Volume 5 Issue 3 (In Progress)
[Uncorrected Proof: Final version will be published soon]
 First report of jackfruit decline caused by Phytophthora spp. in Bangladesh
Farhana Jenny1, Md Abdul Kader2, Md Abdullahil Baki Bhuiyan2
doi: 10.5455/faa.2194 pp: xxx – xxx
A survey was conducted at Gazipur, one of the major jackfruit producing districts in Bangladesh where decline syndromes were frequently observed. The characteristic symptoms of jackfruit decline included trunk canker, wilting, dieback of the canopy and in some cases complete death. The disease incidence was increased with the increase of plants age. Among the isolated fungi from the study area, only Phytophthora spp. were found to be pathogenic and caused decline symptoms in artificially inoculated jackfruit seedlings. Based on the morphological data, the isolates were confirmed as Phytophthora spp. To the best of our knowledge, this is the first report in Bangladesh.
Keywords: Dieback, wilting, canker, sporangium
 Impacts of nitrogen on plant disease severity and plant defense mechanism
Department of Plant Pathology, Faculty of Agriculture, Agriculture and Forestry University, Rampur, Chitwan, NEPAL
doi: 10.5455/faa.103334 pp: xxx – xxx
Nitrogen(N) is considered the most important factor to help the growth and development of plants. This is the building block for plant protoplasm and the chlorophyll molecule component for the photosynthesis process as well. Although it is apparent that the availability of N affects disease, the underlying mechanisms remain unknown. Many data indicate that the greater use of N fertilizers affected crop disease incidence. In comparison, cases are also recorded in which a decrease in N fertilization increases the severity of the disease, suggesting a complex relationship between them. N plays a significant role in regulating signaling networks that are active in reacting to a broad variety of biotic and abiotic stresses. In terms of physical, biochemical, and molecular mechanisms, the relationship between N and plant defense is considered. N has negative effects on physical defenses and the development of anti-microbial phytoalexins, but positive effects on defense-related enzymes and proteins that influence both local defense and systemic resistance. These all factors are implicated in plant defense signaling pathways but their role in plant defense is less well studied. This review aims to explain current knowledge of pathways connecting plant N status with the plant disease severity and plant defense. While this analysis highlights the crucial role of N nutrition in plant defense, further research is desperately required to provide a thorough overview of how interacting networks affect competing virulence and defense mechanisms.
Keywords: Nitrogen, Disease severity, Plant defense, Physical defense, Biochemical defense, Molecular defense
 Farmers’ knowledge and perceptions of virus diseases affecting hot pepper (Capsicum sp.) and their management in Rwanda
Bancy Waithira Waweru1, Dora Chao Kilalo1, John Wangai Kimenju1, Placide Rukundo2, Douglas Watuku Miano1
1Department of Plant Science and Crop Protection, College of Agriculture and Veterinary Sciences, University of Nairobi, P.O. Box 29053-0625 Kangemi, Nairobi, KENYA
2Rwanda Agriculture and Animal Resources Development Board, P.O. Box 5016, Kigali, RWANDA
doi: 10.5455/faa.113641 pp: xxx – xxx
Hot pepper (Capsicum spp.) is an important cash crop in Rwanda however, its productivity can only increase after addressing factors that limit its production. This study aimed at revealing the farmers’ knowledge and perceptions of virus diseases and their management in Rwanda. A survey was conducted between February and March 2018 in the main hot pepper growing areas covering low, mid and high-altitude agro-ecological zones (AEZs). Household data were collected using a structured questionnaire from 101 respondents and analysed using descriptive statistics. Majority of farmers (86.1%) indicated that pests and diseases were the main constraints to hot pepper production. Viral diseases were perceived by 71.9% of the farmers as the most serious diseases while 51.4% and 12.9% of them reported that aphids and whiteflies were the major insect pests of hot pepper, respectively. Only 17.8% and 25.7% of the farmers attributed the cause of the viral diseases to insect vectors and the use of infected seeds, respectively. The main method used to control viral diseases was application of synthetic pesticides. About two-thirds of the farmers lacked in knowledge of viral disease symptoms, spread and management across all AEZs. Majority of the farmers (80.2%) did not have access to extension service or training but relied mainly on farmer-interactions for information. Farmers awareness of viral diseases was significantly influenced by training (χ2 = 29.205; P = <0.001) and age (χ2 = 10.421; P = 0.005). Therefore, interventions such as farm-level training to raise the farmers’ awareness of diseases, especially viral diseases and integrated disease management are needed. This study provides baseline information for the development of sustainable integrated pest management (IPM) strategy for hot pepper viral diseases in Rwanda.
Keywords: Capsicum spp., constraints, virus diseases, farmers’ perception, pest management
 Water quality, bacterial load and hematological investigations of three over-wintering catfishes in Mymensingh District of Bangladesh
Mahabuba Shirin1, Tamanna Tabassum1, Drubo Mustofa Evan1, Kamrun Naher Azad1, Mousumi Akter2, Tanvir Rahman1
1Department of Aquaculture, Bangladesh Agricultural University, Mymensingh-2202, BANGLADESH
2Department of Agricultural Chemistry, Bangladesh Agricultural University, Mymensingh-2202, BANGLADESH
doi: 10.5455/faa.86150 pp: xxx – xxx
Studies were conducted to determine the water quality parameters, bacterial load in water and hematology of Pangasianodon hypophthalmus, Heteropneoustes fossilis and Ompok pabda reared in 15 over-wintering catfish ponds located at different upazila under Mymensingh district. Participatory rural appraisal (PRA) technique tools such as personal interview, focus group discussion (FGD) and key informant interview with fish farmers were done to collect preliminary data. Fish and water samples were collected from catfish ponds and were analyzed in the Fish Disease Laboratory, Faculty of Fisheries, Bangladesh Agricultural University, Mymensingh, Bangladesh. The microbial loads of pond water (CFU/ mL) were determined by ten-fold serial dilution using Tryptone Soya Agar (TSA) after incubation at 25 °C for 48 h. Hematological analysis of blood samples were done to determine RBC, WBC, hemoglobin, blood glucose level and Mean Corpuscular Hemoglobin (MCH) of the over-wintered catfish. It was found that the water temperature, pH, dissolve oxygen, total alkalinity and ammonia ranged from 27 to 20.5°C, 8.2 to 7.0, 7 to 5 ppm, 190 to 120 ppm, 0.03 ppm, respectively during the study period. Among the 15 ponds, the highest and lowest temperature was recorded in P. hypophthalmus ponds. The highest alkalinity was observed in P. hypophthalmus ponds and minimum was found in O. pabda ponds. The ammonia concentration was more or less similar (0.03 ppm) in 15 ponds. Average bacterial load of rearing water was ranged from the highest 2.6 ± 1.60 ×105 CFU/ mL to lowest 2.3 ± 1.93 ×103 CFU/ mL in H. fossilis ponds. The study revealed maximum RBC, WBC contents and the highest glucose level in O. pabda and minimum in H. fossilis and P. hypophthalmus. However, MCH and hemoglobin levels were found higher in P. hypophthalmus and lower in O. pabda. The study revealed preliminary data regarding over-wintering farm condition, bacterial loads of over-winter water, hematology and water quality parameters of three over-wintering catfish which also indicated the unplanned management of over-wintering ponds that sometimes affects water quality and hematology of catfish. The findings may contribute for the proper health management of fish reared under over-wintering condition.
Keywords: Water quality, bacterial load, hematology, over-wintering, catfish