Theses and Dissertations



Dhillon, Jagmandeep

Committee Member

Cox, Michael S.

Committee Member

Bheemanahalli, Raju

Committee Member

Li, Xiaofei

Committee Member

Reddy, Krishna N.

Date of Degree


Original embargo terms

Embargo 2 years

Document Type

Dissertation - Open Access


Plant and Soil Sciences (Agronomy)

Degree Name

Doctor of Philosophy (Ph.D)


College of Agriculture and Life Sciences


Department of Plant and Soil Sciences


Three studies were conducted with the objectives as i) to assess the impact of climate change on Mississippi (MS) corn production using 1970 to 2020 datasets, employing autoregressive distributed lag model (ARDL), ii) A narrative review on the role of sulfur (S) in crop production, and iii) to investigate the corn response to multiple rates of nitrogen (N) and S. The first study findings revealed that the maximum temperature and precipitation had a negative effect on MS corn yield while minimum temperature and CO2 emissions posed a positive effect on corn yield. The second review study discussed the need for exploring the improvements required in S uptake, S use efficiency, systematic S fertilizing strategies, and precise and timely S diagnostic tools. Third study was a field experiment conducted at four-site years in 2021 and 2023 at Starkville, Brooksville, and Stoneville, Mississippi (MS) using a randomized complete block design with four replications. Treatments included 0, 112, 224, and 336 kg N ha-1 and 0, 22, 44, and 66 kg S ha-1, and their interactions. The key findings of this study were i) N x S interaction affected S agronomic efficiency (SAE) and S partial factor productivity (SPFP) at all site-years, N partial factor productivity (NPFP) at 2 site-years, and N leaf uptake (NLF), ear height, and grain oil at 1 site-year, ii) N-only treatments influenced grain yield, N agronomic efficiency (NAE), N grain uptake (NGR), protein, starch, seed index at all site-years, N uptake in leaf (NLF) and S uptake in leaf (SLF) at 3 site-years, and N partial factor productivity (NPFP), plant and ear height, stalk diameter, leaf area index (LAI), grain oil and S uptake in grain (SGR), at 2 site years, iii) S only treatments influenced starch at 2 site-years, and grain yield, N agronomic efficiency (NAE), protein, seed index, N uptake in grain (NGR), and S uptake in leaf (SLF) at 1 site-year. Although the response of S was less frequent at all the tested parameters, current findings indicated the vitality of S fertility for all parameters except growth parameters.

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