Development Of Pistillate Flowers Research Articles

The effect of sex phytoregulators on cucumber productivity

Relevance. Gender phytoregulators occupy an important place in the seed production of parental forms of cucumber, they allow you to shift the sex of the plant in the right direction, increase the intensity of selection, obtain purely female lines, and increase the efficiency of hybrid seed production.Results. The paper presents the regulations for the use of Esfon on the breeding line ZhL 24, which is the mother form of the hybrid Rich garden F1. To obtain the maximum number of female flowers, without significant inhibition of vegetative growth, it is necessary to treat vegetative plants three times with an interval of 5 days, starting from the phase of the second true leaf, with a solution of Esfon (BP. 65%) at a concentration of 0.03% (300 mg/l) with the purpose of preventing closely related crosses and increasing the hybridity of seeds. This technique stimulates the earlier development of pistillate flowers, minimizes the formation of male flowering, increases the number of fruits per plant, their size and weight, which allows increasing the yield per unit area by 40%.

Pleiotropic effects of CmACS7 on fruit growth and quality parameters in melon (Cucumis melo)

CmACS7 is a sex determination gene that is known to be involved in the biosynthesis of ethylene at very early stages of pistillate flower development in melon, promoting so the arrest of stamen during the development of female flowers, and resulting in monoecious plants. Loss-of-function mutations for CmACS7 reduce the production of ethylene in pistillate flowers, which results in hermaphrodite flowers and andromonoecious plants. In this paper we compare fruit growth and quality in monoecious and andromonoecious isogenic lines of five different genotypes of 'Galia' (Cucumis melo var. reticulatus) and 'Cantaloupe' (Cucumis melo var. cantalupensis) melons. The gene not only regulates sex determination but also other fruit growth parameters. The mutation that caused andromonoecy and reduced ethylene in female flowers promoted a reduction in fruit set, fruit weight and number of total and viable seeds, as well as an alteration of fruit shape in the five genotypes analyzed. In some genotypes monoecy stability was reduced, concomitantly with a loss of significant differences between isogenic lines. The gene mutation, however, had no effect on fruit quality parameters such as total soluble solids, fruit pH and titratable acidity. To assess whether these pleiotropic effects of the gene are associated with ethylene biosynthesis, we analyzed production of ethylene in the ovary/fruit of unpollinated flowers during the days immediately after anthesis, confirming a higher induction of ethylene in the monoecious isoline. Results are discussed in relation to ethylene production and autoregulation of ethylene biosynthesis in flowers and fruits.

Floral development and anatomy of pistillate flowers of Lophophytum (Balanophoraceae), with special reference to the embryo sac inversion

The extreme reduction of flowers in the Balanophoraceae has generated few and incomplete studies with scattered and often contradictory results with respect to embryology. Using light and scanning microscopy, gynoecium, ovule and embryo-sac development are described in two (of 4) species of Lophophytum. The pistillate flower lacks perianth, and it is reduced to one pistil formed by a superior, biloculate ovary and two styles with capitated stigmas. Two ategmic hemianatropous ovules are inserted on the upper portion of a central placental column. The two locules are almost completely obstructed by the ovules. The term micropyle is not applicable in its usual sense, due to the absence of integuments. The term “micropylar pole” instead of micropyle was used to designate the apex of the nucellus, where the megaspore mother cell develops. Vascular supply is missing in the placenta and the ovule, therefore, the chalaza and the funiculus cannot be defined. The point of attachment of the nucellus to the placenta was designated “chalazal pole”. The embryo-sac is Adoxa type. During the migration of the two pairs of nuclei to the opposite poles, the four-nucleate embryo-sac tends to take a “J” shape. Each pair of nuclei undergoes a mitotic division to form an eight-nucleate embryo-sac. In the upper, chalazal pole of the embryo-sac, a typical egg-apparatus with a central egg-cell and two adjacent synergids cells is developed, while in the micropylar pole three antipodes are formed, all that determines an embryo-sac of reversed position. The analysis of the anatomy and development of pistillate flowers and the study of the functional architecture of ovules, carpels and embryo-sac, provide embryological data of great importance to complement phylogenetic studies in the family Balanophoraceae, and even in order Santalales.

Pistillate flower development and pollen tube growth mode during the delayed fertilization stage in Corylus heterophylla Fisch.

Unlike most angiosperms, in which fertilization occurs within several days after pollination, fertilization in hazel (Corylus Spp.) is delayed by two to three and a half months. However, the female inflorescences or young fruits are too hard or lignified to be dissected according to regular paraffin sectioning technique. So, what the nature of development during the extended progamic phases of hazel remains unknown. The female inflorescence development and pollen tube growth mode during the delayed fertilization stage in hazel were investigated by improved paraffin sectioning and aniline blue staining of pollen tubes. The results showed ovaries and ovules of hazel were invisible at the time of blooming. Early ovary and ovule primordium began to form from 15 to 20days after blooming, respectively. Integument and mature embryo sacs differentiated from the nucellus on 40th and 55th day after blooming, respectively. Pollen tubes were retarded in the bottom of the style or the pollen tube cavity (PTC, a specifical lignified cavity structure at the bottom of style for pollen tube to rest during progamic phase) for about 26days. Then, the pollen tubes were observed to leave the PTC and began to enter the ovary. After that, a single pollen tube passed through the vicinity of the micropyle. Finally, pollen tubes turned a corner and penetrated the embryo sac through the tissue of the chalaza instead of micropyle on 52 and 55days after blooming, respectively. The results of more in-depth information will be beneficial to better understanding of the delayed fertilization process in hazel.

Use of transcriptome sequencing to understand the pistillate flowering in hickory (Carya cathayensis Sarg.).

BackgroundDifferent from herbaceous plants, the woody plants undergo a long-period vegetative stage to achieve floral transition. They then turn into seasonal plants, flowering annually. In this study, a preliminary model of gene regulations for seasonal pistillate flowering in hickory (Carya cathayensis) was proposed. The genome-wide dynamic transcriptome was characterized via the joint-approach of RNA sequencing and microarray analysis.ResultsDifferential transcript abundance analysis uncovered the dynamic transcript abundance patterns of flowering correlated genes and their major functions based on Gene Ontology (GO) analysis. To explore pistillate flowering mechanism in hickory, a comprehensive flowering gene regulatory network based on Arabidopsis thaliana was constructed by additional literature mining. A total of 114 putative flowering or floral genes including 31 with differential transcript abundance were identified in hickory. The locations, functions and dynamic transcript abundances were analyzed in the gene regulatory networks. A genome-wide co-expression network for the putative flowering or floral genes shows three flowering regulatory modules corresponding to response to light abiotic stimulus, cold stress, and reproductive development process, respectively. Totally 27 potential flowering or floral genes were recruited which are meaningful to understand the hickory specific seasonal flowering mechanism better.ConclusionsFlowering event of pistillate flower bud in hickory is triggered by several pathways synchronously including the photoperiod, autonomous, vernalization, gibberellin, and sucrose pathway. Totally 27 potential flowering or floral genes were recruited from the genome-wide co-expression network function module analysis. Moreover, the analysis provides a potential FLC-like gene based vernalization pathway and an 'AC’ model for pistillate flower development in hickory. This work provides an available framework for pistillate flower development in hickory, which is significant for insight into regulation of flowering and floral development of woody plants.

Maximum Potential Vegetative and Floral Production and Fruit Characteristics of Watermelon Pollenizers

Triploid (seedless) watermelon [Citrullus lanatus (Thunb.) Matsum. and Nak.] pollen is nonviable; thus, diploid (pollenizer) watermelon cultigens are required to supply viable pollen for triploid watermelon fruit set. The objective of this research was to characterize maximum potential vegetative growth, staminate and pistillate flower production over time, and measure exterior and interior fruit characteristics of pollenizer cultigens. Sixteen commercially available and numbered line (hereafter collectively referred to as cultigens) pollenizer and two triploid cultigens were evaluated in 2005 and 2006 at Clayton, NC. Vegetative growth was measured using vine and internode length, and staminate and pistillate flower development was counted weekly. Fruit quality and quantity were determined by measuring individual fruit weights, soluble solids, and rind thickness. Based on vegetative growth, pollenizer cultigens were placed into two distinct groups. Pollenizers, which produced a compact or dwarf plant were ‘Companion’, ‘Sidekick’, ‘TP91’, ‘TPS92’, and ‘WC5108-1216’. Pollenizers having a standard vine length were ‘Jenny’, ‘High Set 11’, ‘Mickylee’, ‘Minipol’, ‘Pinnacle’, ‘Summer Flavor 800’ (‘SF800’), ‘Super Pollenizer 1’ (‘SP1’), and ‘WH6818’. Cultigens with compact growth habit had shorter internodes and vine lengths compared with the cultigens with standard growth habit. Cultigens with the greatest quantity of staminate flower production through the entire season were ‘Sidekick’ and ‘SP1’. The lowest number of staminate flowers was produced by ‘TP91’ and ‘TPS92’. Based on fruit quality characteristics and production, pollenizers currently or possibly marketed for consumption include ‘Mickylee’, ‘SF800’, ‘Minipol’, ‘Jenny’, and ‘Pinnacle’. The remaining cultigens evaluated in this study should be used strictly as pollenizers based on fruit quality. Arrangement of diploid pollenizers in a commercial planting of triploid watermelons is an important consideration depending on plant vegetative development. Based on staminate flower production, cultigens with higher staminate flower production are potentially superior pollenizers and may lead to improved triploid quality and production. Furthermore, pollenizer selection by fruit characteristics should include a rind pattern easily distinguished from triploid fruit in the field.

Effects of Air Temperature at the Seedling Stage and Pollination on the Development of Pistillate Flowers and Fruit Set in Cucumbers

The effects of high (day/night=30/25°C; H) and low (23/17°C; L) air temperatures on the development of pistillate flowers (PFs) during the seedling stage were clarified in 7 cucumber cultivars (Cucumis sativus L.) in order to identify potential high-yield cultivars in summer. Most of the cultivars developed nodes at a higher rate with H treatment than with the L treatment; however, the number of PF nodes and the total number of PFs on a plant were decreased with the H treatment in ‘028’ (multi-pistillate monoecious cultivar), ‘NK×AN8’ (mono- or di-pistillate gynoecious cultivar) and ‘Toyooka’ (multi-pistillate gynoecious cultivar). With H treatment, ‘028’ and ‘NK×AN8’ bore one PF or less per node, while ‘Toyooka’ produced 1.7 PFs per node. When the ‘028’ and ‘NK×AN8’ cultivars were grown in spring and summer, the PF numbers per PF node during summer were lower in the ‘028’ cultivar but not in ‘NK×AN8’. The fruit abortion rate was higher in summer in both cultivars, and it was reduced slightly by pollination. This study suggests that gynoecious cultivars could achieve a high yield in summer within a short growing period because they bear more PFs per node than multi-pistillate cultivars, and the effect of pollination on fruit abortion was too small to realize a high yield in summer.

Influence of weather at time of pollination on acorn production of Quercus alba and Quercus velutina

Pistillate flower development and acorn production were observed in small populations of white oak (Quercus alba L.) and black oak (Quercus velutina Lam.) in central Missouri from 1990 to 1997. There were significant year-year differences in the size of flower crops for both species and significant tree-tree differences in black oak. About 7% of the white oak flowers matured into acorns; most flowers aborted by early July, just after fertilization. About 12% of the black oak flowers matured into acorns, but some individual trees never or rarely produced a mature acorn. The number of fertilized flowers in white oak and black oak in early July was positively correlated with acorn production. Over all trees and years, the number of flowers and acorns were significantly correlated. Acorn production varied in relation to weather variables during the time of pollination. Simple regression models were good predictors of white oak acorn production but not of black oak acorn production. Maximum temperature and the number of days with hail had negative effects on acorn production. The number of days of rain during the pollination period was positively correlated with flower survival in black oak but not with white oak.

Pistillate flower development in eastern black walnut

Preliminary observations of terminal bud development in eastern black walnut (Juglansnigra L. cv. Ogden) were made from midwinter through early May of 1987 using light microscopy. Flattened meristems, characteristic of pistillate flower initiation, were present in late February. Pistillate flower differentiation progressed significantly during early and mid-April, with sepal and ovule development being evident. Terminal bud swelling was clearly visible by the last week of April, and pistillate flowers were fully expanded by the first week of May. During the spring of 1988, a more detailed sequence of pistillate flower formation was recorded. In mid-April, pistillate flower meristems were clearly present and were enclosed in involucre tissue. Sepal development was also evident. By the end of April, a single pistil had emerged in the center of the meristem. As development continued, a single orthotropous ovule was formed and was surrounded by one integument. Concomitant with the growth of the ovule during early May, stigmatic regions enlarged, involutions developed, and vascular tissue became differentiated. Blooming occurred during the 2nd and 3rd weeks of May. During the 3rd and 4th weeks of May fertilized flowers with endosperm tissue were observed. In 1991, field observations of bud swell, catkin development, bud break, stem elongation, leaf expansion, and pistillate flower development were made to supplement the histological observations made in 1988. Overall, the developmental sequence of pistillate flower formation is similar to that of protandrus cultivars of English walnut (Juglansregia L.).

Initiation and development of pistillate flowers in Actinidia chinensis

Initiation and development of pistillate flowers in Actinidia chinensis Planch, cultivar ‘Hayward’ (kiwifruit, Chinese gooseberry) was followed using light and scanning electron microscopy. Results indicate that dormant buds contain undifferentiated primordia in the leaf axils. These primordia remain undifferentiated until shortly before bud break, approximately two months before full bloom, when the primordia become trilobed as bracts and lateral flower primordia are initiated. The lateral flowers often abort in this cultivar. Acropetal development of the terminal flower proceeds rapidly. Five to seven sepals are initiated, followed by a whorl of five to seven petals. Stamen initiation is centripetal and the anthers develop to produce inviable pollen. The central portion of the floral apex is converted into a large compound pistil with numerous hollow styles, each terminated by an open stigma.

Pistillate Flower Development and Fruit Growth in Some English Walnut Cultivars1

Abstract The time of initiation of pistillate flowers was determined for each of 7 cultivars of walnut (Juglans regia L.). Flower formation (flattened apex) was evident during the first 2 weeks of June for ‘Chico’, ‘Vina’, ‘Serr’, ‘Tehama’, and ‘Pedro’ and mid-July for ‘Hartley’ and ‘Franquette’. Initiation of floral parts also occurred at different times depending on the cultivar. Pistil development began in February for ‘Chico’ and in April for ‘Franquette’. Fertilization occurred throughout April for most of the cultivars, but in the middle of May for ‘Franquette’.

The Relationship between Pistillate Flower Development and Air Temperature in ‘Western’ Pecan1

Abstract Six stages of floral development were identified and related to air temperature in Carya illinoensis (Wang.) K. Koch, cv. Western. Initiation (the first microscopically visible evidence of floral primordia) was detected on April 4, 1973, after an accumulation of 537 heat units. On April 10 a total of 598 heat units were accumulated when 93% of the buds sampled had initiated pistillate flowers. Floral development occurred normally, uniformly, and in concert with the heat units accumulated.

Morphactin-Induced Parthenocarpy in the Cucumber

Parthenocarpy was induced in cucumber Cucumis sativus L. by foliar application of morphactin. Morphactin (chlorfluorenol) was most effective in inducing parthenocarpy when applied in the flowering stage, and the response was enhanced by prior treatment with Ethrel (2-chloroethylphosphonic acid). Morphactin stimulated pistillate flower development in a monoecious cultivar but did not modify sex expression of a gynoecious line.

Effects of Photoperiod on Sex Expression in Ambrosia trifida

1. Ambrosia trifida, a short-day plant, after starting growth on long day, was subjected to two, ten, and twenty photoinductive cycles at each of three photoperiods-15, 12, and 6 hours. Following this treatment, the plants were returned to a long-day bench to complete growth. 2. Rate of maturity was most rapid and yield of fruit was greatest in the plants exposed to twenty photoinductive cycles at the 12-hour photoperiod. 3. Sex expression as measured by development of pistillate flowers in the position usually occupied by staminate increased with increasing numbers of photoinductive cycles and decreasing lengths of photoperiod, being greatest in the plants exposed to twenty photoinductive cycles at the 6-hour photoperiod.