Peduncle Diameter Research Articles

Comparative development of five sympatric coastal Fundulid species from the northern Gulf of Mexicoa

There are five coastal fundulid species in the northern Gulf of Mexico (nGOM) including Fundulus jenkinsi, which is recognized within all states from Louisiana through Florida and federally as a Species of Concern. This particular fundulid was listed because of a perceived linkage to salt marsh habitat, only scant data available on its ecology, and salt marsh habitat being altered throughout its range. Little is known about the life history of this coastal killifish, but a detailed diagnostic key of the early life stages of select members of Fundulidae can provide the foundation needed to accurately identify this rare species in need of conservation. Larval and postlarval stages of select members of the family Fundulidae along the east coast of the U.S. have been described and compared among species. We illustrated various stages of coastal Fundulus spp. and Adinia xenica in the northern GOM and quantified morphometric and meristic characters. Total length, head length, body depth, caudal peduncle width, snout length, eye diameter, anal and dorsal fin counts, and diagnostic pigment patterns were compared among species. The first branch of our dichotomous key utilized the number of branchiostegal rays to separate young fundulids (< 15 mm TL) into two groups that can then be identified by selected pigment patterns, morphometrics, and meristics.

ORNAMENTAL FOLIAGE POTENTIAL OF ANTHURIUM ACCESSIONS

The Anthurium genus comprises about 1100 species, most of them with ornamental potential. In the last few years the commercialization of new foliage has been growing up. It is necessary to introduce new foliage crops into the market and Anthurium species are an excellent option for cut foliage exploration. The aim of this work was to evaluate ten native Anthurium accessions, through morphological descriptors. The following characteristics were evaluated: leaf shape; petiole colour, length and diameter; main nervure colour; pulvine colour and aspect; inflorescence peduncle length and diameter; spadix colour; spathe shape, length and colour. Evaluation was made for: plant height, growth habit, leaf number, pot fulfillment and emitted shoot number. A large variation was observed for leaf, inflorescence and general plant aspects in all accessions. Some plant characters like height, growth habit, number of emitted shoots are important to define plant spacing, pot size and crop management. The leaf appearance was the most important part of plant to be considered in a first selection: leaf shape, long and straight petioles, diameter with no more than 20 mm are desired morphological characteristics for cut foliage. Accessions with short petioles and a large number of leaves and high pot fulfillment capability maybe better adapted to growth as potted plants. The ten characterized accessions present foliage characteristics for commercial exploration and could be used as material for future breeding programs since wild species plays an important role in the interspecific breeding. As its commercial exploitation is relatively recent, basic information is needed regarding growth aspects of the native Anthurium.

Determination of gene escape and fruit quality characteristics in transgenic melon (Cucumis melo L. var. inodorus)

Gene escape and fruit quality characteristics of transgenic melons (Cucumis melo L. var inodorus cv. 'Kirkagac 637') resistant to zucchini yellow mosaic virus (ZYMV) and control plants were investigated under screenhouse conditions. No significant differences were observed between transgenic and transgenic × control genotypes, with regard to rind thickness, fruit cavity length, fruit cavity width, total soluble solids, pistil scar diameter, and peduncle length. Fruit characters, including fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter were significantly different. These results indicate that transgenic × control genotypes had higher values than transgenic (T4 and T20) genotypes, regarding fruit weight, fruit width, fruit length, fruit flesh thickness, and peduncle diameter. Significant differences were not observed between transgenic (T4 and T20), control, and transgenic × control genotypes in terms of L-ascorbic acid, malic acid, citric acid, sucrose, glucose, or fructose, but differences were observed for fruit total acidity. Esters, lactones, and alcohols were aroma components, but none differed significantly between the transgenic and control genotypes. The results show that there was 100% gene escape in the control plants within 10 m of the transgenic plants, while there was 70% gene escape in plants 12.5, 15, and 17.5 m from the transgenic plants under screenhouse conditions.

EFFECT OF STEM TIP EXCISION, SPRAYING WITH BENZYLADENINE AND CYCOCEL ON FLOWERING OF TWO CULTIVARS OF Gerbera jamesonii

This study was carried out in the College of Agriculture and Forestry, Mosul University, between February and November/2006 on Gerbera jamesonii cv. Esstafette (red inflorescence) and Essandre (yellow inflorescence), to investigated the effect of stem tip excision and spraying plants with benzyl adenine (BA) at 0, 250 and 500 mg.l-1 or Cycocel (CCC) at 500 and 1000 mg.l-1 separately, on flowering character. The factorial experiment was conducted by using randomized complete block design, each treatment was replicated three times with four plants in block. The results can be summarized as follows: Inflorescence taken from Essandre plants recorded higher values of diameter 76.50 mm, while Estafette inflorescences recorded longest peduncles 34.32 cm, and dry weight of peduncles.Stem tip excision plants caused a significant decrease of inflorescences number, diameter, and dry weight, in addition to peduncle diameter, and scape dry weight. Spraying plants with BA at 500 mg.l-1 gave a significant increase in inflorescences number 5.52 inflorescence/plant, and dry weight of inflorescence 8.63 and 1.71 g, respectively in addition to peduncle length, and scape dry weight when compared with control. Treated non-pinched plants with BA at 250 and 500 mg.l-1 gave higher number of inflorescences 6.59 and 6.82 inflorescences/plant for Estafette cultivars, respectively and for Essandre cultivars 5.87 and 6.00 inflorescences/plant respectively. Furthermore, the treatments above pointed to the best results of other inflorescences characters for two cultivars.

Taxonomic Study of the Carex tenera Group (Cyperaceae)

According to previous molecular study, the Carex tenera group sensu lato consists of C. tenera s. l. and C. normalis in one clade and C. festucacea, C. oronensis, and C. tincta in a sister clade. We found that Carex tincta, clarified by thorough review of herbarium materials, has a much narrower geographic range than previously thought, centering on Maine (U. S. A.), adjacent states, and adjacent portions of Canada with rare scattered occurrences to western Lake Superior. Carex tenera has traditionally been thought to consist of two varieties: the transcontinental variety tenera and the upper Midwest (U. S. A.) variety echinodes. In light of ecological and chromosomal differences, AFLP genetic distances, and morphological analysis the latter should be recognized as a distinct species, Carex echinodes comb. et stat. nov. Carex echinodes and narrow-leaved forms of C. normalis can be challenging to differentiate morphologically, but widest leaf width, inflorescence internode length, peduncle diameter, and growth habit separate the two taxa. New chromosome numbers are reported, with those of C. tenera (n = 24 + 2III, 26, 27, 28) having a lower range than either those of C. echinodes (n = 37, 38, 39) or C. normalis (n = 34, 35, 36).

Phenotypic and AFLP characterization of two new pineapple somaclones derived from in vitro culture

Fifty pineapple buds (cv. Red Spanish Pinar, donor) were collected from field-grown plants and cultured in vitro. Forty-three young pineapple shoots were obtained after 42 d of implantation. Shoots were micropropagated for 168 d to produce 24,768 shoots. Three hundred young leaves were randomly selected as explants for callus formation. Calli proliferated for 4 months. Five hundred calli were randomly selected and transferred to the plantlet regeneration medium. Four hundred twenty-seven in vitro-plantlets were obtained and later hardened ex vitro. Then, 387 plantlets were transferred to the field environment and asexually propagated for two generations (30 months). Only two phenotype variants were identified: P3R5 and Dwarf. A more detailed study was carried out to compare these two variants with the donor plant. The variant P3R5 showed differences in the number of slips and suckers, and in the presence of thorns in the leaves and in the fruit crowns. The somaclonal variant Dwarf, was different from the donor plant in regard with the plant height; the peduncle diameter; the number of shoots, slips and suckers; the fruit mass with crown; the number of eyes in the fruit; the fruit height and diameter; the leaf color; the plant architecture; the length of plant generation cycle; and the fruit color and shape. Both somaclonal variants showed different AFLP banding patterns in comparison with the donor cultivar.

Response of Lachenalia growing in soil to nitrogen fertilisation during the pot plant phase

Lachenalia bulbs used in the pot plant industry are produced in the nursery phase from bulblets propagated from leaf cuttings. Fertilisation during this phase of enlargement can ultimately influence the growth and flowering of pot plants through the nutritional status of the bulbs. The objective of this study was to determine the response of cultivars (Rupert and Ronina) in the pot plant phase to different nitrogen levels when grown from bulbs whereof the fertilisation history is known. During the nursery phase bulblets of cultivars Rupert and Ronina received three nitrogen levels (0, 250 and 520 kg N ha−1) combined with two different application times. The resulting bulbs were planted in the pot plant phase and five nitrogen levels (0, 70, 180, 330 and 520 kg N ha−1) applied. Ronina leaf area responded better than Rupert when fertilised in the pot plant phase. The leaf area was also promoted by nitrogen applied in the nursery phase. Nitrogen applied in the nursery and pot plant phases influenced the number of florets formed per inflorescence positively. Only high nitrogen levels applied in the nursery phase (250 and 520 kg N ha−1) increased the peduncle length of the plants. Peduncle diameter was increased with an increase in nitrogen levels in the nursery phase as well as in the pot plant phase. This trial showed that Lachenalia has a low nitrogen requirement in the pot plant phase when grown from bulbs that were properly fertilised in the nursery phase but additional fertiliser in the pot plant phase improved the quality of the inflorescence.

A Comparative Study of Inflorescence Characters and Pollen‐Ovule Ratios among the Genera Philodendron and Anthurium (Araceae)

Floral characters in angiosperms may be involved in different relationships in order to ensure and maximize pollination. To assess these relationships, which may provide insight to understand floral evolution, we analyzed 14 floral characters in 23 species of Philodendron and 20 species of Anthurium, which are tropical long‐living plants bearing spadiciform inflorescences. Contrary to what has been reported in the literature, no correlations were found between the pollen volume and either the style depth or the stigma depth. The trade‐off between pollen size and number normally explained by limited resources was found only in Philodendron. Instead, pollen number was positively correlated with the inflorescence peduncle diameter. The higher range of variation of inflorescence peduncle diameters in Anthurium may explain the lack of correlation between pollen size and number. These results suggest that adaptive constraints driving pollen size and number could differ in the Philodendron and Anthurium genera f...

The Sap Flow in the Peduncle of the Mango (Mangifera indica L.) Inflorescence as Measured by the Stem Heat Balance Method

The transpired mass flow of water from the inflorescence was monitored continuously and compared with the flow in the whole shoot attached to the inflorescence by the stem heat balance method. The transpiration was compared with the chamber method. The stem heat balance method is able to continuously measure the intact sap flow of water. Modified sap flow gauges were adapted to obtain precise measurements of minute fluctuations in the flow. The stem sap flow fluctuated with the solar radiation, reaching a maximum at midday. The flow was also affected by the saturation deficit. At midday, a sap flow rate was 60 g · h−1 at the shoot base (11.5 mm in diam.); the shoot subtended 55 leaves between the shoot base and the terminal inflorescence. At the peduncle of the inflorescence, the maximum sap flow rate occurred during the morning. Subsequently, the flow tended to decrease gradually and steadily, hardly affected by the solar radiation and the saturation deficit. An entire inflorescence with a peduncle diameter of 11.2 mm exhibited a maximum transpiration rate of 15 g · h−1 during late morning. The daily water consumption of the inflorescence was estimated to be 130 g, representing 22% of the water consumption by the entire shoot. The chamber method indicated similar results as the stem heat balance method.

Temperature regime during bulb production affects foliage and flower quality of Lachenalia cv. Ronina pot plants

Flowering-sized bulbs of Lachenalia that developed under three different temperature regimes [S. Afr. J. Plant Soil 18 (1) (2001a) 28] were used to assess the quality of subsequent pot plants. Plants were grown in a growth cabinet at a 15/10 °C day/night temperature regime. When the oldest flower of the inflorescences opened, the pot plants were transferred to a growth cabinet that provided a constant temperature of 22 °C with lower lighting conditions to simulate office conditions. The flowering date, keeping ability as well as the morphology of the inflorescences were evaluated. After the senescence of the inflorescences, the plants were harvested and dissected into different plant parts for evaluation. The temperature pre-treatments had a major effect on the performance of the subsequent pot plants. Flowering occurred 8 weeks earlier compared to plants normally grown in outdoor conditions in the Pretoria region (summer rainfall area). Furthermore, the low temperature regime (LTR) treated bulbs produced inflorescences with the longest keeping ability and simultaneous flowering was noticed. The lower the temperature regime during the bulb production phase, the greater is the peduncle length, rachis length, floret number as well as the peduncle diameter of the primary, secondary and tertiary inflorescences.

Produção de crisântemo (Dendranthema grandiflora Tzvelev.) 'Snowdon' em vaso I: doses e freqüências de aplicação de daminozide

O trabalho teve como objetivo avaliar a resposta de crisântemo através da análise de parâmetros fenométricos, ao redutor de crescimento Daminozide, pulverizado na cultivar de crisântemo de corte "Snowdon", cultivada em vaso. O estudo foi formado por dois ensaios com cinco repetições, usando delineamento experimental inteiramente casualizado em esquema fatorial 4 x 2, sendo formado por quatro doses de Daminozide (0, 2.000, 4.000 e 6.000 mg.L-1) e duas freqüências de aplicações (semanal e bissemanal). Os resultados evidenciaram que as diferentes doses e freqüências de aplicações reduziram a altura da planta, o número de nós, o comprimento de entrenós, o diâmetro da inflorescência e o comprimento do pedúnculo floral. Entretanto, constatou-se aumento dos diâmetros da haste e do pedúnculo floral. Na dose 4.000 mg.L-1 aplicada semanalmente, produziram-se os vasos de melhor qualidade, com altura da planta nos padrões recomendados para comercialização.

Vascular tissues development of citrus fruit peduncle is promoted by synthetic auxins

The application of synthetic auxins to entire trees of'Okitsu' Satsuma and 'Fortune' mandarins significantlyincreases fruit peduncle diameter. This effect is partially due to the increaseof fruit size promoted by the auxins, but is also due to a direct effect of thesynthetic auxins promoting the development of peduncle vascular tissues. Bothxylem and phloem development is affected by the auxins. This direct effect hasbeen shown by applying the auxins locally to the fruit or to the peduncle.

Effect of planting methods and N rates on lodging, morphological characters of culm and yield in spring wheat varieties

The aim of the investigation was to test high yielding spring wheat varieties under different N rates and planting methods for characterizing the lodging resistance parameters and enhancing the yield by reducing lodging. Bed planting increased stem weight (8.1 %), spike weight (7.2 %), diameter of first (3.8 %), second (7.1 %), third (8.2 %) intemode and peduncle (9.0 %) as compared to flat planted crop and this lead to 70-75 % reduction in lodging score. Raising on beds also gave significantly higher biomass (18.48 t/ha), grain yield (8.75 t/ha), thousand grain weight (41.1 g), grainslspike (42) and grains/m 2 (19154) as compared to other planting methods, despite lodging during last irrigation (25-30 days after anthesis). On the other hand, grain yield under permanent bed system (non-tilled during last five years) was 28 % lesser than bed planting due to 25-30 % reduction in spikes/m 2 and grains/m 2 . Effect of N rates on yield and morphological parameters was at par due to recommended or higher N use besides green manuring. Baviacora 92 produced significantly higher biomass (17.1 t/ha), grain yield (8.5 t/ha) and had significantly higher stem and spike weight, diameter and stem wall thickness of different intemodes than other varieties. It also recorded 7 % higher grain yield with bed planting (9.5 t/ha) as compared to flat planting (8.8 t/ha). Since this variety didn't lodge in either planting system therefore it could be said that increase in yield was due to planting on beds. So, it can be said that wheat growing on beds reduces lodging by way of more vigorous stem development and enables to exploit potential yield.

The Initial Domestication of Cucurbita pepo in the Americas 10,000 Years Ago

Squash seeds, peduncles, and fruit rind fragments from Archaic period stratigraphic zones of Guilá Naquitz cave in Oaxaca, Mexico, are assigned to Cucurbita pepo on the basis of diagnostic morphological characters and identified as representing a domesticated plant on the basis of increased seed length and peduncle diameter, as well as changes in fruit shape and color, in comparison to wild Cucurbita gourds. Nine accelerator mass spectrometer radiocarbon dates on these specimens document the cultivation of C. pepo by the inhabitants of Guilá Naquitz cave between 10,000 to 8000 calendar years ago (9000 to 7000 carbon-14 years before the present), which predates maize, beans, and other directly dated domesticates in the Americas by more than 4000 years.

Quantitative characteristics of the conducting system in stem of winter wheat genotypes with spike fertility genes

Three groups of winter wheat (Triticum aestivum L.) genotypes having spike fertility genes (SFG) were used in field trials: (1) Tetrastichon sessile spikelets (TSS), (2) Normal spikelets (NS), (3) Indeterminate rachilla spikelets (IRS). The capacity of conducting system of the peduncle and the ear sink capacity of the main stem have been measured. There was a highly significant positive correlation (r = 0.899 and higher) between peduncle diameter and parameters quantifying peduncle vascular system. Compared with the control cultivar Hana, the TSS and NSS genotypes had higher both the number of vascular bundles, phloem and bundle cross section area and kernel number per ear. However, the highest kernel number per ear was found in the IRS genotypes although their bundle and phloem area was only equal or even lower then that of the variety Hana. Further studies are needed in developmental anatomy of spikes and stems to elucidate also differences in the relationships between the conducting capacity and kernel number per spikes in the TSS, NS and IRS genotypes.

NECTAR PRODUCTION AND FLORAL CHARACTERISTICS IN BIRDSFOOT TREFOIL (Lotus corniculatus L.)

Nectar production was studied in several varieties of birdsfoot trefoil in relation to flower color, aroma, and some anatomical features in order to identify characteristics which might be of use in a program of selection for attractiveness to honeybee pollinators. Color did not appear to be an important variable; no major varietal differences in light reflectance were noted at any wavelength. There was a twofold varietal range in nectar yield per umbel and a larger difference in potential yield per plant. Selection within varieties increased the difference between high- and low-nectar plants by several times. Large varietal differences in aroma strength were also noted. While nectar and aroma production were not closely correlated in all varieties, those with weak aroma were generally low nectar yielders. Nectar yield per umbel was directly related to the cross-sectional area of functional phloem in the peduncle, and the amount of functional phloem and peduncle diameter were closely correlated. The ratio of nectar yield to phloem supply was much larger in high-nectar than in low-nectar plants, indicating an important effect of an unidentified factor. Preliminary screening in selection for high nectar lines could be facilitated by discarding plants whose flowers have small peduncles and weak aroma.

SEASONAL VARIATIONS IN THE CHARACTERISTICS OF RASPBERRY FRUIT DROP

Several berry characteristics relating to raspberry (Rubus idaeus L. ’Willamette’) fruit drop were measured during the 1971, 1972, and 1973 harvest periods. These characteristics included fruit removal force, peduncle strength, berry weight, berry ripeness, and receptacle and peduncle dimensions. All of the characteristics exhibited large fluctuations during the harvest periods. Fruit removal force and peduncle strength were particularly variable; during the 1972 harvest period each of these characteristics decreased to less than one-fifth of its original value. The only characteristics that showed net increases during the harvest period were peduncle diameter and average berry ripeness. Among the characteristics surveyed, peduncle strength was correlated with berry weight and peduncle length, and was inversely correlated with peduncle diameter. Decreases in fruit removal force were correlated with increased berry ripeness and decreased receptacle dimensions. These results may assist in the improvement of the design or use of mechanical raspberry harvesters.

SOME BIOMETRICAL STUDIES ON NINE AGRONOMIC TRAITS IN GRAIN SORGHUM, SORGHUM BICOLOR (L.) MOENCH: I. Variance Components and Heritability Estimates

The investigation was designed to estimate genetic and environmental variability and heritability for a number of agronomic characters in grain sorghum. The study was made in the F3 and F4 generations of three crosses grown at two locations in each of two years. Heritability estimates were computed by three methods: by variance components and by the regression of the F4 generation on the F3, using both conventional and standard-unit methods.In general, the genotypic components of variance were larger than those of the genotype × environment interactions. With few exceptions, second-order interactions were larger than first-order interactions. Although the first-order interactions are of lower magnitude, they should not be interpreted as though the genotype × year and genotype × location interactions did not exist; they may be a reflection of the nature of the lines tested and environments sampled. Most heritability estimates obtained from the three methods were in close agreement. Heritability estimates for half-bloom date, peduncle diameter, and plant height for all crosses were high regardless of the method of calculation. Grain yield, head weight, kernel weight, and kernel number showed moderately high heritability values, while those for head number and threshing percentage appeared to be low.

HERITABILITY ESTIMATES AND INTERRELATIONSHIPS AMONG AGRONOMIC TRAITS IN GRAIN SORGHUM, SORGHUM BICOLOR (L.) MOENCH

Heritability was estimated for 12 agronomic traits in two segregating grain sorghum populations in F3 and F4 generations by parent-offspring regression, parent-offspring correlation, and variance component methods. Half bloom, leaf number, and plant height were most heritable in both populations; head number was least heritable. Grain yield, head weight, kernel number, peduncle diameter, germination percentage, and threshing percentage had medium heritability values. Kernel weight and protein percentage were highly heritable in one population but less heritable in the other.Estimates of genetic correlations showed grain yield positively and strongly correlated with head weight, kernel number, half bloom, leaf number, and plant height, but negatively correlated with germination and protein percentages.Selection indexes constructed using various combinations demonstrated that selecting for yield could be more efficient if combinations other than or in addition to yield were utilized. Selection indexes were less effective in selecting for protein when protein was not included in the index.

Studies on heterosis in pearl millet (Pennisetum typhoides stapf & hubb)

A complete diallel cross study of ten pearl millet inbred parents was used to estimate g.c.a. and s.c.a. for grain yield and eight other related characters (length and diameter of peduncle, surface area of primary ear, density of grain, yield of primary ear, plant height, tillering capacity and yield of straw). General combining ability effects were of a lesser order than those of s.c.a. for most of the characters studied. Highly significant s.c.a. effects for many characters point to the immense practical value of utilising the same in the exploitation of heterosis. Lines with superior g.c.a. and hybrids manifesting outstanding s.c.a. in respect of each character could be marked out.