FERTIGATION OF HIGHBUSH BLEUEBERRY (Vaccinium corymbosum L.). PART III. THE EFFECT ON NUTRIENT CONTENTS IN LEAVES

Fertigation with the nutrient solutions containing macro and microelements could influence on the nutrient status of highbush blueberry. Studies were conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. The aim was to analyze the effect of fertigation using 3 nutrient solutions (F-1, F-2, F-3) in comparison to drip irrigation (F-0) on the contents of macro- and microelements as well as sodium and aluminium in leaves. Fertigation with nutrient solutions F-1, F-2 and F-3 in relation to drip irrigation (F-0) increased the contents of nitrogen, potassium and calcium in the leaves of highbush blueberry cv. ‘Bluecrop’ at both terms of leaves collection (15.06 and 15.07) while it reduced the content of magnesium with the application of nutrient solutions F-2 and F-3 at the second term of study. No distinct effect of fertigation on the contents of phosphorus and sulphur in leaves was found. Among microelements the greatest effect of fertigation was indicated for boron. Nutrient solutions F-2 and F-3 at the first term as well as F-1, F-2 and F-3 at the second one increased boron content in leaves. Fertigation was found to have an effect on the increase of manganese and copper contents at the term II and zinc at the term I. No variation was recorded in iron content in leaves under the influence of fertigation. Fertigation reduced the content of aluminium in leaves of highbush blueberry. The effect was shown mainly under the influence of the application of nutrient solution F-2. Contents of N, P, K, Zn, Na and B decreased but Ca, Mg, Fe, Mn and Al increased in leaves between the first (15.06) and second II (15.07) term of study. No changes were found in contents of S or Cu in leaves of highbush blueberry at both sampling terms. For the evaluation of highbush blueberry nutrition status in Poland the term II seems to be more advantageous. It is the second half of July, after the first harvest of cv. „Bluecrop”. In this period there is the stabilization of vegetative growth with marked effects of bushes yielding.