Abstract. Effect of plant samples collection date on nutrients leaf content and nutrient plant status of four species of highbush blueberries (‘Bluecrop’, ‘Croatan’, ‘Darrow’ and ‘Heerma’) were studied. The plant material was sampled two dates: date I on the turn of June and July and date II at the beginning of August. The date of collection of plant samples affected significantly the content of N, P, Mg and Zn in leaves of highbush blueberry. The analysis of leaves sampled in the first term proved optimum status of nutrition of plant with K, Zn, Mn and Fe. The content of N, P, Mg, Ca and Cu was below the range assumed as optimum. The nutritional status of plant determined at the beginning of August was optimum for macronutrients (with exception of P) and all micronutrients. The significant differences between cultivars with regard to dry matter, K, Mg, Ca and Mn content in leaves of highbush blueberry were proved.

The effect of plant samples collection date on nutrients
leaf content of four species of highbush bluberry
(Vaccinium corymbosum L.)

Summary

The study was carried out in 2004 and 2006 on an experimental field in Garlica Murowana near Cracow founded in 1989 on brown soil developed from loess. This soil is characterized by texture of loamy silt, medium organic matter content and high content of P, K and Mg. The bushes of four cultivars of high-bush blueberry (‘Bluecrop’, ‘Croatan’, ‘Darrow’ and ‘Heerma’) were planted in spacing 2 × 1.5 m. The plantation was mulched with sawdust and fertilized with ammonium sulphate in dose 50 kg·ha^-1 every year in spring. The plant material was sampled on two dates: date I on the turn of June and July and date II at the beginning of August. The leaves collected from non-fructifying shoots (4-6th from apex) were used as indicators of nutritional status of plant. The date of collection of plant samples affected significantly the content of N, P, Mg and Zn in leaves of highbush blueberry. The analysis of leaves sampled in the first term proved optimum status of nutrition of plant with K, Zn, Mn and Fe. The content of N, P, Mg, Ca and Cu was below the range assumed as optimum. The nutritional status of plant determined at the beginning of August was optimum for macronutrients (with exception of P) and all micronutrients. The significant differences between cultivars with regard to dry matter, K, Mg, Ca and Mn content in leaves of highbush blueberry were proved.