Ondzighi-Assoume's Lab
Biotechnology and Physiology of Plants
•
Bioenergy’s Project: Improving Bioenergy Lignocellulosic Feedstock Traits Using Biotechnology in Grass
Decreasing lignin content of plant biomass by genetic engineering is believed to reduce biomass recalcitrance and improve saccharification efficiency of biomass. Our lab uses biotechnology and genome editing to engineer potential bioenergy crops ((i.e.: sorghums and switchgrass) for biofuels production. The main objectives of this grass’s project are: (i) Development and establishment of efficient cell culture systems capable of genetic transformation and regeneration, (ii) Development of reliable transformation and regeneration methods adapted with CRISPR-Cas9 technology, (iii) Editing gene(s) involved in cell wall biosynthesis, and (iiii) Development of biochemical and morphometric methods for sacharrification and adaptation of transgenic lines to the greenhouse and fields.
• Seed’s Project: Enhancing Oil Seed Quality and Production through Biotechnology in Beans (Co-direction with Dr. M. Blair)
Using Arabidopsis thaliana as a plant system model, our lab studies the biotechnology and genomics of legumes (i.e.: soybeans and Cowpeas) to improve seed quality and production of high-yield variety. These tow legumes are important agricultural crops, source of edible oils and protein in the world. Because of their high importance as a food crops, major objectives in these bean’s plants breeding; improvement of seed protein and oil quality and production need to be achieved. We potentially aim to achieve these objectives through biotechnology. The innovation of this bean’s research is to clone and characterize protein disulfide isomerases (PDIs) genes that have function in controlling seed set and size/weight, important traits for seed quality and production. We are focusing on two mains goals: (i) development of optimum techniques (i.e. CRISPR-Cas strategy) for stable genetic transformation and regeneration of bean plants over or under expressing similar PDI genes, (ii) evaluate the resulting transgenic bean plants for seed production and oil yield.
• Disease’s Project: Controlling Powdery Mildew (PM) through Biological Control Agents (BCAs) in Legumes (Co-direction with Dr. M. Mmbaga)
Cucumber and squash are legumes or cucurbit crops that have nutritional and medicinal benefits. These two crops contain essential provitamin, vitamins, and minerals such as potassium, iron, calcium, magnesium, manganese, copper, phosphorous, and calcium. In Tennessee, these cucurbit crops are affected by several major infectious diseases including anthracnose, Cercospora leaf spot, cucumber mosaic, downy mildew, Phytophthora fruit and crown rot, Septoria leaf spot, and endophyte powdery mildew which severely reduce their productivity. PM is ranked as the most severe disease of these cucurbits in US. Thus, the purpose of our study is to control/treat powdery mildew in cucumber and squash using Biological Control Agents (BCAs). BCAs are known to reduce disease incidence directly or indirectly by inhibiting the development and activities of pathogens and/or promoting plant growth. We focus on three objectives: (i) evaluation of the effect of isolated BCAs in controlling PM using weekly foliar sprays on cucumber and squash plants. (ii) Evaluation of molecular and biochemical mechanisms underlying the beneficial interactions between BCAs and their hosts cucurbits, and (iii) Identification of non-volatile secondary metabolites produced in endophyte-host interactions, endophyte-pathogen interactions.
