Giberellic Acid Research Articles

Germination Indices and Seedling Growth Parameters in Maize under Salinity Stress with Varying Concentrations of Giberellic Acid (GA)

Salinity stress is one of the factors limiting seed emergence and seedling development in sunflower at New halfa scheme in East of Sudan. A study of two factors pots experiment was conducted during winter season of 2019 to evaluate germination indices and seedling growth characters of maize seeds under salinity stress with varying concentrations of synthetic growth regulator namely (GA3). The experiment was laid out according RCBD with three replications. Treatments consisted of five levels of salinity (0, 0.5, 1.0, 1.5 and 2% ) designated as Na0, Na0.5, Na1.0 ,Na1.5 and Na2.0, and four levels of GA3 were (0, 50,75 and 100 p.pm) designated as G0, G50, G75 and G100, respectively,. The studied parameters include germination indices; daily germination (MDG), daily germination speed (DGS), final germination percentage (FGP), mean emergence time (MET), mean Energy of germination (EE), emergence index (EI), coefficient of uniformity of emergence (CUE) and vigour index (SVI). Also, seedling fresh and dry weight, shoot length and root length were measured, and the shoot/root ratio was calculated. The negative effects of salinity stress significantly decreased germination indices and seedlings growth characters in a dose dependent manner. The results showed that, application of GA3 at medium levels concentration (specify those doses) increased all studied parameters. In conclusion, application of high Ga3 levels enhanced all germination indices and seedlings growth characters while high salinity levels reduced these traits of maize seeds. Such result has made the base for further study that should be conducted in different seasons with different growth regulators involving different parameters of other crops.

Impact of Plant Growth Regulators on Seed Health during Accelerated Ageing Test in Chickpea [Cicer arietinum (L.)] Seeds

Background: Research was conducted to ascertain the impact of hormonal seed strengthening on seed health status under an accelerated ageing test in chickpea (Cicer arietinum L) at the state seed testing laboratory during the Rabi seasons of 2018-19 and 2019-20. Four replications of the Blotter test were performed CRD plan. As per continuous evaluation and observation, under accelerated ageing increased pathogens were observed with increased temperature and RH, the seeds treated with salicylic acid resulted with least pathogen infection while compared to other treatments. Methods: The current experiment was conducted in the state seed testing laboratory, Department of Genetics and Plant Breeding, SHUATS, Prayagraj, Uttar Pradesh, between the years of 2018 and 2020. 37 distinct treatment combinations were employed in the experiment. The seeds were placed in an accelerated ageing condition with high temperature and relative humidity. Hormonal seed strengthening is the activity of infusing PGRs into old seeds to make them fresh again with the help of PGRs (salicylic and giberellic acid) treatments into old seeds and increase the vigour index of seeds. Result: In this experiment chick pea seeds treated with combination of gibberellic acid and salicylic acid resulted in least infection of seed pathogens we can recommend these for maintaining seed health status.

Genomic Insights into Seed Germination Differences in Buffalobur (Solanum rostratum Dunal) under Contrasting GA and ABA Availability

Buffalobur (Solanum rostratum Dunal) is an invasive species that seriously endangers crop production and the ecological environment. Seeds are the primary source of infestation; therefore, understanding the molecular basis of buffalobur seed dormancy, and germination is crucial for precision weed management. In this study, high-throughput RNA-Seq was performed on buffalobur seeds, which imbibed under 0.35 mmol/L giberellic acid (GA) and 0.35 mmol/L abscisic acid (ABA). In total, 3658 differentially expressed genes (DEGs) were identified during seed germination. Gene annotation revealed that the DEGs were significantly enriched during the protein metabolic process, as well as the macromolecular complex and cytoplasmic part for ABA versus GA. Pathway analysis predicted that the DEGs were associated with metabolic pathways, the biosynthesis of secondary metabolites and ribosome. Nine germination-related genes involved in the biosynthesis and metabolism of the phytohormones and encoding of the endo-β-mannanase (EBM) were identified. Gene expression indicated that GA upregulated GA3OX1 and MAN2 expression to increase the EBM activity, which caused the endosperm cap to weaken and lowered the puncture force to trigger the germination of buffalobur. The obtained results would be helpful to clarify the regulation of seed dormancy and the germination of buffalobur, and could serve as a valuable resource when unravelling the genetic basis of seed biology of this weed species.

Benefit-cost analysis of the optimum level of giberellic acid as an inductor of the germination of chiltepín chili (Capsicuum annuum var. aviculare) cultivated in backyard

The gastronomic culture of Mexico is linked to various vegetables, to certain species and, in particular, chili. It is clear that chilies are plant species that have great importance in the identity of the people of Mexico. The objective of this research was to analyze the cost-benefit of sowing chiltepin-type chili in the backyard using the optimal level of applying gibberellic acid as a germination inducer. Prior to the cost-benefit analysis, seven treatments were evaluated to select the best one to induce chiltepín germination. The treatments were supported by the application of gibberellic acid in different percentages, plus a control (T1-no application). The results showed that the optimal level of germination was obtained with the application of substrate, perlite, vermiculite and 5% gibberellic acid. With this treatment, a greater number of plants and 95% rooting were obtained, compared to the control treatment (T1) as well as a greater yield of chili (171 g plant-1) compared to the control (128 g plant-1). A cost-benefit ratio of 1.33 was calculated for the best biological treatment, so it is concluded that it is possible to improve family income through the production of chiltepin-type chili under backyard conditions.

Molecular Symmetry of Permethylated β-Cyclodextrins upon Complexation

The Cn molecular symmetry implicated by the schemes with which cyclodextrins (CDs), the well-known cyclic oligosaccharides, are introduced in the literature, is not valid. Numerous studies have shown that CDs are rather flexible with their macrocycle adopting various conformations that enable the inclusion complexation of guest molecules of various shapes. In this work, the loss and gain of the C7 symmetry of the heptakis (2, 3, 6-tri-O-methyl)-β-CD (TM-β-CD) is investigated by means of its conformation geometrical features in its hydrated form and upon complexation with molecules of different shapes. For this, the crystal structure of the inclusion complex of a bulky guest molecule (giberellic acid) in TM-β-CD is presented for the first time and compared with the previously determined crystal structures of monohydrated TM-β-CD and the inclusion complex of a linear monoterpenoid (geraniol) in TM-β-CD. The structural investigation was complemented by molecular dynamics simulations in an explicit solvent, based on the crystallographically determined models. The crucial role of the guest, in the symmetry gain of the host, reveals a pronounced induced-fit complexation mechanism for permethylated CDs.

Effect of Plant Growth Regulators Giberellic acid (GA3) And Salicylic Acid (SA) on Growth and Yield of Carnation (Dianthus caryophyllus) under Naturally Ventilated Polyhouse

The present investigation entitled “Effect of plant growth regulators Gibberellic Acid (GA3) and Salicylic Acid (SA) on the growth and yield of carnation under naturally ventilated polyhouse”, was carried out during November, 2021 to April 2022 in, Naturally Ventilated Polyhouse, Department of Horticulture, Naini Agricultural Institute, SHUATS, it was concluded that the plant growth regulators treatments rendered their significant effect on almost all the growth, flowering and yield characters as well as quality of carnation. The treatment T3 i.e. application of GA3 @ 200 ppm was found superior in terms of Plant height (102.27cm), number of leaves (203.67), number of shoots (7.67), internodal length (7.73cm), number of internodes per shoot (17), bud length (10cm), bud diameter (2.87cm), flower diameter (6.80cm), flower length (5.67cm), flower stalk length (96.93cm), vase life (10.33), number of cut flower stalks per plant (7.00) and number of cut flower stalks per square meter (175). However, plants treated with SA @ 120ppm took minimum days for bud initiation (112.67 days) and the days taken to bud opening (24.67). Among the different treatments the highest Gross return (Rs/200m2) (7,00,000), Net return (441565), benefit cost ratio (2.70) was obtainedunder the use of GA3 @ 200 ppm (T3).

Light intensity and giberelic acid in the seedling\production of four ornamental species

Ornamental species, especially those involving the use of seedlings in trays to serve residential gardens, need to be produced quickly for commercialization, which requires studies that provide such a condition. The present work aimed to evaluate the effect of light intensity and exogenous application of gibberellin on seedlings of four ornamental species (Calendula officinalis, Gypsophila elegans, Solenostemon scutellarioides and Viola wittrockiana). The experiment was carried out at the Universidade Tecnológica Federal do Paraná, Campus Dois Vizinhos. The seeds were sown in trays containing substrate composed of a mixture of humic Distroferric Red Latosol: medium texture sand: commercial substrate, in the volumetric proportion of 2:1:1, respectively. The trays were kept in shading environments, using black screens with 35%, 50% and 80% shading intensity, red with 35% shading, in addition to full sun. After 30 days of emergence, gibberellic acid solution was applied to the seedlings at concentrations of 0 mg L-1 and 300 mg L-1. Emergence, emergence speed index, mean emergence time, total length, shoot and roots, number of leaves, leaf area, root volume density, shoot, root and total dry matter were evaluated. For each environmental condition of cultivation, the values of temperature and air humidity and light intensity were obtained. The use of gibberellic acid proved to be beneficial for Viola wittrockiana and Solenostemon scutellarioides. The shading environments, regardless of color and light intensity, were more favorable for the formation of seedlings of these four ornamental species.

Synergistic Modulation of Seed Metabolites and Enzymatic Antioxidants Tweaks Moisture Stress Tolerance in Non-Cultivated Traditional Rice Genotypes during Germination.

Traditional rice landraces are treasures for novel genes to develop climate-resilient cultivars. Seed viability and germination determine rice productivity under moisture stress. The present study evaluated 100 rice genotypes, including 85 traditional landraces and 15 improved cultivars from various agro-ecological zones of Tamil Nadu, along with moisture-stress-susceptible (IR 64) and moisture-stress-tolerant (IR 64 Drt1) checks. The landraces were screened over a range of osmotic potentials, namely (−) 1.0 MPa, (−) 1.25 MPa and (−) 1.5 MPa, for a period of 5 days in PEG-induced moisture stress. Physio-morphological traits, such as rate of germination, root and shoot length, vigor index, R/S ratio and relative water content (RWC), were assessed during early moisture stress at the maximum OP of (−) 1.5 MPa. The seed macromolecules, phytohormones (giberellic acid, auxin (IAA), cytokinin and abscisic acid), osmolytes and enzymatic antioxidants (catalase and superoxide dismutase) varied significantly between moisture stress and control treatments. The genotype Kuliyadichan registered more IAA and giberellic acid (44% and 35%, respectively, over moisture-stress-tolerant check (IR 64 Drt1), whereas all the landraces showed an elevated catalase activity, thus indicating that the tolerant landraces effectively eliminate oxidative damages. High-performance liquid chromatography analysis showed a reduction in cytokinin and an increase in ABA level under induced moisture stress. Hence, the inherent moisture-stress tolerance of six traditional landraces, such as Kuliyadichan, Rajalakshmi, Sahbhagi Dhan, Nootripathu, Chandaikar and Mallikar, was associated with metabolic responses, such as activation of hydrolytic enzymes, hormonal crosstalk, ROS signaling and antioxidant enzymes (especially catalase), when compared to the susceptible check, IR 64. Hence, these traditional rice landraces can serve as potential donors for introgression or pyramiding moisture-stress-tolerance traits toward developing climate-resilient rice cultivars.

Slight Changes in Fruit Firmness at Harvest Determine the Storage Potential of the ‘Rojo Brillante’ Persimmon Treated with Gibberellic Acid

Today, the ‘Rojo Brillante’ persimmons undergoing prolonged storage are treated with giberellic acid, which allows the delay of the harvesting to November-December. Although during this period the fruit maintained high commercial firmness, practical experience indicates very different behavior during the posterior cold storage, depending on the harvest moment. To explain what leads to these differences, an in-depth study of the physicochemical and microstructural changes occurring in the fruit during five commercial harvest times from November to December was carried out. During this period, slight variations in firmness occurred, ranging from 48 to 40 N. Nevertheless, the fruit behavior under cold storage was strongly influenced by the harvest date, which was explained by the degradation of cell wall, cell membrane and tonoplast, mainly noted in fruit from the latest harvests. Therefore, the fruit harvested with firmness close to 48 N had a highly structured cell, which maintained firmness during cold storage for up to 90 days. The fruit harvested with 43 N presented a more degraded structure, while the fruit with initial firmness around 40 N underwent major ultrastructure cell wall and membranes modifications, which led to greater firmness loss. Therefore, the fruit firmness at harvest is decisive for its storage potential.

Somatic embryogenesis mediated micropropagation of polyembryonic cultivars of mango Vellaikolumban and Olour using nucellus tissue

Abstract Somatic embryogenesis mediated micropropagation from nucellus tissue was attempted in polyembryonic mango at the ICAR-Indian Institute of Horticultural Research, Bengaluru during 2016–2019. Studies were conducted to optimize the different stages of somatic embryogenesis namely induction, proliferation, conversion, maturation, germination of somatic embryos and ex vitro establishment of plantlets using nucellus tissue. For culture initiation, various developmental stages of fruits ranging from less than 20 days post-pollination to more than 60 days-post pollination of cultivars Vellaikolumban and Olour were utilized. Fruits of 30–40 days post-pollination in Vellaikolumban and 40–50 days post-pollination in Olour gave better percentage callusing with fewer days for callus initiation and callus formation. Embryonic calli developed on induction medium containing Rugini olive (RO) constituents, 6% sucrose, and 5 ppm each of 2, 4-Dichlorophenoxyacetic acid (2, 4-D) and Giberellic acid (GA3). Upon shifting to proliferation medium (RO with 6% sucrose, 5 ppm each of 2, 4-D and GA3, 400 mgL−1of glutamine and 20% v/v coconut water) pro-globular and globular embryos were formed within 4–5 weeks. Further development of somatic embryos through early heart, late heart and cotyledonary stages occurred in conversion medium (half strength B5 salts, full RO organics, 5 ppm of Indole-3-Acetic Acid (IAA), 20% coconut water and 200 mgL−1 of casein hydrolysate). Maturation of embryos was obtained by using 0.01 mg L−1of Abscisic acid (ABA) and 100 mg L−1of Polyethylene glycol (PEG). Germination of embryos with shoot and root initiation was observed in the presence of 5 ppm of zeatin. Our results show that somatic embryogenesis can be used as an alternative method to conventional propagation methods for rapid multiplication of uniform planting material in polyembryonic mango cultivars.

Response of morphological and biochemical traits and transcriptomic of CDPKs and P5CS Genes to phytohormones and nutrients in two bread wheat germplasms under salinity conditions

Several enzymes play an important role in the biosynthesis of osmolyte in plants. The main objective of this work is to study the effects of salt stress, kinetin+potassium and giberellic acid+potassium on calcium-dependent protein kinases (CDPKs) and delta-1-pyrroline-5- carboxylate synthase (P5CS) genes expression of two bread wheat varieties. The results shodwe that, salts stress reduced the plant growth of the two wheat germplasms. Moreover, the addition of kinetin+ potassium improved the performance of morphometric parameters while the addition of giberellic acid +potassium has less effect. On the biochemical level, results indicated that salt stress increased the proline contents compared with control plants. Extra increase in proline contents was recorded by kinetin+ potassium, while the treatment of giberellic acid +potassium showed almost similar results as in salt stress only. On the molecular level, salt stress, kinetin and giberellic acid significantly increased the two genes expression of CDPKs and P5CS with more effect in presence of kinetin+ potassium.

​​The Effects of Gibberellic Acid (GA3) Applications on the Physiological Features of Groundnut (Arachis hypogaea L.) under Different Salt (NaCI) Stress Conditions

Background: Salinity is one of the most imperative problems of farmers worldwide. Reports are available that the external application of GA3 can reduce harmful effects of salinity. Low concentration and small quantities of GA3, a phytohormone, is essential to hasten the growth and development of plants. The current study was aimed to test the efficiency of GA3 on the impart of salt tolerance in terms of better nutrient uptake under salt stress situation and to determine the effect of external giberellic acid applications on the physiological properties and proline level of peanuts under different salt (NaCl) stress conditions on the degree of resistance to salt stress in peanuts. Methods: Trial was established as split plot design with 3 replications and NC-7 variety was used as a material. The chlorophyll content in leaves, ion (K, Na, Mg, Ca) content, cell membrane permeability were searched in the research. To determine the physiological responses of groundnut in the conditions of Gibberellic asid (GA3), (0, 5, 15 mM) applications under the different salt (Nacl), (0, 25, 50, 100 mM) stress conditions at the Plant Growth Room in the GAP Agricultural Research Institute in Şanlıurfa, Turkey in 2019. The chlorophyll content in leaves, ion (K, Na, Mg, Ca) content, cell membrane permeability were searched in the research. Result: The increasing salt applications decreases the leaf chlorophyll content and leaf ions (K, Mg, Ca) content, in contrast, increased the cell membrane permeability, proline content and sodium concentration were determined. The gibberallic asid applied externally against salt stress were determined to have the positive effects on traits; leaf chlorophyll content, ion (K, Na, Mg, Ca) content, cell membrane permeability, proline content.

THE EFFECT of GA3 AND SALINITY on GROWTH of ROSELLE (Hibiscus sabdariffa L.)

In order to alleviate the deleterious effects of salinity, different types of phytohormones have been used. Among them, GA3 has been the main focus of some plant scientists. This study aimed to evaluate the effect of gibberellic acid and salinity on growth and production of roselle (Hibiscus sabdariffa L). This research was conducted in a greenhouse of Agriculture Faculty, University of Sumatera Utara, Medan. The study used utterly randomized design with two factors. The first factor was gibberellic acids. They were gibberellic acid (5 mg L-1) and no gibberellic acid. The second factor was salinity. They were 0 dsm-1 and 4-5 dsm-1. The interaction between gibberellic acid and salinity acid indicated a significant effect on the percentage of germination, chlorophyll a and b and beta-carotene. The application of giberellic acid helped in the tolerance of plants to salinity. Thus, application of GA3 become essential to improve overall productivity in salinity.

EFFECT OF PHITOREGULATOR DOSES ON GERMINATION AND VEGETATIVE PHASE OF SOYBEAN WITH LOW PHYSIOLOGICAL QUALITY SEEDS

The objective of this work was to evaluate seed germination and the initial development of soybean plants with low physiological quality seeds submitted to different doses of phytoregulator. The experiment was carried out from March to April 2018 in Campo Novo do Parecis, MT, Brazil. The experimental design was of completely randomized blocks, in a 3x4 factorial scheme, being three soybean cultivars: Monsoy 7739, Desafio and Monsoy 8372, and four doses of phytoregulator: 0.0; 0.5; 0.75 and 1.0 L ha-1 of Stimulate® composed of cytokinin, indole butyl acid and giberelic acid. Totaling 12 treatments with four replicates. The evaluated variables were: initial germination, final germination, plant height, dry shoot mass, dry root mass and total dry mass. The cultivars responded differently to the phytoregulator doses. The cultivar Monsoy 7739 responded positively to the use of phytoregulator, as it increased germination, presented higher plant height, dry root mass and total dry mass, at the maximum dose of 1.0 L ha-1.The cultivar Desafio responded negatively to the phytoregulator, as germination presented significant differences compared the other evaluated variables. Monsoy 8372 did not conclusively respond to the use of the phytoregulator conclusively.

Identification, characterization, and expression profiles of the GASA genes in cotton

BackgroundGASA (Giberellic Acid Stimulated in Arabidopsis) gene family plays a crucial role in the phytohormone signaling pathway, growth and development, and stress responses in plants. Many GASA homologs have been identified in various plants. Nevertheless, little is known about these proteins in cotton.ResultsIn the current study, we identified 19, 17, 25, 33, and 38 GASA genes via genome-wide analyses of Gossypium herbaceum, G. arboreum, G. raimondii, G. barbadense, and G. hirsutum, respectively, and performed comprehensive bioinformatics and expression analyses. According to our results, 132 GASA proteins shared similar protein structures and were classified into four groups based on the phylogenetic tree. A synteny analysis suggested that segmental duplication was a key driver in the expansion of the GASA gene family. Meanwhile, the cis-element and protein interaction analyses indicated that GhGASA proteins play a significant role in the hormone responses. Transcriptomic and qRT-PCR (Quantitative real time-polymerase chain reaction) analyses revealed diverse expression profiles of the GhGASA genes in different organs under abiotic stresses, indicating that some GhGASA genes possibly participate in fiber development and abiotic-stress responses.ConclusionsThe GASA genes in cotton were systematically identified and analyzed for the first time in this paper, and it suggested that the GASA genes are important to the development and growth of cotton. These results will support future exploration of the functions of GASA genes in cotton.

Antimicrobial peptides in the seedling transcriptome of the tree legume Peltophorum dubium

Antimicrobial peptides (AMPs) play an essential role in plant defense against invading pathogens. Due to their biological properties, these molecules have been considered useful for drug development, as novel agents in disease therapeutics, applicable to both agriculture and medicine. New technologies of massive sequencing open opportunities to discover novel AMP encoding genes in wild plant species. This work aimed to identify cysteine-rich AMPs from Peltophorum dubium, a legume tree from South America. We performed whole-transcriptome sequencing of P. dubium seedlings followed by de novo transcriptome assembly, uncovering 78 AMP transcripts classified into five families: hevein-like, lipid-transfer proteins (LTPs), alpha hairpinins, defensins, and snakin/GASA (Giberellic Acid Stimulated in Arabidopsis) peptides. No transcripts with similarity to cyclotide or thionin genes were identified. Genomic DNA analysis by PCR confirmed the presence of 18 genes encoding six putative defensins and 12 snakin/GASA peptides and allowed the characterization of their exon-intron structure. The present work demonstrates that AMP prediction from a wild species is possible using RNA sequencing and de novo transcriptome assembly, regarding a starting point for studies focused on AMP gene evolution and expression. Moreover, this study allowed the detection of strong AMP candidates for drug development and novel biotechnological products.

Aplicação adicional de bioestimulantes em estádio reprodutivo de feijão comum (Phaseolus vulgaris l.) com intuito de acréscimo na produtividade

The present work had as objective to evaluate the productive response of the bean due to the additional spraying of biostimulants. a randomized complete block design with 6 treatments and 5 replications. Three products were used to compose the treatments: 1 - 4-Indol-3-ylbutyric Acid (0.05 g/L), Kinetin (0.09 g/L) and Giberelic Acid (0.05 g/L); 2 - Giberelic acid (400 g/kg); 3 - Gibberellic acid (18.8 g/L) and Benzyladenine (18.8 g/L). The evaluated variables consisted of plant height, stem diameter, number of nodes per plant, number of pods per plant, number of grains per pod, mass of one thousand grains and productivity. The Scott-Knott 5% probability was performed. There was no statistically significant difference for the variables, except for productivity, in which the best treatments were 4, 5 and 6. Therefore, among these treatments the best one due to the cost-benefit was the T4.

Use of bioreactors for large-scale multiplication of sugarcane (Saccharum spp.), energy cane (Saccharum spp.), and related species

The objective of this study was to set up a plant micropropagation facility to mass propagate sugarcane, energy cane, and related clonally propagated species. An efficient methodology for micropropagation of energy cane and perennial grasses using temporary immersion bioreactors was developed. Several different methods of tissue culture initiation, multiplication, and rooting were evaluated for several varieties of sugarcane (Saccharum officinarum L.) and sugarcane-related species such as Erianthus spp., Miscanthus spp., and Sorghum spp. × sugarcane hybrids, all from a germplasm collection. Apical meristem cultures were initiated for all genotypes that were micropropagated, when liquid or semisolid Murashige and Skoog (MS) medium was used, which was supplemented with 0.1–0.2 mg L−1 BAP, 0.1 mg L−1 kinetin, 0–0.1 mg L−1 NAA, and 0–0.2 μg L−1 giberellic acid. These cultures produced shoots between 4 and 8 wk after initiation. Shoot regeneration from leaf rolls or immature inflorescences was observed as early as 4 wk after initiation. Shoot multiplication was successful for all genotypes cultured in MS medium with 0.2 mg L−1 BAP and 0.1 mg L−1 kinetin. Energy cane had a significantly higher combined multiplication rate when grown under four or five LED lamps than when grown under three LED lamps, or under fluorescent lights in a growth chamber. The addition of 2 mg L−1 NAA produced faster and better rooting in all of the genotypes tested. Shoots produced well-developed roots after one cycle of 15–21 d in the bioreactors. The maximum number of plantlets produced per bioreactor was 1080. Plantlets developed a vigorous root system and were ready to be transplanted into the field after 2 mo. A protocol was standardized for different energy cane clones that were recommended for their biomass production and cell wall composition. Different tissues were used to speed up or facilitate tissue culture initiation. Visual assessment of micropropagated plants in the field did not show any off-types, based on gross morphological changes of plant morphology or disease reaction, compared to plants of the same genotype derived from a traditional propagation method (stem cuttings). This is the first report of energy cane and Miscanthus spp. micropropagation using the SETIS bioreactor.

Influence of different environmental conditions and giberellic acid treatment on flowering time of divergent genotypes of cabbage (Brassica oleracea var. capitata L.) and their F1 hybrids

In the process of cabbage breeding and seed production, one of the most important characteristics is the time of flowering. In order to investigate the influence of genotype, season and term of sowing on the flowering process, as well as the genetic control of this trait, an experiment was conducted with three genotypes of cabbage N, B and Scc of different geographical origin and different vegetation length, as well as three new F1 hybrids N x Scc , B x Scc and B x N obtained by hybridization between genotypes. The experiment was conducted during three temperature different seasons S1, S2 and S3 (average cold, cold and warm seasons), in three different sowing terms: August 15 (I), September 1 (II) and September 15 (III). During the winter period favorable for vernalization, two treatments with 300 ppm GA3 were performed. A statistically significant influence of all examined factors: genotype, year, sowing term and gibberellin GA3 treatment, on flowering time was determined. AMMI analysis determined the degree of adaptability of genotypes depending on the growing season, sowing terms and GA3 treatment for the trait time of flowering. The highest stability based on ASV values for flowering time was shown by hybrid BxN and its parental component genotypes B and N, while the hybrid Scc x B proved to be the most unstable in terms of flowering time. The pattern of relative expression of the most important flower repressor BoFLC2 gene showed a certain correlation with the flowering time of genotypes. The lowest quantitative expression of this gene was found in genotype B and it had the earliest flowering in all seasons, while genotype N had the highest relative expression of the BoFLC2 locus and the latest flowering.

Enhanced germination performance of dormant seeds of <i>Eragrostis tef</i> in the presence of light

Lack of germination or low germination due to seed dormancy prevents successful crop establishment in several important plants. To determine the presence of innate seed dormancy and effects of stress-related plant hormones on germination performance of Teff (Eragrostis tef) seeds, we primed seeds in 1% KNO3 for 24 hours in dark conditions at 21 ± 0.5 ºC along with varying concentrations of chemicals known to influence seed germination, including: acetyl salicylic acid (ASA); methyl jasmonate (JA-Me); giberellic acid (GA3); and indole acetic acid (IAA). Primed seeds were incubated either in constant light (210 µM/m2/s) or in darkness at 21 ± 0.5 ºC. The results indicated that primingsignificantly improved final germination percentage (FGP) in both light (92.5%) and dark (89.4%) conditions compared with untreated seeds. The inclusion of plant hormones in the priming media generally had limited effects, except for 10 mM ASA (94.5%) and 100 mM GA3 (92.5%). ASA generally provided faster seed germination than seeds primed in 1% KNO3 only, while the other plant hormones had no effect on the time required for 50% of FGP in the dark. Priming had no significant effect on time span of germination in either light or dark incubation conditions. The results demonstrate that E. tef has light-inducible seed germination and about half of freshly harvested seeds can be dormant, which can be eliminated to some extent by priming seeds in 1% KNO3.