​Integrated Management Protocol for Bacterial Wilt Disease of Tomato in Ralstonia solanacearum Affected Soils in Kerala State

Background: Management of bacterial wilt of tomato in Ralstonia solanacearum affected soils is a major issue in tomato cultivation in different agro-ecological regions in Kerala state which affects the production and productivity of the crop. To develop a suitable management protocol for this disease, the field experiments were conducted during 2019 and 2020 in a bacterial wilt-sick field at Kerala agricultural university, Thrissur, Kerala, India. Methods: Twelve different treatments viz. soil application of bleaching powder, soil test based lime application, streptocycline root dip, drenching of copper hydroxide and copper oxychloride at different doses, seed treatment and seedling dip with Pseudomonas fluorescens, drenching of Pseudomonas fluorescens, planting grafted seedlings and different integrations and combinations of the above treatments were assessed for the management of bacterial wilt. Result: The majority of integrations were superior over individual treatments. The higher yield with less disease incidence was obtained from the integration of soil treatment of bleaching powder (15 kg/ha) + soil test based lime application + streptocycline (@ 2 g/10 L) root dip + drenching of copper oxychloride (@ 0.3%) and therefore, this integration protocol is recommended for management of bacterial wilt of tomato in wilt affected soils in Kerala state.

Air PDAM Basmi Corona

Mengapa air PDAM? Karena air PDAM berisi klor. Disinfeksinya menggunakan kaporit (kalsium hipoklorit, Ca(OCl)2) atau bleaching powder atau puyer kelantang atau chlorinated lime. Setelah diinjeksikan atau dibubuhkan ke dalam air di reservoir, kisaran waktu kontaknya (t, time) antara 15 - 30 menit. Dosis klor antara 0,2 - 40 mg/l. Keuntungannya, ada sisa klor antara 0,2 – 0,5 mg/l. Sisa klor ini dibutuhkan apabila di ruas pipa distribusi terjadi rekontaminasi bakteri yang masuk ke dalam pipa akibat kebocoran. Sisa klor inilah yang diharapkan mampu membasmi bakteri itu (Cahyana, 2004, hlm. 239 – 242)).

Integrated management of bacterial wilt and root knot nematode of brinjal

The field experiment was conducted at Regional Agricultural Research Station (RARS), Hathazari, Chattagram to find out the efficacy of integration of poultry refuse (PR) with stable bleaching powder (SBP) or CaNO3 and Furadan 5G for the management of bacterial wilt (Ralstoniasolanacearum) and root-knot nematode disease (Meloidogyne incognita) of brinjal. Soil was treated with PR @ 3 t/ha 3 weeks before transplanting, stable bleaching powder @ 20 kg/ha during final land preparation and Furadan 5G @ 20 kg/ha on the day of seedlings transplanting while CaNO3 was used as soil drenching 10 days after seedling transplanting. Results showed that integration of poultry refuse with Furadan 5G and stable bleaching powder or CaNO3 reduced root-knot and bacterial wilt diseases and increased plant growth as well as yield of brinjal. The most effective treatment combination was PR + stable bleaching powder + Furadan 5G with early sowing, followed by PR + CaNO3 + Furadan 5G with early sowing for the management of bacterial wilt and root knot nematode diseases and increasing plant growth and yield of brinjal. The technology, poultry refuse+ stable bleaching powder + Furadan 5G was validated at Bangladesh Agricultural Research Institute (BARI), Gazipur, Regional Agricultural Research Station of Jessore, Hathazari and Jamalpur and also at Agricultural Research Station and farmers field at Burirhat, Rangpur and OFRD farm at Alamnagar, Rangpur. The validation trials showed that integration of poultry refuse + stable bleaching powder+ Furadan 5G in early sowing was an effective management package of bacterial wilt and root knot nematode diseases of brinjal which also offered 21.81 to 25.98% higher yield over the conventional practices. Bangladesh J. Agril. Res. 44(3): 427-437, September 2019

Effect of Washing on Reducing Bacterial Loads in Common Vegetables Sold in Dhaka City

Vegetables and fruits can be contaminated with microorganisms from different sources during production and processing. Quality of vegetables usually relies on the quality of processing water and sanitizers used to reduce microbial load and increase shelf-life of vegetables. The present study demonstrates the role of washing on reducing bacterial loads in common vegetables sold in Dhaka city. A total of seventy two samples comprising of eighteen types of fresh vegetables were collected. Total heterotrophic bacteria, coliforms and Enterobacteriaceae were determined in 72 samples including potato, tomato, carrot, cucumber, green chilli, bean, eggplant, cauliflower, turnip, radish, capsicum, pumpkin, cabbage, gourd, papaya, bitter gourd, snake gourd and ridge gourd before and after washing with tap and filtered water, halotab water, bleaching powder (0.2%) solution and bleaching powder (0.2%) with citric acid (0.1%) for 10 minutes. Tap water, filtered water, bleaching powder (0.2%), halotab solution and bleaching powder (0.2%) + citric acid (0.1%) solutions were found to be effective and significantly reduced the bacterial loads in vegetables compared to the unwashed vegetables (P<0.01). Effect of washing vegetables using tap and filtered water were found to reduce load of total viable bacteria to 0.85-2.05 log10cfu/g and 2.38-3.36 log10cfu/g, respectively compared to those of unwashed samples. The efficiency of washing for reducing the bacterial load depends on the quality of washing water used and the types of disinfectant solutions used. An appropriate washing technique can significantly reduce the bio burden in contaminated vegetables and may reduce the risk of foodborne infections associated with the consumption of vegetables. Bangladesh J Microbiol, Volume 35 Number 2 December 2018, pp 96-101

Effect of some chemicals on incidence of poato soft rot disease in Bangladesh

Bactericidal effect was investigated by chemicals against potato soft rot bacteria in vitro and in storage. The chemicals were acetic acid, boric acid, bleaching powder, lactic acid, calcium hydroxide, calcium chloride, potassium chloride and sodium hypo-chloride. Among eight chemicals only three chemicals viz. acetic acid, boric acid and bleaching powder showed bactericidal activity against potato soft rot bacteria Pectobacterium carotovorum subsp. carotovorum (E. carotovora subsp. carotovora) P-138 in vitro. Based on the results of in vitro experiment three chemicals, acetic acid, boric acid and bleaching powder were used to control soft rot disease of potato in storage. Fresh potato tubers were dipped in 0.2% solution/suspensions of acetic acid, boric acid and bleaching powder for 30 min. Then soft rot bacteria Pectobacterium carotovorum subsp. carotovorum P-138 was inoculated on potato. Finally potatoes were stored for 22 weeks in net bags in sterilized condition. All the three chemicals significantly decreased the infection rate, loss in weight and increased percentage of disease reduction (PDR) of potato. Boric acid was the most effective in controlling the soft rot disease of potato in storage followed by acetic acid and bleaching powder. So these chemicals may be used for seed purpose storage of potato tubers for year round storage at farmer’s level.Bangladesh J. Sci. Ind. Res. 52(2), 135-140, 2017

A review on bacterial stalk rot disease of maize caused by Dickeya zeae

Bacterial stalk rot of maize caused by Dickeya zeae previously known as E. chrysanthemi pv. zeaehave economic importance of reduced crop yield up to 98.8%. The disease is more prevalent in rainy season in India. The bacterium prefers high temperature and moisture for their growth result is plant toppled down within week. The pathogen has wide host range (maize, rice, tomato, chilli and brinjal etc.) which help to pathogen for long survival in soil. The bacterium characterized by biochemical and molecular tactics. In present, Pel gene and rDNA specific primers are frequently used for D. zeae characterization. The pathogen significantly controls under in vitro and in vivo condition via bleaching powder (drenching of 100 ppm) and antibiotics. The present studies generated data on pathogen nomenclature, etiology, epidemiology, host range, pathogen survival, biochemical, physiological and molecular characterization, germplasm evaluation and disease management.