Effect of growing media, irrigation rates and grafting on growth and flowering of hibiscus spp. plants

Two separate filed experiments were conducted at the nursery of Horticulture Research ýInstitute, Giza throughout two successive seasons (2007/2008 and 2008/2009) with the ýaim of investigating the possibility of using grafting for the propagation of Hibiscus rosa-ýsinensis L. and Hibiscus syriacus plants as well as determining the most suitable ýirrigation level and growing media for producing plants of a high quality of Hibiscus ýrosa-sinensis L. The results emphasized that cleft grafting was the best in most cases for ýimproving most plant traits. Fire Truck stock proved its mastery in improving most of ýplant traits in both seasons. ýþ þCooperi Albaþ þý and Fire Truck scion were the best in most ýcases for improving most of plant morphological traits. Similarly, improvements in ýchemical constituents of the plant were also observed due to using ýþ þFire Truck'scion ýfollowed by that of either Charles Septemberþ þý or Cooperi Alba scions. The interactions ýrevealed the superiority of the combined effect between Fire Truckþ þas a rootstock and ýeither Cooperi Alba or Fire Truck' scions for improving most plant traits studied. ýLikewise, the results of bud grafting method behaved about the same direction for its ýeffects on plant morphological traits and chemical constituents with the superiority of ýcleft grafting in this concern. The results cleared that applying the moderate irrigation ýlevel (0.75 L/pot) was the best for improving plant morphological traits and inducing the ýearliest flowering, but with the exception of using the highest level (I L/pot) which gave ýhighest number of branches and leaves/plant. Meanwhile, the lowest irrigation level (0.50 ýL/pot) or the moderate one (0.75 L/pot) were the best for raising the accumulation rate of ýplant chemical constituents. Using the mixture of peatmoss + perlite + 10% compost ýproved its mastery in improving plant morphological traits with producing early ýflowering. The interactions, proved that growing plants in the mixture of peatmoss + ýperlite + 10% compost with applying either the moderate irrigation level (0.75 L/pot) or ýthe highest one (IL/pot) gave the utmost high values of plant morphological traits. ýLikewise, growing plants in the mixture of peatmoss + 10% compost and supplied with ýthe moderate irrigation level(0.75 L/pot) proved their prevalence in raising some ýchemical constituents of the plants in the two seasons. From the aforementioned results, it ýcould be recommend to use grafting in propagation with using Fire Truck as a rootstock ýand the same cv. or Cooperi Alba as scions for cleft grafting. In addition, using the ýmixture of peatmoss + perlite + 10% compost for growing plants with supplying them the ýmoderate (0.75 L/pot) irrigation level (0.75 L/pot) for producing plants of good quality of ýsuperior morphological traits and chemical constituents.ý