Indian Scientists have warned that a Jamun berries and seed-eater wasp, scientifically known as ‘A. kerrichi’ is fast spreading its wings, threatening to inflict losses on Jamun tree growers.
Commonly found, evergreen Jamun is an economically important tree in India, which also has medicinal properties. Its berries and seeds are much sought after for their antioxidant, anti-inflammatory, anti-microbial and free-radical-scavenging properties.
However, the tiny but a potential pest of Jamun, A kerrichi, an eulohid seed borer which was reported from the agricultural fields in Pune way back in 1957, has been recently found seriously damaging the berries in Jamun trees (S Cumini) in fields in Karnataka's rural Bangaluru too.
The result of the study conducted by the scientists from ICAR-Indian Institute of Horticultural Research, country's leading institute in Bangaluru is published in the latest journal of the Current Science.
The scientists have called for spraying botanical pesticides as heavy infestation of jamun fruits by the wasp renders the berries unmarketable and hence loss to the farmers
The authors of the study noted that A kerrichi was initially reported from Pune, Maharashtra in 1957. "Besides this, no reports that highlight the economic importance and nature of damage of this eulophid seed borer in Jamun are available, possibly due to its limited distribution/occurrence and pestilence.
"However, in the recent past, several incidences of A kerrichi attacking S. cumini fruits causing extensive crop loss have been noticed in farmers' fields in rural Bengaluru," says the study that provides experimental details of the critical fruit stages that are susceptible to the pest for planning management interventions.
"In Jamun both whole fruit as well as seed are economically important. Considering the vast damage it can cause and the ability to build up in huge numbers (85 per fruit) in overlapping generations, A kerrichi can become a major problem to Jamun growers. Further, larval feeding affects seed viability and rate of germination. As the critical stage for infestation is G2, application of safe botanical pesticides at this stage may help reduce seed borer infestation," said the scientists.
They had randomly collected A kerrichi infested jamun fruits in different developmental stages from the infested trees. The collected fruits were separated into five groups, namely G1-G5 based on their size, colour and hardness. Observations on fruit diameter, length, mesocarp thickness and seed diameter from all the phenological stages (G1-G5) were made and recorded daily.
It was noted that heavy infestation of jamun fruits by A kerrichi had rendered the fruits unmarketable.
The scientists included P D Kamala Jayanthi, BR Jayanthi Mala and Anjana Subramoniam(Division of Entomology and Nematology) and A Rekha (Division of Fruit Crops) from the Bangaluru based institute.