Download (26Mb) - OAR@ICRISAT

adventitious slioot buds. Tliese seemed more applicable to gcnetic transformation
experiments where negation of thc aprcal dominance of axillary bud and shoot t ~p was the
salient feature of this explant. Removal of axillary bud followed by regeneration of
multiple shoot buds ga\e bctter adventitlous regcneratlon and multiple wounding sites.
Multiple shoot induction was found to bc betrur on liled~uin containirlg TDZ, when
compared ro the medium contaiiiing BAP. However, it \+as observed that prolonged
cul~c~rc uf llic cl~l;inls o~i 'l'D%-co~l~:~~~iiiig liicd~~~~ii ~ieg:~livcly i~it~rfcrcd wit11 I11rtI1cr
elongation. Ilc~ice, [lie inclus~on of TDZ was restricted to gerriiination and first pliasc of
induction. Sevcl.al other factors played an iniportant role 111 shoot bud induction. For
example, acidic pH sliowed efficient ~~iductiuii of niultiple shoots. Age of the seedling
was optimzed for all axillary meristeni explants wliere AM4 preparation required 5 to 6
days for the rcn~oval of axillary bud and another week for removal of multiplc shoot
buds. Inclus~on of cotyledo~i with AM4 explant was found to enhance multiple shoot
regeneration frequency. Two step elo~igation us~ng shoot elongat1011 medium (SEMI; MS
with 5 pM 2-iP and 2 1M klnct~n) in the first step followcd by 2 to 3 passages of sub-
cultures on SEM2 (MS wit11 2 pbl GA,) resulted a better elongation frequency. A novel
rooting sysrem was developed by employing filter paper br~dge tccli~iique aid tile liquid
root inductloll mediuni (RIM) consisted of MS will1 5 pM IDA. This ~rietliod resulted in
high rooring as ~vsll as transplantation frequelic~es. .All clficient liardeniiig nild
transplaiiration method was standardized by optimizing variables such as potting
medium, temperature, humidity, irrigation and phoroperiod. ~onviron~" growth chamber
was found to be better Fac~lity for Iiardening arid i~i~tial phase of tnnspla~itation while pod
maturation and harvesting was done in specially designed P2 facility. Best hardening of