Influence of weather conditions, on fertility of grape vine winter buds

Abstract

The aim of this investigation was to find out the influences of heat and water precipitations on the potential fertility differentiation, which happens with buds necessary for next pruning, from the middle May until the beginning of July. Investigations which started in 1997. are still carrying out at the Experimental Field of the Institute for Fruit Growing, Viticulture, and Horticulture, Faculty of Agriculture, Novi Sad, which lies in the northern part of Fruska Gora vineyard area, in Sremski Karlovci- Serbia. New designed cultivars Sila, Nova Dinka and Riesling Italian clone SK-13 were examined. By counting the inflorescences on the example of 15 grape vines per variant, coefficients of fertility per cultivar were calculated, and their values per years were compared. By analyzing meteorological factors (heat and water) and coefficients of fertility for the examined period, exceptional connection between them was established. In the years when there was a lot of rain in the May and June, and when they were followed by low temperatures in this period, potential fertility or fertility for the next year, was very low. In some cases it was 50 and more % lower then average values. In the years when temperature conditions, and water precipitations in the May and June were good, next year, coefficients of fertility in all buds were high. To reduce negative influence of bad weather in some years, grapegrowers must help to the grape vine by using all measures of agro and especially phitotechnique. .

Cilj ovog istraživanja je bio da se utvrdi uticaj toplote i padavina na izgradnju moguće rodnosti, koja se u okcima potrebnim za rezidbu, odvija od sredine maja pa do početka jula. Istraživanja koja su počela 1997. su još uvek u toku, na Oglednom Polju Departmana za voćarstvo, vinogradarstvo, hortikulturu i pejzažnu arhitekturu, u Sremskim Karlovcima. Ispitivane su novostvorene sorte sila, nova dinka, grašac beli (ital. rizl.) klon 13, petra i liza. Utvrđivanjem rodnosti na po 15 čokota po varijanti, izračunati su koeficijenti rodnosti, i potom je urađeno njihovo upoređivanje po godinama. Analiziranjem i meteoroloških činilaca i koeficijenata rodnosti u ispitivanom periodu, utvrđena je izuzetna povezanost, ili uslovljenost. U godinama kada je u maju i junu bilo dosta kiše, koje su praćene niskim temperaturama, potencijalna rodnost je bila veoma niska. U pojedinim slučajevima ona je bila 50% i više posto niža nego prosečna. U godinama kada su toplotni uslovi i količina padavina u maju i junu bili povoljni, koeficijenti rodnosti su bili visoki. Da bi se sprečio negativan uticaj lošeg vremena u pojedinim godinama, vinogradari moraju pomoći vinovoj lozi posebnim agro i fitotehničkim merama. .