Foliar Application Of Nitrogen Research Articles

Enhancing the productivity and nutritional quality of lentil (Lens culinaris L.) with combined foliar application of zinc and urea

There is need to enhance the nutritional quality of lentil for ameliorating nutrient deficiencies in people especially vegetarians. The study was carried out to investigate the effect of soil application of zinc (Zn) and foliar application of Zn and nitrogen [(N) through urea] on grain yield and enrichment of grain with Zn in lentil. The field experiments were conducted at two locations Ludhiana and Faridkot, India. The experiment was consisted of eleven treatments (control, soil application of 25 kg ha−1 ZnSO4 at sowing time, foliar spray of sole 0.5% ZnSO4 or 2% urea and combined foliar spray of 0.5% ZnSO4 + 2% urea at flowering, pod formation, and flowering + pod formation stages). The foliar application of 0.5% ZnSO4 + 2% urea spray at flowering + pod formation stages significantly improved the grain yield, Zn and iron (Fe) concentration at maturity in stover and grain (whole as well as split) of lentil and protein content in stover and grain. The combined application of ZnSO4 (0.5%) + urea (2%) at flowering + pod formation stages can be done to improve not only the grain yield (on an average 29.5%) but also the Zn (49.7%) and Fe (17.4%) concentration in lentil grain, which, can help in ameliorating malnutrition in human population.

Influence of Foliar Application of Nitrogen through Urea and Nano Urea on Morphophysiological and Yield in Foxtail Millet (Setaria italica L.)

A field experiment was conducted at College of Agriculture Nagpur, during Kharif 2023 in randomized blocked design (RBD) with PDKV Yashshree (BFTM-82) variety, at Research Farm of Agricultural Botany Section, College of Agriculture Nagpur, with three replications and eight treatments. The results revealed that the best treatment 25 N kg ha-1 + two spray of nano urea @ 4 ml L-1 (T8) applied at tillering and pre-flowering stage was significantly superior as compared to other treatments which shows the highest value in morpho-physiological viz., Plant height (163.00 cm) at 80 DAS, days to 50% flowering (57.00), days to maturity (87.00), RGR (0.095 g-1 dm-2 day-1 ) at 60-80 DAS and CGR (0.82 g-1 cm-2 day-1) at 60-80 DAS and yield parameters viz., No. of panicle hill-1 (4.90), Panicle length (24.37 cm), No. of spikelet panicle-1 (66.07), Grain yield kg plot-1 (1.30),Grain yield kg ha-1 (1421.78),Harvest index (63.50%) of foxtail millet.

Effect of foliar application of nitrogen through urea and nano urea on biochemical and yield in foxtail millet (Setaria italica L.)

Effect of foliar application of nitrogen through urea and nano urea on biochemical and yield in foxtail millet (Setaria italica L.)

Interactive Effect of Nitrogen, Zinc (Zn) and Iron (Fe) on the Growth and yield Characteristics of Gobhi Sarson (Brassica napus L.)

Brassica napus L., commonly known as Gobhi Sarson in India, is a vital oilseed crop contributing significantly to the agricultural economy. India stands as the fourth-largest producer of oilseeds, with mustard-rapeseed, including Brassica napus, constituting about 28.6% of the total oilseed production [1]. The experiment titled "Study on Foliar Application of Nitrogen, Zinc (Zn), and Iron (Fe) on the Growth and Yield Characteristics of Gobhi Sarson (Brassica napus L.)" was conducted at the research farm of Lovely Professional University, Punjab, during the Rabi season of 2023-24. A total of nine treatments with three replications were evaluated using a Randomized Block Design. The findings indicate that Treatment 9 (75%RDF + 1% Urea + 0.5% FeSO4 + 0.5% ZnSO4) demonstrated the highest plant height, fresh weight, dry weight, leaf area, primary and secondary branches per plant, number of siliquae per plant, seeds per siliquae, 1000-seed weight, seed yield, biological yield, and oil content. Treatment 5 (50%RDF + 1% Urea + 0.5% FeSO4 + 0.5% ZnSO4) also performed well across these parameters, albeit to a slightly lesser extent. (T9) recorded the highest seed yield (19.7 q ha-1), significantly outperforming all other treatments, with Treatment 5 being statistically comparable. Moreover, Treatment 9 exhibited the maximum oil content (41.2%), followed closely by Treatment 5 with oil content of 40.6%. Conversely, the control treatment (T1) yielded the lowest oil content. These results underscore the efficacy of foliar application of 75% RDF with 1% Urea, 0.5% FeSO4, and 0.5% ZnSO4 in enhancing the growth and yield characteristics of Gobhi Sarson, with Treatment 5 showing similar trends.

THE FOLIAR APPLICATION OF NITROGEN AND ZINC APPLIED DURING TILLERING AND BOOTING STAGE ENHANCED THE GROWTH AND PRODUCTION OF WHEAT (TRITICUM AESTIVUM L.)

Foliar application of nitrogen and zinc has proven beneficial to achieve high yield and growth of wheat. A field trial was conducted with Randomized Complete Block Design (RCBD) in three replications, at Student’s Experiment Farm, Department of Agronomy, Sindh Agriculture University, Tandojam during spring 2022-2023. The study explored the effect of foliar application of nitrogen (N) and zinc (Zn) on wheat (Triticum sativum L.) variety TD-1 on different growth stages. The treatment comprised T1 = Control, T2 = 2.0% N (tillering), T3 = 2.0% N (booting), T4 = 0.1% Zn (tillering), T5 = 0.1% Zn (booting), T6 = 2.0% N + 0.1% Zn (tillering), and T7 = 2.0% N + 0.1% Zn (booting). The results revealed that all the parameters were significantly affected (p <0.05) by foliar applications of N and Zn at both tillering and booting stages. The highest growth and yield traits were recorded when the plants were treated with 2.0 % N + 0.1% Zn applied (foliar) at tillering stage. However, the plants grown under control conditions exhibited lower performance for all the traits recorded. In conclusion, the interaction of 2.0% N + 0.1% Zn with foliar spray demonstrated positive response towards wheat variety TD-1 at tillering stage as compared to other treatments. Hence, the combined strategy of applying foliar nitrogen and zinc at tillering stage is recommended to get higher grain yields and plant growth for chaff production

Influence of seed rate and foliar nitrogen on productivity and profitability of wheat (Triticum aestivum) in green manure basmati rice (Oryza sativa) wheat cropping system

A field experiment was conducted during the winter (rabi) season of 2021–22 at Punjab Agricultural University, Ludhiana to study the effect of varied seed rate and 3% foliar nitrogen application at different stages on productivity and economics of wheat (Triticum aestivum L.) green manure basmati rice (Oryza sativa L.) (T) wheat cropping. The treatments consisted of T1 recommended seed rate (100 kg/ha) with 3% foliar N application at 21 25 days after sowing (DAS), T2 (45–50 DAS) and T3 (60 65 DAS); T4 (10% reduced seed rate (90 kg/ha) with 3% foliar N application at 21 25 DAS), T5 (45 50 DAS) and T6 (60–65 DAS); T7 (20% reduced seed rate (80 kg/ha) with 3% foliar N application at 21 25 DAS), T8 (45–50 DAS), T9 (60–65 DAS) and T10 (control). The treatments were laid out in randomized block design with 3 replications. Significantly higher number of tillers (390.3 grains/pike (39.3), longer spike length (11.9 cm) were obtained from treatment T9 . Similarly, higher grain yield (5.41 t/ha), net returns (99,760/ha) and benefit cost ratio (2.33) were recorded with treatment (T9 ). Thus 20% reduced seed rate (80 kg/ha) with 3% foliar nitrogen application at 60 65 DAS claimed better management practices in achieving higher yield, yield attributes and net returns.

Effect of Different Sources of Nitrogen and Phosphorus and Application Methods on Yield and Quality of Hybrid Pearl Millet

Due to high yielding and short duration hybrid pearl millet got populized in last few years under pearlmillet-mustard/wheat cropping system but its required higher nutrient as compared to composite varieties but farmers apply only N and little amount of P which is responsile for low yield therefore, the present study was carried out during kharif 2021 and 2022 with 12 treatments of different sources which are chemical fertilizers, vermicompost (VC) and bio-fertilizers(Azotobacter and PSB) and application methods (seed treatment, soil and foliar application) of nitrogen and phosphorus in RBD with 3 replications. The resulted indicated that the application of 100% Nitrogen and Phosphorus by chemical fertilizers produced significantly higher yield attributes (length and girth of cobs) and yield parameter (grain and stover yield and harvest index) of pearlmilletas compared to 50 and 75% NP treatments. Maximum grain yield 29.87 q ha-1) was noted with integration of chemical, organic and bio fertilizers (75% NP + Seed treatment by Azoto + PSB + 5 t VCha-1) which was significantly higher over rest of all other treatments. Minimum yield parameters were noted with control (0 % NP). Application of vermicompost @ 5 t ha-1 with 75 per cent of NP and inoculation of Azotobacter and PSB improved test weight and protein content.

Effect of various doses of basal and foliar application of nitrogen and potassium with trace elements on summer groundnut (Arachis hypogaea)

The present field study was carried out during summer season of 2020 and 2021 at Jaguli Instructional Farm, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal to study the effect of solid and foliar grade of N and K along with trace elements in groundnut (Arachis hypogaea L.). The experiment was laid out in a split-plot design with 3 replications. In main plot; F0, control; F1, 50% RDN and K; F2, 75% RDN and K and; F3, 100% RDN and K and sub-plot T1, Starter dose of N and K @2% with 10:20 ratio + micronutrient mixture of Fe, B, Zn and Mo foliar spray at 30 DAE; T2, Booster dose of N and K @2% with 5:40 ratio + micronutrient mixture of Fe, B, Zn and Mo foliar spray at 45 and 60 DAE; and T3, Starter dose + Booster dose. Growth and yield attributes of groundnut were significantly influenced by application of inorganic fertilizer and maximum were recorded with 100% of RDN and K. Foliar applications of RDN and K with a micronutrient mixture responded better at later stages (45 and 60 DAE) than at an earlier stage (30 DAE). Higher groundnut pod yield was obtained with basal application of 100% of RDN and K but performed statistically same response to the treatment 75% of RDN and K. The pod yield increased by 5–12% with each incremental dose of inorganic fertilizer, while it decreased in control. Booster dose of N and K gave higher pod and oil yield to starter dose. Maximum BCR of 2.38 and 1.99 was found in 100% of RDN and K and in booster doses of N and K. Inorganic fertilizer as basal and foliar application + micronutrients increased the groundnut pod yield but foliar application was not substitute to any quantity of inorganic fertilizer.

Effect of foliar calcium and nitrogen treatments on yield and fruit quality of table grapes cv. ‘Cardinal‘

The foliar fertilization has been used as an important agrotechnical measure to avoid deficiencies and to improve quality. During the three consecutive years, a study has been performed on Vitis vinifera L. (cv. ‘Cardinal’) to examine whether a yield and grape berry quality have been affected by the foliar application of Ca and N fertilizers. A liquid mineral fertilizer containing 40% Ca(NO₃)₂ as Variant I and 31% N with 0,015 % Fe-chelate; 0,01 % Mg – chelat as Variant II (in text) has been sprayed four times during the growing period (before and after blooming, buckshot berries, and verasion). Results showed that foliar application of calcium and nitrogen increased the yield of table grapes in all three years of research, in comparison with a control variant. The highest yields of grapes in all three years of investigations were achieved in Variant II – 4.57 kg/vine (14.85 t/ha). During the tree years of investigations, the largest mass of grape bunch and berries were recorded in Variant II (382g and 368.68g), while the lowest cluster weight was in the control variant (344g and 330.92g). With a reference to the mechanical properties of the grape berries, the highest resistance to pressure (2229.70g) and breaking resistance (364.52g) were found in Variant I, treated with Ca fertilizer. The foliar application significantly affects the mechanical properties (resistance of the berry to pressure and breaking), especially in Variant I. The application of different types of foliar fertilizers did not have any significant effect on sugar contents and total acids, compared with the control variant.

A adubação foliar com nitrogênio alivia os efeitos nocivos do estresse salino no manjericão roxo

ABSTRACT Salinity can have detrimental effects on plant development. To minimize this damage, strategies such as balanced maintenance of plants’ nutritional status have been proposed previously. The objective of this study is to investigate whether the optimization of foliar nitrogen fertilization can promote the growth and photochemical efficiency of purple basil subjected to salt stress. The experiment was performed using a randomized block design with an incomplete 5 × 5 factorial arrangement generated through experimental matrix Central Composite Design with two parameters: salinity of irrigation water at 0.5, 0.81, 2.75, 4.69, and 5.50 dS m-1; and nitrogen doses at 0, 58.58, 200, 341.42, and 400 mg L-1. It was found that an increase in the salinity of irrigation water reduced the growth and photochemical efficiency of purple basil. However, the foliar application of nitrogen at the concentration of 400 mg L-1 attenuated the harmful effects of salinity on both the absolute and relative growth rates of stem diameter, the relative growth of plant height, and chlorophyll A fluorescence. These results showed that foliar nitrogen fertilization is a suitable strategy to help mitigate salt stress in basil plants.

Effect of mineral fertilizers on the taste qualities of apple varieties

This article presents the results of a 3-year research study into the effect of soil and foliar application of nitrogen and potassium fertilizers on the taste qualities of the Veniaminovskoe (Rvi6) and Sinap Orlovskii (3×) apple varieties bred at the Russian Research Institute of Fruit Crop Breeding (VNIISPK). The assumption that varietal features are the most important factor that determines taste was confirmed. In addition, the influence of weather conditions of the growing season on the chemical composition of fruits was observed. Thus, the year of 2019 was characterized by the most favorable weather conditions of the growing season. In August, during fruit ripening, the optimum temperature and humidity regime had a positive effect on the accumulation of soluble solids, sugars, and titratable acids in both varieties under study. However, the varieties responded differently to the same doses of mineral fertilizers. The application of fertilizers had no significant impact on the content of the studied components and the sugar-acid ratio in Veniaminovskoe fruits. Conversely, Sinap Orlovsky was found to be responsive to this agricultural practice. In 2019, the joint application of triple foliar and soil fertilizing using N30K40, N60K80, and N90K120 in various doses had a positive effect on the reduction of titratable acidity in fruits of this variety. As a result, the sugar-acid ratio increased by 1.3–1.9 times. Over the entire study period (2017–2019), a significant decrease in the content of sugars in Sinap Orlovsky fruits was observed in the variant with additional foliar fertilizing compared to the control. During the study period, the high doses of N90K120 nitrogen and potassium fertilizers along with foliar application contributed to a significant increase in the sugar-acid ratio in Sinap Orlovsky fruits, which significantly exceeded the control.

Effect of foliar nitrogen and sulfur applications on aroma and flavor profile of petit manseng (Vitis vinifera L.) using descriptive analysis

ABSTRACT Wine aroma and flavor profiles of petit manseng associated with various vineyard nitrogen treatments were evaluated using descriptive sensory analysis. Treatments consisted of six field replicates of (1) control with no nitrogen or sulfur applications, (2) 30 kg/ha of nitrogen (calcium nitrate) applied to soil just after flowering, (3) 15 kg/ha of nitrogen (urea) in two split foliar applications prior to véraison, and (4) 15 kg/ha of nitrogen (urea) and 5 kg/ha of sulfur (micronized sulfur) in two split foliar applications prior to véraison. Eight panelists were trained to identify and quantify a total of 24 wine aroma, flavor, texture/mouthfeel and aftertaste attributes. Analysis of variance (ANOVA) revealed significant variation in 23 of the 24 attributes used among the four treatments. Biplots of principal components analysis of wine flavor and aroma suggest that foliar N and foliar NS treatments gave more tropical flavors and aromas compared to other treatments. Sensory aspects that characterized the aroma and flavor profile of the different petit manseng wine may be correlated with chemical changes found in the fruit and wine as a result of vineyard treatment.

Infl uences of Nitrogen, Magnesium and Soil Moisture Contents and their Interactions on Yield Quality and Tolerance Indices of Rosemary (Rosmarinus offi cinalis L.)

The present study was carried out in the glasshouse of the Department of Biology, College of Science, Salahaddin University- Erbil, and laboratories of Research Center in Erbil Polytechnic University, from April 21st, 2019 to July 26th, 2020, to determine the eff ects of foliar application of nitrogen (N1:100, N2:200, and N3:300 kg. h-1) and magnesium (Mg1:0.0, Mg 2:30, and Mg3:60 kg. h-1) applied under two diff erent soil moisture contents (SM1:100% fi eld capacity (FC) and SM2: 60% FC) on some physiological properties and yield quality of rosemary plants (Rosmarinus offi cinalis L.). A factorial experiment was laid out according to a completely randomized design with four replications. Two cuttings were taken from the rosemary shoots (in March, and July, 2020). Results showed that SM2 decreased phenolic compounds in cut 1 (cut 1), dry matter percent in leaves in cut 2 and relative nitrogen yield in cut 1, cut 2 & cut 1+2. N3 increased dry matter in leaves shoots in cut2 signifi cantly, proline, phenolic compounds in leaves, stress tolerance index (STI), modifi ed stress tolerance index 1(MSTIK1), & modifi ed stress tolerance index 2 (MSTIK2). The interaction treatment SM2Mg2 increased the proline content in dry leaves. The proline content was increased by the triple interactions SM2N3Mg2 and SM2N3Mg3.

Uptake and Translocation of Foliar-Applied L-Proline in Sweet Cherry (Prunus avium L.)

Foliar application of nitrogen (N) may supplement soil-applied N in sweet cherry orchards. The proteinogenic amino acid L-proline is a potential source of organic N. However, little is understood about its uptake and effects on fruit quality. In this study, 15N-labelled L-proline was spray-applied to branches of the cultivar ‘Lapins’ either pre- or post-harvest. Leaves, fruit, and whole branches were sampled to investigate the uptake and allocation of foliar-applied N. Both treatments resulted in elevated 15N levels in leaves, with N derived from proline (%NDP) comprising 0.22% and 0.45% after pre- and post-harvest applications, respectively. The fruit was a sink for pre-harvest L-proline, with the highest %NDP in the pedicel (0.21%), followed by the skin (0.17%) and flesh (0.12%). Quality outcomes of smaller, darker fruit with lower stem retention indicate advanced maturity following L-proline application. Both pre- and post-harvest treatments resulted in the recovery of 15N in branches at late dormancy, with %NDP in bark (0.12%), buds (0.15%), and wood (0.02%) of the post-harvest treatment twice as high compared with those from the pre-harvest treatment. This study demonstrates proof of concept of the uptake of L-proline into the leaves of sweet cherry plants and translocation into the fruit and storage organs of the branch.

Phenology, growth and productivity of rice (Oryza sativa l.) under reduced sunlight intensity and foliar nitrogen application

The field experiments related to the study were conducted at Punjab Agricultural University, Ludhiana and Krishi Vigyan Kendra, Bahowal. There were 20 treatment combinations comprising of four levels of sunlight intensity [control (full sunlight), 50% reduction in sunlight light intensity during 15-45(R15-45), 46-75(R46-75) and 76-105(R76-105) DAT] and five levels of foliar nitrogen application [control (only recommended nitrogen, no foliar spray), spray of 3% urea before (NB), midway(NM), afterwards(NA) and midway-afterwards(NMA) the reduction in sunlight intensity in addition to the recommended nitrogen application]. Radiation level of R15-45 significantly preponed (2-5 days) the occurrence of phenological stages from maximum tillering to physiological maturity. Similarly, R46-75 significantly preponed (3-9 days) the occurrences of flag leaf initiation to physiological maturity. The nitrogen level of NB, significantly delayed the occurrence of flag leaf initiation to physiological maturity stages (2-5 days), NM delayed flag leaf initiation to physiological maturity (2-4 days), NA delayed anthesis to physiological maturity (1-4 days) and NMA delayed panicle emergence to physiological maturity (2-5 days). Plant height of rice was significantly increased due to R15-45 (5.21-5.26%) and R46-75 (6.95-7.61%) and also with foliar nitrogen application levels of NB, NM, NA and NMA by 9.95-9.89, 9.65-10.06, 8.06-7.57 and 9.65-9.29 per cent, respectively. Number of tillers m-2 was significantly reduced (4.71-15.99%) under low light conditions and was increased (5.59-23.34%) with foliar nitrogen application. Yield attributes were affected by the reduced sunlight intensity and foliar nitrogen application. Grain yield was significantly reduced as a result of R15-45 (9.19-11.41%), R46-75 (14.29-16.35%) and R76-105 (8.15-10.67%) and foliar nitrogen application levels of NB, NM and NMA resulted in significant increase the grain yield by 9.32-10.19, 5.74-6.38 and 4.59-5.74 per cent respectively, as compared to control.

Creating optimal nutrient conditions in soil and plants during the flower induction process of sweet lime (Citrus limettioides) under calcareous soil conditions to increase the yield

A study was conducted on 6-year-old sweet lime trees on the Mexican lime (Citrus aurantifolia Swingle) rootstock in a randomized complete block design with ten treatments and three replications in southern Fars to determine the appropriate time of plant supplementary feeding to increase flower production and the yield in calcareous soils. In 2016 and 2017, 40 trees that had the same planting and growing conditions, were selected to determine the flower induction time. Ten times (22nd of October, 1st, 11th, and 20th November, December, and January), four branches that had a length of 120 cm and a diameter of half a centimeter were selected on each tree in four geographical directions. At each time, the branches of three trees were ringed at a distance of 120 cm from the tip of the branch, and all the leaves were removed. At the time of flower emergence, the number of flowers was counted. The results showed that the flower induction in these trees was in early December. Based on the results of this experiment and previous research in this field, in September 2017, the 7-year-old trees grafted on the Mexican lime rootstock were treated with the foliar application of nitrogen as urea [CO(NH2)2] and zinc as zinc sulfate (ZnSO4) at three concentrations including 0, 3, and 5 g∙L–1, alone and by combination in two separate pieces in a randomized complete-block factorial design including nine treatments and three replications to increase the yield using elements involved in the flowering. At the harvest time, fruit juice, TSS, TA, vitamin C, average fruit weight, and single tree yield were measured. According to the results, the combination of urea and zinc sulfate at a concentration of 5 g∙L–1 led to an increase in the average fruit weight (58 g) and the yield (68 kg) compared to the control.

Effect of nitrogen fertilizers on agronomic, essential and enzymatic properties of marigold (Calendula officinalis L.) under normal and drought conditions

To investigate the effect of mineral and organic nitrogen fertilizers on some of the quantitative and qualitative reactions of marigold under normal and drought stress, a study was conducted in a split-plot factorial and based on a completely randomized block design with three replications. The first factor included irrigation (normal and water deficit) in the main plot and sub-factor included foliar application of nitrogen fertilizer (control, nitrogen (N), nano-chelate nitrogen (NC) and nitrogen fertilizer+ nano-nitrogen fertilizer (N+NC)) and biofertilizer (control, Azotobacter and Azospirillum) as factorial was placed in sub-plots. Although water deficit stress reduced plant height, flower dry weight, number of seeds per head, 1000-grain weight, biological yield, grain yield and essential oil yield, N + NC foliar application could moderate the adverse effect of water stress on the grain yield, biological yield and essential oil yield. In addition, inoculation of seeds with Azospirillum under water stress conditions could increase the number of seeds per head, 1000-grain weight and essential oil yield compared to the control treatment. NC foliar application and Azotobacter inoculation showed a synergistic effect on the content of proline enzymes and antioxidant activity. Also, simultaneous application of nitrogen + nano-chelate nitrogen foliar application along with seed inoculation with Azospirillum could have a positive effect on increasing flower dry weight, the number of seeds per head, 1000-seed weight, biological yield, grain yield, essential oil yield and proline content.

Foliar application of alpha-ketoglutarate plus nitrogen improves drought resistance in soybean (Glycine max L. Merr.)

The aim of the present research was to understand the impacts of foliar nitrogen and α-oxoglutarate on proline accumulation, photosynthesis, and ammonium assimilation of soybean seedlings subjected to drought stress. The data in the present study demonstrated that foliar α-oxoglutarate and nitrogen significantly enhanced leaf glutamine synthetase (GS) activity, glutamate dehydrogenase (GDH) activity, glutamate content, proline content, relative water content (RWC) and photosynthesis of soybean seedlings exposed to drought stress at each stage. Accordingly, the ammonium content was significantly reduced by foliar α-oxoglutarate and nitrogen. These results suggested that a combination of foliar nitrogen plus α-oxoglutarate had an advantage over either foliar nitrogen or foliar α-oxoglutarate in increasing the proline accumulation under drought stress and a combination of foliar nitrogen plus α-oxoglutarate could better mitigate the adverse impacts of drought stress.

Biofortification of oil quality, yield, and nutrient uptake in Indian mustard (Brassica juncea L.) by foliar application of boron and nitrogen.

Indian mustard (Brassica juncea L.) is an essential oilseed crop that offers important nutrients to human beings. However, the concurrent micronutrient deficiencies including boron (B), sulfur (S), and nitrogen (N) could pose a significant threat to public health. Therefore, this study was conducted at the Punjab Agricultural University, Ludhiana, with nine treatments, i.e., T1-Control (recommended NPK only), T2- borax (0.5%) at flowering, T3-borax (1.0%) at flowering,T4- borax (0.5%) + urea (1.0%) at flowering,T5-borax (1.0%) + urea (1.0%) at flowering, T6-borax (0.5%) at flowering + capsule formation, T7-borax (1.0%) at flowering + capsule formation, T8-borax (0.5%) + urea (1.0%) at flowering + capsule formation, T9-borax (1.0%) + urea (1.0%) at flowering + Capsule formation, replicated three times in a randomized block design for 2 years (2020–2021 and 2021–2022). The foliar application of borax (1.0%) + urea (1.0%) at the flowering and capsule formation stage (treatment T9) was highly efficient in increasing food quality parameters such as crude fiber, total soluble solids (TSS), and protein content with maximum values of 3.77, 24.9, and 27.53%, respectively. Also, maximum yields of seed as well as stover for treatment T9 were 1.376 and 6.625 kg ha−1, respectively. Similarly, the results for B, S, and N concentrations in seed (27.71 mg kg−1, 17.69 mg kg−1, and 2.35%), as well as stover (25.92 mg kg−1, 17.31 mg kg−1, and 0.33%), were maximum in treatment T9. Also, B, S, and N uptake by seed (38.18 g ha−1, 24.40 g ha−1, and 32.05 Kg ha−1) and stover (172.55 g ha−1, 115.44 g ha−1, and 21.99 Kg ha−1) were maximum for the treatment T9 involving borax (1.0%) + urea (1.0%) at the flowering and capsule formation stage. Whereas, the concentration and uptake decreased in the treatments involving the sole application of borax and urea. Therefore, the application of borax (1.0%) and urea (1.0%) at the flowering and capsule formation stage significantly improved the quality parameters, seed and stover yield, nutrient concentration, and uptake over control and could be used to alleviate the B, S, and N deficiency in Indian mustard.

Melatonin Attenuates the Urea-Induced Yields Improvement Through Remodeling Transcriptome and Rhizosphere Microbial Community Structure in Soybean.

Foliar application of nitrogen to enhance crop productivity has been widely used. Melatonin is an effective regulator in promoting plant growth. However, the effects of melatonin and the combination of melatonin and nitrogen on soybeans yields production remain largely unknown. In this study, a field experiment was conducted to evaluate the effects and mechanisms of spraying leaves with melatonin and urea on soybeans. Foliar application of urea significantly increased soybean yields and melatonin did not affect the yields, while combination of melatonin and urea significantly reduced the yields compared to the application of urea alone. A leaf transcriptional profile was then carried out to reveal the underlying mechanism and found that foliar spraying of urea specifically induced the expression of genes related to amino acid transport and nitrogen metabolism. However, foliar application of melatonin significantly changed the transcriptional pattern established by urea application and increased the expression of genes related to abiotic stress signaling pathways. The effects of melatonin and urea treatment on soil microbiome were also investigated. Neither melatonin nor urea application altered the soil microbial alpha diversity, but melatonin application changed rhizosphere microbial community structure, whereas the combination of melatonin and urea did not. Melatonin or urea application altered the abundance of certain taxa. The number of taxa changed by melatonin treatment was higher than urea treatment. Collectively, our results provide new and valuable insights into the effects of foliar application of melatonin to urea and further show that melatonin exerts strong antagonistic effects on urea-induced soybean yields, gene expression and certain soil microorganisms.