Table 1.

Percentage germination of S. hermonthica seeds after exposure to GR24 (0.1 mg l⁻¹) or to sorghum root exudates

	S-35		CK60-B
Treatment	Harvest 1	Harvest 2	Harvest 1	Harvest 2
GR24	52.6	61.7	52.6	61.7
—AM—P	13.3	48.5	6.2	41.1
—AM+P	12.3	49.8	5.7	52.3
+AM—P	1.6	2.5	1.3	29.1
+AM+P	1.4	0.9	4.0	26.4
Mann-Whitney U-test
Mycorrhiza	**	**	n.s.	**
Phosphorus	n.s.	n.s.	n.s.	n.s.

Root exudates were obtained from two sorghum cultivars (S-35, CK60-B) grown for 24 (harvest 1) or 45 (harvest 2) days with AM fungal inoculation (−AM = no inoculation; +AM = addition of 50 g per pot) and/or P (−P = no addition of P fertilizer; +P = addition of the equivalence of 30 kg ha-1 of triple superphosphate). Values are means of five replicates. Mann-Whitney U-test: n.s. not significant (P > 0.05);

^**P < 0.01.