The Influence of Form and Rate on the Efficacy of Matrix-Based Fertilizers to Reduce Nutrient Leaching

Table 4

Total amount of NH₄, NO₃, total phosphorus (TP), and dissolved reactive* phosphorus (DRP) leached from sandy loam and loam soils and shoot and root dry weight and arbuscular mycorrhizal infection of St. Augustine grass receiving low, moderate, and high rate of matrix-based fertilizer 1 (MBF4), matrix-based fertilizer 3 (MBF5), and the slow release fertilizer Osmocote (14-14-14) (SRF) over 126 days.

Fertilizer	Rate	Nitrogen	Phosphorus	DRP	TP	NO3	NH4	Shoot	Root	Total	Myc
		Applied	Applied					Weight	Weight	Weight
		kg ha^−1		mg element L^−1 water				g			%
Fertilizer not applied (Control)		0	0	3.86^(e)	7.16^(d)	8.45^(f)	0.83^(e)	21.82^(d)	16.35^(b)	38.18^(e)	70^(a)
Matrix Based Fertilizer 1 (MBF4)	Low	243	262	3.75^(e)	6.60^(d)	12.77^(f)	0.39^(e)	25.10^(c)	16.69^(b)	41.78^(d)	80^(a)
Matrix Based Fertilizer 3 (MBF5)	Low	121	235	3.44^(e)	6.07^(d)	5.73^(f)	0.17^(e)	28.27^(c)	16.41^(b)	44.69^(d)	75^(a)
Osmocote 14-14-14 (SRF)	Low	267	255	12.98^(c)	11.90^(bc)	173.77^(c)	4.53^(c)	50.23^(b)	16.74^(b)	66.97^(bc)	60^(a)
Matrix Based Fertilizer 1 (MBF4)	Moderate	486	524	3.91^(e)	6.30^(d)	30.44^(e)	0.91^(e)	30.16^(c)	17.28^(b)	47.44^(d)	63^(a)
Matrix Based Fertilizer 3 (MBF5)	Moderate	242	470	3.24^(e)	5.42^(d)	7.40^(f)	0.24^(e)	33.11^(c)	17.01^(b)	50.12^(d)	73^(a)
Osmocote 14-14-14 (SRF)	Moderate	534	510	20.91^(b)	17.47^(b)	258.16^(b)	51.75^(b)	54.68^(b)	16.88^(b)	71.56^(b)	79^(a)
Matrix Based Fertilizer 1 (MBF4)	High	729	786	7.05^(d)	8.20^(cd)	72.81^(d)	3.61^(d)	38.99^(c)	17.29^(b)	56.28^(cd)	75^(a)
Matrix Based Fertilizer 3 (MBF5)	High	363	705	7.16^(d)	5.38^(d)	11.07^(f)	0.86^(e)	30.33^(c)	16.81^(b)	47.15^(d)	74^(a)
Osmocote 14-14-14 (SRF)	High	801	765	27.29^(a)	23.28^(a)	402.68^(a)	114.70^(a)	69.73^(a)	18.65^(a)	88.02^(a)	82^(a)

(a)In each column, values followed by the same letter are not significantly different as determined by the least square means test (𝑃≤.05;𝑛=6). (b)Statistical comparisons of parameters in water are presented with regard to fertilizer × rate because interactions of fertilizer × rate × soil × week sampled, fertilizer × rate × soil, and fertilizer × rate × week sampled were not significant in the GLM model (𝑃≤.05;𝑛=6). (c)Percent (%) of fine roots infected with arbuscular mycorrhizae.