PHENOLOGY OF WILD CASTOR, RICINUS COMMUNIS L. AND ITS PALATABILITY FOR ERI SILKWORM, SAMIA RICINI (DONOVAN)
S.N. GOGOI *
REGIONAL SERICULTURAL RESEARCH STATION, 4 JORHAT- 785 005, INDIA.
Y. DEBARAJ *
REGIONAL SERICULTURAL RESEARCH STATION, 4 JORHAT- 785 005, INDIA.
M.C. SARMAH *
CENTRAL MUGA ERI RESEARCH AND TRAINING INSTITUTE, JORHAT- 785 700, INDIA
B.B. BINDROO *
CENTRAL SERICULTURAL RESEARCH AND TRAINING INSTITUTE, BERHAMPORE-742 101, INDIA
*Author to whom correspondence should be addressed.
Abstract
Castor, Ricinus communis L. is the main food plant of eri silkworm, Sarnia ricini (Donovan). The present investigation in wild castor revealed differences in phenological events like germination, vegetative growth , formation of spike and capsules, defoliation of leaves and plant death at plains and hills in northeastern region of India. Maximum castor fruits mature from May (16.1%) to July (32%) at plains and from September (24.6%) to October (12.2%) at hills. Palatability of an eri silkworm was tested on wild population and revealed effective rate of rearing (ERR) 76.43% and 79.52% in plains and hills, respectively.
Keywords: Phenology, wild castor, field gene bank, plains, foot hills, palatability