The study was conducted during the period 2017-2019 in the experimental base of the Department of Fruit Growing at the Agricultural University – Plovdiv. At the beginning of the experiment the plants of two varieties of goji berry (JB 1 and JB 2). were in the fifth vegetation. They are formed like trees with a stem height of 70 cm, leader branch, with seven fruiting shoulders and a supporting structure.
The aim of the study is to trace the influence of different strength of pruning (winter) on the vegetative growth and fruiting of the studied varieties. For each variety, two variants of pruning were tested, respectively strong and weak.
At the beginning of the experiment in the variant with strong pruning, the fruiting shoulders were shortened to 10 cm in length, and the shoots from the previous year on them were shortened to 5 cm each year. In the variant with weak pruning, the fruiting shoulders were left with a length of 30 cm, and the branches from the previous year on them are shortened to 10 cm each year.
The observed indicators were: stem diameter, crown diameter, crown volume, mass of the cut wood, yield and mass of the fruit.
It was not found influence of the strength of the pruning on the vegetative and reproductive manifestations of the trees. The average yield of fresh fruit (kg/tree) in the tested pruning variants from JB 1 is from 1.19 kg to 1.29 kg, respectively for strong and weak pruning and for JB2 for the same pruning options 0.89 kg and 0.88 kg.
In the conditions of the experiment it was established that in both varieties the tested variants of pruning do not lead to significant difference in fruit yield and vegetative growth.
Keywords: Lycium barbarum L., pruning, growth, productivity