Effect of Substrate on the Growth of Grewia coriacea (Malvaceae) Seedlings

Domestication of Grewia coriacea Mast. (Malvaceae) threatened to disappear in Lefini Basin requires looking for vegetable growth conditions of their seeds. The study is initiated to evaluate the effect of the substrate on vegetative growth of the seedlings from germination of the pretreated stones. Whole fruits harvested on 5 trees choosed in natural forest and entire stones resulting from decortication are material used for germination tests. Obtained stones were immersed in boiling water and nitric acid at 65% as well as scarification of their teguments made by using an abrasive paper. The stones grew in pots containing sand and mould. The following parameters are evaluated for the resulting seedlings: stems height, collet diameters, plastochrone, number of leaves, internodes, ramifications and roots length. Height of seedling growing on the mould is higher than that of those developing on the sand whatever the treatments. Height of stems resulting from the whole fruits is inferior to 6.3 cm compared to untreated stones, stones immersed in nitric acid at 65% during 15 min and that the scarified stones on mould and sand. Collet of seedlings developing on sand has a diameter of 0.47 cm compared to that of the seedlings developing in the mould which is 0.43 cm. On the two substrates, seedlings resulting from scarified stones, entire stones and those resulting from stones treated in the nitric acid and developing on sand and mould which have the most leaves, internodes, ramification and roots length compared with that recorded on entire fruits. Stones immersed in 65% nitric acid during 15 min and from the scarified stones present better height of the stems, a more significant collet diameter, a high leaves number, internodes and the stems ramification. On mould, the seedlings resulting from stones treated present a better vegetative growth compared to those of the sand.