Use the zebra widget:
$(document).ready(function () {
var grid = "#" + "<%= gvwLand.ClientID %>";
$(grid).tablesorter({
widgets: ['zebra'],
headers: {
0: { sorter: false },
9: { sorter: false }
}
});
$('.tablesorter tr').mouseover(function () {
$(this).addClass("over");
});
$('.tablesorter tr').mouseout(function () {
$(this).removeClass("over");
});
});