<PAGE>

                                                                   Exhibit 10.47

                        DELTAGEN, INC. CHANGE OF CONTROL
                         SEVERANCE PAY PLAN FOR OFFICERS

     1.  Introduction. The purpose of this Deltagen, Inc. Change of Control
Severance Pay Plan For Officers (the "Plan") is to provide Severance Benefits to
Covered Executives whose employment is terminated in an Eligible Termination.
This document constitutes both the written instrument under which the Plan is
maintained and the Plan's summary plan description.

     2.  Important Terms. To help you understand how this Plan works, it is
important to know the following terms:

         2.1 "Administrator" means the Company, or any person or committee to
whom the Company has delegated any authority or responsibility pursuant to
Section 7, but only to the extent of such delegation.

         2.2 "Cause" means:

         (a) any intentional action or intentional failure to act by the Covered
     Executive which was performed in bad faith and to the material detriment of
     the Company;

         (b) the willful and habitual neglect of the Covered Executive's duties
     of employment; or

         (c) the conviction of a Covered Executive of a felony crime involving
     moral turpitude,

provided that in the event that any of the foregoing events is capable of being
cured, the Company shall provide written notice to the Covered Executive
describing the nature of such event and Executive shall thereafter have five (5)
business days to cure such event.

         2.3 "Change of Control" means the occurrence of either of the following
events:

         (a) A change in the composition of the board of directors of the
     Company (the "Board"), as a result of which fewer than one-half of the
     incumbent directors are directors who either:

             (i)  Had been directors of the Company twenty-four (24) months
         prior to such change; or

             (ii) Were elected, or nominated for election, to the Board with the
         affirmative votes of at least a majority of the directors who had been
         directors of the Company twenty-four (24) months prior to such change
         and who were still in office at the time of the election or nomination;
         or

<PAGE>

                  (b)  Any "person" (as such term is used in sections 13(d) and
         14(d) of the Securities Exchange Act of 1934, as amended) who by the
         acquisition or aggregation of securities, is or becomes the beneficial
         owner, directly or indirectly, of securities of the Company
         representing fifty percent (50%) or more of the combined voting power
         of the Company's then outstanding securities ordinarily (and apart from
         rights accruing under special circumstances) having the right to vote
         at elections of directors (the "Base Capital Stock"); except that any
         change in the relative beneficial ownership of the Company's securities
         by any person resulting solely from a reduction in the aggregate number
         of outstanding shares of Base Capital Stock, and any decrease
         thereafter in such person's ownership of securities, shall be
         disregarded until such person increases in any manner, directly or
         indirectly, such person's beneficial ownership of any securities of the
         Company. For purposes of this Subsection (b), the term "person" shall
         not include an employee benefit plan maintained by the Company.

Notwithstanding the foregoing, the term "Change of Control" shall not include a
transaction, the sole purpose of which is to change the state of the Company's
incorporation.

                  2.4  "Company" means Deltagen, Inc., a Delaware corporation
and any successor by merger, acquisition, consolidation or otherwise that
assumes the obligations of the Plan and any domestic subsidiaries of Deltagen,
Inc.

                  2.5  "Covered Executive" means any officer of the Company who
receives a written Notice of Eligibility from the Company.

                  2.6  "Eligible Termination" means any termination within
twelve (12) months following a Change of Control of the Company (other than for
disability or death) of a Covered Executive's employment (a) by the Company for
any reason other than Cause; or (b) by the Covered Executive for Good Reason.

                  2.7  "Eligible Termination Date" means the effective date of a
Covered Executive's Eligible Termination.

                  2.8  "ERISA" means the Employee Retirement Income Security Act
of 1974, as amended.

                  2.9  "Good Reason" means the Company has, without the written
consent of the Covered Executive:

                  (a)  Reduced the powers, duties or title of the Covered
         Executive;

                  (b)  Reduced the Covered Executive's base salary; or

                  (c)  Required the Covered Executive to relocate his or her
         principal place of business by more than 40 miles from its location
         immediately prior to the Change of Control.

                  2.10 "Notice of Eligibility" means a written notice from the
Company delivered to an individual establishing that the individual is a Covered
Executive under the Plan.

                                        2

<PAGE>

                  2.11 "Plan" means the Deltagen, Inc. Change of Control
Severance Pay Plan For Officers, as set forth in this document, and as hereafter
amended from time to time.

                  2.12 "Severance Benefit" means the benefits the Covered
Executive will be provided pursuant to Section 4 and Appendix A.

         3.       Eligibility. An individual shall become a participant in the
Plan only if he or she receives a Notice of Eligibility. Such a Covered
Executive shall be eligible for a Severance Benefit under the Plan, only if he
or she is also a Covered Executive on his or her Eligible Termination Date.

         4.       Payment of Severance Benefit.

                  4.1  Severance Benefit. A Covered Executive who is eligible to
receive a Severance Benefit under and subject to the terms of Section 3 will
receive such benefit in the amount determined in accordance with Appendix A.

                  4.2  Release. As a condition to receiving any Severance
Benefit under this Plan, each Covered Executive will be required to sign a
waiver and general release of all claims arising out of his or her Eligible
Termination and employment with the Company and its subsidiaries and affiliates,
in a form satisfactory to the Legal Department of the Company.

         5.       Withholding. All federal, state, local and other taxes and any
other required payroll deductions will be withheld from any Severance Benefit.

         6.       Administration. The Company is the Administrator of the Plan
(within the meaning of section 3(16)(A) of ERISA) and has the power to
administer and interpret the Plan in its sole discretion. The Administrator is
the "named fiduciary" of the Plan for purposes of ERISA and will be subject to
the fiduciary standards of ERISA when acting in such capacity. Any decision made
or other action taken by the Administrator with respect to the Plan, and any
interpretation by the Administrator of any term or condition of the Plan, or any
related document, will be conclusive and binding on all persons and be given the
maximum possible deference allowed by law. The Administrator may delegate in
writing to any other person all or any portion of his or her authority or
responsibility with respect to the Plan.

         7.       Amendment or Termination. The Company reserves the right, by
written action to amend, modify or terminate the Plan at any time, without
advance notice to any Covered Executive. Any action of the Company in amending
or terminating the Plan will be taken in a non-fiduciary capacity.
Notwithstanding the foregoing, however, within the period commencing six (6)
months prior to a Change of Control and ending eighteen (18) months after such
Change of Control, no amendment or termination of the Plan shall be effective
without the written consent of an affected Covered Executive if the affect of
the amendment or termination would result in the reduction of the benefits the
Covered Executive would have received had the Plan's provisions in effect
immediately prior to such amendment or termination been applied to the Covered
Executive.

         8.       Claims Procedure. Any employee or other person who believes he
or she is entitled to any payment under the Plan may submit a claim in writing
to the Administrator. If the

                                       3

<PAGE>

claim is denied (in full or in part), the claimant will be provided a written
notice explaining the specific reasons for the denial and referring to the
provisions of the Plan on which the denial is based. The notice will describe
any additional information needed to support the claim, describe the Plan's
appeal procedure, and will also inform the claimant of his or her right to file
a civil lawsuit under section 502(a) of ERISA if the claimant's appeal is
denied. The denial notice will be provided within 90 days after the claim is
received. If special circumstances require an extension of time (up to 90 days),
written notice of the extension will be given within the initial 90-day period.

         9.       Appeal Procedure. If the claimant's claim is denied, the
claimant (or his or her authorized representative) may apply in writing to the
Administrator for a review within 60 days after the claimant received the
decision denying the claim. The claimant (or representative) then has the right
to review, and receive at no charge copies of documents, records, and other
information relevant to the claimant's claim for benefits, and to submit issues
and comments in writing. The Administrator will provide written notice of his or
her decision on review within 60 days after it receives a review request. If
additional time (up to 60 days) is needed to review the request, the claimant
(or representative) will be given written notice of the reason for the delay. If
the appeal is denied (in full or part), the claimant will be provided a written
notice explaining the specific reasons for the denial and referring to the
provisions of the Plan on which the denial is based. The notice will inform the
claimant of his or her right to review, and receive at no charge copies of
documents, records and other information relevant to claimant's claim for
benefits, and will also inform the claimant of his or her right to file a civil
lawsuit under section 502(a) of ERISA.

         10.      Source of Payments. All Severance Benefits will be paid in
cash from the general funds of the Employer; no separate fund will be
established under the Plan; and the Plan will have no assets. Because the Plan
has no assets, there are no assets to be allocated in the event of a Plan
termination. No right of any person to receive any payment under the Plan will
be any greater than the right of any other general unsecured creditor.

         11.      Inalienability. In no event may any current or former employee
of the Company or any of its subsidiaries or affiliates sell, transfer,
anticipate, assign or otherwise dispose of any right or interest under the Plan.
At no time will any such right or interest be subject to the claims of creditors
nor liable to attachment, execution or other legal process.

         12.      No Enlargement of Employment Rights. Neither the establishment
or maintenance of the Plan, any amendment of the Plan, nor the making of any
benefit payment hereunder, will be construed to confer upon any individual any
right to be continued as an employee of the Company. The Company expressly
reserves the right to discharge any of its employees at any time, with or
without cause.

         13.      Applicable Law. The provisions of the Plan will be construed,
administered and enforced in accordance with ERISA and, to the extent
applicable, the laws of the State of California.

                                       4

<PAGE>

     14. Severability. If any provision of the Plan is held invalid or
unenforceable, its invalidity or unenforceability will not affect any other
provision of the Plan, and the Plan will be construed and enforced as if such
provision had not been included.

     15. Headings. Headings in this Plan document are for purposes of reference
only and will not limit or otherwise affect the meaning hereof.

     16. Indemnification. The Company hereby agrees to indemnify and hold
harmless the officers and employees of the Company, and the members of its board
of directors, from all losses, claims, costs or other liabilities arising from
their acts or omissions in connection with the administration, amendment or
termination of the Plan, to the maximum extent permitted by applicable law. This
indemnity will cover all such liabilities, including judgments, settlements and
costs of defense. The Company will provide this indemnity from its own funds to
the extent that insurance does not cover such liabilities.

     17. Additional Information.

         Plan Name:                   Deltagen, Inc. Change of Control Severance
                                      Pay Plan for Officers

         Plan Sponsor:                Deltagen, Inc.
                                      740 Bay Road
                                      Redwood City, CA 94063

         Identification Numbers:      EIN:  ______________________
                                      PLAN:  50__

         Plan Year:                   Calendar year

         Plan Administrator:          Deltagen, Inc.
                                      740 Bay Road
                                      Redwood City, CA 94063
                                      650-569-5100

         Agent for Service of         Deltagen, Inc.
         Legal Process:               740 Bay Road
                                      Redwood City, CA 94063

     18. Statement of ERISA Rights.

         As a Covered Executive under the Plan, you have certain rights and
protections under ERISA:

               (a) You may examine (without charge) all Plan documents,
including any amendments and copies of all documents filed with the U.S.
Department of Labor, such as

                                        5

<PAGE>

the Plan's annual report (IRS Form 5500). These documents are available for your
review in the Company's Human Resources Department.

                    (b) You may obtain copies of all Plan documents and other
Plan information upon written request to the Plan Administrator. A reasonable
charge may be made for such copies.

               In addition to creating rights for Covered Executives, ERISA
imposes duties upon the people who are responsible for the operation of the
Plan. The people who operate the Plan (called "fiduciaries") have a duty to do
so prudently and in the interests of you and the other Covered Executives. No
one, including the Company or any other person, may fire you or otherwise
discriminate against you in any way to prevent you from obtaining a benefit
under the Plan or exercising your rights under ERISA. If your claim for a
severance benefit is denied, in whole or in part, you must receive a written
explanation of the reason for the denial. You have the right to have the denial
of your claim reviewed. (The claim review procedure is explained in Sections 8
and 9 above.)

               Under ERISA, there are steps you can take to enforce the above
rights. For instance, if you request materials and do not receive them within 30
days, you may file suit in a federal court. In such a case, the court may
require the Plan Administrator to provide the materials and to pay you up to
$110 a day until you receive the materials, unless the materials were not sent
because of reasons beyond the control of the Plan Administrator. If you have a
claim which is denied or ignored, in whole or in part, you may file suit in a
state or federal court. If it should happen that you are discriminated against
for asserting your rights, you may seek assistance from the U.S. Department of
Labor, or you may file suit in a federal court.

               In any case, the court will decide who will pay court costs and
legal fees. If you are successful, the court may order the person you have sued
to pay these costs and fees. If you lose, the court may order you to pay these
costs and fees, for example, if it finds that your claim is frivolous.

               If you have any questions regarding the Plan, please consult the
Company's Human Resources Department. If you have any questions about this
statement or about your rights under ERISA, you may contact the nearest area
office of the Pension and Welfare Benefits Administration, U.S. Department of
Labor listed in your telephone directory, or the Division of Technical
Assistance and Inquiries, Pension and Welfare Benefits Administration, U.S.
Department of Labor, 200 Constitution Avenue, NW, Washington, DC 20210. You may
also obtain certain publications about your rights and responsibilities under
ERISA by calling the publications hotline of the Pension and Welfare Benefits
Administration.

                                       6

<PAGE>

     19.  Execution.

          In Witness Whereof, the Company, by its duly authorized officer, has
executed this Plan on the date indicated below.

                                    DELTAGEN, INC.

                                    By _________________________________________

                                    Title ______________________________________

                                    Date _______________________________________


                                       7

<PAGE>

                                   APPENDIX A

If a Covered Executive is entitled to a Severance Benefit under the Plan, the
amount shall be determined in accordance with this Appendix A.

     1.   Base Pay. The Employer will make a payment equal to six (6) months of
the Covered Executive's regular base pay in effect on his or her Eligible
Termination Date, payable in a lump sum payment within seven (7) days after the
effective date of the Covered Executive executing the general release described
in Section 4.2 of the Plan. The amount payable pursuant to this Section 1 shall
be reduced (but not below $0) by any amount which is determined based on a
Covered Executive's base pay and which is payable as severance under any other
plan, agreement, arrangement or other program (including, but not limited to any
written employment agreement).

     2.   Bonus Payments. The Employer will make a payment equal to the pro-rata
portion of any bonus that would have been earned for the year in which the
Covered Executive's Eligible Termination occurs. This amount shall be determined
by multiplying the amount the bonus would otherwise have equaled (determined by
the Board of Directors based on economic and performance duties through the
effective date of the Eligible Termination by a fraction, the numerator of which
is the portion of the year preceding the Eligible Termination and the
denominator of which is one (1). The amount payable pursuant to this Section 2
of Appendix A shall be reduced (but not below $0) by any amount which is
determined based on a Covered Executive's bonus amounts and which is payable as
severance under any other plan, agreement, arrangement or other program
(including, but not limited to any written employment agreement).

     3.   COBRA Premiums. The Employer will reimburse the COBRA premiums on a
Covered Executive's health care coverage in effect on his or her Eligible
Termination Date for a period equal to the number of months of severance pay
which is payable pursuant to Section 1 of this Appendix A. This period of time
shall be reduced (but not below $0) by any period for which COBRA premiums are
reimbursed under any other plan, agreement, arrangement or other program
(including, but not limited to any written employment agreement).
Notwithstanding the preceding, no COBRA premium shall be reimbursed until the
effective date of the general release described in Section 4.2 of the Plan.

     4.   Loan Forgiveness. Any amount that remains unpaid on any relocation
loan entered into between the Covered Executive and the Employer or Company
shall be forgiven; provided the loan is not otherwise in default on the Covered
Employee's Eligible Termination Date. This loan forgiveness shall be effective
on (and subject to) the effective date of the general release described in
Section 4.2 of the Plan and shall also be subject to the Covered Executive's
payment of any payroll or withholding taxes due with respect to such
forgiveness.