Search Results

You are looking at 1 - 10 of 34 items for :

Clear All

The brown marmorated stink bug was first identified in the United States in Allentown, PA, in the mid-1990s ( Hoebeke and Carter, 2003 ). Since then, it has spread to at least 42 states and two Canadian provinces ( Leskey, 2014 ). The brown

Full access

Abstract

A series of outdoor screen-cage tests were carried out over a 4-year period to determine the range of available resistance in cowpea [Vigna unguiculata (L.) Walp.] to the southern green stink bug (SGSB) [Nezara viridula (L.)]. A total of 124 cowpea cultivars, breeding lines, and plant introductions (PI) were evaluated in an unreplicated test in 1981 (Test I); and PI 293476, PI 293557, PI 293570, PI 353074, and PI 354580 were identified as having potentially useful levels of resistance. In a subsequent replicated test in 1982 (Test II), these introductions exhibited less SGSB seed damage and significantly greater seed yield than did the susceptible check Ala 562-3-1-2. PI 293557 and PI 293570 were evaluated further in replicated tests in 1983 (Test III) and 1984 (Test IV) using both infested and uninfested treatments. Both accessions produced appreciable seed yields under conditions that significantly reduced yields in the susceptible checks. Tolerance to SGSB injury appears to be responsible for the resistance exhibited by PI 293557 and PI 293570.

Open Access

Feeding activity by several species of phytophagous stink bugs and coreid bugs (Pentatomidae and Coreidae) on the fruits of pecan [Carya illinoensis (Wangenh.) C. Koch] causes severe economic losses in nut yield and kernel quality. Verification of late-season damage by these insects to pecan nuts has been possible only after examination of the condition of the kernel. Staining nuts with a red fluorescent tracing dye resulted in a differential contrast between the surface of the shell and sites of hemipteran punctures. This technique can be used with the aid of a dissecting microscope to identify hemipteran bug damage by examining the exterior of the shell. Stylet sheaths connecting the packing material on the shell interior to the seedcoat of the kernel have been identified and can be used as confirmatory evidence of hemipteran attack.

Free access
Authors: , , and

Severe economic losses in pecan crop productivity result from phytophagous stink bugs and coreid bugs (Hemiptera) feeding on the kernel. Discriminating hemipteran damage from other late seasonal kernel disorders is often inconclusive. Two additional markers of hermipteran damage have been distinguished and can be used as unequivocal evidence of the feeding activity of these insects regardless of the source of the nuts. Staining pecan nuts with red fluorescent dye differentiates the microscopic hemipteran punctures from the natural markings on the shell. Additional confirmatory evidence can be obtained by recognition of the stylet sheaths connecting the packing material on the shell interior to the seed coat of the kernel. These anatomical evidences of hemipteran feeding should facilitate research studies to evaluate the role of hemipteran attack with late seasonal pecan kernel disorders.

Free access

Company, Minneapolis, MN) were used at labeled rates in rotation once or twice a week for pest management based on field scouting results. Stink bugs have increasingly become a major pest in organic tomato production, as organic insecticides are largely

Open Access

Abstract

In field tests, the most effective film mulch in deterring insects and reducing insect damage to fruits was aluminum. The insects affected were aphids, brown stink bugs, aphid parasites, and Diabrotica spp. Mosaic virus diseases were reduced among aluminum-mulched squash (Cucurbita pepo L.) and cucumber (Cucumis sativus L.) plants. Plant growth, flowering, and fruiting were delayed in tomatoes (Lycopersicon esculentum Mill.) and southernpeas (Vigna unguiculata (L.) Walp.).

Open Access

Eighty-two vegetable growers responded to a survey on pests, beneficial insects, and cover crop use sent in Winter 1993–94 to 314 members of the Virginia Assn. for Biological Farming (VABF) and participants at the 1993 Virginia Sustainable Agriculture Conference. Respondents reported 68 occurrences of insect pests on 99 vegetable crops and herbs. Six insects (flea beetle, squash vine borer, stink bug, cucumber beetles, and Mexican bean beetle) comprised 70% of the occurrences. Squash vine borer and cucumber beetles on cucurbits comprised 24% of all pest occurrences. Insect pests attacked summer squash on 57% and cucumber on 49% of the farms. Average severity of squash vine borer damage was 3.8 (range 0–4, where 0 = no damage and 4 = death or destroyed). Average severity of cucumber beetle damage was 3.0 (severe). Squash vine borer was not observed by farmers on non-cucurbit alternate hosts. Cucumber beetles were observed on horse nettle (10%) and wild nightshades (6%), but on no other plants in most cases (61%) when found on cucurbits. The most frequently observed beneficial insects were lady beetles (64% of the farms), preying mantises (42%), wasps (29%), assassin bugs (18%), and spiders (15%). Only 29% of the farms had purchased beneficial insects, with assassin bugs (10%) and lady beetles (7%) the most common types. Vetches, clovers, rye, and buckwheat comprised 69% of the responses on 23 types of cover crops and mulches used.

Free access

Correlation analysis was used as an aid in developing a scoring system to determine superior lines among 288 entries evaluated for resistance to cowpea curculio, southern green stink bug, and leaffooted bug. The following selection criteria were used (min/max values): days to harvest (58 to 111); sound pods (17% to 100%); curculio larval weight (3.3 to 10.4 mg) and mortality (0% to 80%); larval exit holes per pod (0.0 to 2.2) in a random sample of 25 pods; larval exit holes per pod (0.0 to 8.6) in a 10-pod sample selected for presence of punctures; punctures per pod (one to 15); punctures per exit hole (one to 14); exit holes per puncture (zero to one); curculio damaged seed (0% to 93%); stinkbug damaged seed (0% to 71%); sound seed (0% to 98%); pod length (8 to 25 cm); pod weight (1.3 to 9.2 g); seed per pod (five to 19); and average seed weight (10 to 327 mg). Lines ranking best for pod insect resistance were UCR212 = BAMBEY-5, UCR306 = IT82D-713, UCR194 = BBR-42, PI-218122, UCR90 = T W-3046, UCR200 = 24-lA, PI-115679, PI-145198, AU9lP3 = CCR-20, UCR202 (BROWN SEED), and IT83S-911.

Free access
Author:

Pistachio (Pistacia vera) was successfully introduced into California and initially touted as a tree nut crop with no disease or insect pests. Unfortunately, these expectations were dashed as a number of diseases and pests followed commercial plantings, making plant protection practices integral to production. Verticillium wilt (Verticillium dahliae) devastated early plantings but is now controlled with the use of resistant rootstocks. Botryosphaeria blight (Botryosphaeria dothidea) and alternaria late blight (Alternaria alternata) are recently arrived foliar fungal diseases that blight fruit clusters and defoliate trees, respectively, and multiple fungicide applications are needed for control. The conversion to low volume irrigation systems, specifically to drip or buried drip, has reduced disease. Pruning out botryosphaeria blight infections has reduced overwintering inoculum and disease, while current research aims at accurately predicting infection events to increase fungicide efficacy. A number of hemipteran insect pests have been associated with epicarp lesion: spring treatments have been replaced with dormant carbaryl and oil applications which are less toxic to beneficial insects while controlling phytocoris (Phytocoris californicus and P. relativus) and soft scale pests. Early season insect damage can be tolerated because trees compensate by maturing a higher percentage of remaining fruit kernels. Some mirid (Calocoris spp.) pests can be effectively reduced by eliminating alternate hosts in an effective weed control program. If lygus (Lygus hesperus) populations are present, weeds should not be disturbed from bloom until shell hardening to prevent movement by insects into the trees where feeding can result in epicarp lesion. Stink bugs (Pentatomidae) and leaffooted bugs (Leptoglossus clypealis and L. occidentalis) can penetrate the hardened shell and cause internal nut necrosis along with epicarp lesion. Trap crops are used to monitor pest populations in order to develop treatment thresholds. Degree-day based timing of treatments increase insecticide efficacy for the control of navel orangeworm (Amyelois transitella) and obliquebanded leafroller (Choristonuera rosaceana), but navel orangeworm populations are more effectively managed by destroying unharvested over wintering fruit. Bacillus thuriengiensis sprays, liquid-lime-sulfur, and biological control show promise in controlling obliquebanded leafroller.

Full access

Trials were established in Summer 2002 and 2003 to test the consequences of the application of a kaolin-based particle film (Surround WP, Engelhard Corp.) on gas exchange, nut quality, casebearer density and population of natural predators (insects and arachnids) on pecan (Carya illinoinensis, cv. `Pawnee') trees. Film application started immediately after bud break and was repeated every 7-10 days for seven (2002) or nine (2003) times during the season. On both years, treated trees frequently showed lower leaf temperature (up to 4 °C) than untreated trees. Leaf net assimilation rate, stomatal conductance and stem water potential were not affected by film application. Nut size and quality did not differ between the two treatments. In 2003, shellout (percentage of nut consisting of kernel) was in fact 54.2% and 55.5% for treated and control trees, respectively. Moreover, the two treatments yielded similar percentage of kernel crop grading as fancy, choice, standard and damaged. Similar were also the percentages of kernels that showed damage caused by stink bugs. Only on one date the number of adult yellow pecan aphids (Monelliopsis pecanis) counted on film-treated leaves was lower than in control leaves. In general, the density of common natural predators (lady beetles, green lacewings, spiders) of pecan pests did not differ between the two treatments; however, the number of green lacewing eggs was frequently lower on film-treated leaves. In film-treated trees the number of nutlets damaged by pecan nut casebearer (Acrobasis nuxvorella) was significantly higher than that observed on trees treated with conventional insecticide (24.2% infested nutlets vs. 9.3%, respectively) and did not differ from trees that did not receive either product (29.9%).

Free access