Explore the vast range of titles available.

A field experiment was carried out during two spring seasons in 2019 and 2020. This study was aimed to increase dry matter weight and crop growth rate of maize. First factor in main plots was nutrition vegetative parts with ascorbic and citric (100 mg l-1) for both of them and humic (1 ml l-1), in addition to the control treatment (spraying of vegetative parts with distilled water only). Second factor in sub-plots was seeds soaking with same acids above, as well as the control treatment (soaking the seeds with distilled water only). Randomize complete block design in split plot arrangement was used with three replications. The results showed a significant superiority of seeds soaking in humic acid for traits of number of days from planting to 75% anthesis  and silking (66.4 and 66.3 day) and (72.3 and 72.3 day), plant height (194.0 and 230.8 cm), leaves area plant-1 (6969.5 and 6570.2 cm2), leaf area index (3.71 and 3.50), dry matter weight (11.6 and 12.2 ton ha-1), crop growth rate (3.0 and 3.2 g cm-2 day-1) and chlorophyll leaf content (60.2 and 69.5 SPAD) for both seasons, respectively. Effect of vegetative parts nutrition and interaction effect of both studied factors was non-significant for most traits. It can be concluded that seeds soaking in humic acid improved growth traits. It can be recommended to soak seeds of maize before planting in humic acid at concentration of 1 ml l-1.

The scarcity of water resources in arid and semi-arid areas is considered a threat to agricultural sustainability. Therefore, approaches are needed to rationalize use of irrigation water without reducing crop productivity or degrading soil properties. The objective of this study was to investigate the effect of different organic amendments (O1 = control, O2 = compost, and O3 = vermicompost) combined with different rates of nano- zinc foliar spraying (Zn1 = 0, Zn2 = 1 and Zn3 = 2 gm/L), under irrigation supplements (I1 = 100%, I2 = 85%, and I3 = 65% of water requirements) on clay soil characteristics, on the production of Egyptian barley Giza 126. Over two successive winter growing seasons, 2018/2019 and 2019/2020, field experiments were conducted as a split-split plot design with three replications. The results show that using vermicompost is an appropriate organic amendment to improve the physical and chemical properties of soils as compared with compost. Application of vermicompost led to a reduction in soil salinity (ECe), exchangeable sodium percentage (ESP), and soil bulk density (BD), of −5.67%, −5.44%, and −2.21%, respectively; there was a significant increase in soil organic carbon (SOC), available nitrogen (A.N), and field capacity (F.C.), of 43.75%, 14.37%, and 18.65%, respectively, compared with unamended soil (O1). The maximum values for grain yield were increased by 13.2% and 14.9% in both seasons, respectively, and the irrigation water productivity of barley was increased more than compost and control. Vermicompost increased the irrigation water productivity for grain (1.69 and 1.69 kg grain m−3) and straw (1.23 and 1.17 kg straw m−3) in the first and second season, respectively. Similar trends were also observed from treatments on the water applied, stored water, and water application efficiency. Application of vermicompost and nano-Zn foliar spraying could be exploited for the development of barley growth and yield, which are enhanced under water-saving irrigation strategies.

Little is known about transport of Zn from leaves to other plant organs. The present study tested a range of Zn forms applied foliarly for their suitability to provide adequate Zn nutrition to wheat (Triticum aestivum L.). Transport of65Zn applied either to leaves or to one side of the root system was also studied. Inorganic (ZnO, ZnSO4) and chelated sources of Zn (ZnEDTA, glycine-chelated Biomin Zn) applied foliarly provided sufficient Zn for vigorous growth. Zinc concentrations in roots and shoots were in the sufficiency range, except in the −Zn control. Foliar treatments with ZnSO4and chelated Zn forms resulted in shoot Zn concentrations in 7-week-old plants being about two-fold greater than those in plants supplied with Zn in the root environment or via foliar spray of ZnO. Adding surfactant to foliar sprays containing chelated forms of Zn did not cause negative growth effects, but surfactant added to ZnO or ZnSO4foliar sprays decreased shoot growth. Adding urea to the ZnO foliar spray had no effect on shoot growth. Foliarly-applied65Zn was translocated to leaves above and below the treated leaf as well as to the root tips. Stem girdling confirmed that65Zn transport toward lower leaves and roots was via the phloem. Split-root experiments showed intensive accumulation of65Zn in the stem and transport to all leaves as well as to the root tips in the non-labelled side of the root system. Foliar application of Zn in inorganic or organic form is equally suitable for providing adequate Zn nutrition to wheat. Phloem transport of Zn from leaves to roots was demonstrated.

By foliar application of a range of methanol solutions (0, 2.5, 5, 7.5, 10 %, v/v) on leaves of salt-stressed soybean seedlings, and comparing changes in plant height and relative electrolytic leakage, the appropriate concentration of foliar methanol for mitigating of salt injury to soybean was selected. On this basis, foliar application of the appropriate concentration of methanol solution was conducted on salt-stressed soybean cv. Jackson (the salt-sensitive) and cv. Lee68 (the salt-tolerant) seedlings. By comparing changes in plant dry matter weight, leaf area and net photosynthetic rate (Pn), root and leaf thiobarbituric acid reactive substances (TBARS) contents, and plant Na⁺, K⁺contents and Na⁺/K⁺ratios, physiological effects of foliar methanol application were analyzed. The results showed that: Use of different concentrations of methanol solution for foliar spraying all had ameliorative effects for salt-treated soybean seedlings, of which, 5 % concentration was the appropriate. Under salt stress, plant dry matter weight, leaf area and Pn of cv. Jackson and cv. Lee68 seedlings decreased significantly, TBARS contents in roots and leaves were increased significantly, K⁺contents in soybean plants declined, while Na⁺contents and Na⁺/K⁺ratios increased remarkably, and as a whole, the changes in cv. Jackson were higher than those in cv. Lee68. Under salt stress plus leaf spraying of 5 % methanol, plant dry matter weight, K⁺contents, leaf area and Pn of cv. Jackson and Lee68 seedlings were restored, root and leaf TBARS contents, plant Na⁺contents and Na⁺/K⁺ratios were all reduced, of which cv. Jackson displayed a more pronounced effect.

Microalgae represent a potential sustainable alternative for the enhancement and protection of agricultural crops. Cellular extracts and dry biomass of the green alga Acutodesmus dimorphus were applied as a seed primer, foliar spray, and biofertilizer, to evaluate seed germination, plant growth, and fruit production in Roma tomato plants. A. dimorphus culture, culture growth medium, and different concentrations (0, 1, 5, 10, 25, 50, 75, and 100 %) of aqueous cell extracts in distilled water were used as seed primers to determine effects on germination. Seeds treated with A. dimorphus culture and with extract concentrations higher than 50 % (0.75 g mL⁻¹) triggered faster seed germination—2 days earlier than the control group. The aqueous extracts were also applied as foliar fertilizers at various concentrations (0, 10, 25, 50, 75, and 100 %) on tomato plants. Extract foliar application at 50 % (3.75 g mL⁻¹) concentration resulted in increased plant height and greater numbers of flowers and branches per plant. Two dry biomass treatments (50 and 100 g) were applied 22 days prior to seedling transplant and at the time of transplant to assess whether the timing of the biofertilizer application influenced the effectiveness of the biofertilizer. Biofertilizer treatments applied 22 days prior to seedling transplant enhanced plant growth, including greater numbers of branches and flowers, compared to the control group and the biofertilizer treatments applied at the time of transplant. The A. dimorphus culture, cellular extract, and dry biomass applied as a biostimulant, foliar spray, and biofertilizer, respectively, were able to trigger faster germination and enhance plant growth and floral production in Roma tomato plants.

[This corrects the article DOI: 10.3389/fpls.2026.1739257.].

Damages of the (agro)ecosystem by extensive use of chemical fertilizers and pesticides, the global dying of bee populations possibly linked to pesticide spraying, and stricter regulations for pesticide use together with successful use of microbials in IPM programs are pushing on the development and commercialization of new microbial products and a large and growing biostimulants and biocontrol market. This review focuses on microbial inoculants including bacteria, fungi, and viruses used as biostimulant or biocontrol agent for foliar application and covers all important steps from inoculant development to successful field application. Topics presented comprise typical spraying equipment including the importance of the spraying process and relating effects, furthermore formulation development including classification and adjuvants, and thirdly regulatory aspects as currently applied or under discussion. Microbial inoculants for foliar spray reported in scientific literature are summarized and contrasted with selected commercial products. Special attention is given to factors most important in microbial spray: (a) type of active ingredient (bacteria, fungi, viruses), (b) mode of action (ingestion, contact, competition), (c) interaction with the plant leaf surface, (d) droplet size in terms of microbe concentration and leaf coverage, and (e) environmental conditions during spraying. Finally, we want to emphasize that timely administration is of utmost importance for successful spraying and maximum efficacy. This might be supported by weather stations and disease/pest models as an important step towards precision farming.

Background Application of exogenous glycine betaine (GB) and exogenous salicylic acid (SA) mitigates the adverse effects of salinity. Foliar spraying with exogenous GB or SA alleviates salt stress in plants by increasing leaf gas exchange and stimulating antioxidant enzyme activity. The effects of foliar application of exogenous GB and SA on the physiology and biochemistry of cotton seedlings subjected to salt stress remain unclear. Results Results showed that salt stress of 150 mM NaCl significantly reduced leaf gas exchange and chlorophyll fluorescence and decreased photosynthetic pigment quantities and leaf relative water content. Foliar spray concentrations of 5.0 mM exogenous GB and 1.0 mM exogenous SA promoted gas exchange and fluorescence in cotton seedlings, increased quantities of chlorophyll pigments, and stimulated the antioxidant enzyme activity. The foliar spray also increased leaf relative water content and endogenous GB and SA content in comparison with the salt-stressed only control. Despite the salt-induced increase in antioxidant enzyme content, exogenous GB and SA in experimental concentrations significantly increased the activity of glutathione reductase, ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, and decreased malondialdehyde content under salt stress. Across all experimental foliar spray GB and SA concentrations, the photochemical efficiency of photosystem II ( F V / F M ) reached a peak at a concentration of 5.0 mM GB. The net photosynthetic rate ( P n ) and F V / F M were positively correlated with chlorophyll a and chlorophyll b content in response to foliar spraying of exogenous GB and SA under salt stress. Conclusions We concluded, from our results, that concentrations of 5.0 mM GB or 1.0 mM SA are optimal choices for mitigating NaCl-induced damage in cotton seedlings because they promote leaf photosynthesis, increase quantities of photosynthetic pigments, and stimulate antioxidant enzyme activity. Among, 5.0 mM GB and 1.0 mM SA, the best performance in enhancing endogenous GB and SA concentrations was obtained with the foliar application of 1.0 mM SA under salt stress.

The search for an effective zinc fertilizer and its application method to effectively increase zinc content and enhance aroma in rice grains is a crucial objective. In this study, a 2-year field plot experiment was conducted to investigate the influence of ZnO NPs foliar spraying on rice quality, grain zinc and aroma content, along with exploring the physiological mechanisms underlying these effects. Our results demonstrated that the rice breakdown value and taste value of foliar spraying zinc oxide nanoparticles were improved by 31.0–41.7% and 8.2–13.0% compared with CK (control treatment involved spraying water), improving the tasting and steaming quality of rice. While Fe and Cu content in grains decreased for the application of zinc oxide nanoparticles, zinc oxide nanoparticles foliar spraying significantly increased the zinc content and accumulation of grains by 33.6–65.1% and 37.8–74.7%, respectively. Further analysis showed that the sprayed zinc oxide nanoparticles achieved effective enrichment of zinc in edible parts and increased the final bioavailability of Zn. In addition, foliar spraying of zinc oxide nanoparticles significantly increased activities of nitrate reductase and glutamine synthetase in leaves, which elevated nitrogen content in leaves and grains, and ultimately enhanced 2-acetyl-1-pyrroline (2-AP) content in grains at maturity by 6.1–21.4% compared to CK. Our findings indicated that zinc oxide nanoparticles can be practically applied as a foliar fertilizer at the gestation for quality improvement, zinc enrichment and aroma enhancement of rice grains.

Aims It is imperative to understand the synergetic actions of Melatonin (MET) and salicylic acid (SA) in counteracting drought stress. A pot experiment was performed to investigate the interactive effects of exogenously applied MET and SA on morphology, physiology, and biochemical characteristics of drought-stressed canola ( Brassica napus ). Methods Two cultivars (Super canola and Faisal canola) were used. MET (0.1 µM) and SA (0.50 mM) were applied as seed priming and foliar spray. Plants were exposed to severe drought (45% field capacity) at the reproductive stage. Results Drought stress caused a significant reduction in shoot length (19%), plant fresh (15%) and dry (17%) biomass, yield (30%), photosynthetic rate (43%), water potential (29%) and osmotic potential (33%) values. Increased activity of free amino acids (20%), total soluble sugars (5%), and different antioxidant enzymes like catalase (27%), peroxidase (23%), superoxide dismutase (20%) and ascorbate peroxidase (35%), were recorded under drought. Seed priming and foliar application of MET and SA reduced the negativity of drought. Priming of seeds with MET, as well as synergetic application of MET priming and SA foliar spray, were the most effective treatments, showing the most significant growth criteria (22% increase in plant height, 46% in fresh and 40% in dry biomass), yield components (49%), water (54%) and osmotic potential (28%), and endogenous MET (17%) and SA (16%) content. Super canola cultivar showed better growth than Faisal canola. Conclusion Study showed that the synergetic application of MET and SA has the potential to induce stress resistance and enhance canola plants' growth under drought.