Females of Ceratitis capitata are facultative polyandrous, with remating more common in laboratory strains rather than wild ones. In the application of the Sterile Insect Technique (SIT) against this pest, large overflooding ratios of sterile : wild males can increase the remating frequency. Females that mate for the first time with a sterile male tend to remate more frequently. The exposure of sterile males to ginger root oil (GRO) is used in C. capitata SIT programmes to increase the sterile male mating success. Exposing males to an ‘aromatherapy’ with GRO may also increase the remating frequency among wild females. The frequency of wild females remating, number of matings per female, the refractory period between the first and second mating, and the duration of the first and second matings of wild females were determined under laboratory conditions for three mating scenarios that included wild males only or wild males competing with sterile males (either GRO‐treated or non‐treated). Wild females first mated with sterile males exposed to GRO had their remating rate over the following 6 days and the mean number of matings per female reduced in comparison to those first mated with non‐exposed sterile males, from 62.5% to 32.2% and from 3.1 to 1.6 respectively. The remating parameters of females mated with sterile GRO‐exposed males resembled those of females mated with wild males.

En el control de plagas agrícolas, los insecticidas representan la principal alternativa disponible. Para analizar la magnitud de su uso, se realizaron 539 entrevistas a agricultotes en los siguientes cultivos: Cucurbitaceae: melón, Cucumis melo L. y sandía, Citrullus lanatus (Thunb.), Fabaceae: frijol, Phaseolus vulgaris L., Solanaceae: papa, Solanum tuberosum L., pimiento, Capsicum annuum L. y tomate, Solanum lycopersicum L., ubicados en las provincias: Chimborazo, El Oro, Guayas, Loja y Santa Elena. Se recabó información sobre plagas importantes, tipo de manejo y si resultaba plaguicida químico, se consignaba: nombre genérico, ingrediente activo, toxicidad aguda, dosificación aplicada, frecuencia de aspersiones, períodos de carencia y mezclas de productos. El total de los entrevistados manifestó utilizar mezclas de insecticidas, generalmente elevando las dosificaciones recomendadas sin tomar en cuenta los periodos de carencia. Además, señalaron realizar 2,6; 1,1; 0,5; 2,0 y 2,8 aspersiones semanales promedios para cucurbitáceas (melón y sandía), frijol, papa, pimiento y tomate, respectivamente. Las plagas principales mencionadas fueron: áfidos (Hemiptera: Aphididae) en cucurbitáceas y pimiento, Liriomyza spp. en frijol (Diptera: Agromyzidae), Premnotrypes vorax (Hustache) (Coleoptera: Curculionidae) en papa y Prodiplosis longifila Gagné (Diptera: Cecidomyiidae) en tomate. Aproximadamente el 80% de los insecticidas utilizados pertenecen a las Clase I y II. Los resultados indicaron altas frecuencias de aspersiones, dosificaciones elevadas y alta toxicidad para vertebrados en los insecticidas usados. Dado el impacto de los insecticidas, es necesario estudiar los desequilibrios en los agroecosistemas, efectos en salud y ambiente, así como validar alternativas ecológicas y socioeconómicamente más racionales.

The Ethiopian fruit fly, Dacus ciliatus (Loew) (Diptera: Tephritidae), is a significant pest of cucurbit crops in Asia and Africa and is currently controlled with insecticides. The sterilizing effect of gamma radiation on D. ciliatus adults was investigated to assess the suitability of sterile insect technique (SIT) for use as an alternative, non‐chemical strategy for the control of this pest. Late pupae (48 h before emergence) were irradiated with 60, 80, 100, 120, and 140 Gy of gamma rays emitted by a 60Co source. Following emergence, the biological characteristics of the experimental cohorts (including all possible male‐female combinations of irradiated and untreated flies) were recorded. No significant negative effects of irradiation on pupal eclosion or the ability of newly emerged flies to fly were observed. Samples of eggs at reproductive fly‐ages (12‐, 15‐, and 17‐day‐old pairs) were collected and their hatch rates were assessed. At 60 Gy, females were completely sterilized, whereas complete sterilization of the males was observed only at 140 Gy (a small amount of fertility persisted even at 120 Gy). In addition to the above experiments, three fruit infestation trials were conducted with zucchini [Cucurbita pepo L. (Cucurbitaceae)] as the plant host and the pupae produced in those trials were collected and recorded. We observed significant (ca. 10%) infestation following treatment with up to 120 Gy and zero progeny only at 140 Gy, mirroring the egg‐hatch results. Our findings support the feasibility of SIT for the control of D. ciliatus.

The sterile insect technique (SIT) is widely used as part of an integrated approach to reduce field populations of the Mediterranean fruit fly (Ceratitis capitata, Diptera: Tephritidae). Aromatherapy based on exposure to ginger root oil (GRO) volatiles is known as a method to significantly improve the sexual performance of sterile medfly males, and is being used in many mass‐rearing facilities around the world. However, the optimum dose of GRO is not well defined. This work evaluated in laboratory cages four different doses of GRO and a control (0, 0.1, 0.25, 0.5 and 0.75 ml/m3), and two different methods to hold flies prior to release (paper bags and plastic cages). The objective was to find the lowest dose that provides optimal improvement in mating performance of sterile males when competing with wild males for wild females and optimal reduction in fertility of wild females. Egg hatch, copula duration, the Relative Sterility Index (RSI), and a Competitiveness (C) value (based on RSI) were calculated for each treatment to assess male sexual performance and induction of sterility. The method used to hold flies did not influence the aromatherapy effect. The mean time spent by wild females in copula with wild males was significantly longer than with sterile males for all treatments, except when sterile males were treated with 0.1 ml of GRO/m3. Amongst all doses studied, it is recommended to apply the lowest dose, 0.1 ml of GRO/m3, since at this dose both the RSI and induced sterility reached the highest levels, and were not statistically different from the 0.25 and 0.5 GRO/m3 doses. Indeed, this dose showed a very significant improvement in the mating competitiveness of sterile males aromatically treated with GRO.

No abstract

página do horticultorO morangueiro ( Fragaria x ananassa Duch.) é plantado em todos os continentes (Branzanti, 1989;Roudeillac, 1999) e seu cultivo é bastante desenvolvido em países como Estados Unidos, Espanha, Japão, Itália, Coréia do Sul e Polônia (Resende et al., 1999). A grande popularidade se deve aos esforços dos melhoristas que, desde o século passado, têm desenvolvido cultivares adaptadas às mais diversas condições ambientais (Hancock et al., 1996).No Brasil, a produção de morangos se expande a cada ano, predominando o cultivo em pequenas propriedades rurais, com m ão-de-obra familiar (Resende et al., 1999). Os estados de São Paulo, Minas Gerais e Rio Grande do Sul são os maiores produtores, onde destaca-se o cultivo das cultivares Campinas, Dover e Princesa Isabel (Botelho, 1999;Cruz, 1999;Santos, 1999b). A cultivar Campinas, desenvolvida no IAC na década de sessenta, a partir do cruzamento entre as cultivares norteamericanas Donner e Tahoe, causou um salto na produtividade e qualidade dos morangos produzidos no país. Após trinta anos do lançamento, 'Campinas' ainda era a cultivar mais plantada nos principais estados produtores (Camargo & Passos, 1993) e continua tendo expressiva importância (Botelho, 1999;Cruz, 1999). 'Princesa Isabel' também foi desenvolvida no IAC, na década de oitenta, e resultou do cruzamento entre as cultivares Alemanha e Jundiaí e seus principais atributos referem-se à boa produtividade, precocidade, tamanho e textura dos morangos e facilidade de colheita (Campinas, 1989). A cultivar norte-americana Dover foi introduzida no Brasil visando amenizar os danos da flor-preta, atualmente, a principal moléstia da cultura, e seu cultivo vem se expandindo (Passos, 1999).Devido à suscetibilidade das principais cultivares plantadas a diversas doenças e pragas (Paulus, 1990;Dias, 1999;Fadini & Alvarenga, 1999) RESUMOAvaliou-se a produtividade de morangueiro (Fragaria x ananassa Duch.), cultivares Campinas, Dover e Princesa Isabel em sistema de cultivo orgânico sem e com adubação de cobertura, na perspectiva de utilizá-los em programas de melhoramento. O experimento, realizado na UFV, consistiu do fatorial 3 x 3 em blocos casualizados (DBC) com cinco repetições. Os fatores estudados foram cultivares (Campinas, Dover e Princesa Isabel) e adubação de cobertura (sem adubação, com adubação sólida e com adubação líquida). O plantio foi feito em 16/05/00, em canteiros com 0,8 m de largura e espaçamento entre plantas de 0,4 x 0,4 m. Cada parcela compreendeu a área de 0,8 m x 1,6 m, contendo 4 plantas úteis e 8 plantas no total. O desempenho das cultivares foi avaliado entre 18/07 e 03/11/ 00. A adubação de cobertura não influenciou a produtividade das cultivares, provavelmente devido à fertilidade já disponível no solo em decorrência da adubação de plantio (40 t.ha -1 de composto orgâ-nico). A cultivar Dover foi a que apresentou maior número de frutos comerciáveis (média de 54,9 morangos.planta -1 ), enquanto o peso total de morangos comerciáveis produzidos por 'Dover' (423,1 g.planta -1 ) e 'C...

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Brazil is one of the largest importers of this cereal, and wheat breeding programs are attempting to increase productivity and reduce external dependence. The objectives of this study were to quantify the spring wheat genetic gain in Brazil between 1984 and 2014 using data from multienvironment trials, and to verify if the genetic gain stagnated after the 2000s. This study used a highly unbalanced dataset containing grain yield (GY) data from 187 spring wheat trials that were performed at 25 locations between 2002 and 2015. In total, 126 cultivars, released between 1985 and 2014, were evaluated over 14 crop seasons. The cultivar evaluation indicated that there was a genetic gain in GY of 33.9 kg ha−1 yr−1 (r2 = 0.53, P < 0.01), which represents an increase of 1.28% yr−1. The dataset showed a linear regression for the genetic gain and indicates that wheat genetic gain has not stagnated in Brazil after the 2000s.

-In forty years of genetic breeding of wheat, Embrapa (Brazilian Agricultural Research Corporation)