Bean production and fusarium root rot in diverse soil environments in Iran

摘要

The associations of Fusarium root rot (FRR) and yield variables with a number of soil characteristics were determined at pod maturity in 122 commercial bean fields in Zanjan, Iran. Mean pod and seed numbers per plant at a sand content level of 45-65% were lower than those at a level of 25-45%. Higher FRR index and fewer pods were detected in field soils with 30-48% silt content compared to 15-30% level. FRR index was higher in field soils treated with fungicides compared to non-treated soils. The lowest FRR index and highest yields occurred in the soils with the highest level of organic matter, 1.2-1.8%. The greatest FRR index and lowest yield levels were observed in non-nodulated beans compared to low- and high-nodulated beans. Soil pH and organic matter were negatively correlated with FRR variables. According to loadings for second principal component, the most relevant soil characteristic to FRR was pH, followed by organic matter, clay and sand content. There were spatial FRR correlations among bean fields. Organic matter was the most effective factor among the soil properties surveyed to improve bean productivity. This new information extends our knowledge over interactions between FRR, yield and various soil variables in commercial bean fields.