Pesticides Shown To Reduce Soil Fertility
Friday, June 8th, 2007(Beyond Pesticides, June 8, 2007) New research shows that pesticides can reduce the efficiency of nitrogen-fixing plants, impacting soil fertility and ultimately reducing crop yields. The insecticides methyl parathion, DDT and pentachlorophenol were among the chemicals found to inhibit or delay the symbiotic relationship between the legume alfalfa and rhizobia bacteria, which is crucial to nitrogen fixation. Legume crops are often cultivated to help replenish the vital soil nutrient nitrogen (N), but legumes cannot achieve this on their own — Rhizobium bacteria interacts with legumes to convert atmospheric N to nutrient compounds utilizable by plants. Legumes like alfalfa and soybeans are often included in crop rotations due to this beneficial relationship. Nitrogen fixation resulting from the symbiotic relationship between leguminous plants and species of Rhizobium bacteria is an ecological service estimated to be equivalent to $10 billion worth of synthetic N fertilizer annually. Symbiotic nitrogen fixation (SNF) reduces the need for synthetic fertilizers, which cause environmental problems such as impaired water quality. Acknowledging that SNF is both initiated and maintained by chemical signals between the host plant and the beneficial bacteria, the research team postulated that natural and synthetic chemicals could disrupt these signals. The study shows “previously undescribed in […]
