Floret Opening Research Articles

Morphophysiological adaptations and fragrance profile analysis of two relocated orchid species

This study investigates the morpho-physiological adaptations and fragrance profiles of 2 relocated orchid species, Cattleya aclandiae x Brassavola Little star (V1) and Dendrobium var. Meesangnil (V2), following their translocation from Nagercoil to Coimbatore, India. The research aims to elucidate the mechanisms underlying successful acclimatization of these fragrant orchids to a new environment, with implications for horticulture, conservation and therapeutic applications. Comprehensive analyses were conducted on vegetative growth parameters, flowering characteristics, physiological responses and volatile organic compound (VOC) profiles. Morphological assessments revealed distinct adaptive strategies between the 2 species, with Dendrobium exhibiting superior vertical growth (39.13 cm) and leaf production (9 leaves/plant), while Cattleya developed larger leaves (30.483 cm length, 7.178 cm breadth) and longer internodes (5.061 cm). Flowering characteristics also differed significantly, with Cattleya demonstrating earlier spike emergence and floret opening. Physiological analyses using a CI-340 Handheld Photosynthesis System showed higher photosynthetic rates, transpiration rates and stomatal conductance in Dendrobium, suggesting a more resource-acquisitive strategy. Gas chromatography-mass spectrometry (GC-MS) analysis identified unique VOC profiles for each species, with 30 compounds detected in both varieties, including notable compounds such as n-Hexadecanoic acid, Octadecanoic acid and beta-Sitosterol. The study also explored potential applications in therapeutic horticulture, highlighting the diverse sensory and educational value of these orchid species. This comprehensive analysis of morphological, physiological and biochemical adaptations provides valuable insights into orchid acclimation processes and their potential for conservation and horticultural applications, contributing to our understanding of plant adaptability in the face of environmental changes and offering a foundation for future studies on orchid biology, ecology and therapeutic uses.

A jasmonate-mediated regulatory network modulates diurnal floret opening time in rice.

Diurnal floret opening time (DFOT) is a pivotal trait for successful fertilization and hybrid breeding in rice. However, the molecular mechanism underlying this trait is poorly understood in rice. In this study, we combined the cytological, genetic and molecular studies to demonstrate that jasmonic acid (JA) regulates DFOT in rice through modulating the turgor and osmotic pressure of the lodicules. We show that lodicules undergo dramatic morphologic changes, accompanied by changes in water and sugar contents during the process of floret opening. Consistently, a large set of genes associated with cell osmolality and cell wall remodeling exhibits distinct expression profiles at different time points in our time-course transcriptomes of lodicules. Notably, a group of JA biosynthesis and signaling genes is continuously upregulated, accompanied by a gradual increase in JA accumulation as floret opening approaching. Furthermore, we demonstrate that the JA biosynthesis gene OsAOS1 is required for endogenous JA biosynthesis in lodicules and promoting rice DFOT. Moreover, OsMYC2, a master regulator of JA signaling, regulates rice DFOT by directly activating OsAOS1, OsSWEET4, OsPIP2;2 and OsXTH9. Collectively, our findings establish a core regulatory network mediated by JA for modulating rice DFOT and provide effective gene targets for the genetic improvement of DFOT in rice.

Effect of Chlormequat (CCC) and Gibberellin (GA3) on Growth and Flowering of Tuberose (Polianthes tuberosa L.) Var. Mexican Single

The experiment was conducted at Experimental Farm, Department of Agriculture, Mata Gujri College, Fatehgarh Sahib, Punjab during summer season 2022-2023 to study the effect of growth regulators on growth and flowering of Tuberose (Polianthes tuberosa) var. Mexican Single. The experiment was laid out in randomized block design with seven treatments such as no - growth regulators(Control),GA3@50ppm, GA3@ 100ppm, GA3@150ppm, CCC@1250ppm, CCC @ 1500ppm and CCC @1750ppm and the treatments were replicated thrice. Observation were recorded for vegetative and flowering parameters. Maximum plant canopy was recorded with CCC @ 1750ppm. Maximum leaf size was found in GA3 @ 150ppm.Flowering parameters such as early opening of first florets and Maximum spike length was found with GA3@150ppm. Diameter of spike and diameter of first floret recorded maximum with CCC@ 1500ppm. Total water uptake (ml) by flowers during post harvest found to be maximum in CCC@ 1750ppm.Therefore, GA3 @ 150ppm and CCC@ 1500ppm can be recommended for growth and flowering of Tuberose.

Molecular basis of differential sensitivity to MeJA in floret opening between indica and japonica rice

Molecular basis of differential sensitivity to MeJA in floret opening between indica and japonica rice

To open early or late: Decoding the mystery of diurnal floret opening time in rice

To open early or late: Decoding the mystery of diurnal floret opening time in rice

Natural variation in OsMYB8 confers diurnal floret opening time divergence between indica and japonica subspecies

The inter-subspecific indica-japonica hybrid rice confer potential higher yield than the widely used indica-indica intra-subspecific hybrid rice. Nevertheless, the utilization of this strong heterosis is currently hindered by asynchronous diurnal floret opening time (DFOT) of indica and japonica parental lines. Here, we identify OsMYB8 as a key regulator of rice DFOT. OsMYB8 induces the transcription of JA-Ile synthetase OsJAR1, thereby regulating the expression of genes related to cell osmolality and cell wall remodeling in lodicules to promote floret opening. Natural variations of OsMYB8 promoter contribute to its differential expression, thus differential transcription of OsJAR1 and accumulation of JA-Ile in lodicules of indica and japonica subspecies. Furthermore, introgression of the indica haplotype of OsMYB8 into japonica effectively promotes DFOT in japonica. Our findings reveal an OsMYB8-OsJAR1 module that regulates differential DFOT in indica and japonica, and provide a strategy for breeding early DFOT japonica to facilitate breeding of indica-japonica hybrids.

Effect of ionizing radiated gladiolus (Gladiolus grandifloras) on vase life attributes of various cultivars

An experiment was conducted during winter (rabi) seasons of 2018–19 (vM2), 2019–20 (vM3) and 2020–21(vM4) at Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand to evaluate the effect of gamma rays treated gladiolus (Gladiolus grandiflorus Andrews) on the post-harvest of different varieties along with their interaction for different qualitative traits The result showed that Praha was best cultivars for days to first floret opening, highest number of florets per spikes, highest number of open florets per spikes, rachis length and weight loss followed by cultivar Candyman for highest diameter of lowest floret, highest vase life and highest water uptake by spikes. Among the different gamma doses, the minimum days to first floret opening, the highest diameter of first floret, the days to first floret withering, the number of florets, the number of open florets, the rachis length, vase life, water uptake by spikes and the weight loss were recorded in non-irradiated corms. Among interaction, V2G0 (Praha + control) showed best result for days to first floret opening, total number of florets per spike, total number of open florets/spike and rachis length. Most important characters, vase life was positively correlated with rachis length at 5.0 and 6.0 Kr respectively, total number of florets/spike and total number of open florets/spike at 5.0 Kr. Study concluded that gamma rays affect the qualitative as well quantitative traits of gladiolus and do not have positive effect on vase life attributes.

Improvement in Vase Life of Gladiolus Cut Flowers Using Different Holding Solutions of Sodium Nitroprusside and of Salicylic Acid

Gladiolus (Gladiolus hybridus Hort.) is one of the most important commercial ornamentals cut flower used in the floriculture industry. Among cut flowers, gladiolus is popular for its glamour, perfection and attractive colorful spikes. The longevity of cut flowers is one of the main challenges of florists to gain consumers attention towards its marketing. In present investigation, we tried two chemicals viz. Sodium nitroprusside (SNP, a NO donor) and Salicylic Acid (SA, a signaling molecule) in different concentration combinations and observed their effect on gladiolus flowers vase life of two varieties viz. Pusa Shanti and Pusa Chandni. Spikes treated with T7 (SA 150 mg/L), in Pusa Shanti and T2 (SNP 100 mg/L), in Pusa Chandni was observed effective treatments than others and showed better performance of vase life, days after basal florets open, maximum size of florets, solution uptake, florets opening and maximum time taken for the vase deterioration and it helped to improve the postharvest quality of gladiolus spikes by influencing various morphological and physiological attributes of gladiolus vase. Through the present study we are able to know the role of Sodium nitroprusside and Salicylic acid to enhance the vase life of cut flower of Gladiolus.

FLOWER QUALITY AND VASE LIFE OF GLADIOLUS AS AFFECTED BY HORMONES

An experiment was conducted at the Floriculture field of Horticulture Research Centre, Gazipur during Rabi season of 2021-22 to find out the effect of preharvest spray of different hormones (GA3, SA and BA) at different concentrations on flower and vase life of gladiolus. The experiment was laid out in a Randomized CompleteBlock design with three replications. The treatments were T1=GA3 @ 100 ppm, T2=GA3 @ 200 ppm, T3=GA3 @ 300 ppm, T4=SA@ 100 ppm, T5=SA @ 200 ppm, T6=SA @ 300 ppm, T7=BA @ 100 ppm, T8=BA @ 200 ppm, T9=BA @ 300 ppm and T10 = Control (fresh water). Healthy corms of gladiolus having a diameter of about 5.0 cm were used as plantingmaterial. The aqueoussolution of GA3 (100, 200 and 300 ppm), SA (100, 200 and 300 ppm) and BA (100, 200 and 300 ppm) along with control (fresh water) were applied twice on the flower plants at three and six leaves stage. Flowering parameters of plants as well as vase life of flowers were significantly influenced by the application of hormones. Among all the treatments, application of SA @ 100 ppm was recorded to be an outstanding treatment in improving floraland vase qualityattributes i.e. highestspike (78.5 cm) and rachislength (52.8 cm), maximum floret number/spike (14.5), biggest floret diameter (10.0 cm) and early spike initiation (65 days) were observed as compared to control. The maximum floret opening (90%), highest water uptake (45.0 g) and maximum vase life (12 days) were also noted with SA @ 100 ppm in gladiolus.

Assessment of Vegetative, Floral and Corm Characteristics in Gladiolus Genotype at Malepatan, Pokhara, Nepal

Gladiolus (Gladiolus grandifloras L.), recognized for its bright, distinctively textured blossoms, is first commercially grown cut flower in Nepal. A study was carried out to assess vegetative, floral, and corm characteristics in gladiolus genotypes in Maltepatan, Pokhara. Twelve genotypes namely NGRV0130 (ARSDG-04), RARSLG-014-1.1, RARSLG-014-1.11, RARSLG-014-2.8, RARSLG-014-3.10(A), RARSLG-014-3.11, RARSLG-014-6.8, RARSLG-014-6.12, RARSLG-014-6.13, RARSLG-014-7.27(A), RARSLG-014-8.22, RARSLG-014-9.10 were evaluated from March 02-August 07, 2022. The experiment was laid out in a Randomized complete block design with three replications. The crop geometry was maintained at 50 cm × 28.5 cm in a four-meter square plot containing twenty-eight corms per plot. The genotype RARSLG-014-3.11 was found earliest on days to 50% sprouting, spike initiation, and floret opening. The genotype RARSLG-014-6.12 was noted to have maximum number of florets per spike and number of spikes per hill, longest rachis length, and a maximum number of cormels. Similarly, the genotype RARSLG-014-1.11 was a promising genotype in having a maximum number of corms. The longest length of the spike (140.66 cm) was found for genotype RARSLG-014-6.8.

Effect of spacing and boron application and spacing on growth, yield parameters and yield of sunflower (Helianthus annuus L.) hybrids in spring season

A field experiment was conducted during 2020 and 2021 spring season on loamy sand soils to study the effect of boron on sunflower hybrids sown under varied crop geometry. Treatment comprised four hybrids (PSH 1962, PSH 2080, KBSH 44 and KBSH 53) allocated to main plots, three spacings to sub plots (60 cm x 30 cm, 67.5 cm x 25 cm and 67.5 cm x 30 cm) and foliar application of boron (control and 220 ppm) at ray floret opening stage to sub sub plots which were replicated thrice. Hybrid KBSH attained the highest plant height and head diameter. Hybrids PSH 2080 and PSH 1962 produced similar but significantly higher seed yield, oil content and oil yield by virtue of higher number of seeds per plant (except over KBSH 53), seed weight per captulum, 100 seed weight and hectolitre weight than KBSH 44 and KBSH 53 in both years and mean analysis. Spacing of 60.0 cm x 30.0 cm and 67.5 cm x 25.0 cm resulted in similar but higher seed and oil yields than 67.5 cm x 30.0 cm. Foliar application ofboron significantly increased the seed yield, oil content and oil yield through improvement in growth and yield parameters over without it application.

Effect of edible dyes on value addition and post-harvest life of tuberose spikes

Tuberose is one of the most imperative bulbous crops with white fragrant florets, used for loose as well as cut flowers. All the commercial varieties have white colour flower only which is limiting factor in its popularity and marketing. By using edible dyes this issue may be solved for getting higher price in market as well as consumers satisfaction. An investigation was carried out to study the effect of food dyes on value addition and post harvest life of cut spikes of tuberose cv. Local Double in completely randomized design with factorial concept consisting thirty-six treatment combinations and one absolute control. Different treatments of food dyes and immersion time considerably induced colour in tuberose spikes without affecting postharvest life. The results revealed that 4% lemon yellow food dye with one hour immersion of tuberose cut spikes was found best in improving vase life (6.02 days), floret diameter (3.29 cm), opening of florets (49.66%) and visual appearance with minimum physiological loss in weight (16.91 % and 34.04 % at second and fourth day, respectively). Tinted tuberose cut spikes aids higher net return than white flowers, which will benefit farmers in fetching good prices.

The Extension of Vase Life in Cut Gerbera Flowers through Pretreatment with Gibberellin A3 in Combination with Calcium Chloride

The effect of pretreatment with gibberellin A3 (GA3) and calcium chloride (CaCl2) on the vase life of cut gerbera ‘Minou’ was investigated. Cut gerbera flowers were treated with GA3 and/or CaCl2 for 24 h and then transferred to an antimicrobial solution. Pretreatment with GA3 at 0, 29, 72, 144, and 289 µM delayed the opening of the tubular florets and promoted stem bending due to elongation of the flower stems, which shortened vase life. When cut gerbera was pretreated with 144 µM GA3 in combination with CaCl2 at 90, 180, 270, and 360 mM, stem elongation was suppressed with the increasing concentration of CaCl2. Next, the effect of pretreatment with 144 µM GA3, 270 mM CaCl2, and their combination on the vase life of the cut gerbera was investigated. Combined treatment with GA3 and CaCl2 significantly extended vase life more than GA3 alone and CaCl2 alone. The vase life of the cut gerbera ‘Banana’, ‘Kimsey’, ‘Pinta’, ‘Tim’, and ‘Vivid’ was significantly extended by pretreatment with 144 µM GA3 and 270 mM CaCl2. It was concluded that combined treatment with GA3 and CaCl2 was effective in extending the vase life of the cut gerbera.

Response of Gibberellic Acid and Corm Division on Floral Attributes of Gladiolus

This study was conducted to assess the response of Gibberellic acid and corm division on floral attributes of gladiolus cv. Punjab Dawn at Horticulture Research Farm of Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India during two consecutive year (2017-2019). The treatments comprised of growth regulators with two concentration i.e. GA3 100 ppm and 200 ppm including control (distilled water) and corms which are cut having 1bud, 2 buds and 3 buds and whole corm having 4 buds, 5 buds and 6 buds. The experiment was laid out in Randomized Block Design and three replications. The flowering characteristics of Gladiolus are mainly affected by higher concentration of GA3 (200 ppm) as well as whole corm under natural climatic condition. Regarding flowering parameters, it was found that GA3 200 ppm and whole corm i.e. 4 bud, 5 bud and 6 bud influence the quality and quantity parameters, viz. days to spike emergence, days to colour show, days to opening of florets, days to open florets without withering of basal floret, number of florets per spike, longevity of spike, length of spike and rachis (cm) and diameter of florets (cm) as compared to other treatments of GA3 100 ppm and control (distilled water) and cut corms which have 1 bud, 2 buds and 3 buds.

Effect of Varying Levels of pH and Edible Dyes on Tinting and Vase Life of Tuberose

Aims: The objective of this study is to explore how manipulating pH levels and incorporating edible dyes can extend the vase life, enhance the tinting, and improve the overall quality of tuberose flowers (Polianthes tuberosa).
 Study Design: The experiment was designed as a complete randomized design with three replications and a total of twenty-eight treatments.
 Place and Duration of Study: The experiment was conducted at the Horticulture lab in Department of Horticulture, School of Agriculture, Lovely Professional University, Phagwara, Punjab. The study was carried out over a specific duration in 2022.
 Methodology: Tuberose (Polianthes tuberosa) flowers were obtained from a local supplier. The flowers were carefully selected based on their uniformity in size and maturity. The study followed a completely randomized design (CRD) with 28 combinations of treatments. The pH levels included three treatments (pH 4, pH 5, and pH 6), while the edible dyes consisted of three treatments (Apple green, Lemon yellow, and orange red) at varying concentrations (1%, 2.5%, and 4%).
 Results: This research reveals that the best conditions for attaining the desired tinting effect on tuberose flowers are a slightly acidic pH level (pH 5) and a moderate concentration of lemon-yellow color (2.5%). This treatment combination was suitable for increasing the water uptake, floret opening, percent increase in floret opening and vase life. While the concentration of the dye influences the strength of the coloration, the pH level has a significant impact on how the color solution is taken up and absorbed by the flowers.
 Conclusion: The results of this study demonstrate that maintaining a pH level of 5 and using a moderate concentration (2.5%) of lemon-yellow color positively impacted both the tinting process and the longevity of cut tuberose flowers in vases.

Influence of Vermicompost and Bio-fertilizers on Growth and Flowering of Tuberose (Polianthes tuberosa L.) cv. Prajwal

The experiment was planned to sustainably improve the growth and yield of tuberose using bio-fertilizers and organic manures. performed in pots in completely randomized design (CRD) with 11 treatments having four replications to study the response of organic manures, chemical fertilizers and bio fertilizers on growth and flower yield of tuberose (Polianthes tuberosa L.) cv. Prajwal. The treatment containing sand + vermicompost (4:1) + Bio-fertilizers (Azotobacter&Pseudomonas sp.) was significantly superior in terms of plant height (70.50 cm), length of leaf (36.98 cm), Number of leaf (25.67), spike length (66.58 cm), rachis length (27.23 cm), diameter of stem (1.096 cm), florets number per spike (35), number of opened florets per spike (33.67), spikes number per clump, spike weight (75.33 g), bulb number per clump (21), bulb diameter (1.20 cm), bulb weight (3.98 g). While lowest values of these parameters were observed in the control (sand). Minimum days taken to bulb sprouting (21.75 days), days taken to complete bulb sprouting (24.50 days), days taken to spike emergence (93 days) and days taken to opening of first floret (106.75 days) were observed in sand + inorganic manures. Treatment having Sand + vermicompost (4:1) + Bio-fertilizers (Azotobacter&Pseudomonas sp. was observed best to promote growth and flowering of tuberose.

Prolonging Vase Life of Gladiolus (Gladiolus grandiflorus L.) var. Arka Amar with Various Preservative Solutions

Background: Arka Amar is a most popular variety of gladiolus which is used as cut flower and cut flowers are highly perishable materials and pregnable to large post-harvest losses. There is an immense post-harvest losses in value of cut flowers which is seen all along the marketing channels and it can be up to 40-50%. So, an experiment was carried out to find out the best combination of preservative solutions to enhance the vase life of Gladiolus (Gladiolus grandiflorus L.) var. Arka Amar. Methods: In this laboratory study during March 2022 to April 2022, different preservative solutions were analyzed to find out the maximum longevity of spikes. The experiment was laid out in C.R.D. with nine different combinations of sucrose, Al2 (SO4)3, AgNO3 and citric acid including control (distilled water). Result: The study revealed that the treatment T9 (Sucrose 2% + AgNO3 50ppm + citric acid 100 ppm) increased the percentage of water uptake both in weight and volume basis, minimize the days taken for opening of 1st floret (4.83 days), increase the length (7.41 cm) and diameter (13 cm) of floret, increase the percentage of opening of florets/spike (96.92%), maximize the longevity of floret (22 days) and flowering duration of spike (14.66 days). Visual scoring on appearance (8.71) and freshness (8.93) were also found significant for the above treatment combination.

Effect of Micronutrients on Growth and Flowering of Gladiolus (Gladiolus grandiflorus L.) under Subtropics of Jammu

An open field experiment was conducted during 2019-20 at the Experimental Farm, Division of Vegetable Science & Floriculture, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu, to evaluate the effect of micronutrients on growth, flowering and yield of gladiolus (Gladiolus grandiflorus L.) cv. ‘Nova Lux’. The experiment was laid out in Randomized Block Design with three replications and nineteen treatments. The different micro-nutrient like Fe, Zn and Mn was taken in different concentrations along with control. The results revealed that maximum plant height (97.74 cm), number of leaves per plant (9.04), leaf length (74.36 cm) and leaf area index (4.14) was recorded with the application of ZnSO4 at 0.2 % and FeSO4 at 0.2 %. Further, among the flowering traits, minimum duration for days taken for 1st floret opening, the maximum spike length (81.86 cm), rachis length (56.76 cm), number of florets per spike 917.69) and weight of the spike (74.78 g) was recorded with the application of ZnSO4 at 0.2 % and FeSO4 at 0.2 %. Thus, foliar application of micronutrients i,e. ZnSO4 at 0.2 % and FeSO4 at 0.2 % proved to be most effective in increasing the growth, flowering and corm production in gladiolus.

Multi-Year QTL Mapping and RNA-seq Reveal Candidate Genes for Early Floret-Opening Time in Japonica Rice

Floret-opening time (FOT) refers to the time between florets opening and closing within a day, and is a crucial agricultural trait for reproductive development, thermal tolerance and hybrid breeding in rice. However, little is known about the genetic basis and genes controlling FOT in rice. Here, we report the genetic mapping and transcriptome analysis of FOT in the japonica rice cultivar G23. Combining the QTLseqr and GradedPool-seq (GPS) methods, we located a major quantitative trait locus (QTL), qFOT6, on chromosome 6 in multiple years and under different environments. Integrating RNA-seq analysis, we selected 13 potential candidate genes in the qFOT6 interval that might be associated with FOT in G23. Taken together, our work uncovers a major QTL and potential candidate genes for FOT in rice, thus providing invaluable clues for rice breeding.

Effect of boron on growth and flowering in gladiolus (Gladiolus sp.) cv. Malaviya Shatabdi

A field trial was conducted to find out the optimum dose of Boron in maximizing growth and improving flowering attributes in gladiolus (Gladiolus sp.) cv. Malaviya Shatabdi at Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh during 2020-21. The treatments were given as: the control (distilled water), 0.1% boron, 0.2% boron, 0.3% boron, 0.4% boron, 0.5% boron, 0.6% boron, 0.7% boron, 0.8% boron, 0.9% boron and 1.0% boron, applied at 60 and 75 days after planting. There was maximum number of leaves/plant (13.94), maximum width of scape (2.67 cm) was noted at 0.3% of B, maximum plant height was recorded with foliar application of 0.5% B (70.42 cm), whereas leaf length (65.50 cm) and leaf width (2.63 cm) were maximum at 0.6% of B as compared to other treatments. The earliest spike emergence and colour were noted in 68.44 days and 77.88 days respectively at 0.2% of B spray. Earliest opening of first and fifth florets was seen with 0.6% of B (85.06 and 90.00 days respectively). Maximum length (9.72 cm) and diameter (7.81cm) of first floret was observed in 0.2 % and 0.3% B treatments, whereas, maximum length (8.62 cm) and diameter (7.40 cm) of fifth floret was detected in 0.6% and 0.5% B treatments respectively. Results also showed that application of B significantly reduced flowering duration among all the treatments as compared to the control.