The β-carotene content, and therefore the vitamin A value, of orangefleshed
sweet potato vary depending on cultivation practices and harvesting
time. A low irrigation treatment was shown to result in 15% to 34%
higher β-carotene content than the optimal irrigation treatment. However,
itwas noted that increasedwater application resulted in a two-fold increase
in β-carotene yield per unit area (nutritional productivity). The
intermediate (60%) irrigation treatment provided the best combination
of β-carotene yield and water productivity (11.5 to 16.3 g β-carotene
ha−1 mm−1 water applied). Meanwhile β-carotene content was 14%
higher for both intermediate (50%) and high (100%) fertilizer treatments,
compared to the 0% fertilizer treatment. The β-carotene yield increased
two-fold at the intermediate and four-fold at the high fertilization treatment.
Furthermore harvesting time also affects the β-carotene content;
harvesting at four, five and six months after planting at the rural village
showed gradual increases in β-carotene content; while no change was
observed under optimal conditions (Laurie, Fab