Aspects of Rainfastness of Cultar (Paclobutrazol) on Glasshouse Grown Apple and Peach

Reactivity of the Plant Growth Regulator Paclobutrazol (Cultar) with Two Tropical Soils of the Northeast Semiarid Region of Brazil

“…Recent studies on the contamination of superficial waters and aquifers of the São Francisco River Valley demonstrated the potential, ample presence of PBZ, evidencing this chemical as a major contaminant of aquifers in this region (EMBRAPA, 2001; Ferracini et al, 2001). Indeed, after application, PBZ is partially taken up by plants (Attiya et al, 1983; Orzolek and Kaplan, 1988; Singh and Ram, 2000; Sharma and Awasthi, 2005) and quite quickly transported to the underlying aquifer by rainfall washing (Jones et al, 1989; Salazar‐Garcia and Vazquez‐Valvidia, 1997) and infiltration. The first point is quite well documented, as plant uptake of PBZ is important and known to be dependent on rain washing efficiency when applied as a foliar spray (Jones et al, 1989; Salazar‐Garcia and Vazquez‐Valvidia, 1997).…”

“…Indeed, after application, PBZ is partially taken up by plants (Attiya et al, 1983; Orzolek and Kaplan, 1988; Singh and Ram, 2000; Sharma and Awasthi, 2005) and quite quickly transported to the underlying aquifer by rainfall washing (Jones et al, 1989; Salazar‐Garcia and Vazquez‐Valvidia, 1997) and infiltration. The first point is quite well documented, as plant uptake of PBZ is important and known to be dependent on rain washing efficiency when applied as a foliar spray (Jones et al, 1989; Salazar‐Garcia and Vazquez‐Valvidia, 1997). Surprisingly and despite the huge amounts of PBZ applied to crops and the groundwater contamination risk associated with PBZ‐like molecules (Voon et al, 1992; EMBRAPA, 2001; Ferracini et al, 2001; Paraíba et al, 2003; Armas et al, 2005), its fate and toxicity is still unclear and poorly documented.…”