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                                                                  EXHIBIT 10.51

                                    AGREEMENT

     This Agreement (the "Agreement") is entered into as of February 14, 2003
(the "Execution Date") by and between Deltagen, Inc., a Delaware corporation
(the "Company"), and Mark Moore, Ph.D. ("Executive") (together "the Parties").

     WHEREAS, Executive is employed by the Company as Chief Scientific Officer
pursuant to the terms of an employment agreement dated April 7, 2000 (the
"Employment Agreement");

     WHEREAS, the Company made a full recourse loan to Executive evidenced by
that certain promissory note dated March 16, 2000 (the "Promissory Note") in the
original principal amount of $268,350 (the "Loan");

     WHEREAS, as of February 14, 2003, the Loan had an outstanding balance
(principal and interest) of $320,893.67;

     WHEREAS, the Loan has a maturity date of March 16, 2004 (the "Maturity
Date");

     WHEREAS, the Loan is secured by the underlying shares that the Executive
purchased with the Loan proceeds; and

     WHEREAS, the Company has agreed to provide certain retention bonuses to
Executive, to settle the Loan and to offer an option exchange to Executive.

     NOW, THEREFORE, in consideration of the mutual promises contained herein,
the Parties agree as follows:

     1.   Promissory Note.

          The Promissory Note is eligible for prepayment, in whole or in part,
at Executive's election without penalty, fee or acceleration pursuant to the
terms of the Promissory Note. Both Parties desire that Executive fully repay his
obligations under the Promissory Note on the Execution Date. The following shall
occur on the Execution Date in full satisfaction of Executive's accumulated debt
of $320,893.67, which represents the outstanding balance of the loan as of the
Execution Date:

          (a)  The Company shall repurchase all 53,573 unvested shares pledged
to the Promissory Note at their original cost of $1.5662 per share. The
aggregate repurchase amount of $83,906.03 shall be applied by the Company to
repay accrued unpaid interest and principal on the Promissory Note;

          (b)  All 117,855 vested shares pledged to the Promissory Note shall be
repurchased by the Company using the Company's closing share price of $0.299 on
the Execution Date, and the proceeds of such repurchase shall be applied by the
Company and Executive to repay accrued unpaid interest and principal on the
Promissory Note; and

          (c)  Executive shall transfer the number of Company common shares to
the Company needed (up to a maximum of 674,746 shares) to fully off pay any
remaining accrued interest and principal on the Promissory Note. Such
transferred shares shall be valued using the Company's closing share price of
$0.299 on the Execution Date. If there is any outstanding balance on the
Promissory Note after such transfer of shares, then such balance shall be paid
in cash by Executive on the Execution Date.

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     2.   Retention Bonus.

          (a)  Bonus Amount; Duration. The Company agrees to pay Executive a
retention bonus of fifteen thousand dollars ($15,000) per month (each, a
"Retention Bonus") for a nine-month period beginning on the Execution Date.

          (b)  Payment Dates. The initial Retention Bonus shall be paid on the
Execution Date and subsequent Retention Bonus payments shall occur on the
following dates in 2003: March 14, April 14, May 14, June 13, July 14, August
14, September 12, October 14 and November 14; provided, however, that no
Retention Bonus shall be due and payable if the date of payment of such
Retention Bonus is after the date of the termination of Executive's employment
with the Company under one or more clauses of the Employment Agreement, where
such termination is for Cause as defined in the Employment Agreement.

     3.   Option Exchange. All 488,356 of Executive's outstanding stock options
having a per-share exercise price that is greater than $0.31 shall be
surrendered to the Company in exchange for 341,849 shares of restricted Company
common stock pursuant to the Company's option exchange program, and the
restricted stock agreement attached hereto as Exhibit A, provided that Executive
tender payment of $341.85, the par value of such shares, to the Company on the
date the options are tendered.

     4.   Taxes. Any tax obligations of Executive (and tax liability therefor)
relating to any of the above transactions, including any penalties and interest
based upon such tax obligations are entirely the responsibility and liability of
Executive and all tax withholding requirements if any must be timely satisfied
by Executive. All payments made pursuant to this Agreement shall be conditioned
on Executive's satisfaction of such withholding.

     5.   Employment Agreement. Nothing herein provides Executive with any right
of continued employment and Company may exercise any termination rights under
the Employment Agreement notwithstanding this Agreement. This Agreement does not
form a part of and shall not be integrated with the Employment Agreement. The
Employment Agreement shall continue in full force and effect notwithstanding the
effectiveness or termination of this Agreement.

     6.   Severability. Whenever possible, each provision of this Agreement will
be interpreted in such a manner as to be effective and valid under applicable
law, but if any provision of this Agreement is held to be invalid, illegal or
unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect
any other provision or any other jurisdiction, but this Agreement will be
reformed, construed and enforced in such jurisdiction as if such invalid,
illegal or unenforceable provision had never been contained herein.

     7.   Counterparts. This Agreement may be executed in counterparts, each of
which will be deemed an original, and which together will be a single
instrument.

     8.   No Representations. Each Party represents that it has had the
opportunity to consult with an attorney, and has carefully read and understands
the scope and effect of the provisions of this Agreement. Neither Party has
relied upon any representations or statements made by the other party hereto
which are not specifically set forth in this Agreement.

     9.   Authority. The Company represents and warrants that the undersigned
has the authority to act on behalf of the Company and to bind the Company and
all who may claim through it to the terms and conditions of this Agreement.
Executive represents and warrants that he has the capacity to act on his

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own behalf and on behalf of all who might claim through him to bind them to the
terms and conditions of this Agreement.

     10.  Voluntary Execution of Agreement. This Agreement is executed
voluntarily and without any duress or undue influence on the part or behalf of
the Parties hereto, with the full intent of releasing all claims. The Parties
acknowledge that:

          (a)  They have read this Agreement;

          (b)  They have been represented in the preparation, negotiation, and
execution of this Agreement by legal counsel of their own choice or that they
have voluntarily declined to seek such counsel;

          (c)  They understand the terms and consequences of this Agreement and
of the releases it contains;

          (d)  They are fully aware of the legal and binding effect of this
Agreement.

     11.  Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of California, without regard to the
conflicts of law principles thereof.

     IN WITNESS WHEREOF, the Parties hereto have executed this Agreement as of
the day and year first above written.



___________________________________     DELTAGEN, INC.
MARK MOORE, PH.D., EXECUTIVE

                                        By: _________________________________

                                        Name: _______________________________

                                        Title: ______________________________

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