In endosperms of Maize and Pinus the ploidy levels are

In endosperms of Maize and Pinus the ploidy levels are Triploid and haploid.
The embryo cells are diploid and made of one paternal and one maternal haploid genome, whereas the endosperm is constituted of triploid cells made of two maternal haploid genomes and one paternal haploid genome.
In gymnosperms like pinus, there is no double fertilization and the endosperm is formed before fertilization. The haploid megaspore undergoes repeated divisions and forms a haploid endosperm.