Genetic
engineering approaches to improving nitrogen use efficiency
Ashok K. Shrawat and Allen G. Good
Since nitrogen (N) is the most essential nutrient for plants
and a major limiting factor in plant productivity, doubling
agricultural food production worldwide over the past four
decades is associated with a 20-fold increase in N
fertilizer use. Use of N fertilizers in agriculture has
already shown a number of detrimental environmental impacts.
Therefore, the need to reduce N fertilizer pollution is
strengthening the importance of improving the nitrogen use
efficiency (NUE) of crop plants. Here, we discuss recent
developments in the genetic manipulations of NUE in crop
plants.
Complete article:
pdf:
http://www.isb.vt.edu/news/2008/artspdf/may0801.pdf
web:
http://www.isb.vt.edu/news/2008/news08.may.htm#may0801
Expressing hepatitis B virus
surface antigen in rice
Janaki Krishna
Because plants may be promising bioreactors for producing
vaccines, much research is geared toward the cost effective
production of recombinant surface antigens in plants.
Researchers from Fudan University, Jiao Tong University, and
the Institute for Biological Sciences, Shanghai, China
recently reported producing a novel hepatitis B vaccine in
rice seeds.
Complete article:
pdf:
http://www.isb.vt.edu/news/2008/artspdf/may0802.pdf
web:
http://www.isb.vt.edu/news/2008/news08.may.htm#may0802
Avoiding insect resistance to Cry
toxins from Bacillus thuringiensis
Mario Soberón and Alejandra Bravo
Because 35% of crops are lost from pest damage due to
insects, fungus, bacteria, and viruses, an efficient pest
control program is an important component of any effort to
increase crop yields. One alternative to chemical
insecticides is the use of the Bt plants that express
insecticidal proteins. The most important problem that
threatens the effectiveness of Bt plants is the evolution of
resistance to Bt toxins in susceptible insects.
The high level and constitutive expression of Cry proteins
in these plants presents a selection pressure on insect
populations with increasing resistance to the toxins.
Complete article:
pdf:
http://www.isb.vt.edu/news/2008/artspdf/may0803.pdf
web:
http://www.isb.vt.edu/news/2008/news08.may.htm#may0803
