Horticulture Commons^™

Cytokinins, Gibberellins, And Ethylene On Plant Form And Flowering In Streptocarpus, Rachel Bobo

Theses and Dissertations

Plant form and flowering of Streptocarpus x hybridus Ladyslippers® ‘Grape Ice’ and ‘Deep Blue Vein’ were examined in response to exogenous application of ethephon [(2-chloroethyl) phosphonic acid], gibberellin 3 (GA3), benzyladenine (BA), and growth retardants ancymidol and chlormequat chloride. 750 mg L-1 ethephon applied at 3 weeks post-transplant (WPT) is effective in chemically pinching premature floral buds, delaying flowering by up to 10 days without restricting final plant size. Early applications of GA3 and BA hasten flowering by up to 10 days. GA3 and BA also interacted to promote floral development when applied early in the production cycle; increasing flower …

The Effect Of Stem Recutting And Floral Food On Vase Life Of Zinnias Elegans, Lauren Elise Baskin

Theses and Dissertations

A recent shift in the cut flower market focuses on locally produced cut flowers, creating interest in the consumer mind. The vase life of these cut flowers varies by variety and species. Knowing the proper post-harvest protocol is crucial information, as this affects flower’s longevity. This research used a 2x2x2 factorial design examining the zinnias variation in vase life between the following test groups: zinnias with trimmed and untrimmed stems in tap water and trimmed and untrimmed stems in floral food solution. The results of the study indicated that zinnias placed in a floral food solution and were trimmed have …

Evaluation Of Critical Nitrogen Requirements For Commercial Tomato Production In Mississippi, Prakash Khanal

Theses and Dissertations

Optimizing nitrogen (N) management is critical for tomato production, as crop requirements vary with soil, climate, and production practices. Despite the importance of tomato in Mississippi, region-specific N recommendations remain limited. Field studies (2024-2025) and a high tunnel study (2025) were conducted at the North Mississippi Research and Extension Center to determine critical N rates for fresh-market tomato. Six N rates were evaluated using a randomized complete block design with four replications. Results provide system-specific guidance, highlighting differences in N requirements between open-field and high tunnel production. Tailoring N inputs to production environments can improve yield and fruit quality, enhance …

Discovering The Genetics Underlying Speciation Traits In Heuchera (Coral Bells), Tajinder Singh

Honors Theses

Hybridization is a key evolutionary mechanism for generating biological diversity, ultimately shaping diversification and adaptation of plant lineages in natural and agroecosystems.  Our understanding of the frequency, distribution, and significance of hybridization is rapidly increasing, but the external driving forces that dictate why certain species hybridize, and others do not remain obscure. The physical traits that shape gene flow and trait sharing among species are likely to be among the key factors that directly control hybridization. Gene flow in most plants is mediated by pollinating insects and thus by pollination syndromes, which are suites of floral traits that have evolved …

Evaluation Of Plant Growth Regulators On Sweetpotato Slip Propagation, Kerington Lyn Bass

Theses and Dissertations

Sweetpotato production is often impacted by high mortality of slips during transplantation to the field, particularly with greenhouse-grown slips. These slips develop thinner stems, thus being more vulnerable to transplant shock, resulting in reduced establishment. To address this issue, the study evaluated the effects of four plant growth regulators on the morphological and anatomical characteristics of sweetpotato slips. In the first experiment, external growth parameters were recorded over four weeks, followed by post-harvest assessments of plant and root material. In the second experiment, the widths of various stem structures in stained cross-sections of slip stems were measured. Results showed that …

Using Cutting Immersion To Apply Rooting Hormone For Propagation Of Camellia Japonica., Tanner R. Marlow, Richard L. Harkess

Honors Theses

Few varieties of Camellia japonica have a high success rate in rooting cuttings. Once rooted, the subsequent growth rate is slow and differs by variety. This makes the commercial production of Camellia challenging. Previous research on C. japonica propagation confirms that using a basal cut dip in indole-3-butyric acid (IBA) is effective in rooting C. japonica. However, basal dip applications can be time-consuming. Foliar applications and total cutting immersion are more efficient methods of rooting hormone application, but they have not been thoroughly tested with Camellia. The objective of this research was to determine the effective IBA concentration applied as …

Soil Health As Influenced By The Integration Of Cover Crops And Poultry Litter In North-Central Mississippi, Nikitha Reddy Kovvuri

Theses and Dissertations

Soil health-based agricultural management practices are widely promoted to improve soil structure, infiltration and reduce erosion. This study was conducted at two locations in North-Central Mississippi to evaluate the influence of different cover crop species and poultry litter on soil health that can impact crop production, climate change, and resilience. The results indicated that the cover crops showed a little effect on some soil health indicators compared to control treatment. However, in one location, rye, and a mixture of cover crops decreased bulk density and increased available water content and organic matter. The poultry litter had a positive effect on …

Response Of Lettuce (Lactuca Sativa L.) To Salt Stress, Bikash Adhikari

Theses and Dissertations

Lettuce is a highly nutritional crop that is sensitive to multiple stresses, including salt stress. The decreasing availability of salt-free water is posing a major challenge to growing nutritious lettuce in hydroponic systems. Despite evidence that salt stress affects yield and nutrition, its impacts on economically important growth stages are overlooked. This study addressed the knowledge gaps regarding the salt stress impact on romaine lettuce. Four independent experiments were conducted in controlled environment conditions using 2-38 lettuce genotypes, to assess the effects of salt stress at rosette or head formation. An increase in sodium chloride (NaCl) levels (0 to 150 …

Impacts Of Cover Crop, Soil Steaming, And Plastic Mulch On Field-Grown Tomato Production And Virus-Induced Gene Silencing In Antirrhinum, Penstemon, Petunia, Rosa, And Rudbeckia, Brenton Andrew Earl Breland

Theses and Dissertations

Weeds and soil-borne diseases can cause large yield losses in field-grown tomato (Solanum lycopersicum) production. Techniques have been developed to reduce soil-based problems. In this study, we evaluated the impacts of cover crops, soil steaming, and plastic mulch to reduce weed and disease pressure in field-grown tomatoes. Four cover crop treatments were grown in the fall and winter before spring planting. Soils were steamed to a target temperature of 71.1 °C for 0, 5, or 20 minutes. Plastic mulch was also used on half of the rows. Yield, weed densities, and disease incidence were recorded.

Reduced flowering time …

The Influence Of Overwatering, Underwatering, And Waterlogging On The Growth Of Kale (Brassica Oleracea Var. Acephala), Skyler R. Brazel

Theses and Dissertations

The Intergovernmental Panel on Climate Change has predicted that there will be increases in precipitation and heat-induced drought events globally. Information on kale response to waterlogging is minimal. The purpose of this project was to identify the response of kale to three treatments of water stress: underwatering, overwatering, and waterlogging. Plant pigments analyzed displayed a varied response to underwatering and overwatering, with concentrations changing with maturity but with reductions and no changes, respectively, at full harvest maturity. Glucosinolate concentrations were also influenced by maturity and increased under waterlogging and underwatering but no differences with overwatering. Overall, water stress to any …

Examining Physiological And Photosynthetic Effect Of Led Lighting On Lettuce And Kale Microgreens, James Travis Blanche

Theses and Dissertations

The objective of these studies was to observe the effects of LED lighting treatments on physiological parameters of lettuce and microgreens. Four different lighting treatments; 1) Physiospec (white), 2) Red, 3) DR9 (25:75 Blue:Red), and 4) Anthospec (at 20/80 Blue:Red); were used in this experiment. Two experiments were conducted: 1) Examining the effects of LED lights on lettuce yield and photosynthetic activity and 2) The effects of switching lighting regiments halfway through the growth cycle on Kale microgreen yield and color. Physiospec lighting was found to promote the highest yield and photosynthetic activity among the four treatments for lettuce. It …

Non-Traditional Adjuvants And Methods For Applying Root-Promoting Compounds In Commercial Cutting Propagation, Anthony Turner Bowden

Theses and Dissertations

The nursery/greenhouse industry is innovative. There have been several reports in the popular literature of non-traditional adjuvants used in plant propagation; however, these claims have never been evaluated in a scientific setting. Five studies, conducted at the South Mississippi Branch Experiment Station in Poplarville in 2019 and 2021 determined the impact that adding honey to water-soluble auxin solutions and surfactants to foliar applied auxin solutions on physiological responses associated with adventitious root formation. Treatments in studies presented in chapters two and three included three honey sources (multiflora, local, and Manuka). Honey-infused water-soluble auxin solutions affected plant species but not in …

Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur

Theses and Dissertations

Sustainable practices were evaluated for the production of two warm season vegetable crops, tomato and chile peppers. The first study investigated the plant vegetative growth, fruit production timing, yield components and fruit quality of three hybrid and three heirloom tomato cultivars grown in a high tunnel using grafted and non-grafted plants. Grafting the selected tomato cultivars with the two rootstock types did not alter total marketable yield of any cultivar, but affected overall stem diameter, fruit color, and β-carotene concentrations of tested tomato cultivars. The second study evaluated the plant growth, yield, and fruit quality of nine heirloom chile pepper …

Effects Of Pruning Timing, Leaf Removal, And Shoot Thinning On 'Midsouth' Winegrape Quality In South Mississippi, Haley Nicole Williams

Theses and Dissertations

‘MidSouth’, a relatively low maintenance interspecific hybrid bunch grape currently grown in South Mississippi, has low sugar and high acid levels for red wine use. Two studies, conducted at the Mississippi State University McNeill Research Unit in 2020 and 2021, determined the effects of pruning timing, leaf removal, and shoot thinning on ‘MidSouth’ development and fruit and wine quality. Treatments in the first study included early versus normal pruning timing, both with and without leaf removal, and treatments in the second study included leaf removal, shoot thinning, and control vines. Cluster temperatures, leaf chlorophyll, berries per cluster, berry and cluster …

Proceedings Of The 2022 Passion Fruit Conference: Growing The U.S. Passion Fruit Industry A Strategic Conference For: Growers, Marketers, Researchers, And Stakeholders, Eric T. Stafne

CREC Publications

We are pleased to deliver these proceedings of the passion fruit conference that was held in Homestead, Florida on June 14 and 15, 2022. It was a culmination of a lot of hard work by many people, most of them listed in the previous page. However, it would not have been a success without the attendees who came from various parts of the country to share their experiences growing passion fruit. What follows in these proceedings are the slides of the presentations with by notes taken by attendees along with notes taken of discussion regarding the five priority topic areas: …

Evolution Of Genome Size And Complexity In Pinus., Alison M. Morse, Daniel G. Peterson, M. Nurul Islam-Faridi, Katherine E. Smith, Zenaida V. Magbanua, Saul A. Garcia, Thomas L. Kubisiak, Henry V. Amerson, John E. Carlson, C. Dana Nelson, John M. Davis

CALS Publications

BACKGROUND: Genome evolution in the gymnosperm lineage of seed plants has given rise to many of the most complex and largest plant genomes, however the elements involved are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Gymny is a previously undescribed retrotransposon family in Pinus that is related to Athila elements in Arabidopsis. Gymny elements are dispersed throughout the modern Pinus genome and occupy a physical space at least the size of the Arabidopsis thaliana genome. In contrast to previously described retroelements in Pinus, the Gymny family was amplified or introduced after the divergence of pine and spruce (Picea). If retrotransposon expansions are responsible …