Morphological and biochemical responses of amaryllis (Hippeastrum vittatum) hybrid seedlings to bat guano and biochar amendments
1Department of Horticulture, College of Agricultural Engineering Sciences, University of Sulaimani, Sulaymaniyah city 46001, Kurdistan Region, Iraq. Corresponding e-mail: aram.hamarashed@univsul.edu.iq
DOI: https://doi.org/10.37855/jah.2026.v28i02.63
Seed-propagated Hippeastrum vittatum plants generally require three to five years to produce marketable flowering bulbs. The present study evaluated the effects of two rates of bat guano, 15 and 30 g per pot, and biochar, 3 and 6 g per pot, applied individually and in combination to one-year-old hybrid seedlings of H. vittatum. Compared to control seedlings, the treatments were not capable of improving any studied growth traits. The control seedlings had the highest root number (13.44), bulb weight (1.80 g), bulb size (1.82 cm3), leaf number (4.55), leaf length (31.87 cm), and leaf width (1.49 cm). In contrast, the combination of 30 g bat guano and 6 g biochar decreased root number (6.00), root length (3.67 cm), bulb weight (0.21 g), bulb size (0.13 cm3), leaf number (2.22), leaf length (10.54 cm), and leaf width (0.41 cm). Contrarily, the latter combination elevated root soluble sugar (211.89 µg g-1), root total carbohydrates (193.55 µg g-1), root starch (353.77 µg g-1), root total indoles (14.55 µg g-1), bulb total carbohydrates (260.64 µg g-1), leaf total flavonoids (31.48 µg g-1), leaf total proteins (2057.47 µg g-1), leaf total indoles (49.56 µg g-1). The same combination lowered leaf total carbohydrates (37.41 µg g-1), bulb starch (850.47 µg g-1), and root total proteins (225.19 µg g-1). These results indicate that the applied doses may indicate supra-optimal application rates to H. vittatum, thereby suppressing growth traits rather than enhancing them.
