Strawberry is an economically important crop in California, with an estimated value of $2.68 billion in 2023. In California strawberry production, mitigation of low plant health and yield often focuses on major soilborne pathogens, while the contribution of minor pathogens and abiotic disorders to production shortcomings are often overlooked. The objectives of the first project in this thesis are to determine the pathogenicity of multiple minor pathogens and quantify other biotic and abiotic factors that can reduce plant health such as viruses and soil salinity. Two pathogens of the black root rot complex, Pythium spp. and Rhizoctonia spp. as well as Neopestalotiopsis rosae are included in this study. The pathogens were identified using ITS DNA sequencing and evaluated for optimal colony growth temperatures. Over the course of two trials, Koch's postulates of P. ultimum and P. irregulare isolates were confirmed for pathogenicity of strawberry roots and crowns, Rhizoctonia spp. isolates were confirmed over 2 trials for pathogenicity of strawberry roots and crowns, and Neopestalotiopsis rosae isolates were confirmed for pathogenicity of strawberry crowns, leaves, and fruit. In 2022 and 2023, 60 root zone soil samples of symptomatic plants that tested negative for major soilborne pathogens were evaluated for electrical conductivity (ECe). Average soil ECe was 1.17 dS/m ranging between 0.18 and 2.45 dS/m, categorizing all samples as non- or slightly-saline except for two which were moderately-saline. Virus testing between 2022 and 2024 diagnosed eight positive samples out of 38 total samples: three in 2022 for Beet pseudo-yellows, two samples in 2023 for Strawberry mild yellow edge and Strawberry polerovirus 1 and one for Strawberry polerovirus 1, and two samples in 2024 for Beet pseudo-yellows. The results from this study suggest that while the tested minor pathogens can infect and reduce strawberry plant health, it is unlikely they are the sole cause of the observed plant mortality from recent diagnostic samples. Additionally, the low to moderate soil salinity levels and infrequent positive virus diagnostics are also not likely the sole cause of observed plant mortality. Future research into these topics could focus on the combination of major and minor pathogens as well as abiotic disorders to decipher how each factor affects plant health. Additionally, Macrophomina phaseolina (MP), an important soilborne pathogen in California strawberry production, was observed to cause 29.7%-52.0% of late-season strawberry mortality in major strawberry growing districts in recent surveys. The objective of the study of this thesis is to assess the efficacy of crop termination and cover cropping on MP suppression to reduce disease incidence of Macrophomina root rot and improve strawberry yield and soil health. Studies were conducted using conventional field soil as a pot trial and a field trial, as well as an organic field trial. The greenhouse pot trial utilized strawberry cultivars Albion and Royal Royce planted in soil collected from a conventional grower field in the Santa Maria district in a randomized complete block design. Treatments included untreated control soil (C), untreated control soil planted with wheat (W) 'Summit 515’ (C+W), soil fumigated with metam potassium (crop termination) planted with wheat (CT+W), and soil fumigated with metam potassium (crop termination) and chloropicrin (flat fumigation) (CT+FF). Plant infection and soil pathogen levels were assessed via plating on semi-selective media and using a pour plate method, respectively. Two repetitions of the trial were conducted. There was no significant soil treatment × cultivar interaction or cultivar effects in trial 1 and 2 for the MP CFU/g soil, but there was a significant soil treatment effect in the MP CFU/g soil of both trials (P = 0.0001). The trial 1 CT+W treatment had the highest-level MP CFU/g soil, which descended in significance to C+W, then C, and then finally CT+FF. In trial 2 CT+W had a significantly higher MP CFU/g soil value than the other treatments, while C and C+W were comparable to each other and both higher than CT+FF. Chemical soil evaluations for mineralizable carbon (MinC) and permanganate oxidizable carbon (POXC) were also performed. Trial 1 C+W had a significantly higher MinC value than CT+FF, while C and CT+W were comparable with both treatments. In the trial 2 MinC soil test the soil treatment × cultivar interaction and the main effects were not statistically significant. In trial 1 and trial 2 POXC soil tests the soil treatment × cultivar interaction and the main effects were not statistically significant. The second year of this study took place in the field and soil samples were collected pre- and post-soil treatments of CT, CT+W, CT+Triticale ‘Pacheco’ (T), CT+W+FF, and CT+T+FF to be evaluated for MP CFU/g soil. T was added as a cover crop treatment to compare a triticale variety to wheat as well as its prevalence as a cover crop in California. There was a significant soil treatment effect (P = 0.02) with post-cover crop wheat treatment having a significantly higher MP CFU/g soil than post-cover crop triticale. The strawberry cultivar Portola was planted after fumigation across all cover crop blocks. Additionally, an organic strawberry field trial compared wheat and triticale cover crops for MP suppression with strawberry cultivars Valiant and Monterey. Soil and plants were tested in the same manner as the pot trial. MP CFU/g soil, MinC, and POXC were not significantly different between soil treatments. Preliminary results suggest single season cover cropping cannot manage high pathogen levels, while crop termination can reduce the pathogen inoculum if the application is timed correctly. The completion of this project will include plant mortality evaluations and microbiome analyses from the field trials. This research aims to help the California strawberry industry by enhancing disease management and reducing fumigant use.

[Truncated abstract] In southern Australian farming systems the replacement of deep-rooted perennial native vegetation with shallow-rooted annual crops and pastures has resulted in rising groundwater tables and an increased incidence of dryland salinity. It has been suggested that to address this issue by restoring hydrological balance, large areas of agricultural land need to be vegetated with perennial plants. One of the most agriculturally productive ways to do this is to introduce perennial pastures, both into upslope groundwater

Indiana University-Purdue University Indianapolis (IUPUI) / Strawberry (Fragaria spp.) is an agricultural crop grown often in temperate regions that has high variability in its susceptibility to freezing injury. To breed cultivars for frost and freezing tolerance, identification of molecular markers associated with low temperature tolerance is advantageous. In this work, I investigated a high-throughput method for protein assays and western blotting. Success in streamlining these processes saves an immense amount of time and allows for the processing of more samples and obtaining larger datasets. Thirty-three octoploid varieties were tested for their accumulation of five different potential biomarkers in response to cold exposure. It was found that total dehydrin content, has the strongest potential to be reliable biomarkers for breeding programs. Previous work identified seven putative dehydrins in Fragaria, where two were purified and positively identified by mass spectrometry and determined to be COR47-like (SKn) and XERO2-like (YnSKn). This work demonstrated that cold tolerance positively correlated with dehydrin protein expression levels. To understand the cold-regulated expression of dehydrins as a function of cold exposure time, the levels of transcripts and corresponding proteins were examined in strongly cold tolerant (Alta) and lesser cold tolerant (FDP817, NCGR1363) Fragaria diploid genotypes. The COR47-like (SKn) and XERO2-like (YnSKn) dehydrins both had higher transcript accumulation and protein levels in the more cold tolerant line in comparison to the two less cold tolerant lines. Lack of correlation between transcript and resulting COR47 protein level in Alta were observed at several different timepoints, where protein accumulation preceded an increase in RNA. This trend was not seen with XERO2. This initiated an investigation to discover at what level COR47 is being regulated. First, the COR47 coding region was sequenced for all the genotypes to confirm against the predicted sequence. In addition, since two isoforms of the COR47 gene exist, and could possibly explain the discrepancy in transcript counts, primers were designed for both isoforms and RT-qPCR was performed to examine the transcripts of COR47 more closely. Through examination of the non-congruence of COR47 transcripts and protein, it was found that transcriptional mechanisms of regulation are not involved, and that post transcriptional and post-RNA splicing mechanisms are likely to be responsible for the observed trend in Alta. Conclusions from this work demonstrate that dehydrin transcripts and dehydrin protein accumulations are strong potential biomarkers for identifying low temperature tolerance in diploid strawberry.

Thesis (MScAgric (Agronomy))--Stellenbosch University, 2008. / The use of hydroponic strawberry production systems is increasing worldwide. Although higher planting densities are possible in vertical production systems, these higher planting densities may have a negative effect on individual plant yield and fruit quality due to lower light levels when compared to conventional (horizontal) production systems. Optimum planting densities will for this reason be affected by light intensities inside the greenhouse and configuration of the vertical production systems. Two experiments were conducted in a plastic cladded greenhouse, fitted with a wetwall and fan cooling system, at the Department of Agronomy, University of Stellenbosch, South Africa during the period of April 2007 to November 2007 (late autumn to early summer). Mean daily maximum temperatures exceeded 26 oC during most of the 14 week harvest period (22 August to 30 November 2007), while photosynthetic active radiation (PAR), measured at 12h00 on cloudless days, inside the greenhouse increased from about 200 μMol m-2 s-1 to about 460 μMol m-2 s-1 during this period. The first experiment compared the effect of two vertical production systems (vertical system and ‘A-shape’ system), subjected to different planting density (16.7, 23.3 and 33.3 plants m-2) and shading (0%, 20%, 50%) treatments, as measured on selected yield, quality and growth factors. The second experiment studied the effect of different planting density (3.3, 5.6 and 10 plants m-2) and shading (0%, 20%, 50%) treatments on the same yield, quality and growth factors in a conventional production system. A comparison with regard to these factors was also made between the highest planting densities of the conventional-, vertical- and ‘A-shape’ system.

The Strawberry Volcanics of Northeast Oregon are a group of geochemically related lavas with a diverse chemical range (basalt to rhyolite) that erupted between 16.2 and 12.5 Ma and co-erupted with the large, (~200,000 km3) Middle Miocene tholeiitic lavas of the Columbia River Basalt Group (CRBG), which erupted near and geographically surround the Strawberry Volcanics. The rhyolitic lavas of the Strawberry Volcanics produced the oldest 40Ar/39Ar ages measured in this study with ages ranging from 16.2 Ma to 14.6 Ma, and have an estimated total erupted volume of 100 km3. The mafic and intermediate lavas of the Strawberry Volcanics include both tholeiitic and calc-alkaline compositions; calc-alkaline andesite is the dominant type by volume. 40Ar/39Ar ages of the mafic and intermediate lava flows range from 15.6 Ma to 12.5 Ma, and volume estimates of the intermediate lavas are approximately 1,100 km3. The magmas that gave rise to the Strawberry Volcanics traveled to the surface through numerous dikes, some of which have been exposed at the surface and supplied lava to fissure – style eruptions and/or shield volcanoes. Herein, we show that the Strawberry Volcanics are related to the CRBG in both time and space and share a chemical affinity, specifically to the Steens Basalt. Chemical similarities are observed in normalized trace element patterns, selected trace element ratios, and radiogenic isotopes. Comparison of the Strawberry Volcanic rhyolites to the other Middle Miocene rhyolites of eastern Oregon associated with the initiation of the Yellowstone – Snake River mantle plume reveals similar eruption ages, trace element compositions, including the rare earth elements (REEs), and "A-type" rhyolite characteristics. These data suggest that the Strawberry Volcanics are part of the regional volcanism (basalt to rhyolite) of the Columbia River Basalt Province. The petrogenesis of the Strawberry Volcanics can be explained as follows: 1) The tholeiitic, intermediate magmas were produced by fractional crystallization of mafic magmas, which have a commonality with the surrounding Columbia River Basalt Group; 2) The calc-alkaline magmas are a result of mixing between tholeiitic basalt, rhyolite, and crust. The arc-like signature of the calc-alkaline lavas (elevated large ion lithophiles) is a result of both the melting source region and the end-members with which the mafic magmas mixed/contaminated. Other authors have produced similar findings from within the Basin and Range/Oregon-Idaho graben and CRB province. The difference at the Strawberry Volcanics is that there is no need for a primitive calc-alkaline magma or extensive fractional crystallization to generate the calc-alkaline andesites. Alternatively, the calc-alkaline magmas of the Strawberry Volcanics were generated by a more primitive tholeiitic magma than erupted at the surface, which interacted with crustal melts and assimilated crustal lithologies from the complex zone of assimilated terranes that make up the basement of eastern Oregon.

O método de extração QuEChERS, foi ajustado, validado e utilizado para a determinação de doze agrotóxicos organoclorados em 37 amostras de quinoa provenientes da colheita 2010-2011 de Puno - Peru e 36 amostras de morango provenientes de três varejões da cidade de Piracicaba do Estado de São Paulo - Brasil coletadas durante o período de outubro de 2010 até setembro de 2011, usouse um sistema cromatográfico a gás acoplado a um detector de captura de elétrons μECD. Por outro lado para a determinação de 36 agrotóxicos nas amostras morango e 42 agrotóxicos em quinoa, o QuEChERS foi ajustado e validado para seu uso com um sistema cromatográfico líquido acoplado a espectrometria de massas LCMS/ MS; para o processo de validação usou-se amostras de quinoa e morango sem resíduos de agrotóxicos, os quais foram usados como branco de matriz. Os métodos mostraram linearidade de r2 >= 0,99; LQs na ordem de 0,001 mg kg-1, foram realizados testes de recuperações considerando os LQs e dez vezes estes, sendo que as recuperações foram entre 70% e 120% na maioria das concentrações. Com o intuito de avaliar o efeito do tamanho de partículas de quinoa no processo de validação do método QuEChERS para a determinação de sete agrotóxicos com uso de CG-μECD, foram realizados três tipos de moagem usando processador de alimentos e um sistema de moagem criogênico, observou-se uma maior uniformidade das partículas e um incremento do efeito matriz nas amostras tratadas com sistema criogênico. Das 37 amostras de quinoa analisada uma amostra (Cabanillas) proveniente do sistema de produção orgânico (Salcedo INIA) mostrou contaminação por quatro agrotóxicos (OP DDE com 0,015 mg kg-1, PP DDE 0,032 mg kg-1, PP DDD 0,089 mg kg-1 e endosulfan sulfato com 0,034 mg kg-1) e das 36 amostras de morango seis apresentam contaminação por endosulfan sulfato nas concentrações de 0,003 a 0,020 mg kg-1 e uma amostra coletada no dia 15/04/2011 apresentou 0,011 mg kg-1 de procloraz, compostos que não são permitidos para serem usados em morango. Conclui-se que o método QuEChERS usado com o sistema CG-μECD e LC-MS/MS é uma alternativa viável para a determinação de agrotóxicos em morango e quinoa. / The QuEChERS extraction method has been adjusted, validated and used for determination of twelve organochlorine pesticides on 37 quinoa samples from the harvested 2010-2011 from Puno - Perú and 36 strawberries samples from three markets from Piracicaba city in Sao Paulo State-Brazil collected during the period from October of 2010 to September of 2011, were used a gas chromatographic system coupled to an electron capture detector μECD. On the other hand, for the determination of 36 pesticides in strawberries samples and 42 quinoa samples, The QuEChERS method was adjusted and validated for use with a liquid chromatographic system coupled to mass spectrometer LC-MS/MS; for the validation process a quinoa and strawberries samples without pesticides residues, which were used as a blank. The methods were linear r2 >= 0.99; LQs in the order of 0.001 mg kg- 1, were carried out recoveries considering the LQs and ten times these, and the recoveries were between 70% and 120% in most of the concentrations. In order to evaluated the effect of the particle size of the quinoa on the validation process of the QuEChERS method for determination of seven pesticides using GC-μECD, were performed three types of milling using a food processor and cryogenic grinding, there were a greater uniformity of the particles and increase of the matrix effect in the samples treated with cryogenic system. From the 37 quinoa samples analyzed one sample (Cabanillas) coming from organic system production (Salcedo INIA) showed contamination by four pesticides (OP DDE with 0.015 mg kg-1; PP DDE 0.032 mg kg- 1; PP-DDD 0.089 mg kg-1 and endosulfan sulfate with 0.034 mg kg-1) and from the 36 strawberries samples six showed contamination by endosulfan sulfate in the concentrations of 0.003 to 0.020 mg kg-1 and one sample collected 15/04/2011 showed 0.011 mg kg-1 of prochloraz, compounds that are not permitted to be used in strawberries. We concluded that the QuEChERS method used with a system of GC- μECD and LC-MS/MS is a viable alternative to determinate pesticides in strawberries and quinoa.

Submitted by (ana.araujo@ufrpe.br) on 2017-02-17T14:14:19Z No. of bitstreams: 1 Jose Machado Coelho Junior.pdf: 1596177 bytes, checksum: e2b2b69a4eb6a4394ff0b610d87af29b (MD5) / Made available in DSpace on 2017-02-17T14:14:19Z (GMT). No. of bitstreams: 1 Jose Machado Coelho Junior.pdf: 1596177 bytes, checksum: e2b2b69a4eb6a4394ff0b610d87af29b (MD5) Previous issue date: 2009-05-22 / For the cultivation of strawberries need a good planning of the planting, because the crop is susceptible to diseases and as part of the diet, one should minimize the large amount of pesticides that get to fight them. In search of the culture conditions edafoclimáticas it was necessary to open new frontiers in the tropical regions as Mesorregião da Mata de Pernambuco. This study aimed to analyze the characters of 11 cultivars of strawberry in the tropical conditions of Mesorregião da Mata. The cultivation was carried out in region of high temperatures was evaluated in greenhouse where the plant morphology, physico-chemical and topographical pseudofruit of the median leaves of cultivars. The experimental design was completely randomized, with five replications, each pot a plot. Cultivars Camino Real, Diamond, Sweet Charlie and windows were the only ones that showed production of strawberries. The Ventana cultivar showed high concentration of ascorbic acid. Cultivars Dover, Oso Grande and Tudla made the most important leaf plan. The cultivar Sweet Charlie made more rugged topography. / Para o cultivo do morangueiro é necessário um bom planejamento do plantio, devido a cultura ser suscetível a doenças e por fazer parte da dieta alimentar, devendo-se minimizar a grande quantidade de agrotóxicos que recebe para combatê-las. Em busca de condições edafoclimáticas à cultura fez-se necessário abrir novas fronteiras em regiões de clima tropical como a Mesorregião da Mata de Pernambuco. Este trabalho teve como objetivo analisar os caracteres de 11 cultivares de morangueiro nas condições tropicais da Mesorregião da Mata Pernambucana. O cultivo foi realizado em região de temperaturas elevadas em telado onde se avaliou caracteres morfológicos da planta, físico-químicos dos pseudofrutos e topográficos dos folíolos medianos das cultivares. O delineamento experimental utilizado foi o inteiramente casualizado com cinco repetições, sendo cada vaso uma parcela. As cultivares Camino Real, Diamante, Sweet Charlie e Ventana foram as únicas que apresentaram produção de morangos. A cultivar Ventana apresentou concentração elevada de ácido ascórbico. As cultivares Dover, Oso Grande e Tudla apresentaram o relevo foliar mais plano. A cultivar Sweet Charlie apresentou relevo mais acidentado.

In this research project, real natural strawberries bought from different local sources were profiled by gas chromatography-mass spectroscopy (GCMS). These profiles were then used as a reference to compare GCMS profiles of commercial artificial strawberry flavor products such as strawberry flavored Cool Splashers™, Gatorade®, and Aquacal® flavored water. The chromatograms obtained were patterned using simple visual observations, scatter plot designs, Mann-Whitney U Test, and correlation coefficients. The artificially flavored commercial products tend to have simpler chromatograms. The Burger King® milkshake, Gatorade®, and Hi-C® are the most similar to that of the natural strawberry flavor. Their correlation coefficients are 0.972, 0.870, and 0.984 respectively. The Mann-Whitney U Test results also support the conclusions from correlation coefficients. However, the natural products tend to have more constituents including the main flavoring compounds. Thus fresh produce have better flavor and are more nutritious for a good reason.

Soil salinity, a yield-limiting condition, has plagued crop production for centuries by reducing crop productivity. Research has introduced methods for successfully managing soil salinity. This research discusses the adaptation of established management methods to create new soil salinity management techniques. One adapted technique is an automated crop screening apparatus. A new design was created and successfully used in rapidly screening two strawberry cultivars to determine their tolerance to salinity. Screening crops and determining their tolerance to yield-limiting conditions are essential in managing soil salinity. Another salinity management tool used in this research was electromagnetic induction (EMI). EMI was used to complete a basin-scale inventory over an 18,000 ha study area in Cache County, Utah. The data obtained during the inventory were used to create EMI calibration models and a basin-scale map showing the spatial distribution of apparent soil electrical conductivity (ECa). These new methods for crop tolerance screenings and basin-scale salinity inventories will assist in successfully managing soil salinity and decrease its effect on the global food supply.

Stream restoration has become a popular management tool for attempting to increase and/or restore fish populations by improving habitat. A section of the Strawberry River, Utah recently underwent a stream restoration project, where the main goals of the project included increasing spawning activity, rearing potential, and resident populations of Bear Lake cutthroat trout Oncorhynchus clarkia utah. The impact of the restoration project on cutthroat trout was investigated by first characterizing preferred habitat for different life stages, investigating habitat as a limiting factor in the system, and then assessing the quality of available habitat by comparing restored/unrestored sections of stream and pre-restoration/post-restoration of the same sections of stream. Results indicated cutthroat trout in the Strawberry River preferred faster water velocities, shallower depths, moderate substrates sizes, and riffle habitat types for spawning. In contrast, juvenile and adult life stages preferred deeper sections of stream, the presence of cover, and pool habitat types. Limiting factor analyses suggested spawner abundance may be limiting in the Strawberry River and maximum daily temperatures during the summer may be the strongest limiting habitat factor for juvenile and resident adult cutthroat trout. Restoration generally appeared to initiate a shift towards more favorable habitat, especially in terms of increasing near-bed velocity and increasing the proportion of preferred substrate sizes for spawning, and increasing the percentage of pools for juvenile and resident adult life stages. The potential benefits of the restoration remained somewhat ambiguous, a result of relatively small differences observed between study reaches, limited pre-restoration data, high spatial and inter-annual variability within and among control study reaches, and the inherently delayed reaction of ecological responses to physical changes from restoration. However, these issues can be resolved through continued monitoring. Long-term monitoring would allow for the accounting of natural variability to further tease out differences resulting from restoration and differences resulting from natural fluctuations. Additional monitoring would also capture long-term responses, which has the potential to be significant considering the relatively slow response of riparian vegetation to restoration. This study also provides a baseline dataset and template for future long-term monitoring efforts.