Efficacy of sea plant extract (Kappaphycus sp) in growth of mulberry and subsequently boosting the immunity against BmNPV in silkworm, Bombyx mori L

Field experiment was conducted to evaluate the performance of sea plant extract sprayed at different interval of time on mulberry and the treated leaves were fed to the silkworm Bombyx mori which were infected with BmNPV. It was found that foliar application of sea plant extract from LBS 13 at 1.5 ml/l at 45th day after pruning enhanced the leaf yield per plant by 308.81 g/pl, average plant height by 150.42 cm, number of shoots present (14.32) and leaves per plant (400 leaves per plant) when compared with control. When the treated leaves were fed to the BmNPV infected silkworms, LBS13 at 1.5 ml/l recorded highest larval weight of 3.33 g/larvae with larval duration of 7.67 days followed by least larval mortality (3.33%) and percent disease incidence (11.33%) when compared to control. The study evidenced that application of sea plant extract of Kappaphycus sp. has improved the growth attributes of mulberry, the only food for B mori and inturn had a direct positive impact on development of B. mori.