Spray Application Research Articles

Measuring ornamental tree canopy attributes for precision spraying using drone technology and self-supervised segmentation

Tree canopy attributes or characteristics, such as canopy volume and density, are important parameters for calculating the precise quantity of agrochemicals required in each tree. Assessing the agrochemical needs in a nursery can help growers effectively estimate expenses, mitigate the risks of overuse or underuse, enhance resource utilization, and promote sustainable agricultural practices. This study aimed to develop an unmanned aerial vehicle (UAV)-based system to measure tree canopy attributes like tree height, tree count, canopy area and canopy volume using an image processing and self-supervised zero-shot segmentation approach. A high-resolution red-green-blue (RGB) sensor mounted on a drone captured three aerial image datasets, D1 and D2 from the first experimental plot and D3 from the second experimental plot. The acquired aerial images were stitched together and processed to generate a digital surface model (DSM) and a digital terrain model (DTM). A self-supervised zero-shot segmentation model, Segment Anything Model (SAM), was applied for tree segmentation and counting. The tree canopy area was calculated by segmenting individual trees and applying a conversion factor to convert pixelwise areas into square meters. Height calculation was done using elevation data of each pixel from DSM-DTM imagery within SAM-derived bounding box coordinates, and the highest pixel was considered as the height of the tree. The drone-calculated heights of 24 randomly selected trees were compared with manually measured heights in all datasets. The results showed an average absolute error of 2.43% in D1, 7.09% in D2 and 12.58% in D3. The Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were noted to be 0.09 m and 0.23 m in D1, 0.13 m and 0.25 m in D2, and 0.16 m and 0.21 m in D3, respectively. In D3, manual area and volume calculations were performed for validation. The RMSE and MAE for area calculation were calculated as 0.18 m2 and 0.15 m2, respectively, and the RMSE and MAE for volume measurements were calculated as 0.33 m3 and 0.26 m3 respectively, which indicated the level of agreement between manual and drone measurements. Using canopy volume information, calculated by summing pixel heights within each tree’s bounding box and multiplying by the ground sample distance (GSD) of 0.025 m per pixel, the average quantity of agrochemicals needed for a Maple tree was estimated at 0.20 L. These results underscore the high potential of this method for accurate canopy characteristic calculations and precision spray applications in the ornamental industry.

Perseverance of management is needed – Efficient long-term strategy of Reynoutria management

One of the most problematic invasive species in Europe are knotweeds from genus Reynoutria (Fallopia) which have significant negative impact on the native communities as well on human activities. Therefore, they are a target of many control programmes. Due to their high regeneration potential, their management is problematic, and only chemical treatment is reported to be sufficiently effective. The aim of this paper was to describe and analyse the patterns of Reynoutria invasion under long-term chemical treatment with glyphosate-based herbicide in The Morávka river floodplain, Czech Republic. The data covers 17 years of management which started with the European project “Preservation of alluvial forest habitats in the Morávka river basin”. We focus on (i) assessment of Reynoutria distribution during long-term management, (ii) analysis of the change of distribution according to the habitat, and (iii) discussion of the optimal management strategy based on the long-term data. Distribution data was obtained using GNSS field mapping. Before the start of the study in 2007, Reynoutria stands covered 29% of the study area (96.9 ha). As a result of systematic whole area chemical management, the extent decreased to 19.6% (65.3 ha) in 2009, and even reached 14.5% (48.2 ha) in 2013, three years after its end. Due to implementation of local chemical management in the following years, the area of Reynoutria was maintained at similar level, with minimum value 41.8 ha in 2018 and a slight increase in recent mapping in 2023. Beside the extent, the structure and coverage of invaded sites was analysed. There was a clear trend of fragmentation of larger polycormons with high coverage into many smaller and less dense ones as a result of chemical spraying. The average size of Reynoutria stand decreased from 0.61 ha in 2007 to half in 2013 (0.32 ha) to 0.15 ha in 2023. Testing of the effects of time, habitat, and biotope did not reveal significant differences of changes of extent and abundance over different environments (forest, open, bare ground), which indicates that there are no differences in reaction to management in the studied habitat and vegetation types. Our study provides a robust and unique overview of the invasion, reinvasion, and suppression dynamics for an important invasive species. If herbicide management is used, chemical treatment must be quite long-term as even three years of intensive glyphosate foliar spray application was not sufficient for the complete eradication of Reynoutria. Therefore, we propose the following procedure for effective chemical management of Reynoutria: 1) In largely infested sites, the first step is to reduce the distribution of Reynoutria stands to isolated polycormons. This phase can last 3–5 years. 2) After reaching the state of sparse distribution of Reynoutria, we recommend herbicide application only in periods of every 3–5 years depending on the local context and rate of regrowth. 3) At sites exposed to soil disturbances, where the soil is contaminated by fragments of Reynoutria rhizomes, there is a need to apply herbicide immediately to target newly resprouting individuals.

Deep learning guided variable rate robotic sprayer prototype

This paper presents the development of a robotic sprayer that combines artificial intelligence with robotics for optimal spray application on citrus nursery plants grown in an indoor environment. The robotic platform is integrated with an embedded firmware of MobileNetV2 model to identify and classify the plant samples with a classification accuracy of 100 % which is used to dispense variable rate spraying of pesticide based on the health status of the plant foliage. The disease detection model was developed through the edge impulse platform and deployed on Raspberry Pi 4. The robot navigates through an array of plants, stops beside each plant, and captures an image of the citrus plants. It feeds the image into the deployed embedded model to generate a disease inference that informs the variable rate application of spray during real-time actuation. To test the spraying performance of the prototype within the growing environment, water sensitive cards were placed in each plant's canopy. After spraying, the samples of water sensitive cards were collected and quantified using a smart spray app to determine the classification accuracy as well as the extent of spray coverage on the citrus samples. The robot spray coverage results show an average spray coverage of 87 % on lemon foliage when compared with 67 % for navel orange, during the spray performance test of the robot.

Improving oral delivery of ciprofloxacin through in situ spray drying and acid counterions

This study explores the application of a novel three-fluid nozzle spray drying technique in formulating in situ ciprofloxacin (CFX) salts for improved oral drug delivery. The used key materials in the study include CFX combined with four different counterions: succinic acid (SA), glutaric acid (GA), adipic acid (AA), and pimelic acid (PA), alongside hydroxypropyl methylcellulose (HPMC) as a matrix agent. The process utilized a three-fluid nozzle spray drying technique to produce CFX salts directly with these acids during the process, creating three types of formulations: pure salts (SALT), solutions of drug and polymer (SOL), and nanoprecipitates of drug within a polymer matrix (SUS). Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM) analyses revealed that the formulations predominantly exhibited an amorphous structure with varied particle shapes and sizes. The dissolution profiles of CFX salts show a marked burst release within the initial 5 min, with CFX-GA leading at nearly double the release rate of CFX-AA, after which all formulations rapidly achieve over 90 % dissolution and maintain a stable release up to 30 min. This pattern was attributed to the interactions between the drug salts and HPMC, resulting in a sustained release of CFX. In vivo experiments with rabbits revealed a higher plasma concentration of CFX for CGAH-sus compared to CGAH-sol, highlighting the enhanced bioavailability of the SUS formulation. The amorphous nature of CGAH-sus, with ionization confirmed through Raman spectroscopy, facilitated efficient drug release and absorption in the gastrointestinal tract. This study illustrates the effectiveness of the three-fluid nozzle spray drying method in producing salts with varied physical properties and dissolution profiles, holding potential for advanced oral drug delivery systems.

In Vivo Efficacy of Bioagents and Fungitoxicants against False Smut Disease of Rice Caused by Ustilaginoidea virens (Cooke) Takahashi

The present experiment was conducted from June to November 2017 at Crop Research Center, Chirodi, Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut (U.P.), India to assess the efficacy of six fungicides-propiconazole, strobin, flutolanil, copper oxychloride, azoxystrobin, flusilazol, and two bioagents viz., Trichoderma harzianum and Pseudomonas fluorescens-against false smut of rice under natural epiphytotic field conditions. Once panicle emergence reached 50%, each fungicide and bioagent was sprayed once. The findings of present investigation revealed that spray of propiconazole @ 0.1% reduced the false smut significantly and resulted in the lowest percentage of infected tillers (7.48%) and smutted grains (4.98%) along with maximum yield parameters like number of tillers (294), 10-ears weight (30.10 g), 1000-grain weight (24.50 g) and yield (4903 kg ha-1); it was followed by the spray application of either azoxystrobin @ 0.07% or strobin @ 0.06% with above respective parameters. Apart from the fungicides applied, the application of Trichoderma harzianum also reduced the false smut and increased the yield components significantly over the control plots. However, the lowest 10-ear weight (22.80 g), 1000-grain weight (17.50g), and yield (3100 kg ha-1) along with the highest percentage of infected tillers (23.93%) and smutted grains (21.47%) were recorded in unprotected plots. Therefore, growers can be advised to use a foliar spray of one of three fungicides-propiconazole @ 0.1%, azoxystrobin @ 0.07%, or strobin @ 0.06%–at 50% panicle emergence stage to fungicidal control of false smut of rice.

Impact of pre-harvest application of 1-methylcyclopropene (1-MCP) on fruit quality, physiological disorders and respiration rate of ‘Scilate’ apple

The ethylene inhibitor 1-methylcyclopropene (1-MCP) is widely used in the apple industry as a post-harvest fumigation application to slow down the ripening process and maintain fruit quality during storage. With the development of a sprayable formulation (Harvista™, Agrofresh Inc, USA), it is becoming increasingly common in the apple industry to apply 1-MCP as a pre-harvest spray. This study investigated the impact of pre-harvest 1-MCP applied 1 week prior to harvest as a foliar application at 11.4 L ha−1 in 1000 L water, on the quality and respiration rate of ‘Scilate’ apples grown in the Huon Valley, Southern Tasmania, Australia. Two trials were undertaken, trial 1 examined fruit quality, flesh browning (FB) and fruit softening in 1-MCP treated and untreated fruit while trial 2 compared the respiration rate of 1-MCP treated and untreated fruit. Despite no effect on fresh fruit quality attributes, pre-harvest spray application of 1-MCP influenced post-harvest fruit quality, storability, and respiration rate of apples. Fruit treated with 1-MCP showed higher malic acid concentration (1.2 g L−1 vs 0.9 g L−1) and lower juice pH (4.6 vs 4.9) even after 7.5 months of regular air cold-storage along with a six-fold reduction in fruit softening in comparison to untreated fruit (2% vs 13%). Pre-harvest treatment of 1-MCP reduced respiration rate by 32%, and incidence of CO2 injury by over 40%. The incidence of radial type (senescent related) FB was reduced by 100%. A significant proportion of treated apples still suffered from severe CO2 injury. This study has demonstrated that pre-harvest application of 1-MCP to ‘Scilate’ fruit can be useful in maintaining long-term fruit quality during storage, reducing respiration rate, and lowering the incidence of FB in general. However, the risk of severe CO2 injury remains, especially with larger fruit harvested from trees with lighter crop loads.

Evaluation of three irrigation application systems for watermelon production in the Texas High Plains

AbstractAbout 90% of the Texas High Plains area depends on the water supply from the Ogallala aquifer. The decline of the Ogallala water table raises a concern for the sustainability of producing the traditional irrigated field crops due to their high water demand. Thus, diversifying cropping systems may be a solution. However, about 70% of the irrigated cropland uses center pivots that may negatively impact specialty crop quality. Thus, a 3‐year experiment was conducted to assess the potential of using mobile drip irrigation (MDI) to produce fresh watermelon compared to center pivot sprinkler irrigation using low‐elevation spray application (LESA), and surface drip irrigation with plastic mulch (DI). The study evaluated the effects of irrigation systems on crop yield, fruit quality, physiological responses, water use efficiency (WUE), and irrigation use efficiency (IUE). On average, plants under MDI had higher yields (106 Mg ha−1) than those under DI (70 Mg ha−1) and LESA (68 Mg ha−1). Plants under MDI and DI also had more fruits per plant (1.9) than those under LESA (1.4). The higher yield was associated with higher biomass and photosynthetic function. In general, fruit quality was not affected by irrigation system. In addition, plants under MDI system showed a higher WUE and IUE, and less water stress than those under LESA and DI systems. Results of this study suggest that irrigating under an MDI system is a good alternative for growers in the Texas High Plains that aim to diversify their cropping system with high‐value vegetable crops such as watermelon (Citrullus lanatus).

Sclerotinia sclerotiorum on bean and potato in Sinaloa: Etiology, epidemiology and alternatives for management

White mold (Sclerotinia sclerotiorum) is the main disease of bean and potato in Sinaloa. In the present review, the symptoms and signs of the disease as well as cultural and morphological characteristics of the teleomorph of the pathogen, its ecology and the epidemiology of the disease are addressed. The implementation of a prediction system which includes the carpogenic germination of the sclerotia and the phenology of both bean and potato for the management of the disease is described. This system considers soil temperature ranging from 13 to 19 °C a at depth of 2.5 cm in the soil and the flowering stage in both bean and potato to do the first spray application of synthetic fungicide to prevent the disease. In vitro studies indicated that Trichoderma harzianum, T. viride and T. atroviride reduced mycelial growth rate of S. sclerotiorum. The same antagonistic species exerted control of white mold under field conditions, where an increment of 40% of yield was observed in the treated plots, with respect to those treated with fungicide fluazinam. Future lines of research focusing on the ecology of the pathogen and management of the disease including the antagonistic fungi in the prediction system are suggested.

Fatigue and delamination of 6061 aluminum cold spray on a similar wrought substrate

Fatigue crack growth and fracture of a thick 6061 aluminum cold spray coating on 6061-T6 aluminum substrate were studied through in-situ observation of fatigue crack growth through the coating to the interface in notched four-point bend samples. Mode I cracking was observed through the coating before delamination at the substrate. Crack tip strain fields during the delamination event were plotted with DIC. Interfacial steady-state strain energy release rates were measured using the bimaterial four-point bend solutions by Charalambides. The interfacial crack primarily spread cleanly along the coating/substrate interface, with a post-fracture surface morphology containing a wavy structure with an amplitude on the same order of magnitude as the cold spray particle diameters. The in-situ video of crack propagation and coating-substrate delamination provides lessons for improving the coating-substrate interfacial toughness and thus expands use cases for structural cold spray applications

Topical larynx lidocaine Spraying reduces cardiovascular stress response caused by suspension laryngoscopic surgery

ObjectiveThis study aimed to investigate the potential reduction of cardiovascular stress response caused by suspension laryngoscopic surgery through the application of lidocaine spray on the larynx and trachea. MethodsA total of 68 patients scheduled for elective suspension laryngoscopic surgery were randomly assigned to either the lidocaine group (Group L, n = 34) or the control group (Group C, n = 33). In Group L, patients received a sprayed lidocaine dose of 2 mg/kg on the larynx and trachea after anesthesia induction, prior to intubation. In Group C, equal volumes of saline solution were administered. MAP and HR were recorded at various time points: before anesthesia (T0), 1-minute after intubation (T1), 1 and 3 min after suspension laryngoscopy (T2 and T3), at the end of the operation (T4), and at 1, 5, and 30 min after extubation (T5, T6, and T7). Arterial blood glucose, epinephrine, and norepinephrine levels were measured at T0, T2, T5, and T7. The occurrence of severe cough and sore throat at T6 and T7 after extubation was compared between the two groups. ResultsAt T0 and T1, there were no statistically significant differences in mean arterial pressures, heart rate, and blood catecholamine levels between the two groups. However, from T2 to T7, the blood pressure and heart rate in Group L were lower compared to Group C, with significant differences observed at T2‒T6 (p < 0.05). Group L also showed less elevation in blood glucose at T2, T5, and T7 (p < 0.05). The changes in epinephrine and norepinephrine levels between the two groups were statistically significant at T2 and T5 (p < 0.05). ConclusionsAdministering lidocaine spray on the larynx and trachea during intubation for suspension laryngoscopic surgery can effectively alleviate the stress response. Level 1 evidencePatients in this study are randomly assigned to the treatment or control group and are followed prospectively.

Effect of Seed Hardening and Foliar Application of Growth Substances on Morpho-biochemical Parameters of Groundnut (Arachis hypogaea L.)

Design with three replications was used for an experiment that included seed hardening as one factor with nine levels while foliar spray of Chlorocholine Chloride @500 mg/L as another factor with two levels. Leaf dry weight and stem dry were significantly maximum with GA3-150 mg/L seed hardening treatment. Meanwhile, total dry weight, protein content, oil content and anti-oxidant activity were found significantly higher in seed hardening with GA3-100 mg/L while these morphological parameters were found significantly positive result after application of foliar spray of CCC @500 mg/L as compared to control which helps to increases the quality of groundnut.

Development and evaluation of a machine vision and deep learning-based smart sprayer system for site-specific weed management in row crops: An edge computing approach

Traditional weed management often involves blanket herbicide spraying, resulting in substantial herbicide wastage, environmental concerns, and herbicide resistant issues. Smart spraying systems utilizing robotics and sensors technologies can minimize herbicide usage and provide a sustainable solution for site-specific weed management. A machine vision-based spraying system was designed and developed for weed identification and precise spray application onto the target weeds. The sprayer platform utilizes a deep learning YOLOv4 model to accurately recognize multiple weed species, facilitating targeted spray application. The platform is equipped with an FLIR RGB camera for real-time image acquisition and Nvidia Jetson AGX Orin edge device for deploying weed detection deep-learning model. The GPIO pins of Nvidia Jetson were utilized to activate relay, providing precise on/off control over the TeeJet solenoid valves for spot spraying. Both indoor and field experiments were conducted to evaluate and compare the performance of vision-based sprayer system for weed identification and precise spraying onto the target weeds. In the indoor experiment, the sprayer system showed the average effective spraying rate of 93.33 %, with the precision of 100 % and recall of 92.8 %. Conversely, the field experiment resulted in a slightly lower average effective spraying rate of 90.6 %, while maintaining a precision of 95.5 % and a recall of 89.47 %. The reduced accuracy of the spraying system in field experiment was due to varying outdoor conditions such as lighting, shadows, and wind velocity. Overall, the result of this study demonstrates the spraying system's potential for targeted herbicide application onto the grid cells containing weeds, effectively reducing herbicide usage and overall weed management costs.

Influence of Nitrogen, Potassium and Phosphorus Fertilizers with Foliar Application of Micronutrient of Iron, Zinc and Manganese on Bulb Characteristics of Single Flower Tuberose Plants (Polianthes Tuberosa, L.)

The global market for flowers and ornamental plants is expected to expand at a rate of approximately 6.3% over the next five years, reaching an estimated value of $57.4 billion USD by 2024. Tuberose (Polianthes tuberosa L.), a summer flower cultivated by small-scale growers primarily for export. The study was aimed to cultivate tuberose plants in Al-Jabal Al-Khader region, introducing them as a new cut flower crop, as a source for tuberose, and leveraging their economic potential. A field experiment was conducted over two summer growing seasons to investigate the impact of different levels of compound fertilizer (nitrogen, phosphorus and potassium, NPK 4:4:4) in application rates (0, 500, 1000, and 1500 kg.ha-1) and foliar sprays of micronutrients iron (Fe), zinc (Zn), manganese (Mn), and a )mixture of these three elements) on tuberose bulbs. The experimental design was a completely randomized block design split-plot with three replications. The NPK fertilizer levels were randomly assigned to the main plots, while the micronutrient treatments were allocated to the subplots. The study found that varying rates of NPK fertilization did not significantly affect the number of bulbs per plant over the two growing seasons. In contrast, the application of micronutrient foliar sprays had a notable impact, with the mixture of Fe, Zn, and Mn yielding the highest significant increase in bulb number per plant in both seasons. It is recommended to apply a mixture of the three micronutrients (Fe, Zn, and Mn) as fertilizer to produce high-quality Tuberose plants for various decorative purposes in landscaping.

Review and Current Status of Systena frontalis (Coleoptera: Chrysomelidae): An Insect Pest Associated with Nursery Production Systems1

Abstract Systena frontalis (F.) (Coleoptera: Chrysomelidae) is an insect pest of nursery production systems throughout the Midwest, Southeast, and Northeast regions of the United States. The original scientific name was Galleruca frontalis F. before reclassification of the genus to Systena. There is minimal information in the scientific literature providing evidence that S. frontalis is native or an introduced species. In addition, the overwintering life stage is unknown. However, records indicate that S. frontalis is native to North America based on reports of this beetle being found in 5 provinces of Canada and 31 states in the United States. Records also indicate that the adult may be the overwintering life stage. Current management strategies implemented to reduce feeding damage caused by S. frontalis adults to container-grown nursery plants are associated with foliar spray applications of contact insecticides. However, applying contact insecticides to plant material in nursery production systems is labor intensive and not cost efficient. Application of systemic insecticides to the growing medium is a management strategy that nursery producers can use to reduce feeding damage caused by S. frontalis adults. Research demonstrates that the systemic insecticides dinotefuran and thiamethoxam protect container-grown nursery plants 45 d after application. Therefore, based on empirical, scientific-based research, applying systemic insecticides before S. frontalis adults are active provides practical and cost-effective plant protection from adult feeding damage during the growing season, thereby allowing nursery producers to grow, market, and sell container-grown nursery plants.

Design and systematic evaluation of an under-canopy robotic spray system for row crops

Despite having made much improvement in sensing, automation, and control, the current broadcast spraying system has several drawbacks, such as uneven coverage, excessive chemical use, and deviation from recommended dosage. Typically, farmers use large self-propelled sprayers to spray the entire field without knowledge of spatial pest severity, potentially resulting in an unintentional application. However, application errors and the extent of chemical use can be optimized by utilizing an intelligent site-specific decision-based sprayer to control pests more efficiently. Hence, the initial project goal was to design a robotic liquid application system for row crops (e.g., sorghum and corn) and validate sprayer system performance. The critical design considerations for the spray application system were modularity; the ability to be mounted on an autonomous platform to go within 76.2-cm spaced crops; spray on either side of the crop row using spray booms; onboard hardware and software for control and data acquisition; and record as-applied data. A system with desired design requirements was built and individual sub-systems were tested under simulated lab scenarios to quantify the response time and accuracy of the spray system. The results showed that the sprayer could maintain an average system pressure within ±5% of the target under different duty cycles for each of the six nozzles. At 40% duty cycle, the nozzle pressure settling time at an error margin of ±5% from the mean was 13 ms, 20 ms, and 19 ms, for one, three, and six nozzles, respectively. Also, no substantial pressure difference was observed between nozzles installed at different heights in two different booms. Therefore, this application system could be a viable solution for autonomous platforms to site-specifically apply pesticides only on critically infested plants, has the potential to decrease the overall input costs on chemicals and reduce the negative environmental impacts.

Use of an estradiol transdermal spray in women with menopausal symptoms: a non-interventional study

Objective This study aimed to investigate the effectiveness, tolerability and application of estradiol metered-dose transdermal spray (EMDTS) in postmenopausal women during real-world use. Methods This was a prospective, non-interventional, multicenter, observational phase IV cohort study. The Menopause Rating Scale II (MRS II) was used to assess symptoms and clinical response. Safety was assessed by the occurrence of adverse events and adverse drug reactions (ADRs). Results A total of 451 postmenopausal women were enrolled at 52 gynecological practices across Germany; 383 patients were evaluated for effectiveness and 430 patients for safety. Mean age was 54.3 ± 7.4 years. In total, 228 patients (59.5%) received EMDTS monotherapy and 155 patients (40.5%) received EMDTS plus progestogens. Significant improvements (p < 0.0001) from baseline in symptom severity were recorded for all 11 items of the MRS II at 3, 6 and 12 months of treatment. At 12 months, 81.4% of patients reported improvement in hot flushes/sweating. At final visit, 73% of patients and 77% of physicians were ‘satisfied/very pleased’ with EMDTS. Most common ADRs were headache (n = 6), nausea (n = 4), dizziness (n = 4) and pruritus (n = 3). Conclusions EMDTS is an effective, well tolerated and easily applied hormone replacement therapy for women experiencing postmenopausal symptoms.

Impact of Seed Hardening and Foliar Application of Growth Substances on Morphological Parameters of Groundnut (Arachis hypogaea L.)

An experiment was carried out during summer and kharif, 2022. A Factorial Randomized Block Design with three replications was used for an experiment that included seed hardening as one factor with nine levels while foliar spray of Chlorocholine Chloride @500 mg/L as another factor with two levels. Different morphological parameters were analyzed for the experiment at different time durations like 30, 50, 70, 90 DAS and at harvest. Days to initiation of flowering, days to 50% flowering, days to maturity were significantly minimum with GA3-150 mg/L seed hardening treatment. Meanwhile, plant height, number of primary branches per plant were also found significantly higher in seed hardening with GA3-150 mg/L while all these morphological parameters were found significantly lower after application of foliar spray of CCC @500 mg/L as compared to control. Thus seed hardening with GA3-150 mg/L and foliar application of CCC @500 mg/L is suitable for enhancing the yield of groundnut.

Effect of calcium propionate dip and spray applications on botrytis blight of ornamental plants

The use of conventional fungicides to control botrytis blight of ornamentals caused by Botrytis cinerea has its limitations due to increasing resistance to site-specific fungicides. Calcium propionate (CaP) has suppressive action against this disease and resistance in B. cinerea to CaP has not been reported. This study evaluated the efficacy of postharvest dip applications of 0.1% CaP (pH 6.0) to control botrytis blight in four cut rose (Rosa ×hybrida) cultivars and analyzed gene expression of CaP-treated rose petals. CaP reduced botrytis blight symptoms in rose ‘Alive’ but not in ‘Freedom’, ‘Momentum’, and ‘Orange Crush’, and no change in gene expression in ‘Orange Crush’ was detected following CaP treatment. Aerial spray applications at 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% CaP made twice a week for 5 weeks caused minimal phytotoxicity damage to calendula (Calendula officinalis), carnation (Dianthus sp), dahlia (Dahlia sp), pansy (Viola ×wittrockiana), and snapdragon (Antirrhinum majus) leaves; however, CaP spray applications generated residues at all CaP concentrations in all species except for dahlia where no residue was observed. The results suggest that CaP will suppress botrytis blight in some but not all rose cultivars and establish a reference for phytotoxicity symptoms and visible CaP residues on ornamental plants.

Application of seaweed liquid extract improves the growth, yield, and chemical constituents of lemongrass

The rapid increase in the adoption of seaweed-based bioproducts in crop production systems can be attributed to their unique bioactive components and significant beneficial effects. In the growing interest of sustainable agricultural practices, the present study aims to reduce the dependency on chemical fertilizers while enhancing crop productivity and quality through seaweed extract. A field experiment was carried out during 2018-2019 and 2019-2020 at CSIR-CIMAP, Allalasandra, Research Center, Bengaluru to study the influence of seaweed liquid extracts as a foliar application on growth, yield, and chemical composition of lemongrass. Results revealed that the growth, herb and essential oil yield of lemongrass was improved significantly by the application of Kappaphycus alvarezii (K sap) at 20% concentration, recording herb and oil yield of 35.86 t ha−1 year−1 and 466.70 kg ha−1 year−1, respectively when conjugated with a recommended dose of fertilizer (RDF), compared to RDF alone, 30.40% and 35.70% in herb and oil yields, respectively, were recorded in this treatment. Notably, the treatment 50% RDF + K sap applied at 7.5% concentration was statistically at par with RDF with respect to the herb as well as oil yield connoting considerable scope of reducing chemical fertilizer requirement for the lemongrass. The functional relationship between herb and oil yield of lemongrass with different concentrations of seaweed sap applied at different crop stages was found to be strongly correlated (r2=0.99 and r2=0.98, respectively). Higher amounts of citronellal (0.70%) Borneol (1.10%), α-Terpineol (1.90%), and Citronellyl acetate (0.4%) were recorded in 20% K sap spray with RDF. The study revealed that the application of marine alga Kappaphycus alvarezii foliar spray above the 10 - 20% concentration significantly increased the herb, essential oil yield, and chemical constituents of lemongrass.

Effect of Potassium Schoenite (Mahalaabh) on Growth and Yield of Castor, Cotton and Groundnut

The need for precise nutrient application has become crucial in agriculture due to climate change and intensive farming practices. Deficiencies in potassium, magnesium and sulphur are critical for enhancing both crop yield and quality. Additionally, agrochemical residues in soil, water and farm products pose significant challenges. Mahalaabh (K2SO4·MgSO4·6H2O), a combination of potassium, sulphur and magnesium, offers a balanced solution to address these issues. Field experiments were conducted during the Kharif season of 2023-24 at Agrocel Industries Pvt. Ltd., Kachchh, to evaluate the impact of Mahalaabh on castor, cotton and groundnut crops. The trials were executed in a Randomized Block Design, testing different doses of Mahalaabh powder through foliar spray, fertigation and granular soil application. The results demonstrated that Mahalaabh powder is effective in enhancing productivity across the tested crops. In castor, higher doses of 10 kg/acre through drip irrigation and 20g/L foliar application increased productivity by 22.3% and 14.3% over the recommended fertilizer dose (RFD), respectively. However, in cotton, lower doses of 6kg/acre through drip irrigation and 10g/L through foliar application were more effective, resulting in 3.8% and 5.3% yield enhancements compared to RFD. In groundnut, foliar spray at 15 g/L applied thrice at 30-35, 50-55, and 70-75 days after sowing (DAS) was effective, resulting in a 22.9% higher pod yield compared to RFD. These findings highlight the importance of balanced nutrient management practices tailored to specific crop requirements for achieving optimal agricultural productivity.