Perishable goods

hello friends i have a query one of my clients sells vegetables in wholesale after one month they make payment for same . if its 500000 sale the purchase says due to low quality/ damages in transportation we will be paying only 4.50laks etc etc . now how to show the same for accounting purpose ? we cant treat as sales return as goods are not actually returned , only sales amount is reduced . can we show as normal losses due to perishable items ?or show it as cash discounts at the time of payment ? please help