A Survey of Microspore Embryogenesis in Leaf Mustard (Brassica Juncea)

Doubled Haploids: A Powerful Biotechnological Tool for Genetic Enhancement in Oilseed Brassicas

“…Replacement of culture media after microspore isolation helps in reducing the autotoxins thus allowing normal embryo development. Similar influence of microspore developmental stage on microspore embryogenesis has been reported in 24 PREM, GUPTA AND AGNIHOTRI B. campestris [80,82], B. carinata [75], and B. juncea [66,77,83,85]. These studies have established that the late uninucleate stage is most responsive to embryogenesis and that selection of buds with majority of late uninucleate microspores increases the frequency of embryo formation in isolated microspore culture in oilseed brassicas.…”

“…Many laboratories have developed specialized protocols for isolated microspore culture of B. napus [56,[70][71][72][73][74]. Several reports on isolated microspore culture have also been published in B. carinata [18,70,75], B. nigra [76,77], B. campestris [62,76,[78][79][80][81][82][83] and B. juncea [23,77,[83][84][85][86][87]. However, apart from B. napus, limited success has been achieved in other species towards cultivar development, due to the lack of efficient microspore embryogenesis.…”

“…Genotypic variations in haploid embryo development have been observed in several brassica species [88]. Genotypic variability for microspore embryogenesis response in isolated microspore culture has been reported in B. campestris [18,79,80,82], B. juncea [23,77,85] and in most reports sited for B. napus above. Recently microspore embryogenic ability has been studied as a stably inherited trait using the diallele mating system in B. napus by Zhang and Takahata [89].…”

“…Limited reports are available on the influence of donor plant's growth condition on microspore embryogenesis in B. juncea. A relatively higher temperature regime (20-21°C day/15-18°C night) has been reported to be congenial for microspore embryogenic response in isolated microspore cultures of B. juncea [23,77,85]. In view of this it seems likely that the plants may be grown under normal in vivo temperature conditions for healthy and vigorous vegetative growth, however, a shift to lower temperature regime is essential for enhancing microspore embryogenic response.…”

Microspore Culture and Doubled Haploid Technology

“…In B. napus , B. rapa ssp. pekinensis and B. juncea , genotypes of spring type, which bolts irrespective of chilling exposure, showed high response of embryogenesis (Ohkawa et al 1987 ;Kuginuki et al 1997 ;Hiramatsu et al 1995 ;Ferrie 2003 ). On the other hand, Keller et al ( 1987 ) reported that winter types had a high response in anther culture of B. napus .…”