Blotter Method Research Articles

Prevalence of Seed Borne Fungi Associated with Chickpea Seeds and Biological and Chemical Control of Fusarium oxysporum Causing Wilt Disease

A total of 20 chickpea seed samples were collected from BARI, Gazipurand different locations of Savar, Dhaka district. Blotter method was used for detection of the associated fungi of chickpea seeds. Altogether 14 fungi comprising 12 genera namely Aspergillus flavus, Aspergillus niger, Aspergillus sp, Botryodiplodia theobromae, Botryti cinerea, Curvularia lunata, Chaetomium globosum, Cladosporium sp., Colletotrichum dematium, Fusarium oxysporum, Macrophomina phasaelina, Rhizoctonia solani, Rhizopus stolonifer and Stemphylium sarciniforme were isolated from chickpea seed samples. Among the fungi isolated fungi, F. oxysporumwas most prevalent with an average incidence of 18.95% and found in all the seed samples. The germination of seed samples varied from 55-90 % on blotter. The pathogenic fungi and other storage fungi like Aspergillus caused lower the germination of the seeds.A pathogenicity test was conducted with 20 isolates of F. oxysporum against their origin of chickpea seed samples in pot culture. The pathogenecity ranged from weak to highly pathogenic. The isolates FO 19, FO 17, FO 11 and FO 18 were highly virulent. The isolates FO 9, FO10 and FO 15 were virulent and rest of the isolates were moderately virulent. The isolates FO 2 and FO 3 were weak pathogen.J. Environ. Sci. & Natural Resources, 10(2): 45-54 2017

In-vitro study on prevalence of mycoflora in wheat seeds

A study on incidence of mycoflora was carried out by blotter method in wheat seeds. Forty seed sample of wheat (Triticum aestivum) was collected, ten varieties/genotypes each from Chitwan; Kaski; Banke and Lalitpur. The study was done at Seed Quality Control Center, Hariharbhawan, Lalitpur, Nepal, during August to December, 2013, with the objective of determining fungi associated with wheat seeds in-vitro. A total of eighteen species of fungi within thirteen genera were detected. Alternaria alternata and Bipolaris sorokiniana were predominant in all the varieties/genotypes and locations. Percentage frequency and type of fungi detected varied with variety and location. Among all fungi, mean frequency (76.00%) and relative abundance (55.15%) were highest of Alternaria alternata. Among the seeds of different location, B. sorokiniana was found highest from the seed of Banke and A. alternata from seeds of Lalitpur. Lowest percentage frequency of fungi was found in genotype BL 4009 (3.06%) from Chitwan and in variety Nepal 297 (6.25%) from Kaski, and highest in genotype BL 1177 (16.40%) from Banke. Nepalese wheat seeds appeared prevailed with many pathogenic fungi. Therefore, selection of wheat seeds from resistant varieties and areas with lower temperature and relative humidity, and their treatment is suggested to reduce disease and increase yield.Journal of the Institute of Agriculture and Animal Science. Vol. 33-34, 2015, Page: 27-34

Detection and chemical control of Cercospora sojina infecting soybean seed in Argentina

Frogeye leaf spot (FLS) of soybean caused by Cercospora sojina Hara is an important disease in the Argentine Pampas region. The primary inoculum sources of the disease are infected seeds and plant debris. Thus, use of pathogen-free or fungicide-treated seeds is crucial to prevent the introduction and further spread of the disease. The aims of this research were i) to quantify C. sojina incidence in harvested soybean seeds, ii) to compare media-based incubation methods for detection of the pathogen in seeds, and iii) to evaluate the effect of fungicide seed treatments in reducing FLS incidence. Among eight different detection methods evaluated, no difference in pathogen incidence was found, but the water restriction blotter method should be recommended as it is more time and cost-effective. Out of 13 different fungicide seed treatment combinations in three independent experiments, benzimidazole seed treatments resulted in zero FLS incidence. Any other of the tested fungicidal active ingredients either did not control the disease or did so poorly only when initial infection levels were low. Treating seeds with benzimidazole fungicides may help to reduce FLS incidence during initial soybean field stands when using infected seed lots.

Prevalence of Fungi With Seeds of Twenty Brri Released Rice Varieties and Seed Quality Analysis

A total of 20 rice varieties of BRRI dhan 56 to BRRI dhan 75 were collected from Bangladesh Rice Research Institute (BRRI) for seed quality analysis, detection and identification of fungi associated with seeds of selected rice varieties. Dry inspection indicated that the percentage of pure seeds ranged from 90 - 100. The highest percentage of pure seed was found in BRRI dhan 66 and BRRI dhan 70 (100) and lowest in BRRI dhan 68 (90). A total of 21 fungal species were isolated from the selected rice varieties following “Blotter and Tissue Planting” methods. They were Alternaria padwickii, A. tenuissima, Aspergillus flavus, A. fumigatus, A. niger, A. ochraceus, A. clavatus, A. terreus, Bipolaris sorokiniana, B. spicifera, Chaetomium globosum, Curvularia lunata, Drechslera oryzae, Fusarium sp.1, Fusarium sp. 2, Nigrospora sp., Penicillium sp., Pestalotiopsis guepinii, Rhizopus stolonifer, Syncephalastrum racemosum and Trichoderma viride. Among them Penicillium sp., Drechslera oryzae, Aspergillus ochraceus, A. flavus, A. fumigatus, A. niger and Fusarium sp.1 were predominant in most of the rice varieties. In Tissue Planting method Drechslera oryzae showed the highest mean per cent frequency (6.69) and lowest was in the Bipolaris sorokiniana (0.41). Maximum total fungal association was recorded in variety BRRI dhan 61 (156.79%) and minimum in BRRI dhan 66 (24.69%). In Blotter method Penicillium sp. showed the highest mean per cent frequency (7.56) and lowest was in Rhizopus stolonifer (1.71). Maximum total fungal association was recorded in BRRI dhan 63 (147.37%) and minimum in BRRI dhan 65 (19.21%). Germination percentage of seeds was highest in BRRI dhan 66 (88) followed by BRRI dhan 67 (82), BRRI dhan 74 (80) and lowest in BRRI dhan69 (24). The percentage of seedling mortality was highest in BRRI dhan 63 (42) and lowest in BRRI dhan 74 (8.0) followed by BRRI dhan 67 (10). Correlation coefficient and regression analysis indicated that prevalence of fungi has significant effect on seed germination and seedling mortality. The present research work suggests that out of 20 BRRI rice varieties, BRRI dhan 65, BRRI dhan 66, BRRI dhan 67 and BRRI dhan 74 showed better performances on the basis of percentage of pure seed, fungal association, seed germination and seedling mortality.
 Asiat. Soc. Bangladesh, Sci. 44(1): 79-89, June 2018

Development of Loop-Mediated Isothermal Amplification Assays for the Detection of Seedborne Fungal Pathogens Fusarium fujikuroi and Magnaporthe oryzae in Rice Seed.

Bakanae disease (caused by Fusarium fujikuroi) and rice blast (caused by Magnaporthe oryzae) are two of the most important seedborne pathogens of rice. The detection of both pathogens in rice seed is necessary to maintain high quality standards and avoid production losses. Currently, blotter tests are used followed by morphological identification of the developing pathogens to provide an incidence of infection in seed lots. Two loop-mediated isothermal amplification assays were developed with primers designed to target the elongation factor 1-α sequence of F. fujikuroi and the calmodulin sequence of M. oryzae. The specificity, sensitivity, selectivity, repeatability, and reproducibility for each assay was assessed in line with the international validation standard published by the European and Mediterranean Plant Protection Organization (PM7/98). The results showed a limit of detection of 100 to 999 fg of DNA of F. fujikuroi and 10 to 99 pg of M. oryzae DNA. When combined with a commercial DNA extraction kit, the assays were demonstrated to be effective for use in detection of the pathogens in commercial batches of infected rice seed of different cultivars, giving results equivalent to the blotter method, thus demonstrating the reliability of the method for the surveillance of F. fujikuroi and M. oryzae in seed-testing laboratories.

Incidence of seed mycoflora in different cultivars of safflower

An investigation was conducted to detect the associated seed mycoflora in safflower and its control. A total of 19 safflower seed samples were collected from major growing areas of safflower. Blotter method and agar plate methods were used for detection of seed mycoflora of safflower seeds. Across the two methods adopted, a total of seven fungal genera including Alternaria, Aspergillus, Chaetomium, Rhizopus, Curvularia and Fusarium were detected. The fungi detected were identified based on their cultural and morphological characteristics. The fungal species namely Alternaria carthami, Aspergillus niger were found associated with all the tested hybrids/varieties/germplasms while species of Chaetomium sp., Rhizopus sp., Curvularia sp. and Fusarium sp. were not detected in some of the hybrids/varieties/germplasms. Among the seven fungal species detected the occurrence of Alternaria carthami was high 47.94 per cent followed by Aspergillus niger . The cultivar, Nira showed higher per cent incidence of seed mycoflora. Per cent incidence of seed mycoflora varied across the methods adopted and cultivars tested the highest per cent incidence of 46% was observed with the fungus Alternaria carthami on Nari NH1 in blotter method. Out of the two methods tested blotter method was found superior over agar plate method in which higher number of fungi were recorded.

Effects of Some Plant Essential Oils against Fungi on Wheat Seeds

Abstract: Diseases, especially caused by seed borne fungi, are among the factors decreasing yield and quality of wheat. Common bunt is also an important seed borne disease of wheat worldwide. The objective of the study is to determine the effects of clove, ginger, mint, oregano and thyme oils on the fungal load of wheat seeds. In addition, effects of the oils on the germination rates of bunt spores were investigated. Blotter method was used to determine the effects of different concentrations (0.05 – 10%) of the oils on fungal load of wheat seeds. After incubation at 22°C for 7 days, seeds were investigated under stereomicroscope and fungi growing on the seeds were recorded. Germination rates of bunt spores were determined after incubation on water agar with different concentrations of oils. Highest doses of clove, mint and oregano oils totally inhibited the fungal growth on wheat seeds, but they also inhibited the germination of seeds. Lower doses failed to inhibit fungi on seeds, however they decreased or totally inhibited the germination of bunt spores. As a result, it was found that plant essential oils could be used against bunt disease of wheat as an alternative to fungicides. Key words: Triticum aestivum, seed-borne fungi, Tilletia spp., control, Blotter test, Germination rate.

Comparative efficacy of garlic, BAU-biofungicide, Bavistin and Tilt on seed borne fungal flora in chilli

Efficacy of BAU-Biofungicide (3%), garlic extract (1:1), Bavistin (0.2%) and Tilt 250EC (0.2%) were evaluated against seed borne fungal pathogens of chilli collected from Lakshmonkhola, Mugarchar and Tulatuli villages under Comilla district. Four hundred seeds of each sample were tested following blotter incubation and sand culture method. Using blotter incubation method, five different seed borne fungi, namely, Colletotrichum capsici, Alternaria tenuis, Aspergillus spp, Fusarium spp, and Curvularia lunata were detected from the chilli seeds. BAU-Biofungicide (3%) and followed by garlic extracts (1:1) was found most effective among five different treatments for increasing the germination percentage as well as controlling the associated seed borne fungi in chilli seed. Highest germination percentage (89.50%) was observed in BAU-Biofungicide (3%) treated seeds. Highest reduction of Colletotrichum capsici, Alternaria tenuis, Aspergillus spp, Fusarium spp, and Curvularia lunata was observed when seeds were treated with BAU-Biofungicide (3%) and garlic extract (1:1). The highest vigour index of chilli seed collected from Lakshmomkhola, Mugarchar and Tulatuli villages were 494.56, 403.23 and 333.37, respectively was observed in BAU-Biofungicide treated seeds.J. Bangladesh Agril. Univ. 15(1): 41-46, January 2017

Seed health and quality of some selected rice varieties and their management

A study was conducted for assessing seed health status of four varieties of rice (Oryza sativa) viz. BR 11, BRRI Dhan 28, BRRI Dhan 29 and BRRI Dhan 40 and management of seed borne fungal pathogens by selected chemical namely Thiovit (4%) and a bio-control agent BAU-Biofungicide @ 2% (Trichoderma based preparation) at Seed Pathology Center (SPC) and M.S. Laboratory, Department of Plant Pathology, Bangladesh Agricultural University (BAU), Mymensingh. Seed health test by blotter method revealed that seven seed borne fungi belonging to six genera viz. Alternaria padwickii (0.5%-1%), Bipolaris oryzae (1%-6.5%), Curvularia lunata (1%-5.5%), Fusarium moniliforme (3%-8.5%), Fusarium oxysporum (2%-9%), Aspergillus flavus (0.5%-1.5%) and Penicillium spp (0.5%-1%) were associated with the seeds. Germination of seeds of the four selected rice varieties varied from 94% to 98.50% (blotter method). In treated seeds, germination ranged from 88-100%. The highest germination (100%) was found in BRRI Dhan 28 when seeds were treated with BAU-Biofungicide and the lowest was (88%) in BRRI Dhan 29. The tested samples produced healthy seedlings (77 to 98%), diseased seedlings (2 to 15%), diseased seeds (0 to 7%) and dead seeds (0 to 5%). Upto 18.18% higher formation of healthy seedlings over control was achieved by treating seeds with BAU-Biofungicide and it also significantly decreased (upto 81.82%) formation of diseased seedlings over the control treatment. The highest vigor index (1306%) was in BRRI Dhan 28 when seeds were treated with BAU-Biofungicide and the lowest was (2805%) in BRRI Dhan 29 under control (untreated). Moreover, BAU-Biofungicide increased up to 81.82% Vigor index over untreated control. Asian Australas. J. Biosci. Biotechnol. 2017, 2 (1), 75-80

Xác định mầm bệnh trên hạt lúa giống Jasmine 85 tại An Giang

This study aims at identifying pathogens contaminating seeds of rice cultivar Jasmine 85 in An Giang to study disease control methods. A total of 36 seed samples was collected from nine main rice cultivation areas of An Giang, i.e., Châu Đốc, Thoại Sơn, Tịnh Biên, Tri Tôn, An Phú, Châu Thành, Châu Phú, Long Xuyên and Chợ Mới. Seven fungal pathogens were identified based on their morphological characterization using blotter method. They include Alternaria padwickii, Bipolaris oryzae, Sarocladium oryzae, Aspergillus sp., Fusarium moniliforme, Mucor sp. and Penicilium sp. Two bacterial pathogens Pseudomonas glumae and Xanthomonas oryzae pv. oryzae were furthermore identified from the samples. The bacterium Pseudomonas glumae was detected based on its colony mophorlogy on selective media whereas Koch’s postulates combined with PCR technique using specific primers were used to identify Xanthomonas oryzae pv. oryzae. These results serve as a basis for effective control of seed transmitted diseases in rice fields.

Studies on the mycoflora of maize grain

Maize is an important food and fodder crop. Its grains are important for the production of starch, oil and glucose. It is an important component of both human and animal diet. During storage grains undergo quantitative and qualitative losses. A large number of pathogenic fungi, bacteria, viruses and insects affecting maize cause combined world annual losses of 9.4% (Shrutelff, et al., 1980). Fungi affect quality of grain through increase in fatty acid, reduction in germination and finally spoilage of grain. The importance of fungi is also due to production of toxin that cause health hazards in human and animals. In the present study two variety of maize N 2277 and S 2727 which are locally grown crop in our area were collected directly from the field. Mycoflora of maize was tested by using blotter method. Moisture content, percent germination was also studied. A total of 8 fungi were observed from the grain.

Assessment of Seed Infestation Level of Brown Spot (Bipolaris Oryzae) in Different Rice Genotypes under Natural Epiphytotic Conditions

Bipolaris oryzae, the causal agent of brown spot disease, is an economically important pathogen of rice found in several rice growing countries in the world. Seed samples were collected from the rice experimental field comprised of different rice genotypes at National Rice Research Program, Hardinath, Dhanusha, Nepal in 2014 to determine the infestation level of B. oryzae and taxonomic identification of seed borne fungi by standard blotter method. The major recovered fungal mycoflora were B. oryzae, Pyricularia oryzae, Ustilaginoidea virens, Aspergillus flavus, Aspergillus niger, Curvularia oryzae, Rhizopus oryzae, Alternaria sp., Cercospora sp. and Penicillium sp. Seeds of all rice genotypes were infected with these fungi however frequency of fungal association varied among rice genotypes (from 12% to 96%). The percentage infection of B. oryzae was recorded maximum in all the rice genotypes compared to other seed-borne fungi. Madhaya dhan 845 and BI-0530-5-10-1-2 were the most infected genotypes and the infection percentage was 72% and 68%, respectively. Similarly, the least infected genotypes were Sabitri and TN-1 and infection level of 8% was recorded in both genotypes. Our findings may be used to predict disease occurrence and fungal transfer to new uninfected areas. Moreover, this study suggests that rice seed should be properly detected to check contamination by pathogens before sowing for effective and healthy crop production.Int J Appl Sci Biotechnol, Vol 4(3): 294-297

Investigation on quality and management of wheat seed in Bogra and Naogaon

The quality of wheat seed samples of 11 varieties viz. Akbar, Kanchan, Barkat, Sonalika , Paban, Prodip, Satapdi, BARI gom 25, BARI gom 26, BARI gom 27 and BARI gom 28 from 7 different Upazillas of Bogra and 5 different Upazillas of Naogaon were tested and categorized into six components viz. Grade-0 (72 to 86.7%), Grade-1 (2.9 to 7.5%), Grade-2 (2.1 to 6.0%), Grade-3 (1.7 to 4.5%), Grade-4 (2.4 to 8.4%) and Grade-5 (1.5 to 7.6%). The highest percentage of Grade-0 seeds (86.7%) was recorded in wheat variety of BARI gom 28 and the lowest percentage of Grade-0 seeds (72%) was recorded in variety Kanchan. The moisture content of the seed samples ranged from 10.22 to 13.81%, where the highest percentage of moisture content was found in wheat variety of Kanchan and the lowest in wheat variety of BARI gom 28. The 1000-seed weight ranged from 40.00 to 42.85 g where significantly highest weight was recorded in wheat variety of Sonalika followed by BARI gom 27 and the lowest in BARI gom 28. Health test by Blotter method resulted eight different seed borne fungi belonging to six genera viz. Bipolaris sorokiniana (0.5 to 30.5%), Alternaria tenuis (0.5 to 25%), Fusarium moniliforme (0.0 to 33.5%), Fusarium oxysporum (2.7 to 53%), Curvularia lunata (0.0 to 5.5%), Aspergillus niger (0.0 to 18.5%) and Penicillium spp. (0.0 to 1.5%). Out of 11 samples tested germination of seeds ranged from 98.0 to 73.5%. Wheat seeds of variety Kanchan was treated with plant extracts, BAU-Biofungicide and chemical fungicides (Bavistin, Tilt and Provex) while the highest (11%) incidence of Bipolaris sorokiniana was recorded in untreated control and the lowest (0.0%) in seed treatment with BAU-Biofungicide followed by seed treatment with Provax and Tilt. Seed germination ranged from 56.0 to 98.0% where the highest (98.0%) and lowest (56.0%) germination was recorded in case of seed treatment with BAU-Biofungicide and Tilt. BAU-Biofungicide increased 41.75% vigor index over untreated control.Progressive Agriculture 27 (2): 101-109, 2016

DETECT THE FUNGI THAT ASSOCIATED WITH ZINNIA SEEDS AND IT, S EFFECT TO PLANT GROWTH STAGE

This study was carried out to detect the Dematiceous hyphomycetes fungi that associated with Zinnia seeds and to test their pathogenicity and effect on seed germination and foliage. Results of isolation and identification showed the existence of 8 species of these fungi associated with Zinnia seeds. Alternaria alternata was presented in 81.8% of seed samples with highly rate of frequency 77% in sample No.1. The preliminary test of the pathogenicity by cabbage seeds which included three separated experiments, showed that the 34 tested isolates caused a significant reduction in the rate of cabbage seeds germination except B18 isolate (Phoma eupyrena). Isolates B39 and H7 (Alternaria alternata ) were highly Pathogenic which the percentage of germination in their treatments were 0% compared to 98% in the control. Also test the results of effect of pathogenic isolates on Zinnia seeds germination by using blotter method which included two experiments, Showed that all isolates caused a significant reduction in Zinnia seeds germination in comparing with control treatments except H6 isolate. two isolates B39 and H7(A. alternate ) gave a highly significant reduction which the percentage of germination in their treatments was 18% and 20% respectively compared with control treatment. Under green house conditions, isolated H7 and B39 (A. alternate) , A13 (D. state of cochliobolus spicifer) and B8 (P. exigua ) were pathogenic for Zinnia plants with 100% disease incidence and 65-80% disease severity in comparing with control which the disease incidence and severity in their treatment was 2.5%. All these isolates significantly decreased the plant growth parameters.

Quality of some hybrid seeds of rice and control of seed borne fungi in Bangladesh

A study was conducted for assessing quality of 15 hybrid rice seed samples and management of seed borne fungal pathogens by three selected chemicals namely Bavistin (0.3%), Thiovit (0.3%) and Provax (0.3%) along with two botanicals such as: Garlic extract (Allium sativum) (1:1) and Allamanda leaf extract (Allamanda cathartica) (1:1) and a bio-control agent BAU-Biofungicide @ 3% (Trichoderma based preparation) at Seed Pathology Centre, MS Laboratory and Eco-friendly Plant Disease Management Laboratory of Department of Plant Pathology, Bangladesh Agricultural University, Mymensingh during 2013-14. Collected seed samples were categorized by dry inspection as apparently healthy seed (35.7 to 85.7%), discolored seed (0.5 to 22.2%), spotted seed (0.7 to 8.1%), broken seed (0.4 to 44.3%), deformed seed (0 to 1.4%), insect damaged seed (0 to 4.9%), chaffy seed (0 to 1.1%), varietal mixture (0 to 7.2%) and inert matter (0 to 2.6%). In case of purity analysis, pure seed ranged from 92.86 to 100.00%, other seeds 0 to 7.14% and inert matter 0 to 2.59%. 100% pure seed was recorded in Agomoni, Jagoron, Gold, Suborno, Hira-1, Hira-2, Hira-4 and Hira-6 collected from Ispahani Agro. Ltd., BRAC, Lal Teer seed Co. Ltd. and Supreme seed Co. Ltd. Seed treatment with Allamanda leaf extract, Provax and BAU-Biofungicide increased germination, Vigor index and decreased prevalence of seed borne fungi. Among the treatments, biofungicide increased germination 54.39% in blotter method and 89.58% in tray method over control. In addition, BAU-Biofungicide increased up to 713.78% vigor index over untreated control. BAU-Biofungicide may be recommended for controlling seed borne fungal pathogens of hybrid rice in Bangladesh.J. Bangladesh Agril. Univ. 13(2): 161-168, December 2015

Influence of fungi associated with watermelon seeds on physiological and health quality

Crop cultivation begins with direct sowing or seedlings production; it is important to use high quality seeds, highlighting physiological and health attributes. This study aimed to evaluate the physiological and health quality of watermelon seeds using different methodologies. We used four lots of untreated watermelon seeds of Crimson Sweet plant variety produced in the same year. Physiological performance was evaluated by a standard germination test, first count of germination, accelerated aging, electrical conductivity of seeds (Ec) and seedling emergence (S). Health quality was evaluated by a blotter method test where seeds were planted on well water-soaked blotters (filter papers), and incubated for seven days at 22oC under 12h alternating cycles of light and darkness; seedling symptom in paper roll test where seeds were planted such as a standard germination test, and incubated for seven days at 22oC under 12h alternating cycles of light and darkness; seedling symptom in autoclaved sand carried out with the seedlings’ emergence. First count of germination and electrical conductivity of seeds showed the lower quality of lots 1 and 2 in relation to the other lots, which were evaluated as similar in seedlings’ emergence. Identification of seedlings’ symptoms in paper roll and sand was not sensitive enough to quantify Aspergillus sp., Penicillium sp. and Rhizopus sp. presence in watermelon seeds. Electrical conductivity and first count of germination tests allow the evaluation of physiological performance of watermelon seeds properly, based on the correlation value (+/- 1). The blotter test is the most efficient test to evaluate health quality of watermelon seeds. Aspergillus sp. incidence is correlated with low physiological performance of watermelon seeds.

Effect of seed treatment on seed borne fungi of rice

Farmers of our country are not aware about seed treatment for controlling seed borne fungi. Seeds of 3 rice varieties viz. BR11, BRRI dhan30 and BRRI dhan33 were collected from farmers houses of Gopalpur, Tangail. Three seed treating fungicides viz. vitavax 200 vitavax 200 (0.25%), thiovit (0.25%) and cupravit (0.25%) were used. Collected seed samples were tested by dry inspection and blotter method. The highest and the lowest germination were recorded in seed samples of BRRI dhan30 (90%) and BRRI dhan33 (75%). After seed treatment the highest and the lowest germination were recorded in seed samples of BRRIdhan30, BRRI dhan33 (100) treated by vitavax 200 (0.25%) and BR11 (80%) in control. Seed health test by blotter method revealed seed borne fungi belonging to six genera viz. Bipolarisoryzae (2.5 to 8.53%), Alternariapadwickii (5.3 to 13.35%), Fusariummoniliforme (11.66 to 21.67%), Fusariumoxysporum (1.25 to 4.35%), Curvularialunata (1.95 to 7.5%) and Aspergillusspp (1.75 to 6.54%) were encountered. Bur after seed treatment remarkable improvement viz. Bipolarisoryzae (0.15 to 3.75%), Alternariapadwickii (0.0 to 3.0%), Fusariummoniliforme (2.16 to 5.83%), Fusariumoxysporum (0.0 to 3.0%), Curvulariaunata (0.0 to 2.56%) and Aspergillusspp (0.0 to 1.5%) were encountered. Vitavax 200 was found most effective against the seed borne pathogens of rice. Nowadays, many botanical extracts such as neem, nishinda, garlic, alamonda and biological agent such as Trichoderma also using as seed treating agent and resulted significant higher germination and plant stand, less disease incidence and higher yield of different crops. So, the farmers should treat their seed before sowing in their field and through this technique they will be more benefited.Progressive Agriculture 27 (1): 48-56, 2016

Preservative potential of cumin essential oil for Pisum sativum L. during storage

AbstractThe samples of stored seeds of pea (Pisum sativum L.) were collected from 30 farmer markets. The mycobiota analysis showed presence of 15 fungal species and one species of insect Callosobruchus chinensis. The fungi such as Aspergillus flavus, A. niger, A. ochraceous, A. terreus were found to be dominant based on percent frequency of each in blotter method in unsterilized and sterilized seeds 18.9-7.9, 15.0-3.9, 12.2-3.7, 10.1-1.7, respectively, and in agar plate technique 17.9-8.3, 15.1-9.5, 12.8-5, 7.9.7-6.7, respectively. These species showed reduction in terms of weight loss, germination and protein content in pathogenicity testing. Essential oil extracted by hydrodistillation from fruits of Cuminum cyminum L. was evaluated against the most common occurring funi such as A. flavus and A. niger as well as the insect species C. chinensis and the oil exhibited high toxicity. The oil killed the tested fungi and showed thermostable nature at its minimum inhibitory concentration (MIC) of 400 ppm. The oil safely preserved pea seeds up to 120 days at 0.50 (1,000 ppm) and 0.76 ml (1,500 ppm) in polyethylene and jute bags of 500 ml capacity containing 400 g seeds separately. There were no changes in organoleptic appereance of food seeds during storage. The oil has beneficial effect on number of visible nodule formation and shoot and root dry biomass of 15-day-old plants in comparison to control sets. The cumin oil was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS).

Management of seed borne fungal pathogens of okra collected from seed companies

Effect of mehogoni, mehedi and allamanda extracts were tested to control seed borne fungi of okra seeds collected from 6 companies of notunbazar in Mymensingh district. Prevalence of seed borne fungi was studied by blotter method in the Seed Pathology Center (SPC) and MS Laboratory, Department of Plant Pathology, Bangladesh Agricultural University (BAU), Mymensingh. The highest germination percentage was recorded from ACI seeds (88%), while lowest (70%) in BADC seeds. Six predominant fungal genera were identified. These species were Fusarium oxysporum (5.08%), Aspergillus flavus (4.50%), Aspergillus niger (6.50%), Colletotrichum dematium (4.67%), Rhizopus stolonifer (3.33%) and Penicillium spp. (3.00%). Germination percentage and fungal association varied from company to company. The germination was ranged from 70-95% and infections were recorded 0.80-6.1% in all the treated seeds. Mehogoni extracts at the rate of 1:1 showed best performance in increasing seed germination (96.00%) next to allamanda (70%). Vigour index of okra seeds were increased 19.14% over untreated seeds by the treatment of mehogoni seed extracts at the rate of 1:1. Mehogoniseed extract at the rate of 1:1 seemed to be adoptable at the farmer?s level as an organic management practice.Asian J. Med. Biol. Res. December 2015, 1(3): 628-640

Study on Prevalence of Mycoflora in Wheat Seeds

Forty seed sample of wheat (Triticum aestivum) were collected from four locations viz. Chitwan, Kaski, Banke and Lalitpur and tested by blotter method at laboratory during 2013 for determining fungal pathogens associated with wheat seeds in Nepal. Eighteen species representing thirteen genera of fungi were recovered from the seed. Alternaria alternata and Bipolaris sorokiniana were predominant in all the varieties/genotypes from all the locations, where B. sorokiniana was strongly pathogenic in wheat crop. Percentage frequency and type of fungi detected varied with variety and locations. Bipolaris sorokiniana was highest (64.40%) in Banke than remaining three locations. Seeds of Chitwan had lowest percentage (5.50%) of seed infection as compared to other locations. Relative abundance of Alternaria alternata (55.10%) was highest as it was the most prevalent component of seed borne mycoflora, followed by Bipolaris sorokiniana (34.69%) and Cladosporium herbarum (7.19%). Differences in quantity of precipitation and relative humidity might be the possible reason for variation in frequency and type of fungi detected in wheat seeds of four locations.