Articles
Evaluation of two mutant citrus rootstocks under boron toxicity conditions
Article number
1448_19
Pages
163 – 170
Language
English
Abstract
Boron (B) toxicity is a common limiting factor in both arid and semi-arid regions, such as the Mediterranean Basin.
Citrus trees are sensitive to B-toxicity, which generates a negative impact in citrus orchards.
In this work, two new mutant rootstocks tolerant to salinity (MM4A and MM4B), derived from Citrus macrophylla (MA), were assessed in terms of their behaviour to B-toxicity, along with C. macrophylla as a control, a common commercial citrus rootstock in the Mediterranean Basin.
Three irrigation treatments were established in this experiment: 1) a modified Hoagland solution (HG); 2) HG with 1 mM H3BO3; 3) HG with 2.5 mM H3BO3. Plants were irrigated three times per week, for 6 weeks, under growth chamber conditions.
At the end of the experiment, several growth and physiological parameters were measured for each rootstock.
When growth parameters were analysed, it was observed that in MA and MM4B, treatments with H3BO3 decreased the productivity and the relative plant growth (RPG), but no significant differences were observed in MM4A. Treatment 3 resulted in a lower increase in the number of leaves in MA and MM4B, at the end of the experiment, nevertheless, significant differences were not observed in MM4A. Treatments 2 and 3 caused an increase in the number of damaged leaves across all genotypes, almost 100% leaves were damaged in treatment 3 in all three genotypes.
Dry weight in shoots and roots decreased in MA and MM4B with the B increase, however, no significant differences were observed in MM4A. Chlorophyll concentration was not affected by the treatments in MA and MM4A, observing a chlorophyll level reduction in MM4B in treatments 2 and 3. The photosynthesis rate and stomatal conductance parameters decreased with B treatments in MA and MM4B, and with the treatment 3 in MM4A. The assessment of mutants MM4A and MM4B behaviour showed that the mutant MM4A was more tolerant to B-toxicity conditions than MA and its mutant MM4B.
Citrus trees are sensitive to B-toxicity, which generates a negative impact in citrus orchards.
In this work, two new mutant rootstocks tolerant to salinity (MM4A and MM4B), derived from Citrus macrophylla (MA), were assessed in terms of their behaviour to B-toxicity, along with C. macrophylla as a control, a common commercial citrus rootstock in the Mediterranean Basin.
Three irrigation treatments were established in this experiment: 1) a modified Hoagland solution (HG); 2) HG with 1 mM H3BO3; 3) HG with 2.5 mM H3BO3. Plants were irrigated three times per week, for 6 weeks, under growth chamber conditions.
At the end of the experiment, several growth and physiological parameters were measured for each rootstock.
When growth parameters were analysed, it was observed that in MA and MM4B, treatments with H3BO3 decreased the productivity and the relative plant growth (RPG), but no significant differences were observed in MM4A. Treatment 3 resulted in a lower increase in the number of leaves in MA and MM4B, at the end of the experiment, nevertheless, significant differences were not observed in MM4A. Treatments 2 and 3 caused an increase in the number of damaged leaves across all genotypes, almost 100% leaves were damaged in treatment 3 in all three genotypes.
Dry weight in shoots and roots decreased in MA and MM4B with the B increase, however, no significant differences were observed in MM4A. Chlorophyll concentration was not affected by the treatments in MA and MM4A, observing a chlorophyll level reduction in MM4B in treatments 2 and 3. The photosynthesis rate and stomatal conductance parameters decreased with B treatments in MA and MM4B, and with the treatment 3 in MM4A. The assessment of mutants MM4A and MM4B behaviour showed that the mutant MM4A was more tolerant to B-toxicity conditions than MA and its mutant MM4B.
Publication
Authors
C.M. Rodríguez, Y. Jiménez, A. Frías, O. Pérez-Tornero
Keywords
breeding, Citrus macrophylla, desalinated water, H3BO3, mutagenesis, salinity
Groups involved
Online Articles (103)