Promotion of host plant growth and infection of roots with arbuscular mycorrhizal fungus Gigaspora margarita by the application of peat

Figures & data

Table 1 Physical and chemical properties of the soil medium

	Volume ratio (%)	MWHC (g kg^−1)	Bulk density (g cm^−3)	P2O5 (mg kg^−1)	Total N (g kg^−1)	Total organic C (g kg^−1)
Peat	–	4225.0	0.16	56.0	29.80	469.4
0% peat^†	–	302.0d	1.33a	12.0c	0.08e	0.5e
2.5% peat^†	13.2	350.0cd	1.27b	12.9c	0.47d	6.8d
5% peat^†	23.8	384.7c	1.18c	13.8bc	1.01c	15.7c
10% peat^†	39.7	482.0b	1.05d	15.6b	1.71bc	27.4bc
15% peat^†	51.1	641.0a	0.93e	17.4ab	2.22b	38.3b
20% peat^†	59.7	671.3a	0.85f	19.2a	3.32a	54.1a
^†These values correspond to 0, 25, 50, 100, 150 and 200 g kg^−1 of peat added to Masa soil. For the culture media (0, 2.5, 5, 10, 15 and 20%), means followed by the same letter are not significantly different according to Tukey tests (P < 0.05). MWHC, maximum water-holding capacity.

Figure 1  Shoot fresh weight of (a) non-inoculated plants and (b) inoculated plants at each harvest time. Bars represent standard deviations of the means of three replicates. Peat addition rate: 0% (–⧫–), 2.5% (–▪–), 5% (–▴–), 10% (--×--), 15% (–×–) and 20% (–•–) (w/w).

Figure 2  Total root length of inoculated plants. Bars represent standard deviations of the means of three replicates. Differences among the levels of peat addition were determined using an anova (P = 0.58, 0.04, 0.036 and 0.16 at 40, 60, 90 and 120 days, respectively). Peat addition rate: 0% (–⧫–), 2.5% (–▪–), 5% (–▴–), 10% (--×--), 15% (–×–) and 20% (–•–) (w/w).

Figure 3  Root colonization at each harvest time. Bars represent standard deviations of the means of three replicates. Differences among the levels of peat addition were determined using an anova (P = 0.03, 0.001, 0.001 and 0.001 at 40, 60, 90 and 120 days, respectively). Peat addition rate: 0% (–⧫–), 2.5% (–▪–), 5% (–▴–), 10% (--×--), 15% (–×–) and 20% (–•–) (w/w).

Figure 4  Spore number per pot at each harvest time. Bars represent standard deviations of the means of three replicates. The differences among the levels of peat addition were determined using an anova (P = 0.01, 0.001, 0.04 and 0.001 at 40, 60, 90 and 120 days, respectively). Peat addition rate: 0% (–⧫–), 2.5% (–▪–), 5% (–▴–), 10% (--×--), 15% (–×–) and 20% (–•–) (w/w).