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                                                               EXHIBIT 4.7



                      EXCHANGE AND STOCK ISSUANCE AGREEMENT

                                 by and between

                          BIONOVA HOLDING CORPORATION,
                             a Delaware corporation

                                       and

                              SAVIA, S.A. de C.V.,
                              a Mexican corporation


                           Dated as of March 29, 2004
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                      EXCHANGE AND STOCK ISSUANCE AGREEMENT

      This EXCHANGE AND STOCK ISSUANCE AGREEMENT (this "Agreement") is dated as
of March 29, 2004, by and between BIONOVA HOLDING CORPORATION, a Delaware
corporation ("Bionova") and SAVIA, S.A. de C.V., a corporation (sociedad anonima
de capital variable) organized under the laws of the United Mexican States
("Savia").

      WHEREAS, Savia is presently the holder of the $55,459,743.57 principal
amount Promissory Note of Bionova, dated December 30, 2002 (the "Bionova Note").

      WHEREAS, Bionova has not made any payments of principal or interest on the
Bionova Note;

      WHEREAS, The Bionova Note became due and payable to Savia by its terms as
of December 31, 2003, at which time the aggregate principal amount and accrued
and unpaid interest under the Bionova Note totaled $79,799,547.57 (together with
accumulated interest from January 1, 2004 to the date on which the Debt
Forgiveness (defined below) is consummated, the "Savia Debt").

      WHEREAS, Savia and Bionova have entered into an Agreement in Principle,
dated February 2, 2004 (the "Agreement in Principle").

      WHEREAS, Pursuant to the Agreement in Principle, Savia desires to satisfy
$2,426,318.73 of the principal amount of the Bionova Note for 26,959,097 shares
of Bionova's common stock (the "Exchange") and to forgive $53,033,424.84 of the
principal amount, which is all of the principal balance of the Bionova Note that
will remain outstanding following the consummation of the Exchange, and all of
the accrued and unpaid interest under the Bionova Note (the "Debt Forgiveness")
subject to the terms and conditions set forth herein; and

      WHEREAS, Pursuant to the Agreement in Principle and following the
consummation of the Exchange and the Debt Forgiveness, Bionova desires to cancel
the Bionova Note.

      NOW, THEREFORE, in consideration of the mutual promises, representations,
warranties, covenants, conditions and agreements contained herein, and other
good and valuable consideration the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, intending to be legally bound by the terms
hereof, agree as follows:

      SECTION 1. DEFINITIONS.

      1.1 Definitions. As used in this Agreement, each capitalized term has the
meaning ascribed to it in this Section 1.1.

      "Ag-Biotech" means Ag-Biotech Capital, LLC, a Delaware limited liability
company and a wholly-owned Subsidiary of Savia.

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      "Agreement" has the meaning set forth in the preamble hereto.

      "Agreement in Principle" has the meaning set forth in the preamble hereto.

      "Bionova" has the meaning set forth in the preamble hereto.

      "Bionova Note" has the meaning set forth in the recitals hereto.

      "Board of Directors" means the board of directors of Bionova.

      "Closing" has the meaning set forth in Section 2.2.

      "Closing Date" shall mean the date on which the Closing occurs.

      "Commission" means the Securities and Exchange Commission.

      "Common Stock" means the common stock, $.01 par value per share, of
Bionova.

      "Confidential Information" has the meaning set forth in Section 10.7(a).

      "Convertible Preferred Stock" means the Series A Convertible Preferred
Stock, $.01 par value per share, of Bionova.

      "Debt" means, as to any Person, (i) all indebtedness of such Person for
borrowed money (whether by loan or the issuance and sale of debt securities) or
for the deferred purchase price of property or services (other than current
trade liabilities incurred in the ordinary course of business and payable in
accordance with customary practices), (ii) any other indebtedness of such Person
which is evidenced by a note, bond, debenture or similar instrument, (iii) all
obligations of such Person which are required by GAAP to be classified and
accounted for as capital leases on the balance sheet of such Person, (iv) all
obligations of such Person in respect of letters of credit, acceptances or
similar instruments issued or created for the account of such Person, (v) all
liabilities secured by any Lien on any property owned by such Person even though
such Person has not assumed or otherwise become liable for the payment thereof
and (vi) the net liability under all hedging obligations of such Person.

      "Debt Forgiveness" has the meaning set forth in the recitals hereto.

      "Exchange" has the meaning set forth in the recitals hereto.

      "Exchange Act" means the Securities Exchange Act of 1934.

      "Financial Statements" means audited consolidated financial statements of
Bionova and its Subsidiaries as filed with the Commission in accordance with the
reporting requirements of the Exchange Act, as amended for fiscal years ended
December 31, 2000, 2001 and 2002 and the unaudited interim periods reported
therein and through the date hereof.

      "Fiscal Year" means a twelve calendar month period ending on December 31
of any year.

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      "GAAP" means, with respect to Bionova and any Related Person domiciled in
the United States, those generally accepted accounting principles and practices
which are recognized as such by the Financial Accounting Standards Board (or any
generally recognized successor) in the United States on the Closing Date.

      "Governmental Person" means any national (Federal or foreign), state or
local government, any political subdivision or any governmental,
quasi-governmental, judicial, public or statutory instrumentality, authority,
agency, body or entity.

      "Indemnified Party" has the meaning set forth in Section 9.

      "Law" means any applicable statute, law, regulation, ordinance, rule,
treaty, judgment, order, decree, permit, concession, license or other
governmental restriction of the United States or any state or political
subdivision thereof or of any foreign country or any department, province or
other political subdivision thereof.

      "Lien" means, with respect to any property or assets, any right or
interest therein of a creditor to secure Debt owed to him or any other
arrangement with such creditor which provides for the payment of such Debt out
of such property or assets or which allows him to have such Debt satisfied out
of such property or assets prior to the general creditors of any owner thereof,
including any lien, mortgage, security interest, pledge, deposit, production
payment, rights of a vendor under any title retention or conditional sale
agreement or lease substantially equivalent thereto, tax lien, mechanic's or
materialman's lien, or any other charge or encumbrance for security purposes,
whether arising by law or agreement or otherwise, but excluding any right of
offset which arises without agreement in the ordinary course of business. "Lien"
also means any filed financing statement, any registration of a pledge (such as
with an issuer of unregistered securities), or any other arrangement or action
which would serve to perfect a Lien described in the preceding sentence,
regardless of whether such financing statement is filed, such registration is
made, or such arrangement or action is undertaken before or after such Lien
exists.

      "Material Adverse Effect" means, as to any Person, a material adverse
effect on:

      (i)   the Property, business, operations, financial condition, liabilities
            or capitalization of such Person taken as a whole; or

      (ii)  the ability of such Person to timely perform its obligations under
            any of the Transaction Documents to which it is a party; or

      (iii) the validity or enforceability of any of the Transaction Documents;
            or

      (iv)  the rights, remedies, powers and privileges of such Person under any
            of the Transaction Documents.

      "Merger" means the Delaware short-form merger of Ag-Biotech Capital Inc.
with and into Bionova, with Bionova as the surviving corporation, in accordance
with the terms set forth in the Certificate of Ownership and Merger to be filed
with the Secretary of State of the State of Delaware.


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      "Order" means any order, writ, injunction, decree, judgment, award,
determination, direction or demand of any Governmental Person, court or
arbitrator with competent jurisdiction..

      "Person" means an individual, corporation, partnership, limited liability
company, association, joint stock company, trust or trustee thereof, estate or
executor thereof, unincorporated organization or joint venture, court or
governmental unit or any agency or subdivision thereof, or any other legally
recognizable entity.

      "Property" means any interest in any kind of property or asset, whether
real, personal or mixed.

      "Related Person" means any of Bionova or its Subsidiaries, whether now
existing or hereafter formed or acquired.

      "Restricted Securities" has the meaning set forth under Rule 144
promulgated under the Securities Act.

      "Savia" has the meaning set forth in the preamble hereto.

      "Savia Debt" has the meaning set forth in the recitals hereto.

      "Securities Act" means the Securities Act of 1933, as amended, or any
similar federal statute, and the rules and regulations promulgated thereunder,
all as the same shall be in effect at the time.

      "Series A Convertible Preferred Stock" means the 200 shares of Convertible
Preferred Stock currently held by Ag-Biotech, which may be converted into
23,156,116 shares of Common Stock if Bionova adopts and files an amendment to
its corporate charter increasing the authorized number of shares of Common Stock
to at least 70,000,000.

      "Subsidiary" means, with respect to any Person, any corporation,
partnership or other entity of which at least a majority of the securities or
other ownership interests having by the terms thereof ordinary voting power to
elect a majority of the board of directors or other persons performing similar
functions of such corporation, partnership or other entity (irrespective of
whether or not at the time securities or other ownership interests of any other
class or classes of such corporation, partnership or other entity have or might
have voting power by reason of the happening of any contingency) which is at the
time directly or indirectly owned or controlled by such Person or one or more
Subsidiaries of such Person or by such Person and one or more Subsidiaries of
such Person.

      "Transaction Documents" means (i) this Agreement and any other agreement
entered into in connection with, as a condition of, or pursuant to this
Agreement, by and between Bionova or any Subsidiary thereof, on the one hand,
and Savia or any Affiliate thereof, on the other hand, including, without
limitation, the Agreement in Principle, and (ii) the Certificate of Ownership
and Merger to be filed with the Secretary of State of the State of Delaware in
connection with the Merger.

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      1.2 Accounting Terms and Determinations. Except as otherwise expressly
provided for in this Agreement, all accounting terms used in this Agreement
shall be interpreted, all determinations with respect to accounting matters
hereunder shall be made, and all financial statements and certificates and
reports as to financial matters required to be delivered to Savia under this
Agreement shall be prepared in accordance with GAAP, applied on a basis
consistent with those used in the preparation of the latest financial statements
furnished to Savia under this Agreement. To enable the ready and consistent
determination of compliance with the covenants set forth herein, Bionova will
not change the last day of its fiscal year from December 31 of each year.

      1.3 Interpretation. In this Agreement, unless otherwise indicated, the
singular includes the plural and conversely; words importing one gender include
the others; references to statutes or regulations are to be construed as
including all statutory or regulatory provisions consolidating, amending or
replacing the statute or regulation referred to; references to "writing" include
printing, typing, lithography and other means of reproducing words in a tangible
visible form; the word "or" shall not be exclusive (i.e., shall be deemed to
include "and/or"); the words "including," "includes" and "include" shall be
deemed to be followed by the words "without limitation"; references to articles,
sections (or subdivisions of sections), exhibits, annexes or schedules without
reference to a specific other document are to such parts of this Agreement;
references to agreements and other contractual instruments shall be deemed to
include all subsequent amendments, extensions and other modifications to such
instruments (without, however, limiting any prohibition on any such amendments,
extensions and other modifications by the terms of this Agreement); and
references to Persons include their respective permitted successors and assigns
and, in the case of Governmental Persons, Persons succeeding to their respective
functions and capacities.

      SECTION 2. EXCHANGE OF SECURITIES AND DEBT FORGIVENESS.

      2.1 Exchange. Savia agrees to credit $2,426,318.73 of the $55,459,743.57
principal amount of the Bionova Note for 26,959,097 shares of Common Stock,
subject to the terms and conditions set forth herein.

      2.2 Debt Forgiveness. Immediately prior to the effectiveness of the
Merger, Savia agrees to forgive $53,033,424.84 of the principal amount of the
Bionova Note, which is all of the principal balance of the Bionova Note that
will remain outstanding following the consummation of the Exchange, and all
accrued and unpaid interest thereon.

      2.3 Bionova agrees and Savia acknowledges that upon consummation of the
Exchange and the Debt Forgiveness, the Bionova Note shall be cancelled.

      2.4 The Closing. The Closing will take place at the offices of Milbank,
Tweed, Hadley & McCloy LLP, 1 Chase Manhattan Plaza, New York, New York 10005,
or at such other place as the parties hereto mutually agree, at 10:00 a.m. local
time, on the Closing Date. At the closing of the Exchange and the Debt
Forgiveness (the "Closing"): (i) Savia shall deliver to Bionova the Bionova
Note; (ii) Bionova shall accept the Bionova Note; and (iii) Bionova shall cancel
the Bionova Note.

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      2.5 Further Assurances.

      (a) At any time and from time to time after the Closing, Bionova (at its
own expense) shall execute and deliver to Savia such other documents and
instruments, provide such materials and information and take such other actions
as Savia may reasonably request to more effectively vest title to the 26,959,097
shares of Common Stock.

      (b) Following the Closing, Bionova will afford Savia, its counsel and its
accountants, during normal business hours, reasonable access to the books,
records and other data relating to the business or condition of Bionova and the
right to make copies and extracts therefrom.

      SECTION 3. REPRESENTATIONS AND WARRANTIES OF BIONOVA.

      Bionova hereby represents and warrants to Savia, as of the date hereof and
as of the Closing Date, that each of the representations and warranties set
forth below is true and correct in all material respects. 3.1 Organization and
Authorization.


      (a) Bionova (i) is a corporation duly organized, validly existing and in
good standing under the laws of its jurisdiction of incorporation or formation,
and (ii) has all requisite power and authority to own or hold under lease the
property it purports to own or hold under lease and to transact the business in
which it is presently engaged or presently proposes to engage.

      (b) Bionova has all requisite power and authority to execute and deliver
this Agreement and any other documents or agreements contemplated hereby and to
which it is a party, to perform its obligations hereunder and thereunder and to
consummate the transactions contemplated hereunder and thereunder. Bionova has
all requisite power and authority to issue the 26,959,097 shares of Common Stock
in connection with the Exchange. The execution and delivery of this Agreement
and the issuance of the 26,959,097 shares of Common Stock in connection with the
Exchange, the performance of this Agreement, and the execution, delivery and
performance of any other documents or agreements to which Bionova is a party
contemplated hereby and thereby, and the consummation of the transactions
contemplated hereby and thereby, have been duly authorized and approved by
Bionova's Board of Directors. Each of this Agreement and any other document or
agreement contemplated hereby to which Bionova is a party has been (or on the
Closing Date will have been) duly authorized, executed and delivered by, and
each is (or, when duly executed and delivered on the Closing Date, will be) the
valid and binding obligation of Bionova, enforceable in accordance with its
terms, except as may be limited by applicable bankruptcy, reorganization,
insolvency, moratorium or other similar laws or by legal or equitable principles
relating to or limiting creditors' rights generally.

      (c) Schedule 3.1 contains a true and correct list of all Subsidiaries of
Bionova. Except as set forth on Schedule 3.1, Bionova has good and valid title
to all the outstanding stock of each of its Subsidiaries, in each case, free and
clear of all Liens.

      3.2 Capital Stock.

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      (a) The total number of shares of capital stock which Bionova currently
has authority to issue under its Articles of Incorporation is (i) 50,000,000
shares of Common Stock, of which 23,012,753 are issued and outstanding, all of
which outstanding shares are duly and validly issued and fully paid and
non-assessable, and (ii) 5,000 shares of Convertible Preferred Stock, of which
200 are issued and outstanding.

      (b) As of the date hereof and after giving effect to the transactions
contemplated by the Transaction Documents and except for the Bionova Note and
the Series A Convertible Preferred Stock, Bionova does not, and as of the
Closing Date, Bionova will not, have outstanding any capital stock or other
securities convertible into or exchangeable for any of its capital stock or any
rights to subscribe for or to purchase, or any options for the purchase of, or
any agreements (contingent or otherwise) providing for the issuance of, or any
calls, commitments or claims of any character relating to, any of its capital
stock or any securities convertible into or exchangeable for any of its capital
stock, other than as set forth on Schedule 3.2 (which schedule shall include the
exercise price and number of shares).

      (c) As of the date hereof, except as provided in this Agreement, Bionova
does not have any obligation (contingent or otherwise) to repurchase or
otherwise acquire or retire any of its capital stock or obligation evidencing
the right of the holder thereof to purchase any of its capital stock. Other than
this Agreement, there is not in effect on the date hereof any agreement by
Bionova or any of its Subsidiaries pursuant to which any holders of securities
of Bionova or any of its Subsidiaries (other than Savia and its Affiliates) have
a right to cause Bionova to register such securities under the Securities Act.

      (d) As of the Closing and immediately thereafter, the authorized capital
stock of Bionova will consist solely of (i) 50,000,000 shares of Common Stock,
all of which shares will be issued and outstanding, and (ii) 5,000 shares of
Convertible Preferred Stock, of which 200 shares will be issued and outstanding.
As of the Closing and immediately thereafter, all of the outstanding shares of
Bionova's capital stock shall be duly authorized, validly issued, fully paid and
non-assessable.

      3.3 Private Offering. During the six months prior to the Closing Date,
neither Bionova nor any other Person acting on behalf of Bionova has offered any
securities of Bionova (excluding options or warrants to employees and shares
issuable upon exercise or conversion of securities outstanding prior to the date
hereof) for sale to, or solicited offers to buy any thereof from, or otherwise
approached or negotiated with respect thereto with, any Person other than
prospective holders of such securities who are "accredited investors", as
defined in Rule 501 of Regulation D promulgated under the Securities Act.
Bionova agrees that neither Bionova nor anyone acting on its behalf has offered
or will offer securities for issue or sale to, or has solicited or will solicit
any offer to acquire any of the same from, anyone so as to bring the issuance
and sale of the 26,959,097 shares of Common Stock under Section 5 of the
Securities Act. Based in part on the representations of Savia set forth herein,
the offer, sale and issuance of the 26,959,097 shares of Common Stock in
conformity with the terms of this Agreement are exempt from the registration
requirements of the Securities Act and any applicable state securities laws.

      3.4 No Broker's or Other Fees. Other than with respect to the fairness
opinion required pursuant to Section 5.7 hereof, no broker, finder or investment
banker is entitled to any

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fee or commission in connection with the transactions contemplated hereby based
upon arrangements made by or on behalf of Bionova.

      SECTION 4. REPRESENTATIONS AND WARRANTIES OF SAVIA.

      Savia hereby represents and warrants to Bionova, as of the date hereof and
as of the Closing Date, that each of the representations and warranties set
forth below is true and correct in all material respects: 4.1 Authority.

      (a) Savia represents and warrants that it is a corporation duly organized,
validly existing and in good standing under the laws of the United Mexican
States.

      (b) Savia has all requisite power and authority to execute and deliver
this Agreement and any other documents or agreements contemplated hereby and to
which it is a party, to perform its obligations hereunder and thereunder and to
consummate the transactions contemplated hereunder and thereunder. Savia
represents and warrants that the execution and delivery by it of this Agreement,
and the performance of its obligations hereunder, has been duly and validly
authorized by the all necessary action of Savia. This Agreement has been duly
and validly executed and delivered by Savia and constitutes the legal, valid and
binding obligations of Savia, enforceable against Savia, in accordance with its
terms, except to the extent such enforceability (i) may be limited by
bankruptcy, insolvency, reorganization, moratorium or other similar laws
relating to creditors' rights generally and (ii) is subject to general
principles of equity.

      4.2 Acquisition for Savia's Account. Savia represents and warrants that it
is acquiring and will acquire the 26,959,097 shares of Common Stock for its own
account, with no present intention of distributing or reselling such securities,
or any part thereof, in violation of applicable securities laws.

      4.3 Investment Experience. Savia has such knowledge and experience in
financial and business matters, including investing in securities of new and
speculative companies, as to be able to evaluate the merits and risks of an
investment in the 26,959,097 shares of Common Stock.

      4.4 Securities Not Registered. Savia acknowledges that the 26,959,097
shares of Common Stock have not been registered under the Securities Act or the
securities laws of any state in the United States or any other jurisdiction and
may not be offered or sold by Savia unless subsequently registered under the
Securities Act (if applicable to the transaction) and any other securities laws
or unless exemptions from the registration or other requirements thereof are
available for the transaction.

      4.5 Accredited Investor. Savia represents that it is an "accredited
investor" within the meaning of Rule 501 of Regulation D promulgated under the
Securities Act, as presently in effect.

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      4.6 Acknowledgement of Risk. Savia acknowledges that an investment in the
26,959,097 shares of Common Stock involves a high degree of risk and represents
that it understands the economic risk of such investment. Savia is prepared to
bear the economic risk of retaining the 26,959,097 shares of Common Stock for an
indefinite period, without prejudice, however, to the rights of Savia, in
accordance with this Agreement, lawfully to sell or otherwise dispose of all or
any part of the 26,959,097 shares of Common Stock held by it.

      4.7 No Public Solicitation. To the best of Savia's knowledge, the issuing
of the 26,959,097 shares of Common Stock to Savia was made through direct,
personal communication between Savia and a representative of Bionova and not
through public solicitation and advertising.


      SECTION 5. CONDITIONS PRECEDENT TO OBLIGATIONS OF SAVIA.


      The obligations of Savia are subject to the fulfillment, at or before the
Closing, of each of the following conditions (all or any of which may be waived
in whole or in part by Savia in its sole discretion):

      5.1 Representations and Warranties. Each of the representations and
warranties made by Bionova in this Agreement (other than those made as of a
specified date earlier than the Closing Date) shall be true and correct in all
material respects on and as of the Closing Date as though such representation or
warranty was made on and as of the Closing Date, and any representation or
warranty made as of a specified date earlier than the Closing Date shall have
been true and correct in all material respects on and as of such earlier date.

      5.2 Performance. Bionova shall have performed and complied with, in all
material respects, each agreement, covenant and obligation required by this
Agreement to be so performed or complied with by Bionova at or before the
Closing.

      5.3 Orders and Laws.

      (a) The parties hereto shall have complied in full with the requirements
of the Exchange Act in connection with the execution and delivery of this
Agreement or any of the other Transaction Documents and the performance and
consummation of any of the transactions contemplated by this Agreement or any of
the other Transaction Documents, including, without limitation, the passing of
twenty (20) days from the date of the mailing of a Rule 13e-3 Transaction
Statement on Schedule 13E-3 to the stockholders of Bionova not affiliated with
Savia and its Affiliates.

                  (b) There shall not be in effect on the Closing Date any Order
or Law restraining, enjoining or otherwise prohibiting or making illegal the
execution of this Agreement or the consummation of any of the transactions
contemplated by this Agreement or any of the other Transaction Documents or
which could reasonably be expected to otherwise result in a material diminution
of the benefits of the transactions contemplated by this Agreement or any of the
other Transaction Documents to Savia, and there shall not be pending or
threatened on the Closing Date any action, claim, lawsuit or proceeding in,
before or by any Governmental Person or regulatory authority seeking the
imposition of monetary damages, injunctive or other

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equitable relief against Savia, which could reasonably be expected to result in
the issuance of any such Order or the enactment, promulgation or deemed
applicability of any such Law to Savia, Bionova, any Subsidiary thereof or the
transactions contemplated by this Agreement or any of the other Transaction
Documents of any such Law.

      5.4 Regulatory Consents and Approvals. All consents, approvals and actions
of, filings with and notices to any Governmental Person or regulatory authority
necessary to permit Savia and Bionova to perform their obligations under this
Agreement and the other Transaction Documents and to consummate the transactions
contemplated hereby and thereby (i) shall have been duly obtained, made or
given, (ii) shall be in form and substance reasonably satisfactory to Savia,
(iii) shall not be subject to the satisfaction of any condition that has not
been satisfied or waived and (iv) shall be in full force and effect, and all
terminations or expirations of waiting periods imposed by any Governmental
Person or regulatory authority necessary for the consummation of the
transactions contemplated by this Agreement and the other Transaction Documents,
shall have occurred.

      5.6 Fairness Opinion. Prior to the filing required under Section 5.9 and
Section 6.3, Bionova shall have received from AgriCapital Securities Inc. a
fairness opinion, in form and substance acceptable to Savia, with respect to the
fairness of the Exchange and the Merger per share "cash-out" price to be paid to
stockholders of Bionova not affiliated with Savia or its Affiliates, from a
financial point of view, which opinion is not withdrawn prior to the
consummation of the transactions contemplated by this Agreement and the other
Transaction Documents.

      5.7 Transaction Documents. All Transaction Documents shall be in form and
substance reasonably satisfactory to Savia and its counsel.

      5.8 Fees and Expenses. Neither Bionova nor Savia (or any Subsidiary of
Savia) incurs significant expenses associated with the Exchange, the Debt
Forgiveness or the Merger, other than approximately $650,000 of professional
fees and other expenses that Bionova contemplates will be incurred by Bionova,
Savia and Ag-Biotech in connection with (i) the preparation and dissemination of
a Rule 13e-3 Transaction Statement on Schedule 13E-3 to the stockholders of
Bionova not affiliated with Savia and its affiliates and (ii) the consummation
of the Exchange, the Debt Forgiveness and the Merger in an efficient and prompt
manner.

      5.9 Filing and Dissemination of Information. Bionova, Savia and Ag-Biotech
shall have jointly (i) filed with the Commission a Schedule 13E-3 pursuant to
Rule 13e-3 promulgated under the Exchange Act, and (ii) disseminated to the
holders of Common Stock the Rule 13e-3 Transaction Statement on Schedule 13E-3
required under Rule 13e-3(e) of the Exchange Act, all of which shall be in full
compliance with the requirements therefor established by the Commission. The
expiration of any waiting period imposed by the Commission necessary for the
consummation of the transactions contemplated by the Exchange, the Debt
Forgiveness and the Merger shall have occurred.

      5.10 Material Adverse Change. There shall not have occurred any event
that, in Savia's good faith judgment, resulted in an actual or threatened
material adverse change in the business or condition of Bionova since the date
of the Agreement in Principle.

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      SECTION 6. CONDITIONS PRECEDENT TO OBLIGATIONS OF BIONOVA.


      The obligations of Bionova hereunder are subject to the fulfillment, at or
before the Closing, of each of the following conditions (all or any of which may
be waived in whole or in part by Bionova in its sole discretion):

      6.1 Representations and Warranties. Each of the representations and
warranties made by Savia in this Agreement shall be true and correct in all
material respects on and as of the Closing Date as though such representation or
warranty was made on and as of the Closing Date.

      6.2 Performance. Savia shall have performed and complied with, in all
material respects, each agreement, covenant and obligation required by this
Agreement to be so performed or complied with by Savia at or before the Closing.

      6.3 Filing and Dissemination of Information. Bionova, Savia and Ag-Biotech
shall have jointly (i) filed with the Commission a Schedule 13E-3 pursuant to
Rule 13e-3 promulgated under the Exchange Act, and (ii) disseminated to the
holders of Common Stock the Rule 13e-3 Transaction Statement on Schedule 13E-3
required under Rule 13e-3(e) of the Exchange Act, all of which shall be in full
compliance with the requirements therefor established by the Commission. The
expiration of any waiting period imposed by the Commission necessary for the
consummation of the transactions contemplated by the Exchange, the Debt
Forgiveness and the Merger shall have occurred.

      6.4 Fairness Opinion. Prior to the filing required under Section 5.10 and
Section 6.3, Bionova shall have received from AgriCapital Securities Inc. a
fairness opinion, in form and substance acceptable to Savia, with respect to the
fairness of the Exchange and the Merger per share "cash-out" price to be paid to
the stockholders of Bionova not affiliated with Savia or its Affiliates, from a
financial point of view, which opinion is not withdrawn prior to the
consummation of the transactions contemplated by this Agreement or the other
Transaction Documents.

      6.5 Orders and Laws. There shall not be in effect on the Closing Date any
Order of Law restraining, enjoining or otherwise prohibiting or making illegal
the consummation of any of the transactions contemplated by this Agreement or
any of the other Transaction Documents or which could reasonably be expected to
otherwise result in a material diminution of the benefits of the transactions
contemplated by this Agreement or any of the other Transaction Documents to
Bionova, and there shall not be pending or threatened on the Closing Date any
action, claim, lawsuit or proceeding in, before or by any Governmental Person or
regulatory authority which could reasonably be expected to result in the
issuance of any such Order or the enactment, promulgation or deemed
applicability to Savia, Bionova, any of Bionova's Subsidiaries or the
transactions contemplated by this Agreement or any of the other Transaction
Documents of any such Law.

      6.6 Transaction Documents. All Transaction Documents shall be in form and
substance reasonably acceptable to Bionova and its counsel.

                                       11
<PAGE>
      SECTION 7. COVENANTS.

      7.1 Fulfillment of Conditions. Each party hereto will execute and deliver
at the Closing each Transaction Document that it is required hereby to execute
and deliver as a condition to the Closing, will take all commercially reasonable
steps necessary or desirable and proceed diligently and in good faith to satisfy
each other condition to the obligations of the parties hereto contained in this
Agreement and will not, and will not permit any of its Affiliates to, take or
fail to take any action that could reasonably be expected to result in the
nonfulfillment of any such condition.

      7.2 Restricted Cash Account. Bionova and Savia agree that Bionova will
deposit $300,000.00 into a restricted cash account for a period not to exceed
one (1) year from the date hereof, which funds will be used exclusively to
satisfy any third-party claims against any of the individuals who are covered by
the directors' and officers' liability insurance policy provided for directors
and officers of Bionova and its Subsidiaries as of the date hereof and any
litigation expenses directly related to such claims; provided that such funds
shall not be released from such account and so disbursed to the extent that any
such individual receives the benefit of any proceeds under such directors' and
officers' liability policy to discharge any portion of such claim.

      SECTION 8. TRANSFERABILITY.

      8.1 Restrictive Legend. Each certificate evidencing the 26,959,097 shares
of Common Stock issued by Bionova shall be stamped or otherwise imprinted with a
legend in substantially the following form:

      "THE SECURITIES EVIDENCED BY THIS STOCK CERTIFICATE HAVE NOT BEEN
      REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE
      SECURITIES LAWS. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
      HEREIN MAY BE OFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR
      OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH
      TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION."

provided, that such restrictive legend shall not be required after the date on
which the securities evidenced by a certificate bearing such a restrictive
legend no longer constitute Restricted Securities, and upon the request of the
holder of such certificate, Bionova, without expense to Savia, shall issue a new
certificate not bearing the restrictive legend otherwise required to be borne
thereby.

      8.2 Transferability. Savia agrees not to make any disposition of all or
any portion of the 26,959,097 shares of Common Stock unless and until the
transferee has agreed in writing for the benefit of Bionova to be bound by this
Agreement provided and to the extent it is then applicable, unless there is then
in effect a registration statement under the Securities Act


                                       12
<PAGE>
covering such proposed disposition and such disposition is made in accordance
with such registration statement, and if reasonably requested by Bionova, Savia
shall have furnished Bionova with an opinion of counsel, reasonably satisfactory
to Bionova, that such disposition will not require registration of such shares
under the Securities Act. It is agreed that Bionova will not require opinions of
counsel for transactions made pursuant to Rule 144.

      SECTION 9. MISCELLANEOUS.

      9.1 Waivers and Amendments; Acknowledgment. No failure or delay (whether
by course of conduct or otherwise) by Bionova or Savia in exercising any right,
power or remedy which either may have under any of the Transaction Documents
shall operate as a waiver thereof or of any other right, power or remedy, nor
shall any single or partial exercise by Bionova or Savia of any such right,
power or remedy preclude any other or further exercise thereof or of any other
right, power or remedy. No waiver of any provision of any Transaction Document
and no consent to any departure therefrom shall ever be effective unless it is
in writing and signed by the parties hereto, and then such waiver or consent
shall be effective only in the specific instances and for the purposes for which
given and to the extent specified in such writing. This Agreement and the other
Transaction Documents set forth the entire understanding and agreement of the
parties hereto and thereto with respect to the transactions contemplated herein
and therein and supersede all prior discussions and understandings with respect
to the subject matter hereof and thereof, and no modification or amendment of or
supplement to this Agreement shall be valid or effective unless the same is in
writing and signed by the party against whom it is sought to be enforced. THIS
WRITTEN AGREEMENT AND THE OTHER TRANSACTION DOCUMENTS REPRESENT THE FINAL
AGREEMENT BETWEEN THE PARTIES HERETO AND MAY NOT BE CONTRADICTED BY EVIDENCE OF
PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES HERETO.
This Agreement may be amended, but only with the written consent of each of the
parties hereto. The remedies provided for herein are cumulative and are not
exclusive of any remedies that may be available to Savia or Bionova at law or in
equity or otherwise.

      9.2 Survival of Agreements; Cumulative Nature. The various representations
and warranties in this Agreement shall not survive the Closing or the issuance
to Savia of the 26,959,097 shares of Common Stock and the delivery of the
26,959,097 shares of Common Stock to Savia and the other Transaction Documents.
All covenants and agreements in this Agreement shall survive the Closing or the
issuance to Savia of the 26,959,097 shares of Common Stock and the delivery of
the 26,959,097 shares of Common Stock to Savia and the other Transaction
Documents.

      9.3 Notices. All notices, requests, consents, demands and other
communications required or permitted hereunder shall be in writing, unless
otherwise specifically provided, and shall be deemed sufficiently given or
furnished upon delivery, when delivered by personal delivery, by telecopy, by
delivery service with proof of delivery, or three days after being deposited in
the United States mail as registered or certified United States mail, postage
prepaid, to Bionova or Savia at the addresses set forth on the signature pages
hereto (unless changed by similar notice in writing given by the particular
Person whose address is to be changed).

                                       13
<PAGE>
      9.4 Governing Law; Submission to Process. EXCEPT TO THE EXTENT THAT THE
LAW OF ANOTHER JURISDICTION IS EXPRESSLY ELECTED IN A TRANSACTION DOCUMENT, THIS
AGREEMENT AND THE OTHER TRANSACTION DOCUMENTS, SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT
REGARD TO PRINCIPLES OF CONFLICTS OF LAW. EACH OF BIONOVA AND SAVIA HEREBY
IRREVOCABLY SUBMITS ITSELF AND EACH OTHER RELATED PERSON TO THE NON-EXCLUSIVE
JURISDICTION OF THE STATE AND FEDERAL COURTS SITTING IN THE STATE OF NEW YORK
AND THE COUNTY OF NEW YORK AND AGREES AND CONSENTS THAT SERVICE OF PROCESS MAY
BE MADE UPON IT OR ANY OF ITS SUBSIDIARIES IN ANY LEGAL PROCEEDING RELATING TO
THE TRANSACTION DOCUMENTS BY ANY MEANS ALLOWED UNDER NEW YORK OR FEDERAL LAW.
EACH OF BIONOVA AND SAVIA IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY
APPLICABLE LAW, ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO THE LAYING OF
THE VENUE OF ANY SUCH PROCEEDING BROUGHT IN SUCH A COURT AND ANY CLAIM THAT ANY
SUCH PROCEEDING BROUGHT IN SUCH A COURT HAS BEEN BROUGHT IN AN INCONVENIENT
FORUM.

      9.5 Waiver of Jury Trial, Punitive Damages, Etc. EACH OF BIONOVA AND SAVIA
HEREBY:

      (a) KNOWINGLY, VOLUNTARILY, INTENTIONALLY, AND IRREVOCABLY WAIVES, TO THE
MAXIMUM EXTENT NOT PROHIBITED BY LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY
IN RESPECT OF ANY LITIGATION BASED HEREON, OR DIRECTLY OR INDIRECTLY AT ANY TIME
ARISING OUT OF, UNDER OR IN CONNECTION WITH THE TRANSACTION DOCUMENTS OR THE
PURCHASE AND SALE OF ANY NEW COMMON STOCK CONTEMPLATED THEREBY OR ASSOCIATED
THEREWITH;

      (b) IRREVOCABLY WAIVES, TO THE MAXIMUM EXTENT NOT PROHIBITED BY LAW, ANY
RIGHT IT MAY HAVE TO CLAIM OR RECOVER IN ANY SUCH LITIGATION ANY SPECIAL,
EXEMPLARY, PUNITIVE OR CONSEQUENTIAL DAMAGES, OR DAMAGES OTHER THAN, OR IN
ADDITION TO, ACTUAL DAMAGES;

      (c) CERTIFIES THAT NO PARTY HERETO NOR ANY REPRESENTATIVE OR AGENT OR
COUNSEL FOR ANY PARTY HERETO HAS REPRESENTED, EXPRESSLY OR OTHERWISE, OR IMPLIED
THAT SUCH PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE
FOREGOING WAIVERS; AND

      (d) ACKNOWLEDGES THAT IT HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT,
THE OTHER TRANSACTION DOCUMENTS AND THE TRANSACTIONS CONTEMPLATED HEREBY AND
THEREBY BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS CONTAINED
IN THIS SECTION.

                                       14
<PAGE>
      9.6 Exhibits and Schedules; Additional Definitions. All Exhibits and
Schedules to this Agreement are a part hereof for all purposes.

      9.7 Successors and Assigns. Except as otherwise expressly provided herein,
this Agreement shall inure to the benefit of and be binding upon the successors
and permitted assigns of each of the parties hereto whether so expressed or not.

      9.8 Counterparts. Two or more duplicate originals of this Agreement may be
signed by the parties hereto, each of which shall be an original but all of
which together shall constitute one and the same instrument.

      9.9 Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable, the validity, legality and enforceability of
any such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

      9.10 Specific Performance. Bionova recognizes that money damages may be
inadequate to compensate Savia for a breach by Bionova of its obligations
hereunder, and Bionova irrevocably agrees that Savia shall be entitled to the
remedy of specific performance or the granting of such other equitable remedies
as may be awarded by a court of competent jurisdiction in order to afford Savia
the benefits of this Agreement and that Bionova shall not object and hereby
waives any right to object to such remedy or such granting of other equitable
remedies on the grounds that money damages will be sufficient to compensate
Savia.


                                       15
<PAGE>
      IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Agreement as of the date first above written.

                  BIONOVA HOLDING CORPORATION,
                  a Delaware corporation


                  By:      /s/ Jose Manuel Garcia
                            ----------------------
                           Jose Manuel Garcia
                           Chief Executive Officer

                  P.O. Box 1586
                  Nogales, Arizona 85628-1586
                  Attention: Jose Manuel Garcia
                  Telephone:  (609) 744-8105


                  With a copy to:
                  Thompson & Knight LLP
                  1700 Pacific Avenue, Suite 3300
                  Dallas, Texas 75201
                  Attention: Michael C. Titens, Esq.


                  SAVIA, S.A., DE C.V.,
                  a United Mexican States corporation

                  By:      /s/ Alfonso Romo
                            ----------------
                           Alfonso Romo
                           Chief Executive Officer

                  Address for Notices:

                  Rio Sena 500 Pte.
                  Colonia del Valle
                  San Pedro Garza Garcia, N.L.
                  CP 66220 Mexico
                  Attention: Alfonso Romo
                  Telephone: (52-81) 8173-5500


                  With a copy to:
                  Milbank, Tweed, Hadley & McCloy LLP
                  1 Chase Manhattan Plaza
                  New York, New York 10005
                  Attention: Howard S. Kelberg, Esq.
                  Telephone:  (212) 659-4469
                  Facsimile:   (212) 659-4819