Agriculture and Agri-Food Canada

About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.

Phytophthora sojae Avirulence Effector Avr3b is a Secreted NADH and ADP-ribose Pyrophosphorylase that Modulates Plant Immunity

Abstract: Plants have evolved pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) to protect themselves from infection by diverse pathogens. Avirulence (Avr) effectors that trigger plant ETI as a result of recognition by plant resistance (R) gene products have been identified in many plant pathogenic oomycetes and fungi. However, the virulence functions of oomycete and fungal Avr effectors remain largely unknown. Here, we combined bioinformatics and genetics to identify Avr3b, a new Avr gene from Phytophthora sojae, an oomycete pathogen that causes soybean root rot. Avr3b encodes a secreted protein with the RXLR host-targeting motif and C-terminal W and Nudix hydrolase motifs. Some isolates of P. sojae evade perception by the soybean R gene Rps3b through sequence mutation in Avr3b and lowered transcript accumulation. Transient expression of Avr3b in Nicotiana benthamiana increased susceptibility to P. capsici and P. parasitica, with significantly reduced accumulation of reactive oxygen species (ROS) around invasion sites. Biochemical assays confirmed that Avr3b is an ADP-ribose/NADH pyrophosphorylase, as predicted from the Nudix motif. Deletion of the Nudix motif of Avr3b abolished enzyme activity. Mutation of key residues in Nudix motif significantly impaired Avr3b virulence function but not the avirulence activity. Some Nudix hydrolases act as negative regulators of plant immunity, and thus Avr3b might be delivered into host cells as a Nudix hydrolase to impair host immunity. Avr3b homologues are present in several sequenced Phytophthora genomes, suggesting that Phytophthora pathogens might share similar strategies to suppress plant immunity.

Pasteurized processed cheese and substitute/imitation cheese products

Abstract: The products in this group differ from natural cheeses in that they are not made directly from milk (or dehydrated milk), but rather from various ingredients such as skim milk, natural cheese, water, butter oil, casein, casemates, other dairy ingredients, vegetable oils, vegetable proteins and/or minor ingredients. The two main categories, namely pasteurized processed cheese products (PCPs) and analogue cheese products (ACPs), may be subdivided further depending on the composition and the types and levels of ingredients used (Fig. 1). The individual categories will be discussed separately below.

Reinventing potato as a diploid inbred line-based crop

Abstract: The third most important food crop worldwide, potato (Solanum tuberosum L.) is a tetraploid outcrossing species propagated from tubers. Breeders have long been challenged by polyploidy, heterozygosity, and asexual reproduction. It has been assumed that tetraploidy is essential for high yield, that the creation of inbred potato is not feasible, and that propagation by seed tubers is ideal. In this paper, we question those assumptions and propose to convert potato into a diploid inbred line–based crop propagated by true seed. Although a conversion of this magnitude is unprecedented, the possible genetic gains from a breeding system based on inbred lines and the seed production benefits from a sexual propagation system are too large to ignore. We call on leaders of public and private organizations to come together to explore the feasibility of this radical and exciting new strategy in potato breeding. S.H. Jansky, USDA–ARS Vegetable Crops Research Unit, Dep. of Horticulture, Univ. of Wisconsin, 1575 Linden Dr., Madison, WI; A.O. Charkowski, Dep. of Plant Pathology, Univ. of Wisconsin, Madison, WI; D.S. Douches, Dep. of Plant, Soil, and Microbial Sciences, Mich. State Univ., East Lansing, MI; G. Gusmini, Pepsico, St. Paul, MN; C. Richael, Simplot Plant Sciences, Boise, ID; P.C. Bethke and D.M. Spooner, USDA–ARS Vegetable Crops Research Unit, Dep. of Horticulture, Univ. of Wisconsin, Madison, WI; R.G. Novy, USDA– ARS Small Grains and Potato Germplasm Research Unit, Aberdeen, ID; H. De Jong, Agriculture and Agri-Food Canada, Fredericton, New Brunswick, Canada (retired); W.S. De Jong, School of Integrative Plant Sciences, Cornell Univ., Ithaca, NY; J.B. Bamberg USDA–ARS, Dep. of Horticulture, Univ. of Wisconsin, Madison, WI, and US Potato Genebank, Sturgeon Bay, WI; A.L. Thompson, Dep. of Plant Sciences, North Dakota State Univ.; B. Bizimungu, Agriculture and Agri-Food Canada, Fredericton, New Brunswick, Canada; D.G. Holm, Dep. of Horticulture and Landscape Architecture, Colorado State Univ., San Luis Valley Research Center, Center, CO; C.R. Brown, USDA– ARS, Prosser, WA; K.G. Haynes, USDA–ARS, Beltsville, MD; V.R. Sathuvalli, Dep. of Crop and Soil Science, Oregon State Univ., Hermiston Agricultural Research and Extension Center, Hermiston, OR; R.E. Veilleux, Dep. of Horticulture, Virginia Tech, Blacksburg, VA; J.C. Miller, Jr., Dep. of Horticultural Sciences, Texas AM J.M. Bradeen, Dep. of Plant Pathology, Univ. of Minnesota, St. Paul, MN; J. Jiang, Dep. of Horticulture, Univ. of Wisconsin, Madison, WI. G. Gusmini is an employee of PepsiCo, Inc.; the views expressed in this presentation are those of the author and do not necessarily reflect the position or policy of PepsiCo Inc. C. Richael is an employee of Simplot Plant Sciences; the views expressed in this presentation are those of the author and do not necessarily reflect the position or policy of Simplot Plant Sciences. Received 3 Dec. 2015. Accepted 25 Jan. 2016. *Corresponding author (shelley.jansky@ars. usda.gov; shjansky@wisc.edu). Abbreviations: CIP, International Potato Center; ILs, introgression lines; RILs, recombinant inbred lines; TPS, true potato seed. Published in Crop Sci. 56:1412–1422 (2016). doi: 10.2135/cropsci2015.12.0740 © Crop Science Society of America | 5585 Guilford Rd., Madison, WI 53711 USA This is an open access article distributed under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Published July 7, 2016

Growth with high planktonic biomass in Shewanella oneidensis fuel cells

Abstract: Shewanella oneidensis MR-1 grew for over 50 days in microbial fuel cells, incompletely oxidizing lactate to acetate with high recovery of the electrons derived from this reaction as electricity. Electricity was produced with lactate or hydrogen and current was comparable to that of electricigens which completely oxidize organic substrates. However, unlike fuel cells with previously described electricigens, in which cells are primarily attached to the anode, at least as many of the S. oneidensis cells were planktonic as were attached to the anode. These results demonstrate that S. oneidensis may conserve energy for growth with an electrode serving as an electron acceptor and suggest that multiple strategies for electron transfer to fuel cell anodes exist.

Soil Microbial Biomass and Mineralizable Carbon of Water‐Stable Aggregates

Abstract: Biophysical alterations of agricultural soils following adoption of zero tillage (ZT) deserve investigation in order to better understand the processes of soil organic C (SOC) sequestration and turnover. We determined the vertical distribution of soil microbial biomass C (SMBC), C mineralized in 24 d under standard conditions, and basal soil respiration (BSR) in five water-stable aggregate classes. Four soils (loam, silt loam, clay loam, and clay) from the Peace River region of northern Alberta and British Columbia were sampled following 4 to 16 yr under comparison of conventional shallow tillage (CT) and ZT. Macroaggregates (>0.25 mm) had greater SMBC, more C mineralized in 24 d, and higher BSR than microaggregates at a depth of 0 to 50 mm. Differences between macro- and microaggregates in these properties decreased with soil depth. Carbon mineralized in 24 d and SMBC were 9 ± 9% greater (mean of four soils ± standard deviation among soils) under ZT than under CT in macroaggregates, but were 6 ± 11% lower in whole soil due to lower amounts in microaggregates under ZT than under CT. Macroaggregate-protected SOC to a depth of 200 mm was 6.7 ± 1.9 g m -2 under CT and 9.8 ± 2.6 g m -2 under ZT. Soil organic C in macroaggregates, which had high concentrations of active pools of SOC, appeared to have been shunted into the more stable microaggregate fraction after disturbance with CT. Unlike in temperate, humid climates, decomposition of SOC during the passage from macro- to microaggregates may have been limited by the frigid, semiarid climate.