Kwaw-Mensah, David

Dr. David Kwaw-Mensah is an Associate Teaching Professor in the Department of Agronomy. His degrees include a Ph.D. in Agricultural Education (Extension Education), with a Ph.D. minor in Environmental Science (Soil and Water Quality), Iowa State University, 2008, M.S. in Soil Science (Soil Management), Iowa State University, 2005, M.S in Agricultural Land-use Planning, University of Pretoria, South Africa, 1996, and B.Sc. (Hons) in Agriculture (Agronomy), Kwame Nkrumah University of Science and Technology, Ghana, 1982. He joined the Agronomy Department in 2012 as a Research Associate in Soil Management and Environment, focusing on tillage system and residue management research. In 2017 he joined the Master of Science Agronomy Program as Assistant Teaching Professor and currently teaches the following courses in the Master of Science Agronomy Program: Agronomy 532 (Soil Management), Agronomy 512 (Soil-Plant Environment), Agronomy 592 (Current Issues in Agronomy), and Agronomy 599M (Creative Component). Dr. Kwaw-Mensah also teaches a section in the undergraduate course Agronomy 342 (World Food Issues: Past and Present). He is a passionate teacher who believes in a respectful and inclusive learning environment. His teaching philosophy is grounded in the theory of transformative learning and constructivism. He shares in the thoughts of the 450 BC Philosopher, Confucius who once said, “Tell me, and I will forget; Show me, and I may remember; Involve me and I will understand.” He believes learning is an active lifelong biological process, which must be objectively evaluated using both formative and summative methods. He believes in engaging his students by telling, showing, and actively involving them in the learning and discovery process.

 

Bhattacharyya, Madan

Bhattacharyya Lab is engaged in studying the molecular bases of two serious soybean diseases; the sudden death syndrome (SDS) and root and stem rot that are caused by Fusarium virguliforme and Phytophthora sojae, respectively. They have shown that FvTox1, a phytotoxin produced by F. virguliforme is involved in foliar SDS development. They then showed that by expressing an anti-FvTox1 plant antibody or FvTox1-interacting synthetic peptides one can enhance SDS resistance in soybean plants. They have mapped several quantitative trait loci governing SDS resistance and de novo sequenced F. virguliforme to identify pathogenicity genes involved in SDS development. They have shown that overexpression of two soybean genes, which are suppressed by F. virguliforme infection, enhances SDS resistance in transgenic soybean lines. One of these genes enhances resistance of soybean also against soybean aphids, spider mites and soybean cyst nematode. They have cloned the complex Rps1-k locus that governs the race-specific resistance of soybean against P. sojae pathotypes or races. There are two highly similar CC-NB-LRR-type genes in the Rps1-k locus that have been conferring Phytophthora resistance in soybean since 1980s. They have mapped several Rps genes including Rps1-k, Rps4, Rps6, Rps8, Rps12 and Rps13.

Bhattacharyya lab is also involved in understanding the nonhost resistance mechanisms of Arabidopsis against F. virguliforme and P. sojae. They identified 14 Arabidopsis mutants that are susceptible to both pathogens; and have cloned five genes that govern nonhost immunity of Arabidopsis against the two soybean pathogens. It appears that nonhost resistance mechanisms are highly complex and expression of these genes in transgenic soybean plants enhances SDS resistance.

Chen, Yu-Ru

Yu-Ru Chen’s research focuses on genetic improvement of the haploid inducers and understanding haplotype sharing of the critical inducer founder lines. Double haploid technology in maize has contributed significantly to the genetic gain of maize in 21 centuries. The haploid inducers play a vital role in the mass production procedure of DH lines in the field, producing plentiful seeds with haploid embryo economically. There are 2 major genes/QTL involved in the haploid induction that had been cloned and identified. However, the haploid induction ability might also be controlled by other major/minor QTL, which allows for breeding the cutting-edge haploid inducers in the future. Therefore, Yu-Ru is now evaluating the genomic prediction approaches for the efficient and effective selection of haploid inducers and analyzing the key genome regions to understand haplotype sharing among those key ancestors of haploid inducers at ISU.