Induction of rooting in fig tree cuttings due to the use of coconut water as a root growth promoter

Abstract

Ficus carica L. is compatible with Brazil’s soil and climatic conditions, making the country its largest producer in Latin America. Brazilian fig cultivation utilizes cutting propagation for plant multiplication; the Roxo de Valinhos cultivar is the most widely cultivated. Other fig accessions also have market value, such as the Turco cultivar, which is generally used as a rootstock. Vigorous seedlings are necessary for good fruit production; they can be obtained using growth regulators, such as indolebutyric acid (IBA; the most commonly used regulator in fruit production), to enhance rhizogenesis. However, natural products, such as coconut water (rich in auxins), are also viable for this purpose. In this study, we aimed to determine the most advantageous rooting stimulator for ‘Turco’ fig cuttings and verify whether the product used is related to the type of fig accession. Two consecutive experiments were conducted using a randomized block design. The first experiment included three treatments: powdered IBA; coconut water; and IBA solution at 6,000 mg L⁻¹, conducted in the municipality of Dracena, SP; this was conducted to identify the best rooting agent to be used in the second experiment. The second experiment included eight treatments: accession 33; accession 34; accession 35; accession 47; accession 40; accession 41; accession 42; and accession 45, conducted in the municipality of Ilha Solteira, SP. Both experiments were conducted in a greenhouse with intermittent misting for 40 days. At the end of each experiment, the percentage of rooting, number of sprouts, length of the longest sprout, fresh and dry mass of the shoots and roots, and relative growth rate (RGR; obtained by measuring the cuttings’ sprouts at 10-day intervals) were analyzed. Data were subjected to statistical analysis in SISVAR using Tukey’s test at p ≤ 0.05; RGR data were adjusted using second-order polynomial regressions. The first experiment demonstrated that the use of coconut water resulted in 100% root growth for ‘Turco’ fig. The second experiment demonstrated that the utilization of coconut water depends on fig accession; results differ for each treatment, with accession 45 (‘Turco’) obtaining the best results. The other accessions obtained promising results, except for accession 33 and 41. Hence, coconut water is considered an effective rooting stimulator for fig cultivation.