Flowering Patterns Research Articles

Impact of Nitrate and Ammonium Ratios on Flowering and Asexual Reproduction in the Everbearing Strawberry Cultivar Fragaria × ananassa Albion

Ever-bearing (EB) strawberries are long-day cultivars that show perpetual flowering behavior. Compared to June-bearing short-day cultivars, EB cultivars can initiate flowers with less dependency on light and temperature levels. This leads to a more consistent flowering and fruiting pattern, making EB cultivars favorable for areas with long growing seasons. However, this flowering pattern also brings significant challenges to open-field strawberry nurseries. Consistent flower development in EB cultivars frequently leads to increased labor cost for manual flower removal on nursery ground. The alteration of flowering behavior via fertilizer regimes could be a cost-effective tool for strawberry nurseries. However, while it is known that the source of nitrogen (N) impacts strawberry flowering, its effect on strawberry propagation rates needs further investigation. The objective of this study was to investigate the impact of nitrate (NO3−) to ammonium (NH4+) ratio on flower and daughter plant production in the EB strawberry cultivar ‘Albion’ (Fragaria × ananassa c.v. ‘Albion’). Strawberry plants were grown in a completely randomized design under greenhouse conditions (26.6 °C, 16 h photoperiod). Four treatments of NO3−:NH4+ were implemented: (1) 100%:0%; (2) 80%:20%; (3) 60%:40%; (4) 50%:50%. Strawberry plants fertilized with a 60%:40% NO3−:NH4+ ratio produced 17–31% fewer inflorescences than those fertilized with 100%:0% (8.8 ± 1.19) and 80%:20% (10.3 ± 1.85) ratios. The production of daughter plants remained similar in all four treatments. Our results show that increased ratios of ammonium in combination with decreased ratios of nitrate reduce flowering of EB strawberry cultivars, while propagation rates remain consistent. These results could potentially lead to the development of fertilizer regimes for strawberry nurseries to reduce flower production in EB cultivars.

Using local weather stations to generate growing degree‐day data to predict the flowering pattern of an annual bluegrass fairway in Michigan

AbstractSix 1‐yr observational studies were conducted from 2001 to 2006 at the Hancock Turfgrass Research Center in East Lansing, MI to characterize the timing, duration, and amplitude of annual bluegrass (AB) (Poa annua L.) seedhead emergence in a 10‐ to 15‐yr‐old AB fairway. The objective of this research was to collect data that could be used in the development of a growing degree‐day (GDD) model to predict AB seedhead emergence at other locations by using readily available weather station data. New GDD models were compared with previously published models. Plots were established on two adjacent perennial stands of AB maintained at 1.5 cm, receiving 0.5 to 0.6 cm of automatic daily irrigation throughout the growing season and 120 kg N ha–1 yr–1 from 2001 to 2006. The soil type is a Marlette sandy loam (fine‐loamy, mixed, semiactive, mesic Oxyaquic Glossudalf). Line intersects and visual estimations of seedhead cover were evaluated multiple times throughout the spring seedhead emergence period. A base temperature of –5 °C most accurately predicted the onset, peak duration, and completion of the AB seedhead emergence period for all 5 yr. The final model flowering rate = (–3.331599 × 10–6 × gdd2) + (6.968782 × 10–3 × gdd) + –2.841894, accurately predicted (R2 = .64) flowering stages of an AB fairway turf over 6 yr in Michigan.

Asynchronous flowering patterns in saguaro cacti (Carnegiea gigantea)

AbstractThe saguaro cactus (Carnegiea gigantea [Engelm.] Britton & Rose) is a keystone species endemic to the Sonoran Desert of northern Mexico and the southwestern United States. The saguaro produces large white flowers near its stem apex (crown) during April–June, which bloom at night and close the following day. In 1924, Duncan Johnson reported that saguaro floral buds are likely to have an asymmetrical distribution in which buds occur in higher densities on the eastern half of a plant's crown. Using technology not available to Johnson, we tested his observations to determine whether flowers are asymmetrically distributed using repeat photography. We also tested whether there is a seasonal pattern of flowering that may explain Johnson’s observations. We tracked intra‐individual flowering phenology of 20 saguaros and measured 2372 flowers across two reproductive seasons in Saguaro National Park, Tucson, Arizona. Flowers first appeared on the east side of all saguaro crowns at the start of the reproductive season, and then spread radially in a counterclockwise direction as the season progressed. In contrast to previous reports, saguaro flowers were consistently more abundant on the northern part of the crown than in the eastern part. To our knowledge, this study is the first to document a seasonal, counterclockwise pattern of asynchronous flowering in saguaro or any angiosperm. We discuss potential drivers of this phenomenon as well as implications for saguaros responding to climate change.

Effects of Exogenous Gibberellic Acid in Huanglongbing-affected Sweet Orange Trees under Florida Conditions – I. Flower Bud Emergence and Flower Formation

Under Florida conditions, sweet orange (Citrus sinensis) affected by Huanglongbing {HLB [Candidatus Liberibacter asiaticus (CLas)]} frequently exhibits irregular flowering patterns, including off-season flowering and prolonged bloom period. Such patterns can increase the opportunity for temporal and spatial proliferation of pathogens that infect flower petals, including the fungal causal agent for postbloom fruit drop (PFD) Colletotrichum acutatum J.H. Simmonds. For the development of strategies to manipulate flowering, the effects of floral inhibitor gibberellic acid (GA3) sprayed monthly at full- and half-strength rates (49 and 25 g·ha−1, or 33 and 17 mg·L−1, respectively) with different regimens, starting from September and ending in November, December, or January, on the pattern of spring bloom were evaluated in field-grown HLB-affected ‘Valencia’ sweet orange at two locations in subsequent February through April for two separate years in this study. To further examine whether GA3 effects on flowering patterns vary in different cultivars, early-maturing ‘Navel’ sweet orange trees receiving no GA3 or full-strength GA3 monthly in September through January were included. Overall, for ‘Valencia’ sweet orange, monthly applications of GA3 at 49 g·ha−1 from September to December not only minimized the incidence of scattered emergence of flower buds and open flowers before the major bloom but also shortened the duration of flowering, compared with the untreated control trees. In addition, exogenous GA3 led to decreased leaf flowering locus t (FT) expression starting in December, as well as reduced expression of its downstream flower genes in buds during later months. When applied monthly from September through January at 49 g·ha−1, similar influences of exogenous GA3 on repressing flower bud formation and compressing bloom period were observed in ‘Navel’ sweet orange. These results suggest that by effectively manipulating flowering in HLB-affected sweet orange trees under the Florida climate conditions, exogenous GA3 may be used to reduce early sporadic flowering and thereby shorten the window of C. acutatum infection that causes loss in fruit production.

Plant age at the time of ozone exposure affects flowering patterns, biotic interactions and reproduction of wild mustard

Exposure of plants to environmental stressors can modify their metabolism, interactions with other organisms and reproductive success. Tropospheric ozone is a source of plant stress. We investigated how an acute exposure to ozone at different times of plant development affects reproductive performance, as well as the flowering patterns and the interactions with pollinators and herbivores, of wild mustard plants. The number of open flowers was higher on plants exposed to ozone at earlier ages than on the respective controls, while plants exposed at later ages showed a tendency for decreased number of open flowers. The changes in the number of flowers provided a good explanation for the ozone-induced effects on reproductive performance and on pollinator visitation. Ozone exposure at earlier ages also led to either earlier or extended flowering periods. Moreover, ozone tended to increase herbivore abundance, with responses depending on herbivore taxa and the plant age at the time of ozone exposure. These results suggest that the effects of ozone exposure depend on the developmental stage of the plant, affecting the flowering patterns in different directions, with consequences for pollination and reproduction of annual crops and wild species.

Modeling flower pigmentation patterns

Although many simulation models of natural phenomena have been developed to date, little attention was given to a major contributor to the beauty of nature: the colorful patterns of flowers. We survey typical patterns and propose methods for simulating them inspired by the current understanding of the biology of floral patterning. The patterns are generated directly on geometric models of flowers, using different combinations of key mathematical models of morphogenesis: vascular patterning, positional information, reaction-diffusion, and random pattern generation. The integration of these models makes it possible to capture a wide range of the flower pigmentation patterns observed in nature.

Genetic insights into the regulatory pathways for continuous flowering in a unique orchid Arundina graminifolia

BackgroundManipulation of flowering time and frequency of blooming is key to enhancing the ornamental value of orchids. Arundina graminifolia is a unique orchid that flowers year round, although the molecular basis of this flowering pattern remains poorly understood.ResultsWe compared the A. graminifolia transcriptome across tissue types and floral developmental stages to elucidate important genetic regulators of flowering and hormones. Clustering analyses identified modules specific to floral transition and floral morphogenesis, providing a set of candidate regulators for the floral initiation and timing. Among candidate floral homeotic genes, the expression of two FT genes was positively correlated with flower development. Assessment of the endogenous hormone levels and qRT-PCR analysis of 32 pathway-responsive genes supported a role for the regulatory networks in floral bud control in A. graminifolia. Moreover, WGCNA showed that flowering control can be delineated by modules of coexpressed genes; especially, MEgreen presented group of genes specific to flowering.ConclusionsCandidate gene selection coupled with hormonal regulators brings a robust source to understand the intricate molecular regulation of flowering in precious orchids.

Illumination of Hanjuang Flower Patterns in Mushaf Qur'an Sundawi

This research is motivated by the illumination of the Hanjuang floral motif in the Sundawi Qur'anic manuscript. Meanwhile, in general, manuscripts that are often circulated in good print from middle eastern Indonesia use illumination with a geometric Islamic pattern. The purpose of this study is to explain the Sundawi Qur'an as a whole related to the formulation of the Hanjuang floral motif illumination concept, an explanation of the Hanjuang floral motif illumination, and the relevance of the Hanjuang floral motif illumination to the Sundawi Qur'anic Mushaf. This study uses a qualitative method with an aesthetic approach that systematically describes the things that are the focus of the research. The data collection technique used in this research is library research and field research using the interview method with informants. The results of this study found that the formulation of the concept of illumination of the Hanjuang floral motif with the Sundawi Qur'anic Mushaf is one of the characteristics of West Java plants or flora and also as a means of introducing West Javanese ornaments in Sundawi Qur'anic manuscripts, this illumination will have an impact on the synergy between the decorative motifs and the writings on the Sundawi Qur'anic manuscripts verse and the Hanjuang motifs affect the reader's enthusiasm to continue reading the Qur'an

A Strobilanthes (Acanthaceae) miscellany

SummaryThis paper presents miscellaneous, previously unpublished results arising from the authors’ research into Strobilanthes. S. moylaniae J.R.I.Wood & Scotland from New Guinea and S. dengii J.R.I.Wood & Scotland from Sumatra are proposed as new species, while an unnamed species is described from Sumba Island in Indonesia in the hope that it might be rediscovered. A new subspecies, subsp. subovata J.R.I.Wood & Scotland is described for S. timorensis Nees, while attention is drawn to its plietesial flowering pattern. The new combinations S. benculensis (Bremek.) J.R.I.Wood & Scotland, S. wetarensis (Bremek.) J.R.I.Wood & Scotland, S. javanica (Bremek.) J.R.I.Wood & Scotland and S. serpens (Nees) J.R.I. Wood & Scotland are made. Typification is clarified and where appropriate lectotypes are designated for Hemigraphis hispidula Craib, Lepidagathis setigera Blume, Ruellia crispa L., R. sabiniana Lindl., Strobilanthes duclouxii Benoist, S. erecta C.B.Clarke, S. flava Kurz, S. forrestii Diels, S. scabra Nees, S. secunda T.Anderson and S. thomsonii T.Anderson.

A nectar oasis for urban Glossophaginae bats: Temporal resource dynamics of the chiropterophilous Crescentia cujete (Bignoniaceae)

Pollinator-friendly plants are often a necessary component of the management of urban ecosystem that aim to reduce the impact of the artificial urban matrix on natural pollinator populations. Nectarivorous bats are neglected components of the urban pollinator community and there is a paucity of assessments on pollinator-friendly plants that may provide urban bats with reliable, year-long resources. Crescentia cujete is a bat-pollinated Bignoniaceae with very distinctive chiropterophilous features that is often used as an ornamental species in tropical urban areas worldwide. Its flowers are large and produce copious amounts of nectar, which accumulates in the flower’s storage-shaped flowers. Thus, the species is a potential bat-friendly urban plant. We assessed the species’ year-round flower emission and nightly nectar production dynamics in a green area in northeastern Brazil, and described the behavior of its floral visitors. C. cujete showed a steady, year-round flowering pattern, with no significant seasonality. Its flowers secreted copious amounts of diluted nectar and were visited exclusively by the Pallas long-tongued bat Glossophaga soricina throughout the night at high visiting frequencies, delivering successive visits to individual flowers spaced by short intervals. Our results suggest overexploitation of floral resources from C. cujete by urban bats. Moreover, its continuous flowering and copious nectar production may become a reliable resource in an artificial environment generally lacking bat-pollinated plants, thus mitigating the effects of food shortage for urban nectar bats.

Effects of Temperature and Photoperiod on the Flower Potential in Everbearing Strawberry as Evaluated by Meristem Dissection

The growing interest in using everbearing (EB) strawberry cultivars to extend the cultivation period has faced some challenges. These include poor runner production due to its perpetual flowering nature; irregular flowering behavior and extended periods of high temperature have caused floral inhibition and reduced yield. As flowering is an interplay between temperature and photoperiod, it is important to investigate the effects of this interaction on the cultivation. Therefore, this study used meristem dissection as a tool to study the effect of temperature and photoperiod on meristem development. Tray plants of two EB strawberry cultivars ‘Florentina’ and ‘Favori’ were grown at 20 °C, 25 °C, and 30 °C under short day (SD) conditions, and subsequently at 20 °C under long day (LD) conditions. The meristem development was analysed every 6 weeks for a 15-week period in SD and for 14 weeks in LD conditions using meristem dissection. The plants showed similar flowering patterns to previously studied everbearing cultivars, which was qualitative LD plants at high temperatures and quantitative LD plants at lower temperatures. Our results show that meristem dissection can be used to determine the temperature and photoperiodic effect on meristem development, and for the occurrence of cropping peaks, and can therefore be used to decide the environmental input and to evaluate yield potential.

Application of Flower and Bird Patterns in Modern Makeup and Hair from the Perspective of Design Culture

Under the background of the vigorous development of various cultural and artistic forms, the traditional patterns that can express the unique charm of Chinese national culture have become an important material for modern design. Traditional patterns not only have unique decorative functions, but also represent the spirit of traditional culture. Among them, flower and bird patterns are also precipitated by history. It is worth exploring how to combine the flower and bird patterns with the aesthetics of the times, and how to integrate the traditional flower and bird patterns with the nature of the times. Starting with the formation and development of flower and bird patterns, this paper analyzes the historical, cultural and aesthetic attributes of flower and bird patterns from the perspective of design culture, and expounds the application of flower and bird patterns in makeup and hair in various historical dynasties. With the development of the times, the application of flower and bird patterns in modern makeup and hair should be both national and in line with the aesthetic requirements of modern people.

Flowering segregation and pollinator distinctiveness contribute to coexistence in an extremely generalist plant group

Background Flowering time determines potential plant mates, and it is related to gene flow within and among plant populations arising from different selective forces and interspecific interactions between plants with similar pollination niches. However, these effects on flowering phenology of plants with generalist pollination systems have received little attention and hence our knowledge of the contribution of generalised pollination systems on the evolution of adaptative traits, such as the flowering time contains lacunae. Aims To verify the effective contribution of interspecific plant interactions in a generalised pollination system to the structuring of flowering phenology. Methods We recorded the reproductive phenophases of four Baccharis species in a subtropical grassland. We evaluated their flowering patterns by a niche overlap index and compared it with a null model. We used ecological network metrics from insect visitors recorded to determine the pollinator network structure. Results A staggered flowering pattern and distinctiveness of insect pollinators with non-signal of modularity and a variation in the Baccharis-pollinators network structure throughout the year were observed. The distinctiveness on pollinators with a strong bee-dependence added to temporal divergence on flowering among the species leads to no negative effects on fruit set. Conclusion The temporal segregation on flowering peaks and low pollinator similarity appear to underlie to coexistence of Baccharis species studied in southern Brazil.

Comparative transcriptome analysis identified important genes and regulatory pathways for flower color variation in Paphiopedilum hirsutissimum

BackgroundPaphiopedilum hirsutissimum is a member of Orchidaceae family that is famous for its ornamental value around the globe, it is vulnerable due to over-exploitation and was listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, which prevents its trade across borders. Variation in flower color that gives rise to different flower patterns is a major trait contributing to its high ornamental value. However, the molecular mechanism underlying color formation in P. hirsutissimum still remains unexplored. In the present study, we exploited natural variation in petal and labellum color of Paphiopedilum plants and used comparative transcriptome analysis as well as pigment measurements to explore the important genes, metabolites and regulatory pathways linked to flower color variation in P. hirsutissimum.ResultWe observed that reduced anthocyanin and flavonoid contents along with slightly higher carotenoids are responsible for albino flower phenotype. Comparative transcriptome analysis identified 3287 differentially expressed genes (DEGs) among normal and albino labellum, and 3634 DEGs between normal and albino petals. Two genes encoding for flavanone 3-hydroxylase (F3H) and one gene encoding for chalcone synthase (CHS) were strongly downregulated in albino labellum and petals compared to normal flowers. As both F3H and CHS catalyze essentially important steps in anthocyanin biosynthesis pathway, downregulation of these genes is probably leading to albino flower phenotype via down-accumulation of anthocyanins. However, we observed the downregulation of major carotenoid biosynthesis genes including VDE, NCED and ABA2 which was inconsistent with the increased carotenoid accumulation in albino flowers, suggesting that carotenoid accumulation was probably controlled at post-transcriptional or translational level. In addition, we identified several key transcription factors (MYB73, MYB61, bHLH14, bHLH106, MADS-SOC1, AP2/ERF1, ERF26 and ERF87) that may regulate structural genes involved in flower color formation in P. hirsutissimum. Importantly, over-expression of some of these candidate TFs increased anthocyanin accumulation in tobacco leaves which provided important evidence for the role of these TFs in flower color formation probably via regulating key structural genes of the anthocyanin pathway.ConclusionThe genes identified here could be potential targets for breeding P. hirsutissimum with different flower color patterns by manipulating the anthocyanin and carotenoid biosynthesis pathways.

Massive investments in flowers were in vain: Mass flowering after a century did not bear fruit in the bamboo Phyllostachys nigra var. henonis

AbstractPhyllostachys nigra var. henonis (Poales: Poaceae) is a tall, temperate bamboo species that has a long monocarpic life history with a flowering interval of around 120 years that is often conspicuously synchronized across a wide geographical area. Interestingly, observations of the last major flowering event, which was about a century ago, suggested that mature seeds were rarely produced as a consequence. As this bamboo has recently started flowering across Japan after a century of silence, we seek to understand its reproductive strategy by quantifying the following four issues: (1) flowering patterns within stands, (2) the presence or absence of mature seeds, (3) resource allocations to reproductive parts, and (4) asexual regrowth capacity after mass flowering. We conducted field surveys at five flowering bamboo stands in Japan. At each, many spikelets were found, but neither mature seeds nor seedlings. During the mass flowering, large amounts of resources were allocated to reproductive parts, accounting for 57% of the aboveground nitrogen pool and 63% of the aboveground phosphorus pool. These results indicate that the accumulated resources were used for flowers, but not for seed production, and thus apparently in vain. While most of the flowering ramets appeared to die, dwarf ramets (mostly less than 1 m in height) typically regenerated from the remaining belowground rhizomes and seem to be critical for maintaining the bamboo stands. This apparently inefficient sexual reproductive strategy still exists (without local extinction) perhaps due to the vigorous clonal growth system and to human‐assisted distribution.

Reproductive biology of Vatica venulosa Blume (Dipterocarpaceae)

Abstract. Widjaya AH, Latifah D, Hardwick KA, Suhartanto MR, Palupi ER. 2021. Reproductive biology of Vatica venulosa Blume (Dipterocarpaceae). Biodiversitas 22: 4327-4337. Vatica venulosa Blume is categorized as Critically Endangered A1c ver 2.3, according to the IUCN Red List. A study of the reproductive biology of V. venulosa Blume was carried out in August 2019-February 2020 at the Research Center for Plant Conservation and Botanic Gardens, Bogor, Indonesia. The research observed flower morphology, flower development, type of pollination, fruit and seed structures. V. venulosa is categorized as having a sub-annual flowering pattern. The flowering phenology of V. venulosa from flower bud emergence until fruit senescence takes about 6 months. The flower is hermaphroditic, with position of the pistil is higher/longer than the stamen; and pollen was released prior to stigma being receptive (protandrous). V. venulosa is a cross-pollinated plant, the flower visitors are insect nymphs of Thrips sp. (Thysanoptera: Thripidae), which are white and 1-1.5 mm in size. The percentage of blooming flowers was 32.3-37.9%, fruit set 10.9 %-12.6%. Seed physiological maturity is reached at the age of 101±3-106±3 days after the flowers bloom when the wings are yellow green or green orange in color. V. venulosa seed is a non endospermous seed, and the cotyledons are composed mainly of small clumps of starch, being 42.5% carbohydrate.

Use of timelapse photography to determine flower opening time and pattern in banana (Musa spp.) for efficient hand pollination

Sterility and low seed set in bananas is the main challenge to their conventional genetic improvement. The first step to seed set in a banana breeding program depends on pollination at the right time to ensure effective fertilization. This study aimed at determining bract opening time (BOT) to enhance efficient pollination and seed set in bananas. A Nikon D810 digital camera was set-up to take pictures of growing banana inflorescences at five-minute intervals and time-lapse movies were developed at a speed of 30 frames per second to allow real-time monitoring of BOT. Genotypes studied included wild banana (1), Mchare (2), Matooke (4), Matooke hybrid (1), and plantain (1). Events of bract opening initiated by bract lift for female flowers (P < 0.01) started at 16:32 h and at 18:54 h for male flowers. Start of bract rolling was at 18:51 h among female flowers (P < 0.001) and 20:48 h for male flowers. Bracts ended rolling at 02:33 h and 01:16 h for female and flowers respectively (P < 0.05). Total time of bract opening (from lift to end of rolling) for female flowers was significantly longer than that of male flowers (P < 0.001). On average, the number of bracts subtending female flowers opening increased from one on the first day, to between one and four on the fourth day. The number regressed to one bract on day eight before start of opening of bracts subtending male flowers. There was a longer opening interval between bracts subtending female and male flowers constituting spatial and temporal separation. Bract rolling increased from partial to complete rolling from proximal to the distal end of the inflorescence among female flower. On the other hand, bracts subtending male flowers completely rolled. Differences in BOT of genotypes with the same reference time of assessment may be partly responsible for variable fertility. Hand pollination time between 07:00 and 10:00 h is slightly late thus an early feasible time should be tried.

Expression and Functional Analyses of Nymphaea caerulea MADS-Box Genes Contribute to Clarify the Complex Flower Patterning of Water Lilies.

Nymphaeaceae are early diverging angiosperms with large flowers characterized by showy petals and stamens not clearly whorled but presenting a gradual morphological transition from the outer elements to the inner stamens. Such flower structure makes these plant species relevant for studying flower evolution. MADS-domain transcription factors are crucial components of the molecular network that controls flower development. We therefore isolated and characterized MADS-box genes from the water lily Nymphaea caerulea. RNA-seq experiments on floral buds have been performed to obtain the transcript sequences of floral organ identity MADS-box genes. Maximum Likelihood phylogenetic analyses confirmed their belonging to specific MADS-box gene subfamilies. Their expression was quantified by RT-qPCR in all floral organs at two stages of development. Protein interactions among these transcription factors were investigated by yeast-two-hybrid assays. We found especially interesting the involvement of two different AGAMOUS-like genes (NycAG1 and NycAG2) in the water lily floral components. They were therefore functionally characterized by complementing Arabidopsis ag and shp1 shp2 mutants. The expression analysis of MADS-box genes across flower development in N. caerulea described a complex scenario made of numerous genes in numerous floral components. Their expression profiles in some cases were in line with what was expected from the ABC model of flower development and its extensions, while in other cases presented new and interesting gene expression patterns, as for instance the involvement of NycAGL6 and NycFL. Although sharing a high level of sequence similarity, the two AGAMOUS-like genes NycAG1 and NycAG2 could have undergone subfunctionalization or neofunctionalization, as only one of them could partially restore the euAG function in Arabidopsis ag-3 mutants. The hereby illustrated N. caerulea MADS-box gene expression pattern might mirror the morphological transition from the outer to the inner floral organs, and the presence of transition organs such as the petaloid stamens. This study is intended to broaden knowledge on the role and evolution of floral organ identity genes and the genetic mechanisms causing biodiversity in angiosperm flowers.

Effect of Zone and Climate on Yields, Quality and Ripening Characteristics of Montecristo Bananas Grown in Puerto Rico

A study was conducted to determine the effect of zone and climate on yields, ripening characteristics and quality of Montecristo bananas. Experimental plots were established at the Fortuna Substation on the southern coast of Puerto Rico at sea level, and the Adjuntas Substation located in the humid mountainous area at an elevation of 1,800 feet. In plots planted monthly throughout the year, the interval from planting to flowering ranged at the Adjuntas Substation from 371 to 448 days and from 319 to 388 days at the Fortuna Substation. At Fortuna, the length of the flowering period ranged from 120 to 147 days, while at Adjuntas it ranged from 107 to 200 days. A direct relationship was observed at Adjuntas between the length of the flowering period and time of planting. The flowering pattern of the combined monthly plots was different for the two zones. Two flowering cycles were observed at Adjuntas, with the highest percentage of plants flowering from June to December. Although three flowering cycles were observed at Fortuna, the distribution was similar to a normal frequency distribution. Bunch development was much slower at Adjuntas than at Fortuna. The age for harvesting at a given stage of development varied with the time of flowering, but this relationship was more marked at Adjuntas than at Fortuna. The fruit harvested at Adjuntas was quite different in characteristics from the fruit harvested at Fortuna. The bunches were heavier and the fruit weighed more. The bunches also had more hands and more fruit than those harvested at Fortuna. At Adjuntas, the weight of the bunch remained fairly constant throughout the year, while at Adjuntas the weight of the bunch varied with the month of flowering. The weight of the fingers at both locations varied with the time of flowering while the number of fruit per bunch at Fortuna varied only slightly throughout the year. Because the seed material used in these studies was obtained from two farms in the Adjuntas region, another set of experiments was conducted to study the behavior of the Montecristo bananas produced from seed from the experimental plots from each Substation when planted on the other. The results from these experiment showed that the seed material used in our previous studies were of uniform character and that differences observed in flowering patterns, yields, fruit quality and other characteristics were due to the effect of ecological conditions and not to clonal variation. The fruit from both locations when processed into purees gave products of good quality. Fruit from Adjuntas produced purees of a more pronounced yellow color and the flavor was better than fruit from Fortuna. From the standpoint of fresh fruit quality, however, the fruit from Fortuna was better than the fruit from Adjuntas. The fruit from Fortuna had better ripening characteristics, ripening more evenly and with a more attractive yellow color, than the fruit from Adjuntas.

The de novo transcriptome identifies important zinc finger signatures associated with flowering in the orchid Arundina graminifolia

Orchids take years to produce the most precious and expensive flowers. Continuous flowering is a rare characteristic of bamboo orchid (Arundina graminifolia). Therefore, finding genetic regulators of this flowering pattern can set new directions for other orchids. Present study demonstrates transcriptome analysis to identify a number of zinc finger transcription factors (ZF TFs) from five stages of flower development and four tissue types. About 480 DEGs were annotated to the zinc finger category, which may involve multiple signaling pathways for flowering control. The highest number of ZF TFs belonged to CCCH domain, followed by BED and INDETERMINATE. Some important ZF TFs were found to control the flowering genes at transcriptional levels. LATE and B-box ZFs respond to photoperiod and hormone signaling. MAD1 and SUF4 control flowering time through FLC. BZR1 and ELF6 possibly respond to vernalization pathway and HUA1 controls flowering through AGAMOUS pathway. WGCNA-based ZF candidates BBX22 and BBX24 involve circadian and hormonal pathways in association with floral integrators to regulate flowering time in A. graminifolia. Thus, our ZF mining can do a great deal to understand the molecular mechanism of continuous flowering in A. graminifolia.