Evaluation of the resistance of few citrus rootstocks to alkalinity by applying a faste test of secreening

摘要

Alkalinity of Moroccan soils is the major abiotic constraint on citrus production area. The best choice of citrus rootstocks adequate and resistant is a better solution to avoid this problem. The aim of this study is to develop a fast test of citrus rootstocks screening towards alkalinity. The alkaline stress was applied on ten citrus rootstocks two month old, using irrigation with a Hoagland and Arnon solution added with 1 g CaCO3/L and adjusted at various pH levels 6, 7 and 9. Observations concerned symptoms incidence and severity of iron chlorosis after two months of rearing. Results permitted to classify?Poncirus?trifoliata?and Flying dragon as the most sensitive to alkalinity stresses, whereas,?Citrus?volkameriana?and?Citrus?macrophyllawere resistant. These conclusions are equivalent with those obtained with old citrus rootstocks in field trials.?Keys words:?Citrus, rootstocks, alkalinity, screening.