scholarly journals Bee communities in canola are affected by landscape context and farm management

2021 ◽  
Author(s):  
Rachel L Olsson ◽  
Vera W Pfeiffer ◽  
Benjamin W Lee ◽  
David Crowder

Bees are key pollinators that promote greater yield and seed quality of oilseed crops such as canola. Canola acreage has increased over 1,000% in the past decade in the Pacific Northwest USA, providing a major pulse of sugar-rich nectar and pollen resources that may affect bee health and community structure. However, because canola does not require insect pollination for seed production, few studies have examined the biodiversity of pollinators taking advantage of these resources, or the floral traits of canola that affect pollinators across variable landscapes. Here, we conducted pollinator surveys at canola farms across the inland Northwest region of the USA. We surveyed bee biodiversity and abundance, and assessed how these metrics correlated with landscape context, canola production practices, and floral traits of various canola varieties. We found that bee communities differed between sites and across growing seasons, with sweat bees more abundant later in the season, and mining bees more abundant earlier in the season. We also found that bees were more abundant overall on farms with less floral nectar and with less developed landscape surrounding the sampling area. Bee diversity was greater in spring canola than winter canola, and floral traits were also correlated with differing bee community diversity. This research provides important information for canola growers and land managers and offers a framework for future research in pollinator management in the inland Northwest.

2011 ◽  
Vol 6 (3) ◽  
pp. 82
Author(s):  
Genevieve C. Gore

Objective – To survey middle managers’ beliefs regarding their participation in shared leadership and their libraries’ practices of shared leadership. Design – Cross-sectional survey. Setting – Twenty-two academic libraries within four-year public master’s level institutions in the Pacific Northwest of the United States. Subjects – A total of 115 middle managers were invited to participate; 77 completed the survey for a response rate of 66.9%. Methods – Selected middle managers were contacted by email a total of five times and were invited to complete a Web-based survey composed of three sections. The first section contained 10 statements for rating shared leadership within their own institutions, which they were asked to rate on an eight-point Likert scale from 1 (strongly agree) to 7 (strongly disagree), with 8 as an option for no opinion. The second section used the same scale to rate their levels of agreement with conceptual definitions of shared leadership from Jackson’s Framework. Jackson’s Framework consists of four components for ascertaining levels of shared leadership from both managerial and staff perspectives: accountability, equity, partnership and ownership. The third section invited subjects to provide their own definition of shared leadership. A three-part pretest served to validate the survey instrument. Mean scores were calculated for each statement. Main Results – In the first section, there was the highest overall level of agreement (1.52) with the statement “I am accountable for the decisions within the scope of my responsibility” followed by “I share information with the senior library administration” (1.71). There was the lowest overall level of agreement (3.65) with the statement that “Ideas presented at all levels of staff in the library are equally considered.” In the second section, respondents’ mean scores for Jackson’s definitions of four concepts of shared leadership were 2.62 for ownership, 2.68 for both partnership and equity, and 2.77 for accountability. In the third section, respondents most often linked their definitions of shared leadership with communication, learning and collaboration. Conclusion – Examining middle managers’ perceptions of shared leadership may help us understand organizational trends and capacity for leadership within libraries. Future research could examine shared leadership at levels below middle management as well as the relationship between accountability and shared leadership throughout the organization.


2016 ◽  
Vol 46 (10) ◽  
pp. 1695-1700
Author(s):  
Carlos André Bahry ◽  
Paulo Dejalma Zimmer

ABSTRACT: Evaluation of differential candidate gene expression in contrasting soybean seeds is an auxiliary tool in the partial elucidation of processes involved in seeds formation, as well as it contributes to the generation of new information that can be used in future research or in the development of r genetic superior constitutions. The aim of this study was to evaluate the expression of two candidate genes, SBP and leginsulin genes, possibly involved in seed quality, in contrasting coats of four soybean genotypes. Two cultivars of yellow soybeans were used, BMX Potência RR and CD 202, and two lines of black soybean, TP and IAC. Gene expression was evaluated using qPCR in seven stages of development from seed coats for four genotypes, at 25, 30, 35, 40, 45, 50, and 55 days after anthesis. The design was completely randomized, with three replications. Data were subjected to analysis of variance and means compared by Tukey's test at 5% probability. SBP and leginsulin gene have higher expression in the early phases of development from seed coats of BMX Potência RR cultivar, followed by the IAC line. These genotypes are therefore of interest for further research involving these genes.


2019 ◽  
Vol 22 (1) ◽  
pp. 1-7
Author(s):  
B Nessa ◽  
SS Dipti ◽  
MU Salam ◽  
AHMM Haque ◽  
JK Biswas ◽  
...  

Rice false smut (RFSm) is a disease of interest globally and in Bangladesh. Its occurrence and spread have drawn attention since 2010 in the country. While many reports are available on the yield loss from the disease, little is known of its effect on grain quality. Besides, there has been no information on how RFSm affects the seed quality with respect to germination. This study attempted evaluation of seed germination and grain quality of rice as affected by false smut disease. Three years’ study provided strong indication of inferior milling outturn and head rice yield in RFSm contaminated seeds. Results further revealed reduced amylose content and increased protein content in the contaminated seeds. Tendency in reduced seed germination, and less cooking time was observed in RFSm contaminated seeds. Future research is suggested to fully understand those causations. Bangladesh Rice j. 2018, 22(1): 1-7


1991 ◽  
Vol 48 (S1) ◽  
pp. 124-133 ◽  
Author(s):  
Robin S. Waples

The potential for genetic interactions between hatchery and wild populations of salmonids in northwestern North America has increased considerably in recent decades. Efforts to mitigate severe losses to many wild stocks caused by overfishing, destruction of habitat, and blockage of migratory routes have focussed on boosting artificial production in public hatcheries. Opportunities for genetic interactions between hatchery and wild fish will increase if efforts to supplement wild production with hatchery-reared fish continue. Concerns center on three issues: (1) direct genetic effects (caused by hybridization and introgression); (2) indirect genetic effects (principally due to altered selection regimes or reductions in population size caused by competition, predation, disease, or other factors); and (3) genetic changes to hatchery stocks (through selection, drift, or stock transfers), which magnify the consequences of hybridization with wild fish. Strategies for minimizing these genetic risks and monitoring the consequences of various management options are discussed, and some important areas for future research are identified.


Zootaxa ◽  
2021 ◽  
Vol 4999 (2) ◽  
Author(s):  
JOSEPH FORTIER

Aleiodes Wesmael is a large cosmopolitan genus of endoparasitoid wasps that is evidently especially speciose in the Western Hemisphere based on numbers of described species. As with most diverse insect groups, relatively little is known about Aleiodes species diversity and biology. Here I summarize what is known about Aleiodes diversity in Washington State and contiguous Inland Northwest states and province, and I report three new species recently collected by malaise trap sampling for Aleiodes in Okanogan County, WA: Aleiodes khalafi, Aleiodes okanoganensis, and Aleiodes quasiburrus. Given the number of new species (three) and first records of previously described species (two) in Washington elucidated by this study, there is evidently much work to do to reach a fair estimate of Aleiodes species diversity in the Inland Pacific Northwest.


2016 ◽  
Vol 16 ◽  
pp. 213-224
Author(s):  
K.N. Tozer ◽  
G.B. Douglas

Steep, non-cultivable hill country below 1000 m comprises about 40% of New Zealand's land surface and is known as "hill country". It is used predominantly for mixed livestock farming, and makes a large contribution to the national economy. Recently there has been renewed interest by industry and government in germplasm introduction through pasture establishment to increase forage supply in these difficult environments. In this review, establishment is defined as development of a sown pasture species to a stage where it is able to reseed. The aim of this review was to determine the effect of key factors associated with pre-sowing management, sowing, and post-sowing management on establishment, including: site selection, herbicides, the role of litter, grazing management, burning, weed and pest control, fallow, fertiliser, species selection, seed quality, sowing time, sowing method, sowing rate, seed inoculation, coating and pelleting, natural reseeding and dissemination of seeds by animals. Over 120 studies were reviewed. A secondary aim was to highlight directions for future research. Keywords: establishment success, sowing, pasture renewal, oversowing


Author(s):  
Gema Alama-Bermejo ◽  
Pavla Bartošová-Sojková ◽  
Stephen D. Atkinson ◽  
Astrid S. Holzer ◽  
Jerri L. Bartholomew

Proteases and their inhibitors play critical roles in host-parasite interactions and in the outcomes of infections. Ceratonova shasta is a myxozoan pathogen that causes enteronecrosis in economically important salmonids from the Pacific Northwest of North America. This cnidarian parasite has host-specific genotypes with varying virulence, making it a powerful system to decipher virulence mechanisms in myxozoans. Using C. shasta genome and transcriptome, we identified four proteases of different catalytic types: cathepsin D (aspartic), cathepsin L and Z-like (cysteine) and aminopeptidase-N (metallo); and a stefin (cysteine protease inhibitor), which implied involvement in virulence and hence represent target molecules for the development of therapeutic strategies. We characterized, annotated and modelled their 3D protein structure using bioinformatics and computational tools. We quantified their expression in C. shasta genotype 0 (low virulence, no mortality) and IIR (high virulence and mortality) in rainbow trout Oncorhynchus mykiss, to demonstrate that there are major differences between the genotypes during infection and parasite development. High proliferation of genotype IIR was associated with high expression of the cathepsin D and the stefin, likely correlated with high nutrient demands and to regulate cell metabolism, with upregulation preceding massive proliferation and systemic dispersion. In contrast, upregulation of the cathepsin L and Z-like cysteine proteases may have roles in host immune evasion in genotype 0 infections, which are associated with low proliferation, low inflammation and non-destructive development. In contrast to the other proteases, C. shasta aminopeptidase-N appears to have a prominent role in nematocyst formation in both genotypes, but only during sporogenesis. Homology searches of C. shasta proteases against other myxozoan transcriptomes revealed a high abundance of cathepsin L and aminopeptidase homologs suggesting common gene requirements across species. Our study identified molecules of potential therapeutic significance for aquaculture and serves as a baseline for future research aimed at functional characterisation of these targets.


2000 ◽  
Vol 51 (5) ◽  
pp. 649 ◽  
Author(s):  
S. J. Yeates ◽  
R. J. Lawn ◽  
S. W. Adkins

To demonstrate a model to simulate the risk of weather damage of mungbean, application studies were undertaken using 27 years of climatic data collected at Katherine, Northern Territory, Australia. In terms of the risk of weather damage, the transition from high risk to low risk occurred after mid-February but before 20 March. High quality seed could be expected in 70% of seasons for a crop that matured after 20 March. For planting dates prior to 25 January, the chance of producing premium quality seed was enhanced to 40–70% of seasons by sowing a cultivar that matured 2 weeks later and by harvesting promptly (4 days after maturity). There was no benefit from later maturity or harvest promptness where sowing was made after 25 January, because maturity occurred after the wet season was complete. In contrast, yield was optimised at early January sowing dates. Calculating gross margins by combining yield and weather damage simulations identified an optimum sowing date between the optimum for yield and seed quality. It was shown that later maturity combined with photoperiod sensitivity increased the sowing window from 10 to 29 days compared with a short duration variety that was insensitive to photoperiod. The relative merits of modelling and field experimentation in assessing the cropping potential for mungbean in a new region are discussed. The need to be able to simulate the yield of the second flush of flowers was acknowledged as a future research requirement.


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