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81.
Matheus S. Barros Odilon P. Morais Júnior Patrícia G. S. Melo Orlando P. Morais Adriano P. Castro Flávio Breseghello 《Euphytica》2018,214(4):61
A plant breeding program is a long-term investment. Therefore, periodic assessment of the effectiveness of a breeding strategy is essential to maximize genetic gains per unit of time and resource invested. In this work, we assessed the effectiveness of the early-generation testing (EGT) approach used in the upland rice (Oryza sativa L.) breeding program at Embrapa (Brazilian Agricultural Research Corporation), Brazil, estimating the genetic progress achieved for three traits in two distinct phases, spanning 15 years. In the first phase (from 2003 to 2010), it was used the bulk method within F3 progenies with prior testing of F2 crosses, while in the second phase (from 2010 to 2017), it was used the bulk method within F2 progenies. The dataset comprised 70 yield trials, involving 1884 F3:5 progenies (phase I) and 925 F2:4 progenies (phase II) from an elite population, and 10 check cultivars, evaluated for grain yield (GY), plant height (PH) and days to flowering (DTF). For estimating the genetic gain, we adapted a generalized linear regression method to compute bi-segmented linear regression coefficients. Desirable genetic gains were achieved only for GY in both phases of the breeding program, with 78.75 kg ha?1 year?1 (2.68%) in the first phase, and 53.78 kg ha?1 year?1 (1.54%) in the second phase. These results show the effectiveness of EGT, especially via bulk method within F3 progenies with prior testing of F2 crosses, applied to upland rice breeding. Some refinements are discussed in the method to make it more cost-effective and more efficient in achieving genetic gains. 相似文献
82.
Nik G. Wiman Daniel T. Dalton Gianfranco Anfora Antonio Biondi Joanna C. Chiu Kent M. Daane Beverly Gerdeman Angela Gottardello Kelly A. Hamby Rufus Isaacs Alberto Grassi Claudio Ioriatti Jana C. Lee Betsey Miller M. Valerio Rossi Stacconi Peter W. Shearer Lynell Tanigoshi Xingeng Wang Vaughn M. Walton 《Journal of pest science》2016,89(3):653-665
83.
Hymenoptera wasps associated with the Asian gall wasp of chestnut (Dryocosmus kuriphilus) in Calabria,Italy 总被引:1,自引:0,他引:1
Vincenzo Palmeri Pasquale Cascone Orlando Campolo Saverio B. Grande Francesca Laudani Antonino Malacrinò Emilio Guerrieri 《Phytoparasitica》2014,42(5):699-702
The parasitoid complex of the Asian chestnut gall wasp Drycosmus kuriphilus Yasumatsu was studied in Calabria (Italy). A total of 14 different species of parasitoids were collected, of which three are recorded on the Asian gall wasp for the first time. The composition of the parasitoid complex collected in Calabria was compared with that reported from Italy and from Europe. The altitude of the sites of collection seemed to have an effect on the distribution and abundance of the single species of parasitoids. 相似文献
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85.
Ping Wang David B. Johnston Kent D. Rausch Shelly J. Schmidt M. E. Tumbleson Vijay Singh 《Cereal Chemistry》2009,86(3):319-322
The dry grind process using granular starch hydrolyzing enzymes (GSHE) saves energy. The amount of GSHE used is an important factor affecting dry grind process economics. Proteases can weaken protein matrix to aid starch release and may reduce GSHE doses. Two specific proteases, an exoprotease and an endoprotease, were evaluated in the dry grind process using GSHE (GSH process). The effect of protease and urea addition on GSH process was also evaluated. Addition of these proteases resulted in higher ethanol concentrations (mean increase of 0.3–1.8 v/v) and lower distillers' dried grains with solubles (DDGS) yields (mean decrease of 1.3–8.0% db) compared with the control (no protease addition). As protease levels and GSHE increased, ethanol concentrations increased and DDGS yields decreased. Protease addition reduced the required GSHE dose. Final mean ethanol concentrations without urea (15.2% v/v) were higher than with urea (15.0% v/v) in GSH process across all protease treatments. 相似文献
86.
Kent D. Rausch Larry E. Pruiett Ping Wang Li Xu Ronald L. Belyea M. E. Tumbleson 《Cereal Chemistry》2009,86(4):434-438
The objective was to describe a laboratory‐scale dry‐milling procedure that used single‐stage tempering and determine the effect of hybrid on yields and fraction compositions in milled corn. Samples of 11 commercially available hybrids were processed through a laboratory dry‐milling procedure that used 1 kg samples of corn to produce milling fractions of large grits, small grits, fines, germ, and pericarp. Compositions of milling fractions (protein, neutral detergent fiber, ash, and crude fat) were determined. The procedure used a single‐stage tempering step that increased corn moisture from 15 to 23.5% wb during an 18‐min tempering period. Germ were separated from endosperm particles using a roller mill followed by screening over a sieve with 1.68‐mm openings. Coefficients of variability were small, indicating acceptable repeatability. Overall yield means were 39.2, 25.3, 13.8, 78.2, 14.3, and 6.8 g/100 g (db) for large grits, small grits, fines, total endosperm, germ, and pericarp, respectively. There were effects due to hybrid (P < 0.05) on fraction yields and compositions of milling fractions. Correlations (r) among endosperm fractions (large grits, small grits, and fines) ranged from 0.54 to |–0.92|. Correlations among endosperm fractions and germ and pericarp were <0.68. The developed dry‐milling method estimated milling yields among hybrids with low standard deviations relative to the means and should be a useful tool for research and industry in measuring dry‐milling characteristics. 相似文献
87.
Santiago D. Gutierrez-Nibeyro Nathaniel A. White II Natasha M. Werpy Laurie Tyrrell Kent A. Allen Kenneth E. Sullins Richard D. Mitchell 《Veterinary radiology & ultrasound》2009,50(1):21-31
We report the use of a low-field magnetic resonance (MR) imaging system for the detection of desmopathy of the collateral ligament of the distal interphalangeal joint and the long-term outcome. Twenty horses were studied and their medical records and MR images were reviewed retrospectively. Long-term follow-up information was obtained by telephonic questionnaires of owners, trainers, or referring veterinarians. Desmopathy of the medial collateral ligament (80%) and enthesopathy of the affected collateral ligament (80%) were common MR imaging features. Treatment consisted of stall rest followed by a rehabilitation period. Additional treatments included shoeing, extracorporeal shock wave therapy, application of a half limb or foot cast, and medication of the distal interphalangeal joint. Twelve (60%) horses returned to their previous level of exercise and maintained their previous level, whereas eight horses had a poor outcome. Low-field MR imaging in the standing patient can be used to detect collateral ligament desmopathy of the distal interphalangeal joint without a need for general anesthesia. 相似文献
88.
A NOVEL,REMOVABLE, CERROBEND,BEAM‐BLOCKING DEVICE FOR RADIATION THERAPY OF THE CANINE HEAD AND NECK: PILOT STUDY
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Michael S. Kent Davide Berlato Isabelle Vanhaezebrouck Ira K. Gordon Katherine S. Hansen Alain P. Theon Randall W. Holt Earl A. Trestrail 《Veterinary radiology & ultrasound》2017,58(1):100-105
Radiation therapy of the head and neck can result in mucositis and other acute affects in the oral cavity. This prospective pilot study evaluated a novel, intraoral, beam‐blocking device for use during imaging and therapeutic procedures. The beam‐blocking device was made from a metal alloy inserted into a coated frozen dessert mold (Popsicle® Mold, Cost Plus World Market, Oakland, CA). The device was designed so that it could be inserted into an outer shell, which in turn allowed it to be placed or removed depending on the need due to beam configuration. A Farmer type ionization chamber and virtual water phantom were used to assess effects of field size on transmission. Six large breed cadaver dogs, donated by the owner after death, were recruited for the study. Delivered dose at the dorsal and ventral surfaces of the device, with and without the alloy block in place, were measured using radiochromic film. It was determined that transmission was field size dependent with larger field sizes leading to decreased attenuation of the beam, likely secondary to scatter. The mean and median transmission on the ventral surface without the beam‐blocking device was 0.94 [range 0.94–0.96]. The mean and median transmission with the beam‐blocking device was 0.52 [range 0.50–0.57]. The mean and median increase in dose due to backscatter on the dorsal surface of the beam‐blocking device was 0.04 [range 0.02–0.04]. Findings indicated that this novel device can help attenuate radiation dose ventral to the block in dogs, with minimal backscatter. 相似文献
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90.