Development of transgenic tomato resistant to early blight & Chilli for anthracnose (Ongoing)

Objective: 
  1. To improve the regeneration and transformation system in chilli cv G-4
  2. Generation of putative transformants in tomato cv Arka Vikas, Chilli cv G-4 through Agrobacterium mediated transformation with chitinase gene
  3. Molecular analysis of transformants
  4. Contained establishment and screening the transformants for disease resistance
PI: 

Dr J.B. MYTHILI

CO PI: 

Dr M. Manamohan

Dr Girija Ganeshan

Dr P. Chowdappa

Dr A. Sadashiva

Dr K. Madhavi Reddy

Achievements: 
  • Four genes viz., chitinase gene from bio-control gent viz., Trichoderma harzianum and Metarhizium anisopliae, polygalacturonase inhibitor protein (PGIP) a hydrolytic enzyme involved in fungal inhibition from chilli and NPRI a key gene involved in regulation of plant disease resistance have been cloned. All these genes have been put under expression cassettes under the control of CaMV 35S promoter and mobilized into binary vector for expression in plants for enhanced fungal resistance.

 

  • The advanced stabilized transgenic line with Trichoderma harzianum chitinase gene in T3 generation expressed 60% tolerance to Alternaria solani at the seedling stage in response to control plants while for two consecutive (T3 and T4) generations at fully grown stage, the transgenic plants recorded intermediate response with PDI of less than 50% while the control Arka Vikas recorded greater than 60% PDI.  Transgenic lines  also showed significantly reduced  lesion size compared to control  in the in vitro leaf bio-assy. The delayed development of disease ( about 10days)  and reduced disease development can help in effective disease management and thereby reduce yield losses of the crop  and reduced use of chemical pesticides can be expected.

 

  • With the objective of obtaining resistance against Alternaria solani  co-transforamation approach  using  Chitinase and PGIP genes in two Agrobacterium cultures was standardized  and co-transformants  with both chitinase and PGIP genes were obtained. This results suggest that this approach can be used for pyramiding tomato with  two or more genes for enhanced fungal resistance.

 

  • Problems  associated  with the low rate of conversion of shoot buds to elongated shoots as well as inhibition of rooting during optimization of  regeneration protocol for chilli were addressed.
X