نتایج جستجو برای: aphid abundance

تعداد نتایج: 86092  

2013
Daniel L. Jeffries Jason Chapman Helen E. Roy Stuart Humphries Richard Harrington Peter M. J. Brown Lori-J. Lawson Handley

Understanding the characteristics and drivers of dispersal is crucial for predicting population dynamics, particularly in range-shifting species. Studying long-distance dispersal in insects is challenging, but recent advances in entomological radar offer unique insights. We analysed 10 years of radar data collected at Rothamsted Research, U.K., to investigate characteristics (altitude, speed, s...

Journal: :Bangladesh Journal of Zoology 2021

The seasonal dynamics of aphid Aphis craccivora Koch (Hemiptera: Aphididae) on four bean species namely country Lablab purpureus, yard long Vigna sesquipedalis, hyacinth Dolichos lablab and bush Phaseolus vulgaris were studied from September to December 2017 in the experimental field Department Entomology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh. study als...

2013
Zi-hua Zhao Jun-He Liu Da-Han He Xiao-qin Guan Wen-Hui Liu

Insect communities depend on both their local environment and features of the surrounding habitats. Diverse plant communities may enhance the abundance and species diversity of local natural enemies, which is possible due to a higher abundance and species diversity in complex landscapes. This hypothesis was tested using cereal aphid parasitoids and hyper-parasitoids by comparing 18 spring wheat...

Journal: :Environmental entomology 2007
Nicholas P Schmidt Matthew E O'neal Jeremy W Singer

Despite evidence for biological control in North America, outbreaks of the invasive soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), continue to occur on soybean (Glycine max L. Merr.). Our objectives were to determine whether natural enemies delay aphid establishment and limit subsequent population growth and whether biological control can be improved by altering the within-fiel...

2012
Blas Lavandero Pamela Rojas Claudio C. Ramirez Marcela Salazar Peter D.S. Caligari

The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and souther...

Journal: :Biology letters 2009
Jarmo K Holopainen Gürkan Semiz James D Blande

According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a...

Journal: :Proceedings. Biological sciences 2013
S R Weldon M R Strand K M Oliver

Terrestrial arthropods are often infected with heritable bacterial symbionts, which may themselves be infected by bacteriophages. However, what role, if any, bacteriophages play in the regulation and maintenance of insect-bacteria symbioses is largely unknown. Infection of the aphid Acyrthosiphon pisum by the bacterial symbiont Hamiltonella defensa confers protection against parasitoid wasps, b...

2014
Sophie Bouvaine Marie-Line Faure Robert J. Grebenok Spencer T. Behmer Angela E. Douglas

The aphid Myzus persicae displays high mortality on tobacco plants bearing a transgene which results in the accumulation of the ketosteroids cholestan-3-one and cholest-4-en-3-one in the phloem sap. To test whether the ketosteroids are the basis of the plant resistance to the aphids, M. persicae were reared on chemically-defined diets with different steroid contents at 0.1-10 µg ml(-1). Relativ...

2011
Fernando Álvarez-Alfageme Simone von Burg Jörg Romeis

A concern associated with the growing of genetically modified (GM) crops is that they could adversely affect non-target organisms. We assessed the impact of several transgenic powdery mildew-resistant spring wheat lines on insect herbivores. The GM lines carried either the Pm3b gene from hexaploid wheat, which confers race-specific resistance to powdery mildew, or the less specific anti-fungal ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید