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Effects of Bacillus Mycoides Supplement in a Reduced Frequency Fungicide Program on Chambourcin Grapevines (Vitis Vinifera L.)Mairs, Ryan Alan 01 July 2018 (has links)
Fungal diseases pose significant challenges for grapevine producers in Kentucky due to the region’s abundant moisture and relative humidity. Methods to reduce fungicide application frequency would prove both economically and temporally valuable to producers. A field experiment was established in Bowling Green, KY in 2017 to investigate Bacillus mycoides isolate J (LifeGard) as a supplement to a fungicide program for systemic acquired resistance (SAR). Three fungicide treatment regimens were implemented consisting of a program modelled from the Midwest Fruit Pest Management Guide (2017) and an identical program supplemented with 140 g ha-1 LifeGard per application (both applied on 14 day intervals), a reduced frequency application every 28 days supplemented with 140 g ha-1 LifeGard, and an untreated control. Treatments were applied to 9-year-old French-Hybrid grapevines (cv. Chambourcin); each treatment was replicated 3 times in a randomized complete block design. All treatments were applied with a backpack sprayer delivering 150 L ha-1 at 2 Bar pressure. Canopy management, fertility, herbicide, and insect management were standardized across treatments and no supplemental irrigation was applied. Data collected included fruit yield, pH, ºBrix, and titratable acidity (TA). Data were analyzed with SAS PROC GLIMMIX; differences in means were determined at < 0.05. Plots supplemented with B. mycoides had lower fruit pH than untreated plots but higher fruit pH than the traditional fungicide program. Treatment regime did not influence Brix, TA, or total yield; however, all treated plots yielded more high quality fruit than the untreated control.
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IMPACT OF A HIGH OIL AND PROTEIN ON AGRONOMIC TRAITS AND OVERALL SEED COMPOSITION IN SOYBEANAL-Amery, Maythem 01 January 2017 (has links)
New soybean lines have been developed with significantly higher oil, protein + oil and higher meal protein. These soybeans contain a VgD1 gene (highly active acyl-CoA:diacylglycerol acyltransferase, DGAT from Vernonia galamensis (VgDGAT1A) produces much higher oil synthesis and accumulation activity in soybean. Soybean with active DGAT from Vernonia galamensis (VgDGAT1A) has active TAG biosynthesis relative to other DGATs including from soybeans and Arabidopsis. DGATs catalyze the final step of TAG synthesis: DAG (diacylglycerol) + acyl-CoA → TAG + CoASH (Coenzyme A is notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle). A thorough analysis of the major components in VgD1 lines, especially those of nutritional or anti-nutritional value including what else changed (decreased); and what remained at normal levels was conducted. A field study was conducted in Spindletop and Princeton KY, reviled no reduction in yield nor protein, and about 4 % (DW) more oil was obtained in Princeton and 2% (DW) in Spindeltop. No consistent reduction in the other seed composition.VgDGAT1A soybean lines indicated noticeably early maturation compared to the parental line. This is associated with higher expression of the flowering genes FT2 (FLOWERING LOCUS T2) and FT5 (FLOWERING LOCUS T5), for the high oil lines. A single recessive mutation in soybean (MIPS) myo-inositol 1-phosphate synthase, confers a seed phenotype of increase inorganic phosphate (Pi) crossed with high oil lines expressing a DGAT from Vernonia galamensis (VgDGAT1A) (VgD). The oil and protein were maintained compart to VgD. VgD X MIPS (VM), had 21.2, and 22 % oil in 2015, and 23.3 and 24.0 oil in 2016, and protein 46, 49 in 2015, and 37 and 39 % in 2016. Phosphate results suggesting the cross MV is still segregating for MIPS and more selection and planting are needed.
Measurement of seed phosphate levels is an established technique for screening for low phytate mutants but to date, it has not been performed non-destructively from single soybean seeds. A protocol was developed greatly reducing the sample size thereby reducing the cost and time and saving a generation in the selection of low phytate mutant seeds based on the high Pi phenotype.
Genotyping single seeds are useful in breeding and genetics while maintaining high germination rates. Nondestructive single-seed genomic DNA extraction protocols using 12 mg cotyledon tissue with a modified cetyl trimethyl ammonium bromide (CTAB) technique and a commercial seed DNA extraction kit using 1 mg cotyledon tissue were developed for dry soybean seeds and cross-verified with leaf DNA analysis.
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CHEMICAL TOPPING BURLEY TOBACCORichmond, Mitchell D. 01 January 2018 (has links)
The act of topping tobacco (Nicotiana tabacum L.) involves the removal of the terminal bud or inflorescence of the tobacco plant. This practice ordinarily is accomplished by manually removing the top of each tobacco plant in an entire field which is labor intensive and costly. Chemical topping utilizes sucker control products to inhibit the terminal bud and axillary bud growth without manually removing the top of the tobacco plant. There were several research objectives in order to determine the utility of a chemical topping system: 1) determine if burley tobacco could be chemically topped with currently registered suckercide products while maintaining control of subsequent sucker growth; 2) compare chemical topping to manual topping for yield and leaf quality; 3) identify burley tobacco varieties that are better suited for chemical topping systems; 4) determine the optimum plant growth stage at which chemical topping treatments should be applied; and 5) identify genes that are differentially expressed following suckercide applications. To pursue our objectives, studies were initiated investigating the optimum timing of application, ideal variety maturity, and efficacy of suckercide applications using combinations of maleic hydrazide (MH), butralin, and fatty alcohols (FA). The terminal bud was not well controlled with FA or butralin alone nor was acceptable sucker control or total yield achieved. Our data suggest that chemically topping burley tobacco with a tank mixture of MH and a local systemic may be a suitable alternative to manual topping, as total yield and leaf quality grade index were not significantly different and total TSNA and MH residues were not significantly higher compared to manual topping. The 10% button and 50% button application timings were best suited for chemical topping practices. Treatments that targeted the 10% bloom stage did not completely halt flower development, but all application timings resulted in excellent sucker control. Medium and late maturity burley varieties were found to be suitable for chemical topping methods; however, timing the suckercide application may be less difficult in later maturing varieties. Chemically topping burley tobacco at 10 to 50% button stages with a tank mixture of MH and a local systemic suckercide was found to be a suitable alternative to manual topping, and would potentially result in labor savings for burley tobacco growers. Expression of genes related to phytohormones, meristem development, cell division, DNA repair and recombination were affected following MH treatment, which likely leads to the inhibition of apical and axillary meristem development.
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ENHANCED EFFICIENCY NITROGEN FORMULATION EFFECT ON GRASS-LEGUME PASTURE PRODUCTIVITYPayne, Kathryn Marie 01 January 2019 (has links)
The use of nitrogen (N) fertilizer is generally restricted on mixed species forage systems due to its stimulatory effect on grasses which increases competition with legume species. Reduced legume growth from this competition can compromise forage nutritive value and prospective yields. The controlled-release nature of several enhanced efficiency fertilizer N products holds the potential to improve legume persistence in mixed species pastures while providing supplemental N required by the grass component. The studies contained in this dissertation evaluated the effect of different enhanced efficiency N formulations (ATU, ESN, methylene urea, SuperU, and a 75% ESN: 25% urea blend) and untreated urea on yield, nutritive value, and legume persistence in a ‘Wrangler’ bermudagrass and ‘Durana’ white clover mixture (2014-2016 growing seasons), ‘KY-31’tall fescue and ‘Kenland’ red clover mixture (2015-2016 growing seasons), and ‘KY-31’ stockpiled tall fescue (2015-2017). The three studies were conducted at the University of Kentucky Spindletop Research Farm in Lexington, KY in a randomized complete block design. In the bermudagrass-white clover study, all enhanced efficiency N sources maintained white clover populations similar to the unfertilized grass/clover control, but only ESN caused greater clover composition than standard urea. Total forage yields increased linearly with N rate in all years, but dry weather conditions in the second and third years resulted in lower total yield. Forage nutritive value followed general trends throughout each growing season, but ESN’s ability to maintain clover resulted in higher nutritive value. In the tall fescue-red clover, total forage yields curvilinearly increased with N rate in 2015 but did not vary in 2016. ESN and ESN+urea blend treatments retained clover composition similar to that of the unfertilized control. Stockpiled forage yield increased with higher N rates. Enhanced efficiency N fertilizers with the ability to control N release can enhance forage yield while maintaining clover in mixed species swards.
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Impact of a Winter Rye Cover Crop on Edge-of-Field Nutrient Losses and Corn Silage ProductionGriffith, Keegan 01 January 2019 (has links)
Cover crops have the potential to reduce environmental impacts of corn production. The objective of this study was to quantify differences in nitrogen (N) and phosphorus (P) loading between corn plots with or without a winter rye cover crop (Secale cerale). Four field plots (30 x 46 m) in Chazy, NY with edge-of-field monitoring were used for the study. Two plots were randomly assigned a rye cover crop treatment and planted with a grain drill at a rate of 112 kg ha-1 after corn silage harvest in 2015 and 2016. Continuous water flows were monitored from surface runoff and tile drain hydrologic pathways dur-ing runoff events. Soluble reactive P (SRP), total P (TP), nitrate-N, total N (TN), and to-tal suspended solids (TSS) concentrations were measured and multiplied by runoff vol-umes to estimate nutrient export. Surface runoff from rye plots had lower nutrient loss compared to control plots. Cumulative nitrate-N exports were similar between treatments (15.7 vs. 14.8 kg nitrate-N ha-1 for rye and control, respectively). Cumulative TN exports were numerically higher for control plots compared to rye plots, (18.8 vs. 21.4 kg TN ha-1). Cumulative TP and SRP exports (surface + tile) for rye were 2.2 and 3-fold greater than control plots, (0.51 vs. 1.19 kg TP ha-1 and 0.33 vs. 0.96 kg SRP ha-1). Total P and SRP loads in surface runoff were 3.0-fold greater for control plots compared to rye plots (0.36 vs. 1.12 kg TP ha-1 and 0.32 vs. 0.94 kg SRP ha-1). TSS load in surface runoff was numerically higher for control plots compared to rye (5.7 vs. 20.6 kg ha-1). Cumulative surface runoff was 1.8-fold greater in control plots compared to rye plots (112.6 mm vs. 207.7 mm), while cumulative tile runoff was numerically higher in rye plots compared to control (83.2 mm vs. 66.1mm). Snowmelt events contributed the majority of phosphorus losses (96% of SRP and 92% of TP), emphasizing the need to implement management techniques that reduce P transport risk during the non-growing season. Winter rye re-duced snowmelt TP export by 3-fold compared to the control plots (0.33 kg TP ha-1 and 1.03 kg TP ha-1). The winter rye cover crop planted after corn silage harvest effectively reduced erosion and P transport in surface water runoff compared to corn silage left fal-low after harvest. In addition to significantly reducing P exports, farms have the option of harvesting rye as a forage crop and double cropping with corn. In this way, more total forage is possible for the farm in addition to offering environmental conservation and wa-ter quality benefits.
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A Simple Metabolic Switch May Activate Apomixis in <i>Arabidopsis thaliana</i>Sherwood, David Alan 01 December 2018 (has links)
Apomixis, asexual or clonal seed production in plants, can decrease the cost of producing hybrid seed and enable currently open pollinated crops to be converted to more vigorous and higher yielding hybrids that can reproduce themselves through their own seed. Sexual reproduction may be triggered by a programmed stress signaling event that occurs in both the meiocyte, just prior to meiosis, and later in the egg just prior to embryo sac maturation. The prevention of stress signaling and the activation of a pro-growth signal prior to meiosis triggered apomeiosis, the first half of apomixis. The same approach was used prior to embryo sac maturation to trigger parthenogenesis, the second half of apomixis. This discovery suggests that apomixis exists as a program that can be activated by the appropriate metabolic signal at the appropriate developmental stages. Therefore, apomixis may be alternative mode of reproduction rather a ‘broken’ form of sexual reproduction.
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Inheritance of Resistance to Loose Smut (U. tritici) in Certain Wheat CrossesTolman, Bion 01 May 1933 (has links)
During recent years the principles of Mendelism have been used extensively in the production of the new types of plants possessing resistance to various diseases. Results of this mode of attacking the disease problem have been very favorable. Old varieties are gradually giving way to newer types equal to or exceeding in quality and productivity as well as possessing resistance to one or more diseases.
Loose smut (U. tritici) in wheat, while not as serious a problem in Utah as the covered smut (T. tritici), according to Tapke (14) has caused an average annual loss of between 50,000 and 100,000 bushels of wheat. these data shown in figure 1 are for the period 1917 to 1926, inclusive.
The various methods advocated for the control of loose smut (U. tritici), with the exception of the use of resistant varieties and hot water treatments, either have been impradtical of application or have been ineffective in control or both (14).
The modified hot water treatment of Freeman and Johnson (4), has generally been the method recommended. While this method is effective if properly executed, it is rather complicated and tedious to apply, especially for farmers who are not usually properly equipped. Because of this and the fact that the disease frequently escapes observation, seed treatment for the control of loose smut (U. tritici) is seldom practiced; as a result the smut is allowed to go unchecked. The development of a resistant variety possessing the adaptability and desirable characteristics of our locally-grown spring wheats would be a decided advantage to the farmers in combating the disease.
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Seedling Establishment of Alfalfa Comparing Four Varieties, Three Fungicides and Two InoculumsFoster, Ronald Brown 01 May 1955 (has links)
The establishment of alfalfa is expensive and good initial stands permit the farmer to secure high yields and spread establishment costs over several years, Of the factors involved: seedbed preparation, fertilization, seed viability, method of planting, and water application are controlled by the farmer, On the other hand, beneficial and detrimental microflora are not so easily controlled because practices aimed at controlling the detrimental microflora may also destroy the beneficial.
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Inheritance of Glume and Kernel Color, of Awnedness, and of Spike Density in a Cross Between Ridit and Sevier WheatNelson, Leslie W. 01 May 1931 (has links)
This paper is devoted principally to the presentation and discussion of the results obtained when certain contrasting characters were brought together in a wheat cross between Ridit and Sevier 59. this is one of the crosses made in an attempt to develop a wheat adapted to this region with the following desirable qualities: Bunt resistance, strong straw, hard kernels, and heavy yield. How near this ideal is approached in succeeding generations can be told only by extensive tests. The genetic study herein presented was made to hasten the time when some of the progeny of this cross may become of economic value.
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Fertilizer Studies as Conducted on the Carbon County Experimental Farm with Special Reference to Treble-SuperphosphateZobell, Delos 01 May 1932 (has links)
In 1927 an experimental farm was established in Carbon County, Utah. The farm is on a new irrigation tract south of the Price River and about four miles south of Price. The agricultural problems of the Carbon County Experimental Farm and the locality which it serves are distinctly different from those of most of the farming sections in Utah. The soil of this region is of a sandy, silty nature apparently with deflocculated colloids which make it somewhat difficult to manage. There is a low percentage of organic matter in this soil, and because of this and its impervious condition the soil absorbs water slowly. The range in moisture content at which the soil may be tilled is rather narrow.
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