Articles
EVALUATION OF SOME CLONAL QUINCE ROOTSTOCKS IN CALCAREOUS SOIL
An initial evaluation in hydroponic culture compared the following clonal quince rootstocks, all selected by the "Dipartimento Coltivazione e Difesa delle Specie Legnose – Sezione Coltivazioni Arboree" In Pisa: Ct.S. "402", "404", "407", "408", "409" and Ct.S. "207", "209", "211" and "212". This phase was conducted in the spring-summer period, adding 0, 10, 20 and 30% concentrations of calcium carbonate to the nutrient solutions.
Subsequently, the clones which had shown the more favourable responses in the stress phase, Ct.S. "211" and "212", were compared with two well-known selections, "MA" and "BA29" in a calcareous soil.
The trees were placed in containers, in a non calcareous soil, medium-texture base soil mixed with calcium carbonate to obtain mean active lime concentration of 0%, 2.3%, 4.0% and 10.5%.
During the two-year trial, chemical analyses were performed to determine the total lime, active lime, iron content end the pH of the soil; moreover the iron, carotenoid and chlorophyll content of the leaves.
Morphophysiological observations were also made, concerning vegetative growth and any symptoms of chlorosis in the leaves.
The results show different levels of resistance to calcareous soils among the various clones.
Ct.S. "211" and "212" were less sensitive to the presence of lime than the other clones, behaving similarly to "MA" and showing a greater resistance than "BA29".