Yes. TD status follows the principal's TN and does not require the dependant to be a Canadian or Mexican citizen. The spouse may study in TD status but may not work, and would need a visa at a consulate if not visa-exempt.
Derivative status follows the principal; the work bar follows the spouse
The spouse and unmarried children under 21 of a TN professional may be admitted in TD status regardless of their own nationality, so a Canadian permanent resident spouse is eligible even though that spouse could never hold TN. Two practical differences follow from the spouse's passport. A Canadian citizen dependant is visa-exempt and can be admitted at the port of entry with the principal; a dependant of another nationality may need a TD visa issued by a U.S.
consulate first, which takes time and should be started early. Once admitted, TD permits full-time or part-time study but no employment of any kind, paid or unpaid, for a U.S. or foreign employer.
If the spouse intends to work, the family should look at the spouse's own qualifications and citizenship for an independent route, or at whether the agronomist's employer structure could support L-1, where L-2 spouses are employment-authorized incident to status.