Soil Volume: The Effect of Pot Size on Roots and Canopy Growth Performance of Cactus Pear

Sawsan Hassan, G. Liguori, Giuseppe Sortino, Mounir Louhaichi, Paolo Inglese. (30/3/2017). Soil Volume: The Effect of Pot Size on Roots and Canopy Growth Performance of Cactus Pear. Coquimbo, Chile.

Abstract

The influence of soil volume on roots and canopy growth performance of cactus pear (Opuntia ficus-indica) was studied at Palermo University. In November 2014, 1 year old Opuntia ficus-indica cladodes were planted in five different size of pots 49, 33, 18.5, 9 and 6 L. Three replicates (plants) per pot size were dug out at 6 and 12 months. The resulting experimental design was a randomized complete block design with three replications (each replication was one plant in one pot size). Roots were washed and roots length was manually measured. Roots fresh and dry weigh was obtained. Cladode surface area, cladode thickness, number of new cladodes, cladode fresh and dry mass were measured and recorded for each plant. Results indicate a significant effect of pot sizes (P<0.01) on root length, root fresh weight, and dry weight in both studied intervals. Roots of cuttings planted in pot sizes 49 and 33 L exhibited significantly the highest values of length, fresh and dry weight. Increasing the pot size enhanced the thickness, fresh and dry weight of the cladodes (P<0.01) in both interval but not the surface area. Mother cladode dry weight was affected by the smallest pot size (P<0.01). In the first interval, number of the new cladodes for both first and second generation was not affected by the pot size. On the contrary, in the second interval, pot size exhibited significant effect on new cladode production and pot sizes 49 and 33 L recorded the highest (P<0.05) number of new cladodes. In both intervals no second generation new cladodes were observed in 9 and 6 L pot sizes. In both intervals, the root dry weight was strongly correlated to the root length and fresh weight (r =0.89 to 0.99, P < 0.01), total cladodes fresh and dry weight (r =0.64 to 0.95, P < 0.01) and to mother cladode fresh weight (r =0.71 to 0.95, P < 0.01). These results suggest that the limitation of soil availability resulted in root and canopy growth limitation.