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1.
Every year, the Student Debates Subcommittee (SDS) of the Student Affairs Committee (SAC) for the annual Entomological Society of America (ESA) meeting organizes the Student Debates. This year, the SAC selected topics based on their synergistic effect or ability to ignite exponential positive change when addressed as a whole. For the 2019 Student Debates, the SAC SDS identified these topic areas for teams to debate and unbiased introduction speakers to address: 1) how to better communicate science to engage the public, particularly in the area of integrated pest management (IPM), 2) the influential impacts of climate change on agriculturally and medically relevant insect pests, and 3) sustainable agriculture techniques that promote the use of IPM to promote food security. Three unbiased introduction speakers gave a foundation for our audience to understand each debate topic, while each of six debate teams provided a strong case to support their stance or perspective on a topic. Debate teams submitted for a competitive spot for the annual ESA Student Debates and trained for the better part of a year to showcase their talents in presenting logical arguments for a particular topic. Both the debate teams and unbiased introduction speakers provided their insight toward a better understanding of the complexities of each topic and established a foundation to delve further into the topics of science advocacy and communication, climate change, and the many facets of integrated pest management.  相似文献   

2.
Abstract The objective of the study was to describe the annual and seasonal production of live biomass of six plant species or communities of the uplands of the UK –Calluna vulgaris, Vaccinium myrtillus, Nardus stricta, Molinia caerulea, Eriophorum vaginatum and Agrostis–Festuca grassland. The species or communities are important for the management of the uplands to meet both biodiversity and agriculture objectives. The annual and seasonal production of live biomass was determined for sites within six regions of England and Wales in 1995, 1996 and 1997. The six regions were North‐east England, North‐west England, North Pennines, South Pennines, South‐west England and Wales. In each region, the Institute of Terrestrial Ecology's Land Classification Scheme was used to select three or four 2 km × 2 km squares that contained a mosaic of C. vulgaris and upland grassland plant species. Uniform plots of 1 ha were selected from each 2 km × 2 km square, within which three measurements were made on each sampling occasion. Biomass of each species or community was measured within 1·0 × 0·5‐m quadrats using the same standard procedures. Measurements of annual production of current season's shoots of the pioneer, building, mature and degenerate phases of C. vulgaris and of V. myrtillus were made in October, and of the annual production of live biomass of N. stricta, M. caerulea and E. vaginatum in August. A simulated grazing regime was imposed for the Agrostis–Festuca grassland with cuts being made to a height of 4 cm at 8‐week intervals. The annual production of live biomass produced was estimated as the sum of four harvests taken during the growing season. Seasonal measurements of the amount of live biomass of all the species were also made in April, June, August and October. For C. vulgaris, there were significant (P = 0·05) differences between the pioneer, building, mature and degenerate phases in the annual production of current season's shoots, with greater amounts being produced by the phases of greater age and with higher biomass. There were significant year (P < 0·05) and region (P < 0·05) effects, with the lowest production in 1995 and in the South‐west of England. The values were higher than those observed in previous studies in Scotland, and these were interpreted as being associated with a longer growing season rather than higher summer temperatures. There was no difference between years and regions in the annual production of V. myrtillus. For the grass species, there were small differences in annual production of live biomass between years and regions. However, the annual production of live biomass of N. stricta was significantly (P < 0·01) lower in 1995 than in 1996 and 1997 and significantly (P < 0·001) lower in the South Pennines region than elsewhere. The effect of a range of weather and other environmental variables on the annual production of live biomass of each species of grass was explored, but they provided only a limited insight into the reasons for the observed differences and were found to be of limited value as predictors.  相似文献   

3.
We statistically discuss the possible ways to classify rice varieties using canopy bi-directional reflectance factor (BRF) data. Fourteen varieties of rice (Oryza sativa L.) were grown in an experimental paddy field where environmental conditions such as soil, nutrients, water supply, and local climate were homogeneous. Spectral reflectance of each of the rice varieties was measured at nadir and at off-nadir angles of 45°, 30°, 15°, –15°, –30°, and –45° on both the principal and perpendicular planes at intervals of 1 nm from 400 to 850 nm. The reflectances in green (550–560 nm), red (675–685 nm), and near infrared (745–749 nm) bands at every measuring angle were computed for each rice variety. As a result of unpaired Student t-tests, the number of pairs of rice varieties that can be statistically distinguished using BRF data was larger than the number that can be distinguished using just the spectral reflectance data at the nadir angle. The difference in BRF among rice varieties was statistically significant.  相似文献   

4.
Potato Breeding: a Challenge, as ever!   总被引:1,自引:0,他引:1  
E. Bonnel 《Potato Research》2008,51(3-4):327-332
Breeding efforts for the potato sector are faced with the classical questions “What to breed?” and “How to breed?”. The answers to these questions are very diverse and challenged. Until recently these two questions were unrelated. With the increase in scientific knowledge and the public debate on modern tools, these questions have become intertwined. The “What to breed?” question has changed: breeders nowadays have to breed for wider adaptation to increasingly stressful environments with an increase in focus on quality demands by an increasingly complex and diverse food processing industry and distribution networks. The “How to breed?” question has changed also: public funding is increasingly scarce for agricultural research in general and for research on the biotechnology, molecular genetics and molecular biology of potato in particular. Young scientists also move away from the potato crop. However, the complexity of the inheritance and of the physiology of potato combined with the diverse stress to which this crop is exposed, requires large investments to be able to use modern scientific tools. Such huge investments are mostly too costly for the traditional dominant players in potato breeding despite the mergers that have taken place. The only solution for this is to link up with and stimulate international networks and use the modern information technology to obtain access to valuable scientific information. The technology used also determines public acceptance of the product, thus making the “What to breed?” and “How to breed?” questions interwoven. Another important issue that has affected the environment for potato breeders is the fact that breeders have not been defending their rights very well. Counterfeited multiplication of protected varieties has become commercially more important whereas new conventions and treaties have made the exchange and use of germplasm much more complicated. Modern potato breeders, while maintaining their classical skills, have to be prepared to be more involved in basic science, more receptive to public concerns and more proactive to protect their rights.  相似文献   

5.
To identify the susceptibility of long-horned grasshoppers to entomopathogenic fungi, the effect of infection with the fungi Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae) on food consumption by Uvarovistia zebra (Uvarov) (Orthoptera: Tettigoniidae) was investigated. Preliminary results showed that both fungi had a negative effect on food consumption of the insects. For both fungi a significant reduction of food consumption and faeces production by insects were observed between the highest spore concentration (5 × 106 spores/ml) and other treatments. Compared with control insects, the insects treated with 5 × 106 spores/ml of B. bassiana and M. anisopliae showed 60 and 63% reduction in mean food consumption/insect, respectively. The corrected cumulative percent mortality of the insects treated with the highest concentration of B. bassiana and M. anisopliae were 57.7 and 55.5%, respectively. This was the first account of these entomopathogenic fungi being used against a species from this family, therefore based on the results obtained from this research, it could be said that the fungi have pathogenicity effect on U. zebra as a long-horned grasshopper.  相似文献   

6.
Application of slurry in spring to grassland in north‐west Europe increases the efficiency of nitrogen recovery compared with the application in summer. In Ireland, however, more than 0·50 of slurry is applied in the summer. The splash‐plate method of application, most commonly used in Ireland, can make application in spring difficult because of the risk of contamination of grass with slurry, affecting subsequent silage quality and grazing preferences. This study evaluated the potential of low‐emission spreading methods to increase the opportunity for spring application of slurry using an agro‐meteorological modelling approach. Weather data from two weather stations were combined with data on grass growth from two nearby sites. Using three soil‐drainage classes (well, moderate and poor), each with a typical regime of grassland management, a database of soil moisture deficits, drainage, patterns of grazing and cover of grass herbage was developed for three hypothetical management systems, one for each soil drainage class, at each site. Simulations of four slurry application methods [splash‐plate (SP), band‐spreader (BS), trailing‐shoe (TS) and shallow‐injection (SI)], subject to a series of constraints, were compared over an 8‐year period (1998–2005) in order to determine the number of days during the period from 1 January to approximately 10 May of each year, when it was considered that grassland was suitable for application of slurry. These constraints were: (i) restrictions on spreading imposed by current legislation in Ireland; (ii) the period before occurrence of drainage or overland flow; (iii) soil trafficability; (iv) the time‐lag before a subsequent grazing or harvest event; and (v) herbage mass of the pasture. On well and moderately drained soils, the model predicted that the highest number of days available for slurry spreading was found for the TS method followed by the BS, SI and SP methods. There was no difference between application methods in the number of available days on poorly drained soils.  相似文献   

7.
To properly define ecoregions, specific criteria such as geology, climate, or species composition (e.g., the presence of endemic species) must be taken into account to understand distribution patterns and resolve ecological biogeography questions. Since the studies on insects in Baja California are scarce, and no fine-scale ecoregions based on the region’s entomofauna is available, this study was designed to test whether the ecoregions based on vegetation can be used for insects, such as Calliphoridae. Nine collecting sites distributed along five ecoregions were selected, between latitudes 29.6° and 32.0°N. In each site, three baited traps were used to collect blow flies from August 2017 to June 2019 during summer, winter, and spring. A total of 30,307 individuals of blow flies distributed in six genera and 13 species were collected. The most abundant species were Cochliomyia macellaria (Fabricius), Phormia regina (Meigen), and Chrysomya rufifacies (Macquart). The composition of the Calliphoridae community was different between the localities and three general groups have been distinguished, based on the species composition similarity (ANOSIM) results: Gulf-Desert, Mountains, and Pacific-Center. The vegetation-based ecoregions only reflect the blow fly species’ distributions to a certain extent, meaning that care must be taken when undertaking ecological biogeographical studies using regionalization based on organisms other than the focal taxa because vegetation does not always reflect fauna species composition.  相似文献   

8.
Yield trials without fungicides or insecticides were conducted four consecutive years (2007–10) at the University of Georgia, Coastal Plain Experiment Station, Tifton Campus to evaluate for peanut (Arachis hypogaea L.) pest resistance. The most endemic diseases in the southeast U.S. are tomato spotted wilt (TSW) caused by Tomato spotted wilt virus, white mold (WM) caused by Sclerotium rolfsii Sacc, and both early and late leaf spot caused by Cercospora arachidicola Hori and Cercosporidium personatum (Berk & Curt.) Deighton, respectively. The most endemic insects are tobacco thrips (Frankliniella fusca Hinds) and potato leafhopper (Empoasca fabae Harris). Results from these replicated field tests showed significant differences (P ≤ 0.05) among advanced Georgia breeding lines and cultivars. Three Georgia cultivars ‘Georgia-01R’, ‘Georgia-05E’, and ‘Georgia-10T’ consistently produced among the best yields with high levels of resistance to TSW, white mold, leafhoppers, and leaf spot each year. Georgia-01R is a multiple-pest-resistant, runner-type cultivar with late maturity; whereas, Georgia-05E is a multiple-pest-resistant, virginia-type cultivar with medium-late maturity. Georgia-10T is a new runner-type cultivar with high level of TSWV and white mold resistance and late-maturity, similar to Georgia-01R, one of its parents. However, Georgia-10T does not appear to have the high level of leaf spot and leafhopper resistance as Georgia-01R, but it still had high yields in the absence of fungicides or insecticides.  相似文献   

9.
The objective of this special issue is to highlight the current state of research in the field of insects as food and feed, but also other aspects on the exploitation of insect farming. In this editorial, we make a short introduction of the topic of the special issue, briefly present the contributions that are collected in it and offer some thoughts on the future research priorities and challenges that should be addressed. Regarding insect farming, there are additional applications, such as fertilizer, health-promoting products, and cosmetics, that can be produced and utilized, that go far beyond food and feed production.  相似文献   

10.
A series of experiments examined the removal of insects, mites and insecticide residues from grain passed through a grain-cleaner comprising a de-awner and aspiration chamber and a sequence of inclined, reciprocating sieves. The cleaner was evaluated for its ability to remove adult insects from 1 kg grain samples by comparing the removal of 30 and 200 insects of each of Oryzaephilus surinamensis (L.), Sitophilus granarius (L.) and Cryptolestes ferrugineus (Stephens) using 1.0 and 2.0 mm sieves. Pest-free samples were reliably produced using a 2.0 mm sieve at the cost of a loss of about 4.5% in weight of dockage or cleanings removed. Cleaning produced a 90% reduction in live mite numbers but populations partially recovered afterwards, although still reaching only one-fifth of the uncleaned controls. After cleaning, 90% alive and dead Glycyphagus destructor were recovered from the cleanings but only 30% of Acarus siro were in the cleanings with a further 10% in the prime grain, leaving about 60% unaccounted for. Removal of about 1.6% dockage or cleanings resulted in a loss of approximately 20% of pesticide in half of the tests using etrimfos and pirimiphos-methyl emulsifiable concentrates and dust at 2 and 4 mg/kg.  相似文献   

11.
12.
Mediterranean dehesas are an archetypal example of high nature value farmland in Europe. To better understand the interactions between trees and grasslands in the conservation and management of the dehesa, we measured, over 3 years, the contribution of scattered trees to the diversity and biomass dry‐matter (DM) yield of the herb layer and the relationship between the herb layer (biomass and diversity interaction) and the trees. The study was based on 135 subplots representing four aspects and three distances from fifteen trees selected randomly in a plot within a dehesa in central Spain. The specific questions were the following: (i) To what extent do trees affect biomass of the herbaceous layer? (ii) What is the relationship between herbaceous layer biomass and species diversity under the influence of trees? and (iii) What are the effects of trees and small‐scale topography on the herbaceous diversity? Results differed between years depending on water availability. Legume and forb DM yields were highest at the edge of the tree crown and beyond the canopy. Species richness was positively related to legume DM yield, and both were higher at the bottom of the hillside, especially in dry conditions. Given the importance of tree influence on the biomass and diversity of grasslands, maintaining proper agroforestry management practices for trees and grasslands is important for conserving dehesa diversity and productivity under the conditions of high climatic and soil variability in Mediterranean dehesas.  相似文献   

13.
A resting plate meter was tested in the laboratory and on a field site to determine its effectiveness for estimating peak herbage mass on semi-arid grasslands. In laboratory tests, data from the plate meter closely predicted the herbage mass of four perennial bunch grasses (thirteen of sixteen tests with r 2 ≥ 0·90) but the closeness of the prediction varied with the pressure of the plate. Field tests took place on a southern Arizona, USA semi-arid grassland in 2005, 2006, 2007 and 2008. Twenty teams of two or three people sampled the site; five teams in each year measured eight to thirteen plate heights and clipped the vegetation beneath. Consistent with a need for yearly calibration, a significantly different ( P  <   0·05) linear relationship was detected between 3 of the 4 years which was associated with differences in average herbage mass of dry matter (DM) (1525 kg ha−1 for 2005, 2093 kg ha−1 for 2006, 1338 kg ha−1 for 2007 and 1370 kg ha−1 for 2008). Plate height poorly predicted herbage mass within years ( r 2  = 0·21, 0·51, 0·49 and 0·41 respectively) with plate heights explaining half or less of the variability in field herbage mass and having a mean prediction error of 466 kg DM ha−1. The plate meter technique had limited potential for estimating peak herbage mass in semi-arid grasslands.  相似文献   

14.
Risk and cost estimates, calculated using a weather‐driven farm simulation model, were used to evaluate the impact of different haymaking strategies in dryland cow‐calf systems such as those in the Salado region of Argentina. Based on a 100‐ha farm, each strategy was simulated using twenty sequences of 50 years of random weather. A risk‐efficiency methodology was used, using calf live weight sold and considering the economic value of the live weight produced per year minus the cost of haymaking, as a simple measure of profit. The analysis highlighted both production and risk advantages in using hay, especially when a flexible hay management approach was implemented, although some haymaking strategies performed worse than not using hay. When calf live weight sold was considered alone, the risk‐efficient set included strategies with large proportions of the areas being harvested (0.42–1.05; paddocks could be cut more that once a year in some of the strategies) and high proportions of hay not being used. The amount of hay for maximizing risk efficiency for profit was notably lower than that for maximizing cattle production. When haymaking costs were included, the proportion of area harvested for risk‐efficient profit ranged from 0.28 to 0.52, depending on the target stocking rate.  相似文献   

15.
Alpha-amylase inhibitors are attractive candidates for the control of seed weevils as these insects are highly dependent on starch as an energy source. For weevil control, alpha-amylase inhibitors and their genes could be used to genetically engineer weevil resistant seeds. Thirty genes encoding dimeric alpha-amylase inhibitors were isolated from Triticum aestivum L. ‘Chinese Spring’ and characterized by nucleotide and amino acid sequence analysis. Eleven representative alpha-amylase inhibitor genes were identified, and the deduced amino acid sequences of these genes were of high coherence (95.1%). These inhibitors and others obtained from the wheat EST database were clustered into three groups, the genes from ‘Chinese Spring’ were present in each group. Specific primer sets were designed for each group, based on the SNPs of these genes, and the chromosome locations of each group of inhibitor genes investigated by amplification of the ‘Chinese Spring’ ditelosomic lines. There were two and one groups of inhibitor genes on chromosomes 3BS and 3DS, respectively, whereas no group of inhibitor genes was found on chromosome 3AS. Thus, the primer set for each group of inhibitor genes was genome allele-specific. The two known inhibitors, 0.53 and 0.19, were located on chromosomes 3BS and 3DS, respectively. The validity of the three genome allele-specific primer sets was confirmed by amplifications in 15 accessions of Triticum urartu, Triticum monococcum, Aegilops tauschii and Triticum dicoccoides. These results gave further support at the molecular level, that the 24 kDa dimeric alpha-amylase inhibitors in cultivated wheat are encoded by a multigene family.  相似文献   

16.
A bifunctional electric field screen was proposed to physically exclude insect pests from warehouses. The screen consists of insulated iron wires (ICW) arranged in parallel and two earthed conductor nets placed on both sides of the ICW. A negative charge (0.1-8.0 kV) was applied to the insulated wires with a voltage generator to polarize an insulator sleeve used to cover the wire, negatively on the outer surface and positively on the inner conductor wire surface of the sleeve. The negative surface charge of the ICW caused an electrostatic induction in the earthed nets and an opposite charge on the net surfaces facing the ICW. An electric field formed in a space between the ICW and the earthed net, and the field strength increased in direct proportion to increasing voltages applied to the ICW. Adults of the test insects (cigarette beetle (Lasioderma serricorne) and vinegar fly (Drosophila melanogaster)) reaching the outer surface of the earthed net were deterred from entering the inside of the charged screen, whereas all insects immediately passed through the screen when the ICW was not charged. This avoidance was directly proportional to the increase in the voltage. In addition, the capability of the screen to capture insects that enter inside the screen was proven by introducing insects into the space between the ICW and the earthed net. Strong capture was observed when the ICW was negatively charged with more than 4.1 kV, under which conditions a short-term electric current (peaking at 0.3-0.6 μA, for 3 min) occurred transiently. This electric current was due to the release of electricity from the insects, giving a net overall positive charge to the insects, which therefore were attracted more strongly to the negatively charged ICW. A test using an attractant-set chamber showed that the insects were completely prevented from passing through the charged screen, in contrast to a rapid transfer of all insects when the screen was not charged. Thus, the present results show that the described screen is a promising physical tool for controlling insect pests in warehouses.  相似文献   

17.
Grass silage made in late May from S24 perennial ryegrass was offered ad libitum to eight Ayshire cows in a 16-week feeding experiment. The silage had a DM concentration of 244 g kg−1, contained 163 g crude protein (kg DM)−1 with a ruminal degradability of 0.77 and had an in vitro DOMD concentration of 678 g kg−1. In addition, four concentrates each containing 167 g soya-bean meal kg−1 were consumed at a mean daily rate of 6.43 kg DM per cow. The soya-bean meal was either untreated, or 'protected' by formalin and mixed in the following proportions, 100:0; 66:34; 34:66; and 0:100 respectively, in the four concentrates. The daily intakes of silage DM were not significantly different on the four treatments and averaged 90 kg DM per cow, giving a mean total daily DM intake of 32.4 g kg−1 live weight. The milk yields were not significantly different on the four treatments and averaged 23.9 kg −1 The treatments had small and non-significant effects on milk composition and live weight. It is concluded that with a high-digestibility, well-preserved grass silage of satisfactory protein content the inclusion of 'protected' protein in the supplementary concentrate had no beneficial effects on milk production.  相似文献   

18.
Grain yields of a soft white winter wheat cultivar, cv. Ionia, susceptible to cereal leaf beetle (Oulema melanopus (L.)), were determined when the crop was subjected to four controlled infestation levels of the beetle in caged plots over a 3-year period in Michigan. Although identical infestation procedures and insect numbers were used each year, the intensity of larval infestation and feeding damage varied with the year. Significant (P < 0·01) grain losses occurred in plots that had at least 9·0 larvae per stem. The greatest yield loss was 45% and occurred with 15 larvae per stem and 85% feeding damage. Beetle damage had a greater effect on kernel weight than on the other yield components. Although economic thresholds should be conservative to allow for environmental variations, it appears that soft white winter wheat can often withstand beetle infestation levels greater than the current economic threshold of three or more eggs and largae per stem before the boot stage or one or more large larvae per flag leaf during heading.  相似文献   

19.
为了有效防控木薯地下害虫,笔者就木薯主要地下害虫蛴螬、蔗根锯天牛的发生规律与防控技术进行了研究。结果表明,蛴螬发生一代至少1年,成虫在6~8月雨后羽化出土,高温干旱下,坡地、沙质地及木薯连作地、甘蔗轮作地及花生间套作地受害较重;蔗根锯天牛2~3年发生一代,成虫在4~6月雨后羽化出土,高温干旱下,坡地、沙质地及木薯连作地、甘蔗轮作地受害较重;在种植前选用环保型杀虫剂48%乐斯本乳油 1 000倍液和1.8%阿维菌素乳油2 000倍液混合液浸泡种茎5~10 min后种植效果最好,可显著提高出苗率、降低虫害率和提高产量;土坑对金龟子和蔗根锯天牛也具有良好的诱杀效果;“扫虫光”不仅对蔗根锯天牛、蛴螬等木薯主要地下害虫具有良好的防治效果,而且可以促进木薯生长,显著提高鲜薯产量;以种茎药剂处理、土壤药剂处理、土坑诱杀和合理轮作为核心的木薯地下害虫环境友好综合防控效果十分显著,综合防控区平均虫害率由对照的45.6%显著下降到4.2%,产量由对照的16 920 kg/hm2显著提高到49 960 kg/hm2。上述结果为可持续防控木薯害虫的发生与危害提供了理论与技术支撑。  相似文献   

20.
Four new chromones, phomochromenones D–G (1–4), along with four known analogues, diaporchromone A (5), diaporchromanone C (6), diaporchromanone D (7), and phomochromenone C (8), were isolated from the culture of Phomopsis asparagi DHS-48 from Chinese mangrove Rhizophora mangle. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. The absolute configurations of 1 and 4 were assigned on the basis of experimental and calculated electronic circular dichroism (ECD) data, and those of enantiomers 2 and 3 were determined by a modified Mosher’s method and basic hydrolysis. To the best of our knowledge, phomochromenones D–F (1–4) possessing a 3-substituted-chroman-4-one skeleton are rarely found in natural sources. Diaporchromone A (5) showed moderate to weak immunosuppressive activity against T and/or B lymphocyte cells with IC50 of 34 μM and 117 μM.  相似文献   

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