Bioactivity of oxymatrine and azadirachtin against Tetranychus evansi (Acari: Tetranychidae) and their compatibility with the predator Phytoseiulus longipes (Acari: Phytoseiidae) on tomato

Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae) is one of the main tomato pests in several countries, mainly in Africa, and applications of synthetic acaricides are the main strategy for its control. Efficient biopesticides to suppress pest populations, with low toxicity against natural enemies, is highly desirable for integrated pest management. Here, we evaluated under laboratory conditions the effect of azadirachtin- and oxymatrine-based formulations on each development stage of T. evansi and on the adult stage of the predatory mite Phytoseiulus longipes, the single promising predator of this pest. We also assessed the residual effect of these biopesticides on T. evansi under laboratory conditions on leaflets excised from treated tomato plants maintained in a screen-house 1, 5, and 10 days after application. Azadirachtin-based formulations were effective in controlling T. evansi immature stages. Oxymatrine-based treatments controlled T. evansi immatures and adult females faster than azadirachtin-based treatments. Both biopesticides had no effect on T. evansi eggs, but oxymatrine-based treatments were highly efficient on newly hatched T. evansi larvae. Oxymatrine displayed residual activity that controlled T. evansi up to 10 days after application. Azadirachtin formulations caused lower mortality of P. longipes adults (8–28%) and slightly reduced fecundity (24.8–56.1%). In contrast, oxymatrine treatments caused higher mortality (60–88%) of the predator and reduced substantiality its fecundity (73.1–90.7%). Our findings suggest that Azadirachtin and oxymatrine provide effective control of T. evansi. Azadirachtin may be relatively safer to the predatory mites whereas oxymatrine should be used with caution, to avoid suppression of P. longipes.

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Bed behavioral assessment of tomato varieties in Cote d Ivoire

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v5i1.4513 ◽

2015 ◽

Vol 5 (1) ◽

pp. 513-522

Author(s):

Jean-Claude N'ZI ◽

Lassina FONDIO ◽

Mako Francois De Paul N’GBESSO ◽

Andé Hortense DJIDJI ◽

Christophe KOUAME

Keyword(s):

Behavioral Assessment ◽

Development Stage ◽

Research Centre ◽

Vegetative Development ◽

Potential Yield ◽

Tomato Plants ◽

Bacterial Diseases ◽

Damage Rate ◽

Fruit Damage ◽

Tomato Breeding

Thirty accessions of tomato including twenty eight introduced accessions from The World Vegetable Center-AVRDC and as controls, two commercial varieties Mongal and Calinago, were assessed for agronomic performances at the Experimentation and Production Station of Angud dou of the National Agronomic Research Centre (CNRA) located in the South of Cote d Ivoire. The trial was arranged in a randomized block with three replications. The following parameters were determined at vegetative development stage: plant height at flowering stage, susceptibility of accessions to diseases, day to 50% flowering and day of first harvest, production duration, fruit length, fruit diameter, total number of fruits, number of fruits per plant, potential yield, net yield and fruit damage rate. Results showed that the commercial variety Mongal, with a potential yield of 15.9 and a net yield of 13.1 t ha-1, was the most productive. All the introduced accessions from AVRDC recorded the lowest potential yields from 2.2 to 9.7 t ha-1, and net yields from 1.7 to 8.6 t ha-1. In addition, accessions WVCT8, FMTT847 and WVCT13 were severely infested by bacterial wilt. The reduction of the net yield of tomato accessions resulted in the high fruit damage rates. For the future tomato breeding work, it would be appropriate to introduce into the trials bacterial diseases tolerant varieties. Moreover, some studies could be undertaken to determine the nature of the bacteria involved in the plant wilting and to find out the causal agent of the tomato plants burning at the fructification stage reducing the harvest duration.

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Comparative toxicity of foliar and systemic applications of acetamiprid and imidacloprid against the cotton whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300042176 ◽

1998 ◽

Vol 88 (4) ◽

pp. 437-442 ◽

Cited By ~ 53

Author(s):

A.R. Horowitz ◽

Z. Mendelson ◽

P.G. Weintraub ◽

I. Ishaaya

Keyword(s):

Bemisia Tabaci ◽

Residual Activity ◽

Field Trials ◽

Adult Mortality ◽

Cotton Field ◽

Ovicidal Activity ◽

Laboratory Conditions ◽

Controlled Conditions ◽

Comparative Toxicity ◽

Cotton Whitefly

AbstractComparative bioassays of two chloronicotinyl insecticides, acetamiprid and imidacloprid, against the whitefly Bemisia tabaci (Gennadius), using foliar and systemic applications, were conducted under laboratory conditions and in field trials. Under controlled conditions, the ovicidal activity of foliar applications of acetamiprid on cotton seedlings was much higher than that of imidacloprid. According to LC50 and LC90 values, acetamiprid was 10- and 18-fold more potent than imidacloprid. Both compounds were effective when applied to soil against whitefly adults; however, the potency of imidacloprid was somewhat higher than that of acetamiprid 2, 7 and 14 days after application; resulting (with the concentration of 25 ml a.i./l) in adult mortality of 90, 93, and 96% and 76, 84, and 76% respectively. In an experimental cotton field, the efficacy of foliar applications of 60 g a.i./ha acetamiprid and 210 g a.i./ha imidacloprid was compared. Field residual activity of acetamiprid to whitefly adults lasted for approximately ten days, compared with three days for imidacloprid.

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PERSISTENCE OF IMIDAZOLINONES IN SOILS UNDER A CLEARFIELD SYSTEM OF RICE CULTIVATION

Planta Daninha ◽

10.1590/s0100-83582016340300020 ◽

2016 ◽

Vol 34 (3) ◽

pp. 589-596 ◽

Cited By ~ 7

Author(s):

M.F. SOUZA ◽

M.D. C. NETO ◽

M.I. MARINHO ◽

D.T. SARAIVA ◽

A.T. FARIA ◽

...

Keyword(s):

Dry Matter ◽

Residual Activity ◽

Residual Effect ◽

Dry Matter Accumulation ◽

Red Rice ◽

Indicator Plants ◽

Brazilian State ◽

Commercial Mixture ◽

Randomized Design ◽

Plot Design

ABSTRACT The commercial mixture of imazethapyr and imazapic herbicides has been used for the control of red rice and several other species of weeds found in rice crops; this system called Clearfield. However, its use may limit the succession of non-tolerant crops for long residual activity. The research objective with this work was to determine the persistence of imazethapyr, imazapic and their mixture in three soils in the Brazilian state of Tocantins. Three experiments were conducted in a completely randomized design with four replications, each corresponding to the evaluated soil (Haplic Plinthosol (FX), red-yellow Latosol (LVA) and Haplic Gleysol (GX)). The treatments were arranged in a split plot design, with the allocated plots herbicides (imazethapyr and imazapic alone and commercial mixture) and the plots allocated the 11 evaluation times (1, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150 days after treatment (DAT)), and a control without application. Contacted up long residual effect of imazethapyr and commercial mixture of imazethapyr and imazapic, regardless of assessed soil. After 150 days of applying herbicides or the commercial mixture, their residues in the soil also inhibited approximately 94% of the mass of the dry matter accumulation of the indicator plants. When imazapic was applied alone, there was a higher dry matter accumulation of the indicator plants, indicating less residual effect of this herbicide in the soil and this was attributed to the lower dose of this herbicide applied. The attributes of the soil pH, texture and iron oxides were what most affected the persistence of the herbicides. It can be concluded that the persistence of imazethapyr and imazapic is too long in the Brazilian state of Tocantins soils and the use of these herbicides in the region should be avoided due to the high risk of the occurrence of carryover,or be well planned, as land use in rotation for susceptible crops.

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EVALUATION OF MICROBIAL CONTROL OF THE COTTON LEAFWORM, Spodoptera littoralis (BOISD.) ON TOMATO PLANTS UNDER LABORATORY CONDITIONS

Journal of Plant Protection and Pathology ◽

10.21608/jppp.2012.83722 ◽

2012 ◽

Vol 3 (2) ◽

pp. 91-99

Author(s):

M. Ragab ◽

M- Elnaggar ◽

Marwa Elmesawy

Keyword(s):

Spodoptera Littoralis ◽

Microbial Control ◽

Tomato Plants ◽

Cotton Leafworm ◽

Laboratory Conditions

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RESIDUAL EFFECTS OF PESTICIDES IN PEACH ORCHARDS ON THE MAIZE WEEVIL Sitophilus zeamais (COLEOPTERA: CURCULIONIDAE)

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452016017 ◽

2016 ◽

Vol 38 (3) ◽

Cited By ~ 2

Author(s):

SANDRO DANIEL NÖRNBERG ◽

ANDERSON DIONEI GRÜTZMACHER ◽

DORI EDSON NAVA ◽

RICARDO ALEXANDRE VALGAS ◽

ÂNGELO LUIS OZELAME

Keyword(s):

Residual Effect ◽

Variable Number ◽

Residual Effects ◽

Maize Weevil ◽

Peach Fruit ◽

Laboratory Conditions ◽

Spraying Plants ◽

Peach Trees ◽

And Control ◽

Treatment Application

ABSTRACT The aim of this study was to evaluate the residual effect of pesticides sprayed on peach orchards on S. zeamais. The study consisted of two experiments, according to the method of pesticide application. For Experiment I, pesticides were directly sprayed on peach trees and in Experiment II, the application of pesticides was performed under laboratory conditions. In both Experiments, the effect of pesticides was assessed in laboratory through the release of ten weevils per peach fruit. The effect of treatments was assessed by variable number of surviving insects. The results for pesticides [a.i. (ml or g.100L)] have shown that application of treatments in the field (Experiment I), malathion (200) presented persistence at 1DAT (Days after treatments spraying) and control higher than 80%, and thiametoxan (30) up to 3 DAT , while for phosmet (200) and fenthion (100), the control percentage was over 70% at 1 DAT . Under laboratory conditions, the application of the same insecticides showed control of 100% at 120 HAT (Hours after treatment application). In this context, the use of insecticides by spraying plants must be considered an alternative method for the control of S. zeamais in peach, being necessary to the development and adoption of new control tools for its management.

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API/SC-PCO SOUTHERN CALIFORNIA 1978 OIL SPILL TEST PROGRAM

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1979-1-475 ◽

1979 ◽

Vol 1979 (1) ◽

pp. 475-482

Author(s):

David D. Smith ◽

George H. Holliday

Keyword(s):

Oil Spills ◽

Effective Control ◽

The Public ◽

Operational Testing ◽

Application Techniques ◽

Test Zone ◽

Close Range ◽

Low Toxicity ◽

Test Use ◽

Spilled Oil

ABSTRACT Using Alaskan crude in a special offshore test zone authorized by an EPA Research Ocean Dumping Permit, API/SC-PCO generated a series of small oil slicks for testing dispersant application methods and mechanical cleanup equipment in late September 1978. Seven test slicks ranging in volume from 5 to 20 barrels (bbl) were sprayed with low-toxicity dispersants using a helicopter, a crop-dusting monoplane, and two types of boat-mounted spray systems. A Cyclonet 100 centrifugal skimmer was tested on an eighth slick. In addition, a capsule demonstration in which four one-barrel slicks were generated and dispersed provided agencies, media, and the public the opportunity to witness the use of dispersants at close range. The technical and operational testing was supplemented by detailed chemical and biological monitoring studies and by extensive motion picture and air photographic coverage. Field observations and photographic documentation indicate that: the two dispersants tested dispersed the Alaskan crude; the four dispersant application techniques tested are all viable methods for applying dispersants to oil spills at sea; and, the Cyclonet recovered oil, but the test slick was too small to assess the Cyclonet's probable performance in a major spill situation. This test use of dispersants on oil slicks at sea is a key step toward more effective control and cleanup of spilled oil in the open ocean.

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Control of Red and Green Morphs of Tobacco Aphids (Homoptera: Aphididae) in Flue-Cured Tobacco

Journal of Entomological Science ◽

10.18474/0749-8004-25.4.587 ◽

1990 ◽

Vol 25 (4) ◽

pp. 587-592 ◽

Cited By ~ 3

Author(s):

Robert M. McPherson ◽

Max H. Bass

Keyword(s):

Adverse Effects ◽

High Mortality ◽

Laboratory Tests ◽

Methyl Parathion ◽

Residual Activity ◽

Good Control ◽

Effective Control ◽

Poor Control ◽

Red Color ◽

Myzus Nicotianae

Control of red and green morphs of the tobacco aphid, Myzus nicotianae Blackman, was investigated in field and laboratory tests on flue-cured tobacco in Georgia during 1987–1989. Acephate provided good control of both morphs at 0.75 and 0.5 lbs. AI/acre, and fair to poor control of both morphs at 0.25 and 0.125 lbs. AI/acre. Methomyl, endosulfan, and Endocide Plus (endosulfan plus parathion) also provided effective control of both morphs. Malathion, oxamyl, and tralomethrin provided significantly better control of the green morph than the red morph. Microencapsulated methyl parathion was totally ineffective in controlling either green or red color forms. In laboratory tests, the residual activity of acephate provided high mortality and a reduction in live nymphs produced for up to 14 days after application for both morphs, although these effects were more pronounced with green aphids. The residual activity of methomyl had no adverse effects on either morph 3 days after treatment.

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