Plant materials Fresh diseased free leaves and fruits of twelve plant species were collected from Kaligonj Thana under Jhenidah district of Bangladesh and Botanical Garden of Bangladesh Agricultural University, Mymensingh, Bangladesh. A voucher specimen of plant images has been deposited in the author scientific album and all extracts are also deposited in the refrigerator of M.S Laboratory, Department of Plant Pathology Bangladesh Agricultural University, Mymensingh, Bangladesh.
Aqueous extracts Green leaf and fruit samples (100g) of different plants were collected and washed very carefully with distilled water. Then the plant parts are ground with conventional grounder called “HAMAN DISTA” (mortar and pastels) which is available and popular in Bangladeshi farmers’ family. Then the grounded materials were dipped into 100ml distilled water for 48 hours for complete extraction of the active ingredient from the extracted samples. After that, the water and ground materials were filtered with the help of a very fine and clean piece of cloth separately for every plant species. In every time after separation, the cloth is washed with antibacterial soap carefully followed by washing with distilled water. Then, the crude extracts were preserved in glass bottles in a refrigerator at 5 ± 2ºC for further use. This indigenous methodology was practiced to justify the effectiveness of this method, so that the poor farmers of our country would practice this method in their house without facing any technological troubles for preparing a plant extracts for using in their own field crops. The authors tried to make this methodology which too easy and practice without any kind of scientific gorgon to the illiterate person in the country.
Test fungi Farmers’ stored Brinjal (Solanum melongena) seeds were collected from the farmers’ house. The tested seeds were not treated with any seed treating chemicals. Then seeds were placed in blotter method and placed in incubation at 22 ± 2 ºC for growth of fungi. After 10 days pletting of seeds the growth of seed borne fungi on the seeds were recorded. Then the infected seeds are marked and placing in the Potato Dextrose Agar (PDA) medium. After that, the inocula of fungi are growing in the PDA medium. Lastly, the individual inoculum was isolated and set in PDA medium for pure culture. After 5 days of inoculation, the individual pathogenic fungi were identified by Stereomicroscope with the specific characters of mycelia and conidia. Then, permanent slides were made for each fungi and storing in the Mycology Laboratory of Seed Pathology Centre, Bangladesh Agricultural University, Mymensingh, Bangladesh. Finally, it was confirmed that the the experimented brinjal seeds contained Phomopsis vexans, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger, Curvularia lunata, Penicillium spp.
Seed treatments Required amount of seeds were treated in the aqueous botanical extracts for 30 minutes. The concentration of the solution was 100% (v/v). For all twelve individual plant species were separately done. Then, to observe the comparison between botanical and chemical seed treating material, Vitavax 200 was used to treat the seeds for 30 minutes with recommended dose (25% of seed wt.), and in another plate seeds are dipped in distilled water for 30 minutes as control treatment.
Testing potentiality After treating, seeds were placed in sterilized Petri dishes and four layers of blotting paper were soaked into distilled water and placed into the Petri dishes. Each dish containing 25 seeds and 3 dishes were selected as replicates for each extract. Then, the Petri dishes were kept in the incubation chamber at 22 ± 2 ºC at light cycle 12/12 hours and data were recorded after 7, 10, 14 days after sowing (DAS). The total seed germination and percent seed infection are counted manually. But, the seeds were infected by specific fungi that identified and counted by observing the Petri dishes under Stereo Binocular Microscope and compared with the catalogue of Seed Mycology.
Experimental design and statistical analyses The experiment was done using Compleltly Randomized Design with four replications and treatments were designed as follows:- T1=Leaf extract of A. indica, T2=leaf extract of P. roxburghii, T3=leaf extract of S. persica, T4=leaf extract of C. procera, T5=seed extract of L. camara, T6=leaf extract of Clerodendron spp, T7=leaf extract of S. alata, T8=leaf extract of T. orientales, T9 =leaf extract of L. cylidrica, T10=leaf extract of M. oleifera, T11=leaf extract of C. spasriflorous, T12=seed extract of P. roxburghii, T13=leaf extract of T. dioicahae, T14=leaf extract of L. camara(leaf), T15=Vitavax 200 and T16=Control (no chemicals). Data were statistical analysed analysis of variance (ANOVA) and treatment means were compared using Duncan’s Muly=tiple Range Test (DMRT) at P=0.01.