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                                                                 Exhibit 10.62.1

                                    AMENDMENT

     THIS AMENDMENT is made as of the 15th day of June, 2000, between General
Electric Capital Corporation ("Secured Party") and Deltagen, Inc. ("Debtor") in
connection with that certain Master Security Agreement dated or dated as of
June 15, 2000 ("Agreement"). The terms of this Amendment are hereby
incorporated into the Agreement as though fully set forth therein. Section
references below refer to the section numbers of the Agreement. The Agreement is
hereby amended as follows:

     2. REPRESENTATIONS, WARRANTIES AND COVENANTS OF DEBTOR.

     In Subsection (c) the following is added at the end thereof after the word
     "laws" and before the semicolon: or other similar laws of general
     application relating to or affecting the enforcement of creditors' rights
     generally or by principles of equity pertaining to the availability of
     equitable remedies."

     In Subsection (e)(i), Line 2, the following is hereby added after the words
     "applicable to Debtor" and before the comma: "except any violation which
     would not have a material adverse effect upon the enforceability of the
     Debt Documents or Debtor's ability to perform its obligations under the
     Debt Documents."

     In Subsection (e)(ii), Line 2, the following is hereby added after the
     words "Debtor is a party" and before the comma: "except any breach or
     default which would not have a material adverse effect upon the
     enforceability of the Debt Documents or Debtor's ability to perform its
     obligations under the Debt Documents."

     Subsection (f) is hereby amended and replaced in its entirety as follows:

          (f) Except as disclosed to Secured Party in the S-I Amendment filed by
          Debtor with the Securities and Exchange Commission on June 15, 2000,
          there are no suits or proceedings pending in court or before any
          commission, board or other administrative agency against or affecting
          Debtor which could, in the aggregate, have a material adverse effect
          on Debtor, its business or operations, or its ability to perform its
          obligations under the Debt Documents, nor to Debtor's knowledge, are
          any such suits or proceedings are threatened;

     Subsection (j) is hereby amended by adding the following after the words
     "in possession of" in the first line: "(except as permitted in Section 3(c)
     hereof)."

     Subsection (k) is hereby amended by adding the word "reasonable" before the
     word "judgment" in the second line.

     3. COLLATERAL.

     Subsection (c) is hereby amended and replaced with the following:

          "(c) Debtor shall not, without the prior written consent of Secured
     Party, (i) part with possession of any of the Collateral (except to Secured
     Party or for maintenance and repair), (ii) remove any of the Collateral
     from the address specified in the Collateral Schedule, or (iii) sell, rent,
     lease, mortgage, grant a security interest in or otherwise transfer or
     encumber (except for Permitted Liens) any of the Collateral."

     In the first line of Subsection (d), the words "when due" are replaced
     with the words "prior to delinquency."

     In the second line of Subsection (d), the following words are inserted
     after the word "option" and before the comma: "after the occurrence and
     continuation of a default."

     In the fourth line of subsection (d), the word "written" is hereby added
     before the word "demand" and the word "reasonable" is hereby added before
     the word "costs."

     4. INSURANCE.

     In the fourth line of subsection (b), the word "reasonably" is hereby added
     before the word "acceptable."

     In the ninth line of subsection (b), the words "after consultation with
     Debtor" are hereby added after the words "Secured Party" and the word
     "Debtors" is hereby changed to "Debtor's."

     5.REPORTS

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     Section 5 is hereby amended and replaced with the following:

          5.   REPORTS.

               (a) Debtor shall promptly notify Secured Party of (i) any change
          in the name of Debtor, (ii) any relocation of its chief executive
          offices, (iii) any relocation of any of the Collateral, which
          relocation may not be made unless Debtor has obtained the prior
          written consent of Secured Party which shall not be unreasonably
          withheld, (iv) any of the Collateral being lost, stolen, missing,
          destroyed, materially damaged or worn out, or (v) any lien, claim or
          encumbrance other than Permitted Liens attaching to or being made
          against any of the Collateral.

               (b) Debtor will deliver to Secured Party financial statements as
          follows. If Debtor is a privately held company, then Debtor agrees to
          provide monthly financial statements, certified by Debtor's chief
          financial officer including a balance sheet, statement of operations
          and cash flow statement within 30 days of each month end, and its
          complete audited annual financial statements, certified by a
          recognized firm of certified public accountants, within 120 days of
          fiscal year end or at such time as Debtor's Board of Directors
          receives the audit. If Debtor is a publicly held company, then Debtor
          agrees to provide quarterly and annual audited statements, certified
          by a recognized firm of certified public accountants, within 10 days
          after the statements are provided to the Securities and Exchange
          Commission ("SEC"). All such statements are to be prepared using
          generally accepted accounting principles ("GAAP") (except, with
          respect to unaudited financial statements, for the absence of
          footnotes and normal non-material year-end audit adjustments) and, if
          Debtor is a publicly held company, are to be in compliance with SEC
          requirements."

     6. FURTHER ASSURANCES.

     The fourth line of subsection (a) is hereby amended by adding the word
     "reasonably" before the words "necessary or advisable."

     The second line of subsection (c) is hereby amended by adding the word
     "reasonable" before the words "attorneys' fees" and the following words are
     hereby added to the end of subsection (c) after the word "Collateral" and
     before the period: ", but not for any claims caused by Secured Party's
     gross negligence or willful misconduct."

     7. DEFAULT AND REMEDIES.

     In the second line of subsection (a)(v), the words "when made and Debtor
     fails to cure such breach within thirty (30) days after written notice from
     Secured Party" are hereby added after the word "respect" and before the
     semicolon.

     In subsection (a)(vii), the words "beyond any applicable grace period" are
     hereby added after the word "default."

     In subsection (a)(xi), the words "forty-five (45)" are hereby replaced with
     the words "sixty (60)."

     In the third line of subsection (b), the words "eighteen percent (18%) are
     hereby replaced with the words "sixteen percent (16%)."

     In the first line of subsection (c), the word "After" is hereby replaced
     with the following: "Upon the occurrence and during the continuance of a."

     In the second line of subsection (d), the word "reasonable" is hereby added
     before the word "attorneys'."

     In the first line of subsection (e), the word "reasonable" is hereby added
     before the word "costs."

     8. MISCELLANEOUS.

     Subsection (c) is hereby amended and replaced with the following:

          (c) Secured Party may fill in the blanks left for dates and other
     blanks in this Agreement or any Collateral Schedule consistent with the
     agreement of the parties, but Secured party may not make any other
     correction without the consent of Debtor, which consent shall not be
     unreasonably withheld. If Secured Party requests Debtor to consent to any
     correction and Debtor does not respond to such request within ten days
     after receipt of such request, then Debtor shall be deemed to have
     consented to such correction.

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          The second line of subsection(g) is hereby amended by changing the
word "Connecticut" to "California."

          TERMS USED. BUT NOT OTHERWISE DEFINED HEREIN SHALL HAVE THE MEANINGS
GIVEN TO THEM IN THE AGREEMENT. EXCEPT AS EXPRESSLY AMENDED HEREBY, THE
AGREEMENT SHALL REMAIN IN FULL FORCE AND EFFECT. IF THERE IS ANY CONFLICT
BETWEEN THE PROVISIONS OF THE AGREEMENT AND THIS AMENDMENT, THEN THIS AMENDMENT
SHALL CONTROL.

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment
simultaneously with the Agreement by signature of their respective authorized
representative set forth below.

General Electric Capital Corporation                    Deltagen, Inc.


By: /s/ Barbara Kaiser                                  By: /s/ William Matthews
    ----------------------                                  --------------------
Name: Barbara Kaiser                                    Name: William Matthews
Title: EVP/General Manager                              Title: CEO