ÖZETBu çalışma, 1971-1973 yıllarında Atatürk Üniversitesi Zi·raat Fakültesi Bağ-Bahçe Kürsüsünde yapilmıştır. Araştırmanıngayesi: hasat önü püskürmesi şeklinde 5 patates çeşidinintoprak üstü aksamına atılan 2500 ppm. konsantrasyondakiMH-30 u.n mahsul verimine; 6.5 aylık muhafaza peryodu sonunda sürgün verme, çürüme ve toplam kayba olanetkileri ile özgül ağırlık ve kuru madde miktarına tesirini incelemektir.Effect of Maleic Hydrazzide (MH-30) on Yield and Storage Losses of Five Potatoe CultivarsIn order to determine theeffeets of maleie hydrazide on yieldand stOl-age losses of potatae va·rieties, field and storage experimentswere initiated in 1971-1973.PIants were grown on the AgriculturaıExperiment Station VegetableCrops Researeh area at Erzu·rum, Tu~key. Both field and storageexperiments, the experimentaldesign was split-plot arrangement.Maleie hydrazide was appIied topotatae vines in the field at can·centratian 2500 ppm, 47-60 daysbefore harvest.Potatoes were stored at a eontrolledstarage room. Starage temperaturewas 4.5 - 5°e and relativehumidity wasn't controlled.p.ereentage total weight lass,sprouting and rotting were reeordedat the end of 6.5 months storageperiod. Dry matter eontentand the speeifie gravity of the tuberswere alsa determined.Analysis of variance of datawas eondueted. The Least SignifieantDifferenee test Was used totest for significant differeneesaınong means.The fdJllowing results ~reobtained :ı. Yields dec1ined by MH-30appIieation.2. Pereentage weight lost bysprouting and pereentage totalstorage losses were signifieandy 10weredby MIL treatment.3. Pereentage weight lost byrotting was different among eultivarsand treatments.4. The effeet' of MH-30 onspecifie gravity and dry matterconterit of tuberswere differentdepending upon year and euhivars.