The Comparison on Growth of Neck Orange (Citrus reticulate Blanco) Grafted on Five Citrus sp. Rootstock

Abstract

The present study was about the comparison on growth of Neck orange (Citrus reticulata Blanco) on five Citrus sp. rootstocks containing with Native pomelo (C. grandis (L.), Thongde pomelo (C. maxima (Burm.f.), Citron (C. medica), Kaffer lime (C. hystrix), and Bitter orange (C. × aurantium). To evaluate the suitable rootstock for Neck orange production, five-year-old Neck oranges were grafted with five different Citrus sp. rootstocks in a cleft method. It was performed by cleft grafting with branches that were 5 years old. The sample plants were planted in 17-inch polybags for 7 months at the Fruit Department of Plant Science, Faculty of Agriculture, Rajamangala University of Technology Srivijaya, Nakhon Si Thammarat Campus. A completely randomized design (CRD) with five replications and four trees per representative was used for the experiment. The result showed that rootstock of Bitter orange generated the highest average plant height, 40.31 cm, with a significant difference, followed by Kaffer lime, Native pomelo, Thongde pomelo, and Citron, at 38.44, 38.32, 37.15, and 21.68 cm, respectively. In the case of scions’ height, the rootstock of Bitter orange gave the highest of average height of scions (23.30 cm), followed by Kaffer lime, Native pomelo, Thongde pomelo, and Citron, at 21.75, 21.74, 15.67, and 11.30 cm, respectively. In addition, after 7 months of cleft grafting, the highest number of branches per tree of Neck orange was found on the orange tree from a rootstock of Bitter orange. It was 4.47, and the next highest numbers were 4.45, 4.40, 2.64, and 2.42 branch/tree for Kaffer lime, native pomelo, Thongde pomelo, and Citron. Therefore, Bitter orange is a superior rootstock choice than Citrus sp.