Photosynthesis Inhibiting Effects of Pesticides on Sweet Pepper Leaves.

Miguel Giménez–Moolhuyzen,Eduardo Crisol–Martínez,Pilar Lorenzo–Mínguez,Tomás Cabello,Jan Van Der Blom

doi:10.3390/insects11020069

Abstract

Although a large number of pesticides of different compositions are regularly used in agriculture, the impact of pesticides on the physiology of field crops is not well understood. Pesticides can produce negative effects on crop physiology―especially on photosynthesis―leading to a potential decrease in both the growth and the yield of crops. To investigate these potential effects in greenhouse sweet peppers, the effect of 20 insecticides and 2 fungicides (each sprayed with a wetting agent) on the photosynthesis of sweet pepper leaves was analyzed. Among these pesticides, nine caused significant reductions in photosynthetic activity. The effects were observed in distinctive ways—either as a transitory drop of the photosynthetic-rate values, which was observed at two hours after the treatment and was found to have recovered after 24 h, or as a sustained reduction of these values, which remained substantial over a number of days. The results of this study suggest that the production of a crop may substantially benefit when the frequent use of pesticides can be substituted with alternative pest control methods (e.g., biological control). Our results advocate further investigation of the potential impact of pesticides, either alone or in combination, on the photosynthesis of crop plants.

Highlights

After 60 years of wide-scale commercial use and despite the numerous negative consequences associated with pesticide treatments [1,2,3,4,5,6,7], pesticides still remain the quintessential strategy of crop management in most agricultural systems, with over 2.7 million metric tons used yearly, on a global scale [8]
The present study was initiated to quantify the short-term effect of pesticide treatments on the photosynthesis of sweet pepper leaves. It was performed in Almeria when Integrated Pest Management (IPM) adoption was in its initial stage [31]
This method was found to be better than leaf dipping, because the latter did not provide a homogeneous distribution of insecticide solution droplets on the leaf

Summary

Introduction

After 60 years of wide-scale commercial use and despite the numerous negative consequences associated with pesticide treatments [1,2,3,4,5,6,7], pesticides still remain the quintessential strategy of crop management in most agricultural systems, with over 2.7 million metric tons used yearly, on a global scale [8]. Pesticides may impact the crop physiology through various disruptions, such as perturbation in the development of the reproductive organs, growth reduction, and alteration of the carbon and/or nitrogen metabolism, leading to a lower nutrient availability for plant growth. These disruptions will partly depend on the type of pesticide used [10]. The present study was initiated to quantify the short-term effect of pesticide treatments on the photosynthesis of sweet pepper leaves. It was performed in Almeria when Integrated Pest Management (IPM) adoption was in its initial stage [31]. The composition and/or commercial names of a number of products may have been subject to alterations

Materials and Methods

Meanwith

Findings

Discussion