Molecular mapping of two loci that confer resistance to Asian rust in soybean

Asian soybean rust (ASR) is caused by the fungal pathogen Phakopsora pachyrhizi Sydow & Sydow. It was first identified in Brazil in 2001 and quickly infected soybean areas in several countries in South America. Primary efforts to combat this disease must involve the development of resistant cultivars. Four distinct genes that confer resistance against ASR have been reported: Rpp1, Rpp2, Rpp3, and Rpp4. However, no cultivar carrying any of those resistance loci has been released. The main objective of this study was to genetically map Rpp2 and Rpp4 resistance genes. Two F(2:3) populations, derived from the crosses between the resistant lines PI 230970 (Rpp2), PI 459025 (Rpp4) and the susceptible cultivar BRS 184, were used in this study. The mapping populations and parental lines were inoculated with a field isolate of P. pachyrhizi and evaluated for lesion type as resistant (RB lesions) or susceptible (TAN lesions). The mapping populations were screened with SSR markers, using the bulk segregant analysis (BSA) to expedite the identification of linked markers. Both resistance genes showed an expected segregation ratio for a dominant trait. This study allowed mapping Rpp2 and Rpp4 loci on the linkage groups J and G, respectively. The associated markers will be of great value on marker assisted selection for this trait.

Analysis of the workers head transcriptome of the Asian subterranean termite, Coptotermes gestroi

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Taenia solium and Taenia saginata: Identification of sequence characterized amplified region (SCAR) markers

Cysticercosis is one of the most important zoonosis, not only because of the effects on animal health and its economic consequences, but also due to the serious danger it poses to humans. The two main parasites involved in the taeniasis-cysticercosis complex in Brazil are Taenia saginata and Taenia solium. Differentiating between these two parasites is important both for disease control and for epidemiological studies. The purpose of this work was to identify genetic markers that could be used to differentiate these parasites. Out of 120 oligonucleotide decamers tested in random amplified polymorphic DNA (RAPD) assays, 107 were shown to discriminate between the two species of Taenia. Twenty-one DNA fragments that were specific for each species of Taenia were chosen for DNA cloning and sequencing. Seven RAPD markers were converted into sequence characterized amplified region (SCAR) markers with two specific for T. saginata and five specific for T. solium as shown by agarose gel electrophoresis. These markers were developed as potential tools to differentiate T. solium from T. saginata in epidemiological studies. © 2007 Elsevier Inc. All rights reserved.

Ratings since the Asian crisis

Includes bibliography

How optimal are the extremes?: Latin American exchange rate policies during the Asian crisis

Includes bibliography

An Asian perspective on the desirable international financial architecture

Includes bibliography

The changing nature of Asian-Latin American economic relations

Includes bibliography

Effect of nozzle angle and air-jet parameters in air-assisted sprayer on biological effect of soybean asian rust chemical protection

Aiming at improving the efficiency control of Phakopsora pachyrhizi, this research evaluated different application techniques, using spray deposits and yield parameters of soybean crop. Two experiments were carried out in the experimental area of FCA/UNESP - Botucatu, SP, Brazil, in the soybean crop, Conquista variety, in the 2006/2007 season. The first experiment was arranged in random blocks with eight treatments and four replications. The treatments were conducted in factorial arrangement 4×2 (four air levels 0, 9, 11 and 29 km/h combined at two nozzle angles 0 and 30°) using AXI 110015 nozzles. Ten plants on each plot were selected for sampling spray deposits. Artificial targets were fixed on plants, two in the top and another two in the bottom part of plants (abaxial and adaxial leaf surface each one). For deposit evaluations, a cupric tracer was used and the amount of deposits was determined by a spectrophotometer. The second experiment was carried out in the same place and the treatments were of the same arrangement as the previous experiment, including control treatment (untreated plants). The spraying with triazole fungicide was realized in R2 and R5.2 growth stages of soybean with 142 l/ha spray volume. The nozzle angled of 30° combined with maximum air speed promoted the highest spray deposits on the soybean crop and influenced positively the control of the soybean Asian rust as well in the productivity of this crop.

Air-assistance and low volume application to control of asian rust on soybean crop

Currently, one of factors that cause the production cost increase of soybean crop is the pesticide application. The most important disease in soybean crop is Asian rust, caused by Phakopsora pachyrhizi Sydon & P. Sydon fungus, which can cause significant loss of the production. Therefore, this work aimed at evaluation of different spraying techniques on the spray deposits and some parameters of soybean crop: grain size, weight of 1 000 seeds and the crop productivity. Two experiments were carried out in the experimental area of FCA/UNESP (Faculdade de Ciencias Agronomicas/Universidade Estadual Paulista Julio de Mesquita Filho) - Botucatu, S P, Brazil, in soybean crop, Conquista variety, in the 2007/2008 season. In the first experiment, three air levels (0, 9 and 29 km/h of the air speed generated by fan) with flat fan nozzle XR 8002 with a spray volume of 130 l/ha were compared with a rotating nozzle - using low volume oily - LVO at 40 l/ha of spray volume. The second experiment was carried out under the same conditions as the previous experiment, including a control treatment (untreated plants). The disease severity was evaluated using a diagrammatic scale with a visual evaluation of the disease on 15 leaves of each plot. The grades varied between 0.6 and 78.5% of the disease severity. The use of air assistance when compared with the rotating system nozzle did not show significant differences for spray deposits on adaxial and abaxial surface of the leaves in bottom part of the plant. The air assistance with maximum air speed (29 km/h) increased the productivity with respect of the other treatments.

E-commerce and export promotion policies for small- and medium-sized enterprises: East Asian and Latin American experiences

Includes bibliography

E-commerce environment and trade promotion for Latin America: policy implications from East Asian and advanced economies' experiences

Includes bibliography

Export performance, technological upgrading and foreign direct investment strategies in the Asian newly industrializing economies: with special reference to Singapur

Includes bibliography

How optimal are the extremes?: Latin American exchange rate policies during the Asian crisis

Includes bibliography

Dynamics of foraging and recruitment behavior in the Asian subterranean termite Coptotermes gestroi (Rhinotermitidae)

The present study investigated the trail-following behavior of the subterranean termite Coptotermes gestroi (Wasmann Rhinotermitidae) under laboratory conditions. The results showed that workers were the first to initiate the exploration to the food source. When food was discovered they returned to the nest laying a trail for recruiting nestmates to the food source. In this situation, workers always traveled significantly faster when returning from the arenas. Both workers and soldiers were recruited to the food source; however, the soldier/worker proportion was higher during the first phase of the recruitment. When no food was available, the number of recruited nestmates and the speed on their way back to the nest were significantly lower. The results also showed that scout foragers always laid trail pheromones when entering into unknown territories, and that chemical signals found in the food could induce workers of C. gestroi to increase their travel speed. Copyright © 2012 Alberto Arab et al.

Economic relations between Latin America and the high-performing Asian developing economies

Includes bibliography