Foliar Application Methods Research Articles

Management of Leaf Blight and Node Blight Diseases Indian Barnyard Millet (Echinochloa frumentacea (Roxb)

A study on the management of important diseases of rainfed kuthiraivali was carried out through biological control and fungicides in combination with seed treatment and foliar application methods and different intervals of diseases incidence. The leaf blight pathogen was isolated from the affected leaf; the isolated fungus's dark grayish-colored, fluffy mycelia were observed on the PDA medium. The mycelium was grey to olivaceous green, profusely branched, and septate. Conidiophores were single or in small groups, straight to flexuous, septate, smooth, and dark brown. Measuring 3.5 µm x 0.865 µm (1 µm), The disease incidence was observed at 15-day intervals using the percent disease index. Among three years, the seed treatment (10gm/kg) of Pseudomonas fluorescens (TNAU Pf1) followed by foliar application of Carbendazim + Mancozeb 2 gm/lit decreases the leaf blight diseases (63.63% reduction over control) and also recorded an increased yield of 1075 kg/ha of kuthiraivali. Seed treatment with Pseudomonas fluorescens Pf1 combined with foliar fungicide sprays significantly enhances yield and cost-benefit ratio under rainfed conditions while effectively managing seed-borne and foliar diseases.

Bacterial endophyte Pseudomonas mosselii PR5 improves growth, nutrient accumulation, and yield of rice (Oryza sativa L.) through various application methods

BackgroundPseudomonas spp. have drawn considerable attention due to their rhizospheric abundance and exceptional plant growth-promoting attributes. However, more research is needed on the optimal application methods of Pseudomonas mosselii for rice growth, nutrient accumulation, and yield improvement. This research explored the application of the endophytic bacterium P. mosselii PR5 on rice cultivar BRRI dhan29 with four treatments: control, seedling priming, root drenching, and bacterial cell-free culture (CFC) foliar application.ResultsPR5 led to better rice growth, improved nutrient acquisition, and higher yields compared to the control, regardless of the application method used. The highest results in fresh weight of root (146.93 g/pot), shoot (758.98 g/pot), and flag leaf (7.88 g/pot), dry weight of root (42.16 g/pot), shoot (97.32 g/pot), and flag leaf (2.69 g/pot), and grains/panicle (224.67), were obtained from seedling priming treatment, whereas root drenching resulted in maximum plant height (105.67 cm), root length (49.0 cm), tillers/pot (23.7), and panicles/pot (17.67). In all three application methods, rice grain yield per pot was higher in PR5 inoculated treatments, compared to the control. The amount of P, Mg and Zn in the shoot and N, P, Ca, Mg and Si content in the flag leaf was significantly increased along with effective suppression of naturally occurring blast disease in bacterial CFC foliar application, validated by multivariate analysis.ConclusionOur results indicated that rice seedlings priming with PR5 improved rice growth, yield and nutrient uptake, whereas CFC foliar application significantly increased the concentration of most nutrients in the rice plant and suppressed the naturally occurring rice blast disease. This research highlights the significant potential of P. mosselii PR5 in enhancing rice growth, yield, and nutrient uptake, particularly through seedling priming and CFC foliar application methods.

Bio-fortification with selenium (Se) improves quality and nutrient profile in citrus fruit

Selenium (Se) is an essential nutrient for the human body. Humans can enhance Se absorption by consuming horticultural plants, particularly fruits. Therefore, there is need for Se biofortification in fruits to meet the human demand for Se. The objective of this study was to determine the optimal Se application rate, application stage and method, and to assess their impacts on improving both the quality and nutrient profile of a sweet orange cultivar 'Hongjiangcheng' (Citrus sinensis (L.) Osbeck). 'Hongjiangcheng’ is a notable variety of mandarin orange, acclaimed for its large size, thin and smooth skin, orange-red flesh, tender and juicy texture, balanced sweetness and acidityand distinctive flavor. A field experiment was conducted at the Qiaotou Town Test Base in Chengmai County, Hainan Province, China. Biofortification of Se was done through foliar and soil application methods. Treatments were: Control (C) with no application of Se, foliar application of 25 (SeF1), 50 (SeF2), 100 (SeF3) and 200 (SeF4) mg/L and soil application of 100 mg/L (SeS1) as well as a combination of 100 mg/L Se in soil along with 50 mg/L Se on leaves (SeS1F2). At start of the experiment, 189 healthy, four-year-old citrus trees of similar size and normal growth were selected. The trees were divided into three groups of 63 each. Each group received the aforementioned treatments at the young fruit, expanding fruit and premature fruit stages. The Se was applied once during each stage before 9:00 am on sunny days. Treatments were arranged in a randomized complete block design with 9 biological replicates (7 treatments × 9 replicates = 63 citrus trees/ application stage). Foliar application of Se at rate of 200 mg/L (SeF4) enhanced total Se content in leaves by 105, 34 and 69 % at young fruit, expanding fruit and premature fruit stages compared to control (p≤0.05). Respective increments in fruits were 264, 22 and 21 %. The total Se content in leaves were 32 and 40 % higher in the SeF4 (foliar) compared to SeS1 and SeS1F2 (soil) treatments across all development stages (p≤0.05), respectively. The respective increments in fruits total Se content were 16 and 52 %. Only at the young fruit stage, the organic Se content in fruits was significantly higher in the SeF4 compared to soil application treatments (p≤0.05). Single fruit weight was enhanced by 16.61, 13.69 and 4.36 g by foliar than soil application at young fruit, expanding fruit and premature fruit stages, respectively. It was significantly higher (155.53 vs. 113.13 g) after application of SeF4 treatment at young fruit stage relative to all other treatments (p≤0.05). The application of SeF4 at the young fruit stage resulted in an increased seed rate (97 %), total soluble solids (28 %) and solid-to-acid ratio (75 %), while titratable acid decreased by 26 % compared to the control. Interestingly, Se application had non-significant effects on the fruit shape index, peel rate and residue rate across all stages (p>0.05). Additionally, a positive correlation was observed between fruit Se content and several quality indices like total soluble solids, solid acid ratio, fruit shape index and fruit weight at young fruit stage (p≤0.05). It is concluded that foliar application of Se at 200 mg/L (SeF4) during young fruit stage improved citrus Se content, its fruit weight and quality indices establishing these fruits as a valuable source of Se-rich food for human consumption.

Sugarcane Response to Two Different Application Methods of Nano-Iron and Nano-Zinc

AbstractThere are many publications over the past 20 years comparing nano-nutrients with their traditional forms. Differently, this study examined the effect of applying nano-Fe and nano-Zn—in two different ways (foliar and soil application)—on sugarcane development, yield, and mineral status using a greenhouse experiment at the National Research Centre. The study results of first yield (plant cane crop) showed that nano-Fe caused an increase in plant height, number of leaves, fresh weight (FW) of leaves, FW of stalk, and total FW by 5.3%, 20.3%, 38.0%, 27.4%, and 33.3%, respectively, compared to nano-Zn. Despite the majority of growth metrics showed to be improved by using either of the two nano-sources, both nano-Fe and nano-Zn have been demonstrated to negatively impact nutrient ratios. The foliar application method was found to be superior, and the second application of nano-Zn to soil effectively halted the growth of all treated replicates. The data of the first ratoon (second yield) showed that FW of leaves, FW of stalk, total FW, and dried weight (DW) of stalk followed one trend line (nano-Fe–soil > control-foliar (sprayed distilled water) > nano-Zn-foliar > nano-Fe-foliar > control-soil (distilled water added to soil)). In conclusion it can be noticed that using nanoparticles as a fertilizer could be a weapon with double-edges, since this may induce unexpected harmful effects. It is recommended to conduct additional research to comprehend the mechanisms underlying why a nano-source that benefits plants may harm them after the second addition.

Effect of ZnO Nanoparticles enhanced compost with different application methods on nutrient uptake and Grain Yield of Rice (Oryza sativa) Var. Inpari 32

A pot experiment using a randomized block design was conducted to test the effect of ZnO-nanoparticles enhanced compost (ZnONEC) with different application methods on nutrient uptake and grain yield of rice var. Inpari 32. The treatment tested was ZnO-NEC with various concentrations (50, 100 and 150 mg.kg-1) with direct soil and foliar application methods compared with control and inorganic fertilizer treatments. All treatments using ZnO-NEC fertilizer received 50% of the recommended dose of chemical fertilizer. The results showed that the application of ZnO-NEC 100-150 mg.kg-1 with foliar application had leaf greenness levels (SPAD Value) and N uptake that were the same as the use of inorganic fertilizer and significantly increased the uptake of P, K and Zn compared to the use of inorganic fertilizer. The ZnO-NEC 50 mg.kg-1 with direct soil application ZnO-NEC 100 and 150 mg.kg-1 with foliar application had the same high grain yield per hill as the inorganic treatment. These treatments had an average percentage of empty grains (9.14%) and grain moisture content of 27.10%, which was lower compared to the control and inorganic treatments. These findings provide new insight into the potential for using the technology of ZnO-nanoparticles enhanced compost to reduce the use of chemical fertilizers.

Effects of Organic tea concentration and application methods on growth and yield of Greenhouse Cucumber (Cucumis sativum L.) in Owo, South-western Nigeria

Organic tea (mixture of Organic Manure Extract and Spent Bleaching Extract) is used as nutrient complements in agriculture and horticulture to increase plant growth and yield. In this study a 2 X 4 factorial experiment used CRD (Completely Randomized Design) to examined the effect of compost tea herein referred to as OT [organic tea (extract made from SBE and composted manure extract (OM)] as bio-stimulants at four different concentrations (0, 20, 30, and 40 %) on the growth and fruit yield in cucumber (Cucumis sativum L.) under greenhouse condition using foliar (FO) and drip irrigation (DR) application methods. Vegetative parameters (vine length, number of branches, number of leaf per plant, leaf area, and stem girth) were studied at 50% flowering stage and yield parameters (Date to flower initiation, No of male flower, No of female flower, male/female flower ratio, number of fruit/plant, fruit length, fruit diameter, fruit weight/plant) and yield / hectare, at harvest. From the experiment organic tea application via folia method exhibited enhanced vegetative growth while application via drip irrigation was found to be more effective in influencing the yield parameters significantly. Plants that received 20% OT showed variability, but were not significantly different from control plants (0%). Similarly, plants treated with 40% OT extract showed enhanced vegetative growth and fruit yield with good quality, but high diseases infection. This study therefore provides important information on the utilization of OT and application method for increased cucumber production in the study area.

Soil and foliar zinc application techniques influence the productivity, zinc concentration, and protein content in the grains of bread wheat varieties

Micronutrient zinc (Zn) is crucial for both humans and plants. To improve the micronutrient concentration in the grains of food crops, biofortification has already been established as one of the best approaches across the globe. The current study was carried out to assess Zn enrichment in a few common wheat varieties using different Zn delivery techniques. The following treatments were applied: T<sub>1</sub>: control (without Zn), T<sub>2</sub>: Soil application of 4 kg Zn ha-1 at final land preparation, T<sub>3</sub>: Foliar application of a 0.5% Zn solution (ZnSO<sub>4</sub> x7H<sub>2</sub>O) at both tillering and booting stages, and T<sub>4</sub>: soil application of 2 kg Zn ha-1 at final land preparation + foliar application of a 0.2% Zn solution (ZnSO<sub>4</sub> x7H<sub>2</sub>O) at both tillering and booting stages. All treatments were arranged in a split-plot design and repeated three times The findings of the study revealed that the various Zn application techniques had an impact on the Zn concentration in grains significantly, ranging from 23.9 to 32.2 µg g-1 across the varieties, with an average of 28.2 µg g-1 in the control. Among these various application techniques, the soil + foliar application induced the highest response of the Zn concentration in the grains ranging from 33.7 to 37.60 µg g-1. The average protein content (%) in the grains of all wheat varieties varied by 1.21, 1.47, and 1.51%, respectively, as a result of the use of the different Zn application methods. Considering the Zn-use efficiency (%), the most Zn-efficient wheat variety was BARI Gom 28, followed by BARI Gom 26, Binagom-1, BARI Gom 25, and BARI Gom 29. In the case of grain yield, wheat variety BARI Gom 26 (4.15 t ha-1) performed the best in the soil + foliar Zn application. The soil + foliar application method outperformed the other application techniques regarding the Zn concentration, yield, and protein content in the grain.

Evaluation of different insecticides and application methods for control of Diloboderus abderus

Diloboderus abderus (Coleoptera: Melolonthidae), commonly known as "isoca", is an insect that lives in the natural field, fulfilling the function of recycling nutrients. It is an important soil pest for crops such as corn, wheat, oats and natural and cultivated grasses in countries such as Argentina, Paraguay, Uruguay and southern Brazil. In the last five years, Montes del Plata has recorded significant losses in young plantations associated with soils with a history of farms, mainly in the southwest region of the country. This damage is associated with the larval phase of the isoca, which develops in the A horizon of the soil, feeding on the roots of the recently planted eucalyptus seedlings, which can cause the death of the tree. For this reason, the objective of this work was to evaluate the control effectiveness of three active ingredients (Imidacloprid, Acetamiprid and Thiamethoxan), and the best application method (foliar, surface application to the soil and root immersion) that would allow protecting the plants in their critical stage. The evaluation was carried out on Eucalyptus plants in pots where three stage-three isocas larvae were placed. After 30 days, the plants were dug up and plant survival, root damage, and larval mortality were evaluated. The results indicated that the three active ingredients were efficient in control, with survival rates of isoca of less than 30%. Thiamethoxan was the most efficient with 100% control of isocas, regardless of the application method. The foliar application method showed the best results with isocas survival rates of less than 15%, regardless of the active ingredient applied. Although it is necessary to continue the research by evaluating different site conditions, application times and doses of active ingredients, the results achieved indicate that the application of Thiamethoxan on the plantation line is the profitable alternative to mitigate losses.

Optimization of castor bean (Ricinus communis L.) cultivation methods using biostimulants in an arid climate

In arid areas, low soil fertility, an imbalance of nutrients, and the inability of crops to absorb some nutrients are among the main constraints on crop production. The use of biological fertilizers and biostimulants can be a suitable solution. A 2-year field experiment was conducted as a factorial experiment based on a randomized complete block design with three replications to study the response of castor bean to arbuscular mycorrhizal fungi (AMF) and amino acid biostimulant (AAB) (foliar, soil, and combined application methods). Findings showed that plants inoculated with AMF had better performance: the biological and seed yields were increased by an average of 20.9 and 26.4% over the 2 years of the experiment. The yield components showed a 14.0 to 18.6% increase, and the water productivity (WP) was improved by 13.9%. The seed oil content was increased by 5.1%: linoleic acid, an oil fatty acid, showed the highest response, with an increase of 10.0%. Among the AAB treatments, the combined application method (CAM) brought the best results. The highest increases in biological and seed yields (68.4 and 63.2%, respectively) were obtained from the CAM treatment. The WP was improved by 67.8% and the seed oil content showed an increase of 9.4%. Among the fatty acids, the highest increase (24.4%) belonged to linoleic acid. The results show a positive and significant response of castor beans to biostimulants, which indicates that replacing chemicals with biological fertilizers could be a promising approach to the cultivation of castor beans in arid climates.

Soybean (Glycine max L.) Yield and Yield Component Under Different Planting Time and Foliar Application of Humic Acid

A triplicate field experiment laid out in randomized complete block design was conducted to evaluate the effect of foliar application of humic acid rates (HAR) at Bakrajo, Sulaimani which is (located at 35°32'52.8"N and 45°21'16.6"E) belongs to Kurdistan region of Iraq with the silty clay soil type. Five different Humic Acid rates (HAR) which were (0 (control), 2,4,6,8 g/L) and two cultivation period (CP) which were cultivation Period 1 (CP1) on 15 May 2022 and cultivation Period 2 (CP2) on 1st of June 2022. The effect of foliar Humic acid rates application methods was highly significant on the Pod No./ Plant, Empty Pod/Plant, Seed Weight / Plant (g) and yield (kg/ha) and significant on the 1000 Seed Weight (g). While, the effect of cultivation period (CP) was highly significant only for the Pod No./ Plant and the insignificantly affected the other parameters including Empty Pod/Plant, Seed No./ Pod, 1000 Seed Weight (g), Weight / Plant (g) and yield (kg/ha). The maximum Pod No./ Plant, Empty Pod/Plant, Seed Weight / Plant (g) and yield (kg/ha) and significant on the 1000 Seed Weight (g) were observed under foliar application of HAR of 6 g/L and the best cultivation period for sowing humic acid was (CP1) which was on 15 May.

Investigating the impact of TiO2 nanoparticles on bioactive compounds in sweet pepper seedlings: a comparison of foliar and root application methods

Engineered TiO2 nanoparticles (TiO2-NPs) are broadly produced and utilized in various consumer products. However, plant uptake of NPs may lead to disruptions in physiological and metabolic processes, particularly when the plant’s defense mechanisms are overwhelmed. In this study, sweet pepper seedlings were exposed to TiO2-NPs via foliar (2.5% suspension) and root (0.5% suspension) methods, with plants treated with distilled water serving as controls. Results showed that foliar application caused higher accumulation of Ti in leaves as compared to stems, while root exposure led to a higher increase of Ti content in stems than in leaves. Additionally, foliar application led to alterations in chemical composition of the plants, including changes in malondialdehyde (MDA), L-ascorbic acid, total phenolics content, carotenoids, in total antioxidant capacity (TAC) and antioxidant enzymes activity. Root exposure also affected enzyme activity and TAC, but also altered H2O2, MDA and glutathione content. Chlorophylls remained at stable level in the leaves of the seedlings. Overall, these studies provide important information on plant-nanoparticle interactions and the potential effects of different nanoparticle application strategies. These data indicate also that the specific nanoparticles, applied at a controlled manner, have potential to boost the plant metabolism and improve stress tolerance, which is an important factor affecting crops’ quality and productivity.

Integrating Application Methods and Concentrations of Salicylic Acid as an Avenue to Enhance Growth, Production, and Water Use Efficiency of Wheat under Full and Deficit Irrigation in Arid Countries

As water deficit in arid countries has already become the norm rather than the exception, water conservation in crop production processes has become very critical. Therefore, it is urgent to develop feasible strategies to achieve this goal. Exogenous application of salicylic acid (SA) has been proposed as one of the effective and economical strategies for mitigating water deficit in plants. However, the recommendations concerning the proper application methods (AMs) and the optimal concentrations (Cons) of SA under field conditions seem contradictory. Here, a two-year field study was conducted to compare the effects of twelve combinations of AMs and Cons on the vegetative growth, physiological parameters, yield, and irrigation water use efficiency (IWUE) of wheat under full (FL) and limited (LM) irrigation regimes. These combinations included seed soaking in purified water (S0), 0.5 mM SA (S1), and 1.0 mM SA (S2); foliar spray of SA at concentrations of 1.0 mM (F1), 2.0 mM (F2), and 3.0 mM (F3); and combinations of S1 and S2 with F1 (S1F1 and S2F1), F2 (S1F2 and S2F2), and F3 (S1F3 and S2F3). The results showed that the LM regime caused a significant reduction in all vegetative growth, physiological, and yield parameters, while it led to an increase in IWUE. The application of SA through seed soaking, foliar application, and a combination of both methods increased all of the studied parameters in all the evaluated times, resulting in higher values for all parameters than the treatment without SA (S0). The multivariate analyses, including principal component analysis and heatmapping, identified the foliar application method with 1-3 mM SA alone or in combination with seed soaking with 0.5 mM SA as the best treatments for the optimal performance of wheat under both irrigation regimes. Overall, our results indicated that exogenous application of SA has the potential to greatly improve growth, yield, and IWUE under limited water application, while optimal coupling combinations of AMs and Cons were required for positive effects in field conditions.

Evaluation of Roholtiella sp. Extract on Bell Pepper (Capsicum annuum L.) Yield and Quality in a Hydroponic Greenhouse System.

This study was carried out to investigate the impacts of cyanobacteria (Roholtiella sp.) high-value product extract (HVPE) and water resuspended biomass WRB treatments on bell pepper production using the hydroponic system under greenhouse conditions. Six cyanobacteria treatments (6 ml L−1, 4 ml L−1, and 2 ml L−1 – HVPE, 6 ml L−1, 4 ml L−1, and 2 ml L−1 – WRB, and TR0 as control) were evaluated using the foliar application method. The results showed that foliar application of HVPE with treatments of 2 ml L−1, 4 ml L−1, and 6 ml L−1 produced significantly higher values of physical growth parameters of bell pepper (BP) plants (shoot length, the number of leaves, plant leaf length, plant leaf width, and the diameter of the shoot), SPAD index, yield components (the fruit length, fruit width, the number of fruit per plant, and fresh weight per fruit), biochemical composition [ascorbic acid, phenolic acid, and total soluble solids (TSS)], and the total yield compared to the control group TR0. Also, significant higher values of growth parameters (shoot length, the number of leaves, plant leaf length, plant leaf width, the diameter of the shoot), SPAD index, yield components (the fruit length, fruit width, the number of fruits per plant, and fresh weight per fruit), biochemical composition [ascorbic acid, phenolic acid, and total soluble solids (TSS)], and the total yield were obtained with foliar spraying WRB at 2 ml L−1, 4 ml L−1, and 6 ml L−1 compared to the control group TR0. Consequently, the treated bell pepper with Roholtiella sp. HVPE and WRB were more efficient in enhancing production and chemical constituents compared with the control group.

Boron, Manganese, and Zinc Sorption and Leaf Uptake on Citrus Cultivated on a Sandy Soil.

Solute fate in soil-plant continuum could either be soil or leaf uptake or leaching beyond the rooting zone. An adsorption coefficient (KD) is an important chemical property to describe the interaction between the solute and soil, affecting the solute movement in soils from one point to another. Boron (B), manganese (Mn), and zinc (Zn) uptake are evident in the leaves as a constituent of photosynthesis and other plant body-building mechanisms for growth and development. This study investigates the availability of micronutrients (B, Mn, and Zn) to citrus trees through modified application methods and rates. Leaf samples were collected from experimental plots arranged in a randomized complete block design, with 4 micronutrient treatments: control, foliar ×1, foliar ×2, and soil ×1. Boron, Mn, and Zn rates were 1.12, 10.08, and 5.60 kg ha−1, respectively. Composite soil samples were randomly collected at 5 points, and a 1-point adsorption study was conducted in 4 soil depths at an increment of 15 cm from the soil surface. Adsorption coefficient (KD) for Mn and B was 22 and 3 times higher at 0–15 cm than at soil depth of 15–60 cm. The adsorption coefficient (KD) for Zn was 2.5 times greater at 0–15 cm than 15–30 cm soil depth, while there was little or no sorption at 30–60 cm. Leaf Mn and Zn concentrations showed that foliar spray was 2 times higher than the soil application method, while B showed that the soil application method was 2 times higher than foliar application method for 2 seasons sampling events. Thus, the behavior of B, Mn, and Zn in the soil via adsorption coefficient (KD) reflects the availability of B, Mn, and Zn in the citrus leaves.

Influence of Manganese on Nutrient Uptake in Rice Plants under Saline Conditions

Salinity-induced nutritional disorders adversely affect the performance of crops. The consequence of salinity disorders may result on nutrient availability, competitive uptake, transport or partitioning within the plants. Present study was aimed to investigate the effects of Mn application on nutrient uptake contributing to the salinity tolerance of the rice. A hydroponic experiment was carried out in National Agriculture Research Centre, Islamabad, Pakistan, on two rice varieties. Three NaCl salt concentrations, namely 0, 25, 50 mmol were used. Manganese sulphate was used for foliar and root application with four concentrations (0, 2, 4, 8 mg Mn L-1). Salinity decreased the uptake of P, K, Ca, Mg, Mn and Zn in both applications methods while application of Mn increased the uptake of almost all the investigated macro and micronutrients. Root applications of Mn and foliar application methods were compared where root application method was found better for most of the nutrient uptake. Interaction effect i.e salinity × Mn treatment × methods of application was significant. The results showed that Mn application can improve the nutrient uptake capability contributing to the salinity tolerance in rice.

Effects of micronutrients on growth and yield of potato

A field experiment was carried out at the Horticulture Farm of the Bangladesh Agricultural University, Mymensingh to evaluate the effects of micronutrients and their methods of application on growth and yield of potato cv. Diamant during the period from November 2019 to March 2020. The experiment consisted of two factors, Factor A: Two methods of micronutrient application viz., M1= Basal and M2= Foliar, and Factor B: Four levels of micronutrients viz., T0= control treatment, T1= Boron (B) @ 2 kg/ha, T2= Zinc (Zn) @ 3 kg/ha, T3= B @ 2 kg/ha + Zn @ 3 kg/ha. The experiment was laid out in split plot design with three replications. Result of the experiment revealed that application method and different levels of micronutrients alone or in combination significantly influenced all the parameters studied. The highest tuber yield (3.53 t/ha) was obtained with foliar application and the lowest was found from basal application. On the other hand the highest tuber yield (4.56 t/ha) was obtained when B + Zn @ 2 kg B/ha + 3 kg Zn/ha was applied and the lowest was recorded from control treatment. Among the treatment combinations, foliar application of micronutrients along with combined treatment of B + Zn @ 2 kg/ha + 3 kg/ha produced the maximum tuber yield (4.89 t/ha) while the lowest was obtained from the control treatment. Therefore, foliar application method along with the combined treatment of boron plus zinc was found to be better in respect of growth and yield of potato.

Green Synthesized Metal Oxide Nanoparticles Mediate Growth Regulation and Physiology of Crop Plants under Drought Stress.

Metal oxide nanoparticles (MONPs) are regarded as critical tools for overcoming ongoing and prospective crop productivity challenges. MONPs with distinct physiochemical characteristics boost crop production and resistance to abiotic stresses such as drought. They have recently been used to improve plant growth, physiology, and yield of a variety of crops grown in drought-stressed settings. Additionally, they mitigate drought-induced reactive oxygen species (ROS) through the aggregation of osmolytes, which results in enhanced osmotic adaptation and crop water balance. These roles of MONPs are based on their physicochemical and biological features, foliar application method, and the applied MONPs concentrations. In this review, we focused on three important metal oxide nanoparticles that are widely used in agriculture: titanium dioxide (TiO2), zinc oxide (ZnO), and iron oxide (Fe3O4). The impacts of various MONPs forms, features, and dosages on plant growth and development under drought stress are summarized and discussed. Overall, this review will contribute to our present understanding of MONPs’ effects on plants in alleviating drought stress in crop plants.

Influence of elicitor molecules on chlorophyll content in groundnut plants challenged with stem rot pathogen (Sclerotium rolfsii) under greenhouse conditions

Groundnut is an important edible oil crop plant whose quality and yield are greatly affected by biotic and abiotic stress. The process ofmechanisms ofrecovery fromstress are also critical to its productivity, but are currently poorly characterized. The present investigation was carried out to understand the ability of different elicitors (piperine, reserpine and b-sitosterol) to induce resistance against stress in groundnut. The chlorophyll content in groundnut leaves was measured using SPAD chlorophyll meter following the seed treatment, foliar application and micro-injection of phytochemicals. The SCMR (SPAD chlorophyll meter reading) of phytochemical-treated plants was found to be more in comparison with the untreated plants. All the three phytochemicals were found to be effective in increasing the chlorophyll content in groundnut leaves. MaximumSCMR (42.14) was observed in plants treated with piperine through foliar application method.

Effects of hydrogen peroxide application on agronomic traits of rice (Oryza sativa L.) under drought stress

Drought stress is a major environmental factor limiting crop growth and productivity. Hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) plays an essential role during stress response by acting as a signal molecule that activates multiple stress tolerance mechanisms. In this study, the effects of H<sub>2</sub>O<sub>2</sub> on agronomic traits were studied in rice (Oryza sativa L.) cv. Khao Dawk Mali 105 (KDML 105) was subjected to drought stress. H<sub>2</sub>O<sub>2</sub> was applied by either seed priming or foliar application method with a concentration of 1, 5, and 15 mmol/L. The results showed that both seed priming and foliar application with H<sub>2</sub>O<sub>2</sub> improved some yield components. The tiller numbers, number of panicles, number of filled grains, filled grain weight, and harvest index were improved approximately 1.13, 1.04, 1.23, 1.21, and 1.1 times compared to the untreated plants. Foliar application, however, helps the plant by reducing yield loss as indicated by a 0.5-time reduction in the number of unfilled grain and lower unfilled grain weight. It was suggested that 5 mmol/L H<sub>2</sub>O<sub>2</sub> was the most effective concentration to alleviate the effect of drought stress during the reproductive stage in rice.

Effect of boron on the yield of wheat (Triticum aestivum L.) under center pivot sprinkler irrigation system in the West Desert of Iraq

Two field experiments were conducted under field conditions under a sprinkler irrigation system in the West desert of Iraq, Al-Qaim Area, 400 km west of Baghdad. Underground water was used as a source of irrigation water to study the effect of different rates and different times of boron application on wheat cv. Ibaa99. RCBD with five treatments and three replications was used in this study. Boron dose was 2 kg/ha for soil application method and 0.30 kg/ha for foliar application method. Boron treatments were: 0 (control T1), 2 kg B ha-1 at sowing time (T2), 2 kg B ha-1 at 30 days after sowing (T3), 0.3 kg B ha-1 foliar application at 60 days after sowing (T4) and 0.3 kg B ha-1 for foliar application at 90 days after sowing (T5). Most boron treatments gave a significant increase as compared with control in morphological, physiological and productivity characters of wheat crop. The results revealed that B application treatment at 30 days after sowing time increased significantly the 1000 grains weight (17.6%) while T5 treatment increased significantly the chlorophyll content (12.41%) over control. In most cases, B application treatment at 60 days after sowing time showed the best results and increased significantly the plant height (5.24%), leaf area (9.18%), number of grains spike-1 (30.9 %), number of spike m-2 (18.8%), spike length (65.6%), Grains yield (34.6%) over control. There was evidence that the best dose of boron was 0.3 kg B ha-1 and the best time of B application to the foliage was at 60 days after sowing.