Comparative Study of Induced Tetraploid and Diploid Gooseberry (Ribes grossularia L.): Growth, Stomatal, and Leaf Anatomical Traits

This study aimed to assess the phenotypic changes in tetraploids of two gooseberry genotypes (‘White Triumph’ and AGR9, 2n = 4x = 32) in relation to their diploid counterparts (2n = 2x = 16). Tetraploid plants of the ‘White Triumph’ cultivar were characterized by lower growth dynamics than the diploid (control) plants, with the exception of clone A7/2-4x, whose height was increased. Tetraploid plants from three AGR9 gooseberry clones exhibited enhanced growth dynamics compared to control plants. The stomatal length of tetraploid gooseberry genotypes was greater than that of the control, but the stomatal density was lower in tetraploids. The leaf blades and petiole lengths of the tetraploid, ‘White Triumph’, and AGR9 plants were significantly larger than those of their diploid counterparts. Almost all nine evaluated anatomical traits (upper and lower epidermis thickness, palisade and sponge tissue thickness, amount of intercellular spaces, midrib diameter, phloem and xylem thickness, and surface of midrib cells) of the leaves in tetraploids were significantly greater than those of their diploid counterparts. Principal component analysis (PCA) distinguished genotypes according to the ploidy level. The first two principal components explained 74.8% of the total variance, with PC1 (49.99%) representing the primary axis separating diploid (2x) and tetraploid (4x) genotypes. To the best of our knowledge, there have been no published reports on the phenotypic assessment of gooseberry tetraploids. The vigorous gooseberry tetraploids characterized in this study are likely the first of their kind to be reported.