scholarly journals GENETICS OF FLOWERING HABIT IN STRAWBERRY: A MAP-BASED APPROACH

HortScience ◽  
1996 ◽  
Vol 31 (6) ◽  
pp. 913C-913
Author(s):  
Thomas M. Davis ◽  
M. Sean Hill ◽  
Rebecca S. Gallien ◽  
James E. Pollard
Keyword(s):  
Bulked Segregant Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dominant Gene ◽  
Recessive Gene ◽  
Late Summer ◽  
Early Summer ◽  
Genetic Determinants ◽  
Mature Fruit ◽  
Short Day ◽  
Early Fall

Strawberry flowering habit can be classified as either day-neutral (DN) or short-day (SD), depending on whether plants are insensitive or sensitive to photoperiod, respectively. Short-day (SD) cultivars produce mature fruit for just a few weeks in early summer. New floral initiation does not commence until triggered by the combination of short daylength and low temperature in the fall. Day-neutral (DN) cultivars do not require particular daylength conditions to initiate flowering, and so continue to produce flowers and mature fruit into late summer and early fall. We are using a map-based approach to characterize the genetic determinants of flowering habit in strawberry at both the diploid and octoploid levels. A recessive gene conferring DN flowering habit has been identified, and its position determined with respect to molecular markers on the Fragaria vesca genetic linkage map. We are using the technique of bulked segregant analysis (BSA) in an effort to find random amplified polymorphic DNA (RAPD) markers linked to a putative dominant gene conferring the DN habit in the octoploid, cultivated strawberry, F. ánanassa.

scholarly journals A biodiversity hotspot for Microgastrinae (Hymenoptera, Braconidae) in North America: annotated species checklist for Ottawa, Canada

ZooKeys ◽  
2016 ◽  
Vol 633 ◽  
pp. 1-93 ◽  
Author(s):  
Jose Fernandez-Triana ◽  
Caroline Boudreault ◽  
Joel Buffam ◽  
Ronald Maclean
Keyword(s):  
North America ◽  
General Pattern ◽  
Late Summer ◽  
The United States ◽  
Early Summer ◽  
Individual Species ◽  
Early Fall ◽  
Two Peaks ◽  
Annotated Checklist ◽  
First Time

Microgastrinae wasps (Hymenoptera, Braconidae) from the city of Ottawa and its surroundings (a 50-km radius circle, ~7,800 km2) were studied based on 1,928 specimens collected between 1894 and 2010, and housed in the Canadian National Collection of Insects. A total of 158 species from 21 genera were identified, which is by far the highest number of species ever recorded for a locality in North America. An annotated checklist of species is provided.Choerasparasitellae(Bouché, 1834) andPholetesornanus(Reinhard, 1880) are recorded for the first time in the Nearctic (previously only known from the Palearctic region),Cotesiadepressa(Viereck, 1912) is recorded for the first time in Canada (previously only known from the United States), andCotesiahemileucae(Riley, 1881) andProtapantelesphlyctaeniae(Muesebeck, 1929) are recorded for the first time in the province of Ontario. In Ottawa the most diverse genera areCotesia,Apanteles,Microplitis,Pholetesor,Microgaster, andDolichogenidea, altogether comprising 77% of the species found in the area. A total of 73 species (46%) were represented by only one or two specimens, suggesting that the inventory for Ottawa is still relatively incomplete. Seasonal distribution showed several peaks of activity, in spring, summer, and early fall. That general pattern varied for individual species, with some showing a single peak of abundance either in the summer or towards the end of the season, others species attaining two peaks, in late spring and late summer, or in early summer and early fall, and yet others attaining up to three different peaks, in spring, summer and fall. At least 72 of the Microgastrinae species from Ottawa have been previously associated with 554 species of Lepidoptera as hosts – but those historical literature records are not always reliable and in many cases are based on data from areas beyond Ottawa. Thus, our knowledge of the associations between the 158 species of microgastrine parasitoids and the caterpillars of the 2,064 species of Lepidoptera recorded from Ottawa is still very incomplete.

scholarly journals The COVID States Project #66: September 2021 update on executive approval

2021 ◽  
Author(s):  
Alauna Safarpour ◽  
Alexi Quintana ◽  
Matthew Baum ◽  
David Lazer ◽  
Katherine Ognyanova ◽  
...  
Keyword(s):  
National Policy ◽  
Late Summer ◽  
The Elderly ◽  
Early Summer ◽  
Policy Decisions ◽  
Public Places ◽  
Public Health Agencies ◽  
Department Of Labor ◽  
Early Fall ◽  
The U.S

The COVID States Project survey regularly asks people in all 50 states about their approval of their governors and the President. Since our last report on executive approval, which examined trends through March 2021, the pandemic has notably evolved, with huge surges of cases and deaths associated with the Delta variant throughout the summer and early fall. Most states reacted to the dip in coronavirus infections and increase in vaccinations in late spring and early summer by lifting indoor mask mandates, only to struggle to adapt as cases surged again in the late summer and early fall 2021. Some of these states were responding to CDC guidance, which announced in May that fully vaccinated people no longer needed to wear masks indoors or outdoors, only to reverse that guidance a few months later and recommend masks indoors for Americans living in areas of high transmission regardless of vaccination status. Other states rebuffed the guidance of public health agencies by, for instance, banning mask mandates in schools, businesses, and other public places. These policy decisions received wide criticism1 particularly as COVID-19 cases, hospitalizations, and deaths surged in those states with the loosest pandemic restrictions.September 2021 has also seen important political developments with respect to national policy around COVID-19. On September 9, President Biden issued an executive order requiring all federal employees and government contractors to be vaccinated. The President also announced that the U.S. Department of Labor would require all businesses with more than 100 employees to require vaccination or weekly testing and provide paid time off for employees to get vaccinated. On September 22, the FDA authorized booster shots for those vaccinated with the Pfizer/BioNTech vaccine for certain populations, including the elderly and those at higher risk of catching the disease due to their professions.In this report, we examine the approval of governors and the President for their handling of the pandemic -- and for the president's overall approval -- over time across the U.S. to assess how the public reacted to the policy decisions and developments surrounding the pandemic as well as state and federal governmental responses.

Seasonal changes in activity patterns and the adaptive value of haying in pikas (Ochotona princeps)

1983 ◽  
Vol 61 (2) ◽  
pp. 411-416 ◽  
Author(s):  
Douglas A. Conner
Keyword(s):  
Surface Activity ◽  
Seasonal Changes ◽  
Activity Patterns ◽  
Winter Season ◽  
Late Summer ◽  
Early Summer ◽  
Cold Temperatures ◽  
Vegetation Growth ◽  
Ochotona Princeps ◽  
Early Fall

Seasonal changes in the performance of four behaviors, perching, haying, feeding, and surface activity were studied in two populations of North American pikas (Ochotona princeps) living in Colorado. During late summer and early fall (July–September), haying, the gathering of meadow vegetation followed by storing it in their talus territories, made up almost 55% of the pikas' surface activity. After haying ceased, pikas continued to feed in the meadows until snowpack, cold temperatures, and the absence of surface vegetation made this impossible. Beginning in February, individuals remained under the snowpack feeding on vegetation from their hay piles and on lichens available below the snow. Surface activity was not seen again until May when spring vegetation began to appear. Haying appears to be an adaptive response to environmental unpredictability. Hay piles most likely become critical for survival when harsh weather prevents surface foraging and(or) delays the emergence of new vegetation growth in the spring or early summer. It is suggested that the evolution of territoriality in pikas is related to the need to gather sufficient vegetation to serve as a potential winter food supply during years when the winter season is unusually harsh or prolonged.

Environmental Influence on Bentgrass Treated with Silvex

Weed Science ◽  
1968 ◽  
Vol 16 (2) ◽  
pp. 193-196 ◽  
Author(s):  
Lloyd M. Callahan ◽  
Ralph E. Engel ◽  
Richard D. Ilnicki
Keyword(s):  
Environmental Influence ◽  
Late Summer ◽  
Creeping Bentgrass ◽  
Early Summer ◽  
Low Ph ◽  
Agrostis Palustris ◽  
High Moisture ◽  
Early Fall ◽  
Moisture Conditions ◽  
Long Photoperiod

Colonial bentgrass (Agrostis tenuis Sibth) and creeping bentgrass (Agrostis palustris Huds) exhibited the most tolerance to 1/2, 1, 1 1/2, and 3 lb/A of 2-(2,4,5-trichlorophenoxy)propionic acid (silvex) when grown under cool temperatures, a long photoperiod, and a low pH medium. Injury from treatments was slight to moderate when applied from early to mid-spring, severe when made from late spring to early summer, and very severe when made from late summer to early fall. Silvex appeared to cause the most injury at the 1 and 1 1/2 lb/A rates. Injury was much less from the lower rate of 1/2 lb/A. Root fructosan concentrations decreased with increasing rates under cool temperatures and increased with increasing rates under high temperatures. Bentgrass appeared to tolerate silvex treatments better under low available moisture conditions than under high moisture levels.

scholarly journals Identification and Characterization of Random Amplified Polymorphic DNA Markers Linked to a Major Gene (Cr2) for Resistance to Cronartium ribicola in Pinus monticola

2006 ◽  
Vol 96 (4) ◽  
pp. 395-399 ◽  
Author(s):  
Jun-Jun Liu ◽  
Abul K. M. Ekramoddoullah ◽  
Rich S. Hunt ◽  
Arezoo Zamani
Keyword(s):  
Dna Markers ◽  
Positional Cloning ◽  
Rapd Markers ◽  
Bulked Segregant Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dominant Gene ◽  
Cronartium Ribicola ◽  
R Genes ◽  
Pinus Monticola ◽  
White Pine

DNA markers tightly linked to resistance (R) genes provide a very powerful tool for both marker-assisted selection in plant breeding and positional cloning of R genes. In the present study, a linkage of random amplified polymorphic DNA (RAPD) markers to the single dominant gene (Cr2) for resistance to white pine blister rust fungus (Cronartium ribicola) was investigated in western white pine (Pinus monticola). A mapping population of 128 individual megagametophytes was generated from seeds of a heterozygous resistant tree (Cr2/cr2), and the corresponding seedlings of each megagametophyte were subjected to the test of phenotype segregation by inoculation with C. ribicola. Bulked segregant analysis and haploid segregation analysis identified eight robust RAPD markers linked to Cr2. This constitutes the first Cr2 genetic linkage map spanning 84.7 cM with four markers only 3.2 cM from Cr2. One sequence (U256-1385) of these linked markers was significantly similar to the Ty3/gypsy-like long terminal direct repeats retrotransposons. Another marker, U570-843, had no significant similarity to any entry in either GenBank or the loblolly genomics data bank. As presumed that the average physical distance per centimorgan is about 10 Mb in P. monticola, it is probably unrealistic to use these DNA markers for positional cloning of the Cr2 gene.

scholarly journals Genetic Mapping of PcDw Determining Pear Dwarf Trait

2011 ◽  
Vol 136 (1) ◽  
pp. 48-53 ◽  
Author(s):  
Caihong Wang ◽  
Yike Tian ◽  
Emily J. Buck ◽  
Susan E. Gardiner ◽  
Hongyi Dai ◽  
...  
Keyword(s):  
Ssr Markers ◽  
Rapd Markers ◽  
Bulked Segregant Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dominant Gene ◽  
Pyrus Pyrifolia ◽  
Chi Square ◽  
Sequence Characterized Amplified Regions ◽  
Chi Square Analysis ◽  
Simple Sequence

European pear (Pyrus communis) ‘Aihuali’ carrying the dwarf character originating from ‘Nain Vert’ was crossed with ‘Chili’ (Pyrus bretschneideri). A total of 352 F1 progenies was produced to investigate the inheritance of the dwarf trait, and 111 of these were used to develop molecular markers. Chi-square analysis showed that the character fitted a 1:1 ratio indicative of a single dominant gene, which we have named PcDw. Using a bulked segregant analysis approach with 500 random amplified polymorphic DNA (RAPD) and 51 simple sequence repeat (SSR) markers from pear (Pyrus pyrifolia and P. communis) and apple (Malus ×domestica), four markers were identified as cosegregating with the dwarf character. Two of these were fragments produced by the S1212 and S1172 RAPD primers, and the other two were the pear SSR markers KA14 and TsuENH022. The RAPD markers were converted into sequence-characterized amplified regions (SCARs) and designated S1212-SCAR318 and S1172-SCAR930 and, with the SSR markers KA14 and TsuENH022, were positioned 5.9, 9.5, 8.2, and 0.9 cM from the PcDw gene, respectively. Mapping of the KA14 and TsuENH022 markers enabled the location of the PcDw gene on LG 16 of the pear genetic linkage map.

scholarly journals Molecular Markers for Septoria Leaf Spot (Septoria lycopersicii Speg.) Resistance in Tomato (Solanum lycopersicum L.)

2015 ◽  
Vol 3 (1) ◽  
pp. 40-47
Author(s):  
Bal K Joshi ◽  
Frank J Louws ◽  
G Craig Yenco ◽  
Byron R Sosinski ◽  
Consuelo Arellano ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Solanum Lycopersicum ◽  
Leaf Spot ◽  
Bulked Segregant Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dominant Gene ◽  
Segregation Ratio ◽  
Solanum Lycopersicum L ◽  
F2 Population ◽  
Septoria Leaf Spot

Marker assisted selection (MAS) has not been initiated in tomato (Solanum lycopersicum L.) for septoria leaf spot (SLS) resistance caused by Septoria lycopersici Speg due to lack of molecular markers. We studied the inheritance of SLS resistance and identified molecular markers linked to SLS resistance using bulked segregant analysis (BSA) in a segregating F2 population. Tomato inbred lines, NC 85L-1W (2007), susceptible to SLS and NC 839-2(2007)-1, resistant to SLS were used to develop the segregating population. A total of 250 F2 plants, and 10 plants each of P1, P2 and F1 were grown at the Mountain Horticultural Crops Research and Extension Center (MHCREC), Mills River NC in the summer of 2009. Disease severity was scored using a scale of 0 to 5, where 0 = no disease and 5 = complete development of disease. DNA was extracted from 2-3 week old plants and parental lines were screened with a total of 197 random amplified polymorphic DNA (RAPD) primers, of which 34 were polymorphic. Two DNA bulks, called resistant bulk (RB) and susceptible bulk (SB) were prepared from the F2 individuals. The RB and SB consisted of 8 individuals each with disease scores of 0, and 4.0 or 4.5, respectively. The segregation ratio of resistant and susceptible plants in F2 generation fit the expected Mendelian ratio of 3:1 for a single dominant gene. Five RAPD markers were linked to the SLS disease reaction, of which two were linked to susceptibility and three to the resistance. Subject to verification in independent populations, these markers may be useful for MAS of SLS resistance in tomato.Nepal Journal of Biotechnology. Dec. 2015 Vol. 3, No. 1: 40-47

scholarly journals Identification of Markers Linked to Seedlessness in Citrus kinokuni hort. ex Tanaka and Its Progeny Using Bulked Segregant Analysis

HortScience ◽  
2011 ◽  
Vol 46 (5) ◽  
pp. 693-697 ◽  
Author(s):  
Dario J. Chavez ◽  
José X. Chaparro
Keyword(s):  
Molecular Markers ◽  
Linkage Group ◽  
Bulked Segregant Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Dominant Gene ◽  
Segregation Ratio ◽  
Single Dominant Gene ◽  
Citrus Breeding

Citrus kinokuni ‘Mukaku kishu’ PI539530 and its progeny were studied to identify random amplified polymorphic DNA (RAPD) primers associated with seedlessness. Ninety-one F1 [(Robinson op) × C. kinokuni] individuals showed a 1:1 segregation ratio between seedless and seeded phenotypes with seedless as a single dominant gene. Bulked segregant analysis was used to identify markers associated with the seedless locus. Eighteen RAPD primers were mapped into a partial linkage group (≈55.8 cM length) with four RAPD primers flanking the seedless locus: OPAI11-0.8 at 8.7 cM, OPAJ19-1.0 at 8.4 cM, OPM06r-0.85 at 4.3 cM, and OPAJ04r-0.6 at 6.4 cM. The identification of molecular markers linked to C. kinokuni Fs seedless locus constitutes an important and major tool for citrus breeding and selection.

Effects of Dried Distillers’ Grains Cube Supplementation for Steers Grazing Introduced Pastures on Animal Performance and Forage Production

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 12-13
Author(s):  
Jordan Adams ◽  
Rodney Farris ◽  
Scott Clawson ◽  
Earl Ward ◽  
Paul Beck
Keyword(s):  
Festuca Arundinacea ◽  
Statistical Power ◽  
Cynodon Dactylon ◽  
Animal Health ◽  
Late Summer ◽  
Early Summer ◽  
Distillers Grains ◽  
Forage Production ◽  
Trenbolone Acetate ◽  
Dried Distillers Grains

Abstract We evaluated the effects of supplementing dried distillers’ grains cubes (DDGS) and re-implantation of steers (n = 149; BW = 238 ± 13.8 kg) grazing tall fescue (Festuca arundinacea)/bermudagrass (Cynodon dactylon) pastures (n = 9 pastures, 7.2 ± 2.90 ha) from 14 April to 17 September 2020 (n = 155 d) in a split-plot design on steer performance and forage production. Main plot supplemental treatments (n = 3 pastures/treatment) included 1) Fertilized Control (FC), no supplementation on fertilized pastures (112 kg N/ha); 2) Fertilized Supplement (FS), supplemental DDGS fed at 2.9 kg 3-d/wk on fertilized pastures; and 3) Supplement (S), supplemented DDGS at 0.75% BW/d on unfertilized pastures prorated for 5-d/wk feeding. Steers were previously implanted during receiving with 40 mg trenbolone acetate and 8 mg estradiol (REV-G; Revalor G, Merck Animal Health). On July 7, steers in each pasture were randomly assigned to one of three re-implant treatments: 1) no re-implant; 2) REV-G; or 3) 200 mg progesterone and 20 mg estradiol (Synovex S, Zoetis Animal Health). Steers in FS and S gained more (P < 0.01) than FC throughout the trial and final BW was greater (P < 0.01) for FS and S compared with FC. Unexpectedly, re-implanting had no effect on ADG (P = 0.57) or BW (P = 0.34), but statistical power may be lacking. Supplemental efficiency was greater in the late summer for FS (P = 0.05) compared to S. Fertilizing pastures in FS and FC did not affect biomass (P = 0.39), however, CP was increased (P = 0.01) and acid and neutral detergent fibers tended to decrease (P = 0.06) relative to S in the early summer (April, May, June, and July), but did not differ in late summer (August and September). Based upon our analysis, DDGS is a suitable supplement and can replace N fertilizer for steers grazing introduced pastures.

scholarly journals 179 Using a 100% Dried Distillers Grains Cube as a Supplement for Steers Grazing Mixed Grass Prairie in Oklahoma

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 46-46
Author(s):  
Zane N Grigsby ◽  
Paul A Beck ◽  
Stacey A Gunter
Keyword(s):  
Animal Health ◽  
Late Summer ◽  
Estradiol Benzoate ◽  
Positive Control ◽  
Negative Control ◽  
Early Summer ◽  
Trenbolone Acetate ◽  
Mixed Grass Prairie ◽  
Mixed Grass ◽  
Main Plot

Abstract This research was conducted to determine effects of supplementation and implanting on BW gain by steers grazing mixed grass prairie (n = 12 pastures, 19.9 ± 0.7 ha) in northwest Oklahoma. Three main plot treatments were: 1) Negative Control (NC), no supplementation, 2) Positive Control (PC), supplemented with DDGS cubes, 1.8 kg/steer on alternate days in late summer, 3) High Supplement (HS), 1/3 increase in stocking rate with 0.75% BW supplemental DDGS cubes all season. Steers (n = 125, BW = 223.1 ± 23.2 kg) were stocked at 2.2 ha/steer for PC and NC, 1.3 ha/steer for HS. Grazing was from May 17 – September 27 (132 d). All steers were implanted with 200 mg progesterone and 20 mg estradiol benzoate (SYN, Synonvex S, Zoetis Animal Health) on May 17. On July 18 three reimplant treatments were applied: 1) no reimplant; 2) SYN; or 3) 40 mg trenbolone acetate and 8 mg estradiol (Revalor G, Merck Animal Health). Data were analyzed using the PROC MIXED in SAS as a split-plot experimental design. In early summer HS had 0.26 kg greater (P < 0.01) ADG than NC and PC. Late summer gains of PC were 0.33 kg/d more (P ≤ 0.01) than NC; and HS gained 0.49 and 0.16 kg/day more (P ≤ 0.04) than NC and PC, respectively. Gain per hectare for PC (46 kg/ha) were greater (P < 0.01) than NC (35 kg/ha) and more than doubled (P < 0.01) with HS (89 kg/ha). Reimplanting had no effect on ADG (P ≥ 0.28). Late season supplementation with PC resulted in supplemental efficiency of 2.7 kg supplement/kg added gain compared with NC. Increased stocking rates with season long supplementation in HS resulted in supplemental efficiency of 3.8 kg supplement/kg added gain per hectare. Based on these data, a 100% DDGS cube is an effective supplement option to increase BW gain during the late summer or increase carrying capacity and gain during the summer grazing period in northwestern Oklahoma.

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