Day Of Anthesis Research Articles

Nectary ultrastructure of Cabomba caroliniana Gray (Cabombaceae)

Cabomba Aubl. is a genus considered as a potential genetic model for studies of early angiosperm evolution, accordingly, it is important to expand the knowledge of it. This paper reports the study of the anatomy and the ultrastructure of the nectary of Cabomba caroliniana Gray using bright-field microscope, scanning and transmission electron microscope in order to understand its secretion mechanism. C. caroliniana has protoginous flowers and the anthesis lasts two days. Nectaries of C. caroliniana are located in two basal lobes or yellow auricles of each white petal. Most nectar is observed in the area above the pronounced auricles. The secretion is released mainly by the four-cellular trichomes or hydropotens present in both nectary epidermis. The cellular ultrastructure indicates that the nectary is active during the two days of the anthesis. This agrees with the fact that in both anthesis days the fertile structures of the flower (first the stigmata and then the anthers) are disposed above the nectaries. The nectar secretion mechanism is discussed in relation to the present knowledge. The results of this study are related to what has been described for other basal angiosperms.

Genetics of Grain Yield and its Components in Wheat under Heat Stress

Heat stress is a matter of a great concern for the wheat crop. Heat stress usually either hastens crop development or shortens the grain filling duration, which severely reduces grain yield. Being a complex trait, understanding the genetics and gene interactions of stress tolerance are the two primary requirements for improving yield levels. Genetic analysis through generation mean analysis helps to find out the nature of gene actions involved in a concerned trait by providing an estimate of main gene effects (additive and dominance) along with their digenic interactions (additive × additive, additive × dominance, and dominance × dominance). In the present investigation, we elucidated the inheritance pattern of different yield contributing traits under heat stress using different cross combinations which could be helpful for selecting a suitable breeding strategy. Thus six generations of five crosses were sown normal (non-stress, TS) and late (heat stress, LS) in a randomized block design with three replications during two crop seasons. The model was not adequate for late sown conditions indicating the expression of epistatic genes under stress conditions. The traits i.e. Days to heading (DH), Days to anthesis (DA), Days to maturity (DM), Grain filling duration (GFD), Grain yield (GY), Thousand grain weight (TGW), Grain weight per spike (GWS) and Heat susceptibility index (HSI) under heat stress conditions were found under the control of additive gene action with dominance × dominance interaction, additive gene action with additive × dominance epistatic effect, dominance gene action with additive × additive interaction effect, additive and dominance gene action with dominance × dominance interaction effect, additive gene action with additive × dominance epistatic effect, additive gene action with additive × additive interaction effect and dominance gene action with additive × additive interaction effect, respectively.

Four Parent Maize (FPM) Population: Effects of Mating Designs on Linkage Disequilibrium and Mapping Quantitative Traits.

Multiparent advanced generation inter-cross (MAGIC) populations can provide improved genetic mapping resolution by increasing allelic diversity and effective recombination. The Four Parent Maize (FPM; L.) population implemented five different mating designs used in MAGIC and bi-parental populations to compare empirical effects on genetic resolution and power of quantitative trait locus (QTL) detection; the combined population here comprised of 1149 individuals with 118,509 genetic markers. Measurements were recorded for plant height (PH), ear height (EH), days to anthesis (DTA) and silking (DTS) in seven environments, spanning three years. Linkage disequilibrium (LD) analysis of subpopulations indicated MAGIC population designs should incorporate generations of intermating to overcome initial LD increase caused by population admixture in a non-intermated four parent population (4way0sib). A 3- to 4-fold increase in genetic resolution (<0.8) and a 2.5-fold decrease in the extent of LD decay (<0.2) compared to the biparental populations was found for the four parent cross at the third generation of intermating (4way3sib). Power of QTL detection was affected to a greater extent by sample size rather than by mating designs. The FPM power simulations indicated that MAGIC populations have the ability to meet or exceed the mapping power of nested association panels with fewer individuals and diversity inputs. Using association mapping software we identified 2, 5, 7, and 6 QTL for PH, EH, DTA, and DTS, respectively. The FPM population is a valuable resource for quantifying empirical improvements of parent number, intermating, and the number of progeny for QTL linkage mapping.

Reproductive biology of Oreocereus fossulatus (Cactaceae), a long‐lived columnar cactus endemic to the tropical Andes

AbstractThe geographic dichotomy hypothesis suggests that columnar cacti inhabiting the tropics depend on flower visitors (birds and bats) for their pollination, showing highly specialized animal‐pollinated systems. This pattern has been demonstrated for the northern hemisphere; however, our knowledge of the species of columnar cacti growing in the southern tropics is still scarce. In this study, we studied the reproductive biology of Oreocereus fossulatus (Cactaceae, Tribe Trichocereae), an endemic, columnar cactus of the tropical Andes, to determine if its pollination system tends to be more generalized (mixed systems of autogamy and xenogamy) than specialized (xenogamy) as a consequence of the geographic position of where it lives. Observations of the frequency of visits showed that Patagona gigas (Trochillidae) is its main pollinator. It visits the flowers when they are open, coinciding with the periods of greater floral reward (dusk and dawn of the first day of anthesis). The treatments of autogamy, xenogamy and geitonogamy produced fruits, showing that O. fossulatus exhibits a generalized pollination system, in the same way as its congeneric species O. celsianus, which is distributed farther south in the Prepuna biogeographical region. Our results suggest that species partially specializing in pollination by hummingbirds and, besides, capable of autopollination, could be common in the tropical and subtropical Andes, probably as a response to the unpredictable environments present in their ecosystems.

Essential oil production of Murraya paniculata (L.) Jack at different harvest times

Murraya paniculata (L.) Jack has a fragrant flower, from which the fragrance is due to the essential oil. The study aimed to investigate the production of essential oil and its chemical compounds at different harvest times. The research was conducted at an organic experimental farm, Bogor Agricultural University, Bogor, Indonesia (6°30’-6°45’ S, 106°30’-106°45’ E) from October 2016 to February 2017 using randomized complete block design. The experiment consisted of one factor, namely the harvest times, comprised of harvest at 05.00-07.00 and 07.00-09.00 a.m. M. paniculata flowers were collected at three different flower ages, comprised of two days before anthesis, one day before anthesis and the day of anthesis (blooming). The different flower ages indicated by the flower size. Ethanol extraction method was used to extract the essential oil of the flowers from different harvesting times and then chemical compounds were analyzed by Gas Chromatography-Mass Spectrometry. The result showed that flower number and weight were not affected by harvesting times. The flower collected on the day of anthesis had the highest flower number and weight. Harvesting flowers at anthesis can be done at 05.00-09.00 a.m. The highest quantity and quality of essential oils were obtained by harvesting the flowers at anthesis. β-methylesculetin and murralongin were the primary compounds in M. paniculata flowers that harvested at 05.00-09.00 a.m.

Elevated temperature and moisture deficit stress impact on phenology, physiology and yield responses of hybrid maize

A field experiment was conducted with maize (Zea mays L.) hybrid DHM-117 under elevated temperature and moisture deficit stress to assess the phenology, physiology, biomass and yield responses. The elevated canopy temperature (ET) was maintained as 3°C above ambient canopy temperature (AT) in Free Air Temperature Elevation (FATE) facility and water deficit stress (WD) was imposed at initiation of tasseling stage in an open plot experiment to assess the impact of these two abiotic stresses. As compared with ambient control, the phenology of flowering with the ET was early as 3 days for anthesis, 1 day for silking and this increased 4 days for anthesis silking interval (ASI), while with WD, anthesis was delayed by 2 days, silking by 3 days and ASI increased by 3 days. It was observed that both ET and WD significantly decreased photosynthetic rate (32%, 24%), stomatal conductance (45%, 28%), transpiration rate (36%, 44%) while increased WUE (6%, 38%). It is interesting to record that there was reduction in total biomass (11%, 13%) especially reproductive biomass (44%, 31%) with both ET and WD while vegetative biomass was improved (27%, 8%) revealing that reproductive components are effected with these abiotic stresses thereby decreased HI (42%, 36%). The impact of ET was more on seed set than seed filling as the reduction in test weight (8%) was higher than at WD (4%).

Diurnal regulation of the floral scent emission by light and circadian rhythm in the Phalaenopsis orchids

BackgroundPhalaenopsis bellina and its closely related species, P. violacea, emit linalool, geraniol and their derivatives as the predominant monoterpenes at the full-bloom stages. Geranyl diphosphate synthase (PbGDPS) is the key enzyme that converts precursors for monoterpene biosynthesis. Besides the monoterpenes being synthesized in concert with floral development stages, we noticed that the scent emission of P. bellina and P. violacea was detected mainly in the daytime.ResultsThe monoterpenes of P. violacea flowers displayed a diurnal emission pattern, which was regulated by an internal oscillator in the treatment of constant light. In contrast, constant dark diminished the scent emission levels, indicating that light also affects monoterpene emission in P. violacea. Further treating P. violacea with various light wavelengths showed that the monoterpene emission was greatest in white light condition. Other Phalaenopsis hybrids, including P. I-Hsin Venus ‘KHM2212’ and P. Meidarland Bellina Age ‘LM128’, responded differently to various light wavelengths but most of them still showed the highest scent emission under the whole spectra of light. A great number of light-responsive, HY5-interacting, and circadian-responsive elements was enriched on the promoters of both structural genes and transcription factors for monoterpene biosynthesis. Furthermore, several putative genes encoding components involved in light and circadian signaling pathways were also identified in the transcriptome of P. bellina flowers at consecutive stages (from the anthesis day to day 7 post anthesis).ConclusionsTaken together, both circadian clock and light factors had positive effects on orchid floral scent emission, and the regulation resided on the control of both structural genes and transcription factors for monoterpene biosynthesis.

Character association and path co-efficient analysis in wheat (Triticum aestivum L.)

The experiment was carried out with 50 wheat lines to study their mean, range, cv (%), correlation co- efficient, and path co- efficient considering 14 different morphological characters at the experimental field of Regional Wheat Research Centre (RWRC), Bangladesh Agricultural Research Institute (BARI), Gazipur during December 2010 to April 2011. Significant variation was observed among the genotypes for all characters studied. In general, genotypic correlations were higher than the phenotypic correlations. It indicates that there was an inherent association among them which was adversely influenced by the environment. The correlation coefficients showed that, seed yield was negatively and significantly correlated with days to heading (DTH), plant height (PHT), days to anthesis (DTA), days to physiological maturity (DPM), and canopy temperature at anthesis stage (CTanth.) but only negatively correlated with canopy temperature at vegetative stage (CTveg.), canopy temperature at grain filling stage (CTgf.), spikelets per spike both genotypically and phenotypically and grain per spike showed genotypically negative correlation. Path analysis showed that plant height (PHT), days to physiological maturity (DPM), canopy temperature at grain filling stage (CTgf.), and thousand grain weight (TGW) influenced seed yield directly in positive direction but days to heading (DTH), days to anthesis (DTA), grain filling duration (GFD), grain filling rate (GFR), Chlorophyll content at anthesis stage (CHLA), canopy temperature at vegetative stage (CTveg.), canopy temperature at anthesis stage (CTanth.), spikelets per spike, and grains per spike had negative direct effect on seed yield. Considering analytical findings of correlation co-efficient, path co-efficient analysis and field performance, the genotypes G 3, G 10, G 11, G 12, G13, G 21, G 29, G 35, G 38, G 40, G 46 and G 48 were found suitable for future breeding programme.Bangladesh J. Agril. Res. 42(3): 571-588, September 2017

Carbohydrate metabolism in the subtending leaf cross-acclimates to waterlogging and elevated temperature stress and influences boll biomass in cotton (Gossypium hirsutum).

Short-term waterlogging and chronic elevated temperature occur concomitantly in the cotton (Gossypium hirsutum) growing season. While previous research about co-occurring waterlogging and elevated temperature has focused primarily on cotton fiber, no studies have investigated carbohydrate metabolism of the subtending leaf (a major source leaf for boll development) cross-acclimation to aforementioned stressors. To address this, plants were exposed to ambient (31.6/26.5°C) and elevated (34.1/29.0°C) temperatures during the whole flowering and boll formation stage, and waterlogging (0, 3, 6 days) beginning on the day of anthesis. Both waterlogging and high temperature limited boll biomass (reduced by 1.19-32.14%), but effects of different durations of waterlogging coupled with elevated temperature on carbohydrate metabolism in the subtending leaf were quite different. The 6-day waterlogging combined with elevated temperature had the most negative impact on net photosynthetic rate (Pn) and carbohydrate metabolism of any treatment, leading to upregulated GhSusA and GhSusC expression and enhanced sucrose synthase (SuSy, EC 2.4.1.13) activity for sucrose degradation. A prior exposure to waterlogging for 3 days improved subtending leaf performance under elevated temperature. Pn, sucrose concentrations, Rubisco (EC 4.1.1.39) activity, and cytosolic fructose-1,6-bisphosphatase (cy-FBPase, EC 3.1.3.11) activity in the subtending leaf significantly increased, while SuSy activity decreased under 3 days waterlogging and elevated temperature combined relative to elevated temperature alone. Thus, we concluded that previous exposure to a brief (3 days) waterlogging stress improved sucrose composition and accumulation cross-acclimation to high temperature later in development not only by promoting leaf photosynthesis but also inhibiting sucrose degradation.

Pollen Viability of Aeschynanthus tricolor Hook.

Aeschynanthus (Gesneriaceae) is climbing or trailing epiphytes from the tropical forests of South-East Asia. Several species are widely cultivated for their attractive flowers, which usually scarlet with long corolla tubes and probably bird pollinated.This study was carried out on Aeschynanthus tricolor Hook. to determine in vitro germinability of (1) pollen collected from flowers at anthesis, on the day before anthesis, or up to five days after anthesis and (2) pollen collected on the day of anthesis and then stored at -20oC for 127 days. Germinability tests were carried out on pollen grains after stored for four hours in 10% sucrose solution. The highest in vitro germination percentage observed was pollen collected on the day of anthesis (96.3%) and the lowest was pollen collected on the fifth day after anthesis (5.6%). The germination percentage of pollen after stored at -20oC was 98% at beginning and 22% after 127 days. From this research we can conclude that pollen of A. tricolor can be successfully collected and then stored for some time, will be practical benefit for plant breeding and conservation purposes.

In vitro pollen viability of maize cultivars at different times of collection

ABSTRACT: In the present study, we aimed to assess the in vitro viability of pollen grains from maize cultivars collected at different times and days in the field. Four cultivars (Sol da Manhã, XB 6012, XB 8010, and BRS 2020) were evaluated from the second to fifth day of anthesis in three times. Pollen samples were evaluated for their in vitro viability through standard germination test in liquid and solid media and tetrazolium staining. The experimental design was completely randomized, in 4x4x3 split-split plots with four replicates. Data were subjected to analysis of variance followed by a means clustering test and linear regression analysis. The average percentage of viable pollen varied according to the day, collection time, and cultivar. In general, XB 8010 and BRS 2020 had the highest frequency of viable pollen. The highest percentages of viable pollen were observed on the second day of anthesis at 10:00h.

Floral morphology, pollen viability and pollinizer efficacy of persimmon

Persimmon (Diospyros kaki L.), also known as Japani Phal, is a deciduous tree adapted to warm temperate and subtropical climates. Cultivar Hachiya and two staminate genotypes of persimmon were studied for floral morphology. The flowers of staminate and pistillate cultivars exhibited different morphology with respect to flower size and the presence/absence of reproductive parts. Maximum anthesis and anther dehiscence was recorded during early morning 6:00-8:00 am, whereas, minimum during evening up to 2:00 pm and stopped completely thereafter. Stigma receptivity was found to be highest on the day of anthesis. Pollen length and width (29.25 × 21.80 μm) was recorded highest in Diospyros virginiana while, lowest (27.60 × 20.25 μm) was found in Kandaghat Pink. Prolate shape of pollen was recorded in both the genotypes. The pollen grains of both the staminate genotype were ovate when dry and assumed a circular shape on imbibition of moisture. Maximum pollen viability of both the cultivars was observed in Acetocarmine solution, followed by Tetrazolium Chloride and lowest in Erythrosine B. Highest pollen germination (64.10%) in Kandaghat Pink was recorded in 15% sucrose solution followed by 10% (42.50%) and lowest in 5% sucrose solution (20.10%). Both the pollinizers proved to be effective in inducing high fruit set and reducing fruit drop suggesting that both the genotypes can be effectively used as pollinizer for cultivar Hachiya.

Pollen Limitation in a Rare Cactus with Synchronous Mass Flowering

Abstract: Plant fitness is reduced by pollen limitation when the amount and quality of pollen deposited on stigmas is restricted. Pollen limitation has direct implications in mating system and floral evolution, and negatively affects population dynamics. We assessed pollen limitation in the cactus Ariocarpus kotschoubeyanus from the western Chihuahuan Desert. We performed a supplementary pollen treatment then compared outcomes with naturally pollinated flowers using generalized linear models (GLM) and a pollen limitation index (L). Floral aperture was compared between days of anthesis using a single ANOVA, whereas nectar production was contrasted between covered/uncovered flowers and days of anthesis using a factorial ANOVA. Results of both GLM and L show that seed set proportion decreases 0.22 as a result of pollen limitation in natural pollinated flowers contrasted with pollen-supplemented flowers. Most flowers opened two days, and floral aperture between the first and second day varied slightly. Nectar...

Two-Dimensional Gel Electrophoresis-Based Proteomic Analysis Reveals N-terminal Truncation of the Hsc70 Protein in Cotton Fibers In Vivo.

On two-dimensional electrophoresis gels, six protein spots from cotton ovules and fibers were identified as heat shock cognate 70 kD protein (Hsc70). Three spots corresponded to an experimental molecular weight (MW) of 70 kD (spots 1, 2 and 3), and the remaining three spots corresponded to an experimental MW slightly greater than 45 kD (spots 4, 5 and 6). Protein spots 1, 2 and 3 were abundant on gels of 0-day (the day of anthesis) wild-type (WT) ovules, 0-day fuzzless-lintless mutant ovules and 10-day WT ovules but absent from gels of 10-day WT fibers. Three individual transcripts encoding these six protein spots were obtained by using rapid amplification of cDNA ends (RACE). Edman degradation and western blotting confirmed that the three 45 kD Hsc70 protein spots had the same N-terminal, which started from the T271 amino acid in the intact Hsc70 protein. Furthermore, quadrupole time-of-flight mass spectrometry analysis identified a methylation modification on the arginine at position 475 for protein spots 4 and 5. Our data demonstrate that site-specific in vivo N-terminal truncation of the Hsc70 protein was particularly prevalent in cotton fibers, indicating that post-translational regulation might play an important role in cotton fiber development.

Deciphering Transcriptional Programming during Pod and Seed Development Using RNA-Seq in Pigeonpea (Cajanus cajan)

Seed development is an important event in plant life cycle that has interested humankind since ages, especially in crops of economic importance. Pigeonpea is an important grain legume of the semi-arid tropics, used mainly for its protein rich seeds. In order to understand the transcriptional programming during the pod and seed development, RNA-seq data was generated from embryo sac from the day of anthesis (0 DAA), seed and pod wall (5, 10, 20 and 30 DAA) of pigeonpea variety “Asha” (ICPL 87119) using Illumina HiSeq 2500. About 684 million sequencing reads have been generated from nine samples, which resulted in the identification of 27,441 expressed genes after sequence analysis. These genes have been studied for their differentially expression, co-expression, temporal and spatial gene expression. We have also used the RNA-seq data to identify important seed-specific transcription factors, biological processes and associated pathways during seed development process in pigeonpea. The comprehensive gene expression study from flowering to mature pod development in pigeonpea would be crucial in identifying candidate genes involved in seed traits directly or indirectly related to yield and quality. The dataset will serve as an important resource for gene discovery and deciphering the molecular mechanisms underlying various seed related traits.

Heat Unit Accumulation and Days to Anthesis Relationship in Tobacco Genotypes with an Introgressed QTL Affecting Leaf Number

Plant breeders and crop managers would benefit from an increased ability to predict the requirements for onset of anthesis in tobacco (Nicotiana tabacum L.). This study was performed to determine the relationship in the field between heat unit (HU) accumulation and the onset of anthesis in tobacco genotypes varying for the zygosity of an introgressed quantitative trait loci (QTL) designated as Many Leaves (Ml) affecting flowering team and leaf number. Three commercially important cultivars or breeding lines (Speight 168, K326, and NCTG‐61), their nearly isogenic homozygous (MlMl) and heterozygous (Mlml) counterparts, and three BC6F3 null‐segregant (mlml) lines, were evaluated at three locations and over 2 yr. Days to anthesis (DTA) and HU accumulation were determined. In each environment, the MlMl, Mlml, and mlml genotypes were found to be grouped according to the zygosity of the Ml trait, with the mlml genotypes flowering first followed by Mlml and MlMl genotypes, respectively. An exception to this trend was Speight 168 MlMl, which consistently fell within the Mlml grouping for DTA. No consistent relationships were observed between HU and DTA, which was highly variable among environments. Integrated HU (area under the HU curve) during the 28 d after transplanting (DAT) was positively associated (R2 = 0.98; P = 0.0001) with the range of DTA among all genotypes. Integrated HU was a better indicator of the pattern of HU attainment than merely the amount. Early HU exposure seemed important in determining the range in DTA amongst the genotypes examined.

Anthocyanin pigmentation study in flower petals of Asiatic hybrid lily

- Lilium is very important bulbous flower, cosmopolitan and has high demand in International flower market. Asiatic hybrid lily cultivars often have dark red spots on the interior surface of their petals. Pigments accumulated in petal spots are anthocyanins. In Lilium, the genetic basis of flower colour and spot formation are little understood because of the heterozygous genome structure. In this study 10 intravarietal Lilium hybrids along with their parents were tested and evaluated. The aim of this study was to estimate and analyse the flower colour of Asiatic Lilium hybrids. Highest value of anthocyanin was recorded in the hybrid PKLH-12 (43.48 mg/100g) and lowest in hybrid PKLH-6 (3.670 mg/100g). Anthocyanin content in the basal part was slightly higher (12.02 mg/100g) than the upper part (12.00mg/100g). Lilium petal during day of anthesis exhibits the highest amount of anthocyanin (13.96 mg/100g) than the 2 days after anthesis(10.05 mg/100g). Based on the variation in anthocyanin content in the present genotypes it may be concluded that this variability can be used for further development of indigenous hybrids with altered colours, hues, and patterns with long post harvest life. This study is important to understand the genetic basis of the traits and to apply molecular markers linked to map loci for MAS.

Three psychophilous Asteraceae species with distinct reproductive mechanisms in southeastern Brazil

ABSTRACTThe Asteraceae have a high diversity of reproductive mechanisms, as shown by studies conducted mainly with species from temperate regions. Aiming to contribute knowledge on the reproduction of tropical species, we compared the floral biology and breeding systems of the co-occurring species Adenostemma brasilianum, Bidens segetum and Grazielia intermedia, and additionally identified their pollinators. The study was conducted in a seasonal semideciduous forest fragment in southeastern Brazil. Florets opened in early morning and were protandrous. In the first day of anthesis, secondary pollen presentation occurred during the staminate phase, mainly in the morning. In the same day, the pistillate phase began, being long in A. brasilianum and B. segetum (up to 4 days) and short in G. intermedia (1 day). Pollen viability was high in all three species, except for two G. intermedia individuals which showed male sterility, thus characterising a gynodioecious population. Self-compatibility was observed in A. brasilianum and self-incompatibility in B. segetum. In G. intermedia, besides sexual reproduction, apomixis was also observed. This is the first report of apomixis in the genus Grazielia. Although the studied species show distinct reproductive mechanisms, all of them benefitted from cross-pollination, which was mostly done by butterflies.

Implications of High Temperature and Elevated CO2 on Flowering Time in Plants.

Flowering is a crucial determinant for plant reproductive success and seed-set. Increasing temperature and elevated carbon-dioxide (e[CO2]) are key climate change factors that could affect plant fitness and flowering related events. Addressing the effect of these environmental factors on flowering events such as time of day of anthesis (TOA) and flowering time (duration from germination till flowering) is critical to understand the adaptation of plants/crops to changing climate and is the major aim of this review. Increasing ambient temperature is the major climatic factor that advances flowering time in crops and other plants, with a modest effect of e[CO2].Integrated environmental stimuli such as photoperiod, temperature and e[CO2] regulating flowering time is discussed. The critical role of plant tissue temperature influencing TOA is highlighted and crop models need to substitute ambient air temperature with canopy or floral tissue temperature to improve predictions. A complex signaling network of flowering regulation with change in ambient temperature involving different transcription factors (PIF4, PIF5), flowering suppressors (HvODDSOC2, SVP, FLC) and autonomous pathway (FCA, FVE) genes, mainly from Arabidopsis, provides a promising avenue to improve our understanding of the dynamics of flowering time under changing climate. Elevated CO2 mediated changes in tissue sugar status and a direct [CO2]-driven regulatory pathway involving a key flowering gene, MOTHER OF FT AND TFL1 (MFT), are emerging evidence for the role of e[CO2] in flowering time regulation.

Comparative evaluation of maize (Zea mays L.) genotypes based on distinctness, uniformity and stability (DUS) testing using physiological and morphological characters

A major challenge facing those involved in the testing of new plant varieties for Distinctness, Uniformity and Stability (DUS) is the need to compare them against all those of ‘common knowledge’. A set of maize inbred lines was used to compare how morphological and physio- logical characterization described variety relationships. An experiment was carried out to evaluate test of Distinctiveness, Uniformity and Stability using 26 physiological and 12 morphological characters. Minimum days for 50 % tasseling (50.66 and 50.66 days), minimum days for 50 % silking (53.66 and 53.66 days), minimum days for anthesis silking interval (3.0 and 2.6 days), maximum tassel branching (22.66 and 21.66), maximum cob height (89.70 and 89.16 cm) and maximum cob length (16.96 and 17.75 cm) were recorded in genotype AAIMS-1 in both experiments (2011 and 2012 respectively) and maximum cob width (12.51 and 13.11 cm) and maximum number of grain rows per cob (12.66 and 12.66) were recorded in genotype AAIMS-2 in both experiments (2011 and 2012 respectively). But maximum plant height (155.13 and 153.71cm), minimum days for maturity (86.00 and 88.00 days), maximum grain yield per plant (72.80 and 72.00 g) and maximum 100 seed weight (21.51 and 20.96 g) were recorded in genotype AAIMS-2 and AAIMS-1 respectively in both experiments conducted at experimental farm of Department of Genetics and Plant Breeding, Sam Higginbottom Institute of Agriculture, Technology &amp; Sciences during the year 2011 and 2012 respectively.