Number Of Basal Tillers Research Articles

Canopy leaf area and leaf mass in the upper stratum of Urochloa hybrid ‘Mavuno’ grass subjected to nitrogen fertilisation

AbstractNitrogen (N) inputs are recognised to maximise herbage mass (HM) in tropical perennial grasses, whereas less is clear on their impact on HM distribution and the effects on leaf mass (LM) and leaf area index (LAI) in the upper stratum. This 2 year study, carried out in Pirassununga, Brazil, assessed the HM distribution in the upper (>20 cm) and lower (<20 cm) strata in Urochloa hybrid ‘Mavuno’ grass maintained under similar pre‐ and post‐cutting canopy heights with contrasting N fertilisation rates applied after each cutting (no‐nitrogen, 15, 30, and 45 kg N ha−1). The relevance of specific leaf area (SLA), leaf N concentration (NLeaf), tiller weight (TW) and population density to the LM and LAI of the upper stratum were also examined. Mavuno grass expressed a stable HM < 20 cm (59%–71% during Year I and 66%–80% for Year II), and apparent N fertilisation impacts on HM > 20 cm were verified at specific regrowth cycles during Year II. Mavuno grass pastures expressed plasticity for adjustments on leaf, tiller and population attributes, which were modulated by both climatic conditions and N fertilisation. Under favourable growth conditions during Year I, fertilised pastures were able to sustain higher NLeaf and SLA but associated with lower TW, resulting in maximisation of LAI but not in LM in the upper stratum. During Year II, fertilised pastures expressed higher NLeaf, SLA, number of basal tillers, despite the lowest TW, which resulted in higher LAI and LM in the upper stratum compared with non‐fertilised pastures. Our results highlighted that adjustments on leaf and population attributes within the canopy were driven to maximise the upper stratum LAI, being positively affected by N fertilisation.

Assessment of variability in sorghum [Sorghum bicolor (L.) Moench] germplasm for agro-morphological traits

Sorghum [Sorghum bicolor (L.) Moench] is an important staple food crop of the semi-arid tropics. Phenotypic characterization of conserved gene bank accessions is necessary for their effective utilization for crop improvement. In this study, a total of 2834 accessions of sorghum were characterized during 2018-19 and the data were subjected to ANOVA, Pearson’s correlation analysis, and Shannon’s diversity index analysis. Shannon diversity index calculated indicated ear head shape to be the most diverse (H’=1.36). Several trait-specific accessions for early flowering (EC0524806, 57 days), high yield (IC0355254, 245.3 g/plan) etc. were identified. Pearson correlation analysis indicated that grain yield was positively influenced by the traits like ear head width (r=0.14), plant height (r=0.1), number of basal tillers (r= 0.07), and 100seed weight (r= 0.09). The trait-specific germplasm accessions identified in the study could be used as trait-specific donors by breeders for sorghum crop improvement. Keywords: Sorghum, Shannon Diversity, Correlation

Genetic variability of early flowering and yield contributing traits in Barnyard Millet [Echinochloa frumentacea (Roxb). Link] grown at different altitudes

Barnyard millet is an important up surging minor millet in Asia countries for food and nutritional security. Being a minorcrop, the genetics and inheritance of the traits need to understand, for effective utilization in the crop improvementprogrammes. Here, we investigated the genetic background and inheritance of different traits in barnyard millet genotypes.Forty germplasm accessions were evaluated in different ecological environments of southern India for 17 quantitative traits.Genetic variability analysis using GENSTAT and the pooled REML mean data results revealed that Phenotypic Co-efficientof Variation (PCV) was greater than the Genotypic Co-efficient of Variation (GCV) over the diverged ecological locationsindicating the existence of environmental influence on all the biometric traits studied. In the Western Ghats region (E1),high heritability coupled with high genetic advance was exhibited for traits like days to flowering, plant height, days tomaturity, number of nodes, length of nodes, number of basal tillers, stem diameter, flag leaf length, flag leaf width,inflorescence length, inflorescence width, length of peduncle, number of racemes, single ear head weight and grain yield perplant. Traits like thousand grain weight expressed moderate genetic advance with high heritability while, length of lowerracemes expressed moderate heritability with high genetic advance. Similarly, high heritability coupled with high geneticadvance was recorded for all the characters in valley region (E2) except thousand grain weight that showed high heritabilitybut moderate genetic advance. In contrast, in the area of plains (E3), all the traits exhibited high heritability coupled withhigh genetic advance. Since, majority of the traits have shown high heritability with high genetic advance, selection mightbe effective in these traits irrespective of the environment.

Genetic variability and association analysis in the segregating population of extra early barnyard millet [Echinochloa frumentaceae (Roxb.) Link] involved crosses

An investigation was conducted to evaluate the F2 population of two crosses of barnyard millet viz., cross I, ACM-15-343 X IEC 82 and cross II, Co (Kv) 2 X IEC 107 for extra earliness. Genetic variability and association analyses were carried out for sixteen biometrical traits. In both the crosses, high PCV and GCV was observed for the width of flag leaf, length of a lower raceme, number of racemes and grain yield per plant. Low PCV and GCV was observed for days to maturity. The minimum difference between PCV and GCV was observed for all the traits in both crosses, indicating the negligible effect of environment on the expression of the characters. Moderate to high heritability with moderate to high genetic advance in all the traits revealed the predominance of additive gene action. A positive significant correlation was noted for grain yield with plant height, days to flowering, days to maturity, the number and length of nodes, the number of basal tillers, stem diameter and single ear head weight. Path analysis disclosed a high positive direct effect of the number of basal tillers and single ear head weight on yield. These results together help in the selection of superior segregants based on the number of basal tillers and single ear head weight in forwarding them to successive generations. Key words: Barnyard millet, F2, Variability, Association analysis

Effect of Selected Weed Management Practices on the Growth and Yield Components of Finger Millet (Eleusine coracana) in Western Region of Kenya

Finger millet (Elusine coracana) accounts for 8% of the total area and 11% of the millet production worldwide. It is grown on over 4 million ha globally, mainly for food purposes. Millions of people in the dry lands of Central and East Africa, and South of India depend on finger millet as an important source of food to them (CGIAR, 2001). Finger millet is one of the most neglected and underutilized crops. Additionally, the crop has received limited research attention compared to wheat, rice, and maize (FAO, 2011). Therefore, production challenges such as those caused by weeds like goose grass Elusine indica remain at large. Manual weeding is the commonly employed weed control method in finger millet production, but is expensive and labour intensive. The current study was set to evaluate the influence of weed management practices on finger millet growth and yield components. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replicates. The plots measured 2 by 2m with a border width of 1m. The treatments included Pendimethalin, Dimethyl amine, Metolachlor, Metribuzin, Atrazine (at three rates each 1.0, 1.5 and 2.0 l/ha), No weeding and Hand weeding. Data was collected on the number of weed species, weed biomass, number of basal tillers, herbicide phytotoxicity, weed and crop heights, number of panicles, weight of panicles, weight of un-threshed and threshed grains and 1000 grain weight. Data was analyzed using one-way ANOVA using GenStat version 15.1. Application of Pendimethalin at 1.5 and 2.0 L/ha Active Ingredient (AI), resulted in weed optimal control and least phytotoxicity. Results also indicated that the height of finger millet was significantly (p<0.001) higher where the herbicides were applied. Lower weed biomass was also positively correlated with higher crop height, more panicles, high unthreshed and threshed weights and a 1000 grain weight. Application of 2,4D at rates of 1.5L and 2.0L resulted in significantly taller plants 33.00 cm, than the other weed management methods. Finger millet under Pendimethalin 1.5 L gave the highest number of 86 panicles while Atrazine 2.0L and Pendimethalin1.5L methods of weed control, had significantly higher weight compared to all the other treatments. The 1000 seed mass across the treatments averaged 2.31 g while the on the untreated treatments had an average of 1.54 g. Weed control using pre emergence herbicides significantly (p<0.001) increased the yields of finger millet.

Structure of differed Marandu palisade grass with variables nitrogen doses and heights

This study aims to evaluate the effects of height (15 and 30 cm)and nitrogen dose (N, 40, 80, and 120 kg ha-1) at the beginning of thestockpiling period on the structural characteristics of the Urochloabrizantha cv. Marandu (Marandu palisade grass) during winter. Thefalling index of the plant did not vary with the factors under scrutiny(P>0,10). The number of basal tillers was higher (P<0,10) in the 15-cmdeferred canopy than in the 30-cm canopy only when the highest N dosewas used. Under conditions of application of 0 or 80 kg ha-1 of N, the 30-cmstockpiled canopies showed a higher (P<0,10) forage mass than the 15-cmones. Associated with reduced canopy height at the beginning ofstockpiling period, nitrogen fertilization improves the morphologicalcomposition of Marandu palisade grass. To maximize the forage mass inthe dry season, the canopies of Marandu palisade grass can be deferredeither at 15 cm (fertilized with about 100 kg ha-1 of N) or at 30 cm (with nonitrogen fertilization) at the beginning of the stockpiling period.

ζ-Carotene Isomerase Suppresses Tillering in Rice through the Coordinated Biosynthesis of Strigolactone and Abscisic Acid

Rice tillering is an important agronomic trait affecting grain yield. Here, we identified a high-tillering mutant tillering20 (t20), which could be restored to the wild type by treatment with the strigolactone (SL) analog rac-GR24. T20 encodes a chloroplast ζ-carotene isomerase (Z-ISO), which is involved in the biosynthesis of carotenoids and their metabolites, SL and abscisic acid (ABA). The t20 mutant has reduced SL and ABA, raising the question of how SL and ABA biosynthesis is coordinated, and whether they have overlapping functions in tillering. We discovered that rac-GR24 stimulated T20 expression and enhanced all-trans-β-carotene biosynthesis. Importantly, rac-GR24 also stimulated expression of Oryza sativa 9-CIS-EPOXYCAROTENOID DIOXYGENASE 1 (OsNCED1) through induction of Oryza sativa HOMEOBOX12 (OsHOX12), promoting ABA biosynthesis in shoot base. On the other hand, ABA treatment significantly repressed SL biosynthesis and the ABA biosynthetic mutants displayed elevated SL biosynthesis. ABA treatment reduced the number of basal tillers in both t20 and wild-type plants. Furthermore, while ABA-deficient mutants aba1 and aba2 had the same number of basal tillers as wild type, they had more unproductive upper tillers at maturity. This work demonstrates complex interactions in the biosynthesis of carotenoid, SLs and ABA, and reveals a role for ABA in the regulation of rice tillering.

Diversity study using principal component analysis in barnyard millet (Echinochloa frumentacea (Roxb.) Link)

Among nutri-cereals, now-a-days, barnyard millet getting popular among the public for its rich nutritional and cooking qualities. A total of forty genotypes were evaluated in three different environments to study the genetic diversity using Principal Component Analysis. Foremost three components contributed 85.65% of the total multivariable differences. Germplasm projection delivered four main groups on first two canonical components. Genotypes splitting were on the basis of trait performance. Majority of the traits had explained low to moderate values with negative loadings to PC1, PC2 and PC3 except few traits like thousand grain weight and number of basal tillers, which had positive loadings with high values. Loadings bi-plots of PC1-PC2 and PC1-PC3, classified the groups into two major categories, consisting of late matured -high yielding genotypes on left side and early matured -low to medium yielding genotypes on right side of scattering.

Genetic variability and association analysis in barnyard millet mutants

The present study was carried out using 40 mutants along with two check varieties CO(Kv)2 and MDU1 during Kharif 2019. Sixteen characters were studied and out of which only 11 traits showed significant variation. Correlation and path analysis were done for 11 traits viz., number of basal tillers, days to fifty percent flowering, flag leaf length, panicle length, plant height, number of raceme, number of productive tillers, number of leaves in main tiller, average leaves in side tiller, single ear head weight and single plant yield. Among the eleven biometrical traits, high heritability was recorded by traits such as number of basal tillers, days to fifty percent flowering, flag leaf length, plant height, number of racemes, number of productive tillers, number of leaves in main tiller, single ear head weight and single plant yield. Correlation studies showed that number of productive tillers, single ear head weight and plant height possess significant positive correlation with yield at both genotypic and phenotypic level. Path analysis showed that traits like number of basal tillers, single ear head weight and panicle length had high direct effect on yield. Thus, selection of these traits would be rewarding for yield improvement in barnyard millet.

Morphogenetic and structural characteristics of Urochloa species under inoculation with plant-growth-promoting bacteria and nitrogen fertilisation

Ineffective management of pastures still constitutes the main problem in the Brazilian livestock industry, in which recovery of soil fertility is a determinant for soil restoration. In this context and in combination with the adoption of sustainable technologies, the use of plant-growth-promoting bacteria (PGPB) may represent an alternative to the use of chemical fertilisers that would reduce costs and environmental impacts. In this study, morphogenetic and structural characteristics were evaluated in three Urochloa (syn. Brachiaria) varieties. Urochloa is a genus that is present in the most degraded pastures in Brazil. The three varieties were inoculated with five PGPB (Azospirillum brasilense Ab-V5 and Ab-V6, Pseudomonas fluorescens CCTB 03 and ET76, and Pantoea ananatis AMG521) and treated with different doses of nitrogen (N) fertiliser (0, 50 and 100 kg N ha–1) in pots filled with sandy soil under greenhouse conditions. In general, for Marandu grass U. brizantha cvv. BRS Paiaguás and Xaraés, the best performances for leaf and stem elongation rates and number of basal tillers were obtained with strains CCTB 03 and AMG521. For U. ruziziensis, the best performance in the duration and rate of renewal of leaves and leaf senescence was observed with strains AMG521, Ab-V5 and Ab-V6. This result indicated the specificity of the effects of bacterial strains on different genotypes of Urochloa. Differences in the interactions between PGPB and N fertilisation were also verified. In U. brizantha, interaction effects were additive, whereas in U. ruziziensis, they were competitive. The results indicate the feasibility of inoculation of Urochloa with elite strains of PGPB that positively affect the production of forage biomass and allow reductions in N fertiliser usage.

Phenotypic Diversity and Molecular diversity of Finger Millet Composite Collection and Identification of Trait Specific Germplasm for Use in Crop Improvement

A composite collection of finger millet consisting of 1000 accessions representing the diversity of the entire germplasm at ICRISAT gene bank was developed, including 622 accessions of ICRISAT core collection. Phenotyping of the composite collection for 15 quantitative traits and 20 SSR markers genotyping data resulted in the identification of promising traitspecific accessions. Principal component analysis with seven components indicated relative importance of the traits (days to 50 % flowering, plant height, peduncle length, ear head length, and panicle exertion) to total divergence. Clustering analysis grouped biological races into three clusters wherein cultivated races vulgaris, plana, elongata, and compacta were grouped in Cluster I and wild races spontanea in Cluster II and africana in Cluster III. Accessions were identified as useful for important traits such as early flowering (34), high grain yield (38), fodder yield (19); more fingers (29); basal tiller number (25) and ear head length (28).

Tillering dynamics of Alexandergrass pasture under nitrogen fertilization

ABSTRACT This study was carried out to evaluate the effect of nitrogen fertilization on tillering dynamics of Alexandergrass (Urochloa plantaginea (Link) Hitch) grazed by beef heifers in a rotational stocking grazing method. The experiment was conducted in a completely randomized design following a repeated measure arrangement, three levels of nitrogen (Zero, 150 and 300kg ha-1) and two area repetition. The classification of tillers into categories (basal and axillary) showed a greater number of basal tillers, due to their higher appearance rate, in the absence of nitrogen fertilization. Nitrogen fertilization promoted higher axillary tiller density. The use of nitrogen promotes the renewal of axillary tillers of Alexandergrass, without compromising the stability of the tiller population.

CARACTERÍSTICAS ESTRUTURAIS E PRODUTIVAS EM HÍBRIDOS INTRAESPECÍFICOS E INTERESPECÍFICOS DE CAPIM-ELEFANTE

Resumo Objetivou-se avaliar a estrutura e a produção de forragem em híbridos de capim-elefante manejados sob corte. Utilizaram-se como tratamentos 24 clones de capim-elefante provenientes da Embrapa Gado de Leite e o Cameroom como testemunha. Os capins foram cortados rentes ao solo, a cada 60 dias. Os parâmetros avaliados foram: produção e teor de matéria seca, número de perfilhos basais, número de folhas por perfilho, altura da planta, diâmetro do colmo. A maior altura das plantas foi observada no clone CNPGL 00-103-1. O grupo com maior número de perfilhos teve três clones e média de 39,38 perfilhos m-2. No grupo dos clones CNPGL 00-103-1, CNPGL 93-25-3, CNPGL 00-16-1 e CNPGL 00-90-3 foram observados os maiores teores de matéria seca (22,7% de MS). As maiores massas de forragem, de lâmina foliar e de colmo foram observadas no clone CNPGL 00-214, 15852 e 6195 kg ha-1 de MS respectivamente. A maior relação lâmina foliar/colmo foi do clone CNPGL 00-201-1 e apenas neste a massa de lâmina foliar foi superior à de colmo. O clone CNPGL 00-214 mostrou-se mais produtivo, com alta capacidade de perfilhamento e de acúmulo de forragem.

ESTRUTURA DO DOSSEL E CARACTERÍSTICAS DE PERFILHOS EM PASTOS DE CAPIM-PIATÃ MANEJADOS COM DOSES DE NITROGÊNIO E PERÍODOS DE DIFERIMENTO VARIÁVEIS

Resumo Este trabalho foi desenvolvido de 25 de fevereiro a 01 de julho de 2012 para recomendar a(s) dose(s) de nitrogênio e o(s) período(s) de diferimento que resultam em pastos diferidos de Brachiaria brizantha cv. Piatã (capim-piatã) com características estruturais adequadas ao consumo animal. Foram avaliadas combinações entre períodos de diferimento e condições de adubação nitrogenada. Os períodos de diferimento foram longo (127 dias) e curto (79 dias). As doses de nitrogênio foram de 0, 40, 80 e 120 kg/ha. O delineamento experimental foi de blocos casualizados, com três repetições. O índice de área foliar (IAF) e a interceptação luminosa (IL) aumentaram com a aplicação de nitrogênio. Na ausência ou dose pequena de nitrogênio, o pasto diferido por curto período apresentou IAF e IL inferiores ao manejado com longo período de diferimento. A dose de nitrogênio só influenciou a densidade de perfilhos basais vegetativos. O menor período de diferimento resultou em maiores números de perfilhos basais e aéreos vegetativos, assim como número inferior de perfilho basal reprodutivo. O nitrogênio aumentou o comprimento da lâmina foliar e do colmo do perfilho vegetativo. Longo período de diferimento resultou em colmo e lâmina foliar mais compridos e maior número de folhas mortas. O capim-piatã pode ser diferido por 80 dias, com aplicação de 80 kg/ha de nitrogênio no início do período de diferimento.

Genetic variability studies for yield and yield components in kodo millet (Paspalum scrobiculatum L.)

The experimental material comprised of one hundred and three germplasm accessions of kodo millet (Paspalum scrobiculatum L.) were evaluated to assess the genetic variability, heritability and genetic advance for fifteen yield component traits. Analysis of variance revealed that there were significant differences among the accessions for all the traits studied. The coefficient of variation at phenotypic (PCV) and genotypic (GCV) levels were high for Zn content, grain yield per plant, Fe content, number of productive tillers and thumb length. Broad sense heritability ranged from 54.18 per cent for length of the longest raceme to 97.30 per cent for days to 50 per cent flowering. High heritability coupled with high genetic advance as per cent of mean was observed for plant height, number of basal tillers, number of productive tillers, flag leaf width, inflorescence length, thumb length, Zn content, Fe content and grain yield per plant which indicates that these traits are under the influence of additive gene effects and selection may be effective for these characters.

Genetic diversity and variability in Foxtail millet [Setaria italica (L.)] germplasm based on morphological traits

Fifty one accessions of foxtail millet (Setaria italica (L.) P. Beauv.), constituting a national elite germplasm collection were evaluated for morphological diversity based on nine quantitative traits viz., plant height, number of basal tillers, days to flowering, flag leaf length, flag leaf width, petiole length, inflorescence length, thousand seed weight and single plant yield. The traits showed a continuous distribution, however number of basal tillers, and single plant yield exhibited skewness in positive directions. Considerable variability was observed among the genotypes for all the traits. Among these, grain yield per plant exhibited the maximum variation with a CV of 22.5%, while days to fifty per cent flowering and plant height exhibited the least variation with a CV 7.2% and 9.3% respectively. PCA analysis revealed that the first four components in the PCA results contributed to a maximum of 70 per cent of the variability, the contributions from PC1, PC2, PC3 and PC4 being 30.1%, 14.2%, 13.8%, and 11.4%, respectively. The first two components were a measure of vegetative and inflorescence characters, while the third component was a measure of thousand seed weight. Cluster analysis based on the nine morphological traits assorted the 51 genotypes into four main clusters. Dendrogram based on hierarchal clustering grouped the genotypes based on their morphological traits, however the grouping of genotypes did not correspond with their geographic origin. Plant height, number of tillers, days to fifty per cent flowering, grain yield per plant, and 1000 seed weight were found to be the most important traits in distinguishing the major clusters of foxtail millet genotypes at the morphological level.

Barnyard millet global core collection evaluation in the submontane Himalayan region of India using multivariate analysis

Barnyard millet (Echinochloa spp.) is one of the most underresearched crops with respect to characterization of genetic resources and genetic enhancement. A total of 95 germplasm lines representing global collection were evaluated in two rainy seasons at Almora, Uttarakhand, India for qualitative and quantitative traits and the data were subjected to multivariate analysis. High variation was observed for days to maturity, five-ear grain weight, and yield components. The first three principal component axes explained 73% of the total multivariate variation. Three major groups were detected by projection of the accessions on the first two principal components. The separation of accessions was based mainly on trait morphology. Almost all Indian and origin-unknown accessions grouped together to form an Echinochloa frumentacea group. Japanese accessions grouped together except for a few outliers to form an Echinochloa esculenta group. The third group contained accessions from Russia, Japan, Cameroon, and Egypt. They formed a separate group on the scatterplot and represented accessions with lower values for all traits except basal tiller number. The interrelationships between the traits indicated that accessions with tall plants, long and broad leaves, longer inflorescences, and greater numbers of racemes should be given priority as donors or parents in varietal development initiatives. Cluster analysis identified two main clusters based on agro-morphological characters.

Morfogênese e fluxo de tecidos em capim Tanzânia sob diferentes ofertas de forragem

This study was conducted to identify effective strategies for grazing managing of Panicum maximum Jacq cv. Tanzania, under continuous stocking with variable stocking rate, based on assessments of their morphogenetic and structural characteristics. Four forage allowances: 3, 7, 11, and 15% BW were studied. A randomized block design, with three replicates was used, with split plot, where FA 4 as main plots and subplots were established cages. The number of basal tillers per cage protected and unprotected, both remaining as the new, decreased with FA. The unprotected tillers had higher numbers than cage protected. The weight of tillers and roots showed curvilinear response function in the FA. There was no effect of period at tillering (P> 0.05) of Tanzania grass. The total length of sheets, protected or not by exclusion cage and ligule height of tillers per cage had unprotected quadratic fit function OF. The ligule height protected tillers showed linear response function in the OF. The total number of leaves, expanded and expanding, tiller protected or not by exclusion cage, showed no differences between the FA and cage exclusion. The use of forage allowance of 11% of body weight for tanzania grass managed under continuous grazing and variable stocking rate, seems to be more sustainable.

Association mapping of agro-morphological characters among the global collection of finger millet genotypes using genomic SSR markers.

Identification of alleles responsible for various agro-morphological characters is a major concern to further improve the finger millet germplasm. Forty-six genomic SSRs were used for genetic analysis and population structure analysis of a global collection of 190 finger millet genotypes and fifteen agro-morphological characters were evaluated. The overall results showed that Asian genotypes were smaller in height, smaller flag leaf length, less basal tiller number, early flowering and early maturity nature, small ear head length, and smaller in length of longest finger. The 46 SSRs yielded 90 scorable alleles and the polymorphism information content values varied from 0.292 to 0.703 at an average of 0.442. The gene diversity was in the range of 0.355 to 0.750 with an average value of 0.528. The 46 genomic SSR loci grouped the 190 finger millet genotypes into two major clusters based on their geographical origin by the both phylogenetic clustering and population structure analysis by STRUCTURE software. Association mapping of QTLs for 15 agro-morphological characters with 46 genomic SSRs resulted in identification of five markers were linked to QTLs of four traits at a significant threshold (P) level of ≤ 0.01 and ≤ 0.001. The QTL for basal tiller number was strongly associated with the locus UGEP81 at a P value of 0.001 by explaining the phenotypic variance (R (2)) of 10.8%. The QTL for days to 50% flowering was linked by two SSR loci UGEP77 and UGEP90, explained 10 and 8.7% of R (2) respectively at a P value of 0.01. The SSR marker, FM9 found to have strong association to two agro-morphological traits, flag leaf width (P-0.001, R(2)-14.1 %) and plant height (P-0.001, R(2)-11.2%). The markers linked to the QTLs for above agro-morphological characters found in the present study can be further used for cloning of the full length gene, fine mapping and their further use in the marker assisted breeding programmes for introgression of alleles into locally well adapted germplasm.

Morphological changes and resource allocation of Zizania latifolia (Griseb.) Stapf in response to different submergence depth and duration

Plants around ponds, rivers and lakes are subjected to long-term partial or complete submergence. When they are flooded, water level affects the plants simultaneously with duration of submergence. Separate and interactive effects of water level and duration on the growth of the herbaceous perennial Zizania latifolia (Poaceae) were investigated by exposing the plants in greenhouse water tanks to submergence in different water depths and for different time-spans. The plants exhibited great shoot elongation upon submergence and prolonged flood duration, and the basal tiller number of the species decreased with higher water levels. Submergence treatment advanced the flowering date and increased the inflorescence number. Plant total biomass did not differ among all the treatments, while the root:shoot ratio decreased with increased water level, prolonged duration of submergence and their interaction. The high plasticity in morphology and shifts in reproductive strategy and biomass allocation enabled the Zizania plants to survive the compound effect of flooding height and duration. This may explain the occurrence of this species in habitats subjected to long-term flooding. The results obtained in this experiment will contribute to understanding the impact of flooding dynamics on plants and the ways of adaptation responses to prolonged waterlogging.