Response of hibiscus sp. plants to different types of cleft grafting

This investigation was performed at the nursery of Horticulture Research Institute, Giza throughout two successive seasons (2007/2008 and 2008/2009) with the aim of investigating the possibility of using grafting for the propagation of Hibiscus rosa-sinensis L. and Hibiscus syriacus L. plants of good quality. Different types of cleft grafting were carried out by using different scion of Hibiscus rosa-sinensis cultivars Fire Truck, Charles September, Miss Kitty, Cane Fire, Cooperi, and two scions for Hibiscus syriacus 'Alba and Blue' for grafting two Hibiscus rootstock cultivars Fire Truck and Apple Blossom in both seasons. The results emphasized that `Fire Truck' stock was the best in improving most of plant traits in both seasons, when compared with those obtained from the other stocks used `Apple Blossom'. It increased survival percentage, the length/scion, number of main branches/scion, stem diameter and fresh weight of newly established plants, besides the improvement of some chemical constituents of the plant, as it increased total chlorophylls and carbohydrates content in the leaves, in addition to decreasing leaf phenol content. Scion cultivars also differed in their effects on the above mentioned traits. 'Cooperi' and `Fire Truck' scions were the best in most cases for improving most plant traits as they increased survival percentage, the length/scion stem diameter and fresh weight of newly established plants. Meanwhile, the number of main branches/plant increased as a result of using 'Cooperi' scion in grafting whereas a decrement on the registered values was detected in most cases due to using `Miss Kitty' scion. Similarly, an improvement on chemical constituents of the plant was also observed due to using Fire Truck` scion followed by that of either `Charles September' or 'Cooperi' scion as they increased leaf total chlorophylls and total carbohydrates contents, besides their decrement effect on phenols content in leaves. In contrast, undesirable effects were observed in most cases on chemical constituents of the plant due to using `Miss Kitty' scion in grafting. The interactions revealed the superiority of the combined effect between `Fire Truck' as a rootstock and either 'Cooperi' or `Fire Truck' scions in improving most plant traits studied. Also, using Fire Truck cv. as a rootstock with using the same cv. as a scion or `Charles September' scion had a marked effect in elevating the total chlorophyll and total carbohydrate contents in leaves. From the aforementioned results, it could be recommended to use `Fire Truck' as a rootstock with using the same cultivar or 'Cooperi' as a scion.