Impact of Foliar Spray of NPK and Zn on Soybean for Growth, Yield, Quality, Energetics and Carbon Footprint under Dryland Condition at Indore

Background: Dryland is characterised by drought/dry spell (s) of 10 to 15 days and is the main reason for decline in soybean production. The aim of this study was to develop a strategy of drought amelioration by using foliar sprays and enhancement of yield, quality, energetics and carbon footprint. Methods: A field experiment was carried out at Rajmata Vijayaraje Scindia Krishi Vishwa Vidyalaya, College of Agriculture, Indore, (M.P.) during 2017-18 under spilt-plot design having two main plot treatments viz., foliar application at dry spell (F1), foliar application after dry spell (F2) and seven sub plot treatments i.e. different variants of foliar sprays (DVFS). Different growth, yield, quality, energetic and carbon footprint traits were recorded. The data were analyzed using standard statistical procedures. Result: The highest growth, yield, quality and energetic parameters were recorded for F1 as compared to F2. In case of DVFS, foliar application of water soluble complex fertilizer 19:19:19 (NPK) @ 0.5% + 0.5% ZnSO4 (T4) produced maximum values for growth, energetics, carbon footprint, oil (22.5%) and protein (43.1%) content as well as produced maximum yield.

Effect of Zinc Fortification on Quality, Yield and Economics of Sweetcorn

A field experiment was performed at Agricultural College, Bapatla, ANGRAU, Guntur during kharif season of 2020 to evaluate the efficacy of zinc nutrition on quality, yield and economics of sweetcorn. Experiment was carried out in Randomized Block Design and comprising of nine treatments with three replications. The results disclosed that application of recommended dose of fertilizers along with soil application of 10 kg ha-1 Zn EDTA + two foliar sprays of nano zinc @ 250 ppm at 20 & 40 DAS registered remarkably higher protein content (12.98%) and zinc content (34.59 ppm) in kernel which was considered to be superior over the remaining zinc management practices tried. Also, highest green cob (12,638 kg ha-1), green fodder (19,674 kg ha-1), stover yield (7,590 kg ha-1) and gross returns (₹ 1,93,360 ha-1) was recorded from the treatment with soil application of Zn EDTA @ 10 kg ha-1 + two foliar sprays of nano zinc @ 250 ppm at 20 & 40 DAS along with RDF over control. However, highest net returns (₹ 1,38,664 ha-1) and benefit cost ratio (2.74) was recorded with RDF + ZnSO4 @ 25 kg ha-1 (Soil) + Nano ZnO @ 250 ppm at 20 and 40 DAS (Foliar spray). The effectiveness of Zn EDTA compared to ZnSO4 is responsible for the higher quality parameters and yield of sweetcorn but due to its higher cost, Net returns and B;C ratio are maximum for the plots treated with ZnSO4 making it more economically viable.

Thermal Response of Spring–Summer-Grown Black Gram (Vigna mungo L. Hepper) in Indian Subtropics

The thermal environment of a crop is one of the prime factors enhancing growth and production by regulating its physiological processes at different phenophases. To study the impact of thermal regime on spring–summer-grown black gram (variety Pant Urd 31), an experiment was conducted with different sowing dates (from the first to the third week of March), soil application of cobalt (Co) and foliar sprays of potassium (K) and boron (B) in various combinations in the split–split plot design during 2020 and 2021. The first-week-of-March-sown crop recorded more accumulated growing degree-days (GDD), photothermal units (PTU) and heliothermal units (HTU) with a longer duration than the later sown crop. Higher daily mean temperature during the reproductive stage of the later sown crop compelled it to complete the phenophases earlier than the normally sown crop, leading to yield reduction. Soil application of Co at 4 kg ha−1 and foliar sprays of K at 1.25% and B at 0.2% mitigated the adversities of excess heat irrespective of sowing dates. Variations in GDD and HTU, respectively, explained variations of about 75.8% and 87.3% in the final dry matter accumulation and of 72.9% and 84.8% in seed yield through polynomial regressions in the respective years. The maximum mean thermal use efficiency (TUE) for biomass production (0.24 g m−2/°C/day−1) and seed yield (0.11 g m−2/°C/day−1) were observed with Co soil application and combined foliar sprays of K and B due to higher dry matter production or seed yield with lower heat units accumulation in the first sown crop.

Yield and Nutrient Uptake of Pigeonpea [Cajanus cajan (L.)] as Influenced by Tillage, Nutrient Levels and Foliar Sprays

A field investigation was conducted during two consecutive kharif seasons of 2019-20 and 2020-21 to study the effect of tillage, nutrient levels and foliar sprays on yield and nutrient uptake of redgram on sandy loam soil which was low in available nitrogen, medium in available phosphorus and available potassium. The research was conducted in a split-split plot design, consisting of three tillage practices in main plots, three nutrient levels in sub-plots and three foliar sprays in sub-sub plots. Higher seed yield and nutrient uptake of redgram was recorded with vertical tillage with subsoiler upto 60 cm deep at 1 m interval with application of 125 % RDF and with foliar application of KNO3 1 % twice with 15 days interval at 50 per cent flowering stage.

Efficacy of Selected Insecticides as Replacement for Neonicotinoids in Managing Sweetpotato Whitefly on Poinsettia

Management of sweetpotato whitefly (Bemisia tabaci), one of the most economically important pests of poinsettia (Euphorbia pulcherrima), relies heavily on neonicotinoid insecticides. Growers are seeking insecticide alternatives to neonicotinoids due to market demands. Although several systemic and translaminar insecticides have been suggested as alternatives to neonicotinoids, no published study has simultaneously compared their efficacies against sweetpotato whiteflies. This study compared the efficacies of 10 systemic and translaminar alternative insecticides with those of two systemic neonicotinoids, when all products were applied as foliar spray (twice at 14 d) or substrate drench (once) against sweetpotato whiteflies on poinsettia plants. Sweetpotato whitefly nymph and adult densities were examined 2 weeks before the first application (pretreatment), and weekly after the application for 8 weeks. Results showed that insecticides varied greatly in their efficacy, particularly against adults, and that spray application provided more effective suppression of nymphs than drench application. Spray and drench applications of imidacloprid and dinotefuran were consistently the most effective against sweetpotato whitefly nymphs and adults. Among the neonicotinoid alternatives, cyantraniliprole was the most effective insecticide in reducing sweetpotato whitefly nymph densities by both spray and drench application methods, with efficacy comparable to those of imidacloprid and dinotefuran. Although less effective than cyantraniliprole, foliar sprays of afidopyropen, chloratraniliprole, cyclaniliprole, flonicamid, flupyradifurone, pyrifluquinazon, spirotetramat, and sulfoxaflor + spinetoram were also effective against nymphs and could serve as partners in an insecticide rotation program.

Effect of Varying Levels of Boron and Sulphur on Yields and Nutrient Uptake of Linseed (Linum usitatissimum L.) Grown in a Mollisol

A greenhouse experiment was conducted to study the effect of effect of varying levels of boron and sulphur on yield and nutrient uptake of linseed (Linum usitatissimum L.) grown in a Mollisol. The experiment was conducted under factorial completely randomized design with three replications and consisted of six levels of each of boron (0, 0.5, 1.0, 1.5, 2.0 mg kg−1soil and two foliar sprays of 0.2% boron) and sulphur (0, 10, 20, 30, 40 and 60 mg kg−1soil). The different doses of sulphur and boron and their interaction had significant effect on seed and stover yields, B and S concentrations and uptake by linseed crop indicating a differential requirement of boron and sulphur by the crop. The highest seed yield was recorded under the combined application of 2 mg B kg−1 soil and 60 mg S kg−1 soil.

Silicon Foliar Spray and Substrate Drench Effects on Plant Growth, Morphology, and Resistance to Wilting with Container-Grown Edible Species

The objective of this study was to evaluate silicon (Si) foliar spray and substrate drench effects on plant growth and morphology for container-grown edible crops during greenhouse production, as well as resistance to plant wilting during post-production. In the first greenhouse experiment, basil received Si foliar sprays at 0, 50, 100, 200, and 400 mg∙L–1 Si. In the second greenhouse experiment, Si was applied as either a foliar spray (500 mg∙L–1 Si) or substrate drench (100 mg∙L–1 Si) with six edible crop species. Supplemental Si increased shoot Si levels but had minimal effects on plant growth and morphology, except for parsley, which resulted in distorted growth and phytotoxicity. In the first experiment, 200 and 400 mg∙L–1 Si foliar sprays increased plant resistance to wilt by 2.2 and 2.5 d, respectively; however, this was not observed in the second experiment. All species accumulated Si with the control (no Si) treatments, indicating trace amounts of Si were taken up from the substrate, fertilizer, spray surfactant, and irrigation water. Only cucumber was classified as a Si “accumulator” with a high capacity for Si uptake. Results emphasize the need to conduct preliminary trials with supplemental Si to avoid issues of phytotoxicity.

Response of Hops to Algae-Based and Nutrient-Rich Foliar Sprays

Over recent years, some hopyards of northeast Portugal have presented poorly developed plants and reduced productivity. In this study, an attempt was made to improve the homogeneity of hop fields and restore their productivity by using plant biostimulants as foliar sprays. The experimental apparatus included four field trials carried out in four plots of different plant vigour, as evaluated by farmers over previous years (weak, fair, good and very good). The experiments were arranged as a factorial of foliar treatment (two plant biostimulants containing extracts of seaweed algae and an untreated control) and year (2017 and 2018). The plot and the year influenced greatly almost all the measured variables related to tissue nutrient concentration and crop performance. In the control plots, cone dry matter (DM) yield varied from 83.3 to 394.4 g plant−1 from the weak to the very good plots. In 2018, cone DM yield was significantly higher than in 2017. The use of foliar sprays influenced less the elemental composition of plant tissue than the plot or the year. The use of foliar sprays only increased significantly crop yield in the plot of weak plant vigour. The foliar treatments did not increase α- and β-acid concentration in the cones; in the control treatment of the most productive plot, the values were, respectively, 11.2 and 3.9%. Although seaweed extracts tend to help plants cope with several abiotic and biotic stresses, they showed to be effective in mitigating the stress that is affecting these plants, which probably is poor soil drainage caused by the flooding irrigation system, only under conditions of severe stress.