The effect of shoot training on yield, fruit quality and leaf chemical composition of eggplant in greenhouse cultivation

The aim of the investigations was to determine the best method of eggplant (Solanum melongena L.) pruning in greenhouse production. The investigations were carried out in 1999 - 2001 in the experimental greenhouse of the University of Agriculture in Krakow, Poland. The ‘Tania F1’ hybrid was used in the early spring-summer production in a heated greenhouse. Plants were pruned to one or two shoots. In the case of two-shoot plants, the second shoot was led out from the first, third, sixth and ninth node. The intense pruning positively affected the PAR conditions in the plant profile. The most effective fruit setting was observed in the intensely pruned plants. The greatest number of fruits was set at the lowest nodes. Pruning affected the total but not marketable yield of fruits. Two-shoot plants with the second shoot led out from the sixth node produced the greatest fruits, both in early and total yield. A high level of reducing sugar was found in the fruits of moderately pruned plants. Fruits of two-shoot plants with the second shoot led out from the sixth node and pruned to one shoot contained the greatest level of L-ascorbic acid. The greatest levels of reducing sugar and starch were found in the leaves of moderately pruned plants, having the best PAR conditions. The method of pruning slightly affected the level of pigments in the eggplant leaves.