For years, despite controversy, the genetically engineered insect-resistant crop plants, using Cry genes extracted from the soil bacterium —Bacillus thuringiensis (Bt) — have been perceived to be beneficial to the growth of the plants.New research by Indian scientists shows that the expression of the Bt toxin Cry1Ac in cotton and tobacco transgenics is detrimental to the growth and development of the plants.The proteins encoded by Cry genes are called Bt-toxins. They are thought to specifically affect only certain insects and not other organisms.

This interesting result observed by Dr Pradeep Burma has been published in the June issue of theJournal of Biosciences, brought out by the Indian Academy of Sciences.

DEVELOPMENTAL DEFECTS

In the scientific paper, Dr Burma and researchers from the University of Delhi, South Campus state that many of the transgenic plants obtained showed developmental defects like abnormal growth (stunting) and/or sterility.

These symptoms suggest that expression of Cry1Ac could be causing growth defects in plants, they inferred.

In line with this explanation, the researchers also found that a majority of transgenic plants had very low or undetectable levels of Cry1Ac. Further, all plants having appreciable levels of Cry1Ac showed developmental abnormalities indicating a correlation between the levels of toxin expression and the developmental defects in the plants.......Read More

Source: Business Line