The first 'Green Revolution' in the 1960s was based on dwarf varieties of wheat and rice that were capable of responding to fertilizer and irrigation without lodging. The 'Second Green Revolution' will consist of crop genotypes with superior yield with limited supplies of water and nutrients The UN estimates that about 800 million people are undernourished, and the number of malnourished people in Africa is actually growing. Agricultural production in developing nations is primarily limited by drought and low soil fertility. Fertilizer and irrigation use in these regions is low and is not likely to increase substantially in the foreseeable future because of the rising costs of fuel and therefore N fertilizer, as well as limited reserves of high-grade P ore deposits. Prospects for increased irrigation is limited by decreasing availability of clean water, and climate models predict increased crop water demand in the future. The development of crops with better growth under limited water and nutrient availability therefore has great promise to alleviate human suffering.
Our work with this topic includes crop adaptation to drought, low nitrogen availability, low phosphorus availability, manganese toxicity, and salinity. We have identified several novel root anatomical and architectural phenes (a phene is an element of the phenotype; 'phene' is to 'phenotype' as 'gene' is to 'genotype') that enhance soil exploration and the acquisition of water, N, and P. Our work in this area includes physiological characterization of the adaptive value of specific phenes, their genetic control, and their agroecological impacts. To support this effort we have developed new tools and concepts for analyzing and understanding root phenotypes, including field phenotyping platforms, laser ablation tomography to analyze plant anatomy, and the functional-structural model SimRoot. In collaboration with plant breeders, this work has resulted in the generation of new genotypes of bean and soybean with substantially better yield in low fertility soils of Africa, Asia, and Latin America.
We are also interested in how global climate change may affect ecosystems in low nutrient soils, which include most terrestrial ecosystems on earth. Very little is understood about the interaction of nutrients and other plant stress factors that may result from changing temperature, light, ozone, UV, precipitation, etc. On this topic we have ongoing research on how Mn toxicity may interact with global change variables to determine the health and composition of the Eastern forest of North America. We have discovered that Mn toxicity creates oxidative stress in tree species of the eastern forest, which means that it should change the sensitivity of these species to light, temperature, UV radiation, and ozone. Our work on this topic includes analysis of molecular, biochemical, and physiological processes in tree leaves in the forest canopy and in saplings in controlled conditions.
Our work involves a number of students and colleagues at Penn State, and collaborators from other institutions.
Kathleen Brown has retired, Jonathan Lynch is retiring in December 2023, so we are no longer accepting students and scholars into our program.
