Cladode biomass composition of selected clones from an Opuntia spp. Collection

Species of the genus Opuntia are an important fodder resource, notably in lands facing global warming and desertification due to their intrinsic drought resistance. In order to evaluate the best selection for this purpose, the cladode biomass of 16 clones of Opuntia ficus-indica, O. rastrera and O. dillenii was analysed for chemical composition. Young cladodes were harvested at the end of the growth in the last decade of August. Three clones showed cladode fresh weight over 600 g: 'Castelsardo', 'Sanguigna San Cono', and 'Alghero'. The lowest cladode fresh weights were observed for the selection of O. dillenii with 75.8 g and the clone 'Gialla lungomare CT' with 157.4 g. Dry matter content over 10% was observed in cladodes from three clones of O. ficus-indica ('Gialla lungomare', 'Gialla' and 'Laconi') and from the clone of O. dillenii. The remaining clones evidenced cladode dry matter content between 6.1 and 9.5%. Ash content of the dry tissue was 26.6% for 'Villagrande' clone and 24.6% for 'Gialla'. All the other clones ranged between 22.5 and 17.2% of ash content on a dry weight basis. The highest nitrogen content was in cladodes of O. dillenii with the value of 0.89% of the dry matter and in the 'Villagrande' clone with 0.86%, while the lowest record of 0.31% was found for the clone 'Castelsardo'. The neutral detergent fibre (NDF) was 20.1% of the dry matter for 'Gialla lungomare CT' clone, and 7.7% for 'Castelsardo'. The acid detergent fibre (ADF) varied from 17.9% for 'Gialla' to 12.6% for 'Castelsardo'. Acid detergent lignin (ADL) ranged between 2.24% of 'Bianca di Bronte' and 0.50% of 'Rossa Piazza Armerina'. The value of the young cladodes as fodder was confirmed and the possibility to select clones with higher nutritional performance clearly demonstrated.