STUDIES ON THE GROWTH PARAMETERS OF ERI SILKWORM, Samia cynthia ricini (BOISDUVAL) AND ITS HOST EXPLOITATION FOR ENHANCED SILK PRODUCTION
Loading...
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY
Abstract
Studies on the growth parameters of eri silkworm Samia cynthia ricini (Boisduval)
and its host exploitation for enhanced silk production was conducted during Kharif
2019 to Rabi 2020 at the Department of Entomology, College of Agriculture, PJTSAU,
Rajendranagar, to evaluate castor genotypes suitable for rearing eri silkworm and its
subsequent performance.
Six different castor genotypes viz., PCS-262, PCH-111, DCS-107, ICH-66, 48-1
and DCH-519 when evaluated for their suitability for eri silkworm rearing, significantly
lowest larval duration ranging from 19.0 to 19.3 days was recorded when the larvae
were fed with PCS-262, DCS-107, PCH-111 and ICH-66. However, highest duration of
24.3 days was recorded on DCH-519. Similarly, larvae recorded maximum larval
weight of 5.43 g when fed with PCS-262 followed by PCH-111 (4.70 g) and ICH-66
(3.57 g). Other genotypes, resulted in larval weight of 48-1 (4.21 g), DCS-107 (4.33 g)
and DCH-519 (3.71 g).
With regard to cocoon weight, shell weight, shell ratio %, were also superior in
the batches of silkworms fed on the leaves of PCS-262 genotype (3.07g/cocoon, 0.398
g/ shell, 12.99 %) respectively. In terms of pupal weight highest of 2.68 g and lowest
of 2.16 g was recorded in PCS-262 and DCH-519 respectively when fecundity was
observed, it was maximum 335.7 when larvae were fed with ICH-66 followed by 332.5
on PCS-262. Similarly hatchability per cent ranging from 99.01 to 99.84 per cent was
recorded on DCS-107, DCH-519, 48-1, ICH-66, PCH-111, PCS-262.
The foliar constituents in the leaves of castor genotypes significantly varied
between tender and matured leaves. PCS-262 was found to be superior in elemental
composition viz., nitrogen, potassium of 5.217 per cent, 4.128 per cent in tender leaves
and 3.348 per cent and 2.895 per cent respectively in matured leaves. Phosphorous
content was highest in tender leaves of PCS-262 (1.86%) and PCH-111 recorded
highest phosphorous content of 1.52 per cent in matured leaves.While secondary
metabolites like tannins were lowest in 48-1 and PCS-262 genotypes. Highest phenol
content was recorded in matured leaves compared to tender and medium leaves among
castor genotypes representing their antioxidant nature.
Biochemical constituents showed influence on growth parameters and rearing
performance as protein being a major source for eri silkworm to synthesize the silk
consisting of two proteins namely fibroin and sericin were found to be highest in PCS 262 (32.59 %, 25.67 %) in tender and matured leaves. On the other hand, DCH-519
recorded lowest biochemical constituents such as moisture content (58.74 %), protein
content (23.84 %, 15.06 %), carbohydrate content (6.81, 6.61 mg/g) in tender and
medium and matured leaves respectively which in turn influenced growth parameters
such as highest larval duration (24.3 days), least cocoon weight (2.42 g), shell weight
(0.245 g) and lower pupal weight (2.16 g).
Description
Keywords
Citation
D10,632