* Corresponding authors

^a Interdisciplinary Science and Engineering Laboratory, University of Delaware, Newark, DE 19716, USA
E-mail: jaisi@udel.edu
Fax: +1 302 831 0605
Tel: +1 302 831 1376

^b Department of Soil Science, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP 13418-900, Brazil
E-mail: mealves.esalq@usp.br
Tel: +55 19 3429 4189

^c Nanotechnology National Laboratory for Agriculture, Brazilian Agricultural Research Corporation, São Carlos, SP 13560 970, Brazil

^d Department of Exact Sciences, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP 13418-900, Brazil