Department of Plant Pathology, College of Agriculture, Bijapur- 586 101, University of Agricultural Sciences, Dharwad, Karnataka, India. E mail: mm_jamadar@rediffmail.com
*Part of PhD thesis submitted by the senior author to the University of Agricultural Sciences, Dharwad, Karnataka.
Sensitivity of different grapevine anthracnose isolates to carbendazim in terms of their inhibition of spore germination determined by ‘hanging drop method’, indicated early germination of resistant isolates as compared to the sensitive isolates. Among the 25 isolates from different regions in Southern India; isolate Ea11 (Gulbarga) was found to be the most sensitive (99.3% inhibition) to carbendazim at MIC of 5.0mg/ml and was on par with isolates Ea25, Ea12, Ea9, Ea8, Ea19 and Ea17 at different concentrations evaluated. While Ea16 and Ea15 were found to be highly resistant even at higher MIC level of 100mg/ml, further it was revealed that the number of resistant isolates decreased as the concentration levels of carbendazim increased.
With respect to sensitivity to carbendazim by “Poisoned food technique”, considerable variability was detected among five representative isolates of anthracnose of grapevine. Among these, Ea11 was found to be significantly the most sensitive (100% inhibition) whereas Ea1 (Bijapur, local isolate) exhibited moderate reaction and Ea15 (Belgaum) was found to be significantly the most resistant (10.8% inhibition) isolate to carbendazim. Colletotrichum gloeosporioides isolates were found to be more sensitive to carbendazim than Sphaceloma ampelinum, which showed moderate resistance while Gloeosporium ampelophagum isolates exhibited variable reaction to carbendazim treatments.
Carbendazim sensitivity, anthracnose isolates, Sphaceloma ampelinum, Gloeosporium ampelophagum Colletotrichum gloeosporioides, grapevine
