Journal of the Saudi Society of Agricultural Sciences最新文献

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.

An initial investigation on the physical traits of the cumin (Cuminum cyminum L.) schizocarps was examined in order to select the best genotypes of cumin grown in three regions of Morocco (Drâa-Tafilalet, Marrackech-Safi, and Oriental). This operation was conducted on 34 cumin accessions from six origins (local, India, Syria, Egypt, Turkey, and Saudi Arabia). To evaluate differences between the physical properties among accessions, length, width, thickness, and both the volumetric mass and the thousand-schizocarp mass were measured. Geometric properties (geometric mean diameter, sphericity index, specific mass and surface area) and gravitational parameters (bulk density, true density, and porosity) were calculated for each accession. Heritability (broad sense), phenotypic and genetic variabilities are also assessed. The average values of the evaluated parameters were found to be significantly different (p < 0.01) between accessions. The physical characteristics of schizocarps were significantly influenced by their origin, cultivated provinces and irrigation methods. Length, width, thickness and length of style range on average from 5.7 to 6.8 mm, 1.5 to 2.5 mm, 1.2 to 1.8 mm and 0.6 to 0.9 mm, respectively. Local and Egyptian accessions were the best-sized accessions. Regarding the weight, the Indian accession C11 registered the best volumetric mass 52.9 g, while the thousand-mass was found to be higher in the local accession from Zagora C19 with 7.3 g. The results showed that the phenotypic coefficient of variation (PCV) was higher than the genotypic coefficient of variation (GCV). The highest PCV and GCV were length of style (30.0%) and true density (24.4%), respectively. Volumetric mass had the highest value of heritability (99%). PCA analysis of seed origin showed clearly the ordination of cumin schizocarps into three groups. The big-sized schizocarps group is composed of local and Egyptian accessions, while the Saudi Arabia accession was individualized in a single group. Regarding the cultivated zone in Morocco, the ordination of schizocarps according to the province revealed four distinct groups. Finally, this study showed that irrigation mode may also affect the physical properties of cumin schizocarps.

Citrus (Citrus spp.), including orange as an important one, has a high economic value and significant role both in global market as well as in Indonesia. However, citrus anthracnose caused by Colletotrichum spp. constantly becomes a limiting factor in citrus production. Nevertheless, there is no report on molecular basis about the species associates to the citrus anthracnose in Indonesia up to date. Therefore, this research aims to identify the isolates of Colletotrichum spp. based on polyphasic approach which combining morphological character, pathogenicity and multigene analysis using actin, β-tubulin, and GAPDH primers. Twenty-two isolates were obtained from leaves and citrus fruits with anthracnose symptoms which showed various morphological characteristics, both macroscopic and microscopic. Pathogenicity test results showed that all 22 isolates were virulent to Keprok Batu 55 orange and California lemon. The anthracnose symptoms produced are identical to the symptoms in the field, however the symptoms on the California lemon were milder than on the Keprok Batu 55 mandarin. The results of multigene analysis showed that there were three species causing citrus anthracnose in Indonesia, which were C. endophytichum, C. queenslandicum, and C. gloeosporioides. Those three species are C. gloeosporioides species complex, and this is the first report of C. endophytichum, C. queenslandicum causing citrus anthracnose in Indonesia which needs further concern for biosecurity. All isolate sequences based on actin, β-tubulin, and GAPDH gene markers were submitted into the GenBank and got accession numbers of OR188855–OR188875.

Mining exploration programmes are being expensive and risky due to the limitations of conventional prospecting methods in identifying desired mineralisation. Worldwide, mining exploration programmes have a success rate of approximately 0.7%. Bio-geochemical methods, a sub-branch of geochemical prospecting, are used to identify potential mineralisation areas by studying the distribution of plants containing certain metals. Turkey's leading position in the world in terms of boron reserves increases the strategic importance of boron. On the other hand, metagenome analysis is an important tool in scientific research for detecting microorganisms. Our study aims to develop a cost-effective and efficient biological alternative method for detecting boron mines. Metagenome analysis output showed correlation with the presence of Calothrix sp. NIES-3974, Snodgrassella alvi, Xanthomonas citri, X. citri pv. Fuscans, Pseudomonas viciae, and Aphanothecaceae bacteria and detecting of the potential boron traces in soil. Modelling studies were also conducted on aquaporin z protein, related to the boron uptake, that can be used for utilising from boron detection.

Integrated agricultural systems (IAS) present a potent solution to address global food shortages by integrating crops, livestock, and forests in a rotational or sequential manner on a single piece of land. This study aims to explore current advances in IAS and their impacts on soil quality improvement. The study also shows the ability of IAS to enhance soil carbon sequestration and mitigate greenhouse gas emissions. Compared to the monoculture systems, the combined production of crops, livestock and forest can improve soil quality attributes including physical properties (aggregate stability, water infiltration, pore distribution and soil water storage), chemical properties (exchangeable bases, base saturation, cation exchange capacity, total nitrogen, available phosphorus, and exchangeable potassium), and biological properties (microbial community and biochemical activities). The enhancement of soil quality due to the adoption of IAS can reduce the dependency on inorganic fertilizer application for increasing global food production. Furthermore, the diverse components in IAS can be harnessed to improve environmental protection by increasing soil carbon storage while limiting the emissions of methane, carbon dioxide and nitrous oxide. Therefore, the adoption of IAS offers the opportunity to sustainably manage soil environment while increasing food production.

Ganoderma boninense, the causative agent behind basal stem rot (BSR) disease in oil palm, instigated a pressing need for innovative and ecologically sustainable strategies to counter its impact. Biological control strategies, particularly employing bio-fungicides, have emerged as environmentally friendly alternatives for managing oil palm plant diseases. This study delved into harnessing the biocontrol potential of Indigenous bacterial isolate by investigating and evaluating its bioactive compounds of ethyl acetate extract with the capacity to suppress G. boninense growth in oil palm plants. Molecular identification was utilized to identify of bacterial isolate using 16S rRNA primers (5′- AGA GTT TGA TCC TGG CTC AG– 3′) and (5′- GGA TAC CTT GTT ACG ACT T– 3′). The agar well diffusion technique and scanning electron microscopy (SEM) were utilized to assess the inhibitory effects of bacterial ethyl acetate extract against G. boninense. A comprehensive analysis of the bacterial ethyl acetate extracts was conducted by gas chromatography - mass spectrometry (GC–MS). Molecular identification confirmed that the bacterial isolate was Bacterium strain BS1727. By employing SEM, the ethyl acetate extracts had influenced on G. boninense mycelial architecture. The exposure to the bacterial ethyl acetate extracts induced degradation and morphological distortion of the mycelial structure, serving as an indicator of its impact on the mycelium's structural modulation. Noteworthy, the spectrum of bioactive compounds was a subset of aromatic hydrocarbons, encompassing volatile organic compounds (VOCs). Based on GC–MS analysis, among the VOCs, acetic acid butyl ester and toluene showed the highest relative peak areas, 46.34 % for acetic acid butyl ester and 31.82 % for toluene, respectively. Ethylbenzene had a relative peak area of 5.4 %, 1,1,2-trichloroethane 4.41 %, and allyldimethyl (prop-1-ynyl) silane 3.17 %. The remaining compounds were 6-undecyl-5,6-dihydro-2H-pyran-2-one, 3-decen-5-one, 2-methyl-, and o-cymene, with the relative peak areas were below 1 %. These findings explained the inherent capacity of antifungal compounds as a viable strategy in inhibiting the growth of G. boninense.

Fluoride is an essential element in preventing tooth decay, but excessive consumption can be harmful to health. There are various sources of fluoride exposure, including oral intake from water, tea, dates, toothpaste, and green vegetables; however, the extent of exposure varies among different groups in the population. Therefore, it is crucial to monitor the consumption of these sources to avoid the risk of excessive fluoride intake. Our study, analyzing 33 varieties of root, fruit, tuber, and leaf vegetables produced in the Rabat-Salé-Kenitra region of Morocco, should be aiming to understand fluoride accumulation in vegetables, classify different varieties based on their fluoride content, and assess the risks associated with high fluoride exposure through vegetable consumption. The results revealed fluoride levels ranging from 2.3 to 36.2 mg/kg for leaves of consumable plants, 0.17 to 13.2 mg/kg for leafy vegetables, 0 to 5.19 mg/kg for fruit vegetables, 1.45 to 3.66 mg/kg for tuber vegetables, 1.62 to 8.33 mg/kg for bulb vegetables, and 0.85 to 3.40 mg/kg for root vegetables. This study emphasizes the significance of understanding fluoride concentrations in vegetables. It suggests classifying different varieties based on their fluoride content to prevent the risks associated with excessive fluoride exposure from consuming these vegetables. High fluoride exposure through vegetables can result in various health problems, including dental, skeletal, and other types of fluorosis.

The use of assisted reproductive technologies to improve productivity in livestock industry is becoming popular. The study aimed to determine the utilisation of artificial insemination (AI) and to find out the factors associated with adoption of AI by beef farmers in selected areas of Southern and Ghanzi districts. The data were collected through a survey where a questionnaire was administered to beef farmers. Random sampling was used to interview 54 beef farmers in Southern district and 40 beef farmers in Ghanzi district. The data were analysed using Frequency procedure in Statistical Package for Social Sciences (SPSS). The association between the nominal variables was tested using Pearson Chi-square in SPSS. There is significant (P < 0.05) association between AI utilization by beef farmers and these socio-economic factors; district where farming is done, age of the farmer, education level, occupation of the farmer, purpose of rearing cattle (commercial or subsistence) and land (communal or ranches). Gender of the farmer is not associated with AI utilization.

Soil carbohydrates play a vital role in maintaining the health of soil and ensuring that ecosystems function properly. The method used in this study for measuring carbohydrate content in soil is quick, effective and easy. The investigation involved using three techniques to extract 45 soil samples of different soil texture; hot water, cool water and classical methods. The extracted samples were then analyzed for carbohydrates using two techniques; the widely accepted Phenol Sulfuric Acid method and the newly developed Sulfuric Acid UV method. The results revealed that the hot water extraction method consistently yielded higher levels of carbohydrates compared to the other methods. Interestingly the newly developed Sulfuric Acid UV method consistently produced similar results to those obtained from the well established Phenol Sulfuric Acid method. These results suggest that the novel Sulfuric Acid UV method, which relies on absorption in the ultraviolet region to analyze soil carbohydrate content is indeed a viable approach. This has allowed scientists and researchers to have an alternative means of determining soil carbohydrate levels.