Glycine Max Transcriptome or Gene expression. Glycine Max

We have investigated how weeds turn genes on and off in soybeans in the field to cause loss of yield and reduced growth. We used different weeds each year and controlled weeds in our weed free plots using different herbicides so we would only detect general responses to weeds rather than any responses that might be caused by a specific weed species. We determined first that our treatments caused leaf area , plant height, and yield. After examining more than 30,000 different genes, we identified 55 that had lower concentrations and 14 that higher concentrations of corresponding transcripts (mRNA) when the soybeans were grown with weeds. Among the genes that were “turned on” by weeds was a particular gene that codes for a transcription factor (a protein that turns other genes on or off) that is called PHYTOCHROME INTERACTING FACTOR 3 (PIF3 for short). PIF genes (but not PIF3) are known to play a role in altering the development of a model plant called arabidopsis when it is grown in dense populations or when treated with excess far red light. We surmise the soybean PIF3 may act in a similar way to the arabidopsis PIFs to alter soybean growth and development in response to weeds. Since recent studies have shown that weeds could inhibit soybean growth even when they are physically separated from them and thus not competing for resources, we believe that by turning this gene off, we may be able to make soybeans blind to weeds and thus reduce the negative impact that they have on soybean growth.