Floral Parameters Research Articles

Flower regulation in spray chrysanthemum cultivars by staggered planting in Himachal Pradesh

The present investigation was carried out at the experimental farm of the Department of Floriculture and Landscape Architecture of Dr. YS Parmar University of Horticulture and Forestry, Nauni, Solan. The investigations were carried out on 4 spray commercial cultivars i.e. ‘Surf’, ‘Nanako’, ‘Ajay’ and ‘White Bouquet’ of chrysanthemum. These cultivars were planted on 9 planting dates at an interval of 15 days starting from April 9 to August 7. Significant difference was obtained among spray the cultivars for all vegetative and floral parameters. Though, successful flowering in spray type cultivars of chrysanthemum included in the studies was obtained in all the planting dates, however, later plantings resulted in cut stems of shorter length. Among spray types, ‘Surf’ should be planted before July 8, ‘Nanako’ and ‘White Bouquet’ before June 8 and ‘Ajay’ before July for producing marketable cut stems. With the help of planting dates flowering of these cultivars under Solan-Nauni conditions can be regulated from September 10 to November 1 i.e. for 52 days.

Efficacy of auxins and gibberellic acid on floral attributes and essential oil yield on German Chamomile(Matricaria chamomillaL.)

Chamomile (Matricaria chamomilla L.) is one of the important medicinal plants grown for its valuable flowers from which oil is extracted which contains high pharmaceutical value. Plant bio-regulators can be effectively used to enhance both vegetative as well as flowering attributes. Plants were foliarly treated with IAA, GA3 and NAA at three concentrations (25, 50 and 100 ppm) which improved floral parameters like days taken to first bud initiation, flower diameter (cm), number of flowers per plant and fresh and dry weight of flowers per plant (g). Among the different treatments, GA3 at 100 ppm was found to be best treatment for most of the parameters viz. days taken to first bud initiation (15.53), flower diameter (2.57 cm), number of flowers per plant (268.93), fresh weight of flowers per plant (35.56 g) and dry weight of flowers per plant (6.96 g), whereas NAA at 100 ppm proved to be the best for stem diameter (6.76 mm). GA3 @ 100 ppm was found to be the most effective for most of the vegetative and floral characteristics of chamomile cv. CIM Sammohak.

Response of integrated nutrient management on floral, bulb and economic parameters in tuberose cv. Phule Rajani under sub-humid southern plains of Rajasthan

An investigation was carried out at AICRP on Floriculture, Horticulture Farm, RCA Campus, MPUAT, Udaipur to find out response of integrated nutrient management on floral, bulb and economic parameters in tuberose cv. Phule Rajani. Application of neem cake 12 q ha−1 + vermi-compost 20 q ha−1 + Azotobacter @ 2 g plant−1 + PSB @ 2 g plant−1 + 60% recommended dose of NPK through inorganic fertilizers showed significant influence on plant height (82.90 cm), spike length (58.43 cm), floret/spike (30.96), floret diameter (4.10 cm), flower duration (31.63 days), spike durability in field (7.83 days), spike/plant (2.98), ten floret weight (16.25), spike weight (53.26 g), bulbs/plant (3.98), spike ha−1 (3,31,111), bulb ha−1 (4,42,222), gross return (Rs. 8,61,777 ha−1), net return rupees (Rs. 6,20,000 ha−1) and benefit/cost ratio (2.56) with highest trends in this treatment, which was found better over the recommended dose of NPK (120:60:60 kg/ha) through inorganic fertilizers and sole organic - neem cake (12 q/ha) + vermi-compost (30 q/ha) + Azotobacter @ 2 g plant−1 + PSB @ 2 g plant−1.

Variation in Sex Allocation and Floral Morphology in an Expanding Distylous Plant Hybrid Complex

Premise of research. Sex allocation, the relative energy devoted to producing pollen, ovules, and floral displays, can significantly affect reproductive output and population dynamics. In this study, we investigated floral morphology and gamete production in bisexual, distylous plants from a self-incompatible hybrid complex (Piriqueta cistoides ssp. caroliniana Walter [Arbo]; Turneraceae). Sampling focused on two parent types (C, V) and their stable hybrid derivative (H). Since H morphotypes are heterotic for growth and fruit production, we hypothesized that they would produce larger flowers with more gametes. We also anticipated that plants with long styles (long morphs) would produce less pollen than short morphs, since long-morph pollen is larger.Methodology. Over two consecutive summers, flowers were collected from 1465 individual plants in 28 field populations. Floral parameters were measured digitally, and each flower’s pollen number, ovule number, and stigma-anther separation was quantified under a dissecting microscope. Gamete production (n = 332) and stigma-anther separation (n = 119) were also quantified for plants from a greenhouse accession.Pivotal results. Floral display differed among morphotypes, with H plants producing the largest flowers and C plants displaying the least petal separation. Hybrid morphotypes produced significantly more pollen than parental morphotypes, and pollen quantity was significantly greater for long morphs. Ovule production, however, was greatest for V flowers. Stigma-anther separation differed between years and style morphs (greater for short morphs) but not among morphotypes or within a single season.Conclusions. Differences in pollen production between morphs were not consistent with trade-offs in pollen size and number or selection for increased male function in short morphs. Greater stigma-anther separation in short morphs supported the hypothesis of selection to reduce pollen interference. Enhanced floral display and pollen production followed other heterotic traits observed in H morphotypes. The superior ability of H morphotypes to attract pollinators and sire seeds might partially explain this hybrid zone’s continuing expansion.

Effect of pre planting treatment of corms with chemicals and plant growth regulators on vegetative growth, flowering and post harvest life in gladiolus

The effect of thiourea (TU), salicylic acid (SA), potassium nitrate (KNO3) and giberellic acid (GA3) with two corm soaking periods on growth, flowering and post harvest life of two gladiolus cultivars Darshan and Dhiraj was investigated during two consecutive years, 2008-09 and 2009-10. Cv. Darshan was early in flowering and performed better than the cv. Dhiraj with respect to vegetative and floral parameters. Pre-planting soaking of corms for 24 h improved vegetative and flowering attributes. SA 150 ppm followed by TU 2% was more effective in increasing vegetative growth and reducing number of days to flowering. SA 150 ppm followed by GA3 150 ppm were effective in improving flowering performance of gladiolus cultivars in terms of increasing number of spikes per plant, spike length and weight and number of florets per spike. Post harvest studies revealed that soaking of corms for 24 h recorded significantly less number of days to first floret opening. Pre-planting treatment of corms with SA 150 ppm recorded minimum days to first floret opening, maximum number of florets opened at a time per spike and vase life.

Evaluation of Gladiolus Cultivars in Eastern Ghats of Tamil Nadu

Gladiolus grandiflorus L. genotypes were evaluated for growth and floral parameters in Eastern Ghats of Tamil Nadu, under Yercaud conditions. Significant differences were recorded for all traits studied. Among 42 genotypes evaluated, 'Pusa Shagun' and 'Pusa Swarnima' recorded quality spikes with higher vase life indicating their suitability for use in floral arrangement, while, genotypes like 'Thumbolina', 'Priscilla' and 'Candyman' were found superior in characters like corm number, corm weight and corm diameter. Taking into account various growth and floral characters of the genotypes studied, Pusa Swarnima, Pusa Shagun, Thumbolina, Priscilla and Candyman can be recommended for cut-flower production in the Eastern Ghats of Tamil Nadu.

Self-incompatibility, floral parameters, and pollen characterization in the narrow endemic and threatened species <i>Artemisia granatensis</i> (Asteraceae)

Penas, J., Lorite, J., Alba-Sanchez, F. & Taisma, M.A. 2011. Selfincompatibility, floral parameters, and pollen characterization in the narrow endemic and threatened species Artemisia granatensis (Asteraceae). Anales Jard. Bot. Madrid 68(1): 97-105. Artemisia granatensis Boiss. is a paradigmatic species for plant conservation in Spain and Europe. It is a critically endangered (CR) endemic species growing above 2500 m in the Sierra Nevada (southern Spain). Natural populations have been considerably devastated in the past due to intensive human exploitation for folk medicine. The sparse available data concerning the reproductive biology of this species under natural conditions indicate a low reproductive success. To provide additional information on the reproductive biology of A. granatensis, and consequently information useful for the management and conservation of this species, we studied the breeding system through pollen-tube growth. In addition, some floral and pollen traits were recorded. No differences were found between populations in terms of the morphological traits of flowers and inflorescences. A. granatensis is an anemophilous species, and the data indicate that pollen transfer may be limited between isolated populations, and so contributing to an extremely low fruit-set. Results show A. granatensis is selfincompatible, probably with a sporophytic self-incompatibility system, and with no evidence of partial self-incompatibility. Reproductive traits, related to pollen morphology and settling speed may explain the low rate of recruitment in the small populations separated by geographical barriers.

Pollen‐Ovule Ratio and Gamete Investment in Pedicularis (Orobanchaceae)

AbstractThe Pedicularis species provides ideal materials to study floral evolution because of their substantial flower variation based on a narrow genetic basis, even though they are almost exclusively pollinated by bumblebee. These traits allow us to detect the evolutionary trends of floral parameters without considering genetic background and the difference of pollination vectors. The pollen‐ovule ratio is widely used to estimate the pattern of resource investment in two sexual functions in flowering plants. Forty species representing all of the corolla types in Pedicularis were used to study pollen‐ovule ratio, gamete investment, and their correlations. Results show that pollen‐ovule ratio does not differ among both different corolla types and taxonomic groups. It is therefore suggested that pollen‐ovule ratio should be a parallel evolution. The correlations between pollen‐ovule ratio and pollen size (−), and ovule size (+) can be successfully explained in terms of sex allocation theory. The biological significance of such relationships was also discussed. Additionally, we analyzed the pattern of resource investment into female gamete, which has been somewhat neglected, and found that plants have different patterns of gamete investment between the two sexual functions.

Self‐incompatibility and floral parameters inHypochaerissect.Hypochaeris(Asteraceae)

We studied the relationships between self-incompatibility mechanisms and floral parameters in the genus Hypochaeris L. sect. Hypochaeris (consisting of H. glabra, H. radicata, H. arachnoidea, and H. salzmanniana). We assessed at intra- and interspecific levels (1) the self-incompatibility (SI) mechanism and its distribution among populations, (2) the relationship between SI and floral parameters, and (3) the relationship of SI to reproductive success. Hypochaeris salzmanniana is semi-incompatible, H. glabra is self-compatible, and H. arachnoidea and H. radicata are self-incompatible. Floral parameters differed among populations of H. salzmanniana: plants in self-compatible populations had fewer flowers per head, a smaller head diameter on the flower, and a shorter period of anthesis than self-incompatible populations. We also detected this pattern within a semi-compatible population of H. salzmanniana, and these differences were also found between species with different breeding mechanisms. Fruit to flower ratio in natural populations was generally high (>60%) in all species, regardless of breeding system. It is hypothesized that self-compatibility may have arisen through loss of allelic diversity at the S locus due to bottleneck events and genetic drift.

Flower Quality in Orchards of Olive, "Olea europaea" L., cv. Morisca

A complete evaluation of flower quality for the olive tree includes parameters at different levels of morphological organization, from the inflorescence to the pollen and ovule. In this study we examined inflorescence, flower gender, ovary structure, ovule development and pollen integrity in commercial orchards of olive cv. Morisca, suspected of having floral quality limitations to production. Low values were found in flower number, perfect flowers and pollen quality, but fertile inflorescences (with at least one perfect flower), ovary growth and ovule development were normal. The observed shortcomings appear to be a characteristic of this cultivar, but not necessarily a serious limitation to fruit production. In this report, the methods for evaluating different floral quality parameters in the olive tree are described and it is suggested that compensation among them is part of the reproductive strategy of this species.

INFLUENCE OF PLANT SIZE AND CLIMATIC VARIABILITY ON THE FLORAL BIOLOGY OF FOUQUIERIA SPLENDENS (OCOTILLO)

The floral biology of Fouquieria splendens (Fouquieriaceae), a drought-deciduous shrub with wandlike branches, was studied in the northern Sonoran Desert. Two different measures of plant size, number of branches long enough to flower (>1 m in length) and actual number of reproductive branches, were used to examine the effect of plant size on reproductive output and floral display. Number of flowers and fruits increased with either measure of plant size. Annual flower production ranged from 190 to 6465 per plant and averaged 2553. Annual fruit production ranged from 9 to 1760 per plant and averaged 390. Because some branches long enough to flower did not do so, number of reproductive branches was a stronger predictor of flower production than number of branches > 1 m long. Inflorescence size (mean number of flowers per panicle) was not significantly related to plant size (number of flowering branches) in 2002 or 2003; in fact, the range in inflorescence size on certain individual plants was about as wide as the range for the entire sample. Interannual variation in floral parameters was examined by monitoring the same set of branches in two years, one unusually dry, one with nearly normal rain. In 2002, the dry year, panicles were numerous and sparsely flowered; in 2003, the wetter year, panicles were relatively few and much more densely flowered. Although flowers appeared normally abundant in the wetter year, mean number of flowers per branch was in fact 39% lower than in the dry year. Percent fruit set per panicle in 2003 (36%) was more than twice that in 2002 (16%). Even so, average number of fruits per branch did not differ between 2002 and 2003. Evidently flower production on a per-branch basis was high enough in 2002 to compensate for poor fruit set in that year, resulting in about as many fruits as in 2003.

Flower Constancy, Insect Psychology, and Plant Evolution

Individuals of some species of pollinating insects tend to restrict their visits to only a few of the available plant species, in the process bypassing valuable food sources. The question of why this flower constancy exists is a rich and important one with implications for the organization of natural communities of plants, floral evolution, and our understanding of the learning processes involved in finding food. Some scientists have assumed that flower constancy is adaptive per se. Others argued that constancy occurs because memory capacity for floral features in insects is limited, but attempts to identify the limitations often remained rather simplistic. We elucidate now different sensory and motor memories from natural foraging tasks are stored and retrieved, using concepts from modern learning science and visual search, and conclude that flower constancy is likely to have multiple causes. Possible constraints favoring constancy are interference sensitivity of short-term memory, and temporal limitations on retrieving information from long-term memory as rapidly as from short-term memory, but further empirical evidence is needed to substantiate these possibilities. In addition, retrieving memories may be slower and more prone to errors when there are several options than when an insect copes with only a single task. In addition to memory limitations, we also point out alternative explanations for flower constancy. We then consider the way in which floral parameters, such as interplant distances, nectar rewards, flower morphology, and floral color (as seen through bees' eyes) affect constancy. Finally, we discuss the implications of pollinator constancy for plant evolution. To date there is no evidence that flowers have diverged to favor constancy, although the appropriate tests may not have yet been conducted. However, there is good evidence against the notion that pollinator constancy is involved in speciation or maintenance of plant species integrity.

MORPHOMETRICAL CHARACTERIZATION OF CYTISUS AND ALLIES (GENISTEAE: LEGUMINOSAE) AS AN AID IN TAXONOMIC DISCRIMINATION

Twenty-four accessions belonging to the genusCytisusand allied taxa were characterized by adult plant morphometry. Twenty-six characters were measured in flowers, 9 in leaves, and 5 in fruits. Two data sets were prepared, the first including only floral parameters and the second with all the parameters. Two different multivariate analyses were carried out for every data set: cluster analysis and principal components analysis. All these studies produced a similar grouping of the operational taxonomic units. Four clear groups were defined: (i)Cytisophyllum sessilifolium;(ii)Cytisus baeticus, C. reverchonii, C. scoparius., (iii)Chamaecytisusspecies; (iv)Genistaspecies. On the other hand,Cytisus villosusshowed an intermediate position betweenCytisusandChamaecytisus, andCytisus heterochrousand C.purgansan intermediate position betweenCytisusandGenista.This grouping agrees with that obtained by other recent seed morphometry and biochemical studies, and supports the generic arrangement presented by Bisby (1981).

Les cycles de floraison des syntaxons du Sud-Est méditerranéen français : approches statistique et modélisée. Il. Caractérisation des formations végétales et des syntaxons s'y rapportant

In the first part of this paper (Ecologia Mediterranea 3 1983 3 IX(3/4)3 79-128) 3 the interannual variations of the flowering time cycles of 124 phyto-coenosis growing within the limits of the French continental south-eastern mediterranean level have been studied. The authors have evidenced often sharp correlations between different biological variables (biological and biogeographical types statistical floral variables experimental or model floral parameters). They demonstrated that some floral variables (such as the circumscribed inner area of the polar curve and the seasonal type) bring more information than others. Besides all the statistical floral variables are sharply correlated with the biological and biogeographical types. The authors attempted to explain the determinism and the diversity of the flowering in relation to the ecological requirements of the syntaxa. In the second part the différenciation of syntaxa or groups of syntaxa on floral basis has been attempted. The authors have thus evidenced several sub-units among the rupicolous and scree groupings grasslands garrigues maquis cistus-groupings sclerophyllous and deciduous pre-forest and forest groupings . Affinities do exist between synsystematics and floral typology both usually related to the ecological characteristics (especially the thermic ones) of the biotopes.

FLORAL PARAMETERS, BREEDING SYSTEM AND POLLINATOR TYPE IN TRICHOSTEMA (LABIATAE)

Diversity in flower size and degree of exsertion of anthers and stigma from the corolla in the California species of Trichostema appear to be correlated with breeding system and pollinator type (bee vs. bird). Autogamous (self‐pollinating) species unlike xenogamous (cross‐pollinating) species lack spatially separate anthers and stigma and nototribic pollination. The outcrossing species have significantly larger flowers, significantly larger nectar volumes and significantly higher pollen‐ovule ratios than do selfing species. Because autogamous species are less reliant on flower visitors to facilitate pollination, there may be relaxed selection for large nectar producing flowers. Pollen‐ovule ratios are correlated with breeding system and reflect the efficiency of pollen transport. Data on floral parameters suggest xenogamous species expend more energy per floral unit and are less efficient seed producers than closely related autogamous species.

Floral Parameters, Breeding System and Pollinator Type in Trichostema (Labiatae)

Diversity in flower size and degree of exsertion of anthers and stigma from the corolla in the California species of Trichostema appear to be correlated with breeding system and pollinator type (bee vs. bird). Autogamous (self-pollinating) species unlike xenogamous (cross-pollinating) species lack spatially separate anthers and stigma and nototribic pollination. The outcrossing species have significantly larger flowers, significantly larger nectar volumes and significantly higher pollen-ovule ratios than do selfing species. Because autogamous species are less reliant on flower visitors to facilitate pollination, there may be relaxed selection for large nectar producing flowers. Pollen-ovule ratios are correlated with breeding system and reflect the efficiency of pollen transport. Data on floral parameters suggest xenogamous species expend more energy per floral unit and are less efficient seed producers than closely related autogamous species.

Ecology, Flowering Phenology, and Hummingbird Pollination of Some Costa Rican Heliconia Species

Nine hummingbird—pollinated species of Heliconia occur together at Finca La Selva, in the wet Caribbean lowlands of Costa Rica. In forest habitats, Heliconia clumps (clones) are typically small; in more open areas, many clumps attain large size. This probably reflects differences in light intensity and degree of vegetative competition in these habitats. Nine species of hummingbirds regularly visit Heliconia flowers at La Selva. The four hermits are nonterritorial, traplining foragers with long, curved bills. Non—hermits frequently hold territories at Heliconia clumps, and have short, straight bills. Pollination by hermits tends to produce more cross—pollination; territorial hummingbirds increase self—pollination. Different Heliconia species appear to be specialized for pollination by either hermits on non—hermits, largely through components of the caloric phenotype: amount and timing of nectar production, rate of inflorescene and flower production, and morphological paramerters that affect the energetic efficiency of nectar—harvesting hummingbirds. Habitat may influence pollination systems through its effects on clump size and thus on the number of flowers a clump can have at any one time. Ultimately, specialization for hermits or non—hermits may depend on the degree of self—compatibility of the different Heliconia species. Hermit—pollinated Heliconia mostly show sequential and nonoverlapping flowering peaks, probably resulting from competition for pollinators and/or selection against hybridization. Two hermit—pollinated species bloom simultanesoulsy, thereby inducing the birds to utilize an other—wise little—used microhabitat. Heliconia species pollinated by non—hermits bloom in the early to middle rainy season, and are mostly separated by habitat. Isolating mechanisms among sympatric Heliconia species involve both spatial and temporal patterns of partioning available pollinators. Floral parameters include mechanical (different site of pollen deposition on the bird) and ethological (caloric and visual factors affecting flower choice) mechanisms. Selection for pollinator specificity may result in convergence of blooming peaks, provided that other isolating mechanisms are present. Human activity has broken down some habitat barriers by producing large areas of second growth.