The Systems Plant Physiology program is developing crops with enhanced nutritional qualities and identifying new methods to improve environmental attributes. This program focuses on plant biology and its integrations with micro and macro environments, utilizing physiological, molecular, or metabolic traits to understand associated biological processes. Our broad goal is developing crop varieties with enhanced crop productivity, nutritional qualities and tolerance to abiotic stresses for greater adaptability. The critical areas of research we focus on are:
- Nitrogen use efficiency, nitrogen sensing, transport and assimilation
- Molecular and genetic aspects of plant metabolism
Advancing the Sustainability Practices of Organic Vegetable Production
Poor productivity of organic crops is in part attributed to the lack of nutrient management strategy, a lack of genetics designed for optimal utilization of resources, and ineffective methods to enhance nutrient uptake. To improve yield stability, we are investigating biochemical aspects of nutrient uptake, their interactions with soil microbiomes and evaluation of nutraceutical potential of organic vegetables for human consumption and processing.
Enhancing the Nutraceutical Potential of Plants
Non-protein amino acid “citrulline” is universal in animals, plants, bacteria, and fungi. It has extensive clinical and therapeutic implications for human and animal health. We focus on many intriguing aspects of its metabolism; such as synthesis, regulation, long-distance transport, its role as an N-carrier, and as an osmolyte using molecular and metabolic cues. We are using Arabidopsis and watermelon systems to characterize citrulline metabolism.
Enhancing the nutrient use efficiency of plants
The leaching of excessive nitrogenous fertilizers applied to commercial crops leads to environmental problems. To understand the dynamics of nutrient use efficiency we are using cutting-edge tools in genomics to identify spinach genotypes efficient in nutrient uptake, assimilation, utilization. We are using natural variation as a tool to identify the genetic variation for the anti-microbial compounds in spinach and variation in the indigenous microbiota for it’s effectiveness against food-borne pathogens.
Dr. Vijay Joshi
Assistant Professor of Systems Plant Physiology
(* corresponding author)
- Canarejo-Antamba M, Banuelos-Tavares O, Reyes-Trejo B, Espinosa-Solares T, Joshi V, Guerra- Ramirez D (2021) Comparison of nutritional and nutraceutical properties of Chenopodium quinoa cultivated in Mexico and Ecuador. Chilean Journal of Agricultural Research. 81, 04. Accepted [Impact Factor: 1.67]
- Joshi V*, Penalosa A, Joshi M, Rodriguez S (2021) Regulation of oxalate metabolism in spinach revealed by RNA-Seq-based transcriptomic analysis. International Journal of Molecular Sciences. 22, 5294. https://doi.org/3390/ijms22105294 [Impact Factor: 5.92]
- Awika HO, Mishra A, Gill H, DiPiazza J, Avila C, Joshi V*(2021) Selection of nitrogen responsive root architectural traits in spinach using machine learning and genetic correlations. Scientific Reports. 11, https://doi.org/10.1038/s41598-021-87870-z [Impact Factor: 4.38]
- Song Q, Joshi M, Wang S, Johnson C, Joshi V* (2020)Comparative analysis of root transcriptome profiles of sesame (Sesamum indicum) in response to osmotic stress. Journal of Plant Growth https://doi.org/10.1007/s00344-020-10230-0 [Impact Factor: 4.17]
- Song Q, Joshi M, Joshi V* (2020) Transcriptomic analysis of short-term salt stress response in watermelon seedlings. International Journal of Molecular Sciences21, 6036. https://doi.org/10.3390/ijms21176036 [Impact Factor: 5.92]
- Song Q, Joshi M, DiPiazza J, Joshi V* (2020) Functional relevance of citrulline in the vegetative tissues of watermelon during abiotic stresses. Frontiers in Plant Science. https://doi.org/10.3389/fpls.2020.00512 [Impact Factor: 5.75]
- Joshi V*,Joshi M, Penalosa A (2020) Comparative analysis of tissue-specific transcriptomic responses to nitrogen stress in spinach (Spinacia oleracea). PLOS ONE. 15, e0232011 https://doi.org/10.1371/journal.pone.0232011 [Impact Factor: 3.24]
- Shi T, Joshi V, Joshi M, Vitha S, Gibbs H, Wang K, Okumoto S (2019) Broad-spectrum amino acid transporters ClAAP3 and ClAAP6 expressed in watermelon fruits. International Journal of Molecular Sciences. 20(23) pii: E5855 https://doi.org/10.3390/ijms20235855[Impact Factor: 5.92]
- Awika HO, Cochran K, Joshi V, Bedre R, Mandadi KK, Avila CA (2019) Single‐marker and haplotype‐based association analysis of anthracnose (Colletotrichum dematium) resistance in spinach (Spinacia oleracea). Plant Breeding.139 (2): 402–18 https://doi.org/10.1111/pbr.12773 [Impact Factor: 1.83]
- Joshi V, Shinde S, Nimmakayala P, Abburi VL, Alaparthi SB, Lopez-Ortiz C, Levi A, Panicker G, Reddy UK (2019) Haplotype networking of GWAS hits for citrulline variation associated with the domestication of watermelon. International Journal of Molecular Sciences. 20, 5392 https://doi.org/10.3390/ijms20215392[Impact Factor: 5.92]
- Joshi V*, Joshi M, Silwal D, Noonan K, Rodriguez S, Penalosa A (2019) Systematized biosynthesis, and catabolism regulates citrulline accumulation in watermelon. 162: 129-140. https://doi.org/10.1016/j.phytochem.2019.03.003 [Impact Factor: 4.07]
- Joshi V*, Fernie A (2017) Citrulline Metabolism in Plants. Amino Acids49(9): 1543-1559 https://doi.org/10.1007/s00726-017-2468-4 [Impact Factor: 3.52]
- Huang T, Joshi V, Jander G (2014) The catabolic enzyme MGL methionine gamma-lyase limits methionine accumulation in potato tubers. Plant Biotechnology Journal.12(7): 883-893 https://doi.org/10.1111/pbi.12191 [Impact Factor: 9.80]
- Adio AM, Casteel CL, De Vos Martin, Kim J, Joshi V, Li B, Juéry C, Daron J, Kliebenstein DJ, Jander G. (2011) Biosynthesis and defensive function of Nδ-acetylornithine, a jasmonate-induced Arabidopsis metabolite.Plant Cell. 23(9):3303 https://doi.org/10.1105/tpc.111.088989 [Impact Factor: 11.28]
- Jander G, Joshi V(2010) Deciphering the biosynthesis of aspartate-derived amino acids in plants: Metabolic networks and molecular mechanisms. Molecular Plant 3:54-65 https://doi.org/10.1093/mp/ssp104 [Impact Factor: 13.16]
- Joshi V*, Joung J, Fei Z, Jander G (2009) Transcriptional regulation and synthesis of branched chain amino acids as osmolytes in plants under drought and cold stress. Amino Acids.39(4):933-47 https://doi.org/10.1007/s00726-010-0505-7 [Impact Factor: 3.52].
- Joshi V, Jander G (2009) Arabidopsis thaliana methionine gamma-lyase is regulated according to isoleucine biosynthesis needs but plays a subordinate role to threonine deaminase. Plant Physiology. 151:367-378. https://doi.org/10.1104/pp.109.138651[Impact Factor: 8.34].
- Jander G, Joshi V (2009) Aspartate-derived amino acid biosynthesis in Arabidopsis thaliana. The Arabidopsis Book, Rockville, MD: American Society of Plant Biologists 7, e0121 https://doi.org/10.1199/tab.0121Open Access.
- Joshi V, Laubengayer K, Schauer N, Fernie A, Jander G (2006) Two Arabidopsis threonine aldolases are non-redundant and compete with threonine deaminase for a common substrate pool. Plant Cell. 18: 3564-3575. https://doi.org/10.1105/tpc.106.044958[Impact Factor: 11.28]
- Jander G, Norris SR, Joshi V, Fraga M, Rugg A, Yu S, Li L, Last R (2004) Application of a high throughput HPLC-MS/MS assay to Arabidopsis mutant screening; evidence that threonine aldolase plays a role in seed nutritional quality. Plant Journal.39 (3) 465-475. https://doi.org/10.1111/j.1365-313X.2004.02140.x [Impact Factor: 6.42].
- Telang M, Srinivasan A, Patankar A, Harsulkar A, Joshi V, Damle A, Deshpande V, Sainani M, Ranjekar P, Gupta G, Birah A, Rani S, Kachole M, Giri A, Gupta V (2003) Bitter gourd proteinase inhibitors: potential growth inhibitors of Helicoverpa armigeraand Spodoptera litura. 63(6) 643-652 https://doi.org/10.1016/S0031-9422(03)00239-5 [Impact Factor: 4.07].
- Joshi V*, Ugale SD (2002) Involvement of higher order gene interactions addressing complex polygenetically controlled the inheritance of downy mildew (Sclerospora graminicolaS), resistance in pearl millet (Pennisetum glaucum). 127(2): 149-161 https://doi.org/10.1023/A:1020220309074 [Impact Factor: 1.90]
- Grant #1