Effect of some pre-harvest treatments on yield, fruit quality and storageability of some grape cvs

Abstract

This work invol ved t wo parts. The first one was ca r r i ed o ut to s tud y the effect of GA3 treatme nts on y i e ld and fruit quality of Th ompson seedless a nd Flame seed l ess g rapes during 1 995 and 1 996 seaso ns. The obta ined res ults for t he l wo s tudied cvs. showed that GA3 trea tm e nts for e l o nga t ion , thinning and si zing had increased tota l y i e l d, c lus tuer wei g ht, weight of 100 be rries, bunch width and l ength , berry w id th and length, torus thickness, berry shu ttering %, beny juice% and anthocyanine (In Flame seedless) . On the other hand, GA3 trea tments im poroved clus ter compactness, decreased s hot berries%, be rry firmness, seed traces%, berry ad h e ren ce strength and shelf life in d ays. Mea n w hil e, T. S.S, acid i t y and T.S.S/acid ratio were not affected by GA:1 trea tm e nts.

The second part of this stud y was des igned to examine 0 s torageaqilit y at 0 C of the previ ons GA3 treated bunches g rapes of both Thom pso n and Flam e seedless grapes. Th e obtained res ults showed th at GA3-treated c lusters stored for a time shorte r than untreated ones d ue to th e highe r in crease in decay %. GA 3 treatm e nts recorded the hig hest va lues of decay%, tours thickness, berry firmmess , berry ad he rence strength, berry shuttering% and be rry jui ce. On contrary, a n evident decrease in weight loss% and she lf-!ife were n ot iced in GA3 - treated clusters . No clear effects on T.S.S , acidty and T.S.S/acid ratios were noticed .