Impact of sulfur dust application on the abundance of two important coccinellid predators in marrow fields

Bulletin of the National Research Centre

Table 3 Population densities of Stethorus punctellium adults in untreated and sulfur-treated marrow cultivations

Inspection periods (hours)	First area		Second area	F value (1)
	Average number of adults/50 plants/plot ± SE
	Treated plot	Untreated plot	Untreated area
(−) 0	6.75 ± 2.06 aA	6.50 ± 2.22 aB	4.75 ± 0.48 aBC	0.380^NS
(+) 2	1.25 ± 0.75 bB	4.50 ± 1.32 aB	4.00 ± 0.71 abC	4.267*
(+) 12	0.00 ± 0.00 bB	8.75 ± 1.25 aB	6.25 ± 0.75 aABC	28.676**
(+) 24	0.75 ± 0.25 bB	7.00 ± 1.58 aB	4.25 ± 1.18 aC	7.437**
(+) 48	2.25 ± 0.85 bB	8.25 ± 1.31 aB	7.25 ± 1.44 aAB	6.857*
(+) 72	2.00 ± 0.41 bB	7.25 ± 1.11 aB	8.00 ± 0.82 aA	15.545**
(+) 7 days	2.50 ± 0.87 bB	7.00 + 1.22 aB	6.75 ± 0.63 aABC	7.252**
F value (2)	5.147**	0.859^NS	2.957*

Before application (−), after application (+), df 1 = 2, 9, df 2 = 6, 21. Data in rows with the same small letters are not significantly different (P value at 5%). Data in columns with the same capital letters are not significantly different (P value at 5%). *Significant, **highly significant, and NS insignificant