**EXHIBIT 31.1**

**CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICERPURSUANT TO EXCHANGE ACT RULE 13a-14(a)/15d-14(a),AS ADOPTED PURSUANT TO SECTION 302 OFTHE SARBANES-OXLEY ACT OF 2002**

I, Tony L. White, certify that:

| 1.     |   | I have reviewed this annual report on Form 10-K of Applera Corporation;                                                                                                                                                                                                                                                                                                                                          |
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| 2.     |   | Based on my knowledge, this report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading with respect to the period coveredby this report;                                                                                                          |
|   |   |                                                                                                                                                                                                                                                                                                                                                                                                             |
| 3.     |   | Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;                                                                                                                          |
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| 4.     |   | The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:                                                                                                                                                                              |
|   |   |                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   | (a)  Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;                              |
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|   |   | (b)  [Omitted pursuant to SEC Release Nos. 33-8238 and 34-47986];                                                                                                                                                                                                                                                                                                                                                |
|   |   |                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   | (c)  Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and                                                                                                                    |
|   |   |                                                                                                                                                                                                                                                                                                                                                                                                             |
|   |   | (d)  Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and |
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| 5.     |   | The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of registrant’s board of directors (or persons performing the equivalent functions):                                                                                                    |

 

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|   |   | (a) All significant deficiencies        and material weaknesses in the design or operation of internal control        over financial reporting which are reasonably likely to adversely affect        the registrant’s ability to record, process, summarize and report    financial information; and |
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|   |   |                                                                                                                                                                                                                                                                                                       |
|   |   | (b)  Any fraud, whether or not    material, that involves management or other employees who have a significant    role in the registrant’s internal control over financial reporting.                                                                                                                 |

Date:  September 25, 2003

|   | /s/ Tony L. White       |   |
|--------|-------------------------|--------|
|   |                         |   |
|   | Chief Executive Officer |   |

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