Within-plant distribution of Phorodon humuli (Hemiptera: Aphididae) and natural enemies on hops with implications for sampling and management

2017 ◽  
Vol 20 (1) ◽  
pp. 443-450
Author(s):  
Alicia Lorenzana ◽  
Alfonso Hermoso De Mendoza ◽  
M. Victoria Seco ◽  
M. Piedad Campelo ◽  
Pedro A. Casquero
Keyword(s):  
Natural Enemies ◽  
Plant Distribution ◽  
Phorodon Humuli

scholarly journals Within-field distribution of the damson-hop aphid Phorodon humuli (Schrank) (Hemiptera: Aphididae) and natural enemies on hops in Spain

2017 ◽  
Vol 15 (2) ◽  
pp. e1006
Author(s):  
Alicia Lorenzana ◽  
Alfonso Hermoso de Mendoza ◽  
Victoria Seco ◽  
Piedad Campelo ◽  
Pedro A. Casquero
Keyword(s):  
Spatial Distribution ◽  
Wind Speed ◽  
Pest Management ◽  
Field Distribution ◽  
Natural Enemies ◽  
Natural Enemy ◽  
Coccinella Septempunctata ◽  
Population Densities ◽  
Phorodon Humuli ◽  
Sampling Program

A field trial was performed in a hop yard throughout 2002, 2003 and 2004 in order to determine the within-field distribution of Phorodon humuli (Schrank) (Hemiptera: Aphididae) and its natural enemies. The distribution of P. humuli was directly affected by the position of the hop plants in the garden, with significantly higher concentrations of aphids (p=0.0122 in 2002 and p=0.0006 in 2003) observed along the edge. However, in 2004 the plants located on the marginal plots had similar populations to those on the more inner plots. This can be explained by a higher wind speed which made it more difficult to land on edge plants first. The hop aphid’s main natural enemy was Coccinella septempunctata (Coleoptera: Coccinellidae), whose population was greatest where the aphids were most abundant with a significantly greater number of eggs (p=0.0230) and adults (p=0.0245) in 2003. Lacewing eggs were also frequently observed, with a significantly higher population (p=0.0221 in 2003 and p=0.0046 in 2004) where the aphid numbers were high. The number of winged aphids was greatest towards the margins of the garden in 2003. It is argued that the spatial distribution of the hop aphid and its natural enemies could be used to plan a sampling program and to estimate the population densities of these insects for use in integrated pest management programs.

Within-plant distribution of thrips and their predators: effects of cotton variety and developmental stage

1996 ◽  
Vol 86 (6) ◽  
pp. 641-646 ◽  
Author(s):  
Ekrem Atakan ◽  
Moshe Coll ◽  
David Rosen
Keyword(s):  
Developmental Stage ◽  
Natural Enemies ◽  
Spatial Association ◽  
Distribution Patterns ◽  
Thrips Tabaci ◽  
Plant Distribution ◽  
Cotton Variety ◽  
Risk Of Predation ◽  
Sampling Protocols ◽  
Thrips Species

AbstractPlant characteristics often influence the distribution of herbivores and natural enemies. In turn, the degree of their spatial association is likely to influence the ability of natural enemies to control pests. Also, an understanding of pest distribution patterns is important for the development of reliable and cost-effective sampling protocols. In this study, we assessed the effect of cotton variety and developmental stage on the within-plant distribution and degree of spatial overlap between populations of two thrips species and their predators. In the two studied varieties, cv. Pima and Acala, almost all Thrips tabaci Lindeman inhabited the leaves, while Frankliniella occidentalis (Pergande) colonized only the flowers. With respect to the predators, most Chrysoperla carnea (Stephens) were found on the leaves of both varieties, whereas predatory Orius spp. colonized mainly the flowering structures on Pima plants but the leaves on Acala. This variability in prey and predator distribution resulted in a significant and positive correlation between thrips and predator populations on Pima but not on Acala plants. The results also suggest that, overall, thrips are most likely to be preyed upon on squares and to be relatively safe in flowers. An intermediate but relatively high risk of predation apparently occurs on the leaves. The significance of these within-plant distribution patterns for the monitoring of thrips populations is discussed.

Some Curious Facts in Plant Distribution

1896 ◽  
Vol 41 (1065supp) ◽  
pp. 17016-17017
Author(s):  
W. Botting Hemsley
Keyword(s):  
Plant Distribution

Yellow Brazilian Pepper-tree Leaf Galler (suggested common name) Calophya latiforceps Burckhardt (Insecta: Hemiptera: Calophyidae: Calophyinae)

EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
James P. Cuda ◽  
Patricia Prade ◽  
Carey R. Minteer-Killian
Keyword(s):  
Biological Control ◽  
North America ◽  
Natural Enemies ◽  
Host Plants ◽  
Classical Biological Control ◽  
Biological Control Agents ◽  
Pepper Tree ◽  
Brazilian Pepper ◽  
Close Relatives ◽  
Tree Leaf

In the late 1970s, Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae), was targeted for classical biological control in Florida because its invasive properties (see Host Plants) are consistent with escape from natural enemies (Williams 1954), and there are no native Schinus spp. in North America. The lack of native close relatives should minimize the risk of damage to non-target plants from introduced biological control agents (Pemberton 2000). [...]

Comparative Effectiveness Of Seed Treating And Foliar Insecticides Against Sucking Pests Of Cotton And Impact On Their Natural Enemies

2013 ◽  
Vol 38 (1) ◽  
pp. 61-70 ◽  
Author(s):  
SMA Hossain ◽  
MA Baque ◽  
MR Amin
Keyword(s):  
Natural Enemies ◽  
Untreated Control ◽  
Seed Treatment ◽  
Foliar Spray ◽  
Cost Ratio ◽  
Research Station ◽  
Benefit Cost Ratio ◽  
Benefit Cost ◽  
Thrips Population ◽  
Cotton Cultivar

The Imidacloprid insecticide, Gaucho 70 WS at 1.5, 2.5, 3.5, 4.5 and 5.5 g/kg seed was used as seed treatment and monocrotophos 40 WSC at 1120 ml/ha was applied as foliar spray on CB9 cotton cultivar to suppress aphid, whitefly and thrips, and impact on their natural enemies during 2008-2011 at the Regional Cotton Research Station, Dinajpur, Bangladesh. The activity of natural enemies, such as ladybird beetle, lacewing, syrphid, and spider population on the sucking pests attacking cotton cultivar CB9 and yield of cotton were recorded. Imidacloprid significantly reduced aphid, whitefly, and thrips population on cotton crops compared to untreated control or foliar spray of monocrotophos 40 WSC at 1120 ml/ha. Ladybird beetles, lacewings, syrphids, and spiders were abundant in the field but their population decreased in the treated plots compared to untreated control. The CB9 cotton cultivar produced significantly higher yield (1.73 t/ha) with a benefit cost ratio 12.47 when seeds were treated with Imidacloprid at 5.5 g/kg fuzzy seed. This study indicated that Imidacloprid (Gaucho 70 WS) used as a seed treatment may be suggested to the cotton growers for controlling sucking pests. Bangladesh J. Agril. Res. 38(1): 61-70, March 2013 DOI: http://dx.doi.org/10.3329/bjar.v38i1.15190

BIOEFFICACY OF PLANT EXTRACTS AGAINST MUSTARD APHID AND THEIR NATURAL ENEMIES

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
NARENDRA SINGH ◽  
N. S. BHADAURIA ◽  
PRADYUMN SINGH
Keyword(s):  
Plant Extracts ◽  
Natural Enemies ◽  
Untreated Control ◽  
Plant Material ◽  
Aphid Population ◽  
College Of Agriculture ◽  
Mustard Aphid ◽  
Plant Materials

The Bio-efficacy of eleven plant extracts namely viz.Neem Kernel; Rhizome of Ginger; Leaves of Datura, Gajarghas, Harsingar, Oak and Latjeera; Bulb of Garlic and Onion; Flowers of Chrysenthemum and Fruits of Chilli in the concentration of 5 percent and imidacloprid @ 40 g ai/ha was tested against mustard aphid, Lipaphiserysimi and their effect on D. rapae and Coccinellid beetle were tested in the Department of Entomology, College of Agriculture, Gwalior (M.P.). All the tested plant materials and imidacloprid @ 40 g ai/ha were effective significanty in reducing the aphid population over control.The aphid population in treated plots ranged from 7.2 to 40.0 as against 85.4 aphid/twig in untreated control. Among the plant material, three sprays of Neem Kernel were found most effective followed by three sprays of chilli fruits.All the plant extracts were found significantly safer to D. rapae and coccinellid bettle in comparision to insecticide (imidacloprid).

John Lloyd Williams (1854–1945): profile of a Snowdonian botanist

2006 ◽  
Vol 33 (1) ◽  
pp. 1-17
Author(s):  
Dewi Jones
Keyword(s):  
Nineteenth Century ◽  
Plant Physiology ◽  
Marine Algae ◽  
Plant Distribution ◽  
The Arctic ◽  
Late Nineteenth Century ◽  
Major Study ◽  
The Subject ◽  
Late Nineteenth

John Lloyd Williams was an authority on the arctic-alpine flora of Snowdonia during the late nineteenth century when plant collecting was at its height, but unlike other botanists and plant collectors he did not fully pursue the fashionable trend of forming a complete herbarium. His diligent plant-hunting in a comparatively little explored part of Snowdonia led to his discovering a new site for the rare Killarney fern (Trichomanes speciosum), a feat which was considered a major achievement at the time. For most part of the nineteenth century plant distribution, classification and forming herbaria, had been paramount in the learning of botany in Britain resulting in little attention being made to other aspects of the subject. However, towards the end of the century many botanists turned their attention to studying plant physiology, a subject which had advanced significantly in German laboratories. Rivalry between botanists working on similar projects became inevitable in the race to be first in print as Lloyd Williams soon realized when undertaking his major study on the cytology of marine algae.

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