Table 3.

Effects on pollen removal of successive stamen movements in Ruta graveolens flowers

Floral type	Manipulations on the stamen movement	No. of pollen removed (mean ± s.d.)*
		2010	2011
Pentamerous	Control (naturally moved)	6310·61 ± 158·02a	5258·76 ± 43·15a
	Immobilized	4112·27 ± 219·57b	3398·68 ± 305·93c
	Interference by the former stamen	5210·61 ± 489·22ab	4685·67 ± 118·64b
Tetramerous	Control (naturally moved)	14 740·56 ± 92·30a	6866·05 ± 16·23a
	Immobilized	13 098·89 ± 307·92b	4561·20 ± 455·01c
	Interference by the former stamen	12 955·33 ± 300·01b	6131·28 ± 176·27b

* Different letters indicate significant differences at P < 0·0001 (Student's t-test).