Effects of seed treatments and storage duration on Myzus persicae (Hemiptera: Aphididae) and amaranth fresh leaf yield.

The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), is a key insect pest of amaranth in East Africa. Pest management has been restricted to indiscriminate application of insecticides to foliage. Applying systemic insecticides to seeds has been shown to manage aphid infestations in other crop systems.

Repellency Potential of Tomato Herbivore-Induced Volatiles Against the Greenhouse Whitefly (Trialeurodes vaporariorum) (Hemiptera: Aleyrodidae).

The greenhouse whitefly, Trialeurode vaporariorum, is among the key pests of tomato (Solanum lycopersicum) in sub-Saharan Africa with Tuta absoluta, spider mite, thrips, and fruitworms. To understand the interaction between the pest and the plant's herbivory-induced plant volatile (HIPVs), we investigated the repellency of four tomato cultivars (Kilele F1, Assila F1, Red Beauty F1, and Nemonneta F1) upon infestation by Trialeurode vaporariorum. We analyzed the behavioral response of T.

Identification of Repellents from Four Non-Host Asteraceae Plants for the Root Knot Nematode, .

Olfactory cues guide plant parasitic nematodes (PPNs) to their host plants. We tested the hypothesis that non-host plant root volatiles repel PPNs. To achieve this, we compared the olfactory responses of infective juveniles (J2s) of the PPN to four non-host Asteraceae plants, namely, black-jack (), pyrethrum (), marigold (), and sweet wormwood (), traditionally used in sub-Saharan Africa for the management of PPNs.

Resistance of Amaranthus Spp. to the Green Peach Aphid (Hemiptera: Aphididae).

The green peach aphid [Myzus persicae (Sulzer)] is an important pest of amaranth grown for leaf consumption (i.e., leafy amaranth) in the tropics.

Elicitation of Differential Responses in the Root-Knot Nematode Meloidogyne incognita to Tomato Root Exudate Cytokinin, Flavonoids, and Alkaloids.

Root exudates of plants mediate interactions with a variety of organisms in the rhizosphere, including root-knot nematodes (RKNs, Meloidogyne spp.) We investigated the responses of the motile stage second-stage juveniles (J2s) of Meloidogyne incognita to non-volatile components identified in the root exudate of tomato. Using stylet thrusting, chemotaxis assays, and chemical analysis, we identified specific metabolites in the root exudate that attract and repel J2s.

Cucumber and Tomato Volatiles: Influence on Attraction in the Melon Fly Zeugodacus cucurbitate (Diptera: Tephritidae).

The main hosts of the melon fly Zeugodacus cucurbitate are cultivated and wild cucurbitaceous plants. In eastern Africa, the melon fly is a major pest of the Solanaceae plant Solanum lycopersicum (tomato). We hypothesized that shared species-specific volatiles may play a role in host attraction.

Management of Cyst and Root Knot Nematodes: A Chemical Ecology Perspective.

Plant parasitic nematode infection of crops can be highly detrimental to agricultural production. Since the discovery that plant roots release chemicals that attract the infective stage of plant parasitic nematodes some 80 years ago, significant progress in identifying the signaling molecules has occurred only relatively recently. Here, we review the literature on chemical ecological studies of two major plant parasitic nematode groups: root knot nematodes in the genus Meloidogyne and cyst nematodes in the genus Globodera because of the negative impact their parasitism has on farming systems in Africa.

Identification of Key Root Volatiles Signaling Preference of Tomato over Spinach by the Root Knot Nematode Meloidogyne incognita.

The root knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, is a serious pest of tomato ( Solanum lycopersicum) and spinach ( Spinacea oleracea) in sub-Saharan Africa. In East Africa these two crops are economically important and are commonly intercropped by smallholder farmers. The role of host plant volatiles in M.

Temperature-dependent models of development and survival of an insect pest of African tropical highlands, the coffee antestia bug Antestiopsis thunbergii (Hemiptera: Pentatomidae).

The antestia bug Antestiopsis thunbergii (Hemiptera: Pentatomidae) is a major pest of Arabica coffee in African tropical highlands. It feeds on coffee plant vegetative parts and berries leading to a direct reduction in coffee yield and quality. This study aimed to determine A.

Parasitic nematode Meloidogyne incognita interactions with different Capsicum annum cultivars reveal the chemical constituents modulating root herbivory.

Plant volatile signatures are often used as cues by herbivores to locate their preferred hosts. Here, we report on the volatile organic compounds used by the subterranean root-knot nematode (RKN) Meloidogyne incognita for host location. We compared responses of infective second stage juveniles (J2s) to root volatiles of three cultivars and one accession of the solanaceous plant, Capsicum annum against moist sand in dual choice assays.

Opposing Roles of Foliar and Glandular Trichome Volatile Components in Cultivated Nightshade Interaction with a Specialist Herbivore.

Plant chemistry is an important contributor to the interaction with herbivores. Here, we report on a previously unknown role for foliar and glandular trichome volatiles in their interaction with the specialist herbivore of solanaceous plants, the tomato red spider mite Tetranychus evansi. We used various bioassays and chemical analyses including coupled gas chromatography-mass spectrometry (GC/MS) and liquid chromatography coupled to quadrupole time of flight mass spectrometry (LC-QToF-MS) to investigate this interaction between cultivated African nightshades and T.

Steroidal glycoalkaloids: chemical defence of edible African nightshades against the tomato red spider mite, Tetranychus evansi (Acari: Tetranychidae).

Background: Tetranychus evansi is an invasive pest of solanaceous crops in Africa, and in the field it differentially attacks edible African nightshades. The chemical basis for the differential attack on these plant species is largely unknown. Using bioassays and chemical analysis, we investigated the differential bioactivity of leaf extracts of three edible African nightshade species, Solanum sarrachoides, S.

Effect of African nightshade species (Solanaceae) on developmental time and life table parameters of Tetranychus evansi (Acari: Tetranychidae).

The effect of five African nightshade (Solanum sp.) species on the biological and demographic parameters of the tomato spider mite, Tetranychus evansi Baker and Pritchard, was examined in the laboratory at 25 +/- 1 degrees C, 70-80% RH and 12L:12D photoperiod. Duration of each development stage, reproduction rate, longevity, intrinsic rate of natural increase (r (m)), and doubling time (DT) of the tomato spider mite on the five nightshade species were calculated.