Expression of the DREB1A gene in lentil (Lens culinaris Medik. subsp. culinaris) transformed with the Agrobacterium system

Abstract

Until now three publications have reported the development of transgenic lentil plants through protocol optimisation using the gusA gene, but there are no reports of the introduction of a gene with agronomic importance. In the present study we report the introduction of the DREB1A gene into lentil to enhance drought and salinity tolerance. Decapitated embryos were immersed in Agrobacterium suspension and then co-cultivated for 4 days. Direct organogenesis was induced from the apical meristems and cotyledonary buds. Subsequently, the explants were subjected to selection in medium containing 10 mg/L phosphinothricin for nine rounds with 2-week intervals. The putative transgenic explants were micro-grafted onto non-transformed rootstocks to establish transgenic plants. The PCR results confirmed the insertion and stable inheritance of the gene of interest and bar marker gene in the plant genome. The Southern blot analysis revealed the integration of a single copy of the transgenes. T0 plants and progeny up to T2 generations showed complete resistance to the herbicide Basta. The DREB1A gene driven by the rd29A promoter was induced in transgenic plants by salt stress from sodium chloride solution. The total RNA was extracted and cDNA synthesised. The results showed that DREB1A mRNA was accumulated and thus the DREB1A transgene was expressed in the transgenic plants, whereas no expression was detected in the non-transformed parents.

Grain Legumes

“…Neither of the above reports utilized an agronomically beneficial gene in their inserted construct. Khatib et al (2011) developed a construct that included the DREB1 A gene. This gene has been reported to improve tolerance to drought, salinity, and freezing stress (Liu et al 1998;Kasuga et al 1999;Gilmour et al 2000) in Arabidopsis presumably by means of OA.…”

“…This gene has been reported to improve tolerance to drought, salinity, and freezing stress (Liu et al 1998;Kasuga et al 1999;Gilmour et al 2000) in Arabidopsis presumably by means of OA. Transformants were induced to express the DREB1 A gene and demonstrated tolerance compared to the controls when watered with a saline solution of 50 mM NaCl (Khatib et al 2011). Whether this work will result in field production of transgenic plants is uncertain.…”

Gene Transfer in Legumes

“…Most recently, in order to enhance drought and salinity tolerance, Khatib et al (2011) introduced DREB1A gene driven by the rd29A promoter into lentil decapitated embryo explants followed by shoot regeneration from the apical meristems and cotyledonary buds via direct organogenesis. Subsequently, bastaresistant putative transgenic explants were micro-grafted onto non-transformed rootstocks to establish transgenic plants.…”

Climate change and agricultural ecosystem management in dry areas

“…While farming systems on the Loess Plateau are very different from south-west Australia , the issues of increasing crop and pasture productivity with limited rainfall and increasing temperatures, are common, and are relevant to issues in other semiarid areas of the world. Thus, the papers in this special issue address the subject of increasing precipitation use efficiency (Fang et al 2011;Khatib et al 2011;Gan et al 2011aGan et al , 2011bTurner et al 2011) and increasing nutrient use efficiency Gan et al 2011aGan et al , 2011bWang et al 2011) in semiarid regions. The role of roots in increasing both precipitation and nutrient use efficiencies is highlighted Gan et al 2011aGan et al , 2011b and the different depth of rooting between the crop legumes, oilseeds and spring wheat led Gan et al (2011a) to suggest that oilseeds and wheat be grown in rotation with legumes to maximise precipitation use efficiency in water-limited environments.…”

“…The DREB genes hold promise of increasing the drought and cold resistance of crops (BhatnagarMathur et al 2007). In the paper by Khatib et al (2011) the methodology for introduction of the dreb 1a gene into lentil (Lens culinaris), a recalcitrant species for transformation, is developed and its expression confirmed. The success of the introduction in terms of increasing the drought tolerance of lentil has still to be confirmed and validated in practical plant breeding programs, but it is an example of the progress being made in improving the drought resistance of crops through molecular biology and crop genomics.…”