SELECTION OF POTATO APICAL LEAF CURL VIRUS DISEASE-RESISTANT GENOTYPES, PEST SURVEILLANCE, SEED DEGENERATION, AND MANAGEMENT OF APHID IN FIELD CONDITIONS

Abstract

Objectives: Under All India Co-ordinated Research Project on Potato, studies on the selection of potato apical leaf curl virus disease-resistant genotypes, pest surveillance, seed degeneration, and management of aphid in field conditions were conducted at Hisar during 2017–2018. Methods: Sowing of seed tubers was done at recommended time and spacing in every experiment followed by spraying of required insecticides. Observations on different aspects were recorded and statistically analyzed to present results in tabular format. Results and Discussion: Out of 100 germplasm, seven were resistant and one was moderately resistant to potato apical leaf curl New Delhi virus, all the local genotypes were susceptible to disease. There was infestation of aphids, jassids, thrips, and whitefly irrespective of cultivars. Severe mosaic incidence ranged from 63.6 to 93.2%. The breeder seed was superior as it resulted in the highest seed tuber emergence (98.94%) and the least incidence of leafroll disease (0.80%) followed by seed tuber of seed plot technique (SPT). The conventional seed performed the poorest in terms of emergence and exhibited the highest disease incidence. Aphid appeared in the 47th meteorological week and it approached the ET level in the 52nd week. Whitefly population was the highest in the 47th week which continuously declined. Jassid population was very mild and thrips appeared in the 52nd week. Flonicamid 50 WG caused higher aphid mortality than imidacloprid after 24 h of spray. The maximum and minimum temperatures varied from 16.9 to 35.7 and 2.6 to 16.2° C, respectively. The morning and evening relative humidity was in the range of 82–100 and 24–75%, respectively. The wind speed ranged from 1.0 to 3.6 KMPH and the sun was shined from 0.3 to 7.6 h. The results of this study are close conformity of earlier researchers. Conclusion: It is concluded that resistant genotypes, breeder seed, and seed produced through SPT are promising in managing the disease successfully. Flonicamid is a good alternative of imidacloprid. Aphid is a major pest that plays a key role in transmitting viral disease of this crop, its population touched ET level in the 52nd week.