High Atmospheric CO Concentration Mitigates Drought Effects on an Important Grassland Weed in South America.

The differential growth and yield response of plant species to rising carbon dioxide concentrations and climatic change may alter species diversity within biomes. The Pampa Biome in South America is an important grassland biome of agronomic and environmental importance. (Chirca) is one of the most important weeds in natural pasture areas widely distributed in southern South America and can adversely affect livestock production.

Evolutionary and social consequences of introgression of nontransgenic herbicide resistance from rice to weedy rice in Brazil.

Several studies have expressed concerns about the effects of gene flow from transgenic herbicide-resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone-resistant rice (IMI-rice) cultivars increased the rice grain yield by 50% in southern Brazil.