STAGE SPECIFIC FOOD CONSUMPTION AND UTILIZATION BYTHE MEXICAN BEETLE, ZYGOGRAMMA BICOLORATA PALLISTER(COLEOPTERA: CHYSOMELIDAE) ON PARTHENIUMHYSTEROPHORUS LINNAEUSAmrit Mohapatra, Satya Narayan Satapathy, Dibyajyoti Swain, Soumya Sree Panda,Rupali Shrivasini Parida, Priyanka Priyadarshini and Subhashree Subhasmita PaikarayAbstract The food is the foremost need for the existence of all living organisms and the fluctuations in its availabilitystrongly affects the population dynamics of both the primary and secondary consumers. In the presentstudy we have investigated the effect of food (Parthenium weed) resource fluctuations, in terms of quality,on the feeding attributes of the Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae).Quantitative food utilization indices were measured in different larval instars and physiological ages ofadult Zygogramma bicolorata Pallister. Among the larval and adult stages of the beetle, third instar larvaeand egg laying females ingested maximum food. Various growth parameters like relative consumptionrate (RCR), relative growth rate (RGR) and approximate digestibility (AD) were relatively higher in thefirst, third and fourth instar and egg laying females. Efficiency of conversion of ingested food (ECI) andefficiency of conversion of digested food (ECD) were maximum in first, third and fourth instar larvae anddecreasing trend was observed in second instar larvae. During pre-oviposition stage adult, these parametersincreased tremendously in contrast to senescent stage. However, the fourth instars had higher feedingattributes than the adult females, proving them to be the better bio-control agents of Parthenium weed thanthe adult females. However, field based studies are still needed to validate the present findings. |