Dry Biomass Yield Research Articles

Evaluation of the Effect of Perennial Forage Legume (Desmodium uncinatum) Intercropping with Sugarcane on Forage and Major Crop Yield, and Economic Effectiveness at Wondo Genet, Sidama, Ethiopia

This study was initiated to evaluate the effect of intercropping perennial forage legume (Desmodium uncinatum) with sugarcane on main crop and forage yield at Wondo genet. Five treatments (Sole main crop (Sugarcane), Sole Desmodium uncinatum and three seeding rates (full recommended rate, 75 % and 50 % of full recommended rate) were used for forage legume when intercropped with Sugarcane in randomized complete block design with three replications. Millable cane height, internodes number and internodes length showed non-significant effect due to different intercropping systems while cane yield (ton/ha) and green tops yield (ton/ha) did show significant difference with different intercropping systems. Experimental results reveal that different intercropping systems had no significant impact (p=0.05) on plant height, fresh biomass yield and dry biomass yield of intercrops (Desmodium uncinatum). Partial LER of sugarcane (LERs) was maximum when sugarcane was intercropped with full seeding rate of desmodium. Maximum LER of inter crops (Desmodium) (LERd) and maximum total LER (LERt) was reported in sugarcane + full seeding rate of desmodium intercropping system (1.04 and 1.80 respectively). Lowest LERt (1.36) was recorded in Sugarcane + 75% seeding rate of desmodium intercropping system. Sugarcane yield (t/ha) in sugarcane + full seeding rate of desmodium intercropping system was higher than all other combined intercropping systems. All LERt were greater than one and it indicates that the intercrop is more productive than the respective sole cropping. Keywords: Sugarcane, Intercropping, Desmodium, Land equivalent ratio, Yield DOI: 10.7176/FSQM/114-02 Publication date: April 30 th 2022

Biofixation of CO2 from a power plant through large-scale cultivation of Spirulina maxima

Using microalgae for biological fixation of CO2 is an attractive option for limiting the amount of CO2 emissions from power plants. In this experiment, Spirulina maxima was successfully grown utilizing direct flue gas emitted from the Ratchaburi Electricity Generating Company Limited, Thailand. The aims of this study were to determine the optimal conditions for large-scale culturing of this alga for maximum biomass as well as CO2 abatement. The results showed that the carbon source of NaHCO3 can be reduced from standard Zarrouk medium of 16.8 down to 8 g/L, producing fresh and dry weight biomass yields of 206 and 21.57 kg, respectively, within 30 days of cultivation. The optimal initial pH was 9.0, thereby reducing the lag phase of algal growth and producing the best fresh weight yield. The natural light intensity (with CO2) prevented stressed and weakened the algal cells, resulting in extending the algal life and producing the highest yields of fresh and dry weight. The morphology of algal cells was examined following culturing at pH 9 and pH10.5. The algal cells produced at pH 9 had a helical shape of the trichome, a separate septum and thylakoids, and the vacuoles were distributed throughout the cell, while algal cells cultured in medium with an initial pH of 10.5 mostly had the straight form, with the septum and thylakoids being unclear. The maximum CO2 level used was 2.5 times base level of the CO2 (141.75 g CO2/h) produced the highest biomass of fresh and dry weights. The optimal culture for CO2 gas was the continuous culture system and using CO2 efficiently, which encouraged algal growth and produced higher biomass yields than those from the batch culture system. There was no significant difference in nutritional value terms for the protein and pigments contents between the algal biomass products in assay with and without CO2 Furthermore, there was no metal contamination in algal biomass. The results indicate that the use of waste CO2 from a power plant can be successfully used for large-scale Spirulina production.

Effects of Post-Emergence Herbicides and Period of Johnsongrass (Sorghum halepense (L.) Pers.) Control on Growth and Yield of Sunflower Crops

Sunflower is an important industrial crop since it is grown all over the world for oil production, while Johnsongrass (Sorghum halepense (L.) Pers.) is characterized by great competitiveness and can severely impair plant growth and crop productivity. Thus, a two-year field experiment was conducted to evaluate the impact of Johnsongrass control practices on plant growth, seed yield, and oil content of sunflower crop. The results indicated that Johnsongrass competition negatively affected sunflower growth and productivity as the lowest values of height, dry biomass, seed, and oil yields were recorded at the weed-infested treatment, followed by the weed infested for 30 days after sowing. All the other treatments had a positive effect on vegetative and yield parameters. Moreover, fluazifop-p-butyl, quizalofop-p-ethyl, and the combination of fluazifop-p-butyl and imazamox effectively controlled Johnsongrass. Specifically, in 2020, the lowest dry weight of Johnsongrass was observed in the plots where fluazifop-p-butyl + imazamox were applied. Thus, the results of this study clearly showed that the use of the above-mentioned herbicides can improve the seed and oil yield of a sunflower crop by managing Johnsongrass, while the competition of this rapidly growing weed for a short period of 30 days can significantly reduce crop yield.

Variability of the essential oil composition of cultivated populations of Salvia lavandulifolia Vahl

AbstractSpanish sage or lavender sage (Salvia lavandulifolia Vahl) is an aromatic plant with a high economic potential in agriculture because of its rusticity and low chemical inputs. However, the presence of numerous chemotypes hinders the supply of homogeneous crops to the industry and makes the selection and the standardising of the plant material necessary. With this aim, our group achieved an extensive population survey of this species across the Iberian Peninsula to investigate the variability of this species and started a selection program based in multienvironment trials. Thus, 12 wild populations of S. lavandulifolia have been grown in two different localities and their dry biomass production, yield, and composition of essential oil have been monitored during 2 yr of cultivation to evaluate the effect of the genotype × environment interaction on these traits. Each population presented a clearly differentiated composition of the essential oil, although camphor (15.3% average), 1,8‐cineole (15.0%), α‐pinene (11.3%), β‐pinene (8.5%), and limonene (7.5%) were the main compounds. Other compounds like p‐cymene, γ‐terpinene, bornyl acetate, spathulenol, or viridiflorol were only present in some samples. The yield of essential oil ranged from 0.9 to 2.3 g per 100 g dry biomass, and the dry biomass from 76 to 322 g plant−1. Despite the high variability of these traits, we inferred that the essential oil composition in S. lavandulifolia is chiefly determined by genetics which suggests that individual plants (clones) with a favorable composition for a specific application could be selected and bred with a homogeneous quality over time.

Estimation of direct-seeded guayule cover, crop coefficient, and yield using UAS-based multispectral and RGB data

Guayule (Parthenium argentatum, A. Gray), a perennial desert shrub, produces high-quality natural rubber and is targeted as a domestic natural rubber source in the U.S. While commercialization efforts for guayule are on-going, crop management requires plant growth monitoring, irrigation requirement assessment, and final yield estimation. Such assistance for guayule management could be provided with remote sensing (RS) data. In this study, field and RS data, collected via drones, from a 2-year guayule irrigation experiment conducted at Maricopa, Arizona were evaluated. In-season field measurements included fractional canopy cover (fc), basal (Kcb) and single (Kc) crop coefficients, and final yields of dry biomass (DB), rubber (RY), and resin (ReY). The objectives of this paper were to compare vegetations indices from MS data (NDVI) and RGB data (triangular greenness index, TGI); and derive linear prediction models for estimating fc, Kcb, Kc, and yield as functions of the MS and RGB indices. The NDVI and TGI showed similar seasonal trends and were correlated at a coefficient of determination (r2) of 0.52 and a root mean square error (RMSE) of 0.11. The prediction of measured fc as a linear function of NDVI (r2 = 0.90) was better than by TGI (r2 = 0.50). In contrast to TGI, the measured fc was highly correlated with estimated fc based on RGB image evaluation (r2 = 0.96). Linear models of Kcb and Kc, developed over the two years of guayule growth, had similar r2 values vs NDVI (r2 = 0.46 and 0.41, respectively) and vs TGI (r2 = 0.48 and 0.40, respectively). Final DB, RY, and ReY were predicted by both NDVI (r2 = 0.75, 0.53, and 0.70, respectively) and TGI (r2 = 0.72, 0.48, and 0.65, respectively). The RS-based models enable estimation of irrigation requirements and yields in guayule production fields in the U.S.

Rust (Puccinia emaculata) Management and Impact on Biomass Yield in Switchgrass.

Rust, putatively caused by Puccinia emaculata, is a widespread and potentially damaging disease of switchgrass, a crop produced as feedstock for livestock and bioenergy. Azoxystrobin, chlorothalonil, and myclobutanil were applied at 1-, 2-, 3-, or 4-week intervals for 12 to 14 weeks to the vegetatively propagated switchgrass cultivar Cloud Nine to assess fungicide selection and application interval for the control of rust as well as the impact of this disease on switchgrass biomass yield. Although rust severity significantly differed among study years, azoxystrobin and myclobutanil were often equally and more effective than chlorothalonil at controlling rust, with superior disease control coming at shorter application intervals compared with extended application intervals. Year, product, application interval, and product × interval significantly impacted dry biomass yield, which was greatest in 2016 and lowest in 2014. Dry biomass yield protection was significantly better with azoxystrobin and myclobutanil applications than with chlorothalonil or no fungicide. Linear regression models with the final disease rating, as well as with the area under disease progress curve in each year, were significant, but coefficients of determination were low to moderate (0.21 < R2 < 0.60), indicating that rust response and subsequent disease impact on dry biomass yield were impacted by other factors. From our models, an estimated 3 to 5% biomass decline was calculated for each 10% increment in rust-related leaf necrosis observed at the final September rating date. With rust-related leaf necrosis ≥80% by 1 September in each of 4 study years, biomass yield may be reduced by 24 to 40% if rust problems are not managed in switchgrass crops.

Variation in actual corn (Zea mays L.) evapotranspiration, single, and dual crop coefficient under different point source irrigation systems in a semiarid region

Close management of irrigation could have considerable impacts on water resources, especially for cropping systems dominated by corn. The experiment was carried out to compare the influence of porous capsule irrigation (PCI), surface drip irrigation (DI), and subsurface drip irrigation (SDI) systems, with or without mulching, on actual evapotranspiration (ETc act), crop coefficients (Kc single and Kc dual), biomass yield, and water use efficiency (WUE) of corn in a semiarid region of Iran. The experiment was arranged in a split-plot design with the three irrigation systems assigned to the main plots and two mulching (with or without foil type) treatments (M1 and M2) assigned to the sub-plots. The corn ETc act varied significantly (P < 0.05) with the different irrigation systems, being (mm) 389.8 for PCI, 377.0 for DI, and 372.8 for SDI. The highest Kc average and Kcb (0.82 and 1.22) and the lowest Ke (0.12) were observed under the PCI system. The dry and wet biological biomass yields were highest (29.98 and 107 t/ha) under the PCI + M1 treatment, and the lowest (23.19 and 58.54 t/ha, respectively) were under the DI + M2 treatment. The highest WUE (7.89 kg/m3) was also observed under the PCI + M1 treatment; PCI produced the best biological biomass yield, WUE and IWUE in comparison to DI and SDI systems. Accordingly, the PCI system could be a viable alternative to drip irrigation for areas with scarce water resources, particularly for smallholder farmers.

Ecotoxicity and bioremediation potential assessment of soil from oil refinery station area

PurposeThe aim of the present study was to evaluate the toxicity and biodegradation potential of oil hydrocarbons contaminated soil samples obtained from different depths at an oil refinery station area. An approach involving chemical, microbiological, respirometry and ecotoxicity assessment of soil polluted by oil hydrocarbons was adopted, in order to determine the biodegradability of pollutants and ecotoxicological effects of natural attenuation strategy.MethodsThe ecotoxicity of soil samples was evaluated using an ostracod test kit and a seed germination test. The results of the phytotoxicity assay were expressed as a percentage of seedling emergence and as the relative yield of fresh and dry biomass compared to control plants. The intrinsic biodegradation potential of the contaminated soil was examined using a Micro-Oxymax respirometer. Intrinsic biodegradation rates were estimated from the slopes of linear regressions curves plotted for cumulative O2 uptake. The obtained values were then entered in the mass balance equation for the stoichiometric reaction of hydrocarbon decomposition and converted per kg of soil per day.ResultsAlthough the tested contaminants were biodegradable in the respirometric assay, they were slightly to moderately toxic to plants and extremely toxic to ostracods. The noxious effects raised with the increased concentration of contaminants. The monocotyledonous oat was more tolerant to higher concentrations of oil hydrocarbons than the other test plants, indicating its greater suitability for soil reclamation purposes.ConclusionBy assessing phytotoxicity and effect on ostracod mortality and progress of soil self-decontamination process, proper approach of reclamation of demoted area can be provided.

ВИРОЩУВАННЯ ЕНЕРГЕТИЧНОЇ ВЕРБИ В УМОВАХ ЗАХІДНОГО ПОЛІССЯ

The research results of influence of the planting density, fertilization and soil type on the productivity of the energy willow in the conditions of Western Polissia are presented. On average over five years of research in the cultivation of energy willow it was found that the highest yield of dry biomass 102.9 t/ha was obtained on dark gray light loamy soil with a planting density of 20 thousand pcs/ha and fertilizer application at the rate of N60 P200 K200. The lowest yield of dry biomass was at planting density of energy willow of 10 thousand pcs/ha in the variant without fertilizers on dark gray light loamy soil and sod-podzolic cohesive sandy soil – 49.1 and 26.9 t/ha, respectively. The mineral fertilizer application with rate of N60 P100 K100 ensured an increase in the yield of dry biomass by 13.5 and 7.5 t/ha depending on the type of soil. The increase of phosphorus and potash fertilizers rate to 200 kg a.i./ha contributed to an increase in dry mass up to 23.6 and 13.0 t/ha compared to the variant without fertilizers. A similar result was obtained on sod-podzolic cohesive-sandy soil. The lowest indicators were in the variant without fertilizers at the planting density of 10 thousand pcs/ha – 26.9 t/ha, 15 thousand pcs/ha – 30.2 t/ha and 20 thousand рcs/ha – 35.6 t/ha dry biomass. The application of mineral fertilizers with rate of N60P100K100 for all planting densities increased the dry biomass yield to 34.4; 38.5; 45.3 t/ha, respectively. Increase of phosphorus and potash fertilizers rate up to 200 kg a.i./ha against the background of N60 contributed to an increase of energy willow yield up to 39.9 t/ha (with a planting density of 10 thousand pcs/ha), 44.1 t/ha (15 thousand pcs/ha) and 52.3 t/ha (20 thousand pcs/ha) of dry biomass. On average for five years, the application of fertilizer with N60P200K200 rate on dark gray light loamy soil, and at planting density of 20 thousand pcs/ha provided the highest yield of solid biofuel from energy willow of 22.7 t/ha and energy of 363 GJ/ha, while on sod-podzolic cohesive-sandy soil under the same growing conditions the yield of solid biofuel from willow was less by 11.1 t/ha and energy of 178 GJ/ha. Keywords: energy willow, dry biomass, solid biofuels, energy, soil.

Growth and yield performance of sorghum (Sorghum bicolor L.) crop under anthracnose stress in dryland crop-livestock farming system

Abstract Dual-purpose sorghum response to anthracnose disease, growth, and yield was undertaken in Derashe and Arba Minch trial sites during March–June 2018 and 2019. Five sorghum varieties and Rara (local check) were arranged in a randomized complete block design with four replications. Variety Chelenko exhibited the tallest main crop plant height (430 cm) while Dishkara was the tallest (196.65 cm) at ratoon crop harvesting. Rara had a higher tiller number (main = 6.73, ratoon = 9.73) among the varieties. Dishkara and Chelenko varieties produced 50 and 10% more dry biomass yield (DBY) than the overall mean DBY, while Konoda produced 40% less. Although the anthracnose infestation was highest on the varieties Konoda (percentage severity index [PSI] = 20.37%) and NTJ_2 (PSI = 32.19%), they produced significantly (p &lt; .001) higher grain yield (3.89 t/ha) than others. Under anthracnose pressure, Chelenko and Dishkara varieties are suggested for dry matter yield while NTJ_2 for grain yield production in the study area and similar agroecology.

Morphological variability, density and yield of Trifolium repens in different ecological and coenotic conditions

White clover (Trifolium repens L.) is a valuable melliferous, pasture and a promising species for use as a medicinal raw materials. T. repens herb contains ascorbic acid, carotene, alkaloids, glycosides and other substances. Fourteen coenopopulations of T. repens were studied on the territory of the Republic of Tatarstan. The assessment of habitats of T. repens was carried out by indicator methods using the ecological scales of G. Ellenberg. The density of coenopopulations, comparative morphometric analysis and reserves of dry aboveground biomass are analyzed in this article. It was found that the soils in the subtaiga subzone are weakly acidic, fresh in terms of moisture, with a nitrogen content above average; soils in the north of the broad-leaved subzone are dry and periodically fresh, with a slightly acidic reaction and an average content of mineral nitrogen; and the soils in the south of the broad-leaved subzone are dry and periodically fresh, predominantly neutral, with a nitrogen content above average. A comparative analysis of the scoring of soil characteristics with the content of the main nutrients in the soil has been carried out. T. repens coenopopulations in the north of the broad-leaved subzone have of low density, and high biomass shoots are formed. The yield of the studied T. repens plants is from 21-178 kg of dry weight/ha. The highest yields of dry aboveground biomass of plants was observed in the northern deciduous subzone. We recommend the highest-yielding coenopopulations of T. repens for harvesting plant material.

Effect of Farmyard Manure and Blended Fertilizer Rates on Yield and Yield Components of Hot Pepper (&amp;lt;i&amp;gt;Capsicum annuum&amp;lt;/i&amp;gt; L.) in East Wollega Zone, Ethiopia

Hot Pepper (Capsicum annuum L.) is an important spice and vegetable crop in Ethiopia. However, soil fertility depletion (nutrient deficiency) is one of the vital yield limiting factors in production. This experiment was conducted with the objective of determining the effects of combined use of different levels of Farmyard manure and blended fertilizer (NPSZnB) rate on yield and yield components of hot pepper and to identify the optimum combination of two fertilizers levels that give a higher yield of hot pepper. Mareko Fana variety was used for experiment. The treatments consisted of three levels of farmyard manure (0, 2, and 4 t/ha) and five levels of bended fertilizers (0, 25, 50, 75 and 100 kg/ha) combined factorially and arranged in a Randomized Complete Block Design with three replications. Analysis of the results showed that the interaction of farmyard manure and blended fertilizer significantly (p<0.05) affect most of the parameters studied. Application of 4t/ha farm yard manure and 100kg/ha blended fertilizers results showed that higher plant height 67.05cm, number of primary branches (7.82), number of leaf (331.72), number of fruit per plant (29.61), fruit length (10.49cm), total fresh fruit yield (5.60 t/ha), marketable yield (2.34 t/ha), total dry fruit yield (2.46 t/ha), biomass yield (4.96 t/ha) and harvest index (0.39) whereas lowest marketable yield (1.13 t/ha) and total dry fruit yield (1.25 t/ha), were recorded from unfertilized treatment. Therefore, the result of this study has showed that levels of farmyard manure and blended fertilizer in the study areas could be significantly enhances yield and yield components of hot pepper if 4 t/ha of Farmyard manure and 100 kg/ha of blended fertilizer are integrated and applied to hot pepper. Moreover, farmers in the study area should be encouraged to use integrated nutrient management system rather than inorganic fertilizer alone since such system helps not only supply nutrients but also improves physicochemical properties of the soil, thereby significantly enhances yield and yield component of hot pepper. Furthermore, as the study was conducted only at one location for a single season, it is also recommended to repeat the study across representative locations of the district both under rain fed and irrigated conditions.

Efecto de relaciones Cl- y Na+ en soluciones nutritivas sobre el rendimiento de jitomate (Solanum lycopersicum L.) en hidroponía

Intensive tomato (Solanum lycopersicum L.) production in coastal areas of Sinaloa is exposed to significant amounts of Cl and Na deposited by sea breezes and irrigation water, which affects the yield of this vegetable. The aim of this study was to evaluate three percentage ratios of Cl-/anions (25/100, 50/100 and 75/100) and three percentage ratios of Na+/cations (25/100, 50/100 and 75/100) in the nutrient solution on mineral composition, dry matter production and yield of tomato. The experimental design was completely randomized with a 32 factorial arrangement and four replications. Analysis of variance and mean comparisons were performed (Tukey, P ≤ 0.05). Cl and Na concentrations in tomato leaves, stems and fruits increased significantly with increasing ratios of Cl-/anions and Na+/cations in the nutrient solution. The 75/100 Cl-/anions ratio reduced (P ≤ 0.05) the Ca concentration in leaves, while the 75/100 Na+/cations ratio decreased (P ≤ 0.05) K concentrations in leaves and stems. Both ratios reduced aerial dry biomass (48 and 25.8 %, respectively) and tomato yield (50.8 and 45.7 %, respectively). The results indicate that tomato plants grown with the 75/100 percentage ratio of Cl-/anions or the 75/100 percentage ratio of Na+/ cations absorb excessive amounts of Cl or Na, which causes ionic imbalance (especially of K+ and Ca2+) and affects dry matter production and yield.

Integration of raised beds, mulching and stem training for weed management in tomato under mid-hill conditions of Himachal Pradesh

A field experiment was conducted at the Research Farm of Vegetable Science, DR YSPUHF, Nauni, Solan (HP), India to evaluate the effect of polythene mulches, planting methods and training systems on weed control and yield response of tomato crop. The experiment was laid out in factorial randomized block design with twelve treatments and replicated thrice. The consortium effect of raised bed (RB) + black polythene mulch (BPM) + two stem training have recorded less weed density (142.00/m2), greater weed control efficiency (64.64%), less fresh (82.00 g/m2) and dry weed biomass (13.00 g/m2) and higher yield (100.12 t/ha). The dominance of Cyperus rotundus, Echinochloa crus-galli and Galinsoga parviflora weed species was also less with the integration of raised bed, black polythene mulch and two stem training system. This practice helps in the tomato production with better water conservation; weed management and improved tomato yield under mid-hill conditions of Himachal Pradesh.

Essential Oil Yield and Yield Related of Basil (Ocimum basilicum L) as Affected by NPS and Nitrogen Fertilizer Rates at Wondo Genet, Southern Ethiopia

The experiment was conducted on experimental field of Wondo Genet Agricultural Research Center (WGARC), southern Ethiopia under supplementary irrigation in 2017- 2018 cropping season, to assess the effects of NPS and N fertilizer rates on essential oil yield and yield related traits of basil. The experiment consisted of four rates of nitrogen (0, 23, 46, and 69 kg ha-1) and four rates of NPS fertilizer (0, 50,100 and 150 kg ha-1). The treatments were arranged in factorial combination using randomized complete block design (RCBD) with three replications. The analysis of variance revealed that the main effects of NPS and N fertilizer rates significantly affected plant height, number of leaves plant-1 and dry stem weight plant-1. The tallest plant height (32.87 cm) and highest dry stem weight (41.86 g plant-1) were recorded from 100 kg ha-1 NPS rate. Similarly, the tallest plant (31.90 cm) and highest dry stem weight (42.78 g plant-1) were recorded from the highest (69 kg N ha-1) rate. On other hand, the interaction effects of NPS and N fertilizer rates also significantly affected number of primary branches plant-1, fresh leaf weight plant-1, fresh stem weight plant-1, fresh inflorescence weight plant-1, aboveground dry biomass and essential oil yield of basil. Significantly, the highest fresh leaf weight (319.36 g plant-1) and fresh stem weight (176.30 g plant-1) were obtained from combined application of 150 kg ha-1 NPS + 69 kg ha-1 N rates. The highest number of primary branches plant-1(12.63), dry leaf weight (43.93 g plant-1) and aboveground dry biomass (4.64-ton ha-1) were obtained from combined application of 100 kg ha-1 NPS + 69 kg ha-1 N, whereas the highest essential oil yield (30.22 kg ha-1) was due to combination of 100 kg ha-1 NPS + 46 kg ha-1 N rate and it is statistically at par with 50 kg ha-1 NPS + 46 kg ha-1 N. Therefore, combined application of 50 kg ha-1 NPS + 46 kg ha-1 N would be suggested in case of basil used for extracting essential oil.

Biomass yield and polyphenol compounds profile in globe artichoke as affected by irrigation frequency and drying temperature

Globe artichoke [Cynara cardunculus var. scolymus (L.) Fiori] is a proven source of nutraceutical compounds with high bioavailability. However, different pre- and post-harvest variables may affect plant secondary metabolism. In this view, the present study investigated the influence of irrigation frequency and drying temperature on the yield of dry leaf biomass and its pharmacological value in terms of polyphenol content. The field treatments included three irrigation frequencies (7, 14 and 21-day intervals) with a single dose of 10 mm water, and control (not irrigated). Artichoke biomass leaves were collected from 120-day plants and dehydrated using different air temperatures (30 °C, 40 °C, and 50 °C). The samples were analyzed for polyphenolic compounds by HPLC method. Antioxidant activity was also studied by ABTS, DPPH, and FRAP assays. Irrigation frequency significantly influenced the yield of dry leaf biomass with a greater increase in the case of irrigation frequency every 7 and 14 days than every 21 days. The content of caffeoylquinic acids (TCQA) was higher under soil water deficit conditions than in the raw material obtained from plants irrigated with different frequencies. The drought stress caused by the lack of additional irrigation increased the content of chlorogenic and ferulic acids in the biomass leaves. Higher drying temperatures (40 and 50 °C) increased the content of cynarine by 100% and 132% and ferulic acid by 100% and 172%, respectively, compared to biomass leaves dried at 30 °C. Irrigation frequency influenced the content of flavonoids, and frequency every 7 and 14 days than 21 days reduced apigenin and increased luteolin content. A high correlation between the content of TCQA and the frequency of irrigation and drying temperature was reported.

OBTAINING OF PLANT TISSUE CULTURE Scutellaria baicalensis GEORGI. AND ITS BIOCHEMICAL ANALYSIS

Aim. To obtain a plant tissue culture of S. baicalensis as a possible source of biologically active compounds (BAC) with a wide range of pharmacological action. Methods. Plant tissue culture, photocolorimetric method, reversed-phase high performance liquid chromatography (HPLC) method. Results. Two stably productive plant tissue culture strains (16SB3 and 20SB4) of S. baicalensis were obtained from fragments of roots seedling on a specially developed agar nutrient medium 5С01. The yield of dry biomass from 1 liter of this medium per passage (21st day of growth) for strain 16SB3 is 25–30 g, for strain 20SB4 – 30–40 g. The total content of flavonoids in dry biomass was in terms of routine for strains 16SB3 and 20SB4 – 0.6–0.9 and 0.7–0.9 mg/g, respectively, and the yield of flavonoids – 18–27 and 21–36 mg/l of nutrient medium, respectively. BAC typical for plants in nature, in particular, flavonoids vogonin, baikalein, neobaikalein, skulkapfavon and their derivatives, were found in the studied biomass of both strains. Conclusions. It was found that the biomass of the two strains of S. baicalensis plant tissue culture accumulated the same BAC, in particular, flavonoids, as do plants in natural conditions. The resulting plant tissue culture is promising as a possible source of Baikal skullcap BAC.

The Admont Grassland Experiment: 70 years of fertilizer application and its effects on soil and vegetation properties in an alluvial meadow managed under a three-cut regime

Fertilizer application is a widely used management technique for increasing forage production from agricultural grassland. Fertilization is also a key driver of changes in soil nutrient status and plant species composition of grassland as shown in many short-term studies. Results from long-term experiments can further improve understanding of plant-soil relationships and help with management recommendations for agricultural and environmental outcomes. We collected data from a long-term experiment on alluvial meadow (Admont Grassland Experiment, Austria; established 1946) with 24 fertilization treatments managed under a three-cut regime. Soil sampling in autumn 2015 and vegetation sampling in spring 2016 were conducted in seven selected treatments. Combinations of N (nitrogen 80 kg ha−1), P (phosphorus 35 kg ha−1) and K (potassium 100 kg ha−1) were applied annually and compared with a non-fertilized control. Treatments were: Control, N, P, K, NP, NK, PK and NPK fertilization.Long-term different fertilization affected soil pH and nutrient concentrations in the soil and plant species composition, but no significant effects on species richness were found. Short species (<0.5 m height) prevailed in all treatments regardless of nutrient application, probably as a result of the three-cut defoliation. The dry matter biomass (DMB) yield in the Control was limited by N and P and synergisticly co-limited by N, P and K, and DMB yields of more than 5 t ha−1 per year were achieved under nutrient combinations containing P (NP, PK, NPK) without loss of species richness.Results from the Admont Grassland Experiment show that the tested nutrient combinations significantly increased DMB yield and changed the species composition, but without significant effects on species richness. Long-term biomass yields of more than 5 t ha−1 DMB per year can be achieved with any nutrient combination containing P without loss species richness in an alluvial meadow managed under a three-cut regime.

Quantitative and population genomics suggest a broad role of stay-green loci in the drought adaptation of sorghum.

Drought is a major constraint on plant productivity globally. Sorghum [Sorghum bicolor (L.) Moench] landraces have evolved in drought-prone regions, but the genetics of their adaptation is poorly understood. Here we sought to identify novel drought-tolerance loci and test hypotheses on the role of known loci including those underlying stay-green (Stg) postflowering drought tolerance. We phenotyped 590 diverse sorghum accessions from West Africa in 10 environments, under field-based managed drought stress [preflowering water stress (WS1), postflowering water stress (WS2), and well-watered (WW)] and rainfed (RF) conditions over 4 yr. Days to 50% flowering (DFLo), aboveground dry biomass (DBM), plant height (PH), and plant grain yield components (including grain weight [GrW], panicle weight [PW] and grain number [GrN] per plant, and 1000-grain weight [TGrW]) were measured, and genome-wide association studies (GWAS) was conducted. Broad-sense heritability for biomass and plant grain yield was high (33-92%) across environments. There was a significant correlation between stress tolerance index (STI) for GrW per plant across WS1 and WS2. Genome-wide association studies revealed that SbZfl1 and SbCN12, orthologs of maize (Zea mays L.) flowering genes, likely underlie flowering time variation under these conditions. Genome-wide association studies further identified associations (n = 134; common between two GWAS models) for STI and drought effects on plant yield components including 16 putative pleiotropic associations. Thirty of the associations colocalized with Stg1, Stg2, Stg3, and Stg4 loci and had large effects. Seven lead associations, including some within Stg1, overlapped with positive selection outliers. Our findings reveal previously undescribed natural genetic variation for drought-tolerance-related traits and suggest a broad role of Stg loci in drought adaptation of sorghum.

Response of Mung Bean Varieties (Vigna radiata L.) to Application Rates and Methods of Blended NPS Fertilizer at Humbo

Mung bean is among the important dry-land legumes in the country and in the study area. However, the productivity of the crop is constrained by biotic and abiotic factors, mainly poor soil fertility, lack of adaptable varieties, and peer agronomic practices. Field trial was initiated at Humbo District with the objective of investigating the rate of NPS-blended fertilizer and application methods on overall performance of mung bean (Vigna radiata L.) varieties. The treatments comprised factorial combination of four rates of NPS (0, 50, 100, and 150 kg ha−1), two types of application methods (broadcasting and drilling), and two mung bean varieties (Shewa Robit and N-26) laid out in RCBD with three replications. Analysis of variance revealed that NPS rates and varieties significantly affected phenology and yield components. Application methods affected yield and thousand-seed weight. Two-way interaction of NPS rates with varieties significantly influenced plant height and pod plant−1. Three-way interactions also significantly influenced aboveground dry biomass and grain yield. The greatest dry biomass (4273.7 kg ha−1) and grain yield (1539.2 kg ha−1) were produced by N-26 variety with fertilizer composed of NPS at 150 kg ha−1 using the drill application method. Partial budget analysis also revealed that the highest (ETB 46,934.4 ha−1) net benefit was obtained at 100 kg NPS ha−1 with variety N-26 from the drilled method. Hence, growing N-26 with 100 kg NPS ha−1 applied using the drilling method of fertilizer application was found as the most suitable treatment combination to improve the income of farmers and increase productivity of mung bean.