Onion Plants Research Articles

Daya Hambat Perasan Bawang Dayak (Eleutherine Palmifolia (L.) Merr) Terhadap Pertumbuhan Bakteri Stapylococcus aureus Metode Difusi

Traditional medicine is an ingredient that can be derived from plants, animals, minerals, preparations of extract (galenic) or a mixture of these materials which have been used for generations for treatment. The use of medicinal plants as traditional medicine has many advantages. It is easy to obtain because the raw materials can be grown and mixed by yourself, so it is cheaper. People also consider traditional medicine to be safer than chemical drugs because the side effects are relatively smaller.One of the plants that have been used as traditional medicine is the Dayak onion. Dayak onion (Eleutherine americana L. Merr) is empirically used by local people in Kalimantan as a traditional medicinal plant. Dayak onions can be used as raw materials for medicine because they contain active compounds in the form of alkaloids, glycosides, flavonoids, phenolics, triterpenoids or steroids and anthraquinones which have been known as medicinal raw materials. Until now, the Dayak onion plant is used for the treatment of colon cancer, breast cancer, diabetes mellitus, hypertension, lowering cholesterol, stroke, stomach pain medication after childbirth and ulcer medicine.This study aims to determine the inhibition of Dayak onion (Eleutherine americana L. Merr) on the growth of Stapylococcus aureus bacteria by diffusion method. The research design was a quasi-experimental. The population of Dayak onion bulbs. As a sample of Dayak onion bulbs made in concentrations of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100%. With the formula of Randomized Block Design (RAK), 30 samples were obtained. Antimicrobial testing using the diffusion method.The results obtained were resistant at a concentration of 10% - 60% (inhibition zone < 9 mm) and a concentration of 70-90% intermediate (inhibition zone 10-11) and a concentration of 100% sensitive (inhibition zone > 12). After being analyzed statistically using the Kruskal-Wallis test, a significant asymp value was obtained. sig = 0.001 < 0.050. It was concluded that there was an effect of the juice of the Dayak onion (Eleutherine palmifolia (L.) Merr) in inhibiting the growth of Stapylococcus aureus bacteria.

First Report of Colletotrichum circinans Causing Anthracnose in Allium fistulosum var. giganteum in Gansu Province, China.

In September 2018, severe symptoms and high incidence (about 60%) of an onion anthracnose disease attributable to infection by Colletotrichum spp. was observed in production fields of Dingxi city, Gansu Province, China. The mature onion plants near to harvest (Allium fistulosum L. var. giganteum Makino) expressing necrotic symptoms had oval lesions with dark spots that were made up of stromatic masses that had formed beneath the cuticle of the plant base. Twenty symptomatic plants were sampled. Symptomatic tissues were surface sterilized with sodium hypochlorite, transferred aseptically to 20 mL potato dextrose agar in a petri plate and incubated at 30 ± 2 °C. After seven days, cultures produced acervuli and setae, a characteristic sign of Colletotrichum spp. Acervuli were observed with a black, bulbous base and acicular setae while conidia were elliptical (14-25 x 3-6 µm), unicellular hyaline and slightly falcate (Figure 1). DNA was extracted from a 7-day old culture and the ITS region was amplified using primers D1 (5'-GCATATCAATAAGCGGAGGAAAAG-3') and D2 (5'-GGTCCGTGTTTCAAGACGG-3') (Kurtzman and Robnett, 1997). The resulting sequence (548 bp) was deposited with NCBI GeneBank under accession number MW127281. The fungus was confirmed as Colletotrichum circinans after conducting a BLAST search with the ITS sequence that reported a highest homology (99% similarity) with MH81329.1 (C. circinans). The speciation was further confirmed by amplifying regions of the TUB2, GAPDH, and ACT genes using primers given in Table S1 and sequences were also submitted to NCBI GeneBank under accession numbers MZ456033, MZ456032 and MZ456031, respectively. The subsequent BLAST results for these three additional gene regions were consistent with the results of the ITS region and fungus was identified as C. circinans. The isolated pathogen was tested for its pathogenicity on onion plants (Allium fistulosum L. var. giganteum Makino). A conidial suspension 30 ml (5 × 105 conidia/ml) was mixed with 1 kg sterilized potted soil in 15 cm diameter plastic pots. Un-inoculated, sterilized soil was used as control. Three green onion plants per pot were planted (Figure S2). The experiment was repeated three times with 15 replications in each experiment. Plants were maintained for 120 days under greenhouse conditions and were monitored for the development of anthracnose symptoms. Symptoms recorded previously on onion plants in field (i.e. necrosis, sunken oval lesions and dark spots) were observed after 30 days on plants grown in inoculated soil while control plants remained asymptomatic (Figure S1). Three samples from symptomatic tissues of each plant were used for re-isolation of the pathogen on PDA, as described above. Cultures grown on PDA were confirmed both on a morphological and molecular basis as Colletotrichum circinans.These morphological, molecular, and pathogenicity tests of the isolated fungus confirm that the anthracnose symptoms observed on onion in Gansu Province, Beijing, China was caused by Colletotrichum circinans. Six different Colletotrichum spp. have been reported to cause diseases on onion worldwide (Rodriguez et al. 2012). C. circinans, which causes smudge, is an occasional onion pathogen was previously recorded as C. dematium (Pers.) Grove f. circinans Arx, which is specific to Allium spp. (von Arx 1970; von Arx 1981). However, Sutton (1992) described C. circinans as a distinct species from C. dematium. The fungus causes smudge or leaf spot of Allium spp. (Farr et al. 1989) and has been reported from Korea, Japan, Argentina, India, the UK and most other regions of the world (Cho & Shin 2004; Kiehr et al. 2012). Smudge may be a disease of concern post-harvest as fungal growth compromises the onion scales and bulb (Walker 1921). In China, this is the first report of C. circinans causing anthracnose in Allium fistulosum L. var. giganteum Makino in Gansu Province.

Effect of potassium fulvate and organic nitrogen rates on growth, yield and nutritional status of onion plants grown in sandy soil

Two field experiments were conducted during 2019/2020 and 2020/2021 growing seasons at the National Research Centre Experimental farm at El-Nubaria, El-Behira Governorate. The aim of the research was to study the effect of potassium fulvate and organic nitrogen on the growth, yield and nutritional status of onion plants grown in sandy soil. The factorial experiment was consisting of 12 treatments with four replicates. The experiment was arranged in split plot design. Four levels of K-fulvat (10% K2O) (0, 25, 50 and 75 kg/fed.) were occupied at the main plots and the three concentrations of organic nitrogen (15 % N) (0, 1, 2 cm/l) were randomly allocated in the sub plots. The results indicated to increase in spraying the concentrations of organic nitrogen from 0 to 2 cml-1 with the addition of different rates of potassium fulvate, the growth and yield parameters of onion plants increased significantly and morally during the two successive growing seasons. The best experimental treatments were which gave the highest yield and quality of onion bulbs when spraying the highest concentration of organic nitrogen (2 cml-1) with the highest addition of potassium fulvate (75 kg fed-1), during the two successive growing seasons.

Comparison of Yield and Yield Components of Several Crops Grown under Agro-Photovoltaic System in Korea

Renewable energy generation has attracted growing interest globally. The agro-photovoltaic (APV) system is a new alternative to conventional photovoltaic power plants, which can simultaneously generate renewable energy and increase agricultural productivity by the use of solar panels on the same farmland. The optimization of crop yields and assessment of their environmental sensitivity under the solar panels have not yet been evaluated with various crop species. This study aimed to evaluate the agronomic performances and crop yields under the APV system and the open field with crop species such as rice, onion, garlic, rye, soybean, adzuki bean, monocropping corn, and mixed planting of corn with soybean in South Korea. The results indicated that there was statistically no negative impact of the APV system on the forage yield of rye and corn over two years, suggesting that forage crops under the APV system were suitable to producing forage yield for livestock. In addition, the measured forage quality of rye was not significantly different between the open field and the APV system. However, rice yield was statistically reduced under the APV system. The yield of legume crops and vegetables in this study did not show consistent statistical results in two years. For further study, crop yield trials will still be required for rice, soybean, adzuki bean, onion, and garlic for multiple years under the APV system.

Yield and Morphophysiology of Onion Grown under Salinity and Fertilization with Silicon

Salinity limits agricultural yield in the arid and semi-arid regions of the world. Silicon (Si) benefits plants under abiotic stresses. However, Si fertilization in the yield of onion plants under salt stress are less well known. We conducted a field experiment to evaluate Si fertilization in onion yield, physiology and postharvest quality irrigated with saline water. The experiment was designed in randomized complete blocks, with four replicates, and treatments were arranged in split plots. The plots had four water electrical conductivity (0.65, 1.7, 2.8 and 4.1 dS m−1) and the subplots had five Si levels (0, 41.6, 83.2, 124.8 and 166.4 kg ha−1 of Si), in the form a diatomaceous earth-based fertilizer derived from the species Melosira granulata. Waters high salinity reduced onion yield and bulb fresh mass, and increasing small bulbs (<50 mm) production. Waters high salinity hampered onion plants membrane instability index, relative water content and contents of total chlorophyll, and carotenoids. Waters high salinity too hampered onion firmness, pH, soluble solids concentration, and SS/TA ratio. Si fertilization increased onion yield, bulb fresh mass and production of large bulbs (≥ 50 mm), and saline stress attenuation occurred up to 2.8 dS m−1. Si fertilization improved onion plants chlorophylls, carotenoids, total sugars, soluble solids, ascorbic acid, and pyruvic acids content. Si fertilization promoted onions acclimatization to salt stress, because increasing the synthesis of soluble sugars, ascorbic acids, and thio-compounds identifiable in PyA. Therefore, we recommend 78.5 kg ha−1 of Si for onion plants under saline stress conditions.

Effect of Some Growth Stimulants and Different Levels of Potassium and Biofertilizer on Growth Aspects, Bulb Yield and Quality Attributes of Onion (Allium cepa L.)

Onion (Allium cepa L.) is the most widely cultivated species of the Allium genus. Onion is rich in many vital nutrients and sulfur (S)-containing several compounds important for human health. Recently, Allium species requirements have gained special attention in this special time due to its export importance. The aim of this study is to compare the effects of the recommended dose of potassium (100% KRD) against three lower levels of potassium mixed with Bacillus circulans, potassium solubilizing bacteria (80% KRD+biofertilizer, 60% KRD+biofertilizer or 40% KRD+ biofertilizer, as well as foliar applications of copper (Cu), boron (B) or putrescine (Put) that have great impacts on yield, quality and onion attributes.The highest level of potassium (100% KRD) resulted in the highest growth parameters and the richest leaves content in N, P, K, S, B, Cu, and carbohydrates, yield, as well as the best quality parameters of bulbs. All growth and yield parameters decreased gradually with reducing the levels of K fertilization. Foliar spraying of Cu, B, and Put combined with all different levels of K fertilizer improved all plant parameters. The highest impact on plant growth was due to Put followed by B at all levels of soil fertilization. Plants that were exogenously sprayed with Put and B exhibited an increase in N, P, K, B, and carbohydrates under different levels of fertilizers, while foliar application with Cu highly increased S and Cu in onion leaves with all levels of K fertilization. The combined treatment of B and all different levels of K fertilizer considerably improved all yield measurements, except with allyl propyl disulfide, which estimated a highly significant increase with Put foliar application coupled with 40% KRD+Bio. In a nutshell, exogenous Put, B, and Cu foliar applications on onion plants increased bulb yield and its quality attributes with the recommended level of potassium or lower recommended levels of K mixed with biofertilizer.

Potential of Kirinyuh (Chromolaena odorata) and Cow Manure for Available Phosphor Supply on Sandy Beach Soil and P Uptake by Onion (Allium cepa L.)

Abstract The low availability of phosphorus nutrients for onion plants resulted in disruption of the plant growth process such as blocking the extension of the root causing the uptake of nutrients decreased. This research was conducted to know the role of Kirinyuh (Chromolaena odorata) and cow manure for available phosphor of Sandy Beach Soil and P uptake by onion. The research method used was the Completely Randomized Design Method of 15 treatments, namely the mixture treatment of cow manure (S) and kirinyuh (K) at 10, 20 and 30 tons/ha equivalent doses. The treatment was: the dose of S and K mixture at without cow manure and kirinyuh (P0), 10 ton/ha comprised S/K ratios of 100/0 (P1), 75/25 (P2), 50/50 (P3), 25/75 (P4), 0/100 (P5); at 20 ton/ha comprised S/K ratios of 100/0 (P6), 75/25 (P7), 50/50 (P8), 25/75 (P9), 0/100 (P10); and at 30 ton/ha comprised S/K ratios of 100/0 (P11), 75/25 (P12), 50/50 (P13), 25/75 (P14), 0/100 (P15). Each treatment was repeated 3 (three) times. The results were analyzed by variance at 5% significant level and tested further with Duncan Multiple Range Test at 5% level if there was a significant influence. The results showed that the mixture of cow manure and kirinyuh could increase P available of Sandy Beach Soil and P uptake of onion. Giving a mixture of cow manure (S) 25% and kirinyuh (K) 75% at the equivalent dosage of 30 tons/ha significantly gave the higestes P available of Sandy Beach Soil and P uptake of onion.

The effects of timing, scheme, planting depth and size of the uterine bulbs on the productivity of seed plants and seed quality onions in the conditions of the Foothill zone of the North Caucasus

Relevance. Onion is a valuable food crop, which is due to its chemical composition, taste and medicinal qualities. As part of the strategy to ensure food security and independence of Russia in the agricultural sector, it is necessary to increase the production of vegetable products, including onions, and for this it is necessary to increase the production of domestic seeds. Seed production is an important branch of agriculture, which consists in the planned reproduction of zoned varieties. Unlike commodity production, it is a more labor-intensive industry and requires regular improvement of existing technologies that take into account the specifics of new varieties and hybrids.Materials and methods. The object is onion (Allium сера L.). Research material: new varieties of spring onion Primo and Ampex of selection of FSBSI FSVC. The studies were conducted in 2018-2020 on the basis of the North Caucasus branch of the FSBSI FSVC. Laboratory and field experiments were carried out according to generally accepted methods. The area of the accounting plot is 5m2 , the repetition is 4-fold, with a randomized arrangement of options.Results and discussions. Different planting dates of uterine bulbs, their diameter, standing density, planting depth, significantly affected the qualitative and quantitative indicators of seed productivity of onion plants of Primo and Ampex varieties. The results obtained made it possible to modify and optimize individual elements of varietal technologies of onion seed production. To create the best conditions for the growth and development of seed plants of Ampex and Primo varieties and to obtain high yields of high-quality seeds in the conditions of the foothill zone of the North Caucasus, it is recommended to: use queen bulbs of 8 cm in size, organize the planting of queen bulbs in the first decade of November, use a scheme for planting queen onions: 75x10 cm, use a planting depth of 15 cm. With this technology, the productivity of plant seeds reaches 6-8 g in the Ampex variety and 5-7 g in the Primo variety, and the yield of conditioned seeds is 520-580 kg/ha and 450-600 kg/ha, respectively.

Microalga Biofertilizer Triggers Metabolic Changes Improving Onion Growth and Yield

Seeking the development of nature-friendly agronomic techniques, the use of natural sources to promote plant growth and increase agricultural yield has gained relevance. In this context, the use of biofertilizers or biostimulants obtained from microalgae has been studied, as these microorganisms have in their composition a great diversity of bioactive molecules. This study aimed to evaluate the effect of microalga Asterarcys quadricellulare (CCAP 294/1) on organic onion production, verifying its action on metabolism, growth and yield of two cultivars. Thus, two experiments were carried out: (i) foliar applications on onion plants grown in pots in a greenhouse; (ii) foliar applications on field-grown onion under an organic system. Both experiments were undertaken using solutions with spray-dried microalga biomass at concentrations of 0.05, 0.15, 0.25 and 0.4 g L−1. Biometric variables, yield of bulbs and biochemical variables were evaluated indicating that the use of A. quadricellulare promoted plant growth and increases in bulb caliber and yield of both onion cultivars. The microalga biomass stimulated plant metabolism by increases in contents of chlorophyll, carotenoids, amino acids, and the nitrate reductase enzyme activity in leaves, also free amino acids and total sugar contents in bulbs, highlighting the biomass concentration of 0.25 g L−1.

Combined use of compost, compost tea, and vermicompost tea improves soil properties, and growth, yield, and quality of (Allium cepa L.)

Liquid organic fertilizers are organic solutions that are a valuable choice for sustainable agriculture. In addition, these organic forms play a significant role, in integrated waste management strategies. In this study, a one-way analysis of variance, Pearson correlations and principal component analysis were performed on all traits, to compare the responses of sole application of compost, compost tea, vermicompost tea and their combinations on growth, yield of Allium cepa and on soil properties. The results showed that, in most cases with fertilizers treatments, the soil pH, CaCO3 and bulk density were decreased, while soil organic matter, total N, available P and K were increased. A mixture of 50% compost, 25% compost tea, and 25% vermicompost had more desirable effect on plant height, leaves number, plant fresh weight and plant dry weight. Therefore, application of 50% compost tea and 50% vermicompost tea, it is possible to achieve an acceptable total bulb yield ton/ha, total soluble solids %, and dry matter %. While, available P, K in soil and P % in plant were raised when plants treated with teas sole or combined with compost 50%. Using a mixture of 50% compost, 25% compost tea, and 25% vermicompost tea, was a higher nutrient concentration and had a significant impact on onion plants productivity, and on soil properties.

Genotoxicity evaluation of paper industry wastewater prior and post-treatment with laccase producing Pseudomonas putida MTCC 7525

Paper industry wastewater is considered a severe polluter of the environment because it contains various toxic pollutants that critically impact the aquatic and terrestrial ecosystems. The current study aimed to assess the bioremediation perspective of Pseudomonas putida strain to eliminate the hazardous pollutants of paper industry wastewater. The physico-chemical analysis of the treated wastewater showed that the Pseudomonas putida MTCC 7525, which secreted laccase enzyme, significantly reduced the pollution parameters such as EC, TDS, COD, phenols, TKN, TOC, lignin and color by 69, 87, 68, 97, 75, 85, 57 and 72%, respectively in comparison to the control. The organic pollutants in the wastewater samples were characterized and identified by GC-MS and FTIR analysis, which also showed that most of the toxic compounds were reduced following the bacterial treatment. The toxicity assessment of the wastewater was performed in terms of cyto-genotoxicity and phytotoxicity assay using onion and mung bean plants. The result of the toxicity study demonstrated that the toxic effect of the wastewater samples declined after the bacterial treatment. These results showed that Pseudomonas putida MTCC 7525 could be used effectively in the paper industry for bioremediation applications, thus minimizing the undesirable effects on the environment.

Onion Germplasm Possesses Lower Early Season Thrips Numbers

Onion is one of the most valuable vegetable crops in the US. Onion thrips were identified as one of the main threats to the US onion industry. An integrated approach, including host plant tolerance, is required. For this study, four New Mexico State University breeding lines, along with two thrips-attractive cultivars, were evaluated for their attractiveness to thrips. In addition, this study observed thrips population dynamics throughout the growing season and the relationship between onion plant size and thrips attractiveness. The experiment was designed as a randomized complete block design with three blocks, each containing four replications. Thrips-infested bulbs were used to ensure the presence of thrips and thrips-attractive plants were used to ensure equal thrips distribution throughout the field. Ten plants were randomly selected from each plot and thrips and leaf numbers were counted multiple times through the growing season. Plants of NMSU breeding lines were observed to have fewer thrips, be more tolerant to thrips pressure and produce more leaves and larger bulbs than thrips-attractive entries. Early in the growing season, leaf number was not a determining factor in thrips population dynamics. The larger bulb weights of the breeding lines allowed them to maintain their market value. A delay in thrips population buildup in plants of the breeding lines may result in the critical threshold for spraying for thrips being reached later in these lines. This would potentially allow for fewer pesticide applications by growers, increasing growers’ profits and ensuring a more environmentally friendly approach to plant production.

Analisis Molecular Docking Senyawa dari Jamur Endofit Bawang Dayak (Eleutherine bulbosa) Sebagai Inhibitor Lipase Pankreas

Nowadays some efforts are being made to reduce obesity by using drugs that aim to reduce appetite of the drug users. However, the use of drugs still has harmful side effects. Endophytic fungi originating from the Dayak onion plant are thought to have secondary metabolites that have potential as anti-obesity. The aims of this study were to determine the compounds produced by endophytic fungi of Dayak onion and to determine the potential components as inhibitors of pancreatic lipase enzymes. Samples of Dayak onions were collected from Palangka Raya using purposive sampling method. Isolation of endophytic fungi was conducted using surface sterilization method and the isolates were grown on PDA. Isolates were characterized and fermented on PDB for 14 days. The selected isolate was analyzed by using GCMS then molecular docking was performed using Autodock Vina and PyRx. The research results showed that there were 7 isolates of endophytic fungi isolated from leaves and roots tissues of Dayak onion. GCMS analysis showed that EBD1 contains 38 compounds. Molecular docking analysis showed that 1,3-Di-O-Acetylpentopyranose, a test ligand, has the closest binding affinity value (-6.6 kcal/mol) to orlistat (control) (-6.8 kcal/mol). Thus, it has the potential as an inhibitor of pancreatic lipase enzyme protein.

Characterization of Alternaria porri causing onion purple blotch and its antifungal compound magnolol identified from Caryodaphnopsis baviensis.

Alternaria porri (Ellis) Clf. causes purple blotch disease on Allium plants which results in the reduction of crop yields and quality. In this study, to efficiently find natural antifungal compounds against A. porri, we optimized the culture condition for the spore production of A. porri and the disease development condition for an in vivo antifungal assay. From tested plant materials, the methanol extracts derived from ten plant species belonging to the families Cupressaceae, Fabaceae, Dipterocarpaceae, Apocynaceae, Lauraceae, and Melastomataceae were selected as potent antifungal agents against A. porri. In particular, the methanol extract of Caryodaphnopsis baviensis (Lec.) A.-Shaw completely inhibited the growth of A. porri at a concentration of 111 μg/ml. Based on chromatographic and spectroscopic analyses, a neolignan compound magnolol was identified as the antifungal compound of the C. baviensis methanol extract. Magnolol showed a significant inhibitory activity against the spore germination and mycelial growth of A. porri with IC50 values of 4.5 and 5.4 μg/ml, respectively. Furthermore, when magnolol was sprayed onto onion plants at a concentration of 500 μg/ml, it showed more than an 80% disease control efficacy for the purple blotch diseases. In terms of the antifungal mechanism of magnolol, we explored the in vitro inhibitory activity on individual oxidative phosphorylation complexes I–V, and the results showed that magnolol acts as multiple inhibitors of complexes I–V. Taken together, our results provide new insight into the potential of magnolol as an active ingredient with antifungal inhibitory action to control purple blotch on onions.

Influence of PGPR, AM Fungi and Conventional Chemical Fertilizers Armament on Growth, Yield Quality, Nutrient’s translocations and Quercetin Content in Onion Crop Cultivated in Semi-Arid Region of India

The rhizosphere is the thin region of the soil that is directly affected by secretion from the roots and the microbes accompanying the soil, known as the root microbiome. The rhizosphere involving the pores of the soil includes many beneficial bacteria and other diverse microorganisms. The field experiment was conducted during the Kharif season at the Lasalgaon taluka of Nashik district farmers’ field, Maharashtra, India, to determine the influence of biofertilizers on onion. To study the effect of five combinations of biofertilizers compared with the recommended rate of chemical fertilizers on cash crop onion cv. Nashik Red. The treatments were control (100% RRF), Azotobacter + AM fungi, Azospirillum + AM fungi, Azotobacter + Azospirillum, Azotobacter + Azospirillum + AM fungi and Bio consortium (NPK) + Azospirillum + AM fungi. Height (64.24 ± 3.22 cm) and the number of leaves (13.58 ± 3.12) of the plant was maximum with the application of the consortium (NPK) + Azospirillum + AM fungi. The maximum leaf area (84.45 ± 2.44 cm2) was recorded in T6 and the minimum in T4 (82.45 ± 2.25). Different doses of onion plants inoculated with biofertilizers showed a significant increase in quality parameters such as neck thickness (1.12 ± 0.22cm), bulb diameter (14.45 ± 0.53cm), bulb size index (19.45 to ± 0.51 cm2), bulb weight (68.15 ± 2.27g), bulb length (6.21 to ± 1.48 cm), bulb scale (11.23 ± 1.23) was maximum in the consortium (NPK) + Azospirillum + AM fungi treated onion. Biofertilizers such as consortium treatments such as consortium (NPK) + Azospirillum + AM fungi resulted in a better morphological character, quality yield, TSS, starch, reduction sugar, quercetin contents among root colonization of mycorrhizae compared to the uninoculated control (100% RRF). The consortium (NPK) + Azospirillum + AM fungi and 100% RRF provided a maximum bulb length of 6.21 ± 1.48cm and 6.12 ± 1.59cm, respectively. The maximum number of scales per bulb (11.23 ± 1.23) was counted by the consortium (NPK) + Azospirillum + AM fungi. Plants treated with the consortium (NPK) + Azospirillum + AM fungi produced the maximum bulb weight (68.15 ± 2.27g) and the minimum (64.23 ± 2.39 g) in Azotobacter + Azospirillum. The maximum TSS (13.354 %) was noticed in T6 and the minimum in T3. The maximum percentage of starch (6.65%) and the highest percentage of reducing sugars (1.98%) were detected by Azotobacter + Azospirillum + AM fungi. Total pooled weight loss (%) up to 60 days was found to be minimal (11.87%) by Azotobacter + AM fungi followed by Azotobacter + Azospirillum (14.40%). The maximum colonization of mycorrhizae (79.9%) was recorded in the consortium (NPK) + Azospirillum + AM fungi and the minimum in the control (46.67%). It was therefore concluded that the combination of the consortium (NPK bioinoculum) + Azospirillum + AM fungi are improved for onion quality and productivity than the others in terms of sustainable production and environmental consideration.

Anatomical and Biochemical Traits Associated with Field Resistance of Onion Cultivars to Onion Thrips and the Effect of Mechanical Injury on the Level of Biochemical Compounds in Onion Leaves

Thrips tabaci Lind. is a global pest and also represents a serious threat to onion production in Poland. In 2 years (2015–2016) of field studies, 8 onion cultivars were evaluated to characterize the resistance to onion thrips and to determine if any biochemical and anatomical features of onion plants are associated with antixenotic and/or antibiotic mechanisms of resistance. Additionally, the influence of mechanical injury on the content of several biochemical compounds in onion leaves was made. The resistance to thrips colonization during the migration period, abundance, and thrips damage throughout the whole vegetation season was determined. We identified two cultivars, Tęcza and Wenta, resistant to thrips colonization and abundance, and one cultivar Wenta resistant to thrips damage. A positive correlation between concentrations of the reducing sugars and thrips abundance and conversely negative relationships between the total phenolic content and thrips damage was confirmed in both years. We suspect that a thinner epidermal layer, a smaller area of epidermal and mesophilic cells, and a lower diameter of vascular bundles may favor the resistance of onion cultivars to thrips. Thrips foraging resulted in a decrease in the content of soluble sugars, sucrose, and plant pigments in the leaves of all onion varieties.

Rhizospheric Fungus: Morphological Characterization Of Rhizosphere Flower On Onion Plant In Enrekang District

The control of moler disease caused by Fusarium oxysporum on shallot plants in Enrekang Regency still relies on the use of chemical fungicides. Plants that are symbiotic with microbes will produce phytohormones optimally so that it will trigger the tolerance level of plants to abiotic and biotic stresses including plant pathogens, so it is necessary to explore the rhizosphere fungi of onion plants in Enrekang Regency to identify morphologically. This study used a red onion soil rhizosphere soil sample taken at the shallot farming center in Enrekang Regency, isolation and testing were carried out in the plant disease laboratory of Hasanuddin University. The results achieved were 20 isolates with 5 genera of fungi namely Fusarium on isolates 1,2,4,12 and 13, Gliocladium on isolates number 15,

Stability and Hopf bifurcation analysis of a delayed eco-epidemiological model of IYSV disease dynamics in onion plants with nonlinear saturated incidence and logistic growth

Iris Yellow Spot Disease (IYSD), caused by Iris Yellow Spot Virus (IYSV) is a destructive and fastspreading virus disease of onion plants worldwide. It is mainly transmitted by an insect vector called thrips tabaci in a persistent and propagative manner and as such, there is a significant latent time after acquisition of the virus by the vector and an incubation time is needed for the appearance of disease symptoms on plants. In this paper, we formulate and analyze a non-linear mathematical model to explore the dynamics of IYSV disease in onion plants using system of delay differential equations by incorporating incubation and latent periods as time delays factors. The delays are introduced by adding an exposed population for onion plants representing the plants that are infected but not yet infective and by taking into account that there is fraction of the newly exposed onion plants that do not die during incubation period before becoming infective. It is assumed that the onion plant grows logistically in the farm so that the total onion plant population is taken as variable. The local stability of the disease-free equilibrium in the presence of delays is investigated using Descartes’s rule of signs. We establish the sufficient conditions for the stability of the endemic equilibrium in presence of delays and we investigate the occurrence of Hopf bifurcation when certain conditions are satisfied by considering the two delays as bifurcation parameters. We compute the critical values of the delays which preserve the local asymptotic stability of the endemic equilibrium and the model shows an oscillatory behavior beyond these critical values. Finally, numerical simulations are performed and displayed graphically to support the analytical results, and the eco-epidemiological implications of the key outcomes are briefly discussed.

Performance of a nutritional compound on onion plants under the influence of Pfixing bacteria in clay loam soil

Performance of a nutritional compound on onion plants under the influence of Pfixing bacteria in clay loam soil

Influence of seed onion planting time on productivity and quality of bulb onion varieties

Vegetable crops play an important role in human nutrition. They contain the necessary organic acids, mineral salts, vitamins and other useful substances. The most popular among vegetables in the conditions of the Udmurt Republic are white cabbage, carrots and table beets, cucumbers, squash, tomatoes and various types of onions. Among onion crops, leeks and shallots are grown in small quantities; among perennial onions - welsh onions, chives and tree onions. The most common among the population is common onion grown mainly for bulbs, in small quantities - for greens. The study of the planting timing of onion varieties’ seeds is relevant. The studies’ results of the influence of the seed onion planting time on the yield and product quality of common onion varieties in the open ground of the Udmurt Republic are presented. Spicy varieties Stuttgarter Riesen and Shetana were selected for the study. Along with the early spring planting date adopted in Udmurtia, the fall seed onion planting was also studied (September 20, September 30, October 10, October 20). Phenological observations revealed that common onion plants of the standard variety Stuttgarter Riesen entered the leaf lodging and harvesting phases on average three days earlier than the studied variety Shetana. In terms of yield, Stuttgarter Riesen onion surpassed Shetana by 6.8 t/ha (28%) and had a higher content of dry matter, water-soluble sugars and ascorbic acid in the bulbs. Autumn planting dates led to a decrease in all the studied parameters of bulb onion.