No foreign equity is allowed in the practice of agriculture, although foreigners may practice the profession subject to reciprocity. Agriculture is, however, not listed among the activities under the Annex on Professions of the 11th Foreign Investment Negative List where foreigners may practice through the corporate form. In this case, the reciprocity requirement that is concurred in the case of of the practice of such profession may not apply to foreign corporate investments, cf. SEC-OGC Opinion No. 16-14, 23 May 2016, p. 3 ("[…] This means that the practice of profession by corporations should be done by 100% Filipino-owned corporations, as no foreign equity is allowed [...]). 
For the purposes of OECD FDI Regulatory Restrictiveness Index, the "no foreign equity" restriction has been recorded to all agricultural activities, except for corn and rice production which are explictly subject to less stringent restricitons.
"Only the investment areas and/or activities listed in the attached Eleventh Regular Foreign Investment Negative List shall be reserved for Philippine nationals, subject to the exceptions and conditions indicated therein.
[...]
LIST A: FOREIGN OWNERSHIP IS LIMITED BY MANDATE OF THE CONSTITUTION AND SPECIFIC LAWS
No Foreign Equity [...]
2. Practice of Professions² (Art. XII, Sec. 14 of the Constitution, Sec. 1 of R.A. No. 5181, Sec. 7[j] of R.A. No. 8981), including Radiologic and x-ray technology (R.A. No. 7431), Criminology (R.A. No. 6506), Law (Art. VIII, Section 5 of the Constitution; Rule 138, Sec. 2 of the Rules of Court of the Philippines), and Marine deck officers and marine engine officers (R.A. No. 10635), subject to the Annex on Professions attached herewith and forming an integral part of this document, indicating the professions where (a) foreigners are allowed to practice in the Philippines subject to reciprocity; and (b) where corporate practice is allowed. Foreigners may teach at higher education levels (R.A. No. 8292), provided the subject being taught is not a professional subject (i.e., included in a government board or bar examination). [²2 Section 1(b) of Professional Regulation Commission Resolution No. 2012-668 defines ‘practice of a profession” as an “activity/undertaking rendered by a registered and licensed professional or a holder of a Special Temporary Permit as defined in the scope of practice of a professional regulatory law.”]
[...]
ANNEX ON PROFESSIONS [Law is not present in the list of professions in items A and B of this Annex]
A. Foreigners are allowed to practice the following professions in the Philippines provided that their home country allows Filipinos to be admitted to the practice of these professions:
-Agriculture (Section 27, PRC Resolution No. 2000-663)[...]
[...]
B. Corporate practice is allowed in the following professions, subject to the requirements and conditions under the pertinent professional regulatory law:
-[agriculture is not present in the list of professions in item B of this Annex] [...]" (Eleventh Regular Foreign Investment Negative List (Executive Order No. 65 / 2018))
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"SECTION 14. The sustained development of a reservoir of national talents consisting of Filipino scientists, entrepreneurs, professionals, managers, high-level technical manpower and skilled workers and craftsmen in all fields shall be promoted by the State. The State shall encourage appropriate technology and regulate its transfer for the national benefit.
The practice of all professions in the Philippines shall be limited to Filipino citizens, save in cases prescribed by law.[...]" (Art XII, Sec 14 of the Constitution, Sec 1 of RA 5181, Sec 7.j of RA 8981)
Eleventh Regular Foreign Investment Negative List (Executive Order No. 65 / 2018)
[<a href="https://www.officialgazette.gov.ph/downloads/2018/10oct/20181029-EO-65-RRD.pdf">List</a>]