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Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

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Journal of Animal Science and Biotechnology 2012年第4期3卷 221-226页

作者： Stacey A Gunter Whitney A Whitworth T Gregory Montgomery Paul A Beck United States Department of Agriculture Agricultural Research Service Southern Plains Range Research Station University of Arkansas at Monticello Division of Agriculture Southeast Research & Extension Center University of Arkansas Division of Agriculture Southwest Research & Extension Center University of Arkansas

In December of 3 years, 87 beef cows with nursing calves （.594 ± 9.8 kg; calving season, September to November） at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures （0.45 ha/cow） that had been interseeded into a dormant common bermudagrass （Cynodon dactylon [L.] Pers.）/bahiagrass （Paspalum notatum Flugge） sod. Pastures contained 1 of the following 3 seeding mixtures （2 pastures/mixture）： 1） wheat （Triticum aestivurn L.） and ryegrass （Lofium multiflorum Lain., WRG）, 2） wheat and ryegrass plus red clover （Trifolium pretense L, WRR）, or 3） wheat and ryegrass plus white （Trifofium repens L.） and crimson clovers （Trifolium incarnatum L., WRW）. All groups had ad libitum access to grass hay （12% crude protein; 58% total digestible nutrients）. The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ （P ≥ 0.27） among cows between February and June. Calf birth weights or average daily gain did not differ （P≥ 0.17） among treatments; however, calves grazing pastures with clovers did tend （P= 0.06） to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater （P= 0.02） for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures.

关键词： Annual ryegrass Beef cows Clovers Nitrogen Pasture 1

Development of genome-wide insertion/deletion markers in rice based on graphic pipeline platform

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Journal of Integrative Plant Biology 2015年第11期57卷 980-991页

作者： Yang L Xiao Cui Rui Li Piaopiao Huang Jie Zong Danqing Yao Gang Li Dabing Zhang Zheng Yuan State Key Laboratory of Hybrid Rice School of Life Sciences and BiotechnologyShanghai Jiao Tong University Novel Bioinformatics Company Shanghai Agricultural Technology extension and service Center

DNA markers play important roles in plant breed- ing and genetics. The Insertion/Deletion （InDel） marker is one kind of co-dominant DNA markers widely used due to its low cost and high precision. However, the canonical way of searching for InDel markers is time-consuming and labor- intensive. We developed an end-to-end computational solution （InDel Markers Development Platform, IMDP） to identify genome-wide InDel markers under a graphic pipeline environment. IMDP constitutes assembled genome sequen- ces alignment pipeline （AGA-pipe） and next-generation re- sequencing data mapping pipeline （NGS-pipe）. With AGA-pipe we are able to identify 12,944 markers between the genome of rice cultivars Nipponbare and 93-11. Using NGS-pipe, we reported 34,794 InDels from re-sequencing data of rice cultivars Wu-Yun-Geng7 and Guang-Lu-Ai4. Combining AGA- pipe and NGS-pipe, we developed 2o5,659 InDels in eight japonica and nine indica cultivars and 2,681 InDels showed a subgroup-specific pattern. Polymerase chain reaction （PCR） analysis of subgroup-specific markers indicated that the precision reached 90% （86 of 95）. Finally, to make them available to the public, we have integrated the InDels/markers information into a website （Rice InDel Marker Database, RIMD, http：I/2o2.12o.45.71/）. The application of IMDP in rice will facilitate efficiency for development of genome-wide InDel markers, in addition it can be used in other species with reference genome sequences and NGS data.

关键词： Genetic polymorphism genome alignment InDel marker molecular breeding next-generation sequencing

An expedited method for isolation of DNA for PCR from Magnaporthe oryzae stored on filter paper

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The Crop Journal 2014年第5期2卷 267-271页

作者： Yulin Jia Yeshi A. Wamishe Bo Zhou USDA Agricultural Research service Dale Bumpers National Rice Research Service University of AR Cooperative extension service Plant Breeding Genetics and Biotechnology International Rice Research Institute

The fungus Magnaporthe oryzae is the causal agent of a wide range of cereal diseases. For long-term preservation, the fungus is grown and stored desiccated on filter papers at –20 °*** filter papers are cut into pieces of 0.5–1.0 cm diameter prior to storage. In the present study, a fast(11 min) and simple method of preparing DNA suitable for amplifying avirulence genes of M. oryzae by polymerase chain reaction(PCR) was developed. A piece of filter paper containing the fungus was removed from a glass bottle and placed in a 0.2 mL Eppendorf tube containing 100 μL 10 × TE. The suspension was heated for 10 min at 95 °C in a PCR machine. The tube was then centrifuged for 1 min at 3000 r min-1. One μL of 10 × TE solution containing DNA was used for PCR. A total of 28 samples were PCR tested. As a positive control, fungal DNA was extracted using a conventional DNA preparation method. DNA samples obtained from both methods were stored at 4 °C. PCR was performed with DNA on the preparation day and after 4, 8,10, and 18 days of refrigerated storage. In four samples, samples 12, 13, 14, and 28, AVR-Pi9 failed to be amplified. These four samples were tested with a different set of primers for AVR-Pi9, and for AVR-Pita1, confirming that the quality of the samples was insufficient for PCR. Overall, for nearly 90%(24/28) of the samples, the quality of the DNA prepared directly from the fungus on filter paper appeared suitable for a rapid survey of genetic identity of the rice blast fungus by *** method will be useful and effective for reducing cost and time and could readily be adopted worldwide for analysis of M. oryzae and possibly other fungi.

关键词： AVR-Pita1 Gene identification DNA extraction PCR Ten × TE

Sensitivity Comparison of Immunocapture PCR and Classical PCR for Detection of Burkholderia glumae

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Plant Diseases and Pests 2015年第3期6卷 5-9,19页

作者： Luo Jinyan Liu Hui Chen Lei Wu Hanbing Shanghai Agro-Technical extension and service Center National Agro-Technical extension and service Centre Pudong New Area Agro-Technical extension Centre

The present study combined the fluoride ion-selective electrode （ISE） method with classical PCR to increase the detection efficiency of Burkholderia glumae. The four antisera of rabbit anti whole cell of B. glumae had been successfully obtained by polyclonal antibody technique, which were ASBgl4, ASBg32, ASBg26 and ASBg04, respectively. The titers of four antisera reached 1：32 in ODD test and 1：5 120 in agglutination reaction. All antisera were identified to be qualified antibodies through combined method. The specificity of ASBgl4 and ASBg32 was very high, but that of ASBg26 and ASBg04 was not very satisfying. The results showed that all tested strains of B. glumae produced 500 bp specific fragments by direct PCR and immunocapture PCR detection, while others showed nega- tive PCR result. Comparing the sensitivity of these two detection methods, direct PCR could detect about 1 x 105 cfu/mL of bacterial suspension while immunocap- ture PCR could detect as few as 1× 103 cfu/mL, 102 times higher than direct PCR in sensitivity. In the detecting experiments of artificially inoculated seeds, at least two seeds were required in direct PCR, while only one seed was enough for immunocapture PCR detection.

关键词： Inununocapture PCR Rice Burkholderia glumae

Reducing dietary sodium of dairy cows fed a low-roughages diet affect intake and feed efficiency,but not yield

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Animal Nutrition 2023年第1期12卷 1-6页

作者： Yehoshav A.Ben Meir Yoav Shaani Daniel Bikel Yuri Portnik Shamai Jacoby Uzi Moallem Joshua Miron Eyal Frank Department of Ruminant Science Institute of Animal ScienceAgricultural Research Organization(ARO)Rishon Lezion 7528809Israel Department of Animal Production Extension ServiceMinistry of AgricultureRishon Lezion 7528809Israel

Wastewater from dairy farms has become a major environmental and economical *** residue in treated and untreated wastewater from dairy farms used for irrigation can lead to soil and groundwater salinization,with the risk of soil *** examined the effect of reducing sodium fed to mid to late lactating cows from 0.61%(high sodium[HS])to 0.45%(low sodium[LS])of dry matter on dry matter intake(DMI),milk and milk-component yields,eating behavior,apparent total track digestibility,feed efficiency,and sodium excretion into the *** randomly assigned 28 multiparous high-yielding(>35 kg milk/d)cows to 1 of 2 treatment groups(LS or HS)in a crossover design,with 7 d of adaptation and 28 d of data *** sodium in the diet reduced sodium intake from 171 to 123 g/d while lowering sodium excreted in the manure by 22%.Energy corrected milk(ECM)yield(37.4 kg/d)and sodium excretion in the milk(33.7 g/d)were similar for both *** DMI of LS cows was lower than that of HS cows(27.3 vs.28 kg/d)and consequently,feed efficiency of the LS cows was higher(1.40 vs.1.35 ECM/DMI).Eating rate,meal and visit frequency,and eating time were similar for both treatments;meal and visit duration were longer for the HS cows,and meal and visit sizes tended to be *** of DM and amylase-treated neutral detergent fiber remained *** on the results of this study,and discussed considerations,we recommend lowering the dietary sodium content for mid to late lactating cows in commercial herds to 0.52%of DM,in order to reduce sodium excretion to the environment via urine.

关键词： Mineral absorption Sodium Eating behavior Environmentally friendly dairy farm

Nmnoparticle-mediated double-stranded RNA delivery system: A promising approach for sustainable pest management

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Insect Science 2021年第1期28卷 21-34页

作者： Shuo Yan Bin-Yuan Ren Jie Shen Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural UniversityBeijingChina National Agricultural Technology extension and service Center BeijingChina

RNA interference(RNAi)targeting lethal genes in insects has great potential for sustainable crop *** with traditional double-stranded(ds)RNA delivery systems,nanoparticles such as chitosan,liposomes,and cationic dendrimers offer advantages in delivering dsRNA/small interfering(si)RNA to improve RNAi efficiency,thus promoting the development and practice of RNAi-based pest management ***,we illustrate the limitations of traditional dsRNA delivery systems,reveal the mechanism of nanoparticle-mediated RNAi,summarize the recent progress and successful applications of nanoparticle-mediated RNAi in pest management,and finally address the prospects of nanoparticle-based RNA pesticides.

关键词： dsRNA delivery nanocarrier pest control RNAi efficiency RNA pesticide

Herbivory of sympatric elk and cattle on Lincoln National Forest,south-central New Mexico

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Forest Ecosystems 2015年第4期2卷 314-326页

作者： Heather H.Halbritter Louis C.Bender extension Animal Sciences and Natural Resources New Mexico State University

Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. Herbivory by North American elk and domestic cattle is a contentious management issue throughout western North America, often driving management proposals to decrease cattle and elk numbers based on perceived overutilization of forages. Such observations are often site level rather than landscape, and may confuse ecological sustainability with desired conditions. Methods： We used line transects to document vegetation composition, structure, and grazing and browsing utilization for 4 key habitat types： mountain meadows, aspen, thinned conifer, and burned conifer on Lincoln National Forest, New Mexico, USA. We documented relative habitat use of these types by elk, mule deer, and cattle and modeled relative use on residual grass biomass of mountain meadows and browse utilization of forested types. We determined diets and diet quality of elk and cattle to assess degree of competition. Results： Use of grasses in meadows was below management thresholds, and combined elk, cattle, and deer relative habitat use accounted for 〈 14 % of the variance in residual stubble height of Poa protensis, the most abundant grass. Palatable browse was limited in habitat types （〈 107 ***^-1）, use was generally high, and elk presence was correlated with the majority of browsing. Elk and cattle diets did not significantly overlap （Schoener＇s index 0.54-0.57）; elk fed primarily on deciduous shrubs （34 %-55 % of annual diets） and cattle on grass （72 %-77 %）. Digestibility and crude protein levels of cattle diets and body condition of elk indicated high quality diets for cattle and marginal-good quality diets for elk. Conclusions： At observed stocking levels and densities, cattle and elk were not competing for forage based on diet similarity, nor were key habitat types being used beyond sustainable levels. Low browse availability indicates that opportunity exists to increase for

关键词： Browsing Cattle Carrying capacity Elk Grazing Herbivory Nutrition

Evaluation of yield,stability and adaptability of national winter rapeseed regional trials in the upper Yangtze River region in 2017-2018

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Oil Crop Science 2020年第3期5卷 121-128页

作者： Ze’en Yu Lixia Luo Fang Zhang Meiyan Hong Xiangxiang Zhang Ruixing Guo Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhanChina National Agricultural Technology extension and service Center BeijingChina

Rapeseed variety needs to be tested by regional trial in multiple sites for many years before being applied in market in *** of rapeseed were affected by the interaction of sites and *** of regional trials is very important for guiding rapeseed ***(genotype main effects and genotypeenvironment interaction)biplot was used to evaluate yield,stability,adaptability,representativeness and discrimination of national winter rapeseed trials in the upper reaches of Yangtze River in *** showed that the main effects of genotype(G),environment(E)and genotypeenvironment interaction(GE)were significant(P<0.01)for *** them,E accounted for 46.95%total variation on average,G and GE accounted for 19.34%and 33.71%*** varieties were found with high-yield,excellent stability and adaptability,including‘Yiyou 29’,‘Xiwang 920’,‘Liyouza 108’,‘Nanyou 546’,‘Dadi 195’,‘Jiayou 1’,‘Huayouza 28’and‘Yuhua 2’.Test sites included Nanchong,Mianyang,Wanzhou,Shuangliu and Chengdu in Sichuan Province and Zunyi together with Guiyang in Guizhou Province were selected for their excellent representativeness and *** results would provide theoretical basis for rapeseed breeding.

关键词： National regional trial GGE biplot High yield Yield stability Adaptability Representativeness Discrimination

Age and sex specific timing, frequency, and spatial distribution of horseshoe crab spawning in Delaware Bay:Insights from a large-scale radio telemetry array

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Current Zoology 2010年第5期56卷 563-574页

作者： David R.SMITH Lorne J.BROUSSEAU Mary T. MANDT Michael J.MILLARD USGS Leetown Science Center Cornell University Cooperative extension U.S. Fish and Wildlife service

To study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and archival tags on adult horseshoe crabs prior to their spawning season. We tagged and released 160 females and 60 males in 2004 and 217 females in 2005. The array covered approximately 140 km of shoreline. Recapture rates were 〉70% with multi-year recaptures. We categorized adult age by carapace wear. Older females tended to spawn earlier in the season and more frequently than young females, but those tendencies were more apparent in 2004 when spawning overall occurred earlier than in 2005 when spawning was delayed possibly due to decreased water temperatures. Timing of initial spawning within a year was correlated with water temperature. After adjusting for day of first spring tide, the day of In＇st spawning was 4 days earlier for every 1 degree （℃） rise in mean daily water temperature in May. Seventy nine % of spawning occurred during nighttime high tides. Fifty five % of spawning occurred within 3 d of a spring tide, which was slightly higher than the 47% expected if spawning was uniformly distributed regardless of tidal cycle. Within the same spawning season, males and females were observed spawning or intertidally resting at more than one beach separated by 〉5 kin. Between years, most （77%） did not return to spawn at the same beach. Probability of stranding was strongly age dependent for males and females with older adults experiencing higher stranding rates. Horseshoe crabs staging in the shallow waters east of the channel spawned exclusively along the eastern （N J） shoreline, but those staging west of the channel spawned throughout the bay. Overall, several insights emerged from the use of radio telemetry, which advances our understanding of horseshoe crab ecology and will be useful in conserving the Delaware Bay horseshoe crab population and habita

关键词： Spawning behavior Marine arthropod Xiphosurid Limulus polyphemus Delaware Bay Radio telemetry