Plant Sciences Commons^™

Adjustment And Optimization Of The Cropping Systems Under Water Constraint, Pingli An, Wei Ren, Xiliin Liu, Mengmei Song, Xuemin Li

Plant and Soil Sciences Faculty Publications

The water constraint on agricultural production receives growing concern with the increasingly sharp contradiction between demand and supply of water resources. How to mitigate and adapt to potential water constraint is one of the key issues for ensuring food security and achieving sustainable agriculture in the context of climate change. It has been suggested that adjustment and optimization of cropping systems could be an effective measure to improve water management and ensure food security. However, a knowledge gap still exists in how to quantify potential water constraint and how to select appropriate cropping systems. Here, we proposed a concept of …

Apple Tree Responses To Deficit Irrigation Combined With Periodic Applications Of Particle Film Or Abscisic Acid, Khalid M. Al-Absi, Douglas D. Archbold

Horticulture Faculty Publications

The objective of this study was to determine if the application of two antitranspirant compounds would moderate water deficit stress effects on physiological responses of “Granny Smith”, “Royal Gala” and “Golden Delicious” apple (Malus domestica Borkh.) trees on MM106 rootstock that occur during deficit irrigation. Uniform trees were grown in pots under water supply regimes of 30%, 60%, and 80% depletion of available water (DAW) before irrigation to runoff and received applications of kaolin particle film (PF) or abscisic acid (ABA) at 0, 30 and 60 days. At 120 days, genotype and deficit irrigation affected nearly all leaf traits, …

High-Input Management Systems Effect On Soybean Seed Yield, Yield Components, And Economic Break-Even Probabilities, John M. Orlowski, Bryson J. Haverkamp, Randall G. Laurenz, David A. Marburger, Eric W. Wilson, Shaun N. Casteel, Shawn P. Conley, Seth L. Naeve, Emerson D. Nafziger, Kraig L. Roozeboom, William J. Ross, Kurt D. Thelen, Chad Lee

Plant and Soil Sciences Faculty Publications

Elevated soybean [Glycine max (L.) Merr.] prices have spurred interest in maximizing soybean seed yield and has led growers to increase the number of inputs in their production systems. However, little information exists about the effects of high-input management on soybean yield and profitability. The purpose of this study was to investigate the effects of individual inputs, as well as combinations of inputs marketed to protect or increase soybean seed yield, yield components, and economic break-even probabilities. Studies were established in nine states and three soybean growing regions (North, Central, and South) between 2012 and 2014. In each site-year …

Expression Of A Constitutively Active Nitrate Reductase Variant In Tobacco Reduces Tobacco-Specific Nitrosamine Accumulation In Cured Leaves And Cigarette Smoke, Jianli Lu, Leichen Zhang, Ramsey S. Lewis, Lucien Bovet, Simon Goepfert, Anne M. Jack, James D. Crutchfield, Huihua Ji, Ralph E. Dewey

Kentucky Tobacco Research and Development Center Faculty Publications

Burley tobaccos (Nicotiana tabacum) display a nitrogen-use-deficiency phenotype that is associated with the accumulation of high levels of nitrate within the leaf, a trait correlated with production of a class of compounds referred to as tobacco-specific nitrosamines (TSNAs). Two TSNA species, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN), have been shown to be strong carcinogens in numerous animal studies. We investigated the potential of molecular genetic strategies to lower nitrate levels in burley tobaccos by overexpressing genes encoding key enzymes of the nitrogen-assimilation pathway. Of the various constructs tested, only the expression of a constitutively active nitrate reductase (NR) …

Genetic Engineering And Sustainable Crop Disease Management: Opportunities For Case-By-Case Decision-Making, Paul Vincelli

Plant Pathology Faculty Publications

Genetic engineering (GE) offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several …

Aphid Performance Changes With Plant Defense Mediated By Cucumber Mosaic Virus Titer, Xiaobin Shi, Yang Gao, Shuo Yan, Xin Tang, Xuguo Zhou, Deyong Zhang, Yong Liu

Entomology Faculty Publications

Background: Cucumber mosaic virus (CMV) causes appreciable losses in vegetables, ornamentals and agricultural crops. The green peach aphid, Myzus persicae Sulzer (Aphididae) is one of the most efficient vectors for CMV. The transmission ecology of aphid-vectored CMV has been well investigated. However, the detailed description of the dynamic change in the plant-CMV-aphid interaction associated with plant defense and virus epidemics is not well known.

Results: In this report, we investigated the relationship of virus titer with plant defense of salicylic acid (SA) and jasmonic acid (JA) during the different infection time and their interaction with aphids in CMV-infected tobacco plants. …

Characterizing Genotype X Management Interactions On Soybean Seed Yield, David A. Marburger, Bryson J. Haverkamp, Randall G. Laurenz, John M. Orlowski, Eric W. Wilson, Shaun N. Casteel, Chad D. Lee, Seth L. Naeve, Emerson D. Nafziger, Kraig L. Roozeboom, William J. Ross, Kurt D. Thelen, Shawn P. Conley

Plant and Soil Sciences Faculty Publications

Increased soybean [Glycine max (L.) Merr.] commodity prices in recent years have generated interest in high-input systems to increase yield. The objective of this study was to evaluate the effects of current, high-yielding cultivars under high- and low-input systems on soybean yield and yield components. Research trials were conducted at 19 locations spanning nine states from 2012 to 2014. At each location, six high-yielding cultivars were grown under three input systems: (i) standard practice (SP, current recommended practices), (ii) high-input treatment consisting of a seed treatment fungicide, insecticide, nematistat, inoculant, and lipo-chitooligosaccharide (LCO); soil-applied N fertilizer; foliar LCO, fertilizer, …

Correlating Bulk Density (With Dockage) And Test Weight (Without Dockage) For Wheat Samples, Rumela Bhadra, Mark E. Casada, Josephine M. Boac, Aaron P. Turner, Sidney A. Thompson, Michael D. Montross, Ronaldo G. Maghirang, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

In grain bins, the compaction of stored grain is caused by the overbearing pressure of the bulk material in the bin. To predict the amount of grain in the bin, compaction values must be determined based on the average bulk density (BD) of the stored material. However, BD is determined following the Federal Grain Inspection Service (FGIS) guidelines for measuring test weight (TW), which require that dockage be removed prior to measuring wheat TW. Thus, this creates a problem for predicting grain compaction and conducting inventory studies, because the average BD of the grain in a bin for these calculations …

Probing The Plant Cell Wall With Herbicides: A Chemical Genetics Approach, Chad B. Brabham

Theses and Dissertations--Plant and Soil Sciences

The primary cell wall is a highly organized multi-layered matrix of polysaccharides (cellulose, hemi-cellulose, and pectin). The ability of the rigid cell wall to sufficiently loosen to allow growth is a complex process that differs considerably between grasses monocots and dicots. Cellulose is the major structural component required for anisotropic cell expansion and is synthesized by CELLULOSE SYNTHASE A (CesA) proteins. Here, our objectives were two-fold: 1) dissect cell walls and cellulose biosynthesis in dicots and grasses using chemical biology and reverse genetic approaches 2) characterize and classify the inhibitory mechanisms of cellulose biosynthesis inhibitors (CBIs). A reverse genetics TILLING …

Irrigated Zea Mays Response To Nitrogen And High Plant Population Density In Narrow Rows, Julie Baniszewski

Theses and Dissertations--Plant and Soil Sciences

Modern genetics have improved maize hybrids to better tolerate stress, use nutrients more efficiently and potentially yield higher. Management practices, such as narrow row technology and high plant population density (PPD) may further improve yields in modern maize under irrigated, non-limiting conditions. High PPD (74, 99, 124, 148 K seeds ha^-1) were tested in narrow rows with up to four nitrogen (N) rates in three locations over two years in Kentucky with a modern maize hybrid in irrigated, non-limiting conditions. Results indicate that optimal seeding rates were 99,000 to 124,000 seeds ha^-1, providing maximum yield and …

Optimization Of Doubled Haploid Production In Burley Tobacco (Nicotiana Tabacum L.), Ezequiel De Oliveira

Theses and Dissertations--Plant and Soil Sciences

Doubled haploidy (DH) is a plant breeding technique that is often utilized by plant breeders to minimize the time required to reach homozygosity in breeding lines. The first objective of this study was to compare two methods of generating DH lines in tobacco (Nicotiana tabacum L.). Inbred burley tobacco varieties TN 90LC and GR 149LC were used to produce both androgenic derived doubled haploids (ADDH) and maternally derived doubled haploids (MDDH). The relative agronomic performance of TN 90LC and GR 149 LC ADDH and MDDH lines was compared when used either as pure-line cultivars or when used for the …

Field Evaluation Of Burley Lines Containing Alleles Minimizing Nicotine To Nornicotine Conversion, Cameron G. Shelton

Theses and Dissertations--Plant and Soil Sciences

CYP82e4, CYP82e5, and CYP82e10 mutant alleles that minimize the conversion of nicotine to nornicotine have been introgressed into numerous existing low converting (LC) burley varieties and parental lines developed by the Kentucky-Tennessee tobacco breeding program. A backcross breeding protocol was utilized, with the objective being the creation of "e3" varieties that differed from their LC counterparts only for nornicotine and nitroso-nornicotine content. Field studies were conducted in Kentucky and Tennessee during the 2013 growing season, with 17 prospective parental lines and 20 prospective commercial varieties grown and compared to their original counterparts. Most of the e3 lines were not morphologically …