<PAGE>
                                                                 EXHIBIT 10.1.1


                                    DELTAGEN, INC.
                                 AMENDED AND RESTATED
                              1998 STOCK INCENTIVE PLAN

                        (AS ADOPTED AND EFFECTIVE APRIL 30, 1998)


<PAGE>

                                  TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                  PAGE
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<S>                                                                               <C>
SECTION 1.  PURPOSE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1

SECTION 2.  DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (a)  "Award". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (b)  "Board of Directors" . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (c)  "Change in Control". . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (d)  "Code" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (e)  "Committee". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (f)  "Common-Law Employee". . . . . . . . . . . . . . . . . . . . . . . . . .  1
     (g)  "Company". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     (h)  "Employee" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     (i)  "Exchange Act" . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     (j)  "Exercise Price" . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     (k)  "Fair Market Value". . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     (l)  "Incentive Stock Option" or "ISO". . . . . . . . . . . . . . . . . . . .  3
     (m)  "Nonstatutory Option" or "NSO" . . . . . . . . . . . . . . . . . . . . .  3
     (n)  "Offeree". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (o)  "Option" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (p)  "Optionee" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (q)  "Outside Director" . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (r)  "Participant". . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (s)  "Plan" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     (t)  "Purchase Price" . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (u)  "Restricted Share" . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (v)  "Service". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (w)  "Share". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (x)  "Stock". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (y)  "Stock Award Agreement". . . . . . . . . . . . . . . . . . . . . . . . .  4
     (z)  "Stock Option Agreement" . . . . . . . . . . . . . . . . . . . . . . . .  4
     (aa)  "Stock Purchase Agreement". . . . . . . . . . . . . . . . . . . . . . .  4
     (ab)  "Subsidiary". . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4
     (ac)  "Total and Permanent Disability". . . . . . . . . . . . . . . . . . . .  4
     (ad)  "W-2 Payroll" . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4

SECTION 3.  ADMINISTRATION.. . . . . . . . . . . . . . . . . . . . . . . . . . . .  5
     (a)  Committee Membership.. . . . . . . . . . . . . . . . . . . . . . . . . .  5
     (b)  Committee Procedures.. . . . . . . . . . . . . . . . . . . . . . . . . .  5
     (c)  Committee Responsibilities.. . . . . . . . . . . . . . . . . . . . . . .  5
     (d)  Committee Liability. . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     (e)  Financial Reports. . . . . . . . . . . . . . . . . . . . . . . . . . . .  6

SECTION 4.  ELIGIBILITY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     (a)  General Rule.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6


                                      -i-
<PAGE>

     (b)  Ten-Percent Shareholders.. . . . . . . . . . . . . . . . . . . . . . . .  6
     (c)  Attribution Rules. . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     (d)  Outstanding Stock. . . . . . . . . . . . . . . . . . . . . . . . . . . .  7

SECTION 5.  STOCK SUBJECT TO PLAN. . . . . . . . . . . . . . . . . . . . . . . . .  7
     (a)  Basic Limitation.. . . . . . . . . . . . . . . . . . . . . . . . . . . .  7
     (b)  Additional Shares. . . . . . . . . . . . . . . . . . . . . . . . . . . .  7

SECTION 6.  TERMS AND CONDITIONS OF AWARDS OR SALES. . . . . . . . . . . . . . . .  7
     (a)  Stock Purchase Agreement.. . . . . . . . . . . . . . . . . . . . . . . .  7
     (b)  Duration of Offers.. . . . . . . . . . . . . . . . . . . . . . . . . . .  8
     (c)  Purchase Price.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .  8
     (d)  Payment for Shares.. . . . . . . . . . . . . . . . . . . . . . . . . . .  8
          (i)  Surrender of Stock. . . . . . . . . . . . . . . . . . . . . . . . .  8
          (ii)  Promissory Notes . . . . . . . . . . . . . . . . . . . . . . . . .  8
          (iii)  Cashless Exercise . . . . . . . . . . . . . . . . . . . . . . . .  9
          (iv)  Other Forms of Payment . . . . . . . . . . . . . . . . . . . . . .  9
     (e)  Exercise of Awards on Termination of Service . . . . . . . . . . . . . .  9

SECTION 7.  ADDITIONAL TERMS AND CONDITIONS OF RESTRICTED
       SHARES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
     (a)  Form and Amount of Award . . . . . . . . . . . . . . . . . . . . . . . .  9
     (b)  Exercisability . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
     (c)  Effect of Change in Control. . . . . . . . . . . . . . . . . . . . . . .  9
     (d)  Voting Rights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

SECTION 8.  TERMS AND CONDITIONS OF OPTIONS. . . . . . . . . . . . . . . . . . . . 10
     (a)  Stock Option Agreement.. . . . . . . . . . . . . . . . . . . . . . . . . 10
     (b)  Number of Shares.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     (c)  Exercise Price.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     (d)  Exercisability.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     (e)  Effect of Change in Control. . . . . . . . . . . . . . . . . . . . . . . 11
     (f)  Term.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
     (g)  Exercise of Options on Termination of Service. . . . . . . . . . . . . . 11
     (h)  Payment of Option Shares . . . . . . . . . . . . . . . . . . . . . . . . 11
          (i)  Surrender of Stock. . . . . . . . . . . . . . . . . . . . . . . . . 11
          (ii) Promissory Notes. . . . . . . . . . . . . . . . . . . . . . . . . . 12
          (iii) Cashless Exercise. . . . . . . . . . . . . . . . . . . . . . . . . 12
          (iv)  Other Forms of Payment . . . . . . . . . . . . . . . . . . . . . . 12
     (i)  No Rights as a Shareholder . . . . . . . . . . . . . . . . . . . . . . . 12
     (j)  Modification, Extension and Assumption of Options. . . . . . . . . . . . 12

SECTION 9.  ADJUSTMENT OF SHARES.. . . . . . . . . . . . . . . . . . . . . . . . . 12
     (a)  General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     (b)  Reorganizations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     (c)  Reservation of Rights. . . . . . . . . . . . . . . . . . . . . . . . . . 13


                                      -ii-
<PAGE>

SECTION 10.  WITHHOLDING TAXES . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     (a)  General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     (b)  Share Withholding. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     (c)  Cashless Exercise/Pledge . . . . . . . . . . . . . . . . . . . . . . . . 14
     (d)  Other Forms of Payment . . . . . . . . . . . . . . . . . . . . . . . . . 14

SECTION 11.  ASSIGNMENT OR TRANSFER OF AWARDS. . . . . . . . . . . . . . . . . . . 14
     (a)  General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     (b)  Trusts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

SECTION 12.  LEGAL REQUIREMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . 15

SECTION 13.  NO EMPLOYMENT RIGHTS. . . . . . . . . . . . . . . . . . . . . . . . . 15

SECTION 14.  DURATION AND AMENDMENTS.. . . . . . . . . . . . . . . . . . . . . . . 15
     (a)  Term of the Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
     (b)  Right to Amend or Terminate the Plan.. . . . . . . . . . . . . . . . . . 15
     (c)  Effect of Amendment or Termination.. . . . . . . . . . . . . . . . . . . 16

SECTION 15.  EXECUTION.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

FEDERAL TAX INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     Initial Grant of Options  . . . . . . . . . . . . . . . . . . . . . . . . . .  1
     Nonqualified Stock Options  . . . . . . . . . . . . . . . . . . . . . . . . .  1
     Incentive Stock Options   . . . . . . . . . . . . . . . . . . . . . . . . . .  2
     Alternative Minimum Tax . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
</TABLE>


                                      -iii-
<PAGE>

                                    DELTAGEN, INC.
                                 AMENDED AND RESTATED
                              1998 STOCK INCENTIVE PLAN

                        (AS ADOPTED AND EFFECTIVE APRIL 30, 1998)

SECTION 1.  PURPOSE.

     The purpose of the Plan is to offer selected employees, directors and
consultants an opportunity to acquire a proprietary interest in the success
of the Company, or to increase such interest, to encourage such selected
persons to remain in the employ of the Company and to attract new employees
with outstanding qualifications.  The Plan seeks to achieve this purpose by
providing for Awards in the form of Restricted Shares and Options (which may
constitute Incentive Stock Options or Nonstatutory Stock Options) as well as
the direct award or sale of Shares of the Company's Common Stock.  The Plan
was adopted by the Board on April 30, 1998.

SECTION 2.  DEFINITIONS.

     (a)  "AWARD" shall mean any award of an Option, Restricted Share or
other right under the Plan.

     (b)  "BOARD OF DIRECTORS" shall mean the Board of Directors of the
Company, as constituted from time to time.

     (c)  "CHANGE IN CONTROL" shall be defined by the Committee and provided
for in the Stock Purchase Agreements, Stock Option Agreements and Stock Award
Agreements.  The term "Change in Control" shall not include a transaction the
sole purpose of which is to change the state of the Company's incorporation.

     (d)  "CODE" shall mean the Internal Revenue Code of 1986, as amended.

     (e)  "COMMITTEE" shall mean a committee of the Board of Directors which
is authorized to administer the Plan under Section 3.

     (f)  "COMMON-LAW EMPLOYEE" means an individual paid from W-2 Payroll of
the Company or a Subsidiary.  If, during any period, the Company (or
Subsidiary, as applicable) has not treated an individual as a Common-Law
Employee and, for that reason, has not paid such individual in a manner which
results in the issuance of a Form W-2 and withheld taxes with respect to him
or her, then that individual shall not be an eligible


                                      -1-
<PAGE>

Employee for that period, even if any person, court of law or government
agency determines, retroactively, that that individual is or was a Common-Law
Employee during all or any portion of that period.

     (g)  "COMPANY" shall mean DELTAGEN, INC., a Delaware corporation.

     (h)  "EMPLOYEE" shall mean (i) any individual who is a Common-Law
Employee of the Company or of a Subsidiary, (ii) a member of the Board of
Directors, including (without limitation) an Outside Director, or an
affiliate of a member of the Board of Directors,(iii) a member of the board
of directors of a Subsidiary, or (iv) an independent contractor who performs
services for the Company or a Subsidiary.  Service as a member of the Board
of Directors, a member of the board of directors of a Subsidiary or an
independent contractor shall be considered employment for all purposes of the
Plan except the second sentence of Section 4(a).

     (i)  "EXCHANGE ACT" means the Securities and Exchange Act of 1934, as
amended.

     (j)  "EXERCISE PRICE" shall mean the amount for which one Share may be
purchased upon exercise of an Option, as specified by the Committee in the
applicable Stock Option Agreement.

     (k)  "FAIR MARKET VALUE" means the market price of Shares, determined by
the Committee as follows:

          (i) If the Shares were traded over-the-counter on the date in question
     but were not traded on the Nasdaq Stock Market or the Nasdaq National
     Market System, then the Fair Market Value shall be equal to the mean
     between the last reported representative bid and asked prices quoted for
     such date by the principal automated inter-dealer quotation system on which
     the Shares are quoted or, if the Shares are not quoted on any such system,
     by the "Pink Sheets" published by the National Quotation Bureau, Inc.;

          (ii) If the Shares were traded over-the-counter on the date in
     question and were traded on the Nasdaq Stock Market or the Nasdaq National
     Market System, then the Fair Market Value shall be equal to the
     last-transaction price quoted for such date by the Nasdaq Stock Market or
     the Nasdaq National Market;


                                      -2-
<PAGE>

          (iii) If the Shares were traded on a stock exchange on the date in
     question, then the Fair Market Value shall be equal to the closing price
     reported by the applicable composite transactions report for such date; and

          (iv) If none of the foregoing provisions is applicable, then the Fair
     Market Value shall be determined by the Committee in good faith on such
     basis as it deems appropriate.

     In all cases, the determination of Fair Market Value by the Committee
shall be conclusive and binding on all persons.

     (l)  "INCENTIVE STOCK OPTION" or "ISO" shall mean an employee incentive
stock option described in Code section 422(b).

     (m)  "NONSTATUTORY OPTION" or "NSO" shall mean an employee stock option
that is not an ISO.

     (n)  "OFFEREE" shall mean an individual to whom the Committee has
offered the right to acquire Shares under the Plan (other than upon exercise
of an Option).

     (o)  "OPTION" shall mean an Incentive Stock Option or Nonstatutory
Option granted under the Plan and entitling the holder to purchase Shares.

     (p)  "OPTIONEE" shall mean an individual or estate who holds an Option.

     (q)  "OUTSIDE DIRECTOR" shall mean a member of the Board who is not a
Common-Law Employee of the Company or a Subsidiary.

     (r)  "PARTICIPANT" shall means an individual or estate who holds an
Award.

     (s)  "PLAN" shall mean this DELTAGEN, INC., 1998 Stock Incentive Plan.

     (t)  "PURCHASE PRICE" shall mean the consideration for which one Share
may be acquired under the Plan (other than upon exercise of an Option), as
specified by the Committee.

     (u)  "RESTRICTED SHARE" shall mean a Share sold or granted to an
eligible Employee which is nontransferable and subject to substantial risk of
forfeiture until restrictions lapse.


                                      -3-
<PAGE>

     (v)  "SERVICE" shall mean service as an Employee.

     (w)  "SHARE" shall mean one share of Stock, as adjusted in accordance
with Section 9 (if applicable).

     (x)  "STOCK" shall mean the common stock of the Company.

     (y)  "STOCK AWARD AGREEMENT" shall mean the agreement between the
Company and the recipient of a Restricted Share which contains the terms,
conditions and restrictions pertaining to such Restricted Share.

     (z)  "STOCK OPTION AGREEMENT" shall mean the agreement between the
Company and an Optionee which contains the terms, conditions and restrictions
pertaining to his or her Option.

     (aa) "STOCK PURCHASE AGREEMENT" shall mean the agreement between the
Company and an Offeree who acquires Shares under the Plan which contains the
terms, conditions and restrictions pertaining to the acquisition of such
Shares.

     (bb) "SUBSIDIARY" means any corporation (other than the Company) in an
unbroken chain of corporations beginning with the Company, if each of the
corporations other than the last corporation in the unbroken chain owns stock
possessing 50% or more of the total combined voting power of all classes of
stock in one of the other corporations in such chain.  A corporation that
attains the status of a Subsidiary on a date after the adoption of the Plan
shall be considered a Subsidiary commencing as of such date.

     (cc) "TOTAL AND PERMANENT DISABILITY" means that the Optionee is unable
to engage in any substantial gainful activity by reason of any medically
determinable physical or mental impairment.

     (dd) "W-2 PAYROLL" means whatever mechanism or procedure that the
Company or a Subsidiary utilizes to pay any individual which results in the
issuance of Form W-2 to the individual.  "W-2 Payroll" does not include any
mechanism or procedure which results in the issuance of any form other than a
Form W-2 to an individual, including, but not limited to, any Form 1099 which
may be issued to an independent contractor, an agency employee or a
consultant.  Whether a mechanism or procedure qualifies as a "W-2 Payroll"
shall be determined in the absolute discretion of the Company (or Subsidiary,
as applicable), and the Company or Subsidiary determination shall be
conclusive and binding on all persons.


                                      -4-
<PAGE>

SECTION 3.  ADMINISTRATION.

     (a)  COMMITTEE MEMBERSHIP.  The Plan shall be administered by the
Committee appointed by the Board of Directors.  In the event the Company's
Shares become publicly traded, the Committee shall be comprised solely of two
or more Outside Directors (although Committee functions may be delegated to
officers to the extent the awards relate to persons who are not subject to
the reporting requirements of Section 16 of the Exchange Act).  If no
Committee has been appointed, the entire Board shall constitute the Committee.

     (b)  COMMITTEE PROCEDURES.  The Board of Directors shall designate one
of the members of the Committee as chairperson.  The Committee may hold
meetings at such times and places as it shall determine.  The acts of a
majority of the Committee members present at meetings at which a quorum
exists, or acts reduced to or approved in writing by all Committee members,
shall be valid acts of the Committee.

     (c)  COMMITTEE RESPONSIBILITIES.  The Committee has and may exercise
such power and authority as may be necessary or appropriate for the Committee
to carry out its functions as described in the Plan.  The Committee has
authority in its discretion to determine eligible Employees to whom, and the
time or times at which, Awards may be granted and the number of Shares
subject to each Award. Subject to the express provisions of the respective
Award agreements (which need not be identical) and to make all other
determinations necessary or advisable for Plan administration.  The Committee
has authority to prescribe, amend, and rescind rules and regulations relating
to the Plan.  All interpretations, determinations, and actions by the
Committee will be final, conclusive, and binding upon all persons.

     (d)  COMMITTEE LIABILITY.  No member of the Board or the Committee will
be liable for any action or determination made in good faith by the Committee
with respect to the Plan or any Award made under the Plan.

     (e)  FINANCIAL REPORTS.  To the extent required by applicable law, and
not less often than annually, the Company shall furnish to Offerees,
Optionees and Shareholders who have received Stock under the Plan its
financial statements including a balance sheet regarding the Company's
financial condition and results of operations, unless such Offerees,
Optionees or Shareholders have duties with the Company that assure them


                                      -5-
<PAGE>

access to equivalent information.  Such financial statements need not be
audited.

SECTION 4.  ELIGIBILITY.

     (a)  GENERAL RULE.  Only Employees, as defined in Section 2(h), shall be
eligible for designation as Participants by the Committee.  In addition, only
individuals who are employed as Common-Law Employees by the Company or a
Subsidiary shall be eligible for the grant of ISOs.

     (b)  TEN-PERCENT SHAREHOLDERS.  An Employee who owns more than ten
percent (10%) of the total combined voting power of all classes of
outstanding stock of the Company or any of its Subsidiaries shall not be
eligible for designation as an Offeree or Optionee unless (i) the Exercise
Price for an ISO (and a NSO to the extent required by applicable law) is at
least one hundred ten percent (110%) of the Fair Market Value of a Share on
the date of grant, (ii) the Purchase Price of Shares is at least one hundred
percent (100%) of the Fair Market Value of a Share on the date of grant, and
(iii) in the case of an ISO, such ISO by its terms is not exercisable after
the expiration of five years from the date of grant.

     (c)  ATTRIBUTION RULES.  For purposes of Subsection (b) above, in
determining stock ownership, an Employee shall be deemed to own the stock
owned, directly or indirectly, by or for his brothers, sisters, spouse,
ancestors and lineal descendants.  Stock owned, directly or indirectly, by or
for a corporation, partnership, estate or trust shall be deemed to be owned
proportionately by or for its shareholders, partners or beneficiaries.  Stock
with respect to which such Employee holds an Option shall not be counted.

     (d)  OUTSTANDING STOCK.  For purposes of Subsection (b) above,
"outstanding stock" shall include all stock actually issued and outstanding
immediately after the grant.  "Outstanding Stock" shall not include shares
authorized for issuance under outstanding Options held by the Employee or by
any other person.

SECTION 5.  STOCK SUBJECT TO PLAN.

     (a)  BASIC LIMITATION.  Shares offered under the Plan shall be
authorized but unissued Shares.  Subject to Sections 5(b) and 9 of the Plan,
the aggregate number of Shares which may be issued or transferred pursuant to
an Award under the Plan shall not exceed Three Million Seven Hundred
Fifty-Six Thousand Seven Hundred

                                      -6-
<PAGE>

Eighty Shares (3,756,780) In any event, (i) the number of Shares which are
subject to Awards or other rights outstanding at any time under the Plan
shall not exceed the number of Shares which then remain available for
issuance under the Plan; and (ii) the number of Shares which are subject to
Awards or other rights outstanding at any time under the Plan or otherwise
shall not exceed the limitation imposed by Section 260.140.45 of the Code of
Regulations of the California Commissioner of Corporations.  The Company,
during the term of the Plan, shall at all times reserve and keep available
sufficient Shares to satisfy the requirements of the Plan.

     (b)  ADDITIONAL SHARES.  In the event that any outstanding Option or other
right for any reason expires or is canceled or otherwise terminated, the Shares
allocable to the unexercised portion of such Option or other right shall again
be available for the purposes of the Plan.  If a Restricted Share is forfeited
before any dividends have been paid with respect to such Restricted Share, then
such Restricted Share shall again become available for award under the Plan.

SECTION 6.  TERMS AND CONDITIONS OF AWARDS OR SALES.

     (a)  STOCK PURCHASE AGREEMENT.  Each award or sale of Shares under the Plan
(other than upon exercise of an Option) shall be evidenced by a Stock Purchase
Agreement between the Offeree and the Company.  Such award or sale shall be
subject to all applicable terms and conditions of the Plan and may be subject to
any other terms and conditions which are not inconsistent with the Plan and
which the Committee deems appropriate for inclusion in a Stock Purchase
Agreement.  The provisions of the various Stock Purchase Agreements entered into
under the Plan need not be identical.


                                      -7-
<PAGE>


     (b)  DURATION OF OFFERS.  Any right to acquire Shares under the Plan (other
than an Option) shall automatically expire if not exercised by the Offeree
within 30 days after the grant of such right was communicated to the Offeree by
the Committee.

     (c)  PURCHASE PRICE.  The Purchase Price of Shares to be offered under the
Plan shall not be less than eighty-five percent (85%) of the Fair Market Value
of a Share on the date of grant (100% for 10% shareholders), except as otherwise
provided in Section 4(b).  Subject to the preceding sentence, the Purchase Price
shall be determined by the Committee in its sole discretion.  The Purchase Price
shall be payable in a form described in Subsection (d) below.

     (d)  PAYMENT FOR SHARES.  The entire Purchase Price of Shares issued under
the Plan shall be payable in lawful money of the United States of America at the
time when such Shares are purchased, except as provided below.  Notwithstanding
any other provision of the Plan, Shares may, in the discretion of the Committee,
be awarded under the Plan in consideration of Services rendered to the Company
or a Subsidiary prior to the Award.  Permissible forms of payment, in addition
to cash, are:

          (i) SURRENDER OF STOCK.  To the extent that a Purchase Option
     Agreement so provides, payment may be made all or in part with Shares which
     have already been owned by the Offeree or the Offeree's representative for
     any time period specified by the Committee and which are surrendered to the
     Company in good form for transfer.  Such Shares shall be valued at their
     Fair Market Value on the date when the new Shares are purchased under the
     Plan.

          (ii) PROMISSORY NOTES.  To the extent that a Stock Purchase Agreement
     so provides, payment may be made all or in part with a full recourse
     promissory note executed by the Offeree.  The interest rate and other terms
     and conditions of such note shall be determined by the Committee.  The
     Committee may require that the Offeree pledge his or her Shares to the
     Company for the purpose of securing the payment of such note.  In no event
     shall the stock certificate(s) representing such Shares be released to the
     Offeree until such note is paid in full.

          (iii) CASHLESS EXERCISE.  To the extent that a Stock Purchase
     Agreement so provides and a public market for the Shares exists, payment
     may be made all or in part by delivery (on a form prescribed by the
     Committee) of an irrevocable direction to a securities broker to sell


                                      -8-
<PAGE>


     Shares and to deliver all or part of the sale proceeds to the Company in
     payment of the aggregate Exercise Price.

          (iv) OTHER FORMS OF PAYMENT.  To the extent provided in the Stock
     Purchase Agreement, payment may be made in any other form that is
     consistent with applicable laws, regulations and rules, including payment
     for past services.

     (e)  EXERCISE OF AWARDS ON TERMINATION OF SERVICE.  Each Stock Award
Agreement shall set forth the extent to which the recipient shall have the right
to exercise the Award following termination of the recipient's Service with the
Company and its Subsidiaries.  Such provisions shall be determined in the sole
discretion of the Committee, need not be uniform among all the Awards issued
pursuant to the Plan, and may reflect distinctions based on the reasons for
termination of employment.

SECTION 7.  ADDITIONAL TERMS AND CONDITIONS OF RESTRICTED SHARES.

     (a)  FORM AND AMOUNT OF AWARD.  Each Stock Award Agreement shall specify
the number of Shares that are subject to the Award.  Restricted Shares may be
awarded in combination with NSOs and such an Award may provide that the
Restricted Shares will be forfeited in the event that the related NSOs are
exercised.

     (b)  EXERCISABILITY.  Each Stock Award Agreement shall specify the
conditions upon which Restricted Shares shall become vested, in full or in
installments. To the extent required by applicable law, a Stock Award shall
become exercisable no less rapidly than the rate of 20% per year for each of the
first five years from the date of grant.  Subject to the preceding sentence, the
exercisability of any Stock Award shall be determined by the Committee in its
sole discretion.

     (c)  EFFECT OF CHANGE IN CONTROL.  The Committee may determine at the time
of making an Award or thereafter, that such Award shall become fully vested in
the event that a Change in Control occurs with respect to the Company.

     (d)  VOTING RIGHTS.  Holders of Restricted Shares awarded under the Plan
shall have the same voting, dividend and other rights a the Company's other
stockholders.  A Stock Award Agreement, however, may require that the holders
invested any cash dividends received in additional Restricted Shares.  Such
additional Restricted Shares shall be subject to the same


                                      -9-
<PAGE>


conditions and restrictions as the Award with respect to which the dividends
were paid.  Such additional Restricted Shares shall not reduce the number of
Shares available under Section 5.

SECTION 8.  TERMS AND CONDITIONS OF OPTIONS.

     (a)  STOCK OPTION AGREEMENT.  Each grant of an Option under the Plan shall
be evidenced by a Stock Option Agreement between the Optionee and the Company.
Such Option shall be subject to all applicable terms and conditions of the Plan
and may be subject to any other terms and conditions which are not inconsistent
with the Plan and which the Committee deems appropriate for inclusion in a Stock
Option Agreement.  The provisions of the various Stock Option Agreements entered
into under the Plan need not be identical.

     (b)  NUMBER OF SHARES.  Each Stock Option Agreement shall specify the
number of Shares that are subject to the Option and shall provide for the
adjustment of such number in accordance with Section 9.  The Stock Option
Agreement shall also specify whether the Option is an ISO or a Nonstatutory
Option.

     (c)  EXERCISE PRICE.  Each Stock Option Agreement shall specify the
Exercise Price.  The Exercise Price of an ISO shall not be less than one hundred
percent (100%) of the Fair Market Value of a Share on the date of grant, except
as otherwise provided in Section 4(b).  To the extent required by applicable law
and except as otherwise provided in Section 4(b), the Exercise Price of a
Nonstatutory Option shall not be less than eighty-five percent (85%) of the Fair
Market Value of a Share on the date of grant.  Subject to the preceding two
sentences, the Exercise Price under any Option shall be determined by the
Committee in its sole discretion.  The Exercise Price shall be payable in a form
described in Subsection (h) below.

     (d)  EXERCISABILITY.  Each Stock Option Agreement shall specify the date
when all or any installment of the Option is to become exercisable.  To the
extent required by applicable law, an Option shall become exercisable no less
rapidly than the rate of 20% per year for each of the first five years from the
date of grant.  Subject to the preceding sentence, the exercisability of any
Option shall be determined by the Committee in its sole discretion.

     (e)  EFFECT OF CHANGE IN CONTROL.  The Committee may determine, at the time
of granting an Option or thereafter, that such Option shall become fully
exercisable as to all Shares subject to such Option in the event that a Change
in Control


                                     -10-
<PAGE>


occurs with respect to the Company.

     (f)  TERM.  The Stock Option Agreement shall specify the term of the
Option.  The term shall not exceed ten years from the date of grant (or five (5)
years for ten percent (10%) shareholders as provided in Section 4(b)).  Subject
to the preceding sentence, the Committee at its sole discretion shall determine
when an Option is to expire.

     (g)  EXERCISE OF OPTIONS ON TERMINATION OF SERVICE.  Each Option shall
set forth the extent to which the Optionee shall have the right to exercise
the Option following termination of the Optionee's Service with the Company
and its Subsidiaries.  Such provisions shall be determined in the sole
discretion of the Committee, need not be uniform among all Options issued
pursuant to the Plan, and may reflect distinctions based on the reasons for
termination of employment. Notwithstanding the foregoing, to the extent
required by applicable law, each Option shall provide that the Optionee shall
have the right to exercise the vested portion of any Option held at
termination for at least 30 days following termination of Service with the
Company for any reason, and that the Optionee shall have the right to
exercise the Option for at least six months if the Optionee's Service
terminates due to death or Disability.

     (h)  PAYMENT OF OPTION SHARES.  The entire Exercise Price of Shares issued
under the Plan shall be payable in lawful money of the United States of America
at the time when such Shares are purchased, except as provided below:

               (i) SURRENDER OF STOCK.  To the extent that a Stock Option
     Agreement so provides, payment may be made all or in part with Shares
     which have already been owned by the Optionee or the Optionee's
     representative for any time period specified by the Committee and
     which are surrendered to the Company in good form for transfer.  Such
     Shares shall be valued at their Fair Market Value on the date when the
     new Shares are purchased under the Plan.

               (ii) PROMISSORY NOTES.  To the extent that a Stock Option
     Agreement or Stock Purchase Agreement so provides, payment may be made
     all or in part with a full recourse promissory note executed by the
     Optionee or Offeree.  The interest rate and other terms and conditions
     of such note shall be determined by the Committee.  The Committee may
     require that the Optionee or Offeree pledge his or her Shares to the


                                      -11-
<PAGE>


     Company for the purpose of securing the payment of such note.  In no
     event shall the stock certificate(s) representing such Shares be
     released to the Optionee or Offeree until such note is paid in full.

               (iii)CASHLESS EXERCISE.  To the extent that a Stock Option
     Agreement so provides and a public market for the Shares exists,
     payment may be made all or in part by delivery (on a form prescribed
     by the Committee) of an irrevocable direction to a securities broker
     to sell Shares and to deliver all or part of the sale proceeds to the
     Company in payment of the aggregate Exercise Price.

               (iv) OTHER FORMS OF PAYMENT.  To the extent provided in the
     Stock Option Agreement, payment may be made in any other form that is
     consistent with applicable laws, regulations and rules.

     (i)  NO RIGHTS AS A SHAREHOLDER.  An Optionee, or a transferee of an
Optionee, shall have no rights as a shareholder with respect to any Shares
covered by an Option until the date of the issuance of a stock certificate for
such Shares.

     (j)  MODIFICATION, EXTENSION AND ASSUMPTION OF OPTIONS.  Within the
limitations of the Plan, the Committee may modify, extend or assume outstanding
Options or may accept the cancellation of outstanding Options (whether granted
by the Company or another issuer) in return for the grant of new Options for the
same or a different number of Shares and at the same or a different Exercise
Price or for other consideration.

SECTION 9.  ADJUSTMENT OF SHARES.

     (a)  GENERAL.  In the event of a subdivision of the outstanding Stock, a
declaration of a dividend payable in Shares, a declaration of a dividend payable
in a form other than Shares in an amount that has a material effect on the value
of Shares, a combination or consolidation of the outstanding Stock into a lesser
number of Shares, a recapitalization, a reclassification or a similar
occurrence, the Committee shall make appropriate adjustments in one or more of
(i) the number of Shares available for future Awards under Section 5, (ii) the
number of Shares covered by each outstanding Option or Purchase Agreement or
(iii) the Exercise Price or Purchase Price under each outstanding Option or
Stock Purchase Agreement.


                                      -12-
<PAGE>


     (b)  REORGANIZATIONS.  In the event that the Company is a party to a merger
or reorganization, outstanding Options shall be subject to the agreement of
merger or reorganization.

     (c)  RESERVATION OF RIGHTS.  Except as provided in this Section 9, an
Optionee or an Offeree shall have no rights by reason of (i) any subdivision or
consolidation of shares of stock of any class, (ii) the payment of any dividend
or (iii) any other increase or decrease in the number of shares of stock of any
class.  Any issue by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall not affect, and no
adjustment by reason thereof shall be made with respect to, the number, Exercise
Price or Purchase Agreement of Shares subject to an Option or Stock Purchase
Agreement.  The grant of an Award pursuant to the Plan shall not affect in any
way the right or power of the Company to make adjustments, reclassifications,
reorganizations or changes of its capital or business structure, to merge or
consolidate or to dissolve, liquidate, sell or transfer all or any part of its
business or assets.

SECTION 10.  WITHHOLDING TAXES.

     (a)  GENERAL.  To the extent required by applicable federal, state, local
or foreign law, a Participant or his or her successor shall make arrangements
satisfactory to the Committee for the satisfaction of any withholding tax
obligations that arise in connection with the Plan.  The Company shall not be
required to issue any Shares or make any cash payment under the Plan until such
obligations are satisfied.

     (b)  SHARE WITHHOLDING.  The Committee may permit a Participant to satisfy
all or part of his or her withholding or income tax obligations by having the
Company withhold all or a portion of any Shares that otherwise would be issued
to him or her or by surrendering all or a portion of any Shares that he or she
previously acquired.  Such Shares shall be valued at their Fair Market Value on
the date when taxes otherwise would be withheld in cash.  Any payment of taxes
by assigning Shares to the Company may be subject to restrictions, including any
restrictions required by rules of any federal or state regulatory body or other
authority.

     (c)  CASHLESS EXERCISE/PLEDGE.  The Committee may provide that if Company
Shares are publicly traded at the time of exercise, arrangements may be made to
meet the Optionee's withholding obligation by cashless exercise or pledge.


                                      -13-
<PAGE>


     (d)  OTHER FORMS OF PAYMENT.  The Committee may permit such other means of
tax withholding as it deems appropriate.

SECTION 11.  ASSIGNMENT OR TRANSFER OF AWARDS.

     (a)  GENERAL.  An Award granted under the Plan shall not be anticipated,
assigned, attached, garnished, optioned, transferred or made subject to any
creditor's process, whether voluntarily, involuntarily or by operation of law,
except as approved by the Committee.  Notwithstanding the foregoing, ISOs may
not be transferable.  Also notwithstanding the foregoing, while the Shares are
subject to California Corporations Code Section 25102(o), Offerees and Optionees
may not transfer their rights hereunder except by will, beneficiary designation
or the laws of descent and distribution, and (ii) any rights of repurchase in
favor of the Company shall take into account the provisions of Department of
Corporations Regulation Section 260.140.41 or 260.140.42, as applicable.

     (b)  TRUSTS.  Neither this Section 11 nor any other provision of the Plan
shall preclude a Participant from transferring or assigning Restricted Shares to
(a) the trustee of a trust that is revocable by such Participant alone, both at
the time of the transfer or assignment and at all times thereafter prior to such
Participant's death, or (b) the trustee of any other trust to the extent
approved by the Committee in writing.  A transfer or assignment of Restricted
Shares from such trustee to any other person than such Participant shall be
permitted only to the extent approved in advance by the Committee in writing,
and Restricted Shares held by such trustee shall be subject to all the
conditions and restrictions set forth in the Plan and in the applicable Stock
Award Agreement, as if such trustee were a party to such Agreement.

SECTION 12.  LEGAL REQUIREMENTS.

     Shares shall not be issued under the Plan unless the issuance and delivery
of such Shares complies with (or is exempt from) all applicable requirements of
law, including (without limitation) the Securities Act of 1933, as amended, the
rules and regulations promulgated thereunder, state securities laws and
regulations, and the regulations of any stock exchange on which the Company's
securities may then be listed.

SECTION 13.  NO EMPLOYMENT RIGHTS.

     No provision of the Plan, nor any right or Option granted


                                      -14-
<PAGE>


under the Plan, shall be construed to give any person any right to become, to
be treated as, or to remain an Employee.  The Company and its Subsidiaries
reserve the right to terminate any person's Service at any time and for any
reason.

SECTION 14.  DURATION AND AMENDMENTS.

     (a)  TERM OF THE PLAN.  The Plan, as set forth herein, shall become
effective on the date of its adoption by the Board of Directors, subject to the
approval of the Company's shareholders.  In the event that the shareholders fail
to approve the Plan within twelve (12) months after its adoption by the Board of
Directors, any grants already made shall be null and void, and no additional
grants shall be made after such date.  The Plan shall terminate automatically
ten (10) years after its adoption by the Board of Directors and may be
terminated on any earlier date pursuant to Subsection (b) below.

     (b)  RIGHT TO AMEND OR TERMINATE THE PLAN.  The Board of Directors may
amend the Plan at any time and from time to time.  Rights and obligations under
any right or Option granted before amendment of the Plan shall not be materially
altered, or impaired adversely, by such amendment, except with consent of the
person to whom the right or Option was granted.  An amendment of the Plan shall
be subject to the approval of the Company's shareholders only to the extent
required by applicable laws, regulations or rules including the rules of any
applicable exchange.

     (c)  EFFECT OF AMENDMENT OR TERMINATION.  No Shares shall be issued or sold
under the Plan after the termination thereof, except upon exercise of an Option
granted prior to such termination.  The termination of the Plan, or any
amendment thereof, shall not affect any Shares previously issued or any Option
previously granted under the Plan.

SECTION 15.  EXECUTION.

     To record the adoption of the Plan by the Company effective as of April
30, 1998 and its amendment as of July 17, 1998, September 16, 1999, December
16, 1999, January 21, 2000 and April 5, 2000, the Board of Directors
has caused its authorized officer to execute the same this 11th day of April,
2000.


                                 DELTAGEN, INC.



                          By  /s/ William Matthews, Ph.D.
                              ----------------------------
                              William Matthews, Ph.D.
                              President and Chief
                                Executive Officer


                                      15