Life Sciences Commons^™

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …

Assessing Freezing Effect On Kiwifruit Cultivars And Mapping Suitable Areas For Growing The Crop In Eastern Texas, Lais De Oliveira Machado

Electronic Theses and Dissertations

Kiwifruit is a perennial vine originating from China where it has been grown for centuries. In the United States, green kiwifruit (Actinidia deliciosa) is primarily produced commercially in California. They are fuzzy, green fleshed and well known in the marketplace. Kiwifruit plants require low to moderate soil pH, adequate winter chilling and adequate precipitation to guarantee plant development and good fructification. Actinidia chinesis or golden kiwifruit are smooth skinned, feature golden flesh and are a more recent introduction into the global market. Kiwifruit crops have attributes that favor production in east Texas, including low pest problems, current long …

The Effects Of Gibberellic Acid, Smoke Water, And Cold Stratification On The Germination Of Native Perennial Seed, Zyreasha Tippins

Electronic Theses and Dissertations

In this study, I evaluated the germination rates of twenty native plant species and their response to cold stratification as well as four chemical solution treatments—water (control), gibberellic acid, smoke water, and gibberellic acid with smoke water. Seeds were evaluated and counted twice a week. Of the twenty evaluated species, sixteen had germination rates over 3% or 1 seed out of 30. Stratification increased germination by 54% when compared to the control. For chemical treatments, gibberellic acid and gibberellic acid with smoke water were significantly different from the control and increased germination by an average of 47% and 48%, respectively. …

Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson

Electronic Theses and Dissertations

Increasing evidence documenting the decline of insect populations, resulting from increasing human disturbances has resulted in efforts to establish pollinator gardens to provide additional resources for insect populations. However, our understanding of biotic and abiotic garden characteristics important for attracting and sustaining pollinator diversity is limited. Here, we evaluated 17 pollinator gardens to evaluate the effect of five biotic and three abiotic garden characteristics on pollinator species richness, abundance, and proportional representation of four pollinator functional groups. Plant species richness positively influenced pollinator richness and negatively influenced flower visitation. Bombus proportional abundance responded to several variables (distance to vegetation, plant …

Cold Climate Grape Cultivar`S Physiological And Gene Expression Responses To Low And Freezing Temperatures, Turhan Yilmaz

Electronic Theses and Dissertations

Grapevine (Vitis Vinifera), widely cultivated in the world and USA, is a significant and valuable fruit crop. After cold climate grapevine cultivars were released by breeding programs in the 1990s, the production of grapes expanded in the Northern cold climate region of the US. The objectives of this study were to test 1) freezing tolerance and chilling fulfillment, 2) the effect of pruning methods on yield and winter survival, and 3) transcriptomic changes in natural and controlled chilling conditions during chilling requirement fulfillment in cold climate grapevine cultivars. Pruning methods, spur (SP), short cane (SC), and spur plus short cane …

Evaluating The Current Weed Community In Wild Blueberry Fields And Ipm Strategies For Spreading Dogbane (Apocynum Androsaemifolium), Anthony G. Ayers

Electronic Theses and Dissertations

Lowbush blueberry (Vaccinium angustifolium) is Maine’s third largest crop (USDA 2020 a). From 2017 – 2019 the three seasons yield average was 27,200 tons were harvested from 19,500 acres for a value of $22,468,000 (USDA 2020 c). Lowbush blueberries are managed on a two-year cycle. Every other year, lowbush blueberry fields are pruned to the ground either through the use of a tractor mounted flail mower or a prescribed burn (Yarborough 2009). Pruning is a necessary part of managing lowbush blueberries as the second-year growth produces the highest yield but steadily declines in subsequent years (Drummond et al. …

Exploring Phenotypic Diversity And Quantitative Trait Loci Mapping For Root Architecture, Freezing Tolerance, Chilling Fulfillment, And Photoperiod Traits In Grapevine Populations, Dilmini Alahakoon

Electronic Theses and Dissertations

Grapevine (Vitis species) is one of the most valuable fruit crops widely cultivated throughout the United States of America (USA). Grape and wine industries in the northern USA have been expanding rapidly with the demand for quality wine grapes that can be grown in Northern cold climate regions. As most popular cultivars are freezing sensitive, the development of new cultivars for the region continues through breeding. In this study, we evaluated grapevine root system architecture, freezing tolerance, and bud break in different genetic backgrounds in natural or controlled environments. The dissertation research objectives were to explore trait phenotypic variation and …

Submist As An Effective Method For The Rooting Of Herbaceous And Woody Ornamental Plants By Stem Cuttings, Olivia Sanchez

Electronic Theses and Dissertations

The primary method of vegetative propagation by stem cutting is to insert leafy cuttings into a solid soilless media and place the cuttings in an environment that provides moist, humid conditions to the foliage through fog or overhead intermittent mist. These systems reduce water loss through transpiration by reducing leaf temperature and provide moisture to the rooting media. However, excess water, both on the media and on the leaves can result in an increase incident of diseases. To alleviate some of these issues, research has found stem cuttings can be rooted in sub-mist systems that apply water solely to the …

Establishment Of Turfgrass From Seed And Sod In Sand Based Systems Combining Sprinkler And Subsurface Drip Irrigation Systems, Roshaan Ahmed Khan Niazi

Electronic Theses and Dissertations

The establishment of turfgrass using subsurface drip irrigation (SDI) in sand based media has limited success. However, it is unknown if starting with overhead (sprinkler) irrigation and transitioning to SDI can enhance turfgrass establishment. Two experiments were conducted at Stephen F. Austin State University (SFASU) to investigate the establishment of “L-93” creeping bentgrass (Agrostis stolonifera) from seed and “TifEagle” ultra dwarf hybrid bermudagrass (Cynodon dactylon x Cynodon transvaalensis) from sod using sand based media. Each experiment consisted of two trials conducted in summer 2017 and spring 2018. Both creeping bentgrass trials and the spring ultra dwarf …

Propagation Of The Native North American Shrub Lonicera Villosa And Trait Comparisons With Nonnative Congeneric Taxa, Darren J. Hayes

Electronic Theses and Dissertations

The honeysuckles, or Lonicera, represent a circumboreally-distributed genus in the Caprifoliaceae family. A diverse assortment of vines, lianas, and shrubs comprise the genus, and honeysuckles have long been a staple of the horticultural industry, prized for their robustness as much as their sweet-scented flowers and colorful fruits. However, many cultivated honeysuckles of Eurasian origin have proven invasive outside of their native range, displacing native species and reducing overall diversity and ecosystem health. Planting of Eurasian Lonicera taxa is now often discouraged or banned throughout much of North America. Conversely, native North American Lonicera species are often sparsely distributed and …

Consumer Acceptance And Phytonutrient Assessment Of Cold Hardy, Locally Grown Plums, Amber L. Elwell

Electronic Theses and Dissertations

Prunus salicina, Japanese plums, and Prunus domestica, European plums, are naturally rich in fiber, minerals, vitamins and phytonutrients. Consuming plums can increase overall fruit intake and can be incorporated into part of a healthy diet. Through local plum production, harvesting can be completed without the need for cross-country shipping, which can increase overall acceptability and nutritional quality of the fruit. Furthermore, the increase in local production can help to boost Maine’s economy and creates a market for new plum product production.

The first objective of this study was to determine consumer acceptance of locally grown plum cultivars at a …

Flower Visitation In Relation To Pollen And Nectar Nutrition: Implications For Pollinator Habitat And Conservation, Megan E. Leach

Electronic Theses and Dissertations

Pollination of both wild and crop plants is at a crossroads; honey bee populations are experiencing losses at a higher rate than ever before, and some native bee species are declining in abundance to the point of being listed as endangered species. A few examples of these threats include pesticide exposure, habitat loss, and climate change. In response to bee population declines, conservation efforts have been initiated to increase habitat quality for bees by planting pollinator reservoirs or gardens. Plants provide nutrition to bees in the form of pollen and nectar. Several studies have shown links between higher nutritional quality …

Effect Of Pinching And Spacing On The Growth And Development Of Sunflowers (Helianthus Annuus) In East Texas, Bilawal Irshad Cheema

Electronic Theses and Dissertations

Helianthus annuus cultivars were grown in East Texas to evaluate the effect of pinching and spacing on their growth and development. The first experiment was conducted twice (Trial 1A, 28 April 2017 and Trial 1B, 3 August 2017) to evaluate the effect of pinching at nodes 1, 2, 3, and 4 on sunflower cultivars ‘Superior Gold’, ‘Pro Cut Gold’, ‘Sun Bright Supreme’, ‘Vincent’s Choice’, and ‘Sunrich Lemon’. For trial 1A, all the non-pinched treatments for the five cultivars produced marketable stem lengths, stem diameters, flower diameters, and disk diameters. For the cultivar ‘Superior Gold’ all the treatments produced marketable stems. …

Optimizing Fertilizer And Compost Rates In Organic Reduced Till Agriculture, Nicholas W. Rowley

Electronic Theses and Dissertations

Interest in reduced tillage systems has been increasing and advanced by a need to practice agriculture in a sustainable way to limit environmental degradation. The focus on preserving soil integrity has become commonplace in all scales of agriculture. Recently trends in agricultural production have given rise to numerous small farms centered on local and sustainable farming. In turn, this has led to a growing desire to implement conservation tillage into these systems.

In 2015 and 2016 a collaborative effort between the University of Maine at the Maine Agricultural and Forestry Experiment Station: Highmoor Farm and Cornell University at the Homer …

Reducing Tillage In Small-Scale Permanent Bed Organic Vegetable Production Systems, Jeremiah D. Vallotton

Electronic Theses and Dissertations

The response of field-grown vegetable crops to reduced tillage and mulching in permanent beds was evaluated through measuring crop yields, weed pressure, earthworm counts, and soil basal respiration. Two vegetable crops (“Bush Delicata” squash and “Farao” cabbage) were started in April and May of 2016 and 2017 respectively, transplanted in late June, and harvested on 15-Sep-2016 and 25-Aug-2017. Fruit number and weight of squash, and head weight and feeding damage of cabbage were measured. These results suggest that intensive tillage (8” rototill every year) can be successfully reduced to alternating years of shallow (2”) rototilling and a less intensive form …

Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett

Electronic Theses and Dissertations

Three experiments evaluated pinching and spacing on Helianthus annuus in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched plants produced marketable stem lengths and flower sizes, while pinched plants’ stem length, stem diameter, flower diameter, and disk diameter decreased compared to the non-pinched plants. The objective for experiment 2 was to evaluate pinching and spacing treatments on ‘Pro Cut Gold’ sunflowers. All spacings for non-pinched plants in experiment 2 produced marketable …

Cultivar, Season Extension, Fertilizer Trials Of Swiss Chard And Pedagogy Of Assessing Cultivars Using Technology, Chanelle Angeny

Electronic Theses and Dissertations

Abstract. Diversity of species is a cornerstone of horticulture, and the constant stream of new plant cultivars broadens the palette of options available to the industry. Fifteen Swiss chard (Beta vulgaris var. cicla) cultivars were evaluated during the fall/winter of 2014-2015 season (season 1) and 27 cultivars during the fall/winter of 2015-2016 season (season 2) to determine the best performing cultivars for production and landscape use for east Texas and the southeast by assessing survivability and yield. There was an increase in production of 3.0 ± 0.5 g per plant per harvest under the low tunnel. The cultivar …

A Survey Of Non-Crop Plants As Alternative Hosts To Raspberries For Drosophila Suzukii (Spotted Wing Drosophila), Bennur Agbaba

Electronic Theses and Dissertations

The spotted wing fruit fly (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is a pest of small fruit crops. Unlike most other Drosophila species, this insect can oviposit into ripe fruits, rendering them unmarketable. Drosophila suzukii is spreading quickly throughout the continental United States including South Dakota, and causing serious damage to horticultural crops, particularly those within the fruit industry. This study determines the D. suzukii host plant both commercial crops and native plants, and defines non-crop host plants by season in South Dakota. Further, it confirms the occurrence of the fly in southeastern South Dakota and identifies high-risk infestation areas …

Perimeter Cropping As A Means Of Reducing Insect Injury And Increasing Crop Yield, Brett L. Owens

Electronic Theses and Dissertations

The squash vine borer, Melittia cucurbitae Harris, (Lepidoptera: Sesiidae) is a destructive insect known to injure a broad range of cucurbit crops. Many studies have focused on insecticide management of this insect in squash (Cucurbita) and pumpkin (Cucurbita pepo Linnaeus) production; however, little work has been documented on organic approaches to reduce or eliminate injury from this pest to these crops in the Midwest. This study used trap cropping and pollinator mixtures to test whether a reduction of squash vine borer could be achieved in a specific cultivar of pumpkins, Cucurbita pepo ‘Howden’. The study was …

Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher

Electronic Theses and Dissertations

Amelanchier is a genus in the Rosaceae containing shrubs and trees indigenous to North America that possess traits valued by the horticulture industry. Amelanchier spicata (dwarf serviceberry), a heterogeneous complex of hybrids indigenous to eastern North America, has agricultural and ornamental merit with notable characteristics. White blossoms emerge in early spring, edible pomes ripen in the summer, and vibrant, orange foliage occurs in the fall. I investigated phenological and physiological factors influencing adventitious rooting of stem cuttings, the effects of nitrogen source on the development of seedlings grown in container culture, and phenotypic variation among seedlings of A. spicata from …

The Enhancement Of Wild Bees (Hymenoptera: Apoidea) For Pollination Security, Eric M. Venturini

Electronic Theses and Dissertations

The acreage of pollinator-dependent crops continues to expand across the globe. Simultaneously, honey bee hives – an annually rented commodity that growers rely on – are more expensive every year and in some cases, scarce. In response, pollinator-dependent growers seek alternative pollinators. One approach is installing bee pasture on farms, a strategy that enables systems-based farmers to become in-situ farm-scale habitat managers. This thesis first presents a review of the literature on bee pasture plantings and provides a brief overview of some methods for assessing their impacts on the pollinator community. There are three major gaps in current bee pasture …

Water And Nutrient Reuse Within Closed Hydroponic Systems, Emerson Christie

Electronic Theses and Dissertations

Currently, little research exists on the maintenance of individual nutrient balance within the nutrient solutions of closed hydroponic systems and how this maintenance may result in reductions in water and nutrient consumption. In this study, a nutrient solution management procedure was developed to maintain outputs while minimizing inputs. Lactuca sativa (lettuce) crops were grown in six closed hydroponic systems utilizing the nutrient film technique. Electrical conductivity was used as the primary indicator of nutrient solution quality and determined if the nutrient solution was discarded and replaced (control systems) or restored (test systems). Restorations in test systems were made individually to …

Greening The Green Revolution: Moving Beyond Chemicals To Sustainable Agricultural Practices, Elizabeth G. Crawley

Electronic Theses and Dissertations

Agriculture has dominated the economy of many developing countries for centuries, which has led to development policies that center on agricultural development. An obvious approach to improved production is to decrease agricultural losses in the fields and increase efficiency to markets. This study focuses on the developmental role of pesticides and chemical fertilizers on non-traditional agricultural export farming and the adoption of IPM techniques. With farmers in the Comayagua Valley of Honduras, an Asian vegetable production center for the country, as the study population, the costs and benefits of planting oriental vegetables was examined. Statistical analysis was used to examine …

Production Of Heuchera And Coleus, Katherine Fisher Garland

Electronic Theses and Dissertations

According to the USD A ERS, 2008 receipts from greenhouse and nursery sales ranked fourth among agricultural commodities in Maine and seventh in the nation. Greenhouse and nursery plant production relies on the availability of quality water for irrigation and, often involves the use of supplemental lighting to enhance the quality and growth of the plants being produced. Increasing energy costs and more frequent water shortages associated with changing demographics, water use legislation, and climate factors have inspired growers to consider more sustainable approaches to utilizing resources such as water and energy. Precise, crop-specific water and light recommendations are essential …

Reestablishing The Juneberry On The Fort Berthold Indian Reservation: Cultural, Horticultural, And Educational Connections, Kerry E. Hartman

Electronic Theses and Dissertations

Tribal people of the Northern Great Plains have utilized plants for centuries. Amelanchier anifolia (Juneberries/Serviceberries) historically played an important part in the diet and culture of the Mandan, Hidatsa, and Arikara (MHA) Tribal Nations. Research conducted as part of this study into historical and contemporary uses of the Juneberry by MHA Tribal Members indicated extensive historical use and a high interest in Juneberry reestablishment for cultural, nutritional, and economic reasons. Previous research on Juneberries has investigated factors including state of dormancy, propagation method, transplant type, and mulch type. Another purpose of this study was to elucidate the impact of presence …

Revegetating Blackwoods Campground, Acadia National Park: Emphasis On Natural Regeneration Of Red Spruce And Balsam Fir, Cristin O'Brien

Electronic Theses and Dissertations

Blackwoods Campground in Acadia National Park has a declining vegetative understory, characterized by a lack of tree seedling recruitment and shrub populations. This project was embarked upon to identify limiting factors to tree seedling establishment and shrub survival. From these studies, management plans will be developed for revegetating the campground understory. To better understand the factors that inhibit successful seedling establishment, we investigated the effects of varying soil moisture levels on seed germination, seedling survival and seedling dry mass accumulation for red spruce and balsam fir. We also studied the effect of organic layer depth on seedling growth for both …

Woody Plants On The University Of Maine Campus, Lyle Littlefield

Electronic Theses and Dissertations

This investigation centers around the identification and location of the various woody plants on the University of Maine campus. The trees and shrubs having special interest to a horticulturist are given the greater emphasis, but plants other than these have been included so as to make the study useful to any person having an interest in woody plant material. Included in the listing are 425 species and varieties of woody plants, which are represented by 134- genera, and 49 families.

The campus has a good representation of woody plants which would be useful to the trained horticulturist, botanist, forester, or …

A Study Of Mahogany., Roy A. Lawrence

Electronic Theses and Dissertations

No abstract provided.

Woody Plant Materials Suitable For Landscape Planting In Maine, Roger Clapp

Electronic Theses and Dissertations

The aim of this study has been to determine the full range of woody plant materials suitable for landscape planting in Maine. Essentially, the survival of a perennial plant out-of-doors in this State is determined by its hardiness. It is desirable not only to know that a particular plant exists or is hardy at a given place, but also to know over what area the plant may reasonably be expected to be thrifty. This immediately suggests dividing the State into climatic or plant zones. Such a zoning of the State is undertaken in this paper and the plant material is …