Varietal screening of fennel against chalcid wasp, Systole albipennis Walker
Nema Ram and Ashok Sharma
Seven fennel varieties were screened for their relative susceptibly against S. albipennis. The results of two years data (Rabi 2011-12 and 2012-13) indicated that none of the fennel varieties was found completely free from chalcid wasp infestation. The categorization of varieties indicated RF-145 as least susceptible (damage <13.58%), whereas, RF-125, RF-143, RF-178, RF-205 and local cultivar grouped as moderately susceptible (damage 13.58 to 16.92%) and the variety RF-101 as highly susceptible (damage >16.92). The morphological characters and oil content of different fennel varieties were observed to find out their relationship with chalcid wasp damage. The time taken for 50 per cent flowering was positively correlated, while plant height was negatively correlated with chalcid wasp damage. The maximum chalcid wasp damage was recorded in variety with yellow colour flowers and least damage in light yellow coloured flowers variety. The seeds per umbel were negatively correlated with chalcid wasp damage. The oil content in different fennel varieties had significant negatively correlation with damage.