Table 2.

Primary root growth pattern and habitat of species from three Cactaceae subfamilies (preliminary data)

Subfamily	Species	Root growth pattern	Habitat
Opuntioideae	Opuntia puberula Pfeiff.	D/I	SA
	O. streptacantha Lem.	D/I	SA
	O. xoconostle syn. O. matudae Scheinvar	D/I	SA
	O. tehuacana S.Arias & U.Guzmán	D/I	SA
	Maihueniopsis darwinii (Hensl.) F. Ritter	D/I	A
	M. boliviana (Salm-Dyck) R. Kiesling	D/I	A
Maihuenioideae	Maihuenia patagonica (Phil.) Britton & Rose	I/(D?)	A
Pereskioideae	Pereskia aculeata Mill.	I	M
	P. bahiensis Gürke	I	M
	P. grandifolia Haw.	I	M

I, indeterminate primary root growth; D, determinate primary root growth. A, arid; SA, semi-arid; M, mesic.