Non-preference Test Research Articles

Resistance in lima bean to Aphis craccivora (Hemiptera: Aphididae)

The cowpea aphid (Aphis craccivora) can be an important pest on lima bean (Phaseolus lunatus L.). The objective of this work was to evaluate the effect of different genotypes of lima bean on the biology of A. craccivora and to identify possible sources of resistance to aphids under laboratory conditions. Two trials were set up, an antibiosis and a free-choice antixenosis test. Furthermore, the density of the trichomes on the leaf surface was determined for each genotype. Aphid life table parameters were similar in the antibiosis experiments for all of the genotypes tested. The calculated life table for the lima bean genotype used several parameters, namely Net Reproduction Rate (Ro) = 49.23; Time interval between each generation (T) = 10.24, Intrinsic rate of natural increase (rm) = 0.38; Finite rate of population increase (λ) = 1.46 and Time for population to duplicate (TD) = 1.82. The results of non-preference tests showed that genotype UFPI-887 exhibited antixenosis resistance when compared to genotypes UFPI-882 and UFPI-881. The trichome density average varied from 126.29 trichomes/mm2 in genotype UFPI-882 to 42.20 trichomes/mm2 in genotype UFPI-883. There was no correlation between trichome density in the leaves and no preference of A. craccivora for leaves of P. lunatus.

Simple genetic inheritance conditions resistance to Liriomyza sativae in melon

The leafminer Liriomyza sativae (Diptera: Agromyzidae) stands out as the main plant health problem in melon in the Northeast region of Brazil, which is the main region for production and export of the fruit. Genetic resistance of plants is an important strategy in management of this pest. The plant BAGMEL 56-R was selected as a new source of resistance to L. sativae through antibiosis; this resistance is characterized by the death of larvae soon after they begin feeding on the leaf mesophyll; the result is leaf mines that are small and insignificant in terms of yield reduction. Lines with contrasting levels of resistance were obtained from the progenies of this source of resistance through successive self-pollinations, conducted by the pedigree breeding method. Through the segregation pattern of the progenies and the test cross, the genetic nature of resistance was determined; one gene with complete dominance conditions resistance. The name Liriomyza sativae resistance and the symbol Ls are suggested to represent this new gene. In addition, through a non-preference test with lines in contrast for antibiosis and the susceptible hybrid ‘Goldex’, the presence of antixenosis was observed in this source of resistance. Probably, these different types of resistance in the source BAGMEL 56-R are associated with distinct defense mechanisms. Therefore, with this new source, introgression of resistance to L. sativae in elite lines or commercial hybrids of melon is possible.

DEVELOPMENT OF Tetranychus urticae KOCH (ACARI: TETRANYCHIDAE) IN DIFFERENT STRAWBERRY CULTIVARS

ABSTRACT Two-spotted spider mite, Tetranychus urticae Koch, is considered the main pest in strawberry crop. The control of this species is hampered by the low efficiency of products currently used, occurrence of populations resistant to acaricides and high reproductive potential of this pest. This leads to the use of pesticides and increased agrochemical residues in fruits. The use of resistant cultivars is considered the ideal control method because they maintain mite populations below levels of economic damage, minimize the environmental impact of pesticides at no extra cost to the farmer, and serve as an auxiliary tool in integrated pest management. In this sense, this study evaluated the resistance of strawberry cultivars to T. urticae by studying the development of its biological aspects. Comparative biology experiments and non-preference tests for feeding and oviposition for spider mite were carried out in 16 strawberry cultivars under laboratory conditions. Based on results, it was found that Camarosa, Florida Festival, IAC Campinas and Sabrosa strawberry cultivars indicated the possibility of antibiosis type resistance to spider mite, influencing the preference to food, development and oviposition, indicating the existence of differentiated reaction in population development among cultivars.

Resistance in cowpea cultivars to Bruchidius atrolineatus (PIC) (Coleoptera: Chrysomelidae: Bruchinae)

ABSTRACT: This study aimed to assess the resistance in cowpea cultivars to Bruchidius atrolineatus (Pic) attack. The experiment was conducted at the Faculdade de Ciências Agrárias e Veterinárias of Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Jaboticabal (SP). The following cultivars were used: BR17 Gurgueia, BR3 Tracuateua, BRS Novaera, Sempre Verde, BRS Milênio, and BRS Urubuquara. The non-preference test without choice evaluated the number of viable eggs, unviable and total posed by insects in grains, after 25 days of confinement. In addition, it was observed, in a daily basis, the total dry matter consumed and dry matter consumed per insect; male and female mass; male, female and total egg-adult cycle length; male and female longevity; sex ratio; number of emerged insects and percentage of emerged insects. The non-preference test with free choice evaluated the number of viable, unviable and total eggs and adult attractiveness after 24 hours and seven days of release. Sempre Verde cultivar was the least preferred for oviposition in the test without choice and showed lower number and percentage of emerged insects. BRS Milênio had the lowest total dry mass consumed and dry mass consumed per insect.

Incorporation of Biorational Insecticides with Neonicotinoids to Combat Resurgence ofTetranychus urticae(Prostigmata: Tetranychidae) on Rose

Rose plants were treated with 2 neonicotinoids (imidacloprid and acetamiprid), 3 biorationals (spinosad, emamectin benzoate, and Beauveria bassiana [Bals.-Criv.] Vuill. [Hypocreales: Cordycipitaceae]), and combinations of neonicotinoids and biorationals to control two-spotted spider mites (Tetranychus urticae Koch; Prostigmata: Tetranychidae) on rose. Toxicity bioassays revealed that imidacloprid drench, imidacloprid foliar applications, and acetamiprid treatments significantly increased spider mite numbers, whereas treatments with spinosad or with emamectin either alone or in combinations with imidacloprid and acetamiprid resulted in significantly fewer spider mites compared with the untreated control. Beauveria bassiana was least effective in controlling the spider mite population. The fecundity experiment indicated that the imidacloprid drench and foliar treatments significantly increased the number of mite eggs produced during observation days up to 9 d after treatment (DAT) for the drench treatment and up to 7 DAT for the foliar treatments. Acetamiprid did not induce any significant changes in spider mite egg production. Spinosad, emamectin, and B. bassiana alone or in combinations induced significant reductions in egg numbers compared with the control at almost all observation days. Both preference and non-preference tests indicated that the drench and the foliar applications with imidacloprid resulted in significantly more spider mites on treated leaf discs at 5 and 7 DAT than on untreated leaves. In conclusion, spinosad and emamectin in combinations with the neonicotinoids can be incorporated into the integrated pest management of the two-spotted spider mite on roses.

Determinação dos tipos de resistência a Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) em genótipos de soja

The aim of this work was to evaluate the resistance types in soybean genotypes to Spodoptera cosmioides (Walker) in laboratory. Soybean genotypes assessed were as follows: ‘IAC 100’ (resistance standard), ‘BR16’ (susceptible standard), ‘Dowling’, PI 227687, PI 274454, ‘IGRA RA 626 RR’, PI 227682, ‘BRSGO 8360’, ‘IGRA RA 516 RR’ and ‘P 98Y11 RR’. Free-choice and no-choice feeding non-preference tests were done using two newly-hatched larvae per genotype or one third-instar larva per genotype in both tests. Larvae attractiveness was evaluated in different times, and at the end of the experiments the leaf area consumed was quantified. In the antibiosis test, newly-hatched larvae were individualized into Petri dishes, where leaflets of the genotypes were offered over the larval stage, and the following biological parameters were assessed: period and viability of larvae, pupae and overall (larvae + pupae), weight of larvae and pupae, sex ratio and adults longevity. Overall, in the feeding preference tests, significant differences were not found in leaf consumption among the genotypes. In the antibiosis assay, genotypes PI 227687, PI 227682 and ‘IAC 100’ caused 100% larval mortality and the lowest weight of larvae, ranging between 37.65 and 85.56 mg. All soybean genotypes evaluated do not exhibit feeding non-preference type resistance to S. cosmioides, and PI 227687, PI 227682 and ‘IAC 100’ highlighted for possessing antibiosis.

Feeding non-preference by Spodoptera frugiperda and Spodoptera eridania on tomato genotypes

Larvae of the genus Spodoptera spp. are highly polyphagous and can cause economical losses in several agricultural crops. Given their growing importance in the tomato crop, especially for industry, this work aimed to evaluate the feeding non-preference by larvae of Spodoptera frugiperda (J. E. Smith, 1797) and Spodoptera eridania (Cramer, 1782) on tomato genotypes and classify them by the levels of resistance. The commercial cultivar Santa Clara was set as the susceptible standard and line PI 134417 as the resistant standard to evaluate the lines PI 134418, PI 126931, LA 462 and LA 716. Feeding non-preference tests were performed under non-choice and free-choice conditions to evaluate the genotype attractiveness to larvae at predetermined times after their release, as well as the leaf area consumed. Overall, the genotypes LA 716 and PI 126931 were the least attractive to S. frugiperda, whereas Santa Clara was the most attractive and consumed. For S. eridania, the genotypes PI 126931, LA 462, LA 716 and PI 134418 were the least preferred for feeding, and Santa Clara and PI 134417 were the most attractive and consumed. The genotypes LA 716 and PI 126931 are moderately resistant to S. frugiperda and S. eridania; PI 134418 and LA 462 are moderately resistant to S. eridania; PI 134417 is susceptible to S. frugiperda and S. eridania; and Santa Clara is highly susceptible to both S. frugiperda and S. eridania.

Endophyte Isolate and Host Grass Effects on Chaetocnema pulicaria (Coleoptera: Chrysomelidae) Feeding

Endophytic fungi belonging to the genus Neotyphodium, confer resistance to infected host grasses against insect pests. The effect of host species, and endophtye species and strain, on feeding and survival of the corn flea beetle, Chaetocnema pulicaria Melsheimer (Coleoptera: Chrysomelidae) was investigated. The grass-endophyte associations included natural and artificially derived associations producing varying arrays of common endophyte-related alkaloids or alkaloid groups, peramine, lolitrem B, ergovaline, and the lolines. Preference and nonpreference tests showed that C. pulicaria feeding and survival were reduced by infection of tall fescue with the wild-type strain of N. coenophialum, the likely mechanism being antixenosis rather than antibiosis. In the preference tests, endophyte and host species effects were observed. Of the 10 different Neotyphodium strains tested in artificially derived tall fescue associations, eight strongly deterred feeding by C. pulicaria, whereas the remaining two strains had little or no effect on feeding. Infection of tall fescue with another fungal symbiont, p-endophyte, had no effect. Perennial ryegrass, Lolium perenne L., infected with six strains of endophyte, was moderately resistant to C. pulicaria compared with endophyte-free grass, but four additional strains were relatively inactive. Six Neotyphodium-meadow fescue, Festuca pratensis Huds., associations, including the wild-type N. uncinatum-meadow fescue combination, were resistant, whereas three associations were not effective. Loline alkaloids seemed to play a role in antixenosis to C. pulicaria. Effects not attributable to the lolines or any other of the alkaloids examined also were observed. This phenomenon also has been reported in tests with other insects, and indicates the presence of additional insect-active factors.

Resistência de genótipos de soja à mosca branca Bemisia tabaci (Genn.) biótipo B (Hemiptera: Aleyrodidae)

Este trabalho foi realizado com o objetivo de avaliar em sete genótipos de soja, os tipos de resistência à mosca-branca Bemisia tabaci Genn. biótipo B, bem como a correlação entre a densidade dos tricomas presentes nos folíolos dos genótipos estudados e a preferência de oviposição da espécie. Os ensaios foram conduzidos na área experimental e no Laboratório de Resistência de Plantas a Insetos do Departamento de Fitossanidade, da Faculdade de Ciências Agrárias e Veterinárias - Campus de Jaboticabal - UNESP, Jaboticabal, SP, entre outubro de 2000 e janeiro de 2001. Dentre os genótipos testados, BR-82 12547 e PI 229358 apresentaram resistência do tipo nãopreferência para oviposição à mosca branca; a oviposição foi correlacionada positivamente com a densidade total de tricomas. Assim, PI 227687, com a maior quantidade de tricomas, foi o genótipo mais ovipositado, enquanto que BR-82 12547 e PI 229358, com as menores quantidades de tricomas, foram os menos ovipositados. O ensaio de antibiose foi realizado utilizando-se cinco genótipos: BR-82 12547, IAC 100, IAC 78-2318, PI 229358 e PI 227687, selecionados do ensaio de não-preferência para oviposição. IAC 100 destacou-se por afetar negativamente B. tabaci biótipo B, prolongando o período ninfal (12,8 dias) e reduzindo a emergência de adultos (80,0%).

Extratos aquosos de Trichilia pallida e a traça-do-tomateiro

Avaliou-se o efeito de extratos aquosos de folhas e de ramos da planta inseticida Trichilia pallida sobre o desenvolvimento e oviposição da traça-do-tomateiro, Tuta absoluta. Acompanhou-se o desenvolvimento do inseto em folhas de tomateiro (Lycopersicon esculentum, cv. Santa Clara) previamente submersas nos extratos nas concentrações de 0,1; 1,0 e 5,0%. Também foi avaliado o efeito dos extratos de folhas a 1,0 e 5,0%, pulverizados sobre ovos do inseto, e a não-preferência para oviposição, com chance de escolha, em folhas de tomateiro com e sem esse extrato a 5%. Verificou-se que os extratos de folhas e de ramos prejudicam o desenvolvimento do inseto afetando principalmente a fase larval, aumentando a duração e reduzindo a viabilidade deste período. O extrato de folhas apresenta maior atividade que o de ramos, reduzindo a viabilidade larval a valores próximos a 20%, já na concentração de 1%. O extrato de folhas a 5% não apresenta efeito ovicida mas, o substrato tratado pode tornar-se menos preferido para oviposição.

INFLUENCE OF SNAP BEAN PHENOLOGY ON HELIOTHIS ZEA (BODDIE) (LEPIDOPTERA: NOCTUIDAE) OVIPOSITION

In greenhouse preference tests Heliothis zea (Boddie) moths oviposited significantly more eggs on blooming snap bean, Phaseolus vulgaris L., than on pre-blooming plants. When moths were held in cages containing only 1 plant stage (non-preference tests) significantly more eggs were laid on blooming snap beans than on either pre- or post-bloom plants. Furthermore, this ovipositional response to blooming plants was much more striking after moths were caged for 3 nights. During nights 4–6, oviposition continued at a similar rate on blooming plants, while pre- and post-bloom plants received very few eggs. Regardless of plant stage, most eggs were laid on the top and bottom of large snap bean leaves.

Intercorrelations Among Musical Aptitude Profile and Seashore Measures of Musical Talents Subtests

IN 1919 THE FIRST standardized group aptitude test, the Seashore Measures of Musical Talent} was published. This battery, in its latest revised form (Seashore, 1960), is comprised of six subtests which measure basic auditory sensory discrimination. According to the test author (Seashore, 1938), everything that is rendered as music or heard as music may be expressed in terms of the concepts of the sound Pitch, Loudness, Rhythm, Time, Timbre} and Tonal Memory are tested by requiring subjects to compare a pair or short series of tones which are produced on a beat-frequency oscillator (except on the Tonal Memory subtest). Because these subtests are supposedly void of the interaction of melody, rhythm, and expression, music psychologists (Mursell, 1937) have described and condemned the battery as being atomistic and unmusically-oriented. Specifically, the omnibus group, antagonists of the Seashore approach, believe that musicality consists of more than just the ability to discriminate audio-acoustical differences in the sound wave. Further, these music psychologists, many of whom are European (Lowery, 1940; and Mainwaring, 1947), argue that aptitude is not compnsed of separate abilities, but rather, that it is one general ability. They contend that a instrument should be used as the medium for stating music test items and that the content of each item should, in and of itself, have musical meaning. The comparatively new Musical Aptitude Profile (Gordon, 1965) has been described as an eclectic test because both preference and nonpreference subtests constitute the test battery and also because, while the content of the test items is and is performed by professional musicians, the battery does, nevertheless, provide for the evaluation of seven postulated dimensions of aptitude. The dimensions measured by this standardized group test are classiSed into three main divisions: Tonal Imagery, Rhythm Imagery, and Musical Sensitivity. Two separate subtests are provided for each of the nonpreference tests: Melody and Harmony for Tonal Imagery, and Tempo and Meter for