Effect of Surface Application of Polyvinyl Alcohol on Phosphorus Losses in Runoff and on Corn Growth

Abstract

Phosphorus loading in surface water bodies due to runoff from cropland is a major concern with respect to water quality. Losses of water, soil, and different forms of P, from five runoff plots treated with polyvinyl alcohol (PVA), were comparet do losses from five untreated plots. The plots were on a loam soil with 6.5 to 9.5% slopes. The effect of a single application of PVA was observed over 2 yr under natural rainfall. During the first year after application of PVA, runoff and soil losses were reduced by 56 and 80%, respectively. Extractable P, total P, and dissolved molybdate‐reactive P (DMRP) losses were reduced by 79, 75, and 64%, respectively. Corn (Zea mays L.) grain yield on the treated plots was 12% higher than on the control plots. All the above differences were statistically significant. During the second year, in which no tillage occurred and no PVA was applied, total P and DMRP losses were reduced by 42 and 40%, respectively, by the PVA treatment of the previous year. Although runoff and soil loss were lower for the treated plots, these differences were not significant at P = 0.05 (P values were 0.11 and 0.10, respectively.

Effect of polyvinyl alcohol on in vitro rooting capacity of shoots in pear clones (Pyrus communis L.) of different ploidy

“…Rooting methods for other Pyrus species that had been published (Bertazza et al 1995;Barros et al 2005;Dolcet-Sanjuan et al 1990;Liu et al 2004;Luo et al 2006;Marino 1988;Marks and Simpson 2000;Shibli et al 1997) were not effective for the polyploid clones in our preliminary experiments. It had been reported that PVA had been used for seed coating or pretreatment seed to improve seed germination, seedling growth or resistance to salt (Lin et al 2003;Guo et al 1989;Hong and Zhao 1997;Ruan and Xue 2002;Xiong 1998), to increase chlorophyll content in peas (Czeczuga and Nowak 1962), or used in soil to reduce runoff and soil losses (Marsh and Groenevelt 1992) and to stabilize soil (Stefanson 1973;Oades 1976). Recently there have been reports that PVA could be used to reduce vitrification in plant tissue culture, improve root number and root length in jujube ) and improve rooting percentage in woad (Zhang et al 2007).…”