IN VITRO REGENERATION OF FIVE WHEAT GENOTYPES FROM

IMMATURE ZYGOTIC EMBRYOS

 

MUHAMMAD ILYAS KHOKHAR^1*, MUHAMMAD ZAFFAR IQBAL¹

AND JAIME A. TEIXEIRA DA SILVA²

 

¹Agricultural Biotechnology Research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan

² P. O. Box 7, Miki-cho post office, Ikenobe 3011-2, Kagawa-ken, 761-0799, Japan

^*Corresponding author’s email: khokharab@yahoo.com, ilyasabri@yahoo.com

 

Abstract

 

This study examined the ability to induce callus from immature zygotic embryos of five wheat genotypes (Lu 26, WH 543, Zamindar 80, BT-002 and Seher-06) in response to 2, 4 and 6 mg/L of 2,4-dichlorophenoxy acetic acid (2,4-D). Callus induction was most effective (41% averaged across the 5 genotypes) in the presence of 2 mg/L 2,4-D. Callus induction was highest in Lu 26 (34%) followed by WH 543 (33%). Highest percentage shoot formation (33%) from callus was possible on Murashige and Skoog (1962) medium containing 300 mg casein hydrolysate. BT-002 responded best to shoot formation (26%) followed by WH 543 (24%). Under these optimal conditions, callus could form within 7.4 days and shoots within 20.87 days (fastest growth averaged across the 5 genotypes). Zamindar-80 responded best by taking fewest days to initiate callus formation (7.88 days) while Lu 26 took the least amount of time to form shoots (23.25 days). This study provides a rapid and efficient, as well as cultivar-independent protocol for the indirect formation of shoots from callus, the first such report for WH 543, Zamindar 80, BT-002 and Seher-06. This protocol may be a useful protocol for transgenic wheat plants that are derived from the genetic transformation of callus, either by particle bombardment or Agrobacterium-mediated transformation, to produce, for example, insect- or herbicide-resistant plants, since a rapid and effective regeneration protocol is an essential first step for the successful regeneration of transgenic plants.

 

Key words: Callus induction; Casein hydrolysate; 2, 4-dichlorophenoxy acetic acid (2, 4-D); Shoot formation; Wheat.