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                                                            EXHIBIT 10.29



                                               Monsanto
                                               ----------------------------
                                               Monsanto Company
RICHARD J. MAHONEY                             800 N. Lindbergh Boulevard
Chairman and                                   St. Louis, Missouri 63167
Chief Executive Officer                        Phone: (314) 694-3756






                                February 1, 1989





Dr. Philip Needleman
Monsanto Company
800 North Lindbergh Boulevard
St. Louis, Missouri 63167

Dear Philip:

It is my pleasure to advise you that the Executive Compensation and
Development Committee of the Board ("ECDC") at its October 28, 1988
meeting, reviewed the retirement benefits which will be available to you
under the Company's Salaried Employees' Pension Plan ("Pension Plan")
and the Monsanto ERISA Parity Pension Plan. In recognition of the
experience and expertise which you have brought to the Company,
including 21 years of service with Washington University, and in
recognition of your potential service with the Company, the ECDC has
determined to award you, subject to certain conditions, a Supplemental
Retirement Benefit equal to 14% of your "Average Total Earnings", as
defined in the Pension Plan.  Except as specifically provided below, the
Supplemental Retirement Benefit will not be payable unless you accrue at
least ten years of vesting service with Monsanto. Any optional payment
form you elect under the Parity Pension Plan will also apply to the
Supplemental Retirement Benefit, using the same actuarial factors as are
used under the Pension Plan.

If you choose to do so, you may request deferral of your Supplemental
Retirement Benefit if you make a timely request prior to retirement. The
terms and conditions of this deferral option are described in Attachment
A, which is hereby incorporated in this agreement.



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If you die while employed, and your wife survives you, she will be
entitled to receive a survivor's benefit equal to 50% of this
Supplemental Retirement Benefit. In addition, if your widow is not yet
eligible for a survivor benefit under the Pension and Pension Parity
Plans, she would receive from this Supplemental Retirement Benefit a 50%
survivor benefit based on the actual benefit accrued to the date of your
death under these Plans. Each of these survivor benefits will be subject
to the normal reductions provided in the Pension Plans. Such survivor's
benefits would be payable for the remainder of your wife's lifetime.

If you Terminate Employment with the Company after a Change of Control
of the Company but before you attain ten years of Vesting Service, you
will be entitled to a monthly Supplemental Retirement Benefit equal to
14% of your Average Total Earnings multiplied by a fraction, the
numerator of which is your actual years of Vesting Service and the
denominator of which is 10. The benefit will be payable to you
commencing on the first day of the month following the later of your
Termination or your attainment of age 55. Alternatively, you may elect
to receive the actuarially commuted value of your Supplemental
Retirement Benefit, or a portion thereof, in a single sum, in which
case, the value of your Supplemental Retirement Benefit will be
calculated by the Qualified Actuary for the Salaried Pension Plan who
was serving as such immediately prior to the Change of Control using the
actuarial assumptions applicab1e to the Plan. The amount so calculated
by the Qualified Actuary will be paid to you in a single sum as soon as
practicable after you Terminate Employment.

This Supplemental Retirement Benefit will, be separate from and in
addition to any pension benefit which you are entitled to receive under
the Company's Pension Plan.

This Supplemental Retirement Benefit is provided and continued at the
sole discretion of the ECDC and may be terminated in whole or in part at
any time for reasons such as, but not limited to, your subsequent
employment with a chemical, pharmaceutical or other company in
competition with Monsanto, or your engaging in activities deemed by the
ECDC not to be in the best of interest of Monsanto. This Supplemental
Retirement Benefit may not be assigned either by you or your spouse, and
any attempted assignment, pledge or other transfer shall be void. If any
court, agency, or other party orders or is otherwise successful in
obtaining an order for transfer in whole or in part of the Supplemental
Retirement Benefit, it shall thereupon be deemed automatically
terminated in full.



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I am pleased to be able to offer this Supplemental Retirement Benefit on
behalf of the Company. Please acknowledge your receipt and acceptance of
this agreement by signing and returning one copy to my office.

                                      Very truly yours,

                                      MONSANTO COMPANY


                                      By /s/ Richard J. Mahoney
                                        ------------------------------
                                             Richard J. Mahoney
                                             Chairman and Chief
                                             Executive Officer

Received and Acknowledged:


/s/ Philip Needleman
----------------------------
Philip Needleman PhD.

Date: 2/1/89
     -------


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                                                            Attachment A
                                                                  2/1/89

                          PHILIP R. NEEDLEMAN
                SUPPLEMENTAL RETIREMENT BENEFIT AGREEMENT

Supplemental Retirement Benefit Deferral Option
-----------------------------------------------

You may request deferral of your Supplemental Retirement Benefit if you
submit a timely request at least six months prior to retirement. The
ECDC will consider your deferral request, and if it is approved, you
will be permitted to defer payment of your Supplemental Retirement
Benefit on the same terms and conditions as permitted under the ERISA
Pension Parity Plan ("Parity Plan"). For this reason, the terms and
conditions of the Parity Plan are incorporated by reference herein and
made a part of this Agreement.

In making any request to defer the Supplemental Retirement Benefit under
the Agreement, you may request that the Company measure the return on
all or a portion of any deferred amount by the investment return on one
or more participating funds in a related mutual fund group. The Company
will consider your request, provided, among other things, that the
mutual fund group meets certain criteria established by the Company,
including diversification, liquidity, published valuation data, and
exchange privileges among the funds participating within the group. The
Company's decision as to whether it will follow your directed investment
request will be final and binding and it may actually invest in the
mutual fund, Interest on non-directed amounts will be credited in a
manner authorized by the Company.

You may make up to four requests in any calendar year to make changes in
the mutual fund group. If your directed investment request is approved
by the Company, you will assume full risk on the portion of your
deferred amounts subject to your request. The Company's approval of your
request should in no way be considered to be the Company's endorsement
of the particular mutual fund, the mutual fund group, or the
appropriateness of the investment decision. The Company in no way will
guarantee investment return. Investment return will be measured on a
"net" basis; that is, the gross investment return will be reduced by any
sales or redemption charges of any type imposed by the mutual fund.

In acknowledging acceptance of this Agreement, you specifically
acknowledge and agree that the Company will in no way be responsible for
the investment return on any directed Investment, that the Company in no
way guarantees any performance on any such amounts, that you will have
consulted with your personal financial or tax advisors and that the
Company is in no way responsible for financial or other consequences
resulting from any directed investment, and that the amount of the
Supplemental Retirement Benefit payable to you or your beneficiary under
this Agreement at the end of any deferral period will be directly
affected by the investment performance of any directed investment. You
further acknowledge and agree that the terms of this Agreement, and any
directed investment made by you, will be binding on you, your estate,
heirs, and beneficiaries, and you agree to indemnify and hold the
Company, its directors, officers and employees, harmless from any claims
or litigation.


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                                           Monsanto
                                           -----------------------------
                                           Monsanto Company
ROBERT L. BERRA                            800 N. Lindbergh Boulevard
Senior Vice President, Administration      St. Louis, Missouri 63167
                                           Phone: (314) 694-3756




                             June 12, 1989




Dr. Philip Needleman
Monsanto Company
800 North Lindbergh Boulevard
St. Louis, MC 63167

Dear Philip:

As you know, on February 1, 1989, you entered into an agreement
("Agreement") with the Company under which the Company awarded you,
subject to certain conditions, a Supplemental Retirement Benefit.

The Agreement provides that your Supplemental Retirement Benefit is
provided and continued at the sole discretion of the Executive
Compensation and Development Committee ("ECDC") and may be terminated in
whole or in part at any time for reasons such as, but not limited to,
your subsequent employment with a chemical, pharmaceutical or other
company in competition with Monsanto or your engaging in activities
deemed by the ECDC not to be in the best interests of Monsanto.

The ECDC has decided that in order to minimize any distractions that
could be caused by the personal uncertainties and risks created by a
change of control proposal, it is in the Company's best interest to
amend the Agreement by this addendum ("Addendum") to provide that upon a
Change of Control of the Company, your Supplemental Retirement Benefit
shall be fully vested and not subject to divestment for any reason by
the ECDC or its successor, the Board of Directors of Monsanto or
Monsanto's successor, or by any other person, committee, corporation or
other legal entity.  The term "Change of Control" has the same meaning
as it does in your Key Executive Employment Agreement.  This Addendum
incorporates the terms of the Agreement which shall remain in full force
and effect, except to the extent specifically modified hereby.



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On behalf of the Company, I am pleased to be able to inform you of this
Addendum authorized by the ECDC.  Please acknowledge your acceptance of
the terms of the Addendum by signing both copies of this letter and
returning one copy to me.

                                  Sincerely,

                                  MONSANTO COMPANY


                                  /s/ R.L. Berra
                                  ---------------------------------
                                  Senior Vice President


ACKNOWLEDGED AND AGREED:


/s/ Philip Needleman
--------------------------------
Philip Needleman, Ph.D.