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                                                                    EXHIBIT 10.3

                                  DELTAGEN, INC

                        2000 EMPLOYEE STOCK PURCHASE PLAN

                     (Adopted by the Board on April 9, 2000)

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                                TABLE OF CONTENTS

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SECTION 1 Purpose Of The Plan..................................................1

SECTION 2 Definitions..........................................................1
      (a) "Accumulation Period"................................................1
      (b) "Board"..............................................................1
      (c) "Code"...............................................................1
      (d) "Committee"..........................................................1
      (e) "Company"............................................................1
      (f) "Compensation".......................................................1
      (g) "Corporate Reorganization"...........................................2
      (h) "Eligible Employee"..................................................2
      (i) "Exchange Act".......................................................2
      (j) "Fair Market Value"..................................................2
      (k) "IPO"................................................................2
      (l) "Offering Period"....................................................3
      (m) "Participant"........................................................3
      (n) "Participating Company"..............................................3
      (o) "Plan"...............................................................3
      (p) "Plan Account".......................................................3
      (q) "Purchase Price".....................................................3
      (r) "Stock"..............................................................3
      (s) "Subsidiary".........................................................3

SECTION 3 Administration Of The Plan...........................................3
      (a) Committee Composition................................................3
      (b) Committee Responsibilities...........................................4

SECTION 4 Enrollment And Participation.........................................4
      (a) Offering Periods.....................................................4
      (b) Accumulation Periods.................................................4
      (c) Enrollment...........................................................4
      (d) Duration of Participation............................................4
      (e) Applicable Offering Period...........................................4

SECTION 5 Employee Contributions...............................................5
      (a) Frequency of Payroll Deductions......................................5
      (b) Amount of Payroll Deductions.........................................5
      (c) Changing Withholding Rate............................................5
      (d) Discontinuing Payroll Deductions.....................................5
      (e) Limit on Number of Elections.........................................6

SECTION 6 Withdrawal From The Plan.............................................6
      (a) Withdrawal...........................................................6
      (b) Re-enrollment After Withdrawal.......................................6

SECTION 7 Change In Employment Status..........................................6
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      (a) Termination of Employment............................................6
      (b) Leave of Absence.....................................................6
      (c) Death................................................................6

SECTION 8 Plan Accounts And Purchase Of Shares.................................7
      (a) Plan Accounts........................................................7
      (b) Purchase Price.......................................................7
      (c) Number of Shares Purchased...........................................7
      (d) Available Shares Insufficient........................................7
      (e) Issuance of Stock....................................................7
      (f) Unused Cash Balances.................................................8
      (g) Stockholder Approval.................................................8

SECTION 9 Limitations On Stock Ownership.......................................8
      (a) Five Percent Limit...................................................8
      (b) Dollar Limit.........................................................8

SECTION 10 Rights Not Transferable.............................................9

SECTION 11 No Rights As An Employee............................................9

SECTION 12 No Rights As A Stockholder..........................................9

SECTION 13 Securities Law Requirements.........................................9

SECTION 14 Stock Offered Under The Plan........................................9
      (a) Authorized Shares....................................................9
      (b) Antidilution Adjustments............................................10
      (c) Reorganizations.....................................................10

SECTION 15 Amendment Or Discontinuance........................................10

SECTION 16 Execution..........................................................11
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                                 DELTAGEN, INC.

                        2000 EMPLOYEE STOCK PURCHASE PLAN

SECTION 1         PURPOSE OF THE PLAN.

         The Plan was adopted by the Board on April 9, 2000, effective as of
the date of the IPO. The purpose of the Plan is to provide Eligible Employees
with an opportunity to increase their proprietary interest in the success of the
Company by purchasing Stock from the Company on favorable terms and to pay for
such purchases through payroll deductions. The Plan is intended to qualify under
section 423 of the Code.

SECTION 2         DEFINITIONS.

         (a)      "ACCUMULATION PERIOD" means a six-month period during which
contributions may be made toward the purchase of Stock under the Plan, as
determined pursuant to Section 4(b).

         (b)      "BOARD" means the Board of Directors of the Company, as
constituted from time to time.

         (c)      "CODE" means the Internal Revenue Code of 1986, as amended.

         (d)      "COMMITTEE" means a committee of the Board, as described in
Section 3.

         (e)      "COMPANY" means Deltagen, Inc., a Delaware Corporation.

         (f)      "COMPENSATION" means (i) the total compensation paid in cash
to a Participant by a Participating Company, including salaries, wages, bonuses,
incentive compensation, commissions, overtime pay and shift premiums, plus (ii)
any pre-tax contributions made by the Participant under section 401(k) or 125 of
the Code. "Compensation" shall exclude all non-cash items, moving or relocation
allowances, cost-of-living equalization payments, car allowances, tuition
reimbursements, imputed income attributable to cars or life insurance, severance
pay, fringe benefits, contributions or benefits received under employee benefit
plans, income attributable to the exercise of stock options, and similar items.
The Committee shall determine whether a particular item is included in
Compensation.

         (g)      "CORPORATE REORGANIZATION" means:

                  (i)      The consummation of a merger or consolidation of the
Company with or into another entity, or any other corporate reorganization; or

                  (ii)     The sale, transfer or other disposition of all or
substantially all of the Company's assets or the complete liquidation or
dissolution of the Company.


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         (h)      "ELIGIBLE EMPLOYEE" means any employee of a Participating
Company whose customary employment is for more than five months per calendar
year and for more than 20 hours per week.

         The foregoing notwithstanding, an individual shall not be considered an
Eligible Employee if his or her participation in the Plan is prohibited by the
law of any country which has jurisdiction over him or her or if he or she is
subject to a collective bargaining agreement that does not provide for
participation in the Plan.

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

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

                  (i)      If Stock was traded on The Nasdaq National Market on
         the date in question, then the Fair Market Value shall be equal to the
         last-transaction price quoted for such date by The Nasdaq National
         Market;

                  (ii)     If Stock was 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; or

                  (iii)    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.

         Whenever possible, the determination of Fair Market Value by the
Committee shall be based on the prices reported in the WALL STREET JOURNAL or as
reported directly to the Company by Nasdaq or a stock exchange. Such
determination shall be conclusive and binding on all persons.

         (k)      "IPO" means the initial offering of Stock to the public
pursuant to a registration statement filed by the Company with the Securities
and Exchange Commission.

         (l)      "OFFERING PERIOD" means a 12- or 24-month period with
respect to which the right to purchase Stock may be granted under the Plan,
as determined pursuant to Section 4(a).

         (m)      "PARTICIPANT" means an Eligible Employee who elects to
participate in the Plan, as provided in Section 4(c).

         (n)      "PARTICIPATING COMPANY" means (i) the Company and (ii) each
present or future Subsidiary designated by the Committee as a Participating
Company.

         (o)      "PLAN" means this Deltagen, Inc. 2000 Employee Stock Purchase
Plan, as it may be amended from time to time.

         (p)      "PLAN ACCOUNT" means the account established for each
Participant pursuant to Section 8(a).


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         (q)      "PURCHASE PRICE" means the price at which Participants may
purchase Stock under the Plan, as determined pursuant to Section 8(b).

         (r)      "STOCK" means the Common Stock of the Company.

         (s)      "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.

SECTION 3         ADMINISTRATION OF THE PLAN.

         (a)      COMMITTEE COMPOSITION. The Plan shall be administered by the
Committee. The Committee shall consist exclusively of one or more directors of
the Company, who shall be appointed by the Board.

         (b)      COMMITTEE RESPONSIBILITIES. The Committee shall interpret the
Plan and make all other policy decisions relating to the operation of the Plan.
The Committee may adopt such rules, guidelines and forms as it deems appropriate
to implement the Plan. The Committee's determinations under the Plan shall be
final and binding on all persons.

SECTION 4         ENROLLMENT AND PARTICIPATION.

         (a)      OFFERING PERIODS. While the Plan is in effect, two Offering
Periods shall commence in each calendar year. The Offering Periods shall consist
of the 24-month periods commencing on each January 1 and July 1, except that the
first Offering Period shall consist of a 12-month period commencing on the
date of the IPO and ending on June 30, 2001.

         (b)      ACCUMULATION PERIODS. While the Plan is in effect, two
Accumulation Periods shall commence in each calendar year. The Accumulation
Periods shall consist of the six month periods commencing on January 1 and July
1, except that the first Accumulation Period shall commence on the date of the
IPO and end on December 31, 2000.

         (c)      ENROLLMENT. Any individual who, on the day preceding the
first day of an Offering Period (other than the initial Offering Period),
qualifies as an Eligible Employee may elect to become a Participant in the
Plan for such Offering Period by executing the enrollment form prescribed for
this purpose by the Committee. The enrollment form shall be filed with the
Company at the prescribed location not later than 15 days prior to the
commencement of such Offering Period. All Eligible Employees shall be
automatically enrolled in the initial Offering Period under the Plan.

         (d)      DURATION OF PARTICIPATION. Once enrolled in the Plan, a
Participant shall continue to participate in the Plan until he or she ceases to
be an Eligible Employee, withdraws from the Plan under Section 5(a) or reaches
the end of the Offering Period in which his or her employee contributions were
discontinued under Section 5(d) or 9(b). A Participant who discontinued employee
contributions under Section 5(d) or 9(b) or withdrew from the Plan under Section
6(a) may again become a Participant, if he or she then is an Eligible Employee,
by following the procedure described in Subsection (c) above. A Participant
whose employee contributions were discontinued automatically under Section 9(b)
shall automatically resume participation at the


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beginning of the earliest Offering Period ending in the next calendar year, if
he or she then is an Eligible Employee.

         (e)      APPLICABLE OFFERING PERIOD. For purposes of calculating the
purchase price under Section 8(b), the applicable Offering Period shall be
determined as follows:

                  (i)      Once a Participant is enrolled in the Plan for an
         Offering Period, such Offering Period shall continue to apply to him or
         her until the earliest of: (A) the end of such Offering Period; (B) the
         end of his or her participation under Subsection (d) above; or (C)
         re-enrollment in a subsequent Offering Period under Paragraph (ii)
         below.

                  (ii)     In the event that the Fair Market Value of Stock on
         the last trading day before the commencement of the Offering Period in
         which the Participant is enrolled is higher than on the last trading
         day before the commencement of any subsequent Offering Period, the
         Participant shall automatically be re-enrolled for such subsequent
         Offering Period.

                  (iii)    When a Participant reaches the end of an Offering
         Period but his or her participation is to continue, then such
         Participant shall automatically be re-enrolled for the Offering Period
         that commences immediately after the end of the prior Offering Period.

SECTION 5         EMPLOYEE CONTRIBUTIONS.

         (a)      FREQUENCY OF PAYROLL DEDUCTIONS. A Participant may purchase
shares of Stock under the Plan solely by means of payroll deductions;
provided, however, that in the initial Accumulation Period, Participants may
also purchase shares of Stock by making a lump sum cash payment at the end of
the Accumulation Period. Payroll deductions, as designated by the Participant
pursuant to Subsection (b) below, shall occur on each payday during
participation in the Plan.

         (b)      AMOUNT OF PAYROLL DEDUCTIONS. An Eligible Employee shall
designate on the enrollment form the portion of his or her Compensation that
he or she elects to have withheld for the purchase of Stock. Such portion
shall be a whole percentage of the Eligible Employee's Compensation, but not
less than 1% nor more than 15%. During the initial Accumulation Period, no
payroll deduction will be made unless a Participant files a supplemental
enrollment form within 15 days after written notice to Participants of the
effectiveness of a registration statement covering the Stock and filed under
the Securities Act of 1933, as amended.

         (c)      CHANGING WITHHOLDING RATE. If a Participant wishes to change
the rate of payroll withholding, he or she may do so by filing a new enrollment
form with the Company at the prescribed location at any time. The new
withholding rate shall be effective as soon as reasonably practicable after such
form has been received by the Company. The new withholding rate shall be a whole
percentage of the Eligible Employee's Compensation, but not less than 1% nor
more than 15%.

         (d)      DISCONTINUING PAYROLL DEDUCTIONS. If a Participant wishes to
discontinue employee contributions entirely, he or she may do so by filing a new
enrollment form with the Company at the prescribed location at any time. Payroll
withholding shall cease as soon as reasonably practicable after such form has
been received by the Company. In addition, employee contributions may be
discontinued automatically pursuant to Section 9(b). A Participant who has
discontinued employee contributions may resume such contributions by filing a
new enrollment form with the Company at the prescribed location. Payroll
withholding


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shall resume as soon as reasonably practicable after such form has been received
by the Company.

         (e)      LIMIT ON NUMBER OF ELECTIONS. No Participant shall make
more than four elections under Subsection (c) or (d) above during any
Calendar Year.

SECTION 6         WITHDRAWAL FROM THE PLAN.

         (a)      WITHDRAWAL. A Participant may elect to withdraw from the
Plan by filing the prescribed form with the Company at the prescribed
location at any time before the last day of an Accumulation Period; provided,
however, that in the initial Accumulation Period, Participants may be deemed
to withdraw from the Plan by declining or failing to send timely payment for
the shares of Stock. As soon as reasonably practicable thereafter, payroll
deductions shall cease and the entire amount credited to the Participant's
Plan Account shall be refunded to him or her in cash, without interest. No
partial withdrawals shall be permitted.

         (b)      RE-ENROLLMENT AFTER WITHDRAWAL. A former Participant who has
withdrawn from the Plan shall not be a Participant until he or she re-enrolls in
the Plan under Section 4(c). Re-enrollment may be effective only at the
commencement of an Offering Period.

SECTION 7         CHANGE IN EMPLOYMENT STATUS.

         (a)      TERMINATION OF EMPLOYMENT. Termination of employment as an
Eligible Employee for any reason, including death, shall be treated as an
automatic withdrawal from the Plan under Section 6(a). Notwithstanding the
foregoing in this Section 7, a transfer from one Participating Company to
another shall not be treated as a termination of employment.

         (b)      LEAVE OF ABSENCE. For purposes of the Plan, employment shall
not be deemed to terminate when the Participant goes on a military leave, a
sick leave or another bona fide leave of absence, if the leave was approved
by the Company in writing. Employment, however, shall be deemed to terminate
90 days after the Participant goes on a leave, unless a contract or statute
guarantees his or her right to return to work. Employment shall be deemed to
terminate in any event when the approved leave ends, unless the Participant
immediately returns to work.

         (c)      DEATH. In the event of the Participant's death, the amount
credited to his or her Plan Account shall be paid to a beneficiary designated
by him or her for this purpose on the prescribed form or, if none, to the
Participant's estate. Such form shall be valid only if it was filed with the
Company at the prescribed location before the Participant's death.

SECTION 8         PLAN ACCOUNTS AND PURCHASE OF SHARES.

         (a)      PLAN ACCOUNTS. The Company shall maintain a Plan Account on
its books in the name of each Participant. Whenever an amount is deducted
from the Participant's Compensation under the Plan, such amount shall be
credited to the Participant's Plan Account. Amounts credited to Plan Accounts
shall not be trust funds and may be commingled with the Company's general
assets and applied to general corporate purposes. No interest shall be
credited to Plan Accounts.

         (b)      PURCHASE PRICE. The Purchase Price for each share of Stock
purchased at the close of an Accumulation Period shall be the lower of:


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                  (i)      85% of the Fair Market Value of such share on the
         last trading day in such Accumulation Period; or

                  (ii)     85% of the Fair Market Value of such share on the
         last trading day before the commencement of the applicable Offering
         Period (as determined under Section 4(e)) or, in the case of the first
         Offering Period under the Plan, 85% of the price at which one share of
         Stock is offered to the public in the IPO.

         (c)      NUMBER OF SHARES PURCHASED. As of the last day of each
Accumulation Period, each Participant shall be deemed to have elected to
purchase the number of shares of Stock calculated in accordance with this
Subsection (c), unless the Participant has previously elected to withdraw
from the Plan in accordance with Section 6(a) or unless a Participant is
deemed to have withdrawn from the Plan pursuant to Section 6(a). The amount
then in the Participant's Plan Account shall be divided by the Purchase
Price, and the number of shares that results shall be purchased from the
Company with the funds in the Participant's Plan Account. The foregoing
notwithstanding, no Participant shall purchase more than 1,200 shares of
Stock with respect to any Accumulation Period nor more than the amounts of
Stock set forth in Sections 9(b) and 14(a). The Committee may determine with
respect to all Participants that any fractional share, as calculated under
this Subsection (c), shall be (i) rounded down to the next lower whole share
or (ii) credited as a fractional share.

         (d)      AVAILABLE SHARES INSUFFICIENT. In the event that the aggregate
number of shares that all Participants elect to purchase during an Accumulation
Period exceeds the maximum number of shares remaining available for issuance
under Section 14(a), then the number of shares to which each Participant is
entitled shall be determined by multiplying the number of shares available for
issuance by a fraction, the numerator of which is the number of shares that such
Participant has elected to purchase and the denominator of which is the number
of shares that all Participants have elected to purchase.

         (e)      ISSUANCE OF STOCK. Certificates representing the shares of
Stock purchased by a Participant under the Plan shall be issued to him or her as
soon as reasonably practicable after the close of the applicable Accumulation
Period, except that the Committee may determine that such shares shall be held
for each Participant's benefit by a broker designated by the Committee (unless
the Participant has elected that certificates be issued to him or her). Shares
may be registered in the name of the Participant or jointly in the name of the
Participant and his or her spouse as joint tenants with right of survivorship or
as community property.

         (f)      UNUSED CASH BALANCES. An amount remaining in the Participant's
Plan Account that represents the Purchase Price for any fractional share shall
be carried over in the Participant's Plan Account to the next Accumulation
Period. Any amount remaining in the Participant's Plan Account that represents
the Purchase Price for whole shares that could not be purchased by reason of
Subsection (c) above, Section 9(b) or Section 14(a) shall be refunded to the
Participant in cash, without interest.

         (g)      STOCKHOLDER APPROVAL. Any other provision of the Plan
notwithstanding, no shares of Stock shall be purchased under the Plan unless and
until the Company's stockholders have approved the adoption of the Plan.


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SECTION 9         LIMITATIONS ON STOCK OWNERSHIP.

         (a)      FIVE PERCENT LIMIT. Any other provision of the Plan
notwithstanding, no Participant shall be granted a right to purchase Stock under
the Plan if such Participant, immediately after his or her election to purchase
such Stock, would own stock possessing more than 5% of the total combined voting
power or value of all classes of stock of the Company or any parent or
Subsidiary of the Company. For purposes of this Subsection (a), the following
rules shall apply:

                  (i)      Ownership of stock shall be determined after applying
         the attribution rules of section 424(d) of the Code;

                  (ii)     Each Participant shall be deemed to own any stock
         that he or she has a right or option to purchase under this or any
         other plan; and

                  (iii)    Each Participant shall be deemed to have the right to
         purchase 1,200 shares of Stock under this Plan with respect to each
         Accumulation Period.

         (b)      DOLLAR LIMIT. Any other provision of the Plan notwithstanding,
no Participant shall purchase Stock with a Fair Market Value in excess of the
following limit:

         Any other provision of the Plan notwithstanding, no Participant shall
purchase Stock with a Fair Market Value in excess of $25,000 per calendar year
(under this Plan and all other employee stock purchase plans of the Company or
any parent or Subsidiary of the Company).

         For purposes of this Subsection (b), the Fair Market Value of Stock
shall be determined in each case as of the beginning of the Offering Period in
which such Stock is purchased. Employee stock purchase plans not described in
section 423 of the Code shall be disregarded. If a Participant is precluded by
this Subsection (b) from purchasing additional Stock under the Plan, then his or
her employee contributions shall automatically be discontinued and shall resume
at the beginning of the earliest Accumulation Period ending in the next calendar
year (if he or she then is an Eligible Employee).

SECTION 10        RIGHTS NOT TRANSFERABLE.

         The rights of any Participant under the Plan, or any Participant's
interest in any Stock or moneys to which he or she may be entitled under the
Plan, shall not be transferable by voluntary or involuntary assignment or by
operation of law, or in any other manner other than by beneficiary designation
or the laws of descent and distribution. If a Participant in any manner attempts
to transfer, assign or otherwise encumber his or her rights or interest under
the Plan, other than by beneficiary designation or the laws of descent and
distribution, then such act shall be treated as an election by the Participant
to withdraw from the Plan under Section 6(a).

SECTION 11        NO RIGHTS AS AN EMPLOYEE

         Nothing in the Plan or in any right granted under the Plan shall confer
upon the Participant any right to continue in the employ of a Participating
Company for any period of specific duration or interfere with or otherwise
restrict in any way the rights of the Participating


                                      -7-
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Companies or of the Participant, which rights are hereby expressly reserved by
each, to terminate his or her employment at any time and for any reason, with or
without cause.

SECTION 12        NO RIGHTS AS A STOCKHOLDER.

         A Participant shall have no rights as a stockholder with respect to any
shares of Stock that he or she may have a right to purchase under the Plan until
such shares have been purchased on the last day of the applicable Offering
Period.

SECTION 13        SECURITIES LAW REQUIREMENTS.

         Shares of Stock shall not be issued under the Plan unless the issuance
and delivery of such shares comply with (or are 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 or other
securities market on which the Company's securities may then be traded.

SECTION 14        STOCK OFFERED UNDER THE PLAN.

         (a)      AUTHORIZED SHARES. The maximum aggregate number of shares
of Stock available for purchase under the Plan is one million (1,000,000),
plus an annual increase to be added on the first day of the Company's fiscal
year beginning in 2001 equal to the lesser of (i) 5% of the fully diluted
outstanding shares of Common Stock of the Company on such date or (ii) a
lesser amount determined by the Board. The aggregate number of Shares
available for purchase under the Plan shall at all times be subject to
adjustment pursuant to Section 14.

         (b)      ANTIDILUTION ADJUSTMENTS. The aggregate number of shares of
Stock offered under the Plan, the 1,200 share limitation described in Section
8(c) and the price of shares that any Participant has elected to purchase shall
be adjusted proportionately by the Committee for any increase or decrease in the
number of outstanding shares of Stock resulting from a subdivision or
consolidation of shares or the payment of a stock dividend, any other increase
or decrease in such shares effected without receipt or payment of consideration
by the Company, the distribution of the shares of a Subsidiary to the Company's
stockholders or a similar event.

         (c)      REORGANIZATIONS. Any other provision of the Plan
notwithstanding, immediately prior to the effective time of a Corporate
Reorganization, the Offering Period then in progress shall terminate and shares
shall be purchased pursuant to Section 8, unless the Plan is assumed by the
surviving corporation or its parent corporation pursuant to the plan of merger
or consolidation. The Plan shall in no event be construed to restrict in any way
the Company's right to undertake a dissolution, liquidation, merger,
consolidation or other reorganization.

SECTION 15        AMENDMENT OR DISCONTINUANCE.

         The Board shall have the right to amend, suspend or terminate the Plan
at any time and without notice. Except as provided in Section 14, any increase
in the aggregate number of shares of Stock to be issued under the Plan shall be
subject to approval by a vote of the stockholders of the Company. In addition,
any other amendment of the Plan shall be subject to approval by a


                                      -8-
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vote of the stockholders of the Company to the extent required by an applicable
law or regulation.

SECTION 16        EXECUTION.

         To record the adoption of the Plan by the Board on April 9, 2000, the
Company has caused its authorized officer to execute the same.



                         Deltagen, Inc.

                         By: /s/ William Matthews, Ph.D.
                            ---------------------------------------------------

                         Title: President and Chief Executive Officer
                               ------------------------------------------------


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