<b>Roots of ‘BRS Princesa’ banana fertigated with humic substances and saponin-based plant extracts

Abstract

ABSTRACT. This study aimed to evaluate the effects of fertigation with humic substances, with and without the addition of plant extracts, on the root system of the 'BRS Princesa' banana cultivar. The banana crop was cultivated at a spacing of 2.0 x 2.5 m and fertigated using a drip system in a dystrocohesive Yellow Latosol. The experimental design was randomized blocks, in a split-split-plot scheme with five replicates, for the following factors: humic substance doses and presence of a plant extract formulation. The treatments consisted of five doses of humic substances, based on a reference dose of 14.14 L ha , in the presence and absence of plant extract. The variable root length (cm) was subjected to variance analyses to evaluate the effect of the humic substances, either isolated or in interaction with plant extract and soil depth. The use of the plant extract increased the effect of the humic substance on root length but overshadowed its effect for the different doses of humic substance. Root length was not sensitive to increasing humic substance dose with plant extract for doses of up to 42.42 L ha -1 at 0 -0.40 m depth.

Agronomic performance and soil chemical attributes in a banana tree orchard fertigated with humic substances1

“…The absence of positive effects from the humic substances fertigation on the soil chemical attributes may explain the lack of significant effects on the growth and yield properties of the orchard. This corroborates the findings by Coelho et al (2016), who reported similar results for the agronomic performance of the 'BRS Princesa', during its first production cycle. The average values reported for the biometric variables are presented in Table 6.…”

“…Coelho et al (2016) studied the drip irrigation of humic substances (doses up to 42.42 L ha -1 cycle -1 ), in a Dystric Densic Xantic Ferralsol cultivated with 'BRS Princesa' banana trees, and found no effects on the plant performance or soil physical-hydraulic attributes, during the first production cycle of the orchard.…”

Fertigation of ‘BRS Princesa’ banana with humic substance and saponin-based plant extracts

“…The absence of effects on banana growth can be related to the response time of the soil to the application of HS, which acted as conditioners of soil chemical and physical quality, improving its capacity of ion exchange, availability of nutrients, and structure (Selim and Mosa, 2012;Coelho et al 2016), but without directly supplying nutrients, such as organic matter in less advanced stages of decomposition, so that their action on plant nutrition and growth is indirect and does not occur immediately. Therefore, their effects may take a longer time in comparison with fertilizers industrially produced for rapid incorporation of nutrients …”

“…Besides, the nature of these organic compounds is relatively complex and there is unconsolidated knowledge on the action of the humic fraction on plants due to its composition and chemical structure, which has not been elucidated and is variable (Baldotto and Baldotto, 2014). Another aspect is the doses of HS application, which may not have been sufficient to promote positive responses on banana plants (Hartz and Bottoms, 2010;Lodhi et al, 2013;Coelho et al, 2016;Melo et al, 2016).…”

Cultivo Orgânico Da Bananeira ‘Brs Tropical’ Sob Irrigação E Uso De Cobertura Orgânica No Solo

“…Em sinergia, a aplicação dos resíduos vegetais pode ajudar a proteger o solo, atenuar o crescimento de ervas invasoras, conservar água na rizosfera, potencializar a atividade biológica no solo, melhorar a ciclagem de nutrientes, com melhoria da fertilidade do solo no tempo (RESENDE et al, 2005;BORGES et al, 2015;COELHO et al, 2016).…”