Borne Fungi Research Articles

Comparative Studies on The Efficacy of Some Fungicides Activities on Fungal Seed Borne Pathogens of Commercial Maize Seeds

This study investigated the efficacy of some fungicides activities on fungal seed borne pathogens of two commercial maize seeds (Sammaz 15 and Sammaz 52). A total of 2500 seeds were randomly picked for each variety to represent a working sample from the seed reference collections. Out of the 2500 seeds, 400 seeds were surface–sterilized with 10% sodium hypochlorite solution, cultured and examined microscopically for the presence of fungal pathogens. Molecular analysis confirmed that all isolated pathogens matched with the reference accession from NCBI molecular database. Seeds were treated with different dosages of fungicides viz Thiram and Metalaxy + Tebuconazole and incubated for 5 days. The effect of the various fungicides on the incidence of seed- borne fungi, effect on seed germination and interaction of the fungicide were evaluated and analyzed. Percentage occurrence of the fungal pathogens revealed that Sammaz 15 have F. solani (29.0%), A. flavus (20.3%), A. niger (19.0%) and Rhizpus stolanifera (15.0%). In Sammaz 52, A.niger (40.0%), A. flavus (19.7%) and F. solani (27.0%). It was observed that F. solani was predominant in sammaz 15 while A. niger was predominant in Sammaz 52. Thiram (45.88 mm) at all doses showed greater inhibitory effects on mycelia growth than Metalaxyl + Tebucanozole (24.25 mm). The correlation analysis performed on the data set reveals that there is a negative significant correlation between zone of inhibition and percent disease incidence (r = -0.99***), but the relationship was positive with number of non-infected seeds (r = 0.99***). This shows that increasing the zone of inhibition will increase the number of non-infected seeds and the normal seedling (germination percentage). Thiram fungicides observed to be more effective in reducing the disease incidence than Metalaxyl fungicides.

UJI EFEKTIVITAS ANTIJAMUR EKSTRAK KULIT NENAS TERHADAP JAMUR TULAR BENIH DAN PERTUMBUHAN BIBIT CABAI MERAH (Capsicum annum L.)

The research of "the effectiveness of test of antifungal pineapple peel extract against seed-borne fungus and the growth of red chili (Capsicum annum L.) seedlings". The research aimed to determine the effect of pineapple peel extract as antifungal in controlling red chili seed- borne fungus and its effect on germination and growth of red chili seeds. The recent research was carried out using a completely randomized design non factorial consisting of 5 treatments and 5 replications. The treatment factor is concentration of pineapple peel extract consisting of without pineapple peel extract, pineapple peel extract of 10%, 20%, 30%, and 40% respectivelly. The results showed that the appropriation of several concentrations of pineapple peel extract was less effective in controlling red chili seed-borne fungi in vitro, which can be seen in the results of the observed parameters for the incidence of each pathogenic fungus in seeds and the diameter of the seed colonies. The appropriation of several concentrations of pineapple peel extract has an effect on the germination of red chili seeds in vitro, which can be seen from the results of the observation parameters that sprouts appear, but have not affected the parameters of the observation of seed germination. The appropriation of several concentrations of pineapple peel extract affected the growth of red chili seedlings in soil media, which can be seen from the results of the observation parameters of the percentage of germinated seeds, and the number of live seeds and seedlings that grew normally, but had no effect on the parameters of observation of seedling height, number of leaves seeds, plant wet weight and plant dry weight).

Proteomics of Two Thermotolerant Isolates of Trichoderma under High-Temperature Stress.

Several species of the soil borne fungus of the genus Trichoderma are known to be versatile, opportunistic plant symbionts and are the most successful biocontrol agents used in today’s agriculture. To be successful in field conditions, the fungus must endure varying climatic conditions. Studies have indicated that a high atmospheric temperature coupled with low humidity is a major factor in the inconsistent performance of Trichoderma under field conditions. Understanding the molecular modulations associated with Trichoderma that persist and deliver under abiotic stress conditions will aid in exploiting the value of these organisms for such uses. In this study, a comparative proteomic analysis, using two-dimensional gel electrophoresis (2DE) and matrix-assisted laser desorption/time-of-flight (MALDI-TOF-TOF) mass spectrometry, was used to identify proteins associated with thermotolerance in two thermotolerant isolates of Trichoderma: T. longibrachiatum 673, TaDOR673 and T. asperellum 7316, TaDOR7316; with 32 differentially expressed proteins being identified. Sequence homology and conserved domains were used to identify these proteins and to assign a probable function to them. The thermotolerant isolate, TaDOR673, seemed to employ the stress signaling MAPK pathways and heat shock response pathways to combat the stress condition, whereas the moderately tolerant isolate, TaDOR7316, seemed to adapt to high-temperature conditions by reducing the accumulation of misfolded proteins through an unfolded protein response pathway and autophagy. In addition, there were unique, as well as common, proteins that were differentially expressed in the two isolates studied.

Effect of essential oils on seed borne Fusarium sp., and seed quality of sesame (Sesamum indicum L.)

Sesame (Sesamum indicum L.) is as an important oilseed crop and seed borne fungi are reducing the yield as well as quality of the seeds produced. The present study aimed to evaluate the effect of essential oils for control of seed borne fungi as well as enhancement of seed quality of sesame. Fusarium sp., was isolated from sesame seeds by agar plate method. Four essential oils such as camphor oil, cinnamon oil, clove oil and rose oil were screened for their antifungal potential against the isolated Fusarium sp., by poisoned food method. Selected essential oils were tested at different concentrations of 100, 200, 300, 400 and 500 ppm concentrations for their ability to inhibit the mycelial growth of test fungi. All the oils completely inhibited the mycelial growth of test fungi at 500 ppm concentration. The effect of selected essential oils on sesame seed quality was analyzed by standard blotter method. All the four oils increased the germination percentage and seed vigour while the fungal infection was completely inhibited without any phytotoxic effects. Comparatively, clove oil showed the best activity followed by camphor oil, cinnamon oil and rose oil. These results observed of the essential oils indicate the possible usage of them for the sesame seed treatment following further investigations.

Soil borne Fusarium solani exhibited pathogenic effect on tomato cultivars in Nigeria

The pathogenicity of soil borne fungi Fusarium solani on tomato cultivars was relatively unclear in Nigeria. This study thus investigates the pathogenic effect of F. solani on seed germination, seedling growth and fruit of two of the most commonly consumed tomato cultivars (UC82B and Ibadan Local - IL) in Nigeria. Fusarium species were isolated from the rhizospheric soil samples of tomato cultivars and their pathogenicity was assessed using blotter and soil inoculation techniques. Out of the 26 Fusarium species isolated, 6 (23%) were morphologically (with the aid of microscope) identified as F. solani (FS1, FS9, FS10, FS17, FS21 and FS26), among which the strains FS17, FS21 and FS26 significantly inhibited (p < 0.05) germination of UC82B seed, while only FS21 was responsible for poor seed germination in IL. At the same time, FS17, FS21 and FS26 significantly reduced (p < 0.05) plumule and radicle length more in UC82B, compared to IL. At seedling stage, only FS21 manifested visible pathogenicity. Leaves and stems of UC82B were demarcated with distinct rotting and browning; wherein such symptoms were merely visible in IL. However, the fruit of both the cultivars showed variation in their respective pathogenicity range of F. solani; FS21 expressing higher level of disease severity on UC82B fruit (66.50%) compared to IL fruit (55.05%). In general, F. solani (FS21) exhibits considerable potential, both to inhibit germination of tomato seeds as well as cause diseases on seedling and fruit of tomato cultivars in Nigeria.

In vitro: stem cutting a simple technique for determination aggressive potential of fungal isolates causing root rot disease of grapevine

Pathogenic soil borne fungi causing epidemic root rot disease on grapevine and high loss of plant growth and fruit yield. Fast detection of aggressive fungal isolates is the first tool for introduce selection effective a agent for management disease progress. In vitro two simple techniques based on stem cutting of grapevine i.e., mycelial growth and cell wall degrading enzymes activities were evaluated for screening of aggressive fungal isolates in comparsion with classical pathogenicity test. Fourteen isolates of fungi associated with root rot disease of grapevine plants i.e. Fusarium oxysporumi Schlechtend, Fusarium solani (Mart.) Sacc, Botryodiplodia theobromae, Rhizoctonia solani Kuhn and Macrophomina phaseolina (Tassi) Gold. were tested and pathological action on grapevine plant (Cv.crimson) under soil artificially infested by classical method with their mycelial growth,cell wall degrading enzymes activities on stem cutting of grapevine as well as each fungal isolates of shoot and root compare the control. Fungal isolate of Botryiodiplodia theobromae No. (7) was the most isolate recorded high and significant root rot (100%) incidence and disease severity on grapevine plants followed by Fusarium avenacum isolate No. (11) and Fusarium solani isolate No. (12). Positive correlation co-efficient was observed between mycelial growth of fungal isolates tested on stem cutting of grapevine plants and root rot disease incidence and their disease severity followed by their production pectinase and cellulase enzymes. So, mycelial of fungal growth on stem cutting of grapevine is a good and simple of opportunity technique for determination aggressive degrees of fungal isolates in vitro as alternative accuracy, very short time test and very shape cost than classical pathogenicity test.

Assessment on Incidence and Severity of White Rote Associated with Agronomic Practice and Environmental Factors at North Shewa, Central Highlands of Ethiopia

White rot of garlic caused by a soil borne fungus ( Sclerotium cepivorum Berk) is a major production threat of garlic in Ethiopia and all over the world. During favorable weather conditions, and when susceptible varieties are in the production system, the disease can cause 100% yield loss. Furthermore, sclerotium cepivorum is an issue of great importance for dry climate producers. Its intensity also vary with different cultural practices and environmental factors. The study was initiated with the objectives of assessing the incidence and severity of garlic white rot associated with environmental factors and cultural practices under dry season in North Shewa, Amhara Region, Ethiopia. To assess production practices, data were collected using multistage sampling technique from 40 garlic producing households. The data necessary for the study was collected from those sampled garlic producers by using a structured interview. In each sampled producers, three quadrants (0.5m by 0.5m) 2-3 m apart were taken by making diagonal moves in the field. Then, incidence of white rot was assessed by counting the number of plants showing white rot symptoms in each quadrant and averages were taken for each field. The assessment results showed that about 97% of the fields were infested with white rot. Disease incidence was varied among districts, altitude range, temperature, soil type and field management practices. However, the mean disease incidence and severity were higher in Menz Mama Midir as compared to the other districts. Keywords : garlic, Sclerotium cepivorum , white rot, district DOI: 10.7176/JAAS/62-02 Publication date: March 31 st 2020

Seed Treatment of Capsicum annuum with Two Different Fungicides to Evaluate the Seed Germination Rate

Chili ( Capsicum annuum L. ) is the fruit of plants, the Chili is susceptible for several diseases and seed borne fungi Phytophthora capsici which produces collar rot and root of chili. Seed borne pathogens are associated with untreated seeds of chili which are also significantly reduced the germination of seed. This experiment was conducted to find out the seed borne fungi and enhanced the germination of chili ( Capsicum annuum ) with two fungicides known as Mancozeb 80% WP and Carbendazim 50% WP. Effectiveness of these two fungicides were measured when the seeds planted on blotter paper in petri plates at 27 0 C under lab conditions. These two fungicides significantly reduce the effect of seed borne fungi associated with chili seeds. Mancozeb 80% WP was found most effective to reduce the effect of seed borne fungi and increase the seed germination. Considering the results of the experiment, Mancozeb 80% WP was noted to be a best fungicide against the seed borne fungi. Keywords : Capsicum annuum , Mancozeb, Carbendazim, seed borne fungi, blotter paper. DOI: 10.7176/JBAH/10-4-04 Publication date: February 29 th 2020

FUSARIUM AND VERTICELLUM WILT IN COTTON: A REVIEW

Cotton (Gossypium hirsutum) is an important cash crop which is cultivated in more than 80 countries worldwide producing worth of 121.30 million bales in MY 2019/2020. However, it is attacked by many insect pests that causes high economic loss. Vertcillium wilt (VW) and Fusarium wilt (FW),a soil borne fungus caused by Verticillium dahlia kleb and Fusarium oxysporum f.sp. vasinfectum, is one of the most destructive diseases in cotton (Gossypium hirsutum L.) production deleteriously affecting the yield and quality in ,India and worldwide. The wilt is becoming serious problem for cotton growing farmer and key subject of research in cotton resistance genetics and pathology. This aim of this paper is to call for attention and concentrated action by describing potentially damage of the pest, morphology, symptoms, Epidemiology, behavior, entry pathways and control method. The key pest of cotton accounts for its production loss up to70% in the absence of compatible control measures. Its effective control strongly relies on integrated management strategies includes Bio control agents, Physical, cultural a virulent strains, resistant varieties are the best practices for pest management.

Effect of microbial non-volatile metabolites on growth of Fusarium oxysporum f. sp. ciceri and lini

Rhizospheric fungal antagonists activity against phytopathogen by production of volatile and non-volatile metabolites. In vitro assessments revealed their antibiosis and mycoparasitic ability to affect growth of the pathogen. Soil borne fungi, bacteria and actinomycetes were identified and used as antagonistic microbes against some soil borne pathogens. The efficacy of volatile and non-volatile metabolites produced by 14 selected dominant microbes against the common fungal test pathogens (F. oxysporum f. sp. ciceri & lini) were suppressed with colony interaction, volatile, and non-volatile metabolites emanated from different leaf surface microbes like Aspergillus niger, A. terreus, A. luchuensis, Trichoderma harzianum, Penicillium citrinum, Streptomyces rimosus, and S. aureofaciens and prior application of these antagonists effectively reduced the development of Fusarium wilt in chick pea and linseed.

Seed borne fungi of minor millet in Karnataka

Seed borne fungi of minor millet in Karnataka

Efficiency of Medicinal Plants to Control Seed Borne Fungi of Sorghum Grains

Seed-borne fungi are the most important constrained factor which causing quantitative losses, produce highly toxic and carcinogenic mycotoxins. Plant based fungicides appear to be one of the better alternatives as they are known to have minimal danger to consumers in contrast to synthetic pesticides. In view of the negative public health and economic impacts of storage fungi this study, aimed to determine the efficiency of some plant extracts for reduction or control of seed borne fungi in sorghum grains in agar plate methods. The results obtained revealed that seed treated with Olea europaea leaf extract was found the least in incidence of seed-borne fungi (50%) followed by Capsicum annuum (53.3%) in agar plate methods. Therefore, utilization of these plants as bio-control agents is recommended to reduce the proliferation of storage fungi. Keywords: plant extracts; seed borne fungi; sorghum

Rapid progression of disease in susceptible and resistant banana cultivars inoculated with Fusarium oxysporum f. sp. cubense Race 1 and Subtropical Race 4 in tissue culture

In Australia, banana tissue cultures are produced within a Quality Banana Approved Nursery Scheme (QBAN) to eliminate spread or introduction of pests and diseases such as Fusarium oxysporum f. sp. cubense (FOC) which is the current main disease threat to the Australian banana industry. Tropical Race 4 (TR4) of this persistent soil borne fungus was recently found in the major production area of North Queensland and attacks the commercial Cavendish cultivar ‘Williams’. Growers want evidence that FOC will not be carried in banana tissue culture and will not be suppressed due to culture conditions or an immune cultivar. To determine how FOC would grow in banana tissue cultures, two-week-old banana tissue cultures growing in Murashige and Skoog media were inoculated with FOC under commercial conditions, to determine survival of plants and rate of disease development. Tissue cultures of cultivars ‘Lady Finger’, susceptible to Race 1 (R1) and Subtropical Race 4 (STR4), ‘Williams’, immune to R1 but susceptible to STR4, and ‘Goldfinger’ immune to R1 and highly tolerant to STR4 were inoculated with R1 and Subtropical Race 4 FOC. Within three days the Fusarium had grown to cover more than 50% of the culture surface and within 10 days 100% of FOC inoculated cultures were fully colonised and within 2-3 weeks all plants were dead. All non-inoculated plants remained healthy. Both FOC Races grew rapidly in tissue culture with fluffy white mycelia covering the surface of media and plants. Fusarium growth was not restricted in banana tissue culture, where growth was rapid and very obvious. In all cultures inoculated with any FOC Race, the banana plantlets were rapidly invaded and killed, regardless if that cultivar was resistant to FOC under field conditions. Fusarium can be easily detected in banana tissue culture and rapidly kills plantlets before completion of one subculture cycle.

Evaluation of seed-borne fungi associated with tomato and their control measures

A number of seed borne fungi such as- Fusarium moniliforme, Curvularia lunata, Alternaria solani, Helminthosporium solani, Aspergillus flavus, A. niger and Penicillium spp. were identified from the selected BARI-8, Nilima, Patharkuchi, Roma and Ratan varieties of tomato seeds. The highest (2.53%) mean incidence of the fungi F. moniliforme were recorded in tomato variety Roma, BARI-8, Nilima and Ratan while the lowest (0.13%) mean incidence of the fungi Penicillium was found in Ratan. The maximum percent of germination (64%) was recorded in both BARI-8 and Patharkuchi varieties, while the minimum (7%) germination in Nilima. The highest seedling vigor index (632.96) was encountered in BARI-8 and the lowest in Nilima. Trichoderma viride, T. harzianum and T. koningii were used as bio-control agents against major seed borne fungi. T. viride showed the significantly effective mycelial growth inhibition against F. moniliforme and C. lunata, while T. harzianum and T. koningii showed poor performance against both tested fungi. In case of botanical extracts, Lawsonia inermis exhibited the maximum (82.15% and 86.24%) inhibition of mycelium growth of F. moniliforme and C. lunata, respectively. Chemical fungicides, Bavistin (0.5 gm/l) inhibited 65% mycelial growth against F. moniliforme, while higher concentration of chemical fungicide gave 81% inhibition of C. lunata. The results suggested that, L. inermis phytoextract can possibly be exploited for the management of seed-borne pathogenic fungi of tomato in an environmental friendly way.Jahangirnagar University J. Biol. Sci. 6(2): 59-66, 2017 (December)

Effect of Plant Extracts on Seed Borne Fungi of Jute

The aim of this study was to determine the prevalence of seed-borne fungal pathogens of jute and their control with plant extract. The experiment was carried out in seed pathology centre, Bangladesh Agricultural University to obtain relevant information about the health of jute seeds and find out the efficacy of extracts as seed-treater. Two varieties viz., Deshipat (Corchorus capsularis) and Tossapat (Corchorus olitorius) were selected for this study and jute seeds were collected from two different locations of Bangladesh. The major predominant identified fungi were Colletotrichum corchori, Macrophomina phaseolina, Fusarium spp., and Botryodiplodia theobromae. Least seed-borne fungi were found in the variety of Tossapat. Low germination of seeds was found related to high prevalence of seed-borne fungal infections. Highest seed-borne infection was obtained in the variety of Deshipat. In this study, we evaluated some major plant extracts such as garlic clove (Allium sativum), neem leaves (Azadirachta indica), allamanda leaves (Allamanda cathartica L.) and marigold leaves (Tagetes spp.) for observing the action of these plant extracts on seed borne fungi of Jute. The study revealed that the extract of Garlic (Allium sativum), and Biskatali (Polygonum hydropiper) increased the germination of seeds and garlic (Allium sativum) extract was also found to be most effective in controlling the seed-borne infection among all the treatments. Although the inhibiting capacity of the extracts of Allamanda (Allamanda cathartica L.) and Biskatali (Polygonum hydropiper) was found to be similar and Biskatali extract was found to have the second position among all the treated plant extracts in inhibiting the growth of isolated fungal pathogens.

How Does Storing Containers on Farmers Stored Boro Rice Seed Affect the Seed Qualities?

The experiment was conducted at Laboratory of Plant Pathology, Bangladesh Agricultural University (BAU), Mymensingh and Seed Pathology Centre, BAU, Mymensingh during 2010 to 2014 to investigate the effect of storing containers on moisture content, germination percentage, seedling vigor, apparently healthy of seeds and infection of rice stored seeds. The rice seed samples of cv. BR14, BRRI dhan28, BRRI dhan29 and Guti were collected from 36 farmers belonging to the individual villages at Ishwarganj Upazila under Mymensingh District. Four types of storing containers were used by farmers own selves following traditional practices. Storing containers were gunny bag lined with polythene, bamboo bin lined with polythene, gunny bag and earthen pot locally called motka. The highest percentage of moisture content was in gunny bag (14.32%) and the lowest in gunny bag lined with polythene(12.59%) similarly best germination was in gunny bag lined with polythene (78.04%) and worst in motka (65.16%) consequently maximum vigor index was shown in gunny bag lined with polythene (1756) and minimum in motka (1458). The experiment also found the highest percentage of apparently healthy seeds in gunny bag lined polythene (55.01%) and lowest in motka (46.42%).Sequentially maximum seed borne fungi infection occurred in gunny bag (28.98%) and minimum infection in bamboo bin lined with polythene (22.70%). The result of the experiment evidently proved that polythene sheet was the key indication to protect the quality of seeds. On the other hand, the earthen pot or motka was the worst material to deteriorate the quality of seeds during storing time.

FUNGAL DIVERSITY ASSOCIATED WITH PEARL MILLET PENNISETUM GLAUCUM L.) GRAINS FROM TAIZ GOVERNORATE, YEMEN AND THEIR AMYLASE PRODUCTION

In Yemen, this is the first record on fungal diversity associated with millet grains. Grain- borne fungi were tested for NaOCl- treated and non- treated samples of millet grain collected from Taiz Governorate, Yemen using direct plate method on Czapek’s (Cz) and Czapek’s supplemented with 40% sucrose (Cz40S) agar media. A total of 48 species belonging to 20 genera were isolated. The highest count and number of genera and species were recorded in non- treated grains on Cz40S medium. This means that the majority of fungi associated with grains were osmotolerant/osmophilic. The highest frequencies were represented by Aspergillus flavus, A. niger aggregate, A. vadensis, Eurotium amstelodami, Pencillium duclauxii and Rhizopus stolonifer. Among 109 isolates screened for their ability to produce amylase enzyme, 81.65% could produce the enzyme, of which Aspergillus homomorphus (a new record in Egypt), Emericella nidulans, Fusarium oxysporum and Penicillium griseofulvum were the best producers. Hence, these fungi may cause degradation of cell walls and spoilage of grains. Moreover, it is important to determine which organisms might be associated with seeds and grains in storage causing quality loss through their growth and enzyme production. The early detection of these organisms is required to prevent their harmful effects.

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

Evaluation of Antifungal Activities of Extracts of Aegle marmelos, Syzygium cumini and Pongamia pinnata against Pythium debaryanum

The present study dealt with the assessment of antifungal activities of acetone, ethanol, methanol and chloroform leaf and fruit extracts of Aegle marmelos, Syzygium cumini and Pongamia pinnata against the soil borne fungi, Pythium debaryanum. Maximum inhibition of fungal growth was found with methanol extract of A. marmelos leaves and fruits. At 1 ml concentration (C4), complete inhibition of mycelial growth of P. debaryanum was observed with extract S3P1 (100%), followed by S3P3 (97.63%) and S2P1 (95.21%). Lowest inhibition was oberved with S4P2 (75.40%). Pot culture study revealed that tomato seed treatment with Pseudomonas fluorescens (10 g/kg)+Trichoderma viride (4 g/kg)+methanol extract of A. marmelos 4% was effective to control pre and post emergence damping off caused by P. debaryanum. The methanol extract revealed strongest antifungal activity against P. debaryanum, followed by ethanol extract and lowest antifungal activity was found in chloroform extract.

English

The experiment was conducted with three replication in randomized complete block design in field laboratory of Department of Agronomy, Bangaladesh Agricultural University, Mymensingh. Extracts of garlic (Allium sativum) and neem (Azadirachta indica), BAU-Biofungicide (Trichoderma based preparation) and Proud (Propiconazole) and Bavistin (Bavistin DF) were evaluated under field condition in controlling brown spot disease Bipolaris oryzae (Breda de Haan) Shoem of rice cv BRRI dhan28. Foliar spray of BAU-Biofungicide (2%) and Proud (0.1%) showed profound effect in marked reduction of disease severity. BAU-Biofungicide (2%) resulted grain yield 5785 kg/ha in the field and reduction in cost of production was found with benefit-cost ratio (BCR). BCR 2.78:1 was achieved in BAU-Biofungicide (2%) which is close to 2.87:1 in Proud (0.1%). Highest (98.00%) germination percentage was observed with BAU-Biofungicide (3%) as well as maximum (35.64%) increase of vigour index was found with Proud (0.1%) over control. BAU-Biofungicide and Proud were found to have in inhibiting seed borne fungi when they were applied as foliar spray. Trichoderma harzianum was associated with B. oryzae infected seeds and when kept for few days for incubation it overgrew B. oryzae. Key words: BAU-Biofungicide, Bipolaris oryzae, benefit-cost ratio (BCR), disease severity, seed borne fungi, vigour index.