Explanation

Endosperm is formed by the fusion of two polar nuclei or their fusion product (secondary nucleus) with second male gamete. A diploid female plant will produce a haploid egg and two haploid polar nuclei. The chromosome number in the male gamete produced from a tetraploid male plant will be half of its mate parent (tetraploid male) i.e., male gametes will be diploid. Hence, these plants when crossed, produce triploid zygote (fusion product of diploid male gamete with haploid egg) and tetraploid endosperm (fusion product of diploid male gamete and diploid secondary nucleus). [image:10_image5.jpeg]