DNA markers linked to novel sources of resistance to eastern filbert blight inEuropean hazelnut (Corylus avellana L.)

The hundred-year history of the hazelnut industry in the Pacific Northwest is threatened by eastern filbert blight (EFB) caused by the fungus Anisogramma anomala (Peck) E. Müller. Marker-assisted selection (MAS) has been extensively used for ‘Gasaway’ resistance in the hazelnut breeding program at Oregon State University. Concern over breakdown of this resistance gene offers an incentive to look for new sources of resistance. Three genotypes (OSU 408.040, ‘Ratoli’ and OSU 759.010) have shown no signs or symptoms of the disease following a series of greenhouse inoculations or exposure of potted trees under structures topped with diseased wood. The objective of this study was to observe segregation for disease response in the offspring of these three novel sources and identify RAPD (Random Amplified Polymorphic DNA) markers linked to resistance. A total of 900 primers was screened for each resistance source using three resistant seedlings, three susceptible seedlings and the parents of a segregating population. The identified RAPD markers were then validated in a second progeny for each resistance source. Selection OSU 408.040, grown from seeds labeled “Weschcke hybrid” collected at the research farm of the University of Minnesota, transmitted resistance to half of its seedlings. Six RAPD markers (four in repulsion and two in coupling) linked to resistance were identified for the cross OSU 245.098 × OSU 408.040. A linkage map constructed with disease phenotypes, previously identified AFLP markers and newly identified RAPDs spanned a distance of 18 cM. The order of markers was similar in the progeny OSU 474.013× OSU 408.040. Segregation in two progenies indicated that the Spanish cultivar ‘Ratoli’ transmits resistance to 50% of its progeny. Four RAPD markers (one in repulsion and three in coupling) were identified for the progeny OSU 665.012 × 'Ratoli'. A linkage map constructed with disease phenotypes, previously identified AFLP markers and newly identified RAPDs spanned a distance of 28 cM. The RAPD marker OPG17-800 is robust, segregates 1:1, and has potential for use in MAS. Selection OSU 759.010 from the Republic of Georgia provides a new source of resistance. Disease scores segregated 3 resistant: 1 susceptible in the progeny OSU 759.010 × OSU 653.068, and 1 resistant : 1 susceptible in the progeny OSU 759.010 × OSU 665.076. Thirteen RAPD markers (12 in coupling and one in repulsion) linked to resistance were identified and a linkage map was constructed for the first progeny. All markers except OPH12-640 were also present in the second progeny. The markers closely linked to the resistance locus show distorted segregation in both progenies. Segregation ratios suggest simple inheritance for all three sources of resistance, and several RAPDs useful for marker-assisted selection were identified

Heat Transfer Mechanisms in Petroleum and Geothermal Wellbores

The flow of fluids between wells and reservoirs involves a substantial amount of thermal energy exchange with the formation. Understanding the mechanisms involved in the heat transfer of these processes is crucial to the design of the wells for mechanical integrity. While long term production scenarios may achieve a notional steady state, short term injection scenarios involve an accurate consideration of the thermal transients. With global initiatives towards a transition to clean energy, the design of geothermal wells is becoming an area of great importance these days. Accordingly, correct simulation of the heat transfer in the circulating scenario involved in closed loop wells enables accurate assessments of thermal power generated. This chapter aims to educate the user in how to tackle these problems and explains the physics and mathematics involved in detail

Exploring Folate Diversity in Wild and Primitive Potatoes for Modern Crop Improvement

Malnutrition is one of the world’s largest health concerns. Folate (also known as vitamin B₉) is essential in the human diet, and without adequate folate intake, several serious health concerns, such as congenital birth defects and an increased risk of stroke and heart disease, can occur. Most people’s folate intake remains sub-optimal, even in countries that have a folic acid food fortification program in place. Staple crops, such as potatoes, represent an appropriate organism for biofortification through traditional breeding based on their worldwide consumption and the fact that modern cultivars only contain about 6% of the daily recommended intake of folate. To start breeding potatoes with enhanced folate content, high folate potato material must be identified. In this study, 250 individual plants from 77 accessions and 10 Solanum species were screened for their folate content using a tri-enzyme extraction and microbial assay. There was a 10-fold range of folate concentrations among individuals. Certain individuals within the species Solanum tuberosum subsp. andigenum, Solanum vernei and Solanum boliviense have the potential to produce more than double the folate concentrations of commercial cultivars, such as Russet Burbank. Our results show that tapping into the genetic diversity of potato is a promising approach to increase the folate content of this important crop.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by MDPI. The published article can be found at: http://www.mdpi.com/journal/genesKeywords: andigenum, biofortification, folate, vitamin B₉, vernei, potato, Solanum tuberosu

Single nucleotide polymorphism (SNP) markers associated with high folate content in wild potato species

Micronutrient deficiency, also known as the hidden hunger, affects over two billion people worldwide. Potato is the third most consumed food crops in the world, and is therefore a fundamental element of food security for millions of people. Increasing the amount of micronutrients in food crop could help alleviate worldwide micronutrient malnutrition. In the present study, we report on the identification of single nucleotide polymorphism (SNP) markers associated with folate, an essential micronutrient in the human diet. A high folate diploid clone Fol 1.6 from the wild potato relative Solanum boliviense (PI 597736) was crossed with a low/medium folate diploid S. tuberosum clone USW4self#3. The resulting F1 progeny was intermated to generate an F2 population, and tubers from 94 F2 individuals were harvested for folate analysis and SNP genotyping using a SolCap 12K Potato SNP array. Folate content in the progeny ranged from 304 to 2,952 ng g-1 dry weight. 6,759 high quality SNPs containing 4,174 (62%) polymorphic and 2,585 (38%) monomorphic SNPs were used to investigate marker-trait association. Association analysis was performed using two different approaches: survey SNP-trait association (SSTA) and SNP-trait association (STA). A total of 497 significant SNPs were identified, 489 by SSTA analysis and 43 by STA analysis. Markers identified by SSTA were located on all twelve chromosomes while those identified by STA were confined to chromosomes 2, 4, and 6. Eighteen of the significant SNPs were located within or in close proximity to folate metabolism-related genes. Forty two SNPs were identical between SSTA and STA analyses. These SNPs have potential to be used in marker-assisted selection for breeding high folate potato varieties

Low-altitude, high-resolution aerial imaging systems for row and field crop phenotyping: A review

Global plant genetics research efforts have focused on developing high yielding, stress tolerant, and disease resistant row and field crop varieties that are more efficient in their use of agronomic inputs (water, nutrients, pesticides, etc.). Until recently, a key bottleneck in such research was the lack of high-throughput sensing technologies for effective and rapid evaluation of expressed phenotypes under field conditions for holistic data-driven decision making and variety selection. This review focuses on technological aspects of integrating unmanned aerial vehicles with imaging systems to enhance field phenotyping capabilities. The state-of-the-art of unmanned aerial vehicle technology for various applications including crop emergence, vigor, and characterization of yield potential of row and field crops has been reviewed. The potential of using aerial imaging to evaluate resistance/susceptibility to biotic and abiotic stress for crop breeding and precision production management has been discussed along with future perspectives and developments.Keywords: High-throughput field phenomics, Aerial imaging, Crop breeding, Data minin

Targhee Russet: A High Yielding, Dual Purpose Potato Variety with High Protein and Vitamin C Content and Resistance to Tuber Soft Rot

Targhee Russet is a darker-skinned russet potato variety that has shown higher total and marketable yields than Russet Burbank in most yield trials conducted in the western United States. A major strength of Targhee Russet is resistance to tuber soft rot, and it also has moderate resistance to common scab, Verticillium wilt, and net necrosis associated with Potato leafroll virus. Targhee Russet also has exhibited resistance to hollow heart and blackspot bruise. Analyses have shown Targhee Russet to have significantly higher tuber protein and Vitamin C content than Russet Burbank and Ranger Russet. It produces lighter colored fries out of storage than standard processing varieties, indicating its high potential for the production of premium quality frozen and fresh-cut fries. High merit scores for fresh use are also indicative of it having excellent potential as a dual-purpose russet variety, suitable for both processing and fresh-pack operations.This is the publisher’s final pdf. The article is copyrighted by The Potato Association of America and published by Springer. It can be found at: http://link.springer.com/journal/12230Keywords: Processing, Breeding, Variety, Solanum tuberosu