Identification of seed-borne fungi of farmer-saved seeds of pepper and their control with some selected botanicals

A survey was conducted on the source of planting materials and pre-planting seed treatment practice by pepper farmers in Obenemasi and Ofoase-Kokoben communities in the Ashanti Region of Ghana using a well-structured questionnaire in June, 2011. Seed health test was conducted on 40 farmer-saved pepper seed samples collected from the farmers interviewed using the blotter method in the laboratory. Efficacy of garlic, ginger and neem botanical extracts in managing the seed-borne fungi of pepper seeds was also investigated in this study in-vitro. Results of the questionnaire-based survey indicated that, majority of respondent farmers, about 75% recycled seeds from previous harvest, 20% of respondents also used seeds obtained from friends and 5% obtained their pepper seeds from local markets. Nine genera of fungi including 12 species were identified from the pepper seed samples collected. The three botanical extracts proved effective as Mancozeb in controlling one or more of the test seed-borne fungi. Garlic aqueous extract (60% (w/v)) was effective as Mancozeb in controlling Colletotrichum capsici and Colletotrichum gloesporioides. Ginger aqueous extract (60% (w/v)) was also effective against seed-borne Fusarium and Aspergillus spp. whereas aqueous neem extract (60% (w/v)) was effective in controlling Aspergillus flavus and Aspergillus niger.

Occurrence of Anthracnose Disease of Turkey Berry (Solanum torvum) at Bunso, Eastern Region, Ghana

Aims: To identify the causal agent of anthracnose disease of Solanum torvum, determine whether the pathogen is seedborne and also to ascertain the cross infection potential of the pathogen on other Solanaceous crops of economic importance. Place and Duration of Study: Bunso, in the East Akim District of the Eastern Region of Ghana, between January and October, 2017. Methodology: The disease symptoms on matured fruits, leaves, stems and flowers of Solanum torvum were carefully observed for documentation with magnifying glasses and the naked eyes. The pathogen was isolated on PDA after incubation for five days and the identification was based on the colony, morphology and conidial characteristics with reference to laboratory manuals. The virulence of the fungal isolates from the S. torvum fruits was determined through pathogenicity tests. A seed health test was conducted in accordance with the International Seed Testing Association (ISTA) to determine whether the pathogen is seedborne. Conidial suspension of Colletotrichum acutatum (1×103 per ml) was used to inoculate pepper and eggplant fruits in a cross infectivity test. Results: Colletotrichum acutatum was repeatedly isolated and identified as the causal agent of the disease on the fruits and was also seedborne. In cross infectivity studies, the pathogen produced characteristic anthracnose symptoms on both eggplant and pepper which happens to belong to the same Solanaceae family just as the turkey berry. Conclusion: The anthracnose disease of Solanum torvum at Bunso, in the Eastern Region of Ghana is caused by Colletotrichum acutatum that has the potential to cross infect other Solanaceous species. This study is the first scientific report of the occurrence of anthracnose disease of S. torvum in Ghana.

Essential oils of Tahiti lemon and cinnamon bark in control of storage fungi and the physiological and sanitary quality of beans

ABSTRACT: With the objective to evaluate the efficiency of essential oils of Citrus latifolia (Tahiti lemon) and Cinnamomum zeylanicum (cinnamon bark) in the control of plant pathogens Penicillium sp. and Aspergillus sp. and the quality of the bean seeds, two experiments were conducted. In the first one, the effect of essential oils of C. latifolia and C. zeylanicum was evaluated in vitro development of the fungi Penicillium sp. and Aspergillus sp. and, in the second one, the influence of essential oils on the physiological and sanitary quality of bean seeds. The variables mycelial growth, conidial germination and sporulation of Penicillium sp. and Aspergillus sp. were measured in the first experiment, while the seed germination test, first count of germination, germination speed index (GSI) and sanity test of bean seeds were measured in the second. The essential oil (EO) of C. zeylanicum was more efficient than C. latifolia in the control of Aspergillus sp. and Penicillium sp., but decreased the physiological quality of the beans seeds. The fungal diversity identified in the seed health test was composed by fungi of the genera Aspergillus, Penicillium, Cladosporium, Fusarium, Chaetomium and Rhizopus. The results indicate the potential of the use of these EOs in the seeds treatment.

Physiological maturity and drying speed in the quality of zucchini ( Cucurbita pepo L.) seeds

Harvesting and drying are essential procedures to obtain high quality seeds as well as for their conservation during storage. The goal of this research was to identify the physiological maturity stage and to verify the effect of drying speeds on the quality of zucchini seeds. A completely randomized design in a 3x2x2 factor scheme was used, involving three fruit maturation stages (49, 56 and 63 days after anthesis - DAA), two drying speeds (slow and quick) and two storage periods (0 and 6 months). Seed quality was evaluated by germination, first count, accelerated aging, electrical conductivity, tetrazolium, seedling emergence, emergence speed index and seed health test. Moisture content, thousand seed mass and percentage full seeds were also evaluated. Zucchini seeds reach maximum quality at 49 DAA. Slow or quick drying and storage do not affect the physiological quality of seeds that were harvested at 49 DAA. The delayed harvest of fruits reduces the quality of seeds. Quick drying reduces the incidence of the fungi Alternaria, Cladosporium, Phoma and Fusarium, and increases the occurrence of Aspergillus and Penicillium.

Accelerated aging parameters in the prediction of physiological and sanitary quality of birdsfoot trefoil (Lotus corniculatus L.) seeds

The objective of this study was to evaluate the accelerated aging test, with and without NaCl solution, predicting the physiological health and quality of birdsfoot trefoil (Lotus corniculatus L.) seed. The experimental design was completely randomized. Ten seed lots were submitted to three conditioning periods (24, 48 and 72 h at 41 ºC). The physiological characterization of the lots was the determination of water content (before and after accelerated aging), germination, first germination count, germination speed index, seedling emergence and seed health test. The data were submitted to variance analyze and the averages were compared by the Scott-Knott test, at 5% probability. The accelerated aging methodologies with saline solution and saturated NaCl solution, conditioned for 48 h, were correlated with seedling emergence test (0.52 and 0.69, respectively), allowing the prediction of physiological quality of birdsfoot trefoil seeds. The use of saturated solution for 48 h decreases incidence of fungi. The traditional method is not suitable because it provides water content variation between samples above the tolerable.

Control of seed borne fungi on tomato seeds and their management by botanical extracts

Seed health test was done in laboratory to determine the status of seed borne fungi on seeds of five tomato (Lycopersicon esculentum) varieties viz. Manik, Ratan, Roma VF, Kopotakkho and Monirumpuri and their possible control by using plant extracts. A total of 4 genera of 3 species of fungi were recorded where Fusarium oxysporum was the most prevalent and predominant seed borne fungus (25.60%). Other three fungal species are Aspergillus sp. of Aspergillus flavus (21.70%) and Aspergillus niger (11.11%) and Cladosporium sp. (13.49%). Tomato seeds were treated with different plant leaf extracts namely Mahogany, Mehendi and Allamanda with different doses viz. 1:1, 1:2 and 1:3 to control the seed borne fungi. In treated seeds, germination was ranged from 72-82% which was 68% in controlled condition. Among the doses of three botanicals, Mahogany, Mehendi and Allamonda extract @ (1:1 w/v) showed significant performance in controlling seed borne fungi and germination of tomato seeds. Among the three botanicals, Mahogany @ (1:1 w/v) was found the best treatment regarding percent reduction of seed borne infection.Res. Agric., Livest. Fish.3(3): 403-410, December 2016

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

PHYSIOLOGICAL AND SANITARY QUALITY OF DESICCATED AND STORED AZUKI BEAN SEEDS

ABSTRACT: The objective of this research was to evaluate the effects of using different herbicides as desiccants in pre-harvest and the effects of storage on the physiological and sanitary quality of azuki bean seeds (Vigna angularis Willd). The experiment was arranged in a randomized complete block design in a split plot scheme, with four replications. Four herbicides were tested: paraquat (400 g a.i. ha-1), glufosinate ammonium (400 g a.i. ha-1), glyphosate (720 g a.i. ha-1), flumioxazin (30 g a.i. ha-1) and a control without herbicide application. In the subplots seed quality was tested in two evaluation periods: at harvest and six months after harvest. Desiccant was applied when the azuki beans were physiologically mature. We assessed the physiological and sanitary quality of the seeds using a vigour and seed health test. The use of glyphosate resulted in a higher incidence of abnormal seedlings and reduced size and weight of the seedlings. With paraquat and flumioxazin the physiological quality was maintained and there was reduced pathogen infestation in the seeds six months after harvest. Storage affected the physiological quality of the azuki bean seeds.

Seed treatment for improving quality of hybrid seeds of rice

Seeds of 15 hybrid rice varieties viz. Durber, Agomoni, Meghna, Hybrid super, Moyna, Tia, Gold, Aloron, Jagoron, Suborno, Safollo, Hira-1, Hira-2, Hira-4 and Hira-6 were collected from five different seed producing companies of Bangladesh. BAU-Biofungicide (3%), extracts of Garlic (1:1), Allamanda leaf (1:1) Bavistin (0.3%), Thiovit ( 0.3%) and Provax (0.3%) were used for treating seeds to improve quality of hybrid seeds of rice. The moisture content of seed samples ranged 12.20% to 14.37%, where highest moisture content was found in variety Meghna and lowest in variety Moyna. 1000-seed weight of seed samples ranged from 20.00 to 26.00g, where highest weight was recorded in Hira-4 and lowest was recorded both in Aloron and Hira-1. Seed health test revealed 11 different seed borne fungi viz. Bipolaris oryzae (0.0 to 25.5%), Fusarium moniliforme (0.00 to 3.0%), Fusarium oxysporum (0.0 to 18.0%), Aspergillus flavus (0.00 to 11.0%), Aspergillus niger (0.00 to 5.0%), Aspergillus candidus (0.00 to 15.0%), Penicillium spp. (0.0 to 7.0%) , Alternaria padwickii (0.0 to 1%), Alternaria tenuis (0.0 to 11.0%), Curvularia lunata (0.0 to 40.0%) and Nigrospora oryzae (0.0 to 4.0%) . Germination test resulted normal seedlings from 26.00 to 97.00%, where highest was recorded in variety Jagoron that treated with BAU-Biofungicide resulting highest increase in number of normal seedlings by 239.28% over untreated control. BAU-Biofungicide significantly decreased (upto 90.00%) formation of abnormal seedlings over untreated control. Moreover, BAU-Biofungicide increased up to 713.78% Vigor index over untreated control.Asian J. Med. Biol. Res. December 2015, 1(3): 406-415

Quality of maize seeds harvested and husked at high moisture levels

Harvest of maize seeds with high moisture levels has been recommended; nevertheless, after harvest, the ears undergo the process of husking and there is a need to assess the compatibility of these processes. The purpose of this study was to assess the effects of mechanical husking on the quality of maize seeds collected at high moisture levels. Dent BM 3061 hybrid maize seeds, manually collected from the ear, with moisture contents of 45%, 40% and 35%, and a 20/64 round sieve were used. The ears were mechanically husked (CWA machine, 312 rpm), dried in a stationary drier at 35 ⁰C until reaching 22% moisture, followed by drying at 42 ºC until reaching 12%. Then, they underwent shelling, followed by a chemical treatment with Maxin® + K-obiol® + Actellic®. Seed quality was assessed according to the occurrence tests of mechanical damage, first count, germination, seedling emergence, emergence speed index, average emergence time, electrical conductivity, accelerated aging, cold test, and seed health test at every quarter for 9 months. The mechanical husking affects maize seed quality, depending on the degree of seed moisture at harvest and on the material studied. This hybrid's seeds can be collected with seed moisture levels at 40% with the use of mechanical husking.