R.B. Hamdan1*, I. Akel1, A. El-Khatib1, I. Ismail2 and H. Hassan1
(1) General Commission for Agricultural Scientific Research, Latakia Research Center, Syria; (2) Department of Plant Protection, Faculty of Agricultural Engineering, Latakia University, Syria.
*Email address of the corresponding author: [email protected]
This study was conducted to identify tolerant rootstocks to infection with Citrus tristeza virus (CTV, genus Closterovirus, family Closteroviridae). The work was carried out in two phases during the period 2017-2021, the first phase at the Ciano Research Station affiliated with the Latakia Research Center, in which four genotypes were cultivated: sour orange, Cleopatra mandarin, Carrizo citrange, and Citromilo 1452, to obtain uniform seedlings of the same age and grown under the same conditions. The second phase was conducted at the Agricultural Research Center in Lattakia, in which the seedlings were inoculated with a local CTV isolate after placing them under insect-proof netting to prevent insect entry and exit. The seedlings were monitored periodically to record symptoms appearance caused by CTV infection on each rootstock. The proline content in seedlings infected with CTV was compared to healthy seedlings. Results obtained showed that the CTV symptoms first appeared on sour orange with higher severity compared to Carrizo citrange. Infection with CTV caused decrease in the growth of sour orang and Cleopatra seedlings, while the hybrids of Poncirus trifoliata were not affected. Proline content in the leaves of the rootstocks infected with CTV increased compared to their respective healthy control, with a significant difference observed in Citromilo 1452. These results suggest that trifoliate orange hybrids are promising genotypes to be used as rootstock to tolerate citrus infection with CTV.
CTV, rootstocks, citrus, proline
https://doi.org/10.22268/AJPP-001508