Differential Count of Haemocyte from the Haemolymph of Muga Silkworm (Antheraea assamensis H.) reared on the host plant

Five types of circulating haemocytes have been identified from the haemolymph of 5th instar larvae of the Muga Silkworm (Antheraea assamensis) reared on Som leaves (Machilus bombycina) at Govt. Basic Muga Seed Farm, Khanapara, Assam, India. Haemocytes were identified by means of light microscopy as prohaemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids. Differential count of haemocyte from the haemolymph of fifth-instar larvae of Muga Silkworm were also studied and calculated. Among them, prohaemocytes were found to be the most abundant cell types in the haemolymph, whereas spherulocytes the rarest.

Association of Climatic Factors on Population Dynamics of Leaf Roller,Diaphania pulverulentalisHampson (Lepidoptera: Pyralidae) in Mulberry Plantations of Sericulture Seed Farm

The production of quality mulberry leaf and subsequent production of quality silk is hampered due to the incidence of various insect pests. The present study analyses the population dynamics ofDiaphania pulverulentalis(leaf roller), a serious pest of mulberry in a sericulture seed farm. The results indicated that maximum population buildup of the pest was recorded during rainy season. High humidity coinciding with low temperature because of southwest and northeast monsoon was conducive for breeding and multiplication of the pest. Correlation studies revealed that there was a significant negative correlation between increase in temperature and pest infestation. All other weather factors recorded from the study location have a positive correlation with incidence of the pest. The regression model developed also supported the relationship between the pest population buildup and weather factors.