Eastern Morocco Argania spinosa propagation and growth: A follow-up study

Abstract

The Argan tree (Argania spinosa L) is an endemic species, located mainly in the southwest of Morocco, but also exists as a relic in the northeast of the country. It is a species of great biological, ecological and socio-economical importance. As part of the domestication of the Argan tree at the national and regional scale, a study was carried out which aims to optimize the mode of sexual multiplication of eastern Morocco Argan tree, by studying the effect of the nuts weight on the rate of imbibition, the rate of germination, the number of seedlings resulting from each nuts classes of weight, and the growth of the seedlings. The experimental treatment is mainly formed by three classes of nuts weight. The first class named W-1 is formed by nuts with a weight less than 2g. The second-class W-2 is characterized by nuts of a weight ranging from 2 to 3.5g. The last class is W3 and has a weight of over than 3.5g. The germination was conducted in a phytotronic room at a controlled temperature (26  2°C). While, the follow-up of the seedlings’ growth was carried out in a glass greenhouse, and the rate and kinetics of imbibition were performed in a separate experiment. The results indicated that the nuts were water permeable and the rate of imbibition was found to be proportionally related to weight and varies between 18.18 % W1 and 32.21% W3 after 48 hours. On the other hand, for the germination rate, the nuts of class W1 showed the highest germination rate (84.4%) followed by those of class W2 (72%) and finally class W3 (68.8%). However, Argan nuts could contain more than one kernel and produce more than one seedling per nut and this allowed to have a high number of produced plants and increased the germination rate in particular for the classes W2 and W3, (99.2% and 97.2%). The results also showed that the growth and the development of seedlings were proportionally related to the weight of the kernels.