Application Of Plant Growth Regulators Research Articles

Application of Plant Growth Regulators Mitigates Water Stress in Basil

Application of Plant Growth Regulators Mitigates Water Stress in Basil

Impact of Foliar Application of Plant Growth Regulators in Soybean [Glycine max (L.) Merill)] on Seed Quality and Seedling Establishment

Impact of Foliar Application of Plant Growth Regulators in Soybean [Glycine max (L.) Merill)] on Seed Quality and Seedling Establishment

Influence of plant growth regulators on fruit set, yield and quality of mango varieties under HDP

Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Phytohormones determine the formation of flowers, fruit set, stems, leaves, shedding of leaves, and development and ripening of fruits. They shape the plant, affecting seed growth, time of flowering, sex of flowers, senescence of leaves and fruits. Hormones are vital for plant growth and lacking them, plants would be mostly a mass of undifferentiated cells. Plant growth regulators include salicylic acid, CPPU, tricontanol and brassinosteroid. The production of poor quality fruits is a matter of common experience. It would be therefore worth while to improve the yield and quality of fruit crops by foliar application of plant growth regulators. The use of growth regulators has become an important component of agro-technical procedures for most of the cultivated plants and especially for fruit plants. In this review, we focus on the role of plant growth regulators on fruit production.

Plant Growth Regulators Enhance Maize (Zea mays L.) Yield under High Density by Optimizing Canopy Structure and Delaying Leaf Senescence

Shaping the canopy architecture and delaying leaf senescence in maize are pivotal strategies for extending the crop’s photosynthetic period and improving yield. The application of plant growth regulators (PGRs) is a critical cultivation measure, with the timing of application being of paramount importance. To explore the effects of PGR application time on maize canopy structure, leaf senescence characteristics and yield, a comparative two-year field study was undertaken during the 2019–2020 growing seasons at the Gongzhuling Experimental Station of the Jilin Academy of Agricultural Sciences, utilizing a PGR containing ethephon as the active ingredient. The experiment was structured with two plant densities of 60,000 and 90,000 plants ha−1, and three distinct PGR application protocols: T10 (application of PGR at the 10th leaf stage), T15 (application at the 15th leaf stage), and CK (control group sprayed with water). The result indicated that the yield increased by 5.62% following T15 treatment compared to the CK under high density (90,000 plants ha−1). Furthermore, the kernel per ear and the 1000-kernel weight increased by 3.93% and 5.62% respectively, while the abortion rate decreased. Correlation analysis showed that yield and yield components were correlated with plant morphology, physiology, and aging characteristics under 90,000 plants ha−1. Pollen density was also positively correlated with the top leaf area and the top leaf angle (p < 0.01). Furthermore, relative green leaf area at maturity (RGLAM) showed positive correlations with chlorophyll b, superoxide dismutase activity (SOD), peroxidase activity (POD), catalase activity (CAT), and soluble protein content (p < 0.01), while displaying a negative correlation with malondialdehyde content (MDA) (p < 0.01). Spraying plant growth regulators at the 15-leaf stage under high density can effectively enhance the top canopy structure of the maize and reduce the upper leaf area and angle, increase pollen density, and boost the number of grains. Furthermore, it delayed the senescence of leaves, prolonged the functional period of the leaves, increased kernel weight, optimized light resource utilization, and ultimately enhanced the maize yield.

Sustaining the Yield of Maize, Blackgram, Greengram, Groundnut, Cotton, Sugarcane, and Coconut through the Application of Nutrients and Plant Growth Regulator Mixture.

The foliar application of nutrients and plant growth regulators (PGRs) at critical crop growth periods can improve the yield of field crops. Hence, the present study was conducted to quantify the effects of the combined application of nutrients and PGRs (crop-specific formulation) on maize, blackgram, greengram, groundnut, cotton, sugarcane, and coconut yield. In all the crops except coconut, the treatments included (i) a foliar spray of crop-specific nutrients and PGR combinations and (ii) an unsprayed control. In coconut, the treatments included (i) the root feeding of coconut-specific nutrients and PGR combinations and (ii) an untreated control. Crop-specific nutrient and PGR formulations were sprayed, namely, Tamil Nadu Agricultural University (TNAU) maize maxim 1.5% at the tassel initiation and grain-filling stages of maize, TNAU pulse wonder 1.0% at the peak flowering stage of green gram and black gram, TNAU groundnut-rich 1.0% at the flowering and pod-filling stages of groundnut, TNAU cotton plus 1.25% at the flowering and boll development stages of cotton, and TNAU sugarcane booster 0.5% at 45 days after planting (DAP), 0.75% at 60 DAP, and 1.0% at 75 DAP of sugarcane. The results showed that the foliar application of TNAU maize maxim, TNAU pulse wonder, TNAU groundnut-rich, TNAU cotton plus and TNAU sugarcane booster and the root feeding of TNAU coconut tonic increased the yield of maize, pulses, groundnut, cotton, sugarcane, and coconut, resulting in higher economic returns.

Leader Bagging Improves Lateral Branching and Cropping Potential of ‘Gala’ and ‘WA 38’ Apple during Orchard Establishment

Inadequate lateral branch development can lead to decreased apple (Malus ×domestica Borkh.) orchard productivity and profitability in modern high-density orchard systems. Although plant growth regulator applications are used to increase lateral branching on leaders of young apple trees, inconsistent responses have been observed in the southeastern United States. In North Carolina and Washington, three experiments were conducted to identify effective leader management strategies to increase lateral branching. Effects and interactions of leader bagging, 6-benzyladenine (6-BA), and 6-BA + gibberellic acid (GA4+7) on lateral branch development of 1-year-old leaders were evaluated. Across all experiments, leader bagging was an influential factor. When compared with unbagged trees, leader bagging increased lateral branch number (20% to 48%), number of feathers (74% to 125%), average branch length (28% to 34%), and total linear bearing surface (428%) of the treated section of the leader. Blossom cluster density and final fruit set were increased in bagged trees, 65% and 36%, respectively. At the rates and timings tested, 6-BA and 6-BA + GA4+7 were generally ineffective in stimulating lateral branching and interactions among the factors evaluated were not influential. Leader bagging was an effective lateral branch induction strategy, although the mechanism of action is poorly understood. Future research to characterize the bagged environment and/or physiological responses to bagging may aid in the development of future environmentally sustainable technologies to stimulate lateral branching of apple trees.

Foliar application of Boron, Calcium, and Indole-3-butyric acid on onion plants to improve seed production

Onion is the third most important cultivated vegetable crop around the world. Two types of varieties are cultivated: Open pollinated cultivars (OP) and first generation hybrids (F1). Little is known about the effects of foliar applications on onion seed production. This study was conducted to evaluate the enhancement of onion seed yield and seed quality through foliar applications of Boron (B), Calcium (Ca), and an auxin, indole-3-butyric acid (IBA). Male-sterile lines (MSL), and OP planted in pots and open field conditions were used over four seasons. The experiments were carried out with different levels of nutrients and IBA applied to the plants. Our results showed that foliar applications of nutrients and plant growth regulators were effective methods to improve onion seed yield and the number of seed per fruit, while seed quality parameters remained stable. The seed yield was enhanced by B by up to 83 %, but with an increasingly wide variability in comparison to the control. Indole-3-butyric acid improved yields when it was applied alone and mixed with B and Ca (40–45 % for OP and MSL, respectively) compared to the control. Therefore, foliar application of IBA, B and Ca could be effective in improving onion seed yields.

Agrochemical Spray Technology Adoption and Safety Awareness Assessment in Crop Protection in Vineyard Cultivation

A study was conducted in the Jalna district of Maharashtra to assess the adoption pattern of spray technology, and safety awareness among grape growers. The respondents were selected through random sampling and data was collected through a structured interview. The study revealed that among marginal landholders (< 1 ha) back-pack type sprayer was mostly in operation with an adoption level of 75%. In small landholders (1-2 ha), horizontal triplex pump (HTP) sprayers with an adoption level of 51.85% followed by tractor-operated air-blast sprayers (40.75%) were prevalent pesticide spraying technologies. More than 2/3rd (76.00%) of medium landholders (2-4 ha) had adopted tractor-operated air blast sprayers. For the application of plant growth regulators, 62.5% of small farmers, 81.8% of medium, and 100% of farmers had adopted electrostatic sprayers. The number of chemical sprays per season varied from 25 to 100, making grapes one of the major pesticide-consuming crops. Capacity, efficiency, cost, and availability of sprayers on a custom hiring basis were the four major factors affecting the adoption of spraying technologies.

Growth, productivity and quality of colored capsicum (Capsicum annuum L.) as influenced by hybrids and plant growth regulators under controlled environment conditions

In developing countries like India, rapid urbanisation was under way and the diet habits of the people have been changing day to day. Under this transformation, a section of the population is focused on nutritional security where vegetables play a major role in daily diet. Among different vegetables coloured bell pepper which is commonly known as capsicum, has importance due to its nutritional quality and market demand. The quality and productivity of coloured capsicum can be improved by choosing the best performing hybrids and exogenous application of plant growth regulators. Considering the above, the present study was conducted from November to April of 2020-21 and 2021-22 at the Protected Cultivation Unit of Centurion University of Technology and Management, Paralakhemundi, Odisha under controlled environment conditions. The experiment was laid out in factorial randomized block design consisting of two hybrids, namely, Orobelle (yellow colored) and Bomby (red colored); and eight treatments of growth regulators which were GA3 @ 25 ppm, GA3 @ 50 ppm, GA3 @ 75 ppm, GA3 @ 100 ppm, NAA @ 20 ppm, NAA @ 40 ppm, NAA @ 60 ppm and NAA @ 80 ppm. A total of 16 treatment combinations were worked out in the experiment which were replicated thrice. The results of the experiment revealed that there was no significant variation among the hybrids cultivated with respect to yield attributes, yield, quality parameters and growth attributes excluding plant height and number of leaves per plant at 60 DAS and 90 DAS. However, there was a significant impact of plant growth regulators on growth attributes, yield attributes, yield and quality parameters. The application of NAA @ 80 ppm resulted in early flowering (43.8 days after planting). Moreover, the maximum number of flowers per plant (32.5 flowers/plant), flower to fruit ratio (52.9), fruits per plant (19.5) and weight of the fruit (133.6 g) recorded in GA3 @ 100 ppm application. There was a significant interaction effect among treatment combinations in fruit yield where the highest value was recorded in Bomby hybrid with GA3 @ 100 PPM application. From the study it may be concluded that cultivation of both the hybrids can be considered as per the fruit colour and market demand along with the application of GA3 @ 100 ppm under controlled environment conditions.

Metabolomics analysis reveals enhanced salt tolerance in maize through exogenous Valine-Threonine-Isoleucine-Aspartic acid application.

Salt stress is a well-known abiotic constraint that hampers crop productivity, affecting more than 424 million hectares of topsoil worldwide. Applying plant growth regulators externally has proven effective in enhancing crop resilience to salt stress. Previous metabolomics studies revealed an accumulation of Valine-Threonine-Isoleucine-Aspartic acid (VTID) in salt-stressed maize seedlings, suggesting its potential to assist maize adaptation to salt stress. To explore the effectiveness of VTID in enhancing salt tolerance in maize, 10 nM VTID was applied to salt-stressed maize seedlings. The results showed a remarkable 152.29% increase in plant height and a 122.40% increase in fresh weight compared to salt-stressed seedlings. Moreover, the addition of VTID enhanced the activity of antioxidant enzymes, specifically superoxide dismutase (SOD) and catalase (CAT), while reducing the level of malondialdehyde (MDA), a marker of oxidative stress. Additionally, VTID supplementation resulted in a significant increase in osmoregulatory substances such as proline. Metabolomic analysis revealed substantial changes in the metabolite profile of maize seedlings when treated with VTID during salt stress. Differential metabolites (DMs) analysis revealed that the identified DMs primarily belonged to lipids and lipid-like molecules. The receiver operating characteristic curve and linear regression analysis determined a correlation between isodolichantoside and the height of maize seedlings under salt-stress conditions. In conclusion, these findings validate that VTID effectively regulates tolerance in maize seedlings and offers valuable insights into the potential of short peptides for mitigating salt stress.

The effect of foliar application of plant growth regulators on functional and qualitative characteristics of wheat (Triticum aestivum L.) under salinity and drought stress conditions

This study aimed to investigate the effect of salinity and water stress on the physiological and functional characteristics of winter wheat (Triticum aestivum L.) under the foliar application of plant growth regulators (PGRs). The experiment was carried out as a split plot based on a randomized complete block design with three replications in two environments. In each environment, water stress at two irrigation levels (after 90 and 120 mm of pan evaporation) and with two EC of 1.5 and 10 dS/m in the main plots and spraying of PGRs including salicylic acid (SA), gibberellic acid (GA3), and cytokinins (CK) (purine) content with a concentration of 100 ppm and the control treatment (spraying solution with normal water) were placed in subplots. Results indicated that all treatments caused significant increases in functional and qualitative characteristics and yield of Triticum aestivum L. The saline environment and irrigation level after 120 mm of pan evaporation caused a reduction in grain yield in all traits except for seed proline, seed nitrogen content, and seed protein content. Also, the combined foliar application of GA3 + CK + SA increased yield in most traits. The highest RWC of flag leaves was observed in the foliar application of GA3 + SA (3.36 kg/ha) and then in the foliar application of GA3 + SA + CK (57.87 kg/ha). GA3 interacts with PGR spraying to balance another development under saline and non-saline conditions.

Effect of Foliar Application of Selected Plant Growth Regulators on Growth and Yield of Soybean [Glycine max (L.) Merrill

Background: Soybean (Glycine max), a prized oilseed crop known for its nutritional richness, is the focus of a study aiming to boost production with minimal environmental impact. The research explores the application of plant growth regulators (PGRs), specifically Gibberellic Acid (GA3), Kinetin and Salicylic Acid, in field experiments during the kharif seasons of 2022 and 2023 in Beed, India. Methods: The study applied Gibberellic Acid (GA3), Kinetin and Salicylic Acid at different concentrations in field experiments. A comprehensive analysis of growth and yield attributes, including plant height, primary branches, Leaf Area Index (LAI), root nodules and Crop Growth Rate (CGR), was conducted to assess the influence of PGR treatments on soybean growth. Yield attributes such as pod count, pod weight, seed count per pod and 100-seed weight were scrutinized to understand their effects on soybean productivity. Result: The study highlighted significant effects of PGR treatments on soybean growth and yield. Notably, Kinetin at 500 ppm promoted the tallest plants, while GA3 at 200 ppm resulted in the shortest. Kinetin at 100 ppm increased primary branches and Salicylic Acid at 50 ppm exhibited the highest LAI and abundant root nodules. Kinetin at 500 ppm and Salicylic Acid at 50 ppm showed higher CGR, indicating efficient crop growth. For yield, Kinetin at 500 ppm excelled in pod count and weight. GA3 at 100 ppm was identified as the most effective PGR for enhancing various growth parameters and soybean seed yield, suggesting the potential of PGRs in sustainable cultivation, reducing reliance on chemical inputs.

Fertiliser supplementation with a PGR complex of chlormequat chloride (CCC) and paclobutrazol (PBZ) alters Cannabis sativa growth

ABSTRACT Cannabis (Cannabis sativa) is a high-value crop, wherein growth within controlled environments is common for the purposes of maximising yield, quality, and uniformity, however, uncontrolled-growth in proximity to artificial lighting can compromise yields. Within the floricultural industry it is common practice to apply plant growth regulators (PGRs) to retard plant growth and maximise yield and quality, with two well-established PGRs being chlormequat chloride (CCC) and paclobutrazol (PBZ). Accordingly, the aim of this study was to investigate the potential of a PGR complex of CCC and PBZ for novel application to cannabis to control plant height. Treatment of cannabis with the PGR complex within an indoor hydroponic growth system resulted in a 91.1% reduction in post-treatment plant growth (p < 0.001) leading to plants with end-point height and internodal spacing (INS) 0.568-fold (p < 0.001) and 0.469-fold (p < 0.001) shorter than control plants, respectively. These results demonstrate the capacity of CCC and PBZ to beneficially halt the growth of cannabis. Accordingly, application of these PGRs in combination may be utilised to restrict cannabis height without compromising yield within commercial cultivation.

Successful shoot tip grafting of cacao (Theobroma cacao L.) due to the application of plant growth regulators on various concentrations

Cacao plays an important role in the Indonesia economy. Therefore, its production and area expansion have to increase to achieve maximum cacao productivity by the quality and superior cacao clones. Shoot tip grafting is one of the propagation methods to obtain superior cacao plants by applying Plant Growth Regulators (PGRs). Research on the effect of several PGRs with various concentrations on cacao (Theobroma cacao L.) shoot tip grafting was conducted at the Integrated Innovation Farmer Group, Belubus, Sungai Talang Village, Guguak District, Lima Puluh Kota Regency, West Sumatra from February until June 2022. This study aimed to determine the interaction between PGR type and concentration on the grafting success and growth of cacao shoot tip grafted seedling. The research was designed by a Factorial Completely Randomized Design with three replications. The first factor was the type of PGR, i.e., synthetic PGR (BAP), young corn seed extract, shallot extract, and young coconut water. The second factor was the concentration of PGR, i.e., 0%, 25%, 50%, 75% and 100%. The results showed an interaction between PGRs with some concentrations on the number of shoots, shoot length, and leaf length on the grafted cacao seedling. The natural PGR from young coconut water at a concentration of 75% gave the best effect on the number of shoots (3.33 shoots) and shoot length (24.50 cm) of cacao seedling.

The application potential of mepiquat chloride in soybean: improvement of yield characteristics and drought resistance

BackgroundDrought can result in yield losses, the application of plant growth regulators is an effective measure to improve drought resistance and yield. The objective of the study was to explore the application potential of mepiquat chloride (MC) in regulating soybean yield and drought resistance.MethodsIn this study, a three-year field experiment was designed and combined with drought experiments to measure the yield of popularized varieties during 2021–2022 and drought-resistant and drought-sensitive varieties were selected, and planted in the field in 2023.ResultsMC increased the yield of HN84 and HN87 for two consecutive years from 2021 to 2022 and improved their physiological characteristics under field conditions. Under M200 treatment, the yield of HN84 increased by 6.93% and 9.46%, and HN87 increased by 11.11% and 15.72%. Different concentrations of MC have different effects on soybeans. The maximum increase of SOD, POD and proline in HN84 under M400 treatment reached 71.92%, 63.26% and 71.54%, respectively; the maximum increase of SOD, POD and proline in HN87 under M200 treatment reached 21.96%, 93.49% and 40.45%, respectively. In 2023, the foliar application of MC improved the physiological characteristics of HN44 and HN65 under drought-stress conditions. On the eighth day of drought treatment, compared to the drought treatment, the leaf and root dry weight of HN44 under M100 treatment increased by 17.91% and 32.76%, respectively; the dry weight of leaves and roots of HN65 increased by 20.74% and 29.29% under M200 treatment, respectively. MC also reduced malondialdehyde (MDA) content, decreased antioxidant enzyme activity and proline content. In addition, different concentrations of MC increased the chlorophyll fluorescence parameters (Fs, Fv/Fm, YII, and SPAD). In the field, the plant height of the two varieties decreased significantly, the yield increased, the number of two-grain and three-grain pods increased, and the stem length at the bottom and middle decreased with MC induction.ConclusionsThe application of 100–200 mg/L MC effectively improved drought resistance and increased yield. This study provided support for the rational application of MC in soybean production.

Screening of Atrazine Tolerant Aquatic Plant and Roles of Plant Growth Regulators on Plant Growth and Atrazine Tolerance

The extensive use of atrazine to control weeds in agricultural areas has contaminated atrazine in surface water and groundwater. Atrazine contamination in water resources causes human health concerns. Thus, this study investigated the possible use of aquatic plants for removing atrazine from contaminated water. The experiment was performed under plant nursery conditions and divided into two parts: (1) the atrazine-tolerant plants were screened, and (2) the most atrazine-tolerant plant was used for atrazine phytoremediation stimulated by plant growth regulators. The results showed that atrazine was toxic to all aquatic plants, as the dry weight of the plants was significantly decreased when exposed to 20 mg/L of atrazine (P&lt;0.05). Based on five aquatic plants grown under 2.5–20 mg/L atrazine-contaminated water, &lt;i&gt;Azolla microphylla&lt;/i&gt; Kaulf. was the most tolerant aquatic plant and was more suitable for use in atrazine phytoremediation than the other aquatic plants (&lt;i&gt;Ceratophyllum demersum&lt;/i&gt; L., &lt;i&gt;Eichhornia crassipes&lt;/i&gt; (Mart.) Solms, &lt;i&gt;Hydrilla verticillata&lt;/i&gt; (L. f.) Royle, and &lt;i&gt;Salvinia cucullata&lt;/i&gt; Roxb. ex Bory). The total chlorophyll, carotenoid, and proline contents in the biomass of &lt;i&gt;A. microphylla&lt;/i&gt; cultured in 2.5–20 mg/L of atrazine did not significantly differ between the atrazine concentrations (P&gt;0.05). Meanwhile, the proline contents in the other four aquatic plants increased with increasing atrazine concentrations, and the chlorophyll content significantly decreased with an increase in the atrazine concentration. However, &lt;i&gt;A. microphylla&lt;/i&gt; could not remove atrazine from contaminated water, and the application of plant growth regulators (6-benzyladenine, gibberellic acid, indole-3-butyric acid, and salicylic acid) did not improve the atrazine removal from water. Atrazine in the water was around 21–26 mg/L on day five of &lt;i&gt;A. microphylla&lt;/i&gt; cultivation compared to the initial concentration (25 mg/L). Using a plant growth regulator was ineffective for stimulating growth and atrazine removal by &lt;i&gt;A. microphylla&lt;/i&gt;. Future research should explore other potential mechanisms for enhancing atrazine removal by &lt;i&gt;A. microphylla&lt;/i&gt;.

Exogenous melatonin delays leaves senescence and enhances saline and alkaline stress tolerance in grape seedlings

ABSTRACT Saline and alkaline stress is one of the major abiotic stresses facing agricultural production, which severely inhibits the growth and yield of plant. The application of plant growth regulators can effectively prevent crop yield reduction caused by saline and alkaline stress. Exogenous melatonin (MT) can act as a signaling molecule involved in the regulation of a variety of physiological processes in plants, has been found to play a key role in enhancing the improvement of plant tolerance to abiotic stresses. However, the effects of exogenous MT on saline and alkaline tolerance of table grape seedlings and its mechanism have not been clarified. The aim of this study was to investigate the role of exogenous MT on morphological and physiological growth of table grape seedlings ( Vitis vinifera L.) under saline and alkaline stress. The results showed that saline and alkaline stress resulted in yellowing and wilting of grape leaves and a decrease in chlorophyll content, whereas the application of exogenous MT alleviated the degradation of chlorophyll in grape seedling leaves caused by saline and alkaline stress and promoted the accumulation of soluble sugars and proline content. In addition, exogenous MT increased the activity of antioxidant enzymes, which resulted in the scavenging of reactive oxygen species (ROS) generated by saline and alkaline stress. In conclusion, exogenous MT was involved in the tolerance of grape seedlings to saline and alkaline stress, and enhanced the saline and alkaline resistance of grape seedlings to promote the growth and development of the grape industry in saline and alkaline areas.

Exogenous application of bio-stimulants and growth retardants improve nutrient absorption and fiber quality in upland cotton

BackgroundNatural and synthetic plant growth regulators are essential for plant health, likewise these regulators also play a role in increasing organic production productivity and improving quality and yield stability. In the present study, we have evaluated the effects of foliar applied plant growth regulators, i.e., moringa leaf extract (MLE) and mepiquat chloride (MC) alone and in combination MC and MLE on the conventional cotton cultivar (CIM 573) and transgenic one (CIM 598). The growth regulators were applied at the start of bloom, 45 and 90 days after blooming.ResultsThe application of MC and MLE at 90 days after blooming significantly improved the relative growth rate, net assimilation rate, the number of bolls per plant, and seed cotton yield. Likewise, the combined application of MLE and MC at 90 days after blooming significantly boosted the nitrogen uptake in locules, as well as the phosphorus and potassium uptake in the leaves of both cotton cultivars. The application of MLE alone has considerably improved the nitrogen uptake in leaves, and phosphorus and potassium contents in locules of Bt and conventional cotton cultivars. Similarly, Bt cotton treated with MLE at 90 days after blooming produced significantly higher ginning out turn and oil contents. Treatment in combination (MLE + MC) at 90 days after blooming produced considerably higher micronaire value, fiber strength, and staple length in conventional cultivar.ConclusionThe natural growth enhancer, MLE is a rich source of minerals and zeatin, improving the nutrient absorption and quality of cotton fiber in both conventional and Bt cotton cultivars.

Autonomous differentiation of transgenic cells requiring no external hormone application: the endogenous gene expression and phytohormone behaviors.

The ectopic overexpression of developmental regulator (DR) genes has been reported to improve the transformation in recalcitrant plant species because of the promotion of cellular differentiation during cell culture processes. In other words, the external plant growth regulator (PGR) application during the tissue and cell culture process is still required in cases utilizing DR genes for plant regeneration. Here, the effect of Arabidopsis BABY BOOM (BBM) and WUSCHEL (WUS) on the differentiation of tobacco transgenic cells was examined. We found that the SRDX fusion to WUS, when co-expressed with the BBM-VP16 fusion gene, significantly influenced the induction of autonomous differentiation under PGR-free culture conditions, with similar effects in some other plant species. Furthermore, to understand the endogenous background underlying cell differentiation toward regeneration, phytohormone and RNA-seq analyses were performed using tobacco leaf explants in which transgenic cells were autonomously differentiating. The levels of active auxins, cytokinins, abscisic acid, and inactive gibberellins increased as cell differentiation proceeded toward organogenesis. Gene Ontology terms related to phytohormones and organogenesis were identified as differentially expressed genes, in addition to those related to polysaccharide and nitrate metabolism. The qRT-PCR four selected genes as DEGs supported the RNA-seq data. This differentiation induction system and the reported phytohormone and transcript profiles provide a foundation for the development of PGR-free tissue cultures of various plant species, facilitating future biotechnological breeding.

Effect of foliar application of trace elements and growth regulators on plant biomass and symbiotic efficiency of Lens culinaris M.

The present study was conducted to assess the impact of foliar application of plant growth regulators (IAA and GA3) and trace elements (ZnSO4 and boric acid) on shoot and root length and nodulation efficiency in Lentil (Lens culinaris). Results indicated that significantly (p ≤ 0.05) higher shoot and root length, nodule numbers plant−1 (77.0 ± 1.93 cm, 25.0 ± 1.10 cm and 31.0 ± 1.82, respectively) were recorded with foliar application of IAA @50 ppm concentration followed by IAA @ 25 ppm as compared to IAA@100 ppm and control treatment at fruiting stage of lentil. Similar trends have been seen with the application of GA3. At fruiting stage of lentil, significant (p ≤ 0.05) enhanced shoot length (21.35%), root length (11.76%) and nodule number plant−1 (180%) was observed with the foliar application of GA3 @50 ppm over the control treatment of lentil. Present study demonstrated that shoot and root length, nodule numbers plant−1 was markedly reduced at higher concentration. In the case of zinc sulphate and boric acid, significantly (p ≤ 0.05) higher shoot and root length, nodulation efficiency was recorded with zinc sulphate (ZnSO4) @ 50 ppm and boric acid @ 50 ppm in contrast to ZnSO4 @100 ppm and control treatment. Current study reported first time, results indicate that impact of plant growth regulators, and trace elements on nodulation and growth in lentil are totally concentration-dependent. Further, research is needed to understand the underlying mechanisms and the optimum application concentrations for an improved crop performance under field conditions.