Marcelo Coutinho Picanço

Effect of eggplant transformed with oryzacystatin gene on Myzus persicae and Macrosiphum euphorbiae

Abstract:u2002 The effect of a genetically modified eggplant line expressing oryzacystatin on Myzus persicae (Sulzer) and Macrosiphum euphorbiae (Thomas) was examined. The transgenic eggplant reduced the net reproductive rate (R0), the instantaneous rate of population increase (r), and the finite rate of population increase (λ) of both aphids species compared with a control eggplant line. The mean generation time (T) of the aphids was unaffected by the transgenic plants. Age‐specific mortality rates of M. persicae and M. euphorbiae were higher on transgenic plants. These results indicate that expression of oryzacystatin in eggplant has a negative impact on population growth and mortality rates of M. persicae and M. euphorbiae and could be a source of plant resistance for pest management of these aphids.

Economic injury level for the coffee berry borer (Coleoptera: Curculionidae: Scolytinae) using attractive traps in Brazilian coffee fields.

ABSTRACT n The currently existing sample procedures available for decision-making regarding the control of the coffee berry borer Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) are time-consuming, expensive, and difficult to perform, compromising their adoption. In addition, the damage functions incorporated in such decision levels only consider the quantitative losses, while dismissing the qualitative losses. Traps containing ethanol, methanol, and benzaldehyde may allow cheap and easy decision-making. Our objective was to determine the economic injury level (EIL) for the adults of the coffee berry borer by using attractant-baited traps. We considered both qualitative and quantitative losses caused by the coffee borer in estimating the EILs. These EILs were determined for conventional and organic coffee under high and average plant yield. When the quantitative losses caused by H. hampei were considered alone, the EILs ranged from 7.9 to 23.7% of bored berries for high and average-yield conventional crops, respectively. For high and average-yield organic coffee the EILs varied from 24.4 to 47.6% of bored berries, respectively. When qualitative and quantitative losses caused by the pest were considered together, the EIL was 4.3% of bored berries for both conventional and organic coffee. The EILs for H. hampei associated to the coffee plants in the flowering, pinhead fruit, and ripening fruit stages were 426, 85, and 28 adults per attractive trap, respectively.

Fatores que afetam a germinação do grão de pólen do maracujá: meios de cultura e tipos de agrotóxicos

Temperature, culture medium, incubation period and pH for yellow passion fruit (Passiflora edulis f. flavicarpa) pollen germination, as well the effect of agrotoxics were studied. Temperature of 28 ± 0.5°C, culture medium with 50 g/L of sacarose, 0.2 g/L of boric acid and 1.0 g/L of calcium nitrate showed better germination of P. edulis f. flavicarpa pollen. No effect of the incubation period (17 and 48 hours) was registered for pollen germination of this plant. Percentage of pollen germination of P. edulis f. flavicarpa was not affected by the acaricid Dicofol + Tetradifon and by the insecticides Cartap, Fenpropathrin, and Abamectin. There was a small reduction in pollen germination in the presence of insecticides Malathion, Fenthion, Thrichorfon, Vamidothion, Deltamethrin, Methyl Parathion and the spreader-sticker N-dodecil benzen sodium sulphate. Ethion and Lambdacyhalothrin had severe effect on pollen germination of this plant.

Influência de Trigona spinipes Fabr. (Hymenoptera: Apidae) na polinização do maracujazeiro amarelo

O estudo teve como objetivo a avaliacao da interferencia de Trigona spinipes Fabr. (Hymenoptera: Apidae) na polinizacao e frutificacao do maracujazeiro amarelo (Passiflora edulis f. flavicarpa). Foram realizadas polinizacoes natural e artificial, em flores com ou sem injurias de T. spinipes. Foram avaliadas a percentagem de vingamento das flores, teor de solidos soluveis da polpa e peso dos frutos. As flores com injurias de T. spinipes apresentaram maior vingamento (64%) que aquelas sem tais injurias (32%), quando polinizadas naturalmente. Flores que receberam visitas de T. spinipes apos a antese (polinizacao natural e artificial sem cobertura), originaram frutos com menor percentagem de peso de polpa mais sementes (43 e 42%, respectivamente), em relacao aqueles provenientes de flores polinizadas artificialmente com cobertura (51%).

Identificação e quantificação dos componentes de perdas de produção do tomateiro em ambiente protegido

ABSTRACT Identification and quantification of tomato yield losscomponents in unheated greenhouse The tomato production components of loss were identified andquantified in unheated greenhouse, in the summer-autumn period,evidencing the tomato critical production component and the losskey-factor, using the methodology of the crop life table. Theexperiment was conducted at the Universidade Federal de Vicosa,Minas Gerais State, Brazil, from January to June 2001 and consistedof two treatments (cultivar Santa Clara I 5300 and hybrid DeboraPlus) in a randomized complete block design with 5 replications.During the tomato cycle, the number of dead plants, its causes andthe number of flowers and fruits/plant were evaluated. At harvest,the healthy fruits were counted, weighted and classified; the causesof fruit damage were identified and the loss quantified. There wasno significant difference between commercial yield of ‘Sta. Clara’(40.18 t/ha) and ‘Debora Plus’ (54.98 t/ha). The classified yieldsbetween ‘graudos A’ fruits (‘Sta. Clara’: 24.39 t/ha; ‘Debora Plus’:32.32 t/ha) were not different either. The yield of ‘medio extra’ fruits(‘Sta. Clara’: 7.60 t/ha; ‘Debora Plus’: 10.77 t/ha) and the sum of‘medio especial’ with ‘pequenos’ fruits (‘Sta. Clara’: 8.19 t/ha;‘Debora Plus’: 11.90 t/ha) were low. Total losses were moreinfluenced by fruits (r = 0.89) (

Qualidade da semente e senescencia de genotipos de soja sob dois niveis de infestacao de percevejos (Pentatomidae).

The objective of this research was to evaluate the genotypes CR-1 and CR-3, from the genetic improvement program of soybean flavor of the Federal University of Vicosa, in Vicosa, MG, Brazil, under two levels of Heteroptera infestation. The genotypes tested were CR-1, CR-3, Cristalina, Davis (susceptible genotype) and IAC-100 (resistant genotype). The genotypes CR-1, CR-3, Davis and Cristalina under low level of infestation (2.8 Heteroptera/beating) produced similar percentage of normal seeds (57%) but inferior to the genotype IAC-100 (77%). Under high level of infestation (6.42 Heteroptera/beating), the genotypes CR-1, CR-3 and Cristalina produced similar percentage of normal seeds but inferior to the genotypes Davis (43%) and IAC-100 (59%). All genotypes showed low level of leaves retention (less than 6%) when cultivated under low level of infestation by Heteroptera but under high level of infestation of these bugs, the genotypes CR-1 and IAC-100 showed smallest level of leaf retention (less than 5%) followed by Davis and CR-3 (6-20%) and Cristalina (21-40%). The genotypes CR-1, IAC-100 and Davis showed no green stem under low infestation, contrary to what was registered for CR-3 (3.6% green stem) and Cristalina (11% green stem). IAC-100, CR-1, and Davis showed the smallest percentages of plants with green stem (6.4, 10.3 and 18.3%, respectively) compared to CR-3 (64.8%) and Cristalina (77.3%).

Tomato plant inheritance of antixenotic resistance to tomato leafminer

The objective of this work was to determine the inheritance of resistance by antixenosis in tomato plants (Lycopersicon esculentum) to tomato leafminer (Tuta absoluta (Lepidoptera: Gelechiidae)). Evaluations were performed for tomato plants of the generations P1, P2, F1, F2, RC1 and RC2. The measured characteristic in the parents, BGH-1497 (P2 male) and Santa Clara (P1 female), and in the F1, F2, RC1 and RC2 generations was the number of eggs per plant. This number was converted to the oviposition nonpreference index. The inheritance of antixenosis resistance of genotype BGH-1497 is ruled by a gene of greater effect and polygenes in epistatic interactions, with a phenotypic proportion of 13:3 between susceptible and resistant genotypes, respectively.