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                                                                 EXHIBIT 10.2.3


                     DELTAGEN, INC. 2000 STOCK INCENTIVE PLAN:
                        NONSTATUTORY STOCK OPTION AGREEMENT


NONSTATUTORY      This option is not intended to be an incentive stock option
STOCK OPTION      under section 422 of the Internal Revenue Code.


VESTING           Your Option vests over a four-year period as follows:  No
                  part of your Option will vest until you have performed
                  twelve months of Service from the Vesting Start Date.
                  Twenty Five percent (25%) of your Option vests when you
                  complete twelve months of Service from the Vesting Start
                  Date as shown on the cover sheet; the balance of your
                  Option will vest with respect to an additional 1/48 of the
                  Shares subject to the Option for each full month of Service
                  thereafter (rounded to the nearest whole share).  After
                  your Service has terminated for any reason, vesting of your
                  Option immediately stops.


TERM              Your Option will expire in any event at the close of
                  business at Deltagen headquarters on the day before the
                  10th anniversary of the Date of Grant shown on the cover
                  sheet (fifth anniversary for a 10% owner).  It will expire
                  earlier if your Deltagen service terminates, as described
                  below.


REGULAR           If your service as an employee, consultant or advisor of
TERMINATION       Deltagen (or any subsidiary) terminates for any reason
                  except death or total and permanent disability, then your
                  Option will expire at the close of business at Deltagen
                  headquarters on the 90th day after your termination date.


                  Deltagen determines when your service terminates for this
                  purpose.


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DEATH             If you die as an employee, consultant or advisor of
                  Deltagen or one of its subsidiaries, then your Option will
                  expire at the close of business at Deltagen headquarters on
                  the date six months after the date of death.  During that
                  six-month period, your estate or heirs may exercise your
                  option.


DISABILITY        If your service as an employee, consultant or advisor of
                  Deltagen (or any subsidiary) terminates because of your
                  total and permanent disability, then your Option will
                  expire at the close of business at Deltagen headquarters on
                  the date six months after your termination date.


LEAVES OF         For purposes of this Option, your service does not
ABSENCE           terminate when you go on a military leave, a sick leave or
                  another BONA FIDE leave of absence that was approved by
                  Deltagen in writing.   Your service terminates when the
                  approved leave ends, unless you immediately return to
                  active work.

                  Deltagen determines which leaves count for this purpose.


RESTRICTIONS ON   Deltagen will not permit you to exercise this Option if the
EXERCISE          issuance of shares at that time would violate any law.


NOTICE OF         When  you wish to exercise this Option, you must submit the
EXERCISE          form provided by Deltagen at the following address:


                       Deltagen, Inc.
                       1003 Hamilton Avenue
                       Menlo Park, CA 94025
                       Attn:  Stock Administration


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                  Facsimiles are not acceptable.  Your notice must specify
                  how many shares you wish to purchase  and how your shares
                  should be registered (in your name only or in your and your
                  spouse's names as community property or as joint tenants
                  with right of survivorship).  The notice will be effective
                  when it is received by Deltagen.

                  If someone else wants to exercise this Option after your
                  death, that person must prove to Deltagen's satisfaction
                  that he or she is entitled to do so.


FORM OF PAYMENT   When you submit your notice of exercise, you must include
                  payment of the option price for the shares you are
                  purchasing.  Payment may be made in one (or a combination
                  of two or more) of the following forms:

                  -    Your personal check, a cashier's check or a money
                       order.

                  -    Irrevocable directions to a securities broker approved
                       by Deltagen to sell your option shares and to deliver
                       all or a portion of the sale proceeds to Deltagen in
                       payment of the option price. The directions must be
                       given by signing the form provided by Deltagen.  The
                       balance of the sale proceeds, if any, will be
                       delivered to you.

                  -    Certificates for Deltagen stock that you have owned
                       for at least six months, along with any forms needed
                       to effect a transfer of the shares to Deltagen.  The
                       value of the shares, determined as of the effective
                       date of the option exercise, will be applied to the
                       option price.

WITHHOLDING       You will not be allowed to exercise this Option unless you
TAXES             make acceptable arrangements to pay any withholding taxes
                  that may be due as a result of the option exercise.


RESTRICTIONS ON   By signing this Agreement, you agree not to sell any option
RESALE            shares at a time when applicable laws or Deltagen policies
                  prohibit a sale.  This restriction will apply as long as
                  you are an employee of Deltagen or a subsidiary.


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TRANSFER OF       Prior to your death, only you may exercise this Option.
OPTION            You cannot transfer or assign this option.  For instance,
                  you may not sell this option or use it as security for a
                  loan.  If you attempt to do any of these things, this
                  option will immediately become invalid.  You may, however,
                  dispose of this Option in your will.

                  Regardless of any marital property settlement agreement,
                  Deltagen is not obligated to honor a notice of exercise
                  from your former spouse, nor is Deltagen obligated to
                  recognize your former spouse's interest in your Option in
                  any other way.


RETENTION RIGHTS  Your Option or this Agreement do not give you the right to
                  be retained by Deltagen or its subsidiaries in any
                  capacity.  Deltagen and its subsidiaries reserve the right
                  to terminate your service at any time, with or without
                  cause.


STOCKHOLDER       You, or your estate or heirs, have no rights as a
RIGHTS            stockholder of Deltagen until a certificate for your option
                  shares has been issued.  No adjustments are made for
                  dividends or other rights if the applicable record date
                  occurs before your stock certificate is issued, except as
                  described in the Plan.


ADJUSTMENTS       In the event of a stock split, stock dividend or a similar
                  change in Deltagen stock, the number of shares covered by
                  this Option and the exercise price per share may be
                  adjusted pursuant to the Plan.


APPLICABLE LAW    This  Agreement  will be interpreted and enforced under the
                  laws of the State of California.


THE PLAN AND      The text of the Deltagen, Inc. 2000 Stock Incentive Plan is
OTHER AGREEMENTS  incorporated in this Agreement by reference.  This
                  Agreement and the Plan constitute the entire understanding
                  between you and Deltagen regarding this Option.  Any prior
                  agreements, commitments or negotiations concerning this
                  option are superseded.


          BY SIGNING THE COVER SHEET OF THIS AGREEMENT, YOU AGREE TO ALL
          OF THE TERMS AND CONDITIONS DESCRIBED ABOVE AND IN THE PLAN.


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