Review of Phosphite as a Plant Nutrient and Fungicide

• Main Authors: John L. Havlin, Alan J. Schlegel
• Format: Article
• Language: English
• Published: MDPI AG 2021-08-01
• Series: Soil Systems
• Subjects: phosphorus; phosphite; plant disease; plant nutrition; genetics; soil chemistry
• Online Access: https://www.mdpi.com/2571-8789/5/3/52

Phosphite (<i>Phi</i>)-containing products are marketed for their antifungal and nutritional value. Substantial evidence of the anti-fungal properties of <i>Phi</i> on a wide variety of plants has been documented. Although <i>Phi</i> is readily absorbed by plant leaves and/or roots, the plant response to <i>Phi</i> used as a phosphorus (P) source is variable. Negative effects of <i>Phi</i> on plant growth are commonly observed under P deficiency compared to near adequate plant P levels. Positive responses to <i>Phi</i> may be attributed to some level of fungal disease control. While only a few studies have provided evidence of <i>Phi</i> oxidation through cellular enzymes genetically controlled in plant cells, increasing evidence exists for the potential to manipulate plant genes to enhance oxidation of <i>Phi</i> to phosphate (<i>Pi</i>) in plants. Advances in genetic engineering to sustain growth and yield with <i>Phi</i> + <i>Pi</i> potentially provides a dual fertilization and weed control system. Further advances in genetic manipulation of plants to utilize <i>Phi</i> are warranted. Since <i>Phi</i> oxidation occurs slowly in soils, additional information is needed to characterize <i>Phi</i> oxidation kinetics under variable soil and environmental conditions.