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                                                                    EXHIBIT 10.3
                                                                    ------------
                           STOCK  PURCHASE  AGREEMENT
                           --------------------------

     THIS STOCK PURCHASE Agreement ("Agreement") dated as of the 18th day of
March, 1997 among PONTOTOC BANCSHARES CORP., a Mississippi corporation
("BancShares"), FIRST NATIONAL BANK OF PONTOTOC, a national banking association
(the "Bank"), UNION PLANTERS CORPORATION, a Tennessee corporation ("UPC"), DOTY
INVESTMENTS, L.P., a Mississippi limited partnership ("Doty Investments"),
MARTHA W. DOTY of Birmingham, Alabama ("Doty"), GERRY G. JONES of Jackson,
Mississippi ("Jones") and ALL SAINTS EPISCOPAL CHURCH OF MEMPHIS, TENNESSEE
("All Saints").  UPC, Doty Investments, Doty, Jones and All Saints are sometimes
referred to as Seller or collectively as Sellers.

                                R E C I T A L S

     WHEREAS, UPC entered into a certain Stock Purchase Agreement with Doty
Investments, Doty, Jones and All Saints dated as of October 17, 1996 (the
"UP/Doty Agreement") in which, subject to certain conditions, UPC agreed to
purchase and the other parties agreed to sell certain shares of common stock in
the Bank (the "Bank Stock");

     WHEREAS, on December 31, 1997, pursuant to the UP/Doty Agreement, UPC
purchased two hundred sixty-four (264) shares of the Bank Stock from All Saints
(the "All Saints Stock") and entered into an agreement with All Saints that day
regarding certain continuing obligations from UPC to All Saints (the "All Saints
Agreement");

     WHEREAS, the UP/Doty Agreement was modified and extended by letter
agreements dated December 13, 1996, December 31, 1996 and January 13, 1997,
respectively (collectively, the "UP/Doty Extension");

     WHEREAS, the Bank entered into Stock Purchase Agreements with Doty
Investments, Doty and Jones, each dated as of January 31, 1997 (collectively,
the "Bank/Doty Agreements"), in which the Bank agreed, subject to certain
conditions, to purchase (or cause to be purchased) and the other parties agreed
to sell the Bank Stock (not including the All Saints Stock);

     WHEREAS, UPC, Doty Investments, Doty, Jones and All Saints wish to
terminate the UP/Doty Agreement (as extended by the UP/Doty Extension) pursuant
to Section 9.1(a) of the UP/Doty Agreement and the All Saints Agreement and to
fully and unconditionally release one another from any further obligations or
liability of any nature whatsoever with respect to the Doty Agreement (as
extended by the UP/Doty Extension) and the All Saints Agreement (subject,
however, to the exceptions specifically set forth in this Agreement), and Doty
Investments, Doty, Jones, BancShares and the Bank wish to make certain
modifications to the Bank/Doty Agreements, and all parties wish to enter into
certain other agreements;
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     NOW, THEREFORE, the parties agree as follows:

                                   ARTICLE 1.

                       CANCELLATION OF UP/DOTY AGREEMENT
                            AND ALL SAINTS AGREEMENT

     UPC, Doty Investments, Doty, Jones and All Saints agree that the UP/Doty
Agreement, the UP/Doty Extension and the All Saints Agreement will each be
terminated by mutual consent effective at the time of the UPC Closing, as
defined below.  Thereafter, no party to the UP/Doty Agreement, the UP/Doty
Extension or the All Saints Agreement will have any further rights or
obligations under the respective agreements except as set for in Paragraph 10.11
of the UP/Doty Agreement which shall survive the UPC Closing and except that the
representations and warranties of All Saints in Article 5 of the UP/Doty
Agreement shall survive the UPC Closing.

                                   ARTICLE 2.

                       AMENDMENTS TO BANK/DOTY AGREEMENTS

     The Bank, Doty Investments, Doty and Jones, respectively, agree that the
Bank/Doty Agreements are amended as follows effective upon the UPC Closing:

     2.1.  Paragraph 2.2, Closing, of the Bank/Doty Agreement with Doty
Investments is amended by deleting the words "not prior to April 1, 1997 and in
any event" from Paragraph 2.2 so that Paragraph 2.2 of the agreement reads as
follows:

                2.2. Closing. A closing (the "Closing") shall be held at the
           offices of the Company on a date (the "Closing Date") and at the time
           of day to be agreed upon by the parties, no later than May 31, 1997.
           At the Closing, the Shareholder shall deliver to the Company stock
           certificates evidencing and representing the FNB Stock duly endorsed
           in blank for transfer or accompanied by appropriate stock powers duly
           executed in blank.

     2.2. Paragraph 2.2, Closing, of the Bank/Doty Agreement with Martha W. Doty
and Gerry G. Jones is amended by deleting the words "not prior to April 1, 1997
and in any event" from Paragraph 2.2 so that Paragraph 2.2 of the agreements
reads as follows:

                2.2. Closing. A closing (the "Closing") shall be held at the
           offices of the Company on a date (the "Closing Date") and at the time
           of day to be agreed upon by the parties, no later than April 11,
           1997. At the Closing, the Shareholder shall deliver to the Company
           stock certificates evidencing and representing the FNB Stock duly
           endorsed in blank for transfer or accompanied by appropriate stock
           powers duly executed in blank.

                                       2
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     2.3.  Paragraph 5.1, Ownership:  No Liens or Impediments to Transfer, of
the Bank/Doty Agreement with Doty Investments is amended by deleting the
reference to the UPC Agreement in Paragraph 5.1 so that Paragraph 5.1 of the
agreement with Doty Investments reads as follows:

                5.1. Ownership: No Liens or Impediments to Transfer. The
           Shareholder beneficially owns 4,936 shares of stock in the Company.
           All such shares of FNB Stock are owned free and clear of any liens or
           encumbrances of any nature, and when transferred by the Shareholder
           to the Company in accordance with this Agreement, such shares will be
           transferred free and clear of any liens or encumbrances, and the
           Shareholder has not directly or indirectly, entered into any
           agreement or arrangement of any nature to sell, transfer, assign,
           pledge, lend, hypothecate or alienate in any manner the stock, or
           entered into a voting trust or similar arrangement with respect to
           the voting of such shares other than this Agreement.

     2.4.  Paragraph 5.1, Ownership:  No Liens or Impediments to Transfer, of
the Bank/Doty Agreement with Doty is amended by deleting the reference to the
UPC Agreement in Paragraph 5.1 so that Paragraph 5.1 of the agreement with Doty
reads as follows:

                5.1. Ownership: No Liens or Impediments to Transfer. The
           Shareholder beneficially owns 250 shares of stock in the Company. All
           such shares of FNB Stock are owned free and clear of any liens or
           encumbrances of any nature, and when transferred by the Shareholder
           to the Company in accordance with this Agreement, such shares will be
           transferred free and clear of any liens or encumbrances, and the
           Shareholder has not directly or indirectly, entered into any
           agreement or arrangement of any nature to sell, transfer, assign,
           pledge, lend, hypothecate or alienate in any manner the stock, or
           entered into a voting trust or similar arrangement with respect to
           the voting of such shares other than this Agreement.

     2.5.  Paragraph 5.1, Ownership:  No Liens or Impediments to Transfer, of
the Bank/Doty Agreement with Jones is amended by deleting the reference to the
UPC Agreement in Paragraph 5.1 so that Paragraph 5.1 of the agreement with Jones
is amended to read as follows:

                5.1. Ownership: No Liens or Impediments to Transfer. The
           Shareholder beneficially owns 1,107 shares of stock in the Company.
           All such shares of FNB Stock are owned free and clear of any liens or
           encumbrances of any nature, and when transferred by the Shareholder
           to the Company in accordance with this Agreement, such shares will be
           transferred free and clear of any liens or encumbrances, and the
           Shareholder has not directly or indirectly, entered into any
           agreement or arrangement of any nature to sell, transfer, assign,
           pledge, lend, hypothecate or alienate in any manner the stock, or
           entered into a voting trust or

                                       3
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           similar arrangement with respect to the voting of such shares other
           than this Agreement.

     2.6.  Paragraph 9.1, Termination, is amended by deleting subparagraph (d)
of Paragraph 9.1 so that Paragraph 9.1 of each Bank/Doty Agreement reads as
follows:

                9.1. Termination. This Agreement may be terminated at any time
           prior to the Closing, as follows:

                      (a) By mutual consent in writing of the Company and the
                          Shareholder;

                      (b) By the Company if the conditions set forth in Sections
                          8.2 or 8.3 shall not have been satisfied in all
                          material respects as of the Closing Date, or by the
                          Shareholder if the conditions set forth in Section 8.1
                          or 8.3 shall not have been satisfied in all material
                          respects as of the Closing Date, and such failures
                          shall not have been waived prior to the Closing;

                      (c) At its option, by the Company or by the Shareholder if
                          there shall have been a material breach of any
                          obligation of the other party and such breach shall
                          not have been remedied within thirty (30) days after
                          receipt by the breaching party of written notice from
                          the other party specifying the nature of such breach
                          and requesting that it be remedied.

     If a party should elect to terminate this Agreement pursuant to subsections
(b) or (c) of this Section 9.1, it shall give notice to the other party, in
writing, of its election in the manner prescribed in Section 10.1.

                                   ARTICLE 3.

                         PURCHASE OF ALL SAINTS STOCK/
                       CANCELLATION OF UP/DOTY AGREEMENT
                            AND ALL SAINTS AGREEMENT

     3.1. UPC and BancShares agree as follows:

          (a) UPC agrees to sell and BancShares agrees to purchase the All
Saints Stock. UPC, Doty Investments, Doty, Jones and All Saints agree to
terminate the UP/Doty Agreement (as modified by the UP/Doty Extension), and UPC
and All Saints agree to terminate the All Saints

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Agreement, as of the effective time of the UPC Closing (as defined below), in
accordance with the provisions of Article 1 of this Agreement and Section 9.1(a)
of the UP/Doty Agreement.

          (b) BancShares agrees to pay to UPC, by wire transfer of same day
funds to an account designated by UPC, Two Hundred Thirty-Four Thousand Three
Hundred Dollars ($234,300.00) in consideration for the purchase of the All
Saints Stock and Five Hundred Seventy-Five Thousand Dollars ($575,000.00) in
consideration for UPC's agreement to terminate the UP/Doty Agreement (and the
UP/Doty Extension).  At the time of the UPC Closing, UPC will pay to All Saints
the sum of Ten Thousand Four Hundred Twenty-Eight Dollars ($10,428.00) as
additional purchase price for the All Saints Stock so that the total purchase
price per share paid by UPC to All Saints for the All Saints Stock (when added
to that already paid to All Saints) will be Eight Hundred Eighty-Seven Dollars
and Fifty Cents ($887.50) per share.

          (c) A Closing (the "UPC Closing") shall take place at a mutually
agreeable time and place no later than March 18, 1997.  All payments being made
pursuant to this Article 3 shall be made at the UPC Closing.

          (d) Except as provided in the last sentence of this subparagraph,
effective as of the time of the UPC Closing, Doty Investments, Doty, Jones and
All Saints, for themselves, their heirs, successors and assigns, do release and
forever discharge UPC from any and all liability or obligation of any nature
arising from the UP/Doty Agreement, the UP/Doty Extension and the All Saints
Agreement, respectively, and from any and all liability of any nature arising
from the transactions contemplated in the foregoing agreements.  Likewise,
effective as of the time of the UPC Closing, UPC, for itself, its successors and
assigns, does release and forever discharge Doty Investments, Doty, Jones and
All Saints from any and all liability or obligation of any nature arising from
the UP/Doty Agreement, the UP/Doty Extension and the All Saints Agreement,
respectively, and from any and all liability of any nature arising from the
transactions contemplated in the foregoing agreements.  This release shall not
affect the parties' obligations under Paragraph 10.11 of the UP/Doty Agreement,
nor shall it affect the warranties of All Saints in Article 5 of the UP/Doty
Agreement.

                                   ARTICLE 4.

                              PURCHASE OF STOCK OF
                        DOTY INVESTMENTS, DOTY AND JONES

     Doty Investments, Doty and Jones agree to sell their shares of Bank Stock
(being 4,936, 250 and 1,107 shares, respectively) to BancShares and BancShares
agrees to purchase such shares for the purchase price of Eight Hundred Eighty-
One Dollars and Fifty Cents ($881.50) per share payable in readily available
funds at Closing.  A Closing (the "Doty Closing") shall be held at a time and
place mutually agreeable to the parties, but in no event later than April 11,
1997 in the case of the purchase from Doty and Jones, or later than May 31, 1997
in the case of the purchase from Doty Investments.

                                       5
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                                   ARTICLE 5.

                           PURCHASE PRICE ADJUSTMENT

     5.1.  General.  The purchase price of the shares of the Bank Stock
(including the All Saints Stock) shall be adjusted in the case of any
reclassification, reorganization, recapitalization, stock split, reverse stock
split, stock dividend or distribution, subdivision, combination or exchange of
the outstanding shares of the Bank, or reorganization of the Bank as a wholly
owned subsidiary of a bank holding company, so that BancShares shall be entitled
to acquire all of the shares of Bank common stock and other capital stock of the
Bank or capital stock issued in any combination or exchange for the former Bank
stock, beneficially owned or controlled by the selling party for the same
aggregate consideration as if such transaction had not occurred.  This provision
shall similarly apply to successive reclassifications, reorganizations, stock
dividends or distributions, subdivisions, combinations or exchanges,
consolidations, mergers, sales or transfers.

     5.2.  Doty Investments Stock.  If the Bank Stock has not been purchased
from Doty Investments on or before April 11, 1997, the purchase price (for any
Bank Stock not purchased on or before April 11, 1997) shall be increased by Nine
Dollars ($9.00) per share.  If the closing has not occurred by May 1, 1997, the
purchase price (for any Bank Stock not purchased on or before May 1, 1997) shall
be increased by an additional Ten Dollars ($10.00) per share.  If the closing
has not occurred on or before April 11, 1997, BancShares shall pay to Doty
Investments a non-refundable earnest money payment of ten percent (10%) of the
purchase price.

                                   ARTICLE 6.

                  REPRESENTATIONS AND WARRANTIES OF BANCSHARES

     Both on the date hereof and as of each Closing, BancShares represents and
warrants to UPC, Doty Investments, Doty and Jones as follows:

     6.1.  Organization and Corporate Authority.  BancShares is a Mississippi
corporation duly organized, validly existing and in good standing under the laws
of the State of Mississippi.

     6.2.  Authorization, Execution and Delivery; No Breach.

           (a) BancShares has all requisite corporate power and authority to
execute and deliver this Agreement and to consummate the transactions
contemplated in this Agreement; provided, however, that approval from the
applicable regulatory authorities will be necessary for BancShares to actually
purchase more than five percent (5%) of the outstanding Bank Stock.  This
Agreement has been duly executed and delivered by BancShares; has been
effectively authorized by all necessary corporate action; and, upon execution
and delivery, will constitute the legal, valid and enforceable obligation of
BancShares, subject, as to enforceability, to applicable bankruptcy,

                                       6
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insolvency, reorganization, moratorium or similar laws affecting the enforcement
of creditors' rights generally, and to the application of equitable principles
and judicial discretion.

          (b) The execution and delivery of this Agreement, the payments being
made to UPC, the purchase of the Bank Stock and the fulfillment of the terms
hereof will not result in a violation or breach of any of the terms or
provisions of, or constitute a default under (or an event which, with the
passage of time or the giving of notice or both, would constitute a default
under), or conflict with, or permit the acceleration of any obligation under,
any material mortgage, lease, covenant, agreement, indenture or other instrument
to which BancShares is a party or by which BancShares or any of its material
assets are bound; the corporate charter and bylaws of BancShares; or any
material judgment, decree, order or award of any court, governmental body or
arbitrator by which BancShares is bound; or any material permit, concession,
grant, franchise, license, law, statute, ordinance, rule or regulation
applicable to BancShares; or result in the creation of any lien, claim, security
interest, encumbrance, charge, restriction or right of any third party of any
kind whatsoever upon the property or assets of BancShares.

     6.3.  No Legal Bar.  BancShares is not a party to, subject to or bound by
any agreement, judgment, order, letter of understanding, writ, prohibition,
injunction or decree of any court or other governmental body of competent
jurisdiction, or any law which would prevent the execution and delivery of this
Agreement, the payments to be made to UPC or the purchase of the Bank Stock, and
no action or proceeding is pending or, to the best of the knowledge of
BancShares, threatened against BancShares in which the validity of this
Agreement, the payments to be made to UPC, the purchase by BancShares of the
Bank Stock or any action which has been taken by any of such parties in
connection herewith or in connection with any of the transactions contemplated
hereby is at issue.

     6.4.  Government and Other Approvals.  No consent, approval, order or
authorization of, or registration, declaration or filing with, any federal,
state or local governmental authority is required to be made or obtained by
BancShares in connection with the execution and delivery of this Agreement, the
consummation of the transactions contemplated in Article 3 of this Agreement, or
purchase of the Bank Stock from the Sellers contemplated hereby, except the
prior approval of the Board of Governors of the Federal Reserve System is
required for BancShares to actually purchase five percent (5%) or more of the
outstanding Bank Stock.  Other than receipt of such bank regulatory approval,
which is not applicable to the transactions contemplated by Article 3 of this
Agreement, or to the purchase of the Bank Stock from Doty and Jones, BancShares
is not aware of any other fact that would lead it to believe that any other
approval is required or necessary for it to consummate each of the transactions
contemplated by this Agreement.

                                       7
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                                 ARTICLE 7.

                   REPRESENTATIONS AND WARRANTIES OF SELLERS

          Both as of the date hereof and as of each applicable Closing, Sellers
severally represent and warrant (as to themselves, but not for any others) to
BancShares as follows:

          7.1.  Ownership:  No Liens or Impediments to Transfer.  Seller (other
than All Saints) beneficially owns the number of shares of Bank Stock set forth
in this Agreement.  All such shares are owned free and clear of any liens or
encumbrances of any nature, and when transferred by Seller in accordance with
this Agreement, such shares will be transferred free and clear of any liens or
encumbrances, and each party has not directly or indirectly, entered into any
agreement or arrangement of any nature to sell, transfer, assign, pledge, lend,
hypothecate or alienate in any manner the stock or entered into a voting trust
or similar arrangement with respect to the voting of such shares other than this
Agreement, the UP/Doty Agreement and, in the case of Doty Investments, Doty and
Jones, the Bank/Doty Agreements.  All Saints owns no shares of Bank Stock.

          7.2.  Authority.

                (a) Seller has all requisite power and authority to execute and
deliver this Agreement, to abide by the covenants made hereunder, and to
consummate the transactions contemplated hereby.  This Agreement has been duly
executed and delivered by or on behalf of Seller and constitutes the legal,
valid and enforceable obligations of Seller, subject, as to enforceability, to
applicable bankruptcy, insolvency, receivership, conservatorship,
reorganization, moratorium or similar laws affecting the enforcement of
creditors' rights generally and to the application of equitable principles and
judicial discretion.

                (b) The execution and delivery of this Agreement, the
consummation of the transactions contemplated hereby, and the fulfillment of the
terms hereof, will not result in a violation or breach of any of the terms or
provisions of, or constitute a default under (or an event which, with the
passage of time or the giving of notice, or both, would constitute a default
under) or conflict with, or permit the acceleration of, a material obligation
under any material mortgage, lease, covenant, agreement, indenture or other
instrument to which Seller is a party or by which Seller is bound, directly or
indirectly; or any material judgment, decree, order, regulatory letter of
understanding or award of any court, governmental body, authority or arbitrator
by which Seller is directly or indirectly bound; or any material permit,
concession, grant, franchise, license, law, statute, ordinance, rule or
regulation, applicable to Seller or Seller's properties or any of them; or
result in the creation of any lien, claim, security interest, encumbrance,
charge, restriction or right of any third party of any kind whatsoever upon the
Bank Stock or upon any rights of Seller to receive the purchase price to be paid
pursuant to this Agreement.

                                       8
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          7.3.  No Legal Bar.  At the UPC Closing or the Doty Closing, as
applicable, Seller will not be bound by any agreement, judgment, order, letter
of understanding, writ, prohibition, injunction or decree of any court or other
governmental authority or body, or any law which would prevent the execution and
delivery of this Agreement or the fulfillment of the terms hereof by Seller.  No
action or proceeding is pending against Seller which questions the validity of
this Agreement or the transactions contemplated hereby.

          7.4.  Government and Other Approvals.  No consent, approval, order or
authorization of, or registration, declaration or filing with any federal, state
or local governmental authority, landlord, licensor, shareholder, court,
administrative agency, co-owner, spouse, trustee, co-trustee, beneficiary or
other party is required to be made or obtained by Seller in connection with the
execution and delivery of this Agreement, the fulfillment of the terms hereof by
Seller, which have not already been obtained and which are in full force and
effect.

                                   ARTICLE 8.

                            COVENANTS OF BANCSHARES

          8.1.  Regulatory Approvals.  BancShares shall obtain the necessary
government approvals to acquire the Bank Stock from Doty Investments, Doty and
Jones.  BancShares shall pay all fees and expenses arising in connection with
such applications for regulatory approval applicable to it. BancShares agrees to
obtain such regulatory approvals and any other approvals and consents as may be
required as promptly as practicable.

          8.2.  Failure to Obtain Regulatory Approvals.  If BancShares cannot
obtain the required regulatory approvals to purchase the Bank Stock from Doty
Investments by May 10, 1997, it may assign its rights under this Agreement to a
person or persons not subject to such regulatory approvals and take such other
action as is necessary in order that the transaction can be closed on or before
May 31, 1997.  BancShares shall advise Doty Investments in writing by May 15,
1997 of such assignment and the details of the assignees' obligations.  Such
assignment shall not relieve BancShares from its obligations to Doty Investments
as set forth in this Agreement.

                                   ARTICLE 9.

                              COVENANTS OF SELLERS

          Sellers severally agree as follows:

          9.1.  Dissenter's Rights.  Seller shall not exercise dissenter's
rights in connection with the merger of the Bank into an interim bank in
connection with the formation by BancShares of a holding company under the Bank
Holding Company Act; provided however, in the event that BancShares has not
purchased (or caused to be purchased) the Bank Stock from Doty and Jones by
April 11, 1997, or from Doty Investments by June 1, 1997, any Seller from whom
stock has

                                       9
<PAGE>
 
not been purchased may demand dissenter's rights from the Bank, and in such
event, for purposes of such a dissent proceeding, Sellers and Bank agree that
the value of the Bank Stock shall be Nine Hundred Ten Dollars ($910.00) per
share.  Each party will vote its shares in favor of the merger of the Bank into
an interim bank as a part of the formation of a bank holding company if
recommended by the Board of Directors of the Bank.

          9.2.  No Additional Shares.  After the date of this Agreement and
prior to the UPC Closing and the Doty Closing, Sellers shall not voluntarily
acquire, offer to acquire or solicit offers to sell, any additional shares of
common stock of the Bank or any capital stock of BancShares.  Nothing herein
shall be deemed to prohibit a seller from acquiring additional shares of common
stock of the Bank or other capital stock of the Bank pursuant to a dividend or
other distribution undertaken by the Bank, or to acquire additional shares of
common stock of the Bank or other capital stock by operation of law or by
descent and distribution.

          9.3.  Further Assistance.  Sellers shall give such further assistance
to BancShares and to UPC and shall execute, acknowledge and deliver all such
documents and instruments as BancShares or UPC (in respect of the UPC Closing)
may reasonably request, and take such further action as may be necessary or
appropriate effectively to consummate the transactions contemplated by this
Agreement.

                                  ARTICLE 10.

                             CONDITIONS TO CLOSING

          10.1.  Conditions to the Obligations of Sellers to UPC Closing.
Unless waived in writing by a Seller, the obligation of each Seller to
consummate the transactions contemplated in Article 3 of this Agreement is
subject to the satisfaction at or prior to the UPC Closing of the following
conditions:

          (a) Performance.  Each of the material acts and undertakings of
              BancShares to be performed on or prior to the UPC Closing shall
              have been duly performed;

          (b) Representations and Warranties.  The representations and
              warranties of BancShares contained in Article 6 of this Agreement
              shall be true and complete, in all material respects, on and as of
              the UPC Closing with the same effect as though made on and as of
              the UPC Closing;

          (c) Documents. Seller shall have received the following documents and
              instruments:

              (1) A certificate signed by an authorized officer of BancShares
                  dated as of the UPC Closing certifying that:

                                       10
<PAGE>
 
            a.  BancShares' Board of Directors has duly adopted resolutions
                (copies of which shall be attached to such certificate)
                approving the substantive terms of this Agreement and
                authorizing the consummation of the transactions contemplated by
                this Agreement and certifying that such resolutions have not
                been amended or modified and remain in full force and effect;
                and

            b.  Each person executing this Agreement on behalf of BancShares
                is an officer of BancShares holding the office or offices
                specified therein, with full power and authority to execute this
                Agreement and any and all other documents in connection
                herewith, and that the signature of each person set forth on
                such certificate is his or her genuine signature;

          (2) A certificate signed respectively by an authorized officer of
              BancShares stating that the conditions set forth in Section 10.2
              of this Agreement have been fulfilled;

          (3) A certificate signed by each other Seller certifying that the
              person executing this Agreement has full power and authority to
              execute and deliver this Agreement and a certification that the
              warranties and representations of such Seller as set forth in this
              Agreement are true and correct and, in the case of Doty
              Investments and UPC, a certificate signed by an authorized officer
              of each dated as of the UPC Closing certifying that:

              a.  The governing body of Doty Investments has duly adopted a
                  resolution (a copy of which shall be attached to such
                  certificate) approving the substantive terms of this Agreement
                  and authorizing the consummation of the transactions
                  contemplated in this Agreement and certifying that such
                  resolution has not been amended or modified and remains in
                  full force and effect; and

              b.  Each person executing this Agreement on its behalf is an
                  officer (or other authorized person) of the entity holding the
                  office (or offices) specified therein, with full power and
                  authority to execute this Agreement and any and all other
                  documents in connection herewith and that the signature of
                  each person set forth on such certificate is his or her
                  genuine signature.

                                       11
<PAGE>
 
          10.2.  Conditions to Obligations of BancShares to UPC Closing.  Unless
waived in writing by BancShares, the obligation of BancShares to consummate the
transactions contemplated in Article 3 of this Agreement is subject to the
satisfaction at or prior to the UPC Closing of the following conditions:

          (a) Performance.  Each of the material acts and undertakings of
              Sellers to be performed at or before the UPC Closing shall have
              been duly performed;

          (b) Representations and Warranties.  The representations and
              warranties of the Sellers contained in Article 7 of this Agreement
              shall be true and correct, in all material respects, on and as of
              the UPC Closing with the same effect as though made on and as of
              the UPC Closing; and

          (c) Documents.  In addition to the documents described elsewhere in
              this Agreement, BancShares shall have received a certificate
              signed by each Seller certifying that the person executing this
              Agreement has full power and authority to execute and deliver this
              Agreement and a certification that the warranties and
              representations of the Seller as set forth in this Agreement are
              true and correct and, in the case of Doty Investments and UPC:

              (1) A certificate signed by an authorized officer of each dated as
                  of the UPC Closing certifying that:

                  a.  Each person executing this Agreement on its behalf is an
                      officer (or other authorized person) of the entity holding
                      the office or offices specified therein, with full power
                      and authority to execute this Agreement and any and all
                      other documents in connection herewith, and that the
                      signature of each person set forth on such certificate is
                      his or her genuine signature; and

                  b.  In the case of Doty Investments only, that the governing
                      body of Doty Investments has duly adopted resolutions (a
                      copy of which shall be attached to such certificate)
                      approving the substantive terms of this Agreement and
                      authorizing the consummation of the transactions
                      contemplated by this Agreement and certifying that such
                      resolution has not been amended or modified and remains in
                      full force and effect.

          10.3.  Conditions to the Obligations of Sellers to Doty Closing.
Unless waived in writing by a Seller, the obligation of each Seller (other than
UPC and All Saints who will have no

                                       12
<PAGE>
 
participation in any of the transactions contemplated in Article 4) to
consummate the transactions contemplated in Article 4 of this Agreement is
subject to the satisfaction at or prior to the Doty Closing of the following
conditions:

          (a) Performance.  Each of the material acts and undertakings of
              BancShares to be performed on or prior to the Doty Closing shall
              have been duly performed;

          (b) Representations and Warranties.  The representations and
              warranties of BancShares contained in Article 6 of this Agreement
              shall be true and complete, in all material respects, on and as of
              the Doty Closing with the same effect as though made on and as of
              the Doty Closing;

          (c) Documents.  Seller (other than UPC and All Saints) shall have
              received the following documents and instruments:

              (1) A certificate signed by an authorized officer of BancShares
                  dated as of the Doty Closing certifying that:

                  a.  BancShares' Board of Directors has duly adopted
                      resolutions (copies of which shall be attached to such
                      certificate) approving the substantive terms of this
                      Agreement and authorizing the consummation of the
                      transactions contemplated by this Agreement and certifying
                      that such resolutions have not been amended or modified
                      and remain in full force and effect; and

                  b.  Each person executing this Agreement on behalf of
                      BancShares is an officer of BancShares holding the office
                      or offices specified therein, with full power and
                      authority to execute this Agreement and any and all other
                      documents in connection herewith, and that the signature
                      of each person set forth on such certificate is his or her
                      genuine signature;

              (2) A certificate signed respectively by an authorized officer of
                  BancShares stating that the conditions set forth in Article 10
                  of this Agreement have been fulfilled; and

          10.4.  Conditions to Obligations of BancShares to Doty Closing.
Unless waived in writing by BancShares, the obligation of BancShares to
consummate the transactions contemplated in Article 4 of this Agreement is
subject to the satisfaction at or prior to the Doty Closing of the following
conditions:

                                       13
<PAGE>
 
          (a) Performance.  Each of the material acts and undertakings of
              Sellers (other than UPC and All Saints) to be performed at or
              before the Doty Closing shall have been duly performed;

          (b) Representations and Warranties.  The representations and
              warranties of the Sellers (other than UPC and All Saints)
              contained in Article 7 of this Agreement shall be true and
              correct, in all material respects, on and as of the Doty Closing
              with the same effect as though made on and as of the Doty Closing;
              and

          (c) Documents.  In addition to the documents described elsewhere in
              this Agreement, BancShares shall have received a certificate
              signed by each Seller (other than UPC and All Saints) certifying
              that the person executing this Agreement has full power and
              authority to execute and deliver this Agreement and a
              certification that the warranties and representations of the
              Seller as set forth in this Agreement are true and correct and, in
              the case of Doty Investments:

              (1) A certificate signed by an authorized officer of Doty
                  Investments dated as of the Doty Closing certifying that:

                  a.  The governing body has duly adopted a resolution (a copy
                      of which shall be attached to such certificate) approving
                      the substantive terms of this Agreement and authorizing
                      the consummation of the transactions contemplated by this
                      Agreement and certifying that such resolution has not been
                      amended or modified and remains in full force and effect;
                      and

                  b.  Each person executing this Agreement on its behalf is an
                      officer (or authorized person) of Doty Investments holding
                      the office (or offices) specified therein, with full power
                      and authority to execute this Agreement and any and all
                      other documents in connection herewith, and that the
                      signature of each person set forth on such certificate is
                      his or her genuine signature.

          10.5.  Conditions to Obligations of All Parties.  The obligation of
each party to effect each closing contemplated in this Agreement (which is
applicable to such party) shall be subject to the condition that, at the time of
such closing, no claim, action, suit, investigation or other proceeding shall be
pending or threatened before any court or governmental agency which presents a
substantial risk of the restraint or prohibition of the transactions
contemplated by this Agreement or the obtaining of material damages or other
relief in connection therewith.

                                       14
<PAGE>
 
                                  ARTICLE 11.

                                  TERMINATION

          11.1.  Termination.  This Agreement may be terminated at any time
prior to either the UPC Closing or the Doty Closing, as follows:

                 (a) By consent in writing of all parties;

                 (b) By any party adversely affected if the applicable
                     conditions set forth in Article 10 shall not have been
                     satisfied in all material respects (or waived) as of the
                     applicable closing;

                 (c) By any party adversely affected if there shall have been a
                     material breach of any obligation of the other party and
                     such breach shall not have been remedied by the time of the
                     applicable closing after receipt by the breaching party of
                     written notice from another party specifying the nature of
                     such breach and requesting that it be remedied.

          11.2.  Effect of Termination.  If this Agreement should be terminated
prior to the UPC Closing, the obligations of the parties to this Agreement shall
terminate.  If this Agreement should be terminated after the UPC Closing, the
UPC Closing and the transactions contemplated in Article 3 shall not be
affected, but otherwise the obligations of the parties to this Agreement shall
terminate except the provisions of Section 12.1.  A termination under this
Article 11 (whether before or after the UPC Closing) shall not relieve any party
of any liability for a breach of this Agreement or for any misstatement or
misrepresentation, or be deemed to constitute a waiver of any available remedy
for any such breach, misstatement or misrepresentation.

                                  ARTICLE 12.

                               GENERAL PROVISIONS

          12.1.  Notices.  Any notice, request, demand and other communication
which any party may desire or may be required to give shall be in writing and
shall be deemed to be duly given if delivered personally or mailed by certified
or registered mail (postage prepaid, return receipt requested), air courier or
facsimile transmission, addressed or transmitted to such other party as follows:

                                       15
<PAGE>
 
If to BancShares:                Pontotoc BancShares Corp.
                                 19 South Main Street
                                 Post Office Box 29
                                 Pontotoc, Mississippi 38863-0029
                                 Attention:  Mr. Buddy R. Montgomery

If to Bank:                      First National Bank of Pontotoc
                                 19 South Main Street
                                 Post Office Box 29
                                 Pontotoc, Mississippi 38863-0029
                                 Attention:  Mr. Buddy R. Montgomery

In each case,
with a copy to:                  Phelps Dunbar, L.L.P.
                                 Seventh Floor
                                 One Mississippi Plaza
                                 Post Office Box 1220
                                 Tupelo, Mississippi 38802-1220
                                 Attention:  F. M. Bush, III, Esquire

If to Doty Investments:          Doty Investments, L.P.
                                 912 University Avenue
                                 Oxford, Mississippi 38655
                                 Attention:  J. Richard Doty

With a copy to:                  Robert Walker, Esquire
                                 Baker, Donelson, Bearman & Caldwell
                                 165 Madison Avenue
                                 First Tennessee Building, 21st Floor
                                 Memphis, Tennessee 38103

If to Doty:                      Martha W. Doty
                                 2304 Colony Park Drive
                                 Birmingham, Alabama 35234

With a copy to:                  Robert Walker, Esquire
                                 Baker, Donelson, Bearman & Caldwell
                                 165 Madison Avenue
                                 First Tennessee Building, 21st Floor
                                 Memphis, Tennessee 38103

                                       16
<PAGE>
 
If to Jones:                     Gerry G. Jones
                                 C/O Robert Jones, Esquire
                                 1502 Mirror Lake Plaza
                                 2829 Lakeland Drive
                                 Jackson, Mississippi 39208

If to UPC:                       Union Planters Corporation
                                 7130 Goodlett Farms Parkway
                                 Post Office Box 387
                                 Memphis, Tennessee 38147
                                 Attention:  Jackson W. Moore, President

With a copy to:                  Wyatt, Tarrant & Combs, P.L.C.
                                 6075 Poplar Avenue, Suite 650
                                 Post Office Box 775000
                                 Memphis, Tennessee 38177-5000
                                 Attention:  R. Nash Neyland, Esquire

If to All Saints:                ______________________________
                                 ______________________________
                                 ______________________________
                                 Attention:______________________

With a copy to:                  Robert Walker, Esquire
                                 Baker, Donelson, Bearman & Caldwell
                                 165 Madison Avenue
                                 First Tennessee Building, 21st Floor
                                 Memphis, Tennessee 38103

or to such other address as any party may hereafter designate to the other
parties in writing. Notice shall be deemed to have been given on the date
reflected in the proof or evidence of delivery or, if none, on the date actually
received.

          12.2.  Assignability and Successors.  This Agreement shall not be
assignable by any of the parties; provided however, BancShares may assign and
transfer all or any part of its rights and obligations under this Agreement to
any other entity or person, but such assignments shall not relieve BancShares of
its obligations under this Agreement.  This Agreement shall inure to the benefit
of, and be binding upon, the parties and their respective successors and
permitted assigns.

          12.3.  Governing Law.  This Agreement shall be governed by, and
construed and enforced in accordance with, the internal laws, and not the laws
pertaining to choice or conflicts of laws, of the State of Mississippi, unless
and to the extent that federal law controls.

                                       17
<PAGE>
 
          12.4.  Counterparts.  This Agreement may be executed simultaneously in
one or more counterparts, each of which shall be deemed an original, but all of
which shall constitute but one and the same instrument.

          12.5.  Severability.  If any portion or provision of this Agreement
should be determined by a court of competent jurisdiction to be invalid, illegal
or unenforceable in any jurisdiction, such portion or provision shall be
ineffective as to that jurisdiction to the extent of such invalidity, illegality
or unenforceability, without affecting in any way the validity or enforceability
of the remaining portions or provisions of this Agreement.

          12.6.  Modifications, Amendments and Waivers.  At any time prior to
the UPC Closing or the Doty Closing, as the case may be, or the termination of
this Agreement, the parties may, by written agreement:

                 (a) extend the time for performance of any of the obligations
                     or other acts of any other party;

                 (b) waive any inaccuracies in the representations and
                     warranties made to such party by any other party in this
                     Agreement or any other document delivered pursuant to
                     this Agreement;

                 (c) waive compliance with any of the covenants or agreements
                     in favor of such party by any other party in this
                     Agreement; and

                 (d) amend or add to any provision of this Agreement; provided,
                     however, that no provision of this Agreement may be amended
                     or added to except by an agreement in writing signed by
                     each party affected thereby and expressly stating that it
                     is an amendment to this Agreement.

          12.7.  Interpretation.  The headings contained in this Agreement are
for reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

          12.8.  Payment of Expenses.  Except as set forth herein, each party
shall pay its own fees and expenses (including, without limitation, legal fees
and expenses) incurred by each in connection with the transactions contemplated
hereunder.

          12.9.  Finders and Brokers.  The parties represent and warrant to each
other that they have employed no broker, investment banker or finder in
connection with the transactions described in this Agreement under an
arrangement pursuant to which a fee is or may be due to such broker, investment
banker or finder as a result of the execution of this Agreement or the closing
of the transactions contemplated herein.  This section shall survive the
termination of this Agreement.

                                       18
<PAGE>
 
  12.10. Equitable Remedies.  The parties agree that in the event of a
breach of this Agreement, the parties will be without an adequate remedy at law
by reason of the unique nature of the transactions contemplated herein.  In
recognition thereof, in addition to (and not in lieu of ) any remedies at law
which may be available to the parties, the parties shall be entitled to obtain
equitable relief, including the remedies of specific performance and injunction,
in the event of a breach of this Agreement by the other party, and no attempt on
the part of either party to obtain such equitable relief shall be deemed to
constitute an election of remedies by such party which would preclude such party
from obtaining any remedies at law to which it would otherwise be entitled.
Each party covenants that it shall not contend in any such proceeding that the
other party is not entitled to a decree of specific performance by reason of
having an adequate remedy at law.

  12.11. Attorneys' Fees.  If any party shall bring an action at law or in
equity to enforce its rights under this Agreement (including an action based
upon a misrepresentation or the breach of any warranty, covenant, agreement or
obligation, contained herein), the prevailing party in such action shall be
entitled to recover from the other party or parties its reasonable costs and
expenses necessarily incurred in connection with such action (including fees,
disbursements and expenses of attorneys and costs of investigation).

  12.12. No Waiver.  No failure, delay or omission of or by any party in
exercising any right, power or remedy upon any breach or default of any other
party shall impair any such rights, powers or remedies of the party not in
breach or default, nor shall it be construed to be a waiver of any such right,
power or remedy, or an acquiescence in any similar breach or default; nor shall
any waiver of any single breach or default be deemed a waiver of any other
breach or default theretofore or thereafter occurring.  Any waiver, permit,
consent or approval of any kind or character on the part of any party of any
provisions of this Agreement must be in writing and must be executed by the
parties to this Agreement and shall be effective only to the extent specifically
set forth in such writing.

  12.13. Remedies Cumulative.  All remedies provided in this Agreement by
law or otherwise shall be cumulative and not alternative.

  12.14. Bank/Doty Agreement.  Nothing contained in this Agreement shall
affect the parties' obligations under the Bank/Doty Agreement except (i) as
expressly provided above in Article 2, and (ii) the purchase and sale of stock
by a party under this Agreement shall satisfy such parties' obligations under
the Bank/Doty Agreement applicable to such party.

  12.15. Pledge of Agreement.  The parties acknowledge that this Agreement
may be assigned to a commercial lending institution as security for a loan to
BancShares to enable BancShares to consummate the UPC Closing and/or the Doty
Closing.  The parties consent to such assignment.  Such assignment shall not
operate as a release of BancShares or in any way modify the obligations of
BancShares under this Agreement.

                                       19
<PAGE>
 
  12.16. Closing.  It is the intention of all parties that the UPC Closing
and the Doty Closing take place simultaneously on March 18, 1997.

  IN WITNESS WHEREOF, the parties have caused this Agreement to be executed and
delivered as of the date first written above.


                                        PONTOTOC BANCSHARES CORP.


                                        By: /S/ Buddy R. Montgomery
                                            -----------------------------------

                                        Title: President
                                               --------------------------------


                                        FIRST NATIONAL BANK OF PONTOTOC


                                        By: /S/ Buddy R. Montgomery
                                            -----------------------------------

                                        Title: President
                                               ---------


                                        UNION PLANTERS CORPORATION


                                        By: /S/ Original Signed
                                            -----------------------------------

                                        Title: President
                                               --------------------------------

                                        Number of Shares: 264
                                                          ---------------------

                                       20
<PAGE>
 
                                        DOTY INVESTMENTS, L.P.


                                        By: /S/  J. Richard Doty
                                            -----------------------------------

                                        Title:  General Partner
                                                -------------------------------


                                        By: /S/  Martha Anne Doty
                                            ------------------------------------

                                        Title:  General Partner
                                                --------------------------------

                                        Number of Shares: 4,936
                                                          ----------------------


                                        /S/ Martha W. Doty
                                        ---------------------------------------
                                        MARTHA W. DOTY

                                        Number of Shares: 250
                                                          ---------------------

                                        /S/ Gerry G. Jones
                                        ---------------------------------------
                                        GERRY G. JONES

                                        Number of Shares: 1,107
                                                          ---------------------


                                        ALL SAINTS EPISCOPAL CHURCH OF
                                        MEMPHIS, TENNESSEE


                                        By: /S/ Original Signed
                                            -----------------------------------

                                        Title: Treasurer
                                               ---------------------------------

                                       21