Call number: LD2668 .T4 1951 K3 / Master of Science

<p>Nutrient concentrations in plant tissues are directly correlated with the nutritional status and productivity of fruit trees. Plant tissue testing is one of the most effective and accurate methods to determine nutritional status of perennial plants. Tissue test analyses were performed on tart cherry (Prunus cerasus) and peach (Prunus persica) leaves to validate tissue sufficiency levels used in Utah and to determine optimal timing of tissue sampling for prediction of harvest nutrient status, focusing on phosphorus (P), potassium (K), calcium (Ca), iron (Fe), and zinc (Zn). Sufficiency limits that were adopted in Utah were developed in the 1960s from research data accumulated from the primary fruit growing regions in the United States. Limited research has been conducted under Utah growing conditions. Tissue nutrient concentrations over time correlated well with current sufficiency limits and observed nutrient deficiencies in the field. Tissue concentrations of P, K, Fe, and Zn were found to be chronically low in Utah orchards. Plant tissue data demonstrates that mid-season sampling can predict nutrient status at harvest. Mid-season sampling also allows time for corrective adjustments to maintain sufficiency levels and reach optimal fruit production. Nutrient management practices are commonly applied annually to increase yield, fruit quality, and overall health of an orchard. Yield was measured on previously treated tart cherry orchards to determine residual effect on tree nutrient status. Orchards were treated 2 to 3 years prior with rate-response formulations of P and K; one has since adopted recommended fertilizer rates for optimizing tart cherry production in Utah and the other continued with their less aggressive management practices. The less aggressively managed orchard showed trends across treatments, but differences were not significant. Annual fertilizer applications may not immediately show effect during year of application, but long term management is essential for overall productivity of orchards.

<p> African leafy vegetables (ALVs) are a diverse set of crops grown across sub-Saharan Africa. They have been a staple of traditional diets and contain many critical micronutrients but their importance has been largely ignored by researchers and policymakers at the expense of imported crops. Availability, accessibility, and utilization of ALVs are limited by factors across the supply chain. This research investigated seed systems, drought tolerance, hydroponic production, market barriers, consumer preference, and the impact of gender as related to ALVs. We found that ALVs play an important role in food security and that critical differences exist between formal and informal sectors. Women play a stronger role in informal sectors, but the balance between the formal and informal markets is changing, and this may jeopardize the incomes of many women. The determinants of household security were different for male- and female-headed households, and this information can be used to address the gap in food security between genders. Market barriers differed for formal and informal ALV retailers but consumer preference for quality did not, suggesting that investment in postharvest handling may allow ALV growers to capture greater value. We also showed that ALV germplasm is diverse, offering both a wide range of species with different agronomic characteristics and important differences in drought tolerance among accessions. Crop- and location-specific factors impacted farmer adoption of seeds and technologies, highlighting the importance of evaluating policies and interventions with sensitivity to gender, species, and location. ALVs can be used to empower marginalized populations, and this research proposes several ways to do so. However, the market for ALVs is changing rapidly, and future research is needed to monitor trends and assure that these vegetables are used to increase social equality rather than aggravate existing disparities. Promoting savings groups and capital accessibility can help to build this capacity, especially for women. Overall, this research revealed that a wide diversity of under-studied ALV species is contributing to food security in important ways and that the potential exists to strengthen production, distribution chains, and markets further. Well-targeted research and investment could have a substantial impact in this area in improving sustainability and food security for people across sub-Saharan Africa.</p>

<p> Three separate contemporary climate controlled greenhouse rooms in the Sears Plant Growth Facility located at the University of Missouri, Columbia, MO, USA were selected for microclimate analysis. Temperature, relative humidity, and incoming solar radiation data were logged hourly between 5/9/12 and 9/5/12 to test the efficacy of current management practices and to improve understanding of the spatial and temporal climate variability inside the greenhouse rooms. The average horizontal temperature gradient was 0.08 &deg;C&times;m^-1 and the maximum horizontal temperature gradient was 0.83 &ordm;C&times;m^-1. The average vertical temperature gradient was 2.27 &deg;C&times;m^-1 and the maximum lapse rate was 11.65 &deg;C&times;m^-1. Vapor pressure deficit (VPD) calculations were made using data as a proxy to assess plant physiological response to internal conditions. The average horizontal VPD gradient was 0.025 kPam^-1 and the maximum VPD gradient was 0.350 kPa&times;m^-1. Collectively, results indicate a heterogenous distribution of temperature and vapor pressure deficit created primarily by the active cooling system. Several recommendations are supplied to improve the homogeneity of the internal greenhouse climate, which will lead to increased productivity and profits for greenhouse managers.</p>

<p> The grape industry in Oklahoma was valued at $98 million in 2010. In 2015, symptoms resembling Grapevine Leafroll disease were observed, but Grapevine Leafroll-associated Viruses were not detected using enzyme-linked immunosorbent assay (ELISA). A 2-year Cooperative Agricultural Pest Survey was initiated to determine the etiology of the red leaf symptoms in Oklahoma vineyards. In 2016, a total of 121 symptomatic grapevines from 13 counties were sampled and 96 symptomatic grapevines from 14 counties were sampled in 2017. Each sample was tested for Grapevine Red Blotch Virus (GRBV), <i>Xylella fastidiosa </i> (Pierce&rsquo;s Disease), and &lsquo;<i>Candidatus</i> Phytoplasma spp,&rsquo; by polymerase chain reaction (PCR). ELISA was used to test for Grapevine Leafroll associated Virus (GLRaV) strains 1,3 and 4 strains. Rotbrenner, caused by <i>Pseudopezicula traceiphila</i>, (2017 only), can be found in xylem from petioles and the xylem was examined morphologically for signs of fungal structures. In 2016, GRBV was detected in 38% of 121 symptomatic samples, GLRaV-1 and -3 were detected in 16%, GLRaV 4 strains were detected in 2%, and <i>X. fastidiosa</i> was detected in 2%. There were no detections of &lsquo;Ca Phytoplasma spp&rsquo; in 2016 or 2017. In 2017, GRBV was detected in 34% of the 96 samples, GLRaV-1 and -3 were detected in 17%, GLRaV 4 strains were detected in 3%, and <i> X. fastidiosa</i> was detected in 3%. Rotbrenner was not detected in any of the samples in 2017. The findings of this survey provide information to Oklahoma grape growers and extension personnel about the cause of red leaf diseases affecting grapevines so that appropriate management strategies can be implemented in the near future.</p><p>

Digitized by Kansas Correctional Industries

It has been estimated that one-fourth of the fresh fruits harvested are never consumed because of spoilage. This spoilage amounts to many thousands of tons of fruits which are valued annually at several million dollars. Several factors are responsible for the post-harvest spoilage of fruits, namely, pathological, physiological, and mechanical. Men in the past have used various methods to control pathological spoilage of foods. The recent development of nuclear radiation, antibiotics, fungicides, and packaging films provides new methods for prolonging the shelf-life of many fruits. These may prove important in countries like India where refrigeration facilities are not readily available and food shortage has always been a problem. Likewise, in the United States, the present-day marketing of fresh fruits has become more and more complex because centers of consumption are increasingly remote from centers of production. To understand physiological and mechanical spoilage of fruits one should know that perishable products are alive, even though the connection with the source of nourishment has been severed. Continued metabolism and increase in respiration result in over-ripeness, physiological decay, and wilting. The deterioration of fruits by the processes of accelerated respiration induced by ripening, physical changes, and subsequent mechanical damage during transit cannot be stopped; but it can be retarded by lowering the temperature, by treating with respiratory inhibitors, and by careful handling.

Thesis (M.S.)--Ohio State University, 1982. / Includes bibliographical references. Available online via OhioLINK's ETD Center

Thesis (M.S.)--Ohio State University, 1982. / Includes bibliographical references (leaves 78-79). Available online via OhioLINK's ETD Center

The purpose of this study was to explore people-plant interactions and discover the affects of using horticulture therapy techniques with four comprehensive development classroom (CDC) students in four high school horticulture classes. The central research question addressed during the study was, “How do horticulture therapy techniques affect cognitive abilities, emotional behaviors, and social behaviors of CDC students in high school horticulture classes?” The researcher used a total of three different instruments in order to measure various capabilities of each child. These three quantitative instruments utilized during the study consisted of a General Horticulture Knowledge Test, an Emotions Face Test, and the Rosenberg Self-Esteem Scale. The General Horticulture Knowledge Test and the Rosenberg Self-Esteem Scale were each administered to the four student participants a total of three times. The researcher administered these tests before beginning the initial study in February, again in March, and at the conclusion of the study in May. The Emotions Face test was administered before and after horticulture activities were completed. Each of the tests was read aloud by the researcher for better understanding by the participants. Observations also played a key role in this study. Interviews were conducted orally with the two CDC teachers and the four CDC students. The CDC teachers were interviewed twice, once before the study started and once at the conclusion of the study. The four students were interviewed only once, this being at the conclusion of the study. Six teacher aides, who work with the students throughout the day, were also involved in the study. They completed written questionnaires containing the same questions as the CDC teachers were asked in their interviews. This study revealed that the participants had increased levels of self-esteem, positive changes in emotional behaviors, and gains in cognitive behaviors during the four month case study. The tests results combined with interviews and observations of the four student participants, two CDC teachers, and six teacher aides supported the idea that horticulture therapy techniques are beneficial to CDC students enrolled in high school horticulture classes.