Sporophytes are dependent on gametophytes is true for the bryophytes.
Bryophytes are photosynthetic land plants. They are non-vascular as they are devoid of vascular tissue. The life cycle of bryophyte is consists of alternating generations between haploid (n) gametophytes stage and diploid (2n) sporophyte stage. During the gametophytic stage, haploid male gametes are formed in a specialized structure called antheridium and haploid female gametes are formed in a specialized structure called archegonium.
The male gametes or sperms are biflagellated. They need water to reach the archegonium to fertilize with eggs. The two haploid gametes fuse to form a diploid zygote (2n) is formed. The zygote grows inside the archegonia and later developed into a diploid sporophyte. The mature sporophytes remain attached to the female gametophyte and produced haploid spores inside the sporangium through meiosis. Under favorable conditions, spores are dispersed and grown to new gametophytes. The sporophytes are not photosynthetic and directly depend on the female gametophytes for their nutrition. Therefore, they are parasitic in nature.