Journal of the Saudi Society of Agricultural Sciences最新文献

Pesticide toxicity has been a major concern in the recent time. Higher concentrations of pesticides affect the organisms and environmental health. The present study aims to assess the toxicological effect of some commonly used pesticides in southwest Nagaland of India and their impact on the physiology of Phaseolus vulgaris and Pisum sativum along with their correlation to health hazards. The study area is a hilly region where the overall temperature ranges in between 2 °C and 35 °C. The annual rainfall received in the region is between 1000 and 2000 mm. The region shares a subtropical to tropical climate. Agriculture is the main activity of the region. Seeds of Phaseolus vulgaris and Pisum sativum were collected from the local market and sterilized with 2 % sodium hypochlorite for 15 min. The solution of monocrotophos, chlorpyrifos, dimethoate, dichlorvos, and cypermethrin was prepared with 1 ppm, 10 ppm, 50 ppm, and 100 ppm concentrations. The seeds were soaked for 24 h in the test solutions and kept uniformly in sterilized petri dishes in 10 ml of test solutions. For every experiment, three replicates of each sample were taken including the control. The control sample was run with tap water. For each replica 10 seeds were taken, so one sample contained 30 seeds. The seeds of the above two vegetable species were treated with these pesticides and analyzed for germination rate, phytotoxicity, dry biomass, and seedling vigor index. The result has shown the negative impact of higher concentrations of pesticides on plant physiology. A questionnaire and interview-based field survey were also conducted among the users to find out exposure-related health hazards of pesticides. The average time utilized for a single interview was 30 min. According to the self-assessed reports of 323 pesticide users, 17 physical disorders were recorded from the study. Eye irritation (49.12), excessive sweating (46.68), and excessive tiredness were some of the highly observed signs and symptoms among the users. For the statistical analysis, analysis of variance (ANOVA) for the biomass production in radicle and plumule of the studied species was done with OriginPro 8.5 software. A chi-square (χ²) test was performed at the significance level of 5 % for the comparative study among male and female farmers for exposure-related disorders. The correlation analysis was done with MS-EXCEL software. A coefficient correlation value of 0.54 was recorded, which indicates a positive correlation between the studied factors.

Orchard design (intra- and inter-row distance) defines the space allotted to each tree and the light environment for growth in olive hedgerows. Shading between neighboring trees affects the light intensity and quality, modifying the tree vegetative, flowering and fruiting characteristics. In this study, the incident photosynthetically active radiation (PAR) was simulated and the red-to-far-red ratio (R/FR) reflected by neighboring hedgerows down the canopy walls was measured. An analysis is presented of the response of olive vegetative, flowering, fruiting and productive traits to hedgerows of high (HD) and super-high density (SHD) orchards. The study was carried out during the 2018–2019 and 2019–2020 seasons in two 10-year-old olive cv. Genovesa orchards, one in HD (7 x 3.5 m) and the other in SHD (4 x 1.5 m). In both systems, continuous rows were used for measurements of light environment and vegetative, flowering and fruiting characteristics. The R/FR ratio and mean daily horizontal incident PAR were significantly higher in HD than in SHD. One-year-old shoots of HD hedgerows had shorter internodes in L position than U, M and L positions of SHD. Inflorescence number per shoot in the M and L positions of HD were triple than those of corresponding positions of SHD hedgerows. The mean yield per ha for both seasons was similar between HD and SHD hedgerows (average 9.3 and 9.4 t/ha, respectively). A greater planting density in olive hedgerows reduces the R/FR ratio reflected by neighboring trees while reducing incident PAR with increases in the hedgerow height. As a result, more illuminate HD hedgerows have greater specific leaf mass, higher leaf area density and higher axis-order angle compared to SHD hedgerows. This study seeks a new way to understand and measure the suitability of an olive cultivar trained in hedgerows at different planting densities.

The common assessment of soil salinity posits a linear function, which transfers the electrical conductivity (EC) of highly diluted extracts to the standard state of soil paste. Our study examines this assumption and explains its limitations in a wide range of EC for highly saline soils of the Aral region in Uzbekistan. For a comparative EC assessment in the liquid phase from standard soil pastes and 1:5 aqueous extracts we used portable EC–meters. The dependences of EC, total dissolved solids (TDS), and soil–water potential on the pore water content were evaluated using centrifugation to separate the liquid phase from the soil matrix. The non-linearity of the relationship between the EC of water from soil pastes and 1:5 water extracts for both average and median data over a broad (0.4–160 dS/m) range of their variation is detected. A strong retention and concentration of electrolytes in fine pores and water films resistant to vacuum extraction, as well as the nonlinear EC versus TDS relationship in highly saline soils are attributed to this nonlinearity. A comprehensive statistical analysis showed that despite the general non-linearity, in the EC range from 0 to 30–35 dS/m, the results for 1:5 extract can be reliably converted to the standard state using the dilution model for the liquid phase of the soil with one basic parameter of soil bulk density. For hypersaline soils (EC > 30–35 dS/m), conversion based on the dilution theory is unacceptable due to a strong underestimation of TDS.

This study reveals Spatio-temporal prognostication of macro and micronutrients present in entisols, inceptisols and alfisols soil groups at Anaimalai block of Coimbatore district, India through empirical analysis. The soil primary macronutrients and micronutrients for the period 2021–2032 were procured from Autoregressive Integrated Moving Average (ARIMA), Linear Regression (LR) and Logistic Regression (Log R) models by setting out 2005–2020 soil nutrient datasets as input. 1627 soil samples were taken out through composite sampling method in the month of February 2021. The laboratory soil analysis was carried out for macro and micronutrients computation. Computed values were validated with the 2021 soil nutrient empirical models. R² values 0.88, 0.83, 0.85, 0.89, 0.88, 0.92, 0.90, 0.92 and 0.85 for soil pH, EC, Available nitrogen, Available phosphorus, Available potassium, Iron, Manganese, Copper and Zinc respectively divulges the reliability of ARIMA model in forecasting the soil nutrients and are spatially exposed. Spatio-temporal visualization of soil nutrients for a decade with large nutrient database as input along with field validation brings out promising forecasting model that reverberates on futuristic policy making for attaining sustainable agro-productivity.

This study measured the ability of the General Food Security Authority to provide wheat and support for the milling industry and flour production in Saudi Arabia, using econometric analysis. It was found from this study that the General Food Security Authority was able to increase the strategic stock of wheat, by 832.89 thousand tons, until it became sufficient for consumption needs for a period of 5.5 months. The average economic price of flour for local wheat is estimated at about 2884.64 riyals / ton, while it is 2,657.33 riyals / ton for imported wheat. The high economic price of flour in the case of using local wheat is due to raising the price of receiving local wheat to 1700 riyals / ton, especially after the Russian-Ukrainian war. The amount of support for milling companies for local wheat amounted to about 1520 riyals / ton, while it amounted to 1386.04 riyals / ton for imported wheat. The overall value of government support for flour production in 2021 was 5,472.44 million riyals.

This study investigated the morphological response of planted Hypericum perforatum to pedology and climatic conditions in Morocco. In total, 50 fragments detached from the mother stump of H. perforatum were purchased from France and planted in the botanical garden in Meknes 2021–2022. The monitored climatic conditions were temperature (Average (AVT), Minimal (MNT), Maximal (MT), precipitations (PR), and humidity (HD), while the pedology parameters were pH, MO, K, P, MgO, Na₂O, and N. We evaluated the effect of the plant on the microbiology around the roots. The effects of these parameters were tested on the biological parameters, including Diameter of principal stem (DPS), Length of principal stem (LPS), Number of secondary stems (NSS), leaves per plant (NL), and flowers (NF) of H. perforatum during growth. During flowering, LPS and NF were significantly superior in 2022 (67.84 ± 15.91 cm and 300 ± 0.00) compared to 2021 (147.8 ± 8.79 cm and 100.00 ± 0.00). During the vegetative stage, the NSS, NL, and DPS were superior (p < 0.05) in 2022 (10.2 ± 2.59 cm, 78 ± 8.86, and 1.48 ± 0.37 cm, respectively) compared to 2021 (7.20 ± 1.30 cm, 61.20 ± 8.53, 0.92 ± 0.53 cm, respectively). In 2021, vegetative stage was in April, while flowering was in June. In 2022, the vegetative stage was in April, while flowering was in May. In 2021, the pH and OM were similar between T₀ (8.08 and 4.66 %) and T_F (7.96 and 4.46 %) stages, while K, P, and N were significantly decreased in T_F (340.8 mg/kg, 52.81 mg/kg, and 0.229 %) compared to T₀ (369.6 mg/kg, 56.7 mg/kg, and 0.26 %). During T_F of 2022, the pH, N, and OM were similar compared to flowering of 2021, while K, and P were decreased in flowering of 2022 compared to flowering of 2021, while conductivity was increased during flowering of 2022. In contrast, K, MgO, and Na₂O decreased from 2021 to 2022. The fungi and bacteria decreased from 2021 to 2022. In contrast, the density of actinomycetes increased from planting to flowering. Despite the importance of this study, more investigations are needed to confirm the obtained findings and to clarify the effects of cultivation conditions on the phytochemicals of the plant.

Sapota fruits were coated with soyabean starch extracted by two different methods and using three different methods of coating (dipping, spraying, and brushing) to determine their effectiveness starch on edible coating stored under ambient (28 ± 2 °C) and refrigerated (3 ± 1 °C) conditions. The samples based on the above six combinations of starch extraction and method of coating were analyzed for physiochemical changes on fruits at 5-day interval for 25 days. The results revealed that the maximum weight reduction was observed in Ambient Control (AC) and Refrigerated Control (RC) samples as 29.89 % and 17.26 % on the 15th day of storage even though RC sample lasted for 25th day. The value for sugar-acid ratio were found as 28.33 (RDT1), 31.88 (RDT2), 33.40 (RST1), 34.22(RST2), 36.44(RBT1), 36.90 (RBT2), and 51.90(RC) on the 15th day of storage for refrigerated storage and for ambient sample it was found as 12.2, 12.82, 13.08,13.30,13.68 and 13.98, respectively, for ADT1, ADT2, AST1, AST2, ABT1 and ABT2 respectively on the 15th day. The Titratable acidity (TA), Vitamin C, firmness, decay incidence, water activity and colour characteristics exhibited higher values for the sapota fruits treated with soyabean starch as compared to the control samples. The RDT1 sample found better results and enhanced the shelf-life of sapota fruit by 2 weeks in comparison to the control samples (AC&RC) at both storage conditions.

The amendment of salt-affected soils with elemental sulfur (S⁰) has been recognized for its potential to effectively reduce soil salinity and pH, thereby enhancing soil physicochemical properties, promoting crop growth, and improving yields. Despite these known benefits, the widespread adoption of S⁰ for managing saline soils, particularly in arid calcareous regions, remains limited. Consequently, this study aimed to evaluate the impact of S⁰ on salt leaching, soil pH, nutrient uptake, plant growth, microbial diversity, and community structure under alkaline saline soil conditions. The study includes three main experiments: a preliminary column experiment without plants, a field trial with Rhodes grass (Chloris gayana), and a greenhouse pot experiment with wheat (Triticum spp.). Our findings demonstrated that S⁰ incorporation into the soil exerted a positive influence, resulting in increased salt removal, reduced soil pH, and improved plant growth. Specifically, soil amendment with 750 kg S⁰ ha⁻¹ led to a substantial salt removal, exceeding double in the column experiment, approximately 91.3 % in the field trial, and about 34.1 % in the greenhouse pot experiment compared to the control. S⁰ amendment also significantly lowered soil and leachate pH in both field and greenhouse trials, with reductions of 3.3 % and 6.3 %, and 8.1 % and 4.4 %, respectively, relative to the control. Calcium and phosphorus uptake by Rhodes grass increased significantly by 75 % and 14 %, respectively, compared with the control. Soil organic matter content significantly increased from 0.6 % to 1.5 % compared to that of the control. This overall enhancement in soil conditions resulted in a considerable increase in Rhodes grass and wheat yields by 13 % and 59 %, respectively. While the prokaryotic diversity (16S V4 rRNA sequencing) in the Rhodes grass field trial was not significantly affected by S⁰ amendments after two months, the microbial community composition showed remarkable differences between the S⁰-amended and control samples. Eighty-three unique taxa were exclusively found in the S⁰-amended samples. In conclusion, our findings suggest that the amendment of soil with S⁰ is a promising strategy for the sustainable management of calcareous salt-affected soils in arid regions.

In modern or mechanized agriculture, chemical spraying is employed to control weed and prevent pest damage. It is very important to spray the chemicals (herbicides, pesticides, fungicides) very carefully and correctly using suitable tools to control weed and pests while keeping the environmental and health risks at very low level. To achieve this goal, it is necessary to study the effects of different factors on the behavior and movement patterns of sprayed particles from the beginning of the spraying to the end when the particles reach the plant. Therefore, for this purpose, in this study, the effect of three levels of pressure 2, 3 and 4 on the distribution of volumetric volume of fluid particles after exiting from Tee jet nozzles 110-02, 110-03, 110-04 and one newly designed nozzle has been investigated. This was performed by experimental and numerical methods using Computational Fluid Dynamic (CFD) method. The results revealed that the spraying pressure and nozzle type had significant effects on the particles volumetric distribution (p < 0.01). All the treatments differed significantly. The innovative nozzle had the highest spraying performance at all the three pressures compared to the other nozzles. Among the Tee jet nozzles, the nozzle 110-03 has the best distribution of particle frequencies.

Importance of the work

Microorganisms play a pivotal role in the growth and development of plants, making their interaction a promising avenue for managing plant diseases, including those affecting oil palm cultivation.

Objectives

In this study, endophytic microbes such as actinomycetes, bacteria, and fungi were isolated from healthy oil palm tissue in susceptible areas to serve as stock isolates. These isolates underwent in vitro evaluation to determine their efficacy in controlling Ganoderma boninense and to identify bioactive metabolites. Additionally, in planta tests were conducted using bioformulations.

Materials & Methods

A dual culture assay was utilized to assess the inhibitory effects of three different stock isolates on G. boninense. To detect bioactive metabolites responsible for the inhibition, particularly phenazine and syringic acid, a series of procedures involving fermentation, extraction, and LC-MS analysis were employed. Furthermore, the efficacy of bioformulations employing various carriers and consisting of either microbial consortia was meticulously evaluated in a nursery setting. The main focus of this evaluation was to determine their capacity to effectively curb disease onset and maintain the vegetative growth of oil palm during the progression of G. boninense.

Results

Several strains of indigenous bacteria (Pseudomonas aeruginosa strain JQ-41, Serratia marcescens strain S16, Stenotrophomonas rhizophila strain CASMBAUDAL2), an actinobacterium (Streptomyces sp.), and a fungus (Trichoderma sp.) exhibited significant growth inhibition against G. boninense. Based on the results obtained from the LC-MS analysis of the ethyl acetate extract, it was revealed that the extract contains 2 compounds known as antifungal agents, namely phenazine and syringic acid. The most effective approach to mitigate infection involved the preventive application of bioformulations containing mixed bacterial isolates or microbial consortia. After 12 months of observation, these bioformulations demonstrated efficacy comparable to that of Marfu-P, a commercially available biofungicide for oil palm seedlings.

Main finding

The study establishes the effectiveness of endophytic bioformulations as a viable strategy to manage the onset of G. boninense disease, highlighting the potential of microorganisms as an alternative solution for controlling basal stem rot in the nursery.