USE OF RENEWABLE SUBSTRATES FOR EX VITRO PRODUCTION OF Melaleuca alternifolia CHEEL CLONAL PLANTS BY MINI-CUTTINGS TECHNIQUE

Abstract

The Australian species Melaleuca alternifolia Cheel. has a strong commercial importance due to the extraction of essential oils from its leaves used in the cosmetic and pharmaceutical industry. In order to obtain an efficient plant production system of M. alternifolia the mini-cuttings technique and the clonal mini-garden management in the productivity and rooting of mini-cuttings and different substrate compositions were analyzed during all the seasons. Mini-stumps derived from cuttings and grown in pots (2 L), were submitted to successive harvesting of their sprouts during the four seasons (september/2013 to august/2014). From the mini-stumps sprouts mini-cuttings were produced, wich were were planted in plastic tubes and kept in a greenhouse for 45 days. Six substrates were used for planting the mini-cuttings: commercial substrate (S1); substrate composed of 100% carbonized rice husk (CRH) (S2); substrate composed of 100% coconut fiber (CF) (S3); substrate composed of 50% CF and 50% CRH (S4); substrate composed of 30% CF and 70% CRH (S5); substrate composed of 70% FC and 30% CRH (S6). The high survival of mini-stumps (over 90%) and the mini-cuttings production (282 mini-cuttings.m-2.month-1) in the shade house demonstrate the technical feasibility for the species, being summer the most appropriate time to collect propagules. The substrate composed by 70% CF + 30% CRH (S6) shows superior results for vegetative propagation of M. alternifolia (91.7% of rooted mini-cuttings), as the single one to contemplate simultaneously all parameters. Summer is recommended as the best time for rooting of mini-cuttings.

Effect of Soil Type and In Vitro Proliferation Conditions on Acclimation and Growth of Willow Shoots Micropropagated in Continuous Immersion Bioreactors

“…Micropropagated plants are usually transferred to soilless substrates that provide a root environment that is initially free of plant pathogens and has properties that ensure adequate aeration and water and nutrient supply [ 31 ]. Peat is the most used substrate constituent in horticulture and micropropagation [ 31 , 32 , 33 ]. However, peat is a limited resource that is renewable only over an extremely long time, and the extraction of peat bogs negatively impacts the environment, making it necessary to identify more sustainable alternative solutions [ 31 , 32 , 33 ].…”

“…Peat is the most used substrate constituent in horticulture and micropropagation [ 31 , 32 , 33 ]. However, peat is a limited resource that is renewable only over an extremely long time, and the extraction of peat bogs negatively impacts the environment, making it necessary to identify more sustainable alternative solutions [ 31 , 32 , 33 ]. Some studies have investigated the suitability of using mixtures of peat and renewable materials such as rice husk, as well as products from anaerobic digestion of compost and vineyard pruning [ 33 , 34 , 35 ].…”

Remineralizer and controlled-release fertilizer increase Mimosa scabrella Benth. seedlings growth

“…Among the factors that affect seedlings quality are seeds, substrates, fertilizers, and pesticides (Restrepo et al, 2013). Many studies point to the need for alternative materials in place of those traditionally used, as substrates and fertilizers, looking for greater sustainability in the production chain (Fragoso et al, 2017;Kratz et al, 2017;Stuepp et al, 2017;Gabira et al, 2020aGabira et al, , 2020b. In addition to material choice, the correct management of these resources in the nursery garden ensures better profitability and satisfactory results in the field (Mikula et al, 2020).…”