raster - Spplot SpatialPolygonDataFrame and SpatialGridDataFrame

I have to plot in the same graph something like this:

Then, I have elements from SpatialPolygonDataFrame class and others elements from SpatialGridDataFrame class. When I try to plot them in the same graph only get this error:

Error in `[[<-.data.frame`(`*tmp*`, i, value = c(52.6195687909829, 52.6845097109409,  : 
  replacement has 64 rows, data has 672. 

However, I converted all elements to SpatialPolygonDataFrame class, but it does not work.

I've watched the data and I think that the problem is the size of the elements (row, columns) but I'm not sure. I do not how to do it.

This is a example of my routine.

# Interpolation kriging
k_066_1617H <- krige(data066_1617H$Vtec~1,locations = data066_1617H,newdata = gridpolygon2,model = Ajuste2) 

class(k_066_1617H)

#[1] "SpatialPolygonsDataFrame"
#attr(,"package")
#[1] "sp"

Then, read a TIFF file

land <- readGDAL("image.tif")  
class(land)

#[1] "SpatialGridDataFrame"
#attr(,"package")
#[1] "sp"

land <- Grid2Polygons(land) # Transform into SpatialPolygonDataFrame


class(land)

#[1] "SpatialPolygonsDataFrame"
#attr(,"package")
#[1] "sp"

Construct a vector with land and k_066_1617H for plot with spplot

zn.k_066_1516H = land


zn.k_066_1617H = k_066_1617H
zn = land
zn[["a"]] = land[["z"]]
zn[["b"]] = zn.k_066_1617H[["var1.pred"]]

Here, is the problem. Maybe the size of elements is the problem.

land has 28 rows and 24 columns and k_066_1617H has 3752 rows.

spplot(zn, c("a","b"),
            main = "Santander, VTEC día 066",
            #names.attr = c("Prueba","18 - 19", "16 - 17"),

            lty=0,
            lwd=7,
            sp.layout = c('sp.points', santos.coord, col='red', pch=19),
            contour=TRUE, 
            col='black',
            pretty=TRUE,
            scales=list(draw = TRUE),
            labels=TRUE)