Biodegradation of Agricultural
Fungicides
Hugh D. Sisler
6. 1. INTRODUCTION
6
Most natural organic matter decomposes rapidly to CO2 and water under conditions favorable for biodegradation. However, when unfavorable conditions
prevail, such as anaerobic environments, extreme pH, or very low temperature,
natural organic matter persists for very long periods and material such as wood
and even whole animal bodies is conserved for centuries (Kaars Sijpesteijn et
al., 1977). While the rate of degradation of many organic pesticides is similar
to that of natural materials, the situation with pesticides is more complicated
because some molecules or their metabolites may persist even under the most
favorable conditions for biological attack. A vast number of different situations
prevail in respect to pesticide degradation in the environment. We should strive
to develop pesticides which degrade as readily as natural products; however,
even if this goal is attained, pesticide molecules or their metabolites may still
persist under conditions unfavorable for biodegradation. Biodegradability, therefore, must be defined in terms of the environment to which a pesticide is subjected.
In the following sections some of the properties and degradation products
of a few of the more important agricultrual fungicides will be discussed. The
Hugh D. Sisler • Department of Botany, University of Maryland, College Park, Maryland 20742.
This is contribution No. 5638, Publication No. A2599, from the University of Maryland Agricultural
Experiment Station.
133
Fungicides
Hugh D. Sisler
6. 1. INTRODUCTION
6
Most natural organic matter decomposes rapidly to CO2 and water under conditions favorable for biodegradation. However, when unfavorable conditions
prevail, such as anaerobic environments, extreme pH, or very low temperature,
natural organic matter persists for very long periods and material such as wood
and even whole animal bodies is conserved for centuries (Kaars Sijpesteijn et
al., 1977). While the rate of degradation of many organic pesticides is similar
to that of natural materials, the situation with pesticides is more complicated
because some molecules or their metabolites may persist even under the most
favorable conditions for biological attack. A vast number of different situations
prevail in respect to pesticide degradation in the environment. We should strive
to develop pesticides which degrade as readily as natural products; however,
even if this goal is attained, pesticide molecules or their metabolites may still
persist under conditions unfavorable for biodegradation. Biodegradability, therefore, must be defined in terms of the environment to which a pesticide is subjected.
In the following sections some of the properties and degradation products
of a few of the more important agricultrual fungicides will be discussed. The
Hugh D. Sisler • Department of Botany, University of Maryland, College Park, Maryland 20742.
This is contribution No. 5638, Publication No. A2599, from the University of Maryland Agricultural
Experiment Station.
133