Exhibit 10.1

                             APPLERA CORPORATION

                         PERFORMANCE UNIT BONUS PLAN

                    (as amended through August 16, 2001)

1.    Purpose of the Plan.

      The purpose of the Applera Corporation Performance Unit Bonus Plan (the
"Plan") is to increase stockholder value and to advance the interests of
Applera Corporation and its subsidiaries (collectively, the "Corporation") by
providing financial incentives designed to attract, retain, and motivate key
employees of the Corporation.

2.    Definitions.

      As used herein, the following terms have the meanings hereinafter set
forth unless the context clearly indicates to the contrary:

      2.1  "Applied Biosystems Stock" means the Applera Corporation - Applied
Biosystems Group Common Stock, par value $.01 per share.

      2.2  "Celera Stock" means the Applera Corporation - Celera Genomics Group
Common Stock, par value $.01 per share.

      2.3  "Committee" means the Management Resources Committee of the Board of
Directors of the Corporation, or any successor thereto or committee designated
thereby.

      2.4  "Common Stock" means Celera Stock and Applied Biosystems Stock and
either of them as the context requires.

      2.5  "Participant" means an employee to whom an award of Performance
Units has been granted under the Plan.

      2.6  "Performance Unit" means the right to receive a cash or stock
payment from the Corporation in the future upon the attainment of specified
Stock Price Targets and/or completion of a specified Vesting Period, as
provided in the Plan.

      2.7  "Stock Incentive Plan" means any of the Corporation's stock
incentive plans under which options for shares of Common Stock may be granted.

      2.8  "Stock Price Targets" means the stock price targets, if any,
applicable to a series of Performance Units established by the Committee at the
time of such award. For purposes hereof, a stock price target shall be deemed
attained at such time as the fair market value (as defined in the applicable
Stock Incentive Plan) of a share of Celera Stock or Applied Biosystems Stock,
as the case

                                      1

<PAGE>

may be, averages such stock price target over a period of 90 consecutive
calendar days after the date of grant of the applicable Performance Units.

      2.9  "Unit Value" means the value of a Performance Unit as determined
pursuant to Section 4.

      2.10  "Vesting Period" means the vesting period, if any, applicable to a
series of Performance Units established by the Committee at the time of such
award.

3.    Administration of the Plan.

      The Committee shall have plenary authority in its discretion, but subject
to the express provisions of the Plan, to administer the Plan. The Committee
shall also have plenary authority in its discretion to interpret the Plan, to
prescribe, amend, and rescind rules and regulations relating to it, and to make
any and all other determinations and take any and all actions deemed necessary
or advisable for the administration of the Plan. The Committee's determination
on the foregoing matters shall be conclusive and binding.

4.    Awards of Performance Units.

      At the time of grant of stock options under a Stock Incentive Plan, the
Committee may grant to any employee to whom options have been so granted such
number of Performance Units up to the number of stock options so granted.
Performance Units may be granted in one or more series, each series containing
such terms and conditions consistent with the Plan as the Committee shall
determine. The term of each Performance Unit shall be the term of the related
stock option, subject to earlier termination as hereinafter provided, and the
Unit Value of each Performance Unit shall be determined by the Committee but
shall be not more than the purchase price of the related option. Each
Performance Unit granted hereunder shall be evidenced by an agreement
containing such terms and conditions consistent with the Plan as the Committee
shall determine.

5.    Conditions to Payment of Performance Units.

      A Participant's right to receive payment of the Unit Value of Performance
Units awarded to him or her shall, except as provided below, be subject to such
conditions as the Committee shall establish, including, without limitation, the
attainment of one or more Stock Price Targets and/or satisfaction of one or
more Vesting Periods with respect to such Performance Units. Performance Units
shall not be affected by any change of duties or position so long as the holder
thereof continues to be an employee of the Corporation.

6.    Payment of Performance Units.

      6.1  Terms of Payment. Payment of the aggregate Unit Value of
Performance Units shall be made to Participants at such time and in such manner
as the Committee shall determine. Notwithstanding the foregoing, payment shall
be made in cash unless the Committee, in its sole discretion, determines to
make all or a portion of the payment in shares of the applicable class of
Common Stock. If payment is to be made in shares of Common Stock, or a
combination of such

                                      2

<PAGE>

shares and cash, any such issuance of shares of Common Stock may be made
subject to all applicable laws and regulations and to the approval of all
governmental authorities required in connection with the authorization,
issuance, sale, or transfer of shares of Common Stock.

      6.2  Deferrals. Notwithstanding the provisions of Section 6.1 above, to
the extent otherwise permissible under the terms of any deferred compensation
plan then offered by the Corporation, and subject to the terms thereof, a
Participant may elect to defer payment of the dollar value of the Unit Value
payable with respect to any Performance Units.

7.    Payment Upon Termination of Employment.

      7.1  Termination of Employment Prior to Attainment of Stock Price Targets
and/or Satisfaction of Vesting Periods. In the event that the employment of a
Participant shall terminate for any reason prior to any Stock Price Targets
having been attained and/or Vesting Periods having been satisfied, all
Performance Units granted to such Participant shall immediately terminate
without the payment of any consideration therefor.

      7.2  Termination of Employment Following Attainment of Stock Price
Targets and/or Satisfaction of Vesting Periods. In the event that the
employment of a Participant shall terminate following the attainment of one or
more Stock Price Targets and/or satisfaction of one or more Vesting Periods,
but prior to payment in full of the Unit Value of the applicable Performance
Units, the Performance Units corresponding to such Stock Price Targets and/or
Vesting Periods shall be payable as follows:

           7.2.1  Termination of Employment by a Participant or by the
      Corporation other than upon Retirement, Death, or Disability. In the
      event of termination of employment by a Participant or by the
      Corporation for any reason other than retirement, death or disability,
      all Performance Units granted to such Participant shall immediately
      terminate, regardless of whether any Stock Price Targets have been
      attained or Vesting Periods satisfied, without the payment of any
      consideration therefor, and no payment shall be made therefor after the
      date of termination.

           7.2.2  Termination Upon Retirement, Death, or Disability. In the
      event of termination of employment due to retirement from the Corporation
      in accordance with the terms of any pension or retirement plan provided
      by the Corporation, or if a Participant shall die while employed by the
      Corporation or become totally and permanently disabled, then the
      Performance Units as to which Stock Price Targets have been attained and/
      or Vesting Periods have been satisfied as of the date of such termination
      shall be paid to the Participant at such time as payment of the Unit
      Value of the Performance Units would otherwise be made pursuant to
      Section 6.1 hereof.

8.    Rights as a Stockholder.

      A Participant shall not be entitled to any rights or privileges of a
stockholder of the Corporation, except that the Committee may, in its sole
discretion, provide that such Participant shall be entitled to receive dividend
equivalents on one or more series of Performance Units if, as, and when paid on
shares of Celera Stock or Applied Biosystems Stock, as applicable. For
purposes of the payment of such dividend equivalents, each Performance Unit
shall be deemed equivalent to one

                                      3

<PAGE>

share of Celera Stock or Applied Biosystems Stock, as the case may be (subject
to adjustment as provided below).

9.    Acceleration Upon a Change of Control.

      Notwithstanding any other provision of the Plan or any Performance Unit
granted hereunder, all Stock Price Targets shall be deemed attained and all
Vesting Periods satisfied (i) in the event that a tender offer or exchange
offer (other than an offer by the Corporation) for the Common Stock
representing more than 25% of the combined voting power of the then outstanding
voting securities of the Corporation entitled to vote generally in the election
of directors ("Voting Securities") is made by any "person" within the meaning
of Section 14(d) of the Securities Exchange Act of 1934, as amended from time
to time (the "Act"), and not withdrawn within ten (10) days after the
commencement thereof; provided, however, that the Committee may by action taken
prior to the end of such ten (10) day period extend such ten (10) day period;
and, provided further, that the Committee may by further action taken prior to
the end of such extended period declare all Stock Price Targets to have been
attained and all Vesting Periods to have been satisfied, or (ii) in the event
of a Change in Control (as hereinafter defined).

      For purposes of this Section 9, a "Change in Control" means an event that
would be required to be reported (assuming such event has not been "previously
reported") in response to Item 1(a) of the Current Report on Form 8-K, as in
effect on the effective date of the Plan, pursuant to Section 13 or 15(d) of
the Act; provided, however, that, without limitation, such a Change in Control
shall be deemed to have occurred at such time as (a) any "person" within the
meaning of Section 14(d) of the Act becomes the "beneficial owner" as defined
in Rule 13d-3 thereunder, directly or indirectly, of more than 25% of the
combined voting power of the then outstanding Voting Securities, (b) during any
two-year period, individuals who constitute the Board of Directors (the
"Incumbent Board") as of the beginning of the period cease for any reason to
constitute at least a majority thereof, provided that any person becoming a
director during such period whose election or nomination for election by the
Corporation's stockholders was approved by a vote of at least three-quarters of
the Incumbent Board (either by a specific vote or by approval of the proxy
statement of the Corporation in which such person is named as a nominee for
director without objection to such nomination, other than in response to an
actual or threatened Change in Control or proxy contest) shall be, for purposes
of this clause (b), considered as though such person were a member of the
Incumbent Board, or (c) the approval by the Corporation's stockholders of the
sale of all or substantially all of the stock or assets of the Corporation.
The Committee may adopt such procedures as to notice and exercise as may be
necessary to effectuate the acceleration of the payment of the Unit Value of
Performance Units as described above.

10.   Performance Units Not Transferable.

      Performance Units may not be sold, assigned, bequeathed, transferred,
pledged, hypothecated, or otherwise disposed of in any way by the recipient
thereof. Any attempt to sell, pledge, assign, or transfer such rights shall be
void and unenforceable against the Corporation or any affiliate.

11.   Time of Granting Performance Units.

      Nothing contained in the Plan or in any resolution adopted by the Board
of Directors, the Committee, or the holders of Common Stock shall constitute
the grant of any Performance Units

                                      4

<PAGE>

hereunder. A Performance Unit shall be deemed to have been granted on the date
on which the name of the recipient and the terms of the Performance Unit are
set forth in an Agreement and delivered to the recipient, unless otherwise
provided in the Agreement.

12.   No Right to Continued Employment.

      Nothing contained in the Plan shall confer upon any employee the right to
continue in the employ of the Corporation or any subsidiary or interfere with
the right of the Corporation or such subsidiary to terminate such employee's
employment at any time.

13.   Adjustment Upon Changes in Capitalization.

      Notwithstanding any other provision of the Plan, in the event of changes
in the outstanding Celera Stock or Applied Biosystems Stock, as the case may
be, by reason of stock dividends, stock splits, recapitalizations, combinations
or exchanges of shares, corporate separations or divisions (including, but not
limited to, split-ups, split-offs, or spin-offs), reorganizations (including,
but not limited to, mergers or consolidations), liquidations, or other similar
events, the aggregate number of Performance Units granted under the Plan, the
dividend equivalent payments payable thereon, and the applicable Stock Price
Targets shall be adjusted in such manner as the Committee in its discretion
deems appropriate.

14.   Termination and Amendment of the Plan; Amendment of Awards.

      The Committee may terminate the Plan at any time or make such
modification or amendment to the Plan as it shall deem advisable. The
Committee may amend the terms of any award of Performance Shares granted
hereunder, including, without limitation, to permit the payment of the Unit
Value of any Performance Units to Participants under circumstances other than
those set forth in Section 7 above; provided, however, that no such amendment
shall adversely affect in any material manner any right of any Participant
without his or her consent.

15.   Miscellaneous.

      15.1  Withholding for Taxes. The Corporation shall have the right to
deduct from all payments under the Plan, or withhold from any distribution of
shares of Common Stock under the Plan, any taxes required by law to be withheld
with respect to such payments.

      15.2  Unfunded Status. The Plan is intended and at all times shall be an
unfunded and unsecured deferred compensation plan that is limited to key
management and other highly-compensated employees of the Corporation. Any
payments made under the Plan shall be paid from the general funds of the
Corporation, and no provision shall at any time be made with respect to
segregating assets of the Corporation for such payment hereunder. No
Participant or other person shall have any interest in any particular assets of
the Corporation by reason of a right to receive any payment or benefit under
the Plan, and any such Participant or other person shall have only the rights
of a general unsecured creditor of the Corporation with respect to any rights
under the Plan.

      15.3  Compliance with Laws. Notwithstanding anything to the contrary
contained in the Plan or otherwise, the Corporation shall not be obligated to
pay the Unit Value of any Performance Unit to

                                      5

<PAGE>

the extent that the aggregate amount payable would cause the Corporation to
violate any law or violate or breach any term of any loan, credit, or any other
material agreement of the Corporation or to which it or any of its assets are
bound or subject. If any payments are precluded from being made by reason of
the first sentence of this Section 15.3, such payments otherwise due shall be
made on a pro rata basis as and to the extent such applicable laws or
agreements shall permit.

      15.4  Governing Law. The Plan shall be construed, regulated, and
administered under the internal laws of the State of Delaware.

                                      6