AUTHOR=Das Alok , Datta Subhojit , Thakur Shallu , Shukla Alok , Ansari Jamal , Sujayanand G. K. , Chaturvedi Sushil K. , Kumar P. A. , Singh N. P. 

TITLE=Expression of a Chimeric Gene Encoding Insecticidal Crystal Protein Cry1Aabc of Bacillus thuringiensis in Chickpea (Cicer arietinum L.) Confers Resistance to Gram Pod Borer (Helicoverpa armigera Hubner.)

JOURNAL=Frontiers in Plant Science

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2017.01423

DOI=10.3389/fpls.2017.01423

ISSN=1664-462X

ABSTRACT=<p>Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer (<italic>Helicoverpa armigera</italic> H.) wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by <italic>Bt</italic> (<italic>cryI</italic>) genes. We designed a plant codon optimized chimeric <italic>Bt</italic> gene (<italic>cry1Aabc</italic>) using three domains from three different <italic>cry1A</italic> genes (domains I, II, and III from <italic>cry1Aa</italic>, <italic>cry1Ab</italic>, and <italic>cry1Ac</italic>, respectively) and expressed it under the control of a constitutive promoter in chickpea (<italic>cv</italic>. DCP92-3) to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The <italic>in vitro</italic> regenerated (organogenetic) shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L) with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering) were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay) led to identification of efficacious transgenic chickpea lines. The chimeric <italic>cry1Aabc</italic> expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.</p>