Genetic Testing of Inbred Lines and Single Cross Hybrids against Fusarium Stalk Rot Caused by Fusarium moniliforme in Maize (Zea mays L.)

Globally, Maize (Zea mays L.) is a third major cereal food crop. It is a multipurpose crop with 26% of its production is used as food by human beings. Maize is known as “queen of cereals”, because of its high genetic yield potential, efficient utilization of radiant energy and wider adaptability. About 65 different phytopathogens affect the maize production in different stages of life cycle. Among which Fusarium moniliforme is one such soil borne pathogen causes Fusarium stalk rot (FSR) disease that ultimately reduces maize yield potential over the world. In any breeding program, screening and genetic testing of available germplasm resources against pathogens is necessary to prevent yield losses. Hence, the present research screened around 114 maize inbred lines and 45 single cross hybrids (SCHs) against FSR under artificial epiphytotic conditions. Among 114 inbreds, only four inbreds viz., CM 202, 10878, MAI-759 and MAI-766 (mean disease score of 3-4) showed moderately resistant reaction and out of 45 SCHs, only one hybrid combination i.e., MAI329 × CM202 (mean disease score was 2.60) exhibited resistance reaction against Fusarium stalk rot. Nevertheless, these resistance sources could be utilized in maize breeding programs for obtaining high yielding cultivars with resistance towards FSR disease.

UJI DAYA TUMBUH DAN UJI VIRULENSI JAMUR PATOGEN Fusarium moniliforme PENYEBAB PENYAKIT POKAHBUNG PADA TANAMAN TEBU (Saccharum officinarum)

Pokahbung merupakan salah satu penyakit penting yang banyak ditemukan di pertanaman tebu dan disebabkan oleh jamur Fusarium moniliforme. Penelitian ini bertujuan untuk menguji daya tumbuh F. moniliforme di 6 media yang berbeda dan mengetahui media yang sesuai bagi pertumbuhan jamur F. moniliforme serta mengkaji pengaruh perbedaan media pertumbuhan jamur yang digunakan terhadap tingkat virulensi F. moniliforme pada tanaman tebu. Penelitian dilaksanakan di Laboratorium Penyakit Tumbuhan dan Rumah Kaca (Greenhouse), Fakultas Pertanian, Universitas Brawijaya, Malang. Metode penelitian ini menggunakan teknik purposive sampling dan eksperimen. Eksperimen dilakukan menggunakan Rancangan Acak Lengkap (RAL) dengan 6 perlakuan media yang berbeda dan 4 kali ulangan secara In vitro dan In vivo. Hasil penelitian menunjukkan bahwa dari parameter pengamatan diameter koloni, kerapatan konidia, dan viabilitas konidia menunjukkan hasil yang tidak berbeda nyata. Sehingga kentang, umbi ganyong, dan ubi kayu dapat digunakan sebagai media pertumbuhan jamur F. moniliforme dan penggunaan media kentang dan dextrose serta media kentang dan sukrosa dinilai dapat menjadi media yang paling efektif untuk pertumbuhan jamur F. moniliforme. Perkembangan intensitas serangan penyakit yang ditimbulkan dari keenam media yang berbeda memiliki tingkat virulensi yang sama.

Production of gluconic acid by fungal species isolated from soil in Keffi, Nigeria

This investigation aimed at production of gluconic acid by fungal species isolated from soil in Keffi. Standard microbiological methods were employed for isolation and identification of the fungal isolates. The yields of gluconic acid produced by the different isolates of the fungi were determined using gas chromatograph and mass Spectrometry. The occurrence of fungi showed that Rhizopus oryzae was 100%, Aspergillus carneus was 75.0%, Aspergillus niger was 75.0% and Aspergillus terreus was 100% while Trichoderma viride was 25.0% and Fusarium moniliforme was 25.0%. The result further demonstrated that three species of the fungal isolates Aspergillus niger, Aspergillus carneus and Fusarium moniliforme were found to produce gluconic acid. Screening for gluconic acid production showed that Aspergillus carneus isolated from locations As1, Cs1 and Cs2, Aspergillus niger isolated from locations Bs1, Bs2 and Cs4 were able to produce gluconic acid. Result of effect of temperature, pH, substrate concentration and fermentation time on production of gluconic acid showed that Aspergillus niger Bs2 produced highest amount of gluconic acid at 28oC, similarly highest amount for gluconic acid produced by Aspergillus carneus As1 was at 28oC, whereas Fusarium moniliforme Bs4 produced highest at 30OC. pH 6.5 was found to the best optima pH for production of both gluconic acid for the fungi studied namely Aspergillus niger Bs2 and Aspergillus carneus As1 and Fusarium moniliforme Bs4 produced highest gluconic acid at pH 5.5. The substrate concentration showed highest production of gluconic acid was produced by Aspergillus niger Bs2 at substrate concentration of 25%. Aspergillus carneus As1 produced highest at substrate concentration of 20% and Fusarium moniliforme Bs4 produced highest at substrate concentration of 20%. The fermentation time showed highest production of gluconic acid by Aspergillus niger Bs2 and Aspergillus carneus As1 was after 144 hours whereas F. moniliforme Bs4 produced gluconic acid after 120hrs respectively. The fungi species isolated from soil in keffi revealed great ability in production of gluconic acid.

Characterisation of Plant Growth-Promoting Endophytic Bacteria from Sugarcane and Their Antagonistic Activity against Fusarium moniliforme

The use of endophytic bacteria in agriculture provides an effective way of improving crop yield and significantly reducing chemical usage, such as fungicides. This research was conducted to explore endophytic bacteria with plant growth promotion (PGP) and antifungal activities against Fusarium moniliforme AIT01. In this study, we obtained 52 isolates of endophytic bacteria associated with the roots and stems of sugarcane from Nakhon Ratchasima province, Thailand. In vitro antagonistic activity test showed that 14 out of 52 isolates had antagonistic activity against the fungal pathogen F. moniliforme AIT01. These antagonistic endophytic bacteria were identified as belonging to six different species as follows: Nguyenibacter vanlangensis, Acidomonas methanolica, Asaia bogorensis, Tanticharoenia aidae, Burkholderia gladioli and Bacillus altitudinis based on phenotypic characteristics, along with phylogenetic analysis of their 16S rRNA gene sequences. Seven isolates effectively inhibited F. moniliforme AIT01 mycelial growth by up to 40%. The volatile compounds of six isolates reduced the growth of F. moniliforme AIT01 by over 23%. Moreover, riceberry rice seedlings previously treated with B. gladioli CP28 were found to strongly reduce infection with phytopathogen by 80% in comparison to the non-treated control. Furthermore, the isolates also showed relevant PGP features, including ammonia production, zinc and phosphate solubilisation, auxin and siderophore biosynthesis. These results demonstrated that the tested endophytic bacteria could be successfully utilised as a source of PGP and biocontrol agent to manage diseases caused by F. moniliforme.

Production of amylases by some aspergillus and fusarium species isolated from waste corncobs in Keffi, Nigeria

Amylases are important industrial enzymes that have wide applications ranging from conversion of starch to sugar syrups, to the production of cyclodextrins for the pharmaceutical industry. This investigation aimed at production of amylases using Aspergillus and Fusarium species isolated from waste-corncobs in Keffi Nigeria. Standard microbiological methods were employed for isolation and identification of the fungal isolates. The yields of amylases produced by fungi isolates were determined using Spectrometry. The isolation rate of Aspergillus and Fusarium species was high in location A, C and D with 60% and location B with 40%. The percentage occurrence of the isolates demonstrated that Aspergillus carneus was 40%, Aspergillus aculeatus was 60% and Aspergillus flavus was 20% while Fusarium moniliforme was 80% and Fusarium redolens was 40%. The result demonstrated that three species of the fungal isolates Aspergillus aculeatus, Aspergillus carneus and Fusarium moniliforme were found to produce amylases. Aspergillus aculeatus isolated from locations C3, D1 and D2 produced 0.018mg/ml, 0.018mg/ml and 0.016mg/ml amylases respectively. Similarly, Aspergillus carneus isolated from locations A1 and B2 produced 0.021mg/ml and 0.012mg/ml amylases. Fusarium moniliforme isolated from locations A3, C1 and C4 produced 0.010mg/ml, 0.016mg/ml and 0.015mg/ml amylases. Result of effect of (temperature, pH and fermentation time) for production of amylases. Whereas highest amount for amylases produced by Aspergillus aculeatus and F monliforme were produced at 28 OC. pH 5.0 was found to the best optima pH for production of amylases from the fungi studied A. carneus (2.99 mg/ml amylases). The fermentation time showed highest production of amylase by A. carneus and A. aculeatus after 72 hours while F. moniliforme produced at 96hours. The fungi species isolated from soil in keffi can be used for production of amylases.

Effects of Trichoderma harzianum Fertilizer on the Soil Environment of Malus hupehensis Rehd. Seedlings under Replant Conditions

A pot experiment was performed to investigate the effects of Trichoderma harzianum on the root morphology of Malus hupehensis Rehd. seedlings and their soil environment under replant conditions. The experiment consisted of four treatments: continuously cropped soil (CK1), methyl bromide fumigation (CK2), carrier substrate control (T1), and T. harzianum fertilizer (T2). Plant growth parameters, soil phenolic acid content, abundance of soil microorganisms, and root respiration rate were measured. Compared with CK1, plant height, basal diameter, and fresh weight were 34.58%, 27.55%, and 32.91% greater in T2; 11.35%, 12.10%, and 18.33% greater in T1; and 54.34%, 57.64%, and 45.74% greater in CK2. These metrics were significantly higher in the CK2 treatment than in the other treatments. The second highest values were recorded in the T2 treatment. Differences in root architecture were consistent with differences in biomass. Application of T. harzianum fertilizer was associated with increases of 45.45%, 120.06%, 86.44%, and 268.29% in the activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), respectively, and there was little difference between T2 and CK2. The contents of phlorizin and phloretin were 39.39% and 51.70% less in T2, respectively, and 17.85% and 18.14% less in T1, respectively, compared with CK1. Trichoderma harzianum fertilizer increased the abundance of bacteria and actinomycetes while decreasing that of fungi. The gene copy numbers of Fusarium oxysporum and Fusarium moniliforme were 64.30% and 49.35% less, respectively, in the T2 treatment. The fungus population and the gene copy number of Fusarium oxysporum and Fusarium moniliforme was the least in CK2 because of the good sterilization effect. The T. harzianum fertilizer showed satisfactory effects in promoting the root growth of M. hupehensis, increasing the root resistance, decreasing the soil phenolic acid content, and significantly reducing the gene copy number of F. oxysporum and F. moniliforme. In summary, T. harzianum fertilizer is an effective and green alternative for the prevention and control of apple replant disease (ARD).

Transmissibilidade do Fusarium moniliforme em sementes de milho sob diferentes períodos de exposição

O Fusarium moniliforme é o principal patógeno associado a sementes de milho no Brasil. É considerado um dos principais responsáveis pela deterioração de sementes, morte de plântulas, podridão de radículas, podridão de colmo e podridão da espiga e dos grãos. Objetivou-se no presente estudo avaliar a transmissibilidade do fungo Fusarium moniliforme em sementes de milho sob diferentes períodos de exposição (0, 24, 48 e 72h) das sementes. O delineamento experimental contou com cinco repetições e quatro tratamentos para cada fator avaliado, adotado o delineamento inteiramente casualizado. O fungo foi obtido da coleção micológica do Laboratório de Fitopatologia do Centro Universitário Católica do Tocantins e foram inoculadas por meio da deposição das sementes sobre o micélio do fungo. Utilizou-se o teste de sanidade de sementes e o teste de germinação em rolo de papel. O tempo de exposição influenciou significativamente (p<0,05) sobre a incidência do fungo, de modo que, às 48 horas o patógeno já havia infestado 100% das sementes. A taxa de germinação foi influenciada negativamente pela presença do fungo, entretanto, sementes expostas ao patógeno por 24, 48 e 72 horas apresentaram taxas germinativas semelhantes estatisticamente (p>0,05). Conclui-se que o período mínimo de 24 horas de contato das sementes de milho com Fusarium moniliforme foi suficiente para a ocorrência de infecção reduzindo o desempenho germinativo dos lotes de sementes.

Mycoflora associated with diseased rice grains in Bangladesh and their pathogenic potentiality

Fifty six spotted rice grain samples of four commercially cultivated rice varieties namely BRRI 28, 29, Kalijira and Pajam were collected from 14 different districts of Bangladesh. Forty rice samples (Hybrid 2,3,4, BR7,11,12,14,16,22,23,25,26and BRRI28 to BRRI 55) were also collected from Bangladesh Rice Research Institute at Joydevpur. Twenty-fivespecies of fungi belonging to 15 genera were associated with these rice varieties. The isolated fungi were Alternaria alternata, Aspergillus clavatus, A. flavus, A. fumigatus, A.niger, A. ochraceus, A.oryzae, A. terreus, Chaetomium globosum, Cladosporium cladosporioides, Colletotrichum gloeosporioides, Curvularia lunata, C. lunata var. aeria, Drechslera oryzae, Fusarium moniliforme, F. oxysporum, F. solani, Microdochium oryzae, Nigrospora oryzae, Penicillium spp., Pestalotiopsis guepinii, Sarocladium oryzae and Trichoderma viride. Amongst these fungi nine i.e. Alternaria alternata (Fr.) Keissler, Aspergillus flavus Link, Curvularia lunata (Wakker) Boedijn, Drechsler aoryzae Breda de Haan (Subramanian and Jain), Fusarium moniliforme Sheldon, F. solani (Mart.) Sacc., Microdochium oryzae (Hashloka and Yokogi) Sam. and Hal., Pestalotiopsis guepinii (Desm.) Stay. and Sarocladium oryzae (Sawada) W. Gams and D. Hawks were found to be pathogenic to rice seeds. The most predominant fungus was D. oryzae which was followed by A. flavus and the least incidence was observed in case of F. solani and P. guepinni. Bioresearch Commu. 7(1): 932-940, 2021 (January)

Prevalence and Transmission of Fusarium moniliforme: A Seed Borne Pathogen of Rice

Fusarium moniliforme is one of the major seed borne pathogen of rice in Bangladesh that causes significant yield loss. To observe the incidence and transmission of this pathogen, farmers saved seeds and seeds from BADC were collected and the pathogens were detected by blotter method. The prevalence of the F. moniliforme varied according to locations and seasons. The highest 18% of seed infection was recorded in Boro seeds of Netrakona district and the lowest 2% was in Gazipur district. The Embryonal end of the seed is the most preferable site of the infection. F. moniliofrme successfully transmitted from seed to seedling and the transmission is high when pre- sprouted seed sown on the puddled seed bed. The study recommended that before planting season, seeds should be tested and treated when necessary to minimize spread of the pathogen. Bangladesh Rice J. 24 (1): 11-19, 2020