stem yield and improved juice quality. On the bases of the results obtained from this study, early planting (October), application of 60 kg N ha-¹, and 30 cm intra-row spacing could be recommended for sweet sorghum production in pure stands. In pure stands yields of more than 37 000 stems (per hectare) of good quality can be attained. These could be sold at an estimated price of P2.00 (R2.25) per stem indicating the potential of sweet sorghum as a cash crop. However, its economic viability depends on the price elasticity in the supply - demand function. / Dissertation (PHD)--University of Pretoria, 2003. / Plant Production and Soil Science / unrestricted

LFY of Arabidopsis is a member of a unique plant specific transcription factor family. It is involved in giving meristem a determinate floral fate by the activation of floral organ identity genes and preventing inflorescence meristem identity. RFL is a homolog of FLO/LFY in rice. Studies from our lab on rice RFL, based on the effects of knockdown or overexpression, showed its major functions are in timing the conversion of SAM to IM and to prevent the premature conversion of branch meristem to spikelets. Additionally roles in vegetative axillary meristem specification have been also been identified in laboratory. Here, we attempt to delineate molecular pathways directly regulated by RFL as a transcription factor controlling inflorescence and floral development in rice. Part I: Identification of global target genes bound by RFL in developing rice inflorescences We carried out ChIP sequencing of the DNA bound by RFL in panicles (01.-0.3cm stage) using anti-RFL antibody. DNA sequences in one library pool were analyses by the MACS algorithm (FDR<0.01), to find 8000 binding sites while the SPP algorithm identified 5000 enriched peaks. These mapped to 2500 or 2800 gene-associated loci respectively, 617 of which were common loci to both pipelines. Several RFL bound gene loci were homologs of Arabidopsis thaliana LFY gene targets. Such gene targets underscore conserved downstream targets for LFY-proteins in evolutionarily very distinct species. AtLFY is known to bind variants of CCANT/G cis element classified as primary, inflorescence or seedling type. We scanned for these three types of cis elements at 123 RFL bound genes with likely functions in flowering. For a few of these 123 rice loci we find one of these cis motifs (p-value<0.001) in RFL bound ChIP-seq data. To validate these targets of RFL, we adopted in vitro DNA-protein binding assays with bacterially purified RFL protein. We confirm RFL target interactions with some genes implicated in flowering time, others in photoperiod triggered flowering, circadian rhythm, gibberellin hormone pathway, inflorescence development and branching. The in vitro experiments hint different RFL-DNA binding properties as compared to Arabidopsis LFY. We report binding to sequences at rice gene loci that are unique targets. Part II: Pathways regulated by RFL for reproductive transition and panicle development To co-relate DNA binding of RFL to target loci with changes in their gene expression, expression studies were taken up for selected set of genes implicated in rice flowering transition and panicle architecture. To study in planta and tissue specific gene regulation by RFL we raised RFL dsRNAi transgenics. Comparative transcript analysis in these RFL partial knockdown lines and matched wild type tissues reveal that RFL is an activator for some genes and repressor for other gene targets. We also examined if the gene expression effects of RFL knockdown can be reversed by induced complementation with an RFL-GR protein. We raised transgenics plants with a T-DNA ubi:RFL-GR, 35S CaMV:amiR RFL for these experiments. In planta target gene transcript levels were assessed in various conditions conditions. These studies validate rice RFL as an activator of some panicle architecture genes. Part III: Analysis of endogenous RFL protein in WT rice tissues Studies in Arabidopsis and in petunia with LFY and AFL, respectively, implicate these some abnormal mobility as compared to their predicted molecular weight when overexpressed. We studied endogenous RFL protein abundance in planta, adopting western analysis with anti-RFL antibody. We consistently identify two prominent cross reacting bands in different tissues which can be also be pulled-down from whole nuclear extracts of panicle and axillary meristem tissues. We speculate on likely modifications and possible functions for the same.