Phosphite as phosphorus source to grain yield of common bean plants grown in soils under low or adequate phosphate availability

Abstract

The effects of foliar and soil applied phosphite on grain yield in common bean (Phaseolus vulgaris L.) grown in a weathered soil under low and adequate phosphate availability were evaluated. In the first experiment, treatments were composed of a 2 x 7 + 2 factorial scheme, with 2 soil P levels supplied as phosphate (40 e 200 mg P dm -3 soil), 7 soil P levels supplied as phosphite (0-100 mg P dm -3 soil), and 2 additional treatments (without P supply in soil, and all P supplied as phosphite). In the second experiment, treatments were composed of a 2 x 3 x 2 factorial scheme, with 2 soil phosphate levels (40 e 200 mg P dm -3 soil), combined with 3 nutrient sources applied via foliar sprays (potassium phosphite, potassium phosphate, and potassium chloride as a control), and 2 foliar application numbers (single and two application). Additional treatments showed that phosphite is not P source for common bean nutrition. Phosphite supply in soil increased the P content in shoot (at full physiological maturity stage) and grains, but at the same time considerably decreased grain yield, regardless of the soil phosphate availability. Foliar sprays of phosphite decreased grain yield in plants grown under low soil phosphate availability, but no effect was observed in plants grown under adequate soil phosphate availability. In general, foliar sprays of phosphate did not satisfactorily improve grain yield of the common bean plants grown under low soil phosphate availability. Index terms:Phaseolus vulgaris, tropical soil, foliar fertilizer, plant nutrition. RESUMOOs efeitos de fosfito aplicado via solo ou foliar sobre produção de grãos em feijoeiro (Phaseolus vulgaris L.), cultivado em um solo intemperizado sob baixa ou adequada disponibilidade de fosfato foram avaliados. No primeiro experimento, o delineamento consistiu de um esquema fatorial 2 x 7 + 2, sendo 2 doses de P fornecidas na forma de fosfato (40 e 200 mg P dm -3 de solo) x 7 doses de P no solo fornecidas na forma de fosfito (0-100 mg P dm -3 de solo), mais 2 tratamentos adicionais (sem fornecimento de P no solo, e todo o P fornecido na forma de fosfito). No segundo experimento, o delineamento consistiu de um esquema fatorial 2 x 3 x 2, com 2 doses de P no solo na forma de fosfato (40 e 200 mg P dm -3 de solo), combinados com 3 fontes de nutrientes aplicados via pulverização foliar (fosfito de potássio, fosfato de potássio, e cloreto de potássio como um controle), e 2 números de aplicações foliares (uma e duas aplicações). Os tratamentos adicionais evidenciaram que o fosfito não é uma fonte de P para a nutrição do feijoeiro. O fornecimento de fosfito no solo aumentou o teor de P na parte aérea (no estágio de maturidade fisiológica) e nos grãos, mas, ao mesmo tempo, consideravelmente reduziu a produção de grãos, independentemente da disponibilidade de fosfato no solo. As pulverizações foliares de fosfito diminuiram a produção de grãos em plantas cultivadas com baixa disponibilidade de fosfato no solo, mas esse efeito não foi observado em plantas cultivadas com...

In situ sampling and speciation method for measuring dissolved phosphite at ultratrace concentrations in the natural environment

“…This variation results from a partial conversion of P +III to P +V in the presence of ambient air. 10 However, P +III recovery remained stable without considerable bias even after the adsorbed P +III was stored for three days as either a binding gel or eluent, as indicated in Figure 2-C. After 30 days of refrigeration, P +III recoveries of the retrieved binding gels and eluent decreased over time with a 54.8% and 78.7% retention, respectively.…”

“…Several studies have also reported that P +III can be directly or indirectly utilized by plants, 9,10 microbes, 5,11 and algae. 12 However, its toxicity that P +III is most recognized for, and this is the primary concern for environmental monitoring programmes.…”

Review of Phosphite as a Plant Nutrient and Fungicide

“…Ávila [80] grew common bean (Phaseolus vulgaris) in low and adequate soil Pi fertilized with increasing Phi (0 → 100 mg P dm −3 soil). In low Pi soil, Phi reduced plant growth and grain yield only when Phi was ≥25 mg P dm −3 soil; Phi toxicity symptoms were also observed.…”

Phosphorus and potassium fertilization increase common bean grain yield in Mozambique

“…The common bean is a high demand plant for nutrients, and thus low natural soil fertility is one of the major factors that can limit productivity of this crop in tropical regions (Ávila et al, 2012;Fageria & Nascente, 2014;Argaw et al, 2015;Silva et al, 2016). Therefore, to avoid soil impoverishment and reduced productivity over time, it is necessary to replace at minimum the quantity of nutrients exported by the grains.…”