The occurrence of heat waves in the Midwest is becoming more common and affects specialty crop production. Within flowers, between the male and female parts, the male tissues (anthers and pollen) are more sensitive to heat stress. Heat stressed flowers often produce abnormal or aborted pollen grains and negatively impacts plant reproduction and development of fruits and seeds. During abiotic stress, plant cells allocate resources towards protection thus splitting resources with primary metabolism. Much of our knowledge regarding this comes from studying leaf cells but further studies are needed to understand how plant reproductive tissues, specifically anthers, balance the two processes to produce viable pollen grains for successful fruit and seed formation. The Santiago laboratory seeks to better understand how plants adjust their primary metabolism in sink tissues during high temperature stress. Using physiological and biochemical techniques, we dissect carbon and nutrient metabolism and transport in anthers and pollen grains under elevated temperature conditions to identify key mechanisms that contribute to reproductive thermotolerance. Ultimately, it is our goal to use findings in this research to develop climate resilient crops to future-proof specialty crop production in Illinois.
Aside from studying the physiological and biochemical basis of thermotolerance in flowers, we are also interested in finding sustainable solutions to reduce or eliminate the effects of heat stress in flowers.
Growing crops in protected structures had been practiced since the time of ancient Rome but it was only in the past few decades that technology was used in protected agriculture incorporating controls in lighting, temperature, humidity, and irrigation. In recent years, increased consciousness regarding food mileage and sustainability, and the need for fresh produce encouraged further growth of indoor agriculture resulting in opening of large greenhouses and vertical farms that produce leafy greens and culinary herbs close to large cities. One limitation of indoor grown crops, however, is lack of nutrient density in plants like lettuce that is popularly grown in plant factories with artificial lighting or vertical farms. The second limitation of indoor farming is lack of crop diversity. In the Santiago lab, we are exploring the manipulation of cultural and environmental parameters to promote plant yield and the accumulation of health-promoting metabolites in leaves. Furthermore, we aim to identify regulators that control metabolite accumulation to provide the basis for development of new cultivars through traditional breeding or biotechnological approaches. Finally, we are exploring crop diversification under controlled environment production settings.
16. Prado K, Holland BL, Gardener BM, Lundquist P, Santiago JP, VanBuren R, Rhee SY (2025) Enhancing crop resilience against drought and heat stress through an integrated field-to-lab-to-field research paradigm. Journal of Experimental Botany, 76(16): 4395-4413 (Darwin Review)
15. Walters J, Fisher R, Sharkey TD, Isaacs R, Santiago JP (2025) Extreme heat affects blueberry pollen nutrition: consequences for bee health and plant fertilization. Scientific Reports, 15: 6249
14. The SV, Santiago JP, Pappenberger C, Hammes UZ, Tegeder M (2024) UMAMIT44 is a key player in glutamate export from Arabidopsis chloroplasts. The Plant Cell, 36:1119-1139
13. Lucas M, Santiago JP, Chen J, Guber A, Kravchenko A (2023) The soil pore structure encountered by roots affects plant-derived carbon inputs and fate. New Phytologist 240(2): 515-528
12. Welker S, Pierre M, Santiago JP, Dutt M, Vincent C, Levy A (2022) Phloem transport limitation in Huanglongbing affected sweet orange is dependent on phloem-limited bacteria and callose. Tree Physiology, 42:379-390
11. Santiago JP, Soltani A, Bresson MB, Preiser AL, Lowry DB, Sharkey TD (2021) Contrasting anther glucose 6-phosphate dehydrogenase activities between two common bean (Phaseolus vulgaris) varieties suggest an important role in reproductive heat tolerance. Plant, Cell & Environment, 44: 2185-2199
10. Soltani A, Walter KA, Wiersma AT, Santiago JP, Quigley M, Chitwood D, Porch TG, Miklas P, McClean PE, Osorno JM, Lowry DB. (2021) The genetics and physiology of seed dormancy, a crucial trait in common bean domestication. BMC Plant Biology, 21: 1-17
9. Santiago JP, Ward JM, and Sharkey TD (2020) Phaseolus vulgaris SUT1.1 is a high affinity sucrose-proton co-transporter. Plant Direct 4: e00260
8. Santiago JP and Sharkey TD (2019) Pollen development at high temperature and role of carbon and nitrogen metabolites. Plant, Cell & Environment 42: 2759-2775
7. Santiago JP and Tegeder M (2017) Implications of nitrogen phloem loading for carbon metabolism and transport during Arabidopsis development. Journal of Integrative Plant Biology 59: 409-421
6. Santiago JP and Tegeder M (2016) Connecting source with sink: The role of Arabidopsis AAP8 in phloem loading of amino acids. Plant Physiology 171: 508-521
5. Santiago JP, Halteman W, and Smagula JM (2014) Determining optimum macro- and micronutrient leaf concentrations for lowbush blueberry (Vaccinium angustifoliuim Ait.) using the boundary line approach and quantile regression. Acta Horticulturae 1017: 505-514
4. Santiago JP, Dail DB, and Smagula JM (2014) Soil texture and lowbush blueberry (Vaccinium angustifolium Ait.) leaf nutrient concentration influences response to gypsum application. Acta Horticulturae 1017: 515-524
3. Santiago JP and Smagula JM (2013) Effects of nitrogen form and ratio on in vitro shoot multiplication and growth of lowbush blueberry (Vaccinium angustifolium Ait.). Acta Horticulturae 988: 129-135
2. Santiago JP and Smagula JM (2012) Gypsum rate evaluation for wild blueberry (Vaccinium angustifolium Ait.) soils. International Journal of Fruit Science 12:23-34
1. Santiago JP and Smagula JM (2012) Comparison of split or single application of gypsum for wild lowbush blueberry (Vaccinium angustifolium Ait.). International Journal of Fruit Science 12: 35-47