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                                                                   Exhibit 10.43

                                 PROMISSORY NOTE

U.S.$630,000                                          Redwood City, California
                                                      June 24, 2002

         For value received, the undersigned (collectively, "Borrowers") jointly
and severally promise to pay to the order of Deltagen, Inc., a Delaware
corporation ("Payee"), located at 740 Bay Rd, Redwood City, California, 94063 or
at such a place as Payee may designate in writing, the sum of Six Hundred Thirty
Thousand United States Dollars (U.S. $630,000).

         This Promissory Note is made and executed by Borrowers pursuant to a
certain written Loan Agreement ("Agreement") between Payee and Borrowers dated
June 24, 2002, all of the provisions of which are incorporated herein by this
reference, and is subject to all terms and provisions thereof, including
specifically the provisions of Paragraphs 1 and 2 thereof which provide, inter
alia, (a) the date upon which this Promissory Note matures and becomes due and
payable, and (b) the date and conditions upon which this Promissory Note will
bear interest, the amount thereof and the payment due dates with respect to
principal and interest. Borrowers jointly and severally agree to all such
incorporated provisions and that the covenants on the part of Borrowers to be
performed pursuant to said Agreements constitute covenants on the part of the
Borrowers to be performed hereunder.

         This Promissory Note is secured by a Deed of Trust covering certain
improved real property as more particularly described in the Agreement ("Real
Property"), such Deed of Trust being subject to and subordinate under a certain
Bridge Note described in the Agreement. In the event that Borrowers at any time
prior to payment and discharge in full of this Promissory Note shall, with the
exception of such Bridge Note, sell, encumber, convey, or alienate the Real
Property or any part thereof, or any interest therein, or shall be divested of
title or any interest therein in any manner or way, whether voluntarily or
involuntarily, without the written consent of Payee being first had and
obtained, Payee shall have the right, at its option, except as prohibited by
law, to declare any indebtedness or obligations hereunder, irrespective of the
maturity date hereof, immediately due and payable.

         Except as otherwise prohibited by law, the Borrowers hereby expressly
waive presentment, demand for payment, dishonor, protest, notice of protest and
any other formality. Borrowers jointly and severally promise to pay all costs of
enforcement hereof, including attorneys' fees.

                                                   /s/ Michael Sember
                                                   -----------------------------
                                                   EMPLOYEE NAME

                                                   /s/ W. Kay Sember
                                                   -----------------------------
                                                   SPOUSE NAME<PAGE>

                                                                   Exhibit 10.44

                                 LOAN AGREEMENT

This Agreement is made and entered into as of this 24/th/ day of June, 2002 by
and between Deltagen Inc., a Delaware corporation ("Deltagen"), and Michael T.
Sember ("Sember") and his spouse, Kay Sember (Michael Sember and Kay Sember are
referred to herein collectively as "Borrowers").

                                    Recitals

     A. Sember has been  employed by Deltagen to perform  certain  services as
an employee of Deltagen, as Deltagen may from time to time direct;

     B. In Deltagen's anticipation of future performance of substantial services
by Sember for Deltagen, Deltagen is willing to render financial assistance to
Borrowers in the form of a loan to Borrowers to assist them in purchasing a
principal residence located at 348 Lennox Avenue, Menlo Park, California, 94025
(the "Residence"); and

     C. The loan from Deltagen to Borrowers will be secured in whole or
substantial part by a deed of trust on the residence, all as more fully set
forth herein.

NOW, THEREFORE, in view of the foregoing recitals and the following covenants
and obligations, Deltagen and Borrowers do hereby mutually agree as follows:

     1. Loan. Deltagen agrees to loan to Borrowers the sum of Six Hundred Thirty
Thousand United States Dollars ($630,000) (the "Loan"), which shall be made on
the following terms and conditions:

        (a) The Loan will be applied solely and entirely toward the purchase
price of the Residence, and the Borrowers agree to so apply such proceeds;

        (b) The Loan will bear interest as provided in Paragraph 2.1 of this
Agreement; all payments made on account thereof shall be credited first to
accrued and unpaid interest and the balance, if any, to unpaid principal;

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        (c) The principal amount of Five Hundred Fifty-Two Thousand United
States Dollars ($552,000) of the Loan and the interest on that portion of the
Loan will be forgiven on the fifth anniversary of the start date of Sember's
employment with Deltagen;

        (d) The principal amount of Seventy-Eight Thousand United States Dollars
($78,000) of the Loan shall become due and payable with interest on the fifth
anniversary of the start date of Sember's employment with Deltagen, except as
otherwise set forth in Paragraphs 2.2 and 2.4 of this Agreement;

        (e) Borrowers shall be fully responsible for all taxes due related to
the Loan and interest on the Loan;

        (f) Borrowers may repay the Loan in full or in part at any time without
premium or penalty; and

        (g) The Loan shall be evidenced by a certain Promissory Note in the form
of Exhibit A attached hereto and secured in whole or substantial part by a deed
of trust ("Deed of Trust") in the form of Exhibit B attached hereto to
constitute a lien on Residence subject only to: (i) the exceptions as specified
in the title report of First American Trust Company, dated as of April 26, 2002
and issued under its Escrow Number 555568; (ii) a first mortgage loan on the
Residence; and (iii) a deed of trust held by First Republic Bank in connection
with a certain 12-month loan note between First Republic Bank and the Borrowers
dated June 18, 2002 ("Bridge Note") in the form of Exhibit C attached hereto. A
condition of Deltagen's obligation hereunder to fund the Loan shall be its
contemporaneous receipt upon funding of a California Land Title Association
standard lender's policy of title insurance in the amount of the Loan assuring
Deltagen that the Deed of Trust constitutes a lien on the Residence subject only
to the exceptions set forth in the preceding sentence. The Borrowers shall make
reasonable efforts to satisfy the Bridge Note, including reasonable efforts: (a)
to consummate sale of the Borrowers' current home located at 14 Norfield Farm
Lane, Weston, Connecticut 06883 and (b) to apply the proceeds of such sale
towards satisfaction of the Bridge Note. Deltagen's security lien on the
Residence shall be $500,000 until satisfaction of the Bridge Note, upon which
the security lien will be in the full amount of the Loan. And, upon satisfaction
of the Bridge Note, the Deed of Trust shall constitute a second lien on the
Residence, subject only to exceptions (i) and (ii) set forth above.

    2.  Repayment.  Notwithstanding  the foregoing  terms set forth in Paragraph
1 above, the Loan shall become due and payable according to the following terms:

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        2.1 Interest. The Loan shall bear interest from the date of this
Agreement, and Borrowers hereby agree to pay the same, at an annual rate equal
to the rate announced by J.P. Morgan Chase & Co., Inc. as its Prime Rate.
Interest on the amount of $552,000 will be forgiven at the end of five (5) years
of continued employment of Sember by Deltagen. Upon the date of Sember's
voluntary resignation or termination for "Cause" (as defined in Paragraph 2.3),
the Loan will become interest-bearing at the Prime Rate plus 2 percentage
points, but not in excess of the maximum rate permitted by law, and shall begin
to accrue immediately and shall become due and payable within a reasonable
period not to exceed six (6) months of the date of Sember's voluntary
resignation or termination for Cause.

        2.2 Principal. All outstanding and unpaid principal shall become due and
payable (to the extent not previously forgiven) upon the earlier to occur of (i)
five (5) years from the start date of Sember's employment with Deltagen, or (ii)
six (6) months from the date of Sember's voluntary resignation or termination
for Cause. The forgivable portion of the original principal amount of the Loan,
$552,000, shall be forgiven (and Borrowers relieved of liability to Deltagen) on
the fifth anniversary of the start date of Sember's employment with Deltagen,
provided that Sember has remained continuously employed through such date.

        2.3 Termination of Employment. For purposes of this Agreement,
"Termination" of Sember's employment shall include termination for any reason or
no reason with or without cause, including death. Termination shall be for
"Cause" in the event of the occurrence of any of the following: (a) any
intentional action or intentional failure to act by Sember which was performed
in bad faith and to the material detriment of the Company; (b) Sember
intentionally refuses or intentionally fails to act in accordance with any
lawful and proper direction or order of the Company; (c) Sember willfully and
habitually neglects the duties of employment; or (d) Sember is convicted of a
felony crime.

        2.4 If Sember is terminated for any reason other than voluntary
resignation or termination for Cause, the Loan principal and interest will be
forgiven.

     3. Additional Assurances. Deltagen and Borrowers hereby mutually
acknowledge and agree that this Agreement does not constitute an employment
agreement between Deltagen and Sember, provided nevertheless that Deltagen and
Sember understand that Deltagen is making the Loan on the condition of its
expectation of future performance of substantial services by Sember.

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   4.   Miscellaneous.

        (a) This Agreement constitutes the entire understanding and agreement
between the parties relative to the subject matter hereof and supersedes all
prior oral or written understandings between them. It may not be modified or
amended except by a writing signed by each of them.

        All notices to be given under this Agreement shall be considered
delivered five days after a mailing by fully prepaid certified or registered
mail or when delivered to a party, whichever is earlier. Such notices shall be
sent to the following addresses:

          To Deltagen:          Deltagen, Inc
                                740 Bay Road
                                Redwood City, California 94063
                                Attention:  Sr. VP and General Counsel
                                Cc:  Chief Financial Officer

          To Borrowers:         Michael T. Sember
                                Kay Sember
                                348 Lennox Avenue
                                Menlo Park, California 94025

or to such other place as a party may by ten days written notice designate to
the other party.

        (c) This Agreement shall be governed by the Laws of the State of
California, as applied to contracts made, entered and to be performed entirely
within California.

        (d) The benefits and obligations of this Agreement, including the Loan
and repayment thereof, are not transferable by Borrowers.

     IN WITNESS WHEREOF, the parties hereto have executed this Loan Agreement as
of the date first above appearing.

                                        DELTAGEN, INC.

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                                             /s/  Richard H. Hawkins
                                             -----------------------------------
                                             Richard H. Hawkins
                                             Chief Financial Officer

BORROWERS:

/s/ Michael Sember
----------------------------
EMPLOYEE NAME

/s/ W. Kay Sember
----------------------------
SPOUSE NAME

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