Baby leaf lettuce production in trays with reused and solarized substrate

Abstract

Concerning the baby leaf production in trays, substrate can be reused for a certain number of times depending on its chemical and physical characteristics, but populations of pathogens such as Pythium aphanidermatum and Rhizoctonia solani that can cause damping off of lettuce, can build up during the reuse of this substrate. Solar treatment in a solar collector can be an alternative for the disinfestation of these substrates. Thus, the objective of this research was to study the reuse of coconut fiber substrate and its solar treatment in solar collector on baby leaf lettuce production. The experimental design was randomized blocks, in a factorial scheme 4 (first-use substrate, reused once, reused twice and reused three times) x 2 (with and without solar treatment), with four replications. The substrate reused 3 times provided the highest yield, 7.4 kg/m2, 14.8 cm plant height, 7.8 leaves, length and width of the largest leaf 13.9 and 4.8 cm, respectively; 3.4 and 0.21 g/plant fresh and dry mass, respectively; pH 6.8, 0.34 and 0.35 dS/m electrical conductivity, 25.1 and 30.2 mg/L NH4 + and 16.8 and 14.6 mg/L NO3 -, dry density 169 and 177 kg/m3 and water holding capacity 53 and 57% for substrates with and without solar treatment, respectively. There was an increase in the population of P. aphanidermatum, but the solar treatment was effective to eliminate this pathogen, and R. solani was not detected in the substrates. This study showed that the reuse of a coconut fiber substrate for one to three times could enhance the yield of lettuce baby leaf and promote the chemical and physical characteristics of the substrate.

Seed potato minitubers production in a reused substrate

“…Cardoso et al (2010) observed a decrease in the percentage of aeration space and a consequent increase in water availability to melon plants cultivated in the reused substrate, but like the present study, productivity was not affected by reuse. Moraes et al (2016) and Purquerio et al (2016) also highlighted the advantage of reused coconut substrates over the first-use substrate in the lettuce baby leaf production without any productivity losses.…”

Influência de substratos no cultivo de pimenta biquinho em sistema semi-hidropônico.

“…Esse substrato de origem vegetal natural, além de renovável é bastante leve. Oferta diversos benefícios como durabilidade extensa sem alteração de suas características físicas, ausência de patógenos, baixo custo para o produtor quando comparado a outros substratos e ainda a possibilidade de esterilização (MORAES et al, 2016).…”