Sustainable organic substrate production using millicompost in combination with different plant residues for the cultivation of Passiflora edulis seedlings

The use of sustainable organic substrates of recognized quality is essential in the production of seedlings of fruit species. In this context, the present study aimed to formulate different sustainable organic substrates based on millicompost combined with different proportions of locally available organic waste, such as coconut fiber (Cocos nucifera) powder, gliricidia (Gliricidia sepium) and elephant grass shavings (Pennisetum purpureum) for the production of Passiflora edulis seedlings. The organic substrates used were as follows: S1- millicompost; S2- commercial substrate and substrates formulated based on millicompost: S3%–25% millicompost + 25% gliricidia + 25% elephant grass + 25% coconut fiber; S4%–50% millicompost+ 50% elephant grass; (S5) 50% millicompost+ 50% gliricidia; (S6) 50% millicompost+ 50% coconut fiber. At 56 days of sowing, the following morphological parameters were evaluated: shoot dry mass (SDM); root dry mass (RDM); plant height (PH); number of leaves (NL); stalk diameter (SD); root volume (RV); leaf area in cm 2 (LA); seedling vigor (SV) and clod stability (CS). The nutrient contents (N, P, K, Ca and Mg) accumulated in the shoot dry mass of the seedlings were determined after this period. The organic substrates that provided seedlings with significantly higher parameters (P S6> S5. The other substrates (S2, S3 and S4) presented seedlings with morphological parameters similar to each other. In addition, there was a greater accumulation of P, K Ca and Mg (P S6> S5. The substrates S6 and S5 represent two new options of sustainable substrates, being effective in the production of yellow passion fruit seedlings with excellent vegetative growth rates. [Display omitted] •Millipedes are able to transform agricultural and urban waste into organic compost.•The use of millicompost in the cultivation of Passiflora edulis seedlings was evaluated for the first time.•The millicompost is efficient and has produced healthy and vigorous seedlings.•Organic substrates based on millicompost with powdered coconut fiber or gliricidia are efficient.•New organic substrate options for passion fruit seedling producers are available.