Pesticide residues in heterogeneous plant populations, a model-based approach applied to nematicides in banana (Musa spp.).
Nematicides are widely used to control plant-parasitic nematodes in intensive export banana (Musa spp.) cropping systems. Data show that the concentration of fosthiazate in banana fruits varies from zero to 0.035 g kg-1, under the maximal residue limit (MRL=0.05 mg kg-1). The fosthiazate concentration in fruit is described by a Gaussian envelope curve function of the interval between pesticide application and fruit harvest (preharvest interval). The heterogeneity of phenological stages in a banana population increases over time, and thus the preharvest interval of fruits harvested after a pesticide application varies over time. A phenological model was used to simulate the long-term harvest dynamics of banana at field scale. Simulations show that the mean fosthiazate concentration in fruits varies according to nematicide application program, climate (temperature), and planting date of the banana field. This method is used to assess the percentage of harvested bunches that exceed a residue threshold and to help farmers minimize fosthiazate residues in bananas.
Tixier
Philippe
P
CIRAD, UPR 26, PRAM - BP 214 - 97285 Lamentin Cedex 2 - Martinique, French West Indies, France. tixier@cirad.fr
Chabrier
Christian
C
Malézieux
Eric
E
D000969:Antinematodal Agents / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis; D005638:Fruit / Q000737:chemistry*; D028521:Musa / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis*; D010945:Plants, Edible / Q000737:chemistry*; D053778:Thiazolidines / Q000032:analysis
D000969:Antinematodal Agents; D009943:Organophosphorus Compounds; D010573:Pesticide Residues; D053778:Thiazolidines; C493102:fosthiazate