Research on growth dynamics of fruit, shoots and mineral elements in olive leaves in ecological conditions of Istria

Istraživana je dinamika rasta mladice, ploda i biogenih elemenata tijekom razdoblja vegetacije u lišću na četiri godine starim stablima maslina sorti Leccino i Picholine. Masline su uzgojene na crvenici u masliniku Červar kraj Poreča. Istraživanjima je ustanovljeno da rast mladice slijedi izduženu sigmoidnu krivulju. Intenzivan rast mladice odvija se do kraja kolovoza a potpuno završava krajem rujna. Obje sorte postigle su dobar prosječan prirast jednogodišnjih izbojaka. Rast ploda slijedi dvostruku izduženu sigmoidnu krivulju. Najveći je i jednoličan u prvoj i drugoj fazi rasta do 15 rujna kada postigne 50% od volumena u vrijeme dozrelosti. Od 1. do 15. listopada rast je usporen kada dolazi do odrvenjavanja endokarpa, nakon čega je opet intenzivan i jednoličan. Vjerojatno jednoličnom rastu ploda u vrijeme najvećeg nakupljanja ulja, pored ostalog, treba pripisati visoku kvalitetu maslinova ulja u Istri. Naime, uz takav rast postupno se u plodu nakupljaju hranjiva, a posebice ulje i njegovi sastojci. Dinamika biogenih elemenata pokazuje da se koncentracija dušika i kalcija od početka do kraja vegetacije postupno povećava dok koncentracija kalija opada. Koncentracija fosfora, magnezija i bora u lišću obiju sorti je jednolična tijekom vegetacije. Opskrbljenost dušikom, fosforom, kalijem, kalcijem i borom je dobra a magnezijem slaba do umjerena.Research on the growth dynamics of shoots, fruit and mineral elements in leaves during vegetation was carried out on four year old olive trees of the Leccino and Picholine varieties. The trees were grown in red soil in the olive grove Červar near Poreč. It was established that the shoot growth followed an elongated sigmoidal curve. The intensive shoot growth continued to the end of August and comp¬letely finished at the end of September. Both varieties achieved good average growth of one year old shoots. The fruit growth followed a double elongated sigmoidal curve. It was the biggest and uniform in the first and second phase of growth until September 15, when 50% of the mature volume was achieved. From October 1 to 15 the growth slowed down when the endocarp lignified after which the growth was intensive and uniform. The high quality of olive oil in Istria should probably, among others, be attributed to uniform fruit growth in the time of most intensive oil accumulation. With such growth nutrients, particularly oil and its ingredients, gradually accumulate in the fruit. The dynamics of mineral elements shows that the concentration of nitrogen and calcium gradually increases from the beginning to the end of vegetation while that of potassium falls. The concentration of phosphorus, magnesium and boron in the leaves of both varieties is uniform, during vegetation. The supply of nitrogen, phosphorus, potassium, calcium and boron is good while that of magnesium is poor to moderate