Adansonia digitata germination tests. Elephants or heat: what causes scarification of seed to facilitate germination?

Botanical Studies

Table 4 Acid treatment: Relative germination rate of Adansonia digitata seeds in percentage

Treatment	0–2 weeks	3–4 weeks	5–6 weeks	7–8 weeks	9–10 weeks
H₂SO₄ for 5 min	0	0	0	0	0
H₂SO₄ for 10 min	0.3^a	5.7^a	1^a	0^a	0.3^a
H₂SO₄ for 15 min	2	12	0	0	0
HCl for 1 h, pH 2	0	0	0	0	0
HCl for 1 h, pH 3	0	0	1	1	0
HCl for 2 h, pH 2	0	1	0	0	0
HCl for 2 h, pH 3	0	2	0	0	0
Elephants´ digestion, germinating in soil	0.7^a	1.7^a	0^a	0.3^a	0^a
Elephants´ digestion, germinating in elephants´ faeces	0	1	0	0	0

Numbers marked with ^aare the average of the germination tests (2017, 2018, 2019) the remaining numbers are obtained in the test sets in 2018 or 2019