Which of the tissue culture will form a triploid plant

The correct answer is endosperm.

Let us understand the ploidy levels of different plant tissues to determine which one forms a triploid plant when cultured:

1. Understanding Ploidy Levels:
Ploidy refers to the number of sets of chromosomes in a cell.

• Haploid ($n$): Contains one single set of chromosomes. Tissues derived from gametes or spore-producing structures prior to fertilization are usually haploid.
• Diploid ($2n$): Contains two sets of chromosomes, resulting from the fusion of two haploid gametes. Most somatic plant tissues (like ovule tissue/nucellus) are diploid.
• Triploid ($3n$): Contains three sets of chromosomes.

2. Analyzing the Given Tissues:

• Endosperm ($3n$): In angiosperms (flowering plants), the endosperm is formed through the process of double fertilization, specifically via triple fusion (the fusion of one haploid male gamete with two haploid polar nuclei). As a result, endosperm tissue is triploid ($3n$). Culturing endosperm tissue via tissue culture technique yields triploid plants.
• Megaspore ($n$): A megaspore is produced through meiosis and is haploid. Tissue culture of a megaspore leads to a haploid plant.
• Pollen ($n$): Pollen grains represent the male gametophyte and are haploid. Pollen culture gives rise to haploid plants.
• Ovule ($2n$): The vegetative/maternal tissues of the ovule (such as the integuments and nucellus) are diploid. Culturing ovule tissue generally results in diploid plants.

Therefore, tissue culture of the endosperm will form a triploid plant.