Growth analysis of lettuce under different substrate compositions
- Lactuca sativa L.,
- leaf area,
- solar radiation,
The objective of this work was to evaluate lettuce growth in greenhouse
under different types of substrates. The experiment was conducted in a
greenhouse, under randomized block design, with six treatments and three replicates. The compositions of the substrates were: T1= 100% organic compound; T2= 75% organic compound plus 25% substrate Plantmax®; T3= 50% organic compound plus 50% substrate Plantmax®; T4= 25% organic compound plus 75% substrate Plantmax®; T5= 100% substrate Plantmax®; T6= vermiculite. The number of leaves, dry mass, leaf area index, culture growth rate, relative growth rate, net assimilation rate, specific foliar area, foliar area ratio and foliar weight ratio were evaluated. Higher growth of lettuce plants are produced by mixture of organic compound and substrate Plantmax®. The isolated use of vermiculite does not give good results for the growth of lettuce plants, but is an alternative for mixing with other substrates.