BIVOLTINE RACE AND

.- Freserve coeoonslpupae at optimurn ternperature (25'C) and hunridity (7&%j"
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Conduet pupal gut examination immediatetry after the arrival of seed eoeCIons for the
incidence eif Pebrine.
Subject a sarnple of cococns froln eaeh lot to high temperature of 35"C for early eeloson
and to facilitate eartry detection of pebrine. Test ti-re emerged moths for pebrine disease
to eliminate risk and wastage of l*hslur'
Cut open at one end of the coer'ron to remove the pupa for determining the sex"
Normatrly sexing is done rnanually by visual examination of their sexual markings.
Cut and separat,e the eoeoons at least three days before emerge$ce" nt is especially
irnportant for raees sherwing above ZAVo e*co*n siretrl ratic]"
Preserve the seed pupae ilr trays in single laver om eorrugarad paper or powclered paddv
husk (Fig.16).
Cgver the pupae rvith perforated news paper $ne day prior to emergenee to facilitate
the emerged ryrcths eolrie on the paper and eoll*ction cf in*tFrs becorne easy. Besides,
this helps in absorption *f urine, while pieking.
1S.1. Mc€fu emergenee
- fu{ot}rs emerge t2-L3 enays {roclrn temperature 24-25'{} from the day of spinning.
Emergenee starts early in pciyvoitines {1S-11 days} than bivoltines t12-13 days)"
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trn e ase af Pure Mys*r*, sinee the coeoon'sheli Iayer is soft, sex seflaration is litttre difficult
(beeaus* pupa ffia'f b* *iamaged whiie cutting ttre eocoon shell). But as the rnatre and
fernale rir*ths *r$erg* at tw'o disiinet peaks they are con:fortably eclleeteel sellarately"
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Symeha"elmi s a€$$ra sf xs?s$fu ersa*rgex? ee
Planning for synctrrrcidsatiCIn should start at the bmshing time of parental breeds.
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trf the cocooils are meant fcr hy-brid preparation, tteen the total incubation, rearing period
and ernergence of moths are to b'e caleulated and a*cordingly the durnbbeli lines are
bnrshed two days earlier than oval lines, sc ttrat maie and femaie rnoths are readily
available for hybridisaticn. Sometimes ttrere ma_v be difference in the spinning Erf the
two bresds due t* the rearing conditions " {n such easss, the ernergenqe clf moths in the
twqr trreeqis can be adjusted by selecting cocoons of matei:ing spinning date.
* If the symehr*nisation is to be done at perpal stage, the pupae shouid be refrigerated,
preferably tr day' prior to emergence, for fcur tc six days (maximurn) at 5 to 1S'C"
1S"3. Coupling
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Keep ccupl*d moths uneXisturbeel for 3-4 hours in iltrumainated and well ventilated place.
Maintain temperature anetr hurnidiry at 23-25"C an& 7&^75% respectively.
Gently tap the decoupled fernale moths to induce urinaticn.
* Cold store the maie moths irnrnediately after separation at 5"C upto 3-4 ctrays .
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