Effect of watering regime on inoculum density of Phytophthora spp. in the rhizosphere of young plantations of the sidi aissa clementine variety grafted onto different rootstocks in the Gharb region (Sidi Allal Tazi) of Morocco
Year: 2022
Type: article
Abstract: We examined the combined influence of irrigation regime and rootstock on Phytophthora spp. population density in citrus rhizosphere under field conditions. We carried out the study in a young orchard of Clementine, variety Sidi Aissa, grafted onto five rootstocks:, i.e. carrizo citrange, citrange C35, Citrus macrophylla, sour orange and the hybrid Cleopatra mandarin x citrange Carrizo 30577. Three water regimes were applied: Control (T0) irrigated at 100% of ETc, and deficit irrigation (T1) and (T2) at 75% and 50% of ETc, respectively. Results show that Phytophthora spp. Inoculum density varied significantly between the different irrigation regimes and rootstock genotypes. Phytophthora spp. density was significantly lower under the more severe deficit irrigation T2 than under T0 or T1. Also, a significant and positive correlation was found between soil moisture and inoculum density of Phytophthora spp. in the rhizosphere of C. macrophylla and Carrizo citrange rootstocks. Among rootstocks, the highest population densities of Phytophthora spp. were demonstrated for C. macrophylla and sour orange rhizosphere under 100% ETc regime, while no inoculum was evidenced from the root zone of C. macrophylla under 50% ETc. Results showed that Carrizo citrange and C. macrophylla were more sensitive to soil moisture indicating that watering regime is a key factor to minimize Phytophthora spp. density in the rhizosphere of these rootstocks. Results also revealed that Carrizo citrange and C. macrophylla rootstocks can be recommended under deficit irrigation in order to reduce Phytophthora spp. infection in citrus orchards.
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W3136480802