Biomass distribution efficiency of rose cv. Charlotte grown in soil and substrates at second production peak

Growing plants in substrates is an alternative for the production

of roses under unfavorable soil conditions. The objective of this

study was to determine the biomass distribution efficiency of

rose cv. Charlotte grown in soil and substrates under greenhouse

conditions until second production peak. In this trial,

soil and substrates with 100% burned rice husk (100BRH); 65%

burned rice husk: 35% coconut fiber (65BRH); 35% burned

rice husk: 65% coconut fiber (35BRH); and 100% coconut

fiber (100CF) were used. The experimental design consisted

of a randomized complete block design with three repetitions.

Destructive sampling was carried out using whole plants and

flowering stems at previously determined bud stages. Leaf area

and dry matter in organs were measured and growth rate and

physiological indexes were calculated. The assessed variables

were fitted to logistic and exponential models. The plants grown

in substrates with BRH (burned rice husk) showed similar

values regarding dry matter and fresh weight accumulation

in organs. Plants in the soil treatment were the last ones to

reach the different development stages of the flowering buds,

while those that were grown in 100CF were the first ones. The

treatments 35BRH and 100CF showed less growth of flowering

stems, which was expressed in terms of relative dry matter

increase per day. The plants grown in soil showed more dry

matter in leaves and stems but less in flower buds. The 65BRH

treatment showed some of the highest dry matter accumulations

in leaves, stems and flower buds and also showed the highest

leaf area ratio, leaf weight ratio, and specific leaf area values.