http://localhost:8080/handle/123456789/3266 Sat, 18 Apr 2026 14:22:27 GMT 2026-04-18T14:22:27Z http://localhost:8080/handle/123456789/3559 SCREENING OF SELECTED POTATO VARIETIES FOR VIRUSES (PLRV AND PVY) THROUGH GROWTH CHARACTERISTICS AND ELISA TEST ZEREEN, MST. ISRAT An experiment was conducted in glass house and laboratory of BADC to screen selected potato varieties viz. Asterix, Cardinal, Diamant, Lalpakri and Desiree against PLRV and PVY through growth characteristics and it was further confirmed through ELISA test. ELISA test followed by in vitro meristem culture performed in order to produce virusfree and sufficient amount of potato seed tubers. Among the selected potato varieties, the highest disease incidence of PVY and PLRV (1.22 and 1.89%) was recorded in Lalpakri and the lowest (0.33 and 0.44%) was in Asterix respectively. In Diamant, disease incidence of PLRV and PVY was 0.39% and 0.83% respectively. In Cardinal, disease incidence of PLRV and PVY was 1.56% and 1.11% respectively. In Desiree, disease incidence of PLRV and PVY was 0.44% and 1.22% respectively. Numbers of stems/hill of the virus free as well as infected cultivar were significantly different from each other. In both cases, Asterix showed the highest number of stems/hill followed by Cardinal, Desiree, Diament and Lalpakri. Numbers of nodes production of the virus free as well as infected cultivar were significantly different from each other. In both cases, Asterix showed the highest number of nodes production followed by Desiree, Cardinal, Diament and Lalpakri. The cultivars Asterix (12.12 tubers/plant) produced more tubers/plant followed by Desiree (10.43), Diamant (9.31), Cardinal (9.25) and Lalpakri (8.10). It was also observed that among the potato varieties tested against PLRV and PVY, Diamant produced 23.98 mm size tuber when infected with PLRV but PVY infection produced 21.43 mm size tuber. PVY infected Cardinal produced 22.88 mm size tuber but PLRV infection reduced size to 21.13 mm. Desiree produced 24.32 mm and 23.56 mm size tuber when infected with PVY and PLRV, respectively. Highest dry weight of whole plant was recorded in varieties Asterix (1.81 g) followed by Desiree (1.68 g), Diamant (1.66 g), Cardinal (1.63 g) and Lalpakri (1.55 g), respectively. Diamant produced 1.66 g dry weight/plant in PLRV and 1.52 g dry weight/plant in PVY infection. In PVY and PLRV infection Cardinal produced 1.60 g and 1.52 g dry weight/plant, respectively whereas Desiree produced 1.63 g dry weight/plant in PVY and 1.60 g dry weight/plant in PLRV infection. Asterix gave the highest percentage (92.7%) of survivability of plantlets followed by Lalpakri (90%), Desiree (87.5%), Cardinal (86.7%) and Diamant (71.7%). Asterix gave the highest percentage (99.70%) of virus free plantlets followed by Desiree (99.48%), Cardinal (99.47%), Diamant (99.10%) and Lalpakri (91.44%). From the results of this study it may be concluded that presence of viruses in potato plants hamper photosynthetic production and assimilation consequently all the growth characteristics which also depends on nature of viruses and potato varieties and Asterix are the most resistant to the both PVY and PLRV. A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka, In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE IN PLANT PATHOLOGY Wed, 01 Jan 2020 00:00:00 GMT http://localhost:8080/handle/123456789/3559 2020-01-01T00:00:00Z http://localhost:8080/handle/123456789/3558 SCREENING OF RESISTANT CULTIVARS OF BETELVINE (Piper betle L.) AGAINST FOOT AND ROOT ROT DISEASE CAUSED BY Sclerotium rolfsii HANIF, MOHAMMED ABU The causal organism of foot and root rot disease was isolated from diseased specimen with typical symptoms collected from affected betelvine. The isolate was pure cultured and identified as Sclerotium rolfsii The Sclerotium rolfsii was mass multiplied and the pathogenicity was confirmed by Koch’s Postulates. Eight betelvine cultivars viz. PB 001 (Chalitaguti) PB 002 (Chuadanga Pan), PB 003 PB (Moheskhali Pan), 004 (Laldingi Pan), PB 005 (Satkhira Pan), PB 006 (BARI Pan-1), PB 007 (BARI Pan-2) and PB 008 (BARI Pan-3), were explored in the screening experiment. Results were compiled based on physio-morphological features, days required for appearance of 1 st disease symptom, disease reactions, yield and yield contributing characters Betelvine cultivars were showed differential reactions against S. rolfsii causing foot and root rot disease. The vegetative growth parameters and morphological features of different cultivars of betelvine varied remarkably. The maximum vine increment per month (90.97 cm) was recorded in PB 003 and the lowest increment (46.87 cm) was in PB 006. The maximum length of internode (8.27 cm) was recorded in PB 004 and the minimum length (4.50 cm) was in PB 006. The maximum vine girth (1.63 cm) was recorded in PB 007 and the minimum girth (0.93 cm) was in PB 002. Significantly the highest length of leaf (22.07 cm) was recorded in PB 005 and the lowest (13.17 cm) was in PB 006. The leaf breadth (13.03 cm) was recorded the highest in PB 003 and the lowest (6.93 cm) in PB 006. The highest petiole length (8.63 cm) was recorded in PB 008 and the lowest length (4.03 cm) was in PB 002. The petiole breadth (1.13cm) was recorded the highest in PB 004 and the lowest (0.43 cm) in PB 008. The weight (g) of 100 petiole was recorded the highest in PB 004 (83.33 g) and the lowest weight (38.33 g) was in PB 006.The fresh weight of 100 leaves with petiole was recorded the highest in PB 004 (553.33 g) and the lowest weight (206.67 g) was in PB 006. The PB 006 produced significantly the highest number (23.00) of leaves per meter vine and the lowest number (13.67) of leaf was recorded in PB 003. The leaf number per plant per year was recorded the highest in PB 006 (414 leaves) and the lowest number was found in PB 003 (282 leaves). After inoculation, the time interval (days) required for appearance of 1 st disease symptoms among the betelvine cultivar differed significantly. The lowest incubation period (8 days) required for the cultivars PB 007 (BARI Pan-2) and PB 008 (BARI Pan-3). The highest incubation period (14 days) was required for PB 006 (BARI Pan-1). No symptom was appeared in the cultivars PB 004 (Laldingi pan). The disease incidence ranged from 0.00% - 100%. Among the betelvine cultivars, PB 004, (Laldingi pan) showed resistant (R) reaction while three cultivars viz. PB 006 (BARI Pan-1), PB-003 Moheskhali Pan) and PB 002 (Chuadanga) showed moderately resistant (MR) reaction. Two cultivars viz. PB 001 (Chalitaguti) and PB 005 (Satkhira) showed moderately susceptible (MS) reaction and the rest cultivars PB 007 (BARI Pan-2) and PB 002 (BARI Pan-3) showed highly susceptible reaction against S. rolfsii causing foot and root rot of betelvine. A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka, In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE IN PLANT PATHOLOGY Wed, 01 Jan 2020 00:00:00 GMT http://localhost:8080/handle/123456789/3558 2020-01-01T00:00:00Z http://localhost:8080/handle/123456789/3557 SURVEY ON THE MAJOR DISEASES OF WATERMELON IN TWO SELECTED DISTRICTS OF BANGLADESH Aftab, Rooksana A field survey was conducted to identify the major diseases of watermelon in the year of 2020 and 2021 at Subarnachar Upazila in Noakhali district and Dashmina Upazila in Patuakhali district. The laboratory works has done at Central Laboratory of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. Twenty villages from Ten Unions of Noakhali and Patuakhali districts were considered for survey and investigation of major diseases of watermelon. Altogether, sixty farmers were interviewed from Noakhali and Patuakhali district of Bangladesh. The incidence and severity of diseases of watermelon varied significantly among the locations. Depending on the disease incidence and severity, the major diseases of watermelon were leaf curl, leaf spot, foot and root rot. In leaf spot disease in both districts, the highest disease incidence and severity were 35.10% and 10.33% which were recorded in West Charbata at Noakhali district, respectively. In case of leaf curl disease of watermelon the highest disease incidence and severity were recorded in South Kocchopiya and Char Aminul Haq that were 74.53% and 18.33%, respectively. The highest powdery mildew disease incidence 11.33% and severity 4% was observed in South Kocchopiya in Noakhali. In case of foot and root rot disease, the highest disease incidence and severity was recorded in Auliapur at Patuakhali district which were 20.66% and 15% in West Charbata, Noakhali district, respectively. The highest disease incidence of leaf mosaic were recorded in South Kocchopiya at Noakhali district and Gochani at Patuakhali district which were 16.67% and disease severity were 2.33% at Char Mujib and South Kocchopiya in Noakhali while the lowest severity of leaf mosaic 1.33% was recorded in Gochani, Patuakhali district. In total, five diseases were recorded and identified in field conditions viz. Leaf spot caused by Alternaria alternata, leaf curl caused by chlorotic stunt virus, powdery mildew caused by Oidium sp, foot and root rot caused by Fusarium oxysporum and leaf Mosaic caused by virus. Considering the amount of severity of diseases, foot and root rot and leaf curl were major diseases occurred in watermelon fields in Noakhali and Patuakhali district, respectively. Moreover, in-vitro conditions fungi viz. Fusarium oxysporum, Aspergillus spp., Alternaria alternata, Rhizopus stolonifer and Chaetomium sp. were isolated and identified from the seeds of watermelon mixed varieties revealed by seed health test. The socio-economic status of watermelon farmer’s in Bangladesh revealed that the highest percent of farmers used 2 to 3 ha of land for watermelon cultivation and most of the money was used to prevent the watermelon from disease, insects and weeds which was about 28,000 Tk/ha. A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka, In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE IN PLANT PATHOLOGY Wed, 01 Jan 2020 00:00:00 GMT http://localhost:8080/handle/123456789/3557 2020-01-01T00:00:00Z http://localhost:8080/handle/123456789/3556 MANAGEMENT OF ANTHRACNOSE DISEASE OF CHILLI CAUSED BY (Colletotrichum capsici) THROUGH SELECTED TREATMENTS FOR SEED PRODUCTION MAHMUD, KAWSAR The in vivo experiment was conducted in the Central Farm of Sher-e-Bangla Agricultural University (SAU), Dhaka and in vitro experiment was conducted in the laboratory of the Department of Plant Pathology, SAU. The effect of eight treatments viz., Tilt 250 EC (Propiconazole), Ridomil gold 68 WG (Mancozeb+ Metalaxyl), Dithane M-45 (Dithiocarbarnate), Score 250 EC (Difenoconazole), Trichoderma harzianum (Bio-Control), Neem leaf extract (Azadirachta indica) Allamanda leaf extract (Allamanda cathartica) and a Control (T 0 ) were explored against Anthracnose of chilli (Colletotrichum capsici) during winter season 2019-2020. The efficacy of the treatments varied significantly in terms of disease incidence, disease severity and yield attributes of chilli. Among the treatments, Tilt 250 EC, Dithane M-45 showed promising performance against the disease. The lowest leaf incidence (4.31%) and leaf area diseased - LAD (4.16%) were recorded Tilt 250 EC. Similarly, the lowest fruit infection (3.93 %) and fruit area diseased - FAD (3.55%) were recorded in Tilt 250 EC (4.95%) and Dithane M45 (4.41%), respectively. Reduction of disease incidence and severity of anthracnose of chilli by spraying Tilt 250 EC also reflected in case of fruit yield, seed yield and subsequent seed health of harvested chilli seed. The highest fruit yield (10.23 t/ha) and 1000 seed weight (4.21 gm) were also recorded in case of application of Tilt 250 EC. The maximum seed germination of harvested chilli seed (87.5%) was also observed in Tilt 250 EC applied plots. Among the plant extract, neem leaf extract found to give good yield (8.04 t/ha) against anthracnose disease which was even better than Ridomil Gold 68 WG (7.9 t/ha) and Score 250 EC (7.67 t/ha). A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka, In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE IN PLANT PATHOLOGY Wed, 01 Jan 2020 00:00:00 GMT http://localhost:8080/handle/123456789/3556 2020-01-01T00:00:00Z