relation: http://oar.icrisat.org/4776/ title: Factors affecting high frequency differentiation of shoots and roots from cotyledon explants of Brassica juncea (L.) czern creator: Sharma, K K creator: Bhojwani, S S creator: Thorpe, T A subject: Soil Science subject: Plant Pathology description: Studies were undertaken to optimize conditions for high frequency shoot regeneration from excised cotyledons of Brassica juncea cv. RIK-81-1. Maximum differentiation of adventitious shoot buds occurred when the explants derived from 5-day-old seedlings were cultured on Murashige and Skoog medium (MS) containing 5 μM N6-benzyladenine (BA). On MS alone only roots were formed. Shoot or root formation was restricted to 1–2 mm of tissue at the cut end of the petiole. Organogenesis occured only if the proximal cut end of the petiole was in contact with the medium. The lamina did not exhibit organogenesis. Cotyledons cultured for up to 3 days on root induction medium (MS), still retained their full potential to form shoots upon transfer to MS + BA. With longer incubation on MS medium the shoot-forming capacity of the explants declined, and after 8 days it was completely lost. When applied through the agar medium, BA (5 μM) was required for at least 7 days for shoot bud induction. The possible usefulness of B. juncea cotyledons as an experimental system for detailed studies of morphogenesis and genetic transformation is discussed publisher: Elsevier date: 1990 type: Article type: PeerReviewed format: application/pdf language: en identifier: http://oar.icrisat.org/4776/1/Plant_Sc_66_2_247-253_1990.pdf identifier: Sharma, K K and Bhojwani, S S and Thorpe, T A (1990) Factors affecting high frequency differentiation of shoots and roots from cotyledon explants of Brassica juncea (L.) czern. Plant Science, 66 (2). pp. 247-253. ISSN 0168-9452 relation: http://dx.doi.org/10.1016/0168-9452(90)90210-F