2023 APSA Solanaciars Thank God It’s Friday - Session 4 8 December 2023 / 12:30 pm - 2:30 pm (GMT+7)


2023 APSA Solanaciars TGIF Session 4
8 December 2023; 12:30 – 14:30 hrs. (GMT+7)

Bacterial Wilt of Tomato: Challenges and Progress

12.30 – 12.35

Opening of the Webinar
Dr Seetharam Annadana, Chair of APSA R&D AG Member

12.35 – 12.40

New variety releases or endorsements

12.40 – 13.10

Root stock evaluation and field performance of grafted solanaceous vegetables
Dr. C. Narayanankutty
, Associate Dean, College of Agriculture, Kerala Agricultural University 

13.10 – 13.30

Discussion and Q&A Session

13.30 – 14.00

Bacterial Wilt: Confronting the Pathogen's Challenges
Dr. R. Ramesh
, Principal Scientist (Plant Pathology), ICAR – Central Coastal Agricultural Research Institute 

14.00 – 14.20

Discussion and Q&A Session

14.20 – 14.30

Closing remarks
Dr Seetharam Annadana
, Chair of APSA R&D AG Member

Speaker Bio & Abstract

Dr. C. Narayanankutty
Associate Dean, College of Agriculture
Kerala Agricultural University 

Dr .C. Narayanan Kutty joined Kerala Agricultural University in 1988 and served the University as Professor of Horticulture Assoc. Director of Research (Seeds) and Dean, College of Horticulture, Nodal Officer of the Centre for Hi-Tech Horticulture & Precision Farming, KAU, Velanikkara. Dr. Narayanan Kutty is associated with the development of ten vegetable varieties released by Kerala state variety release committee. The tomato varieties ‘Manu Lakshmi’ and ‘Manu Prabha’ developed by him are the first tomato varieties developed in the state having bacterial wilt resistance coupled with high fruit size. The snake gourd variety ‘Manu Sree’ has proven to be the highest yielding among the snake gourd varieties released so far in the state... Dr. Narayanan kutty was the first to identify tropical varieties of cool season vegetables suitable for cultivation in the state.. Dr. Narayanan kutty has standardised the technology for large scale production of vegetable transplants in soil less media under protected conditions. In order to tackle bacterial wilt, resistant root stocks were identified and the technology for grafting solanaceous vegetables like tomato, brinjal, chilli and capsicum on resistant root stocks was standardised. Dr. Narayanan Kutty has so far published more than 60 research papers in peer reviewed research journals, International and National Conferences besides a large number of popular articles, bulletins and other extension publications. In 2006 he was selected for the Israel Government Scholarship for undergoing advanced training in high tech vegetable production. He is the recipient of the Best Scientist Award of the Kerala Agricultural University 1n 2012 and Krishi Vigyan Award of the Govt. of Kerala in 2014. Dr. Narayanan Kutty has served as a Technical Consultant to CINI (Central India Initiative) of M/s Tata Trusts, Mumbai. He is a member of the State level committee on Hi tech Agriculture and a technical advisor to the Vegetable and Fruit Promotion Council of Kerala.  He is also a Fellow of the Indian Society of Vegetable Science, Varanasi.


Bacterial wilt caused by Ralstonia solanacearum is a devastating soil borne disease in the humid tropics especially in  solanaceous vegetables viz. tomato, brinjal, chillies, capsicum and also in cucurbits like bittergourd, ashgourd, snakegourd and cucumber. Cultivation of resistant varieties is one of the viable options to manage bacterial wilt. But most of the wilt resistant cultivars do not have the yield potential or fruit qualities of F1 hybrids that are widely preferred by the farmers for commercial cultivation. Grafting is a tool widely practised to tackle various biotic problems especially soil borne diseases in vegetables. Screening compatible rootstocks resistant to bacterial wilt is a prime requirement for undertaking grafting on a commercial scale. With this background an attempt was made to identify bacterial wilt resistant solanaceae genotypes for use as rootstocks and to study the field performance of the grafted plants. 16 genotypes which included eight Solanum species, three reportedly resistant local collections of Solanum melongena and two wilt resistant varieties, one each in brinjal and chilli were spot planted with Pusa Ruby, a universally susceptible check variety of tomato in a wilt sick plot for two consecutive seasons. Significant differences were observed for bacterial wilt incidence among the solanaceous species, local collections and varieties. High wilt incidence (PDI) ranging from 75 to 100 per cent was observed in seven out of eight Solanum species tested. Days to wilt did not differ significantly among the genotypes tested. The three local brinjal collections and the brinjal variety “Haritha”, along with chilli cultivar ‘Ujjwala’ showed resistance to bacterial wilt. During the second season all the above collections and varieties except Solanum torvum were found resistant to bacterial wilt. The check genotype Pusa Ruby recorded 100 per cent wilt incidence during both the seasons.

Confirmatory screening against bacterial wilt through artificial inoculation by root dipping, media drenching and stem injection was carried out in the resistant genotypes. Two local brinjal collections, Ujjwala, Haritha and S.torvum showed resistance to bacterial wilt. There was no significant difference among the three inoculation methods tried. 

Grafted and non- grafted plants of selected hybrids of capsicum and tomato were tested in the same wilt sick plot used for field evaluation studies. All the grafted plants of capsicum and tomato showed resistance to bacterial wilt. Yield per plant was also significantly high in grafted tomato genotypes. Grafted capsicum plants also showed the same trend with respect to wilt incidence and yield. Among the different rootstocks used, PDI was more in plants grafted on to Solanum torvum when compared to those grafted on the brinjal variety “Haritha”. 

Dr. R. Ramesh
Principal Scientist (Plant Pathology)
ICAR – Central Coastal Agricultural Research Institute

Dr. R. Ramesh is a Plant Pathologist in the Central Coastal Agricultural Research Institute of Indian Council of Agricultural Research (ICAR). He worked extensively on bacterial wilt disease of solanaceous vegetables, diversity and virulence of Ralstonia solanacearum and strategies for its management. Outcome of his research includes the release of bacterial wilt resistant varieties in eggplant and development of other promising wilt management technologies. His current areas of research include 1) understanding the pathogen virulence and host resistance in bacterial wilt system 2) development of biological solutions to the major soil borne diseases of coastal regions. 

Bacterial Wilt: Confronting the Pathogen's Challenges

Bacterial wilt disease poses a significant threat to tomato production in India and worldwide. This disease is primarily caused by the soil bacterium Ralstonia solanacearum, which can affect a wide range of plant species. The pathogenicity and virulence of R. solanacearum are attributed to the presence of multiple virulence factors and effector proteins. Despite efforts to manage bacterial wilt, its control has proven challenging due to the presence of diverse bacterial strains, the bacterium's ability to survive adverse conditions, a wide range of host plants including asymptomatic hosts, and an efficient mechanism for invading the host. In this presentation, I will provide a concise overview of bacterial wilt disease, discussing aspects such as pathogen diversity, virulence factors, and various management strategies. These strategies encompass the use of resistant plant varieties, grafting onto resistant rootstocks, the application of bio-fumigants, and plant-based products. I will also address the prevailing challenges associated with the management of bacterial wilt disease.