Ponencias

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14396

Examinar

Mostrando 1 - 2 de 2

Nematology in Central American countries, a general overview of the present situation
(50TH ANNUAL MEETING OF NEMATOLOGIST OF TROPICAL AMERICA (ONTA 2018), 2018-08) Chaverri Fonseca, Fabio; Bravo, Virya; Ramírez, Fernando; Berrocal, Silvia; Orozco, Martha; Córdoba, Leonel
Pesticide use in Central American agriculture has been promoted as an important tool for development since decades, despite in many cases being a hazardous technology for human health and the environment. At the same time that a number of industrialized countries are undertaking significant steps to reduce pesticide consumption, developing countries are becoming a more important marketing target. In addition to high volume and toxicity of pesticides in use in Central America, tropical conditions and usage practices can also increase environmental and human health risks. Collateral damage of pesticides has been attributed primarily to insufficient regulation and failure on technical assistance of pesticide users in developing countries, and it has been assumed that strengthening of regulations and education to users would lead to an acceptable level of pesticide safety. Recent studies by the IRET (National University of Costa Rica), estimate that Central America import around 1600 ton of nematicides per year, which accounts for about 5% of the total import of pesticides in the area. An important issue is that the agricultural area remains almost the same size on the last 5 years, around 7.6 x 106 ha (FAO-STAT). The use of chemical nematicides remains high on Central American region, especially for exportation crops with intensive agricultural practices. The study of the water bodies downstream of these agricultural lands shows consistent results of pesticide concentrations and effects on aquatic organism and communities. Many imported chemical nematicides are of special environmental and human health concerns, including 1,3-D, terbufos, cadusafos, ethoprop, among others. Some of them are included on the Hardly Hazardous Pesticides list (HHP). Recent studies among farmers show increased knowledge and risk awareness without substantial changes in pesticide handling. Continuous poisonings and environment contamination with pesticides were reported to the surveillance systems. Alternative approaches are needed, and successful examples exist like Integrated Pest Management and biological control programs. Although there are successful cases of substitution of dangerous pesticides and alternatives, there are still failures in implementation such as lack of plant parasitic nematology extension, research services and educational programs. It is necessary to make profound changes in international and national agricultural policies and steer towards sustainable agriculture, hazardous substances as the chemical nematicides require different levels of control in their manufacturing, transportation, storage, handling, use and disposal to manage the potential risk properly, especially in the Central American area, one of the most vulnerable zone to the effects of climate change around the world The main emerging concern on Central American region is the reduction in some companies of personnel specialized in nematology. This concern is based on the next future needs, especially because the main goal of this topic seems to be to develop innovative research projects, tools and technologies for nematode surveillance over large geographic regions, applicable or adaptable to multiple crops and diseases/pests complex.
SUPPRESSION OF THE ROOT-KNOT NEMATODE (MELOIDOGYNE SP.) WITH CHEMICAL-ORGANIC PRODUCTS IN ONION CROP.
(50TH ANNUAL MEETING OF NEMATOLOGIST OF TROPICAL AMERICA (ONTA 2018), 2018-08) Cabrera-Hidalgo, A. J.; Marban-Mendoza; Chaverri Fonseca, Fabio
The management of root–knot nematodes is a complex process in any farming system of susceptible plants, since most of the products not fumigants do not have current registration for vegetables. In the last five years, very promising results were obtained with the application of fluensulfone, a product of the fluoroalkenyle group, and offering a replacement alternative to the traditionally used chemical nematicide and generate high detrimental impact over the environment and human health. We evaluated three doses of FSF (175, 2.0 and 2.25 L / ha), one of fenamiphos (7.0 L / ha) and untreated plants were included as controls. All treatments were established under a design of complete blocks with three replications randomly. The fluensulfone in doses of 2 to 2.25 L significantly reduced populations and damage caused by Meloidogyne sp. 60 DAS, plots treated with FSF in doses of 2 to 2.25 L.ha-1 and fenamiphos (7 L.ha-1) showed lower damage with 6.33-9.00% of damping on average, reducing the damping in onion plants by more than 260%. The dose of 1.75 FSF L.ha-1 reduced the damage in a 114% compared to control plants. Commercial bulbs production was greater in plots treated with FSF (2.0-2.25 L.ha-1) and fenamiphos (7 L.ha-1) with 5.9, 6.0 and 5.9 kg.m-2, increasing performance by 11-14% relative to the control, respectively. The main advantages of the FSF is that it acts as a true nematicide, its control effect can last up to 60 days with low populations, is applied through the irrigation system prior to planting, and is not phytotoxic at the crop if it is applied following the instructions on the label.

Examinar

Examinando Ponencias por Materia "Nematology"