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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                          -----------------------------


                                    FORM 10-K

                                  ANNUAL REPORT

                       Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934

                          -----------------------------

 For the fiscal year ended:                             Commission file number:
    December 31, 2005                                          001-32201

                          MERRILL LYNCH DEPOSITOR, INC.
                    (ON BEHALF OF PPLUS TRUST SERIES DCNA-1)
             (Exact name of registrant as specified in its charter)

               DELAWARE                                 13-3891329
            (State or other                         (I. R. S. Employer
            jurisdiction of                         Identification No.)
            incorporation)




        WORLD FINANCIAL CENTER,                           10080
          NEW YORK, NEW YORK                            (Zip Code)
         (Address of principal
          executive offices)

                          -----------------------------


              Registrant's telephone number, including area code: (212) 449-1000

Securities registered pursuant to Section 12(b) of the Act:

PPLUS Trust Certificates Series DCNA-1 listed on The New York Stock Exchange.

Securities registered pursuant to Section 12(g) of the Act:

Not Applicable.


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Indicate by check mark if the registrant is a well-known seasoned issuer, as
defined in Rule 405 of the Securities Act.

                                 Yes [ ] No [X]

Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Act.

                                 Yes [ ] No [X]


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was to
file such reports), and (2) has been subject to such filing requirements for the
past 90 days.

                                 Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [ ]

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Act).

                                 Yes [ ] No [X]

Indicate by check mark whether the registrant is a shell company (as defined in
Rule 12b-2 of the Exchange Act).

                                 Yes [ ] No [X]

State the aggregate market value of the voting and non-voting common equity held
by non-affiliates computed by reference to the price at which the common equity
was last sold, or the average bid and asked price of such common equity, as of
the last business day of the registrant's most recently completed second fiscal
quarter.

Not Applicable.

Indicate the number of shares outstanding for each of the registrant's classes
of common stock, as of the latest practicable date.

Not Applicable.

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                       DOCUMENTS INCORPORATED BY REFERENCE

None.



         PART I

         ITEM 1.           BUSINESS

                           For information with respect to the underlying
                           securities held by PPLUS Trust Series DCNA-1, please
                           refer to DaimlerChrysler AG's (Commission file number
                           001-14561) periodic reports, including reports on
                           Form 20-F and Form 6-K, and other information on file
                           with the Securities and Exchange Commission (the
                           "SEC"). You can read and copy these reports and other
                           information at the public reference facilities
                           maintained by the SEC at Room 1580, 100 F Street,
                           N.E., Washington, D.C. 20549. You may obtain copies
                           of this material for a fee by writing to the SEC's
                           Public Reference Section of the SEC at 100 F Street,
                           N.E., Washington, D.C. 20549. You may obtain
                           information about the operation of the Public
                           Reference Room by calling the SEC at 1-800-SEC-0330.
                           You can also access some of this information
                           electronically by means of the SEC's website on the
                           Internet at http://www.sec.gov, which contains
                           reports, proxy and information statements and other
                           information that the underlying securities guarantor
                           and the underlying securities issuer have filed
                           electronically with the SEC.

                           Although we have no reason to believe the information
                           concerning the underlying securities guarantee and
                           underlying securities or the underlying securities
                           guarantor and the underlying securities issuer
                           contained in the underlying securities guarantor's
                           Exchange Act reports is not reliable, neither the
                           depositor nor the trustee participated in the
                           preparation of such documents or made any due
                           diligence inquiry with respect to the information
                           provided therein. No investigation with respect to
                           the underlying securities guarantor and underlying
                           securities issuer (including, without limitation, no
                           investigation as to its financial condition or
                           creditworthiness) or of the underlying securities and
                           underlying securities guarantee has been made. You
                           should obtain and evaluate the same information
                           concerning the underlying securities issuer and the
                           underlying securities guarantor as you would obtain
                           and evaluate if your investment were directly in the
                           underlying securities or in other securities issued
                           by the underlying securities issuer or the underlying
                           securities guarantor. There can be no assurance that
                           events affecting the underlying securities and
                           underlying securities guarantee or the underlying
                           securities issuer and underlying securities guarantor
                           have not occurred or have not yet been publicly
                           disclosed which would affect the accuracy or
                           completeness of the publicly available documents
                           described above.

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         ITEM 1A.          RISK FACTORS

                           Your investment in trust certificates will involve
                           certain risks. You should carefully consider the
                           following discussion of risks, and the other
                           information included or incorporated by reference in
                           the applicable prospectus supplement and the
                           accompanying prospectus. You should also carefully
                           consider any risk factors and other information that
                           the underlying securities guarantor may file in their
                           Exchange Act reports as referenced in Item 1 above.

                           IF THE UNDERLYING SECURITIES ARE REDEEMED PRIOR TO
                           THEIR MATURITY DATE OR IF ANY CALL WARRANTS ARE
                           EXERCISED PRIOR TO THE STATED MATURITY DATE, YOU MAY
                           NOT BE ABLE TO REINVEST YOUR REDEMPTION OR CALL
                           PROCEEDS AT A YIELD COMPARABLE TO THE YIELD YOU WOULD
                           HAVE RECEIVED ON YOUR TRUST CERTIFICATES

                           The yield you will realize on your trust certificates
                           depends upon several factors, including:

                           o   the purchase price of the trust certificates,

                           o   when you acquire your trust certificates,

                           o   whether the underlying securities issuer
                               exercises its option to redeem the underlying
                               securities, and

                           o   whether the call warrant holders exercise their
                               optional rights to purchase outstanding trust
                               certificates.

                           The underlying securities issuer has the right to
                           redeem the underlying securities in whole, but not in
                           part, if it becomes obligated to pay additional
                           amounts. Because the underlying securities issuer has
                           the right to redeem the underlying securities early,
                           we cannot assure you that the trust will be able to
                           hold the underlying securities until their maturity
                           date.

                           Although the call warrant holders are not obligated
                           to exercise the call warrants, the yield you will
                           realize on your trust certificates depends on whether
                           the call warrant holders exercise their call warrants
                           to purchase the Class A trust certificates.

                           Prevailing interest rates at the time of an early
                           redemption or a call exercise may be lower than the
                           yield on your trust certificates. Therefore, you may
                           be unable to realize a comparable yield upon
                           reinvesting the funds you receive from an early
                           redemption or exercise of any call warrants. In
                           addition, if the prevailing market value of the trust
                           certificates exceeds the redemption price or call
                           exercise price paid to you upon a redemption of the
                           underlying securities or the exercise of a call, you
                           will not be able to realize such excess.


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                           YOU MAY NOT BE PAID IF THE ASSETS OF THE TRUST ARE
                           INSUFFICIENT

                           Currently, the trust has no significant assets other
                           than the underlying securities and the underlying
                           guarantee. If the underlying securities and the
                           underlying guarantee are insufficient to make
                           payments or distributions on the trust certificates,
                           no other assets will be available for payment of the
                           deficiency. The underlying securities issuer is
                           organized as a holding company that owns subsidiary
                           companies. According to the underlying securities
                           prospectus, the underlying securities issuer derives
                           its operating income and cash flow primarily from its
                           subsidiaries and investments, which poses two
                           principal risks:

                           o   the underlying securities issuer's right to
                               participate as an equity holder in any
                               distribution of assets of any of its subsidiaries
                               upon the subsidiary's liquidation or otherwise,
                               and thus the ability of its security holders,
                               including the trust, to benefit from the
                               distribution, will be subject to prior claims of
                               the subsidiary's creditors, except to the extent
                               that any claims the underlying securities issuer
                               may have as a creditor of the subsidiary are
                               recognized, and

                           o   the underlying securities issuer's ability to
                               service its indebtedness and other obligations is
                               dependent primarily upon the earnings and cash
                               flow of its subsidiaries and the distribution or
                               other payment to it of such earnings and cash
                               flow.

                           YOU MAY NOT RECOVER THE WHOLE OF THE PRESENT VALUE OR
                           STATED AMOUNT (IF APPLICABLE) OF YOUR TRUST
                           CERTIFICATES IF THE TRUST DISPOSES OF THE UNDERLYING
                           SECURITIES ON A DEFAULT BY THE UNDERLYING SECURITIES
                           ISSUER OR IN THE EVENT THE UNDERLYING SECURITIES
                           GUARANTOR CEASES FILING EXCHANGE ACT REPORTS

                           If the underlying securities issuer defaults on its
                           obligations under the underlying securities or the
                           underlying securities guarantor ceases to file
                           Exchange Act reports or ceases to be in compliance
                           with Rule 3-10 of Regulation S-X under the Securities
                           Act, then the trust will either distribute the
                           underlying securities to the trust certificateholders
                           or dispose of them and distribute the proceeds to the
                           trust certificateholders. Your recovery in either of
                           those events may be limited by two factors:


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                           o   if a default occurs, the market value of the
                               underlying securities may be adversely affected
                               and the proceeds of their disposition may be
                               lower than the aggregate present value or stated
                               amount (if applicable) of the trust certificates;
                               and

                           o   in either event, any distribution of funds or
                               underlying securities by the trust to the trust
                               certificateholders will be done in accordance
                               with the allocation ratio as described in the
                               applicable prospectus supplement relating to the
                               trust certificates. The funds or aggregate
                               principal amount of underlying securities you
                               receive on that distribution may be less than the
                               present value or stated amount (if applicable) of
                               your trust certificates.

                           THE TRUSTEE WILL NOT MANAGE THE UNDERLYING SECURITIES

                           Except as described below, the trust will not dispose
                           of any underlying securities, even if an event occurs
                           that adversely affects the value of the underlying
                           securities or that adversely affects the underlying
                           securities issuer or the underlying securities
                           guarantor. As provided in the applicable trust
                           agreement, the trust will dispose of the underlying
                           securities only if:

                           o   there is a payment default on any underlying
                               securities,

                           o   there is another type of default that accelerates
                               the maturity of the underlying securities, or

                           o   the underlying securities guarantor ceases to
                               file Exchange Act reports or ceases to be in
                               compliance with Rule 3-10 of Regulation S-X under
                               the Securities Act.

                           Under the first circumstance listed above, the
                           trustee must sell the underlying securities on behalf
                           of the trust, even if adverse market conditions
                           exist. The trustee has no discretion to do otherwise.
                           If adverse market conditions do exist at the time of
                           the trustee's sale of the underlying securities, you
                           may incur greater losses than if the trust continued
                           to hold the underlying securities.

                           THE TRUST CERTIFICATES ARE SUBJECT TO THE
                           CREDITWORTHINESS OF THE UNDERLYING SECURITIES
                           ISSUER AND THE UNDERLYING SECURITIES GUARANTOR

                           The trust certificates represent interests in
                           obligations of the underlying securities issuer and
                           the underlying securities guarantor. In particular,
                           the trust certificates will be subject to all the
                           risks associated with directly investing in the
                           underlying securities guarantor's unsecured debt
                           obligations. None of the underlying indenture, the
                           underlying securities or the guarantee places a
                           limitation on the amount of indebtedness that may be
                           incurred by the underlying securities issuer or
                           underlying securities guarantor.

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                           THE PAYMENTS OWED TO THE TRUST CERTIFICATEHOLDERS ARE
                           UNSECURED OBLIGATIONS

                           In a liquidation, holders of the underlying
                           securities, including the trust, will be paid only
                           after holders of secured obligations of the
                           underlying securities issuer. According to the
                           underlying securities prospectus, the underlying
                           securities are unsecured and rank equally with all
                           other unsecured and unsubordinated indebtedness of
                           the underlying securities issuer.

                           THE RATINGS OF THE TRUST CERTIFICATES MAY CHANGE

                           At the time of issuance, Moody's and S&P assigned
                           ratings to the trust certificates equivalent to the
                           ratings of the underlying securities, as of the date
                           of the applicable prospectus.

                           Any rating issued with respect to the trust
                           certificates is not a recommendation to purchase,
                           sell or hold a security. Ratings do not comment on
                           the market price of the trust certificates or their
                           suitability for a particular investor. We cannot
                           assure you that initial ratings will remain for any
                           given period of time or that a ratings agency would
                           not revise or withdraw entirely the ratings if, in
                           its judgment, circumstances (including, without
                           limitation, the rating of the underlying securities)
                           merit. A revision or withdrawal of a rating may
                           adversely affect the market price of the trust
                           certificates.

         ITEM 1B.          UNRESOLVED STAFF COMMENTS

                           Not Applicable.

         ITEM 2.           PROPERTIES

                           None.

         ITEM 3.           LEGAL PROCEEDINGS

                           None.

         ITEM 4.           SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

                           None.

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         PART II

         ITEM 5.           MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED
                           STOCKHOLDER MATTERS AND ISSUER PURCHASES OF
                           EQUITY SECURITIES

                           The Trust Certificates issued by PPLUS Trust Series
                           DCNA-1 are represented by one or more physical
                           certificates registered in the name of Cede & Co.,
                           the nominee of the Depository Trust Company. The
                           Trust Certificates are listed on the New York Stock
                           Exchange.

         ITEM 6.           SELECTED FINANCIAL DATA

                           Not Applicable.

         ITEM 7.           MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                           CONDITION AND RESULTS OF OPERATIONS

                           Not Applicable.

         ITEM 7A.          QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET
                           RISK

                           Not Applicable.

         ITEM 8.           FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                           Not Applicable.

         ITEM 9.           CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON
                           ACCOUNTING AND FINANCIAL DISCLOSURE

                           None.

         ITEM 9A.          CONTROLS AND PROCEDURES

                           The Registrant has procedures so as to provide
                           reasonable assurance that its future Exchange Act
                           filings will be filed within the applicable time
                           periods.

         ITEM 9B.          OTHER INFORMATION

                           None.

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         PART III

         ITEM 10.          DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

                           Not Applicable.

         ITEM 11.          EXECUTIVE COMPENSATION

                           Not Applicable.

         ITEM 12.          SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND
                           MANAGEMENT AND RELATED STOCKHOLDER MATTERS

                           (a) Securities Authorized For Issuance Under Equity
                               Compensation Plans: None.
                           (b) Security Ownership Of Certain Beneficial Owners:
                               None.
                           (c) Security Ownership Of Management: Not Applicable.
                           (d) Changes In Control: None.

         ITEM 13.          CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

                           None.

         ITEM 14.          PRINCIPAL ACCOUNTING FEES AND SERVICES

                           Not Applicable.

         PART IV

         ITEM 15.          EXHIBITS, FINANCIAL STATEMENT SCHEDULES

                           (a)(1) Financial Statements: Not Applicable.

                           (a)(2) Financial Statement Schedules: Not Applicable.

                           (a)(3) List of Exhibits

                           The following exhibits are filed as part of, and
                           incorporated by reference into, this Annual Report on
                           Form 10-K:

                                    31.1    Certification of President of
                                            Registrant dated March 27, 2006,
                                            pursuant to Rules 13a-14 and 15d-14
                                            under the Securities Exchange Act of
                                            1934, as adopted pursuant to Section
                                            302 of the Sarbanes-Oxley Act of
                                            2002, with respect to the
                                            Registrant's Annual Report on Form
                                            10-K for the year ended December 31,
                                            2005.

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                                    99.1    Trustee's Annual Compliance
                                            Certificate dated February 21, 2006.

                                    99.2.   Report of Deloitte & Touche LLP,
                                            Independent Registered Public
                                            Accounting Firm, dated March 24,
                                            2006, Registrant's Assertion on
                                            Compliance with PPLUS Minimum
                                            Servicing Standards dated March 24,
                                            2006 and PPLUS Minimum Servicing
                                            Standards.

                                    99.3.   Report of Ernst & Young LLP,
                                            Independent Registered Public
                                            Accounting Firm, dated February 21,
                                            2006, The Bank of New York's
                                            Assertion on Compliance with PPLUS
                                            Minimum Servicing Standards dated
                                            February 21, 2006 and PPLUS Minimum
                                            Servicing Standards.

                                (b) Exhibits

                                    The Registrant hereby files as part of this
                                    Annual Report on Form 10-K the exhibits
                                    listed in Item 15(a)(3) set forth above.

                                (c) Financial Statement Schedules

                                    Not applicable.

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                                   SIGNATURES

                  Pursuant to the requirements of Section 13 or 15(d) of the
Securities Exchange Act of 1934, the registrant has duly caused this report to
be signed on its behalf by the undersigned, hereunto duly authorized.

                                    MERRILL LYNCH DEPOSITOR, INC.

Date: March 27, 2006                By: /s/ Stephan Kuppenheimer
                                       -----------------------------------------
                                             Name:    Stephan Kuppenheimer
                                             Title:   President

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