PROCEEDINGS OF ROUND TABLE CONFERENCE ON LITCHI BORERS HELD AT NRC LITCHI ON DECEMBER 4, 2015

 

Fruit borers (Conopomorpha  spp.) are major pests of litchi and have been reported to cause

40-80% yield  loss.  Presently insecticides are being relied heavily for management of litchi fruit borer. In the absence of clear residue analysis data for most of the insecticides being used by farmers, it is highly undesirable to continue the practice of chemical pest management. Hence it was felt that there is an urgent need to take stock of the situation of litchi borers in general and fruit borer in particular and identify research gaps which could form basis to develop safe and effective management strategies. With this background, the CRP on borers, entrusted with the mandate of devising sustainable borer management practices and ICAR- NRC Litchi, Muzaffarpur, the nodal institute for litchi research in the country have organized a one day   ‘Round Table Conference on Litchi borers’ at ICAR-National Research Centre on Litchi (NRCL), Muzaffarpur, Bihar on December 4th, 2015.

 

                    The meeting was attended by scientists, including entomologists and horticulturists, from NRC Litchi - Muzaffarpur, IIHR - Bengaluru, CHES - Bhubaneswar and State Agricultural Universities who are part of AICRP on Fruits. Dr. A. Krishnamoorthy, Principal Scientist (Retd.), IIHR and Ex-PI, CRP on Borers was the external expert. Dr. Vishalnath, Director, NRC Litchi chaired the sessions. At the outset, delegates were welcomed by Dr. Pandey, Chairman, PME, NRC Litchi. The session started with Dr. P. V. Rami Reddy, Principal Scientist and PI, CRP on Borers, ICAR-IIHR, Bengaluru introducing the topic and presenting an outline of CRP on Borers and the essence of the Round Table Conference. Dr. Reddy highlighted that the Horticulture Science Division of ICAR headed by Hon’ble DDG (Hort. Sci.), Dr. N. K. Krishna Kumar has been giving special attention to CRP on Borers and emphasizing the relevance of taking into account the ecology of the pests while formulating management practices. Since systematic studies on litchi pests in the country are still at nascent stage, NRCL should take lead in  generating the information on species complex, distribution, bioecology, natural enemy complex of litchi fruit borers.  Dr. A. Krishnamoorthy, Ex-PI, CRP Borers elaborated on the importance of this type of small  but focused group meetings involving only the concerned researchers. He mentioned that already four such Round Table Conferences were organized under CRP on Borers on topics like semiochemicals, Conogethes, Coffee white stem borer and cashew borers.  Since developing geo-maps is one of the major objectives of CRP on Borers, involving AICRP centres in documentation is very important.

 

In the presidential remarks, Dr. Vishalnath, Director, NRC Litchi appreciated the efforts of CRP on Borers in taking initiative to organize an exclusive meeting on litchi borers. Dr. Vishalnath expressed concern that, in litchi, tackling borer problem is a priority area and concerted efforts are need of the hour. He assured that NRCL would be in forefront to implement the suggested technical programme and coordinate the centres working on litchi borers. Dr. Vishalnath also suggested to explore both short and long term strategies for borer management.

The technical session started with Dr. Kuldeep Srivastava, senior scientist (Entomology), NRCL making a presentation on the overall view of litchi borers including diversity, population dynamics, management etc. Dr. Srivastava mentioned that three species of borers viz.,

C. sinensis, C. cramerella and C. litchiensis occur in India. However the correct species identity remains an unresolved issue. Till some time back C. cramerella was considered to be the dominant species. However the subsequent molecular identification of specimen revealed that the species was C. sinensis. Another interesting aspect came out in the presentation was that the incidence of borer had increased with increased rainfall during April-May months. After the presentation the following points were deliberated.

 

Dr. H. S. Singh, Principal Scientist and Head, CHES, Bhubaneswar outlined the borer status in Odisha. Dr. Singh underlined the scope of EPN against pupal stage. The poor collection of moths in pheromone traps designed by PCI, Bengaluru could be attributed to the wrong identification of species, as they are primarily meant for C. crameraella. Hence it is advisable that the chemistry identified for C. sinensis  elsewhere and published can be synthesized and evaluated.  He also mentioned that fogging and spraying inert clay material might help to control borer.

 

Dr. P. D. Kamala Jayanthi, Principal Scientist and National Fellow, IIHR made a presentation on the ‘Scope of semiochemicals in litchi fruit borer management’. She emphasized the importance of correct species identification for achieving success in pheromone studies as even population differences could impact pheromone performance. She mentioned that the basic components of pheromones identified for C. cramerella and C. sinensis are same but their proportions differ. From the fruit samples collected from Chettalli in Karnataka, Dr. Jayanthi found the incidence of Deudorix epijarbas adding another dimension to the species complex of litchi fruit borers.

Dr. Jayanthi stressed that understanding the insect behavior and identifying alternate hosts is crucial to devise pheromone and kairomone based interventions.

Dr. J. C. Prabhakar from RAU, Sabour expressed that incorporating incompatible Wolbachia could be explored. The meeting was followed by  a visit to experimental plots and laboratories of NRC litchi.

                 

                The following were the action points drawn based on the deliberations.