Agriculture Commons^™

Drivers Of Spatial And Temporal Variation In Soybean Yield And Irrigation Requirements In The Western Us Corn Belt, Patricio Grassini, Jessica A. Torrion, Kenneth Cassman, Haishun Yang, James Specht

Department of Agronomy and Horticulture: Faculty Publications

Both rainfed and irrigated soybean production are important in Nebraska (western US Corn Belt), accounting for a respective 48 and 52% of the state’s soybean production of 7 Mt on a respective 55 and 45% share of the state soybean area of 1.9 Mha. To date, no assessment of factors that may account for regional and inter-annual variation in yield and irrigation amount has been performed. To accomplish that objective, we evaluated a database containing on-farm field yields and total irrigation amount used in those fields. These data have been collected annually from ca. 1000 soybean fields in six regions …

Qtl Architecture Of Reproductive Fitness Characters In Brassica Rapa, Jennifer M. Dechaine, Marcus T. Brock, Cynthia Weinig

All Faculty Scholarship for the College of the Sciences

Background

Reproductive output is critical to both agronomists seeking to increase seed yield and to evolutionary biologists interested in understanding natural selection. We examine the genetic architecture of diverse reproductive fitness traits in recombinant inbred lines (RILs) developed from a crop (seed oil) × wild-like (rapid cycling) genotype of Brassica rapa in field and greenhouse environments.

Results

Several fitness traits showed strong correlations and QTL-colocalization across environments (days to bolting, fruit length and seed color). Total fruit number was uncorrelated across environments and most QTL affecting this trait were correspondingly environment-specific. Most fitness components were positively correlated, consistent with life-history …

Switchgrass Yield And Quality With Multiple Fertilizer Applications And Harvest Dates, Thomas Clarkson Keene

Theses and Dissertations--Plant and Soil Sciences

Switchgrass (Panicum virgatum L.) is an important native warm-season grass for biomass and forage production in the U.S. This research determined the effect of fertilizer type (conventional, manure, and biosolids) and rate on switchgrass biomass yield and forage quality. Fertilizers were added at 0, 33, 67, 100, and 134 kg N ha^-1 on established stands of ‘Kanlow’ switchgrass in three northeastern Kentucky counties. Soils across sites ranged from recently cleared forestland (low pH, P, and K) to productive cropland (high pH, P and K). Stands were sampled for forage nutritive value in June, simulating a hay harvest. Nutritive …

Xanthium Strumarium L. Impact On Corn Yield And Yield Components, Zahid Hussain, Khan Bahadar Marwat, John Cardina, Ijaz Ahmad Khan

Turkish Journal of Agriculture and Forestry

Xanthium strumarium L. is a major weed affecting flour corn in Khyber Pakhtunkhwa Province of Pakistan. Studies conducted in 2006 and 2007 evaluated corn yield and yield component responses to competition from X. strumarium over a range of corn populations (5, 7.5, 10, and 12.5 plants m^{-2}) and X. strumarium densities (0, 2, 4, 6, 8, 10, and 12 plants m^{-2}). Flour corn yield and yield components (grains ear^{-1}, 1000-grain weight, harvest index, and days to silking) were significantly correlated with and affected by corn population, weed density, and the interaction between them. The percent reduction in grain yield was …

Impact Of Early Cropping On Vegetative Development, Productivity, And Fruit Quality Of Gala And Braeburn Apple Trees, Dragan D. Radivojevic, Jasminka M. Milivojevic, Cedo Dj. Oparnica, Todor B. Vulic, Boban S. Djordjevic, Sezai̇ Erci̇şli̇

Turkish Journal of Agriculture and Forestry

The effects of 5 crop load levels (all fruit removed and 10, 20, 30, and 40 fruit per tree) in the second growing year on vegetative growth, productivity, and fruit quality were studied in apple cultivars Gala and Braeburn on M9 rootstock in the second and the third leaf. An increase in vegetative growth was observed on the defruited trees in the second growing year. The highest crop load of 40 fruits per tree reduced average fruit weight by 18.7% in Gala compared to those obtained on the trees carrying the lowest crop load (10 fruits per tree). The reduction …

Hybrid Performance And Heterosis In F1 Offspring Of Triticale (× Triticosecale Wittm.), Mustafa Yildirim, Hasan Gezgi̇nç, Ali̇ Haydar Paksoy

Turkish Journal of Agriculture and Forestry

In this study, the combined ability effects and heterosis were determined for number of days to anthesis (AT), plant height (PH), fertile tillers plant^{–1} (FT), spike length (SL), spikelets spike–1 (SS) and grains spike–1 (GS), 1000-kernel weight (TW), and grain yield plant^{–1} (GY) of 4 triticale genotypes [Karma (G1), Presto (G2), Ayşehanım (G3), and Mehmetbey (G4)] and their 6 F_1 offspring. The mean squares of general combining ability (GCA) and specific combining ability (SCA) were statistically significant for all traits. According to the GCA/SCA, additive gene effects were found for all traits. According to the desired values for traits on …

Identification And Validation Of Quantitative Trait Loci For Seed Yield, Oil And Protein Contents In Two Recombinant Inbred Line Populations Of Soybean, Xianzhi Wang, Guo‑Liang Jiang, Marci Green, Roy A. Scott, Qijian Song, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean seeds contain high levels of oil and protein, and are the important sources of vegetable oil and plant protein for human consumption and livestock feed. Increased seed yield, oil and protein contents are the main objectives of soybean breeding. The objectives of this study were to identify and validate quantitative trait loci (QTLs) associated with seed yield, oil and protein contents in two recombinant inbred line populations, and to evaluate the consistency of QTLs across different environments, studies and genetic backgrounds. Both the mapping population (SD02- 4-59 × A02-381100) and validation population (SD02- 911 × SD00-1501) were phenotyped for …