Rhizopus Research Articles

Multi-Level Characterization of Microbial Consortia Involved in the Biodeterioration of Wooden and Stone Romanian Heritage Churches

The 17th to 19th century wooden and stone churches are an iconic symbol of Romanian national heritage. The present study investigates by qualitative and quantitative methods the microbial communities from the biodeteriorated surfaces of wooden and stone monument churches included in the cultural heritage list of local or national importance. From a total of twelve monuments, samples were taken with cotton sterile swabs, inoculated on specific culture and identified by classical, automated and molecular methods. A total of 133 strains belonging to Ascomycota phylum were identified and confirmed at species level from the wooden churches, amongst which, Penicillium spp. strains (mostly P. corylophylum, P. chrysogenum) were the most frequent, followed by Alternaria alternata and species of Trichoderma, Aspergillus, Rhizopus, Mucor, and Fusarium genera. From the stone churches a total of 100 strains belonging to Aspergillus, Alternaria, Mucor, Penicillium, Aspergillus, Trichoderma, Fusarium and Rhizopus genera were isolated. A total of 55 bacterial strains were isolated and identified as Bacillus, Artrobacter and Pseudomonas species. The microbial load of the samples ranged between 2.18x107 and 3x105 CFU/mL. A very small number of fungal strains (6/77) isolated from wooden churches (mostly A. alternata, followed by P. corylophilum and one Cladosporium spp. strain) and from stone churches (5/55) (mostly A. alternata, followed by A. versicolor, A. nidulans strain) were involved in biofilm formation. The results of this study can help to improve understanding of the microbial deterioration of Romanian heritage churches and allow more reliable decontamination, conservation and preservation tools to be defined.

Descriptive sensory evaluation of gari produced from fermentation of cassava using some selected Rhizopus species

Two local varieties of cassava (Manihot esculenta crantz) pulps named “okoiyawo” and “odongbo” were fermented with pure Rhizopus oligosporus, R. nigricans and R. oryzae. The products were subsequently processed in to “gari” (a roasted fermented cassava meal), the form in which it is popularly consumed in Nigeria. The selected process variables are cassava varieties, starter culture and fermentation time (2, 4 and 6 days). Fifteen randomly selected and trained panelists in the University carried out descriptive sensory analysis which characterized color, taste, flavor, smoothness, moldability and consistency of “gari” and “eba”. The sensory evaluation of the samples showed that the creamy-white is the most dominant color. A peculiar flavor, fine, and sour “gari”, consistent and moldable “eba” was also obtained. The optimum fermentation time for sensory quality is 48 h (2 days). The samples produced from “odongbo” are of good quality than the ones produced from “okoiyawo”. The selected Rhizopus species had a significant effect on the taste, flavor, and moldability of “eba”. There were significant differences (p<0.05) in the consistencies of the “eba” samples. The highly consistent ones are “odongbo” products while the ones made from “okoiyawo” are mildly consistent. There were no significant differences (p<0.05) in the moldability of “eba” samples. Key words: Gari, Sensory evaluation, Rhizopus species.

Characterization of products from sawdust biodegradation using selected microbial culture isolated from it

Characterization of products from sawdust degradation using selected microbial culture isolated from it was carried out. A composite sawdust waste sample was collected from MCC timber market in Calabar. The sample was diluted using serial dilution method and inoculated on Nutrient agar and Sabauraud dextrose agar using pour plate technique and incubated at 370C and 270C respectively. Five bacteria species and 3 species of fungi were identified which included Bacillus sp, Serracia mercescens, Micrococcus sp, Pseudomonas aeruginosa, Streptococcus sp, Aspergillus niger, Rhizopus sp and Penicillumsp. The bacteria and fungi species were individually and in combination inoculated into sterile sawdust containing sterile water. These were kept at 270C for 21 days. Protein, glucose contents and chemical components in the degraded sawdust samples were determined using GC-MS chromatography. It was observed that Aspergillus niger degradation had protein content 7.87g/l, Serracia mercescens and Aspergillus niger 6.56g/l, and Serracia mercescens 5.75g/l. These organisms used lignocellulolytic enzymes and similar enzymes in the degradation process. In the case of glucose, the combined degradation produced 2.24g/l, Aspergillus niger 2.05g/l and Serracia mercescens 1.94g/l. It was also observed that sawdust inoculated with Serratia marcescens produced 14 compounds while the combined species of Aspergillus niger and Serratia marcescens produced only 12 compounds. The following compounds Methylene cyclo propane carboxylic acid, Glycine N-Cyclopropylcarbonyl-methyl ester, acetic acid, propanoic acid, benzaldehyde, thiophene, tetrahydro, furfural and propanoic acid 2,2-Dimethyl-2-ethylhexyl ester were detected from the combination of Serratia marcescens and Aspergillus niger though in different concentrations. The percent concentrations of the compounds from Serratia marcescens range from n-Hexadecanoic acid 3.59 to Methylene cyclo propane carboxylic acid with 11.56 while Serratia marcescens and Aspergillus niger range from Butanoic acid, 4-chloro 3.59 to Benzaldehyde with 11.56. Microbial degradation of sawdust produced economically important products and therefore can contribute to the economy of this country at the same time reduce pollution caused by it which is a novel. Key words: Sawdust, biodegradation, bioactive, extracts, microbial culture, lignocellulosic.

Fluorescent staining for the rapid diagnosis of rare invasive fungal infections

Objective To evaluate the performance of an enhanced fluorescent staining for the rapid diagnosis of invasive mycosis, especially rare cases, considering the traditional culture method always leads to delays in clinical diagnosis for its time consuming. Methods Cases of invasive mycosis identified by fluorescent staining in our hospital from September, 2017 to September, 2018 were retrospectively analyzed. Three rare invasive infections were reported in this study. Clinical specimens were pretreated using standard procedures and then smeared on slides along with the enhanced fluorescent dye. Species of the pathogens were identified according to their morphology under fluorescent microscope. The traditional culture method was used as a standard method to identify the pathogenic species based on their colony morphology, followed by PCR and sequencing analysis for further confirmation. Results Three cases of invasive mycosis caused by rare pathogens of Talaromyces marneffei, Mucorales and Prototheca were rapidly diagnosed with the fluorescent staining method. Sequencing results indicated the species were Talaromyces marneffei, Rhizopus arrhizus and Prototheca wickerhamii. Conclusions Fluorescent staining is a rapid, economic and direct method for the diagnosis of invasive mycosis. The morphology of fungi is clear and easy to identify after fluorescence staining, which could be used for indicative diagnosis of highly suspected invasive mycosis and serve as an important complement to the traditional culture method, especially for the diagnosis of rare or uncultured fungal pathogens. Key words: Fluorescent staining; Rare fungus; Rapid diagnosis

Mycoflora and Public Health Risks of Smoked Fish Sold in Port Harcourt Markets, Nigeria

Fish is a preferred source of protein globally, especially in developing countries like Nigeria. It is a savoured protein source in the Niger Delta, including Port Harcourt. Smoking is used to preserve fish by reducing its moisture content with a view to improved shelf life. This study aimed at determining the Mycoflora and the Public Health risks of smoked fish sold in Port Harcourt Markets. A total of 54 fish samples were collected from three strategic markets; Mile one, Oil Mill and Creek Road markets. Fish collected consists of 6 different species; Gadus morhua, Pseudotolithus typhus, Lutijanus goreensis, Ethalmosa fimbriata, Pseudotolithus senegalensis and Dasyatis pastinaca. All samples were grouped accordingly. Mycological study of fish samples was done using standard methods on Sabouraud Dextrose Agar. There was a significant difference in the mycoflora counts of smoked fish from different markets (p<0.05). Fungal load ranged from 1.23±0.08 x103 sfu/g in Lutjanus goreensis to 8.89±0.10 x 103 sfu/g in Gadus morhua, at Creek road market. From Mile 1 market, Lutjanus goreensis still hosted the highest population of 13.25±0.7 x 103 sfu/g and Dasyatis pastinaca had the least; 0.66±0.01 x 103 sfu/g. At Oil mill market, Ethalmosa fimbriata hosted 13.23±0.47 x 103 sfu/g while Gadus morhua had 0.77±0.02 x 103sfu/g. The fungal load in all fish from all three markets were significantly high for food and calls for attention. Nine fungal genera; Saccharomyces spp, Rhizopus spp, Penicillium spp, Mucor spp, Fusarium spp, Cladosporium spp, Candida spp, Absidia spp and Aspergillus spp, were isolated. All six fish species studied recorded more than 50 % occurrence of fungal species in all the markets. The mycoflora of smoked fish sold in Port Harcourt markets suggest significant public health risks. The need for improved storage and handling of this important protein source is high towards reduced public health risk. Proper preparation method, such as boiling, is strongly advocated.

Leaf rot caused by Rhizopus oryzae on pak choy (Brassica campestris ssp. chinensis) in China.

Pak choy ( Brassica campestris ssp. chinensis L.) is the major vegetable crop cultivated in China. During December 2017, leaf rot was frequently observed on leaves of pak choy in greenhouses of Shanghai, China. Diseased leaf samples were plated onto acidified potato dextrose agar and fungal cultures were isolated and identified as Rhizopus oryzae , based on morphological features and molecular identification. Definitive identification as R. oryzae was based on the comparative molecular analysis of rRNA gene sequences. Blast analysis revealed 99% similarity with R. oryzae . Pathogenicity was determined by inoculating healthy pak choy leaves and plants with hyphal suspensions of R . oryzae. The fungus was re-isolated from developing similar lesions on the inoculated plants and identified as similar to the inoculated fungus, thus fulfilling Koch’s postulates. This is the first report of fungal leaf rot caused by R. oryzae on pak choy in China.

Screening for antifungal activity of garlic (Allium sativum) powder against mycelia growth of three post-harvest pathogens

Screening for antifungal activity of garlic powder against mycelia growth of three post-harvest pathogens (Aspergillus, Rhizopus and Mucor species) was investigated in this study. Five grams of malt extract agar (MEA) were poured into a conical flask, 100 ml of water and different weight of garlic powder (1, 3, 5 and 7 g) were separately added, stirred and later sterilized while MEA medium with no garlic added (0 g) served as control. The mycelia of each post-harvest pathogen was cut with 6mm cork borer and placed on the solidified medium in the Petri dish and incubated at 28±2oC for 72 hours. Phytochemical screening of the garlic powder was also investigated. Results from this study showed that the different weights of the garlic powder apart from the control (0 g garlic) significantly inhibited the mycelia growth of the three post-harvest pathogens tested in the study and the order of antifungal activity of the garlic powder against mycelia growth of Aspergillus, Rhizopus and Mucor species was 7 g > 5 g > 3 g > 1 g > 0 g, 5 g > 7 g >1 g > 3 g > 0 g and 7 g > 5 g > 3 g > 1 g > 0 g respectively. The antifungal activity of the garlic powder may be related to the presence of active antimicrobial agents including alkaloids, saponins, tannins, flavonoids and cardiac glycosides that were detected in the powder. DOI: http://dx.doi.org/10.5281/zenodo.2635824

Aflatoxigenic fungi in Nigerian poultry feeds: Effects on broiler performance

Aflatoxigenic fungi common to poultry feeds from Nigerian feed mills were investigated and their effects on broiler production were determined. Sixty two weeks old Abor-acre broilers were randomly divided into 5 treatment groups. Each treatment group had 3 replicates of 4 birds each. Birds in each treatment group were fed feed from one of five companies. Feed intake and body weights were determined. Blood samples were analyzed for hematological parameters. Feeds were analyzed for aflatoxin concentration using reverse phase High Performance Liquid Chromatography (HPLC). Aflatoxigenic fungi were identified by sequencing of the fungal ITS region. The major fungal contaminants identified in most of the feed samples were Aspergillus and Rhizopus species. Total aflatoxin content (AFB1+AFB2+AFG1 +AFG2) of the feeds ranged from <0.8 to 370±120 µg/kg. Feeds from three companies had aflatoxin concentrations above the European Community Regulatory Limits (ECRL, 20 μg/kg). Aflatoxin level was positively related to packed cell volume (PCV) and hemoglogin (Hb), although the relationship was not statistically significant. PCV and Hb were positively related. A negatively significant relationship was observed between the aflatoxin levels and WBC of the birds, feed intake and reduced body weight possibly because of the high aflatoxin concentrations in the feeds. The study has highlighted the effects of long storage time and poor processing of feed on intake and broiler performance. Key words: Aflatoxin, broilers, feed, hematology, fungi.

Regulation of Ester Synthesis Activity of Rhizopus chinensis Lipase

Regulation of Ester Synthesis Activity of Rhizopus chinensis Lipase

Study on the Intracellular Glycosyl Donor and Structural Function of Cellobiose Synthase from Rhizopus stolonifer

Study on the Intracellular Glycosyl Donor and Structural Function of Cellobiose Synthase from Rhizopus stolonifer

Preliminary studies on the laxative properties of Senna alata L. and Hollandia yoghurttm

Experiments on Senna alata aqueous extract and Hollandia yoghurt were done to determine active compounds responsible for their laxative properties and to further establish sample vulnerability to microbial attack. Phytochemical screening was performed on test substrates to analyze for alkaloids, flavonoids, tannins, saponins, terpenoids and steroids. Escherichia coli (Gram negative), Micrococcus species (Gram positive), Klebsiella pneumoniae (Gram negative), Enterocococcus species (Gram negative) and Salmonella species (Gram negative) were test bacteria while Penicillium species, Trichophyton species, Rhizopus species, Fusarium oxysporium and Aspergillus niger were test fungi used for microbial assays. The results show that alkaloids, tannins, saponins, terpenoids and steroids were found in S. alata while only alkaloids, terpenoid and steroid were found in Hollandia yoghurt. S. alata had activity against Penicillium spp., Trichophyton spp. and Rhizopus spp., while Hollandia yoghurt showed no antifungal activity. Aqueous extract of S. alata and Hollandia yoghurt are however together active against test bacteria of which, K. pneumonia is common. Key words: Laxative, Senna alata, hollandia yoghurt.

FIRST REPORT OF RHIZOPUS SOFT ROT OF SWEET POTATO (IPOMOEA BATATAS) CAUSED BY RHIZOPUS MICROSPORUS IN KOREA

Rhizopus soft rot caused by Rhizopus spp. is one of the most important post-harvest diseases of sweet potato storage roots all over the world (Harter et al., 1921). In 2016, a soft rot diseased sweet potato was collected from a farmer’s field in Haenam region, Jeonnam province, Korea. Blackish sporangia along with fungal mycelia were observed at the surface of sweet potato roots. The fungus was isolated on PDA forming a white, dense colony with globose or subglobose sporangia that turned blackish upon sporulation. Sporangial size varied and the sporangiospores were uniform, oval with pointed ends and (3.8–6.5 × 3.3–5.8) µm (n = 20) in size. To confirm the identity, total genomic DNA was extracted and the ITS region of rDNA was amplified using the ITS5/ITS4 primer pair. The purified product was sequenced and the sequence deposited in the GenBank (accession No. KY606252). Maximum parsimony phylogenetic analysis clustered our isolate SPL16012 with the type strain of R. microsporus (CBS 699.68). Molecular and morphological observations described above suggested the microorganism was Rhizopus microsporus (Walther et al., 2013). Koch’s postulates were completed by inoculating two local sweet potato varieties with 5 mm agar plugs and three replications. A disease symptom similar to the original rot was seen on the inoculated sweet potatoes and the pathogen was reisolated. No symptoms were seen on the non-inoculated agar plug control. To the best of our knowledge, this is the first report of R. microsporus on sweet potato in Korea.

Microbial Estimation and Characterization of Wastewater and Sludge in Awka Metropolis, Nigeria

This study focuses on the estimation and characterization of microorganisms isolated from wastewater and sludge in Awka metropolis, Nigeria. The samples were collected randomly from four (A, B, C and D) respective areas, analyzed microbiologically by homogenizing the samples under aseptic conditions to obtain a homogenous mixture, the isolation techniques used was pour plate methods as described by Cheesbrough, (2010); Joanne et al, (2011); APHA, (1989). The samples were diluted serially, inoculated on to MacConkey agar and Sabouraud Dextrose agar media each and microorganisms were isolated; wastewater had a range from 44 to 100 colonies and total of 284 (71 ± 24.30), CFU / ml (10-4) of 1.0 × 107 to 8.0 × 106 with total count of 19.4 (4.85 ± 2.96) × 106, while sludge was ranges from 60 to 120 colonies with a total of 358 (89.5 ± 29), CFU / ml (10-4) ranged from 1.0 × 107 to 7.0 × 106 with total count of 15.2 (3.8 ± 3.1) × 106. The colony and the morphology of the isolates were recorded, the bacterial isolates were characterized by motility tests, Gram staining and identified by biochemical tests. The fungal isolates were microscopically examined using a wet mount procedure. From the results obtained 8 bacterial and 7 fungal isolates were identified from both the wastewater and the sludge; Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Micrococcus leteus, Enterococcus faecalis, Serratia mercescens and Yersinia enterocolitica. Acrophialophora fusispora, Epicoccum Purpurascens, Rhizopus microsporus, Exophiala spinifera, Cladosporium cladosporiodes, Aspergillus niger and Phaeoacremonium parasiticum. Results also showed that staphylococcus aureus have the highest percentage of occurrence in wastewater, while in sludge Micrococcus species have the highest percentage of occurrence.

Shuanghuang burn ointment in vitro antibacterial activity of common fungi infectious

Objective To evaluate the antibacterial activity of fungal infection about Shuanghuang burn ointment in vitro. Methods The clinical isolates of candida albicans, candida tropicalis, candida albicans, candida albicans, aspergillus fumigatus, aspergillus niger, aspergillus flavus and rhizopus were produced with agar plates containing bacteria.Application of modified agar diffusion method with Shuanghuang burn ointment and clotrimazole and ketoconazole were cultured.The growth status of the strain was observed and the diameter of bacteriostatic circle was determined. Results Shuanghuang burn ointment form obvious bacteriostatic ring in the culture medium of Rhizopus.Compared with clotrimazole and ketoconazole, there was significant difference(P<0.05). In the experiments of aspergillus and candida culturesm, Shuanghuang burn ointment could not form obvious bacteriostatic ring. Conclusion Shuanghuang burn ointment has certain inhibitory effect on rhizopus in vitro.There is no obvious effect on candida and aspergillus. Key words: Fungi; Burns; Traditional Chinese medicine; Shuanghuang burn ointment

Biosorption of heavy metals onto different eco-friendly substrates

Fungi play an important role in biosorption of heavy metals in heavily contaminated soil. Five metals-tolerant fungal species were isolated from two different contaminated soil (soils 1 and 2). The number of fungal colonies isolated from the contaminated soil 2 was higher than that of soil 1. The most resistant fungal species for the toxic studied metals (Pb, Cd, Cu and Zn) was Rhizopus stolonifier followed by Macrophomina phaseolina. It was established that the metal toxicity was related to the contamination levels, the physicochemical properties including pH, conductivity, organic matter and carbonate contents of the soils. This study confirmed the good ability of different chemicals (CaCO3, MO, Zeolite and phosphate) and biological fungal substrates (M. phaseolina and R. stolonifier) in bioremediation of polluted soils and reducing different heavy metals levels as compared to the control, especially for fungi. M. phaseolina amendment was superior in reducing the chemically available heavy metals in the studied soils. Key words: Heavy metals, fungal adsorption, soil remediation, amendments, sequential extraction technique.

Isolation of Coprophilous Mycoflora from Different Dung Types in Some Local Government Areas of Niger State, Nigeria

This study investigated coprophilous mycoflora on different dung types in some Area of Niger State. Dung samples of four herbivorous animals (Camel, Cow, Donkey and Horse) were collected from three areas (Enagi, Lapai and New Bussa) in Niger State, Nigeria. The dungs were dried in the Department of Biological Sciences Laboratory, Ibrahim Badamasi Babangida University Lapai. A total of six (6) species of macro fungi (Agaricus campestris, Panaeolus papilionaceus, Agaricus bisphorus, Protostropharia semiglobata, Deconica coprophila, Copelandia cyanescens) and six (6) species of micro fungi (Aspergilous. niger, A flavus, A. fumigates, Alternaria sp, Pencillium sp, and Rhizopus stolonifer) were isolated. A. campestris has the highest percentage (40%) of macro fungi (from cow dung), while the least was A. bisphorus with (0.02%). Alternaria sp has the highest (33.26%) among the micro fungi isolated. From horse dung, A. fumigates was isolated with the least percentage of occurrence of 0.10% among the micro fungi. On this note, the animal dung investigated consists of both edible and poisonous fungi. Public enlightenment is therefore recommended on the good and bad effects these fungi. They may also be harnessed for industrial use.

Rhizopus arrihizus swollen spores induce mice dendritic cells to Th1 and Th17 differentiation

Objective To study the mechanism of adaptive immunity against Rhizopus arrihizus (R.arrihizus) infections. Methods Bone marrow derived dendritic cells (BMDCs) were separated from C57BL/6 mice and Card9-/- mice and then were cultured in vitro. Resting spores and swollen spores of R. arrihizus were in vitro co-cultured with BMDCs with or without Syk inhibition. Secretion of cytokines (IL-23, IL-1β and IL-12) was analyzed by ELISA after 24 hours of culture. Naive T cells derived from C57BL/6 mice were in vitro co-cultured with spore-stimulated BMDCs for four days. Levels of IL-17A and IFN-γ in supernatants of cell culture were analyzed by ELISA. Flow cytometry was performed to analyze T cell differentiation. Confocal microscopy was used to observe the images of stained β-glucan on the surface of resting and swollen spores. Swollen spores were co-cultured with Dectin-1, Dectin-2, TLR2 and mannose receptor (MMR), and the binding results were analyzed by flow cytometry. Results Swollen spores but resting spores could induce the maturation of BMDCs and promote the secretion of cytokines (IL-23, IL-1β and IL-12). Co-culturing T cells with swollen spore-stimulated BMDCs enhanced their differentiation to Th17 and Th1. In addition, swollen spores promoted the secretion of Th1-related cytokine (IFN-γ) and Th17-related cytokine (IL-17A). Adding Syk inhibitor to Card9-/- BMDCs or wild type BMDCs significantly inhibited the secretion of cytokines and T cell differentiation, especially in the Card9-/- group. β-glucan was overserved on the surface of swollen spores, but not on resting spores. On the surface of swollen spores existed pathogen associated molecular patterns (PAMPs) that could bind with Dectin-1 and TLR2. Conclusion Swollen spores of R. arrihizus could active BMDCs to secrete cytokines of IL-23, IL-1β and IL-12 and trigger T cell responses in vitro. The possible mechanism might be associated with β-glucan exposed on the surface of swollen spores that binds with Dectin-1. The responses between BMDCs and R. arrihizus are Syk-Card9-dependent. Key words: BMDCs; Rhizopus arrihizus; Syk-Card9

FUSARIUM PROLIFERATUM, THE MAIN CAUSE OF CLOVE ROT DURING STORAGE, REDUCES CLOVE GERMINATION AND CAUSES WILT OF ESTABLISHED GARLIC PLANTS

Eight fungal species belonging to six genera, i.e. Aspergillus niger , Aspergillus ochraceus , Botrytis alli , Fusarium oxysporum , Fusarium proliferatum , Penicillium purpurogenum , Rhizopus stolonifer and Stemphylium botryosum , were isolated from decayed garlic cloves. F. proliferatum had the highest frequency of occurrence and was found to be highly pathogenic to garlic cloves. The other fungal species were less frequent and aggressive. Garlic bulbs (cvs Balady and Sides 40) were stored at room temperature and at 5°C for six months after harvest. It was observed that clove rot and its severity increased with time in both cultivars and storage conditions. Rot incidence and severity were highest in cv. Balady at room temperature. In pot experiments, inoculation of garlic cloves with F. proliferatum before planting affected the percentage of plant emergence and severe wilt symptoms developed gradually on the surviving plants. Isolation from selected seedlings showing wilt symptoms yielded the same F. proliferatum that had been used for inoculation. The optimum temperature for F. proliferatum growth was 25°C, maintained for nine days. In in vitro assays Carbendazim had a strong inhibition effect of fungal growth followed by Metalaxyl 8%+Mancozeb 64% and thiophanate-methyl. The bioagents Trichoderma harzianum , T. viride , T. koningii , T. virens and T. album inhibited F. proliferatum growth.

Anti-oxidative and Anti-inflammatory Activities of Fermented Turmeric (Curcuma longa L.) by Rhizopus oryzae

Anti-oxidative and Anti-inflammatory Activities of Fermented Turmeric (Curcuma longa L.) by Rhizopus oryzae

بررسی توانایی چند گیاه دارویی در کنترل قارچ های عامل پوسیدگی انباری Rhizopus nigricans) و Alternaria alternate) در گوجه فرنگی های تولید شده در سامانه های کشاورزی رایج و زیستی

بیماری پوسیدگی ریزوپوسی و نقطه سیاه از مهم ترین بیماری های انباری در گوجه فرنگی می باشند. به منظور بررسی توانایی چند گیاه دارویی بر ماندگاری و کنترل قارچ های عامل پوسیدگی انباری Rhizopus nigricans) و Alternaria alternate) در گوجه فرنگی های تولید شده در سامانه های کشاورزی رایج و زیستی، آزمایشی به صورت فاکتوریل در قالب طرح کاملا تصادفی با 14 تیمار و سه تکرار در دانشگاه فردوسی مشهد در سال 1389 اجرا شد. دو سامانه تولید شامل گوجه فرنگی رایج و زیستی (ارگانیک) و شش گونه گیاهی (آویشن (Thymus vulgaris L.)، پونه (Mentha pulegium L.)، نعناع فلفلی (Mentha piperita L.)، اکالیپتوس (Eucalyptus globules L.)، کرچک (Ricinus communis L.) و گوجه فرنگی (Lycopersicom esculentum Mill.)) به همراه تیمار شاهد به ترتیب عامل اول و دوم در این آزمایش بودند. بر اساس نتایج آزمون غیر پارامتری کروسکال– والیس، تفاوت معنی داری بین سامانه های تولید گوجه فرنگی های ارگانیک با نوع غیرارگانیک آن از نظر سرعت پوسیدگی انباری ناشی از رشد قارچ های بیماری زا مشاهده شد. به طوری که در گوجه فرنگی های ارگانیک، سرعت پوسیدگی (47/1 عدد میوه در هفته) تا حدود 20 درصد کمتر از نوع غیرارگانیک آن بود. نتایج حاصل از آنالیز غیرپارامتری گونه های گیاهی نیز حاکی از وجود تفاوت بین این گونه ها از نظر تأثیر بر سرعت پوسیدگی انباری در گوجه فرنگی بود؛ به طوری که به جز کرچک و گوجه فرنگی، سایر گیاهان دارویی منجر به کاهش معنی دار سرعت رشد و توسعه قارچ های بیماری زا در انبار شدند.