PASSIFLORA CAERULEA L. TREATED WITH TRICHODERMA PLANT BIOSTIMULANTS CONSORTIUM. MORPHO-ANATOMICAL CONSIDERATIONS

Abstract

Plant biostimulants are an emerging category of inputs into technologies for plant cultivation, which activate plant metabolism and nutrient use efficiency. A microbial plant biostimulants consortium was applied on Passiflora caerulea L., a medicinal and nutraceutical plant grown in greenhouse conditions. The treatments were applied during P. caerulea vegetation, as a foliar treatment with a Trichoderma consortium suspension of 10 cfu/ml, equiv. to 10 spores/ha. The treatment determined significant quantitative changes on morpho-anatomical features, on the leaf lamina (lamina with 10-20% thicker, palisadic cells with 10-20% longer, larger stomata and stomatal index increased by 15%), on the leaf petiole (the diameter ~30% larger, conducting bundles, 20% more developed, the adaxial conducting bundles, ~30% increase) and on the stem (the diameter with 15-20% larger, central cylinder with 1520% bigger, xylem vessels of more than 50 μm diameter, with 20% more present). These morphoanatomical features demonstrate the plant biostimulants effects of Trichoderma consortium. The results presented here sustain with morpho-anatomical data the accumulation the bioactive compounds, mainly polyphenols and flavonoids with an increased antioxidant activity, which we already reported. Larger stems and leaves of P. caerulea, allow accumulation at a higher level of bioactives compounds.