CHANGES IN YIELD PARAMETERS AND POLYPHENOL CONTENT IN RESPONSE TO DIFFERENT PLANT SPACING IN EDIBLE HIBISCUS PRODUCTION

The aim of the study was to verify the effect of plant spacing on the yield parameters and quality of edible hibiscus fruits, known as okra. The results were compared with other authors who studied the connections between plant spacing and other production parameters. Two varieties ('Baby bubba ́ and ́Clemson spineless ́) and different spacing effect (S1 = 0.6 x 0.45m; S2 = 0.5 x 0.45m; S3 = 0.6 x 0.3m; S4 = 0.5 x 0.3 m) on average fruit weight, yield per plant, yield per hectare and content of total polyphenols were tested in work. The average fruit weight of cultivar ́Baby bubba ́ variety was ranged from 25.7 g (S1) to 28.7 g (S2). The yield per plant was ranged from 308.2 g (S1) to 345.0 g (S2). The yield per hectare was showed by significantly different results; the highest okra yield was found in the variant of spacing S4 (21.1 t.ha-1) and the lowest yield was found in the spacing variant S1 (11.3 t.ha- 1). The content of total polyphenols in okra fruits was significantly highest in S1 spacing (16519.6 mg GAE.kg-1 DM), compared to other spacing variants. In ́Clemson spineless ́ okra cultivars, slightly different results were found. The average fruit weight of okra was ranged from 19.2 g (S4) to 25.8 g (S2). The yield per plant was ranged from 230.9 g (S4) to 309.3 g (S2). The effect of plant spacing in this cultivar was similar to results of yield in the cultivar ́Baby bubba ́. The yield per hectare was ranged from S1 (10.8 t.ha-1) to S4 variant (15.3 t.ha-1). The highest content of polyphenols was also found in the spacing S1 (17694.8 mg GAE.kg-1 DM). Obtained results showed on the significant effect of plant spacing and grown cultivar on the yield parameters and polyphenol content. Results can be usable for potential growers of okra in conditions of Slovak Republic, or Middle-Europe generally.