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                             LOAN MODIFICATION AGREEMENT

    This Loan Modification Agreement is entered into as of July 5, 1996, by and
between Agro Dynamics, Inc. ("Agro Dynamics") and Agro Dyanmics Canada Inc.
("Agro Canada") (each, a "Borrower" and collectively, the "Borrowers") and
Silicon Valley Bank, a California-chartered bank  ("Lender"), with its principal
place of business at 3003 Tasman Drive, Santa Clara, CA 95054 and with a loan
production office located at Wellesley Office Park, 40 William Street, Suite
350, Wellesley, MA 02181, doing business under the name of "Silicon Valley
East."

1.  DESCRIPTION OF EXISTING INDEBTEDNESS:  Among other indebtedness which may
be owing by Borrowers to Lender, Borrower's are indebted to Lender pursuant to,
among other documents, a Revolving Credit Note, dated October 28, 1994 in the
original principal amount of up to One Million Five Hundred Thousand and 00/100
Dollars ($1,500,000.00) (the "Revolving Note").  The Revolving Note has been
modified pursuant to Loan Modification Agreement dated October 5, 1995.  The
Revolving Note, together with other promissory notes from Borrowers to Lender,
is governed by the terms of a Loan Agreement, dated October 28, 1994, between
Borrowers and Lender, as such agreement may be amended from time to time (the
"Loan Agreement").

Hereinafter, all indebtedness owing by Borrowers to Lender shall be referred to
as the "Indebtedness."

2.  DESCRIPTION OF COLLATERAL:  Repayment of the indebtedness is secured by
three Security Agreements, each, dated October 28, 1994 (each, the "Security
Agreement"), executed by Agro Dynamics and Agro Canada and EcoScience
Corporation (the "Pledgor"); two Stock Pledge Agreements, each dated October 28,
1994 (each, the "Pledge Agreement"), one executed by Pledgor and one executed by
Agro Dynamics and an Assignment of Deposit Account dated October 5, 1995 (the
"Assignment"), executed by Pledgor.  Additionally, repayment of the Indebtedness
is guaranteed by EcoScience Corporation (the "Guarantor") pursuant to an
EcoScience Guaranty dated October 28, 1994 (the "Guaranty").

Hereinafter, the above-described security documents, together with all other
documents securing payment of the Indebtedness shall be referred to as the
"Security Documents."  Hereinafter, the Security Documents, together with all
other documents evidencing or securing the Indebtedness shall be referred to as
the "Existing Loan Documents."

3.  DESCRIPTION OF CHANGE IN TERMS.

    A.   MODIFICATION(S) TO REVOLVING NOTE.

1.  Payable in one payment of all outstanding principal plus all accrued unpaid 
interest on September 5, 1996.  In addition, Borrowers will pay one regular 
monthly payment of all accrued unpaid interest due on August 5, 1996.

4.  PAYMENT OF LOAN FEE.  Borrowers shall pay Lender a fee in the amount of One
Thousand and 00/100 Dollars ($1,000.00) (the "Loan Fee") plus all out-of-pocket
expenses.


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5.  CONSISTENT CHANGES.  The Existing Loan Documents are hereby amended
wherever necessary to reflect the changes described above.

6.  NO DEFENSES OF BORROWER.  Each Borrower agrees that, as of this date, it
has no defenses against the obligations to pay any amounts under the
Indebtedness.

7.  CONTINUING VALIDITY.  Borrowers understand and agree that in modifying the
existing Indebtedness, Lender is relying upon Borrowers' representations,
warranties, and agreements, as set forth in the Existing Loan Documents.  Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect. 
Lender's agreement to modifications to the existing Indebtedness pursuant to
this Loan Modification Agreement in no way shall obligate Lender to make any
future modifications to the Indebtedness.  Nothing in this Loan Modification
Agreement shall constitute a satisfaction of the Indebtedness.  It is the
intention of Lender and Borrowers to retain as liable parties all makers and
endorsers of Existing Loan Documents, unless the partly is expressly released by
Lender in writing.  No maker, endorser, or guarantor will be released by virtue
of this Loan Modification Agreement.  The terms of this Paragraph apply not only
to this Loan Modification Agreement, but also to all subsequent loan
modification agreements.

8.  JURISDICTION/VENUE.  Each Borrower accepts for itself and in connection
with its properties, unconditionally, the non-exclusive jurisdiction of any
state or federal court of competent jurisdiction in the Commonwealth of
Massachusetts in any action, suit or proceeding of any kind against it which
arises out of or by reason of this Loan Modification Agreement, provided,
however, that if for any reason Lender cannot avail itself of the courts of the
Commonwealth of Massachusetts, then venue shall lie in Santa Clara County,
California.

9.  COUNTERSIGNATURE.  This Loan Modification Agreement shall become effective
only when it shall have been executed by Borrowers and Lender (provided,
however, in no event shall this Loan Modification Agreement become effective
until signed by an officer of Lender in California).

10. CONDITIONS.  The effectiveness of this Loan Modification Agreement is
conditioned upon payment of the Loan Fee.

    This Loan Modification Agreement is executed as of the date first written
above.


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BORROWERS:                             LENDER:

AGRO DYNAMICS, INC.                    SILICON VALLEY BANK, doing
                                       business as SILICON VALLEY EAST

By:  /s/ Harold A. Joannidi            By:  /s/ Joan S. Parsons        
   --------------------------              -----------------------------
Name:  Harold A. Joannidi              Name:  Joan S. Parsons        
     ------------------------                ---------------------------
Title:   Treasurer                     Title: Senior Vice President      
      -----------------------                 --------------------------

By:  /s/ Michael DeGiglio    
   --------------------------
Name:  Michael DeGiglio    
     ------------------------
Title:   President           
     -----------------------

AGRO DYNAMICS CANADA INC.              SILICON VALLEY BANK

By:  /s/ Harold A. Joannidi            By:  /s/ Christine Ware        
   --------------------------             -----------------------------
Name:  Harold A. Joannidi              Name:  Christine Ware        
     ------------------------               ---------------------------
Title:   Treasurer                     Title:  Vice President          
     -----------------------                  -------------------------
                                       Signed at San Jose, CA
By:  /s/ Michael DeGiglio    
   --------------------------
Name:  Michael DeGiglio    
     ------------------------
Title:   President           
     -----------------------

The undersigned hereby consents and confirms the modifications to the
Indebtedness pursuant to this Loan Modification Agreement and the Existing Loan
Documents (including such provisions which apply specifically to EcoScience),
hereby ratifies all the provisions of the Guaranty, Security Agreement, Pledge
Agreement and Assignment, and confirms that all provisions of those document are
in full force and effect.

GUARANTOR/PLEDGOR:

ECOSCIENCE CORPORATION

By:  /s/ Harold A. Joannidi     
   --------------------------
Name:  Harold A. Joannidi     
     ------------------------
Title:   Treasurer            
     -----------------------


By:  /s/ Michael DeGiglio    
   --------------------------
Name:  Michael DeGiglio    
     ------------------------
Title:   President           
      -----------------------