Application Of Growth Regulators Research Articles

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.

Study on droplet deposition characteristics and application of small and medium crown garden plants sprayed by UAV sprayer

The Unmanned Aerial Vehicle (UAV) sprayer has the advantages of high work efficiency, simple operation, and high safety factor, and has broad application prospects UAV sprayer are widely used in the agricultural field, and the application of UAV sprayer spraying technology in agriculture has provided convenience and increased profits for farmers, and has also become a research hotspot in the field of agriculture. In recent years, although research has been conducted on the feasibility and application effects of UAV sprayer spraying crown shaped plants, there have been no experiments or studies in the field of garden plants. This experiment conducted a droplet deposition experiment of UAV sprayer spraying garden plants, exploring the droplet deposition effect of UAV sprayer in the field of garden plants, and conducting experiments on the influence of spray volume and nozzle type on droplet deposition. The experimental results showed that the canopy performance of small and medium-sized garden plants was better at a flight altitude of 1.5m, a spray volume of 180L/hm2, and a flight speed of 2m/s. Reducing flight altitude, increasing spray volume, and reducing flight speed can improve the distribution of droplets in the canopy. This experiment lays the foundation for the application of UAV sprayer for the prevention and control of pests and diseases in garden plants, as well as for the application of growth regulators, and provides a basis for further innovative research in the field of garden plant application technology.

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.

Application of Insect Growth Regulators (IGRs) as Biopesticides for Sustainable Agriculture

The application of conventional pesticides is underlined by many negative externalities including environmental degradation and pest resistance. Consequently, use of biopesticides as alternative agrochemicals is recommended to meet sustainable development goals. Insect growth regulators (IGRs) are biochemical biopesticides. Actually, Biochemical biopesticides are compounds (or exact synthetic analogue) of natural origin possessing active ingredients that control pest in a way that are nontoxic to the target pest, the environment and humans. So, insecticides with growth regulating properties may adversely affect insects by regulating or inhibiting specific biochemical pathways or processes essential for insect growth and development. Ecdysoids and Juvenoids (JH mimics) are among the most promising IGRs. Ecdysoids are synthetic analogues of natural ecdysone and when applied in insects, kill them by formation of defective cuticle. Juvenoids (JH mimics) are synthetic analogues of Juvenile Hormone (JH). Juvenoids have anti-metamorphic effect on immature stages of insect. Along with this, Anti JH or precocenes which act by destroying corpora allata and preventing JH synthesis also act as IGR. In this way, Insect Growth Regulators are potential substitute of insecticides that could be commercially used.

Assessing Impact of Manual Topping and Suckericide Application at Different Stages on FCV Tobacco Quality and Yield

Tobacco (Nicotiana tabacum L.) topping is one of the essential practice to obtain good quality and adequate yield. The suckericide (Flumetralin as a best herbicide and plant growth regulator). For the purpose to compare topping as manual and herbicide application the experiment was conducted on flue cured Virginia (FCV) tobacco at Tobacco Research Station, Khan Ghari, Mardan during 2021-2022. The experiment was conducted in RCB design with three replications and five treatments (Control, Manual de-suckering, 1000, 1200, 1500 ml of Flumetralin ha-1). Treatments were applied at three stages (button stage, early flowering stage and late flowering stage). The data revealed that topping timing and maximum dose (1500 ml ha-1) of (Flumetralin) resulted maximum (896 cm-2) leaf area, less number (14) of sucker plant-1, lower (132 g) green weight and dry weight (20.30 g) of sucker plot-1, more cured weight (5.08 kg) of leaves plot-1 and maximum yield (3038) kg ha-1, lower nicotine contents (2.26) and less sugar contents (16.24) at button stage. Moreover, Flumetralin application on at button stage resulted less sucker growth and enhanced leaf yield. I suggest that the tobacco K399 with the application of suckericide and growth regulator (Flumetralin) have the potential to incorporate in further breeding program for low content of nicotine, reduced sugar content and high yield.

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<0.05). Based on five aquatic plants grown under 2.5–20 mg/L atrazine-contaminated water, <i>Azolla microphylla</i> Kaulf. was the most tolerant aquatic plant and was more suitable for use in atrazine phytoremediation than the other aquatic plants (<i>Ceratophyllum demersum</i> L., <i>Eichhornia crassipes</i> (Mart.) Solms, <i>Hydrilla verticillata</i> (L. f.) Royle, and <i>Salvinia cucullata</i> Roxb. ex Bory). The total chlorophyll, carotenoid, and proline contents in the biomass of <i>A. microphylla</i> cultured in 2.5–20 mg/L of atrazine did not significantly differ between the atrazine concentrations (P>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, <i>A. microphylla</i> 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 <i>A. microphylla</i> cultivation compared to the initial concentration (25 mg/L). Using a plant growth regulator was ineffective for stimulating growth and atrazine removal by <i>A. microphylla</i>. Future research should explore other potential mechanisms for enhancing atrazine removal by <i>A. microphylla</i>.

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.

Study on Tissue Culture and Rapid Propagation Techniques of Different Explants of Codonopsis convolvulacea Kurz

The tissue culture technology of Dioscorea bulbifera L. is of great significance for the effective protection and utilization of its germplasm resources. This paper reviews the research progress of tissue culture technology of Dioscorea bulbifera L. with different explants. It introduces the historical development of tissue culture technology of Dioscorea bulbifera L., including early exploration and gradual improvement of modern technology. The paper elaborates various methods and strategies of tissue culture technology of Dioscorea bulbifera L. at present, including research progress in aspects such as explant selection, medium formulation, and application of growth regulators. It also looks forward to the future development direction and potential applications of tissue culture technology of Dioscorea bulbifera L., and discusses its application prospects in germplasm resource preservation, new variety breeding, and improvement of disease and pest resistance. This paper is of important theoretical and practical significance for promoting the research and application of tissue culture technology of Dioscorea bulbifera L.

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.

A Review on Effect of Bio-fertilizers and Chemical Fertilizers on Growth, Yield and Quality of Dioecious Cucurbits

No vegetable group in India is as diverse as the cucurbits. They are adapted to diverse soil and climate condition and contribute significantly to total vegetable production. Dioecious cucurbits cultivation merge with trellising, staking, mulching, application of biofertilizers and growth regulators hold immense potential and promise for future vegetable production and market in our country. Biofertilizer can be defined as a substance which contains living organisms which, when applied to seed, plant surface, or soil, colonize the rhizosphere or interior of the plant, and promote growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers are an chief component of integrated nutrient management system for sustainable agriculture and along with chemical fertilizers. Studies suggest that cultivation of dioecious cucurbits along with chemical and organic fertilizers gives immense result on account of yield and productivity. Our country possesses a rich diversity like spine gourd, ivy gourd, bitter gourd, sweet gourd, pointed gourd and has ideal climate and soil to cultivate these cucurbits. Mostly these miner cucurbits are largely grown or wild gathered and sold in the market by small and marginal farmers. Hence promotion of these cucurbits holds key to ensuring livelihood security and income generation for to the tribal’s, marginal and small farmers in remote rural regions. Dioecious cucurbits mainly possess different important chemical compounds which can be used in nutraceuticals industries. These cucurbits has the potential to act as a source of income generation for rural farmers as they have immense market potential. These cucurbits need strong research support for better production and utilization.

Battling arid adversity: unveiling the resilience of cotton in the face of drought and innovative mitigation approaches

Climate change has had significant impacts on agriculture, particularly on cotton production, where drought has emerged as a major threat worldwide. Long and intense dry periods in cotton-growing regions have become more frequent and severe. Drought stress severely affects various aspects of cotton plants, including chlorophyll pigments, carbohydrate metabolism, and enzyme activities related to fiber development, such as vacuolar invertase and sucrose synthase. Furthermore, drought stress disrupts the movement of nutrients toward the reproductive tissues in cotton, resulting in compromised pollen function, propagative failure, and fiber characteristics. To tackle these issues, scientists have made advancements in creating drought-resistant cotton varieties through transgenic methods or molecular breeding techniques, genome editing, CRISPR/Cas9, utilizing quantitative trait loci (QTL). Moreover, the application of plant growth regulators and mineral elements has displayed the potential to improve cotton’s ability to endure drought stress while also enhancing fiber yield and quality. These approaches activate stress-responsive signaling pathways, which could contribute to mitigating reproductive failure and improving fiber characteristics. While the impact of drought stress on cotton plants has been extensively studied, the variations in fiber quality resulting from drought stress are not yet completely understood. Current research has been focused on unraveling the mechanisms underlying these changes, including the physiological, biochemical, and molecular alterations during the multiplicative growth phase that contribute to poor fiber development. Understanding these mechanisms will facilitate the development of novel strategies to alleviate the adverse impact of worldwide weather changes on cotton growth and fiber quality. This research focuses on the drought stress in cotton cultivation and explores its different effects on cotton morphology, physiology, crop yield, and fiber characteristics as well as mechanisms by which cotton exhibits drought tolerance and highlights innovative strategies to mitigate drought stress.

Developing Drought Tolerance in Field Crops towards Current Century: An Integrated Bio-Molecular Approach

Drought stresses are foremost threat to plant growth, productivity as well as sustainability towards agriculture through worldwide. Some of the classical breeding approaches have been attempted to develop crop performance towards stress without significant success and so therefore, recently genetic engineering in crop plants is recognized as an alternative strategy to generate drought tolerant crop plants. Various integrated biological approaches have been undertaken to overcome such drought hurdles in achieving the full potentiality of the plant growth and production as well as improving the drought tolerance in different field crops. Some approaches are commonly used to identify genes related to drought tolerance and genes to be identified which are involved in processes known to be critical for drought tolerance; whose expression is regulated by drought stress and that consists in the identification of drought tolerance determinants based on functionality. Plant researchers have developed several spurts of biological novel ‘Omics’ technologies viz. genomics, transcriptomics, proteomics and metabolomics etc to engineer plant stress tolerance. In this review, an attempt has been made to summarize the current information based on recent literature towards recent understanding as well as latest advancement related to the adverse effect of plant under drought and their adaptations or tolerance towards such abiotic stress with a focus on the identification of drought tolerance mechanisms by soil management practices, crop establishment and exogenous application of growth regulators by regulating an appropriate level of water due to osmotic adjustment and stomatal performance etc at an integrated biological level of approach.

Flowering Behaviour and Synchronization in Avocado: A Comprehensive Review

Understanding the flowering behaviour and synchronisation in avocado (Persea americana) is crucial for effective orchard management as it directly impacts fruit yield and quality. The flowering patterns of avocado trees are influenced by a variety of factors, including genetics, environment, and cultural practices. In this review, we will delve into the various factors that influence avocado flowering, with a particular focus on the physiological and environmental aspects. It is crucial to highlight the significance of maintaining optimal tree health and providing a well-balanced nutrition for successful avocado flowering. In this discussion, we will explore the role of chilling requirements, temperature, and photoperiod in flower initiation and development. An analysis is conducted on cultivation practices, specifically pruning and girdling, to assess their effects on flower synchronisation. While some practices, such as plant growth regulator applications, may offer potential avenues for manipulation, their efficacy in the context of avocado flowering remains a subject of ongoing research. This abstract highlight the importance of gaining a thorough understanding of avocado flowering dynamics in order to create sustainable orchard management strategies. By improving flower synchronisation, we can ultimately maximise fruit production in avocado cultivation.

Incision in the base and indolebutyric acid to promote the rooting of 'Bengal' litchi cuttings

A alternative to producing litchi (Litchi sinensis Sonn.) seedlings is by cuttings. However, the main drawback of using this method is related to the difficulty of rooting presented by this species. Thus, the objective of this study was to evaluate the rooting of semihardwood cuttings of litchi ‘Bengal’ at different concentrations of indolebutyric acid, with or without incision in the base. The experimental design was completely randomized with five replicates of 10 cuttings in a factorial 3X2 (three IBA concentrations: 0, 1.000 and 2.000 mg L-1; with or without incision in the base). After 126 days, the variables evaluated were: cutting survival, leaf retention, cutting with callus not rooted, rooted cutting, number of roots per cutting, length of major roots per cutting and dry weight of roots per cutting. For rooting, the IBA application was efficient only when the cuttings were not injured. In addition, there was no influence of the types of cuttings in the IBA concentrations. However, in those with incision at the base, the means were higher without the application of the plant growth regulator. Thus, the 'Bengal' litchi can be multiplied by semihardwood cuttings with incision at the base of the cuttings, without the use of IBA.

Exogenous Application of Plant Growth Regulators Improves Economic Returns, Grain Yield and Quality Attributes of Late-Sown Wheat under Saline Conditions

Exogenous Application of Plant Growth Regulators Improves Economic Returns, Grain Yield and Quality Attributes of Late-Sown Wheat under Saline Conditions

Comparative analysis of exogenously applied synthetic auxins and micronutrients for effective management of fruit drop and quality improvement in subtropical Japanese plum (Prunus salicina Lindl.)

Foliar application of plant growth regulators and micronutrients is a rapid uptake strategy of plant-feeding directly through leaves irrespective of soil condition. This experiment was conducted to assess the impact of the foliar application of synthetic auxins and micronutrients on subtropical Japanese plum (Prunus salicina Lindl.) fruit yield and quality. The experiment was performed in a plum orchard based on a completely randomized block design with nine treatments and three replications. The foliar treatments included NAA 15 ppm, NAA 15 ppm + urea 2%, 2,4-D 10 ppm, 2,4-D 10 ppm + urea 2%, borax 0.50%, borax 0.50% + urea 2%, ZnSO4 0.50%, ZnSO4 0.50% + urea 2%, and control (sprayed with distilled water) applied as a two spray in 15 days interval after fruit set. Foliar application of NAA 15 ppm + urea 2% led to least fruit drop followed by highest fruit yield. The fruit physicochemical attributes including fruit length and diameter, fruit weight, pulp weight, total soluble solids, titratable acidity, sugars, and ascorbic acid were also significantly improved by foliar spray of NAA 15 ppm + urea 2%. However, all the treatments were ineffective in improving anthocyanin and total phenol content of ‘Satluj Purple’ plum. The results further revealed that reduced fruit drop followed by highest fruit yield with foliar application of NAA 15 ppm + urea 2% was associated with reduced activity of cell wall degrading enzymes viz., cellulase and polygalacturonase at abscission zone.