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Pathogen infection drives patterns of nutrient resorption in citrus plants.

Cao J, Cheng C, Yang J, Wang Q - Sci Rep (2015)

Bottom Line: We investigated the effects of 'Ca.P resorption efficiency substantially decreased in infected C. reticulata plants relative to the healthy plants in summer, which may account for the marked decrease in the average fruit yield.However, for C. maxima plants, HLB had no significant effects on N:P ratio in live leaves and resorption efficiency as well as on fruit yield.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.

ABSTRACT
Nutrient resorption processes in the plants infected by pathogen remain poorly understood. Huanglongbing (HLB) is a destructive disease of citrus. HLB-pathogen 'Candidatus Liberibacter asiaticus' grows specifically in the phloem of hosts and may cause problems in the plant vascular system after infection. Therefore, it brings a great concern about the phloem nutrient transport and nutrient intra-cycling in HLB-affected plants. We investigated the effects of 'Ca. L. asiaticus' infection on nitrogen (N) and phosphorus (P) concentrations and resorption in different citrus species (i.e. Citrus reticulata, Citrus limon and Citrus maxima). HLB-pathogen infection had distinctive impacts on nutrient resorption in different species. P resorption efficiency substantially decreased in infected C. reticulata plants relative to the healthy plants in summer, which may account for the marked decrease in the average fruit yield. P resorption was more efficient in infected C. limon plants than in the healthy plants. However, for C. maxima plants, HLB had no significant effects on N:P ratio in live leaves and resorption efficiency as well as on fruit yield. Keeping efficient internal nutrient cycling can be a strategy of citrus species being tolerant to HLB.

No MeSH data available.


Related in: MedlinePlus

N:P ratios in live leaves of different citrus species.There were no significant differences in N:P ratio between sampling dates for all species, therefore the N:P ratios in June and October were compiled to calculate means ± Se (n = 10) for each species. * and ** above bars indicate significant differences at P < 0.05 and 0.01, respectively, derived from the results of paired t-tests.
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f4: N:P ratios in live leaves of different citrus species.There were no significant differences in N:P ratio between sampling dates for all species, therefore the N:P ratios in June and October were compiled to calculate means ± Se (n = 10) for each species. * and ** above bars indicate significant differences at P < 0.05 and 0.01, respectively, derived from the results of paired t-tests.

Mentions: Resorption efficiencies of N and P were significantly correlated with one another (r = 0.40, P = 0.027 for healthy plants and r = 0.83, P < 0.0001 for infected plants; Table 3); so were concentrations of N and P in senesced leaves (r = 0.75, P < 0.0001 for the healthy and r = 0.44, P = 0.015 for the infected). A significant correlation between N and P concentrations in live leaves was detected in infected plants (r = 0.66, P < 0.0001), but was not in healthy plants (r = −0.31, P = 0.091). There were opposing effects of ‘Ca. L. asiaticus’ infection on N:P ratios in live leaves, with a decrease in C. reticulata plants and an increase in C. limon plants (P = 0.03 and P = 0.01, respectively; Fig. 4). However, the effects ofthe infection on N:P ratios in senesced leaves were not significant (Table 2). The N:P ratio in live leaves was significantly correlated with P resorption efficiency (r = −0.36, P = 0.049 for healthy plants and r = −0.73, P < 0.0001 for infected plants). The correlation of N:P in senesced leaves and P resorption efficiency was significant only in healthy plants (Table 3).


Pathogen infection drives patterns of nutrient resorption in citrus plants.

Cao J, Cheng C, Yang J, Wang Q - Sci Rep (2015)

N:P ratios in live leaves of different citrus species.There were no significant differences in N:P ratio between sampling dates for all species, therefore the N:P ratios in June and October were compiled to calculate means ± Se (n = 10) for each species. * and ** above bars indicate significant differences at P < 0.05 and 0.01, respectively, derived from the results of paired t-tests.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4588592&req=5

f4: N:P ratios in live leaves of different citrus species.There were no significant differences in N:P ratio between sampling dates for all species, therefore the N:P ratios in June and October were compiled to calculate means ± Se (n = 10) for each species. * and ** above bars indicate significant differences at P < 0.05 and 0.01, respectively, derived from the results of paired t-tests.
Mentions: Resorption efficiencies of N and P were significantly correlated with one another (r = 0.40, P = 0.027 for healthy plants and r = 0.83, P < 0.0001 for infected plants; Table 3); so were concentrations of N and P in senesced leaves (r = 0.75, P < 0.0001 for the healthy and r = 0.44, P = 0.015 for the infected). A significant correlation between N and P concentrations in live leaves was detected in infected plants (r = 0.66, P < 0.0001), but was not in healthy plants (r = −0.31, P = 0.091). There were opposing effects of ‘Ca. L. asiaticus’ infection on N:P ratios in live leaves, with a decrease in C. reticulata plants and an increase in C. limon plants (P = 0.03 and P = 0.01, respectively; Fig. 4). However, the effects ofthe infection on N:P ratios in senesced leaves were not significant (Table 2). The N:P ratio in live leaves was significantly correlated with P resorption efficiency (r = −0.36, P = 0.049 for healthy plants and r = −0.73, P < 0.0001 for infected plants). The correlation of N:P in senesced leaves and P resorption efficiency was significant only in healthy plants (Table 3).

Bottom Line: We investigated the effects of 'Ca.P resorption efficiency substantially decreased in infected C. reticulata plants relative to the healthy plants in summer, which may account for the marked decrease in the average fruit yield.However, for C. maxima plants, HLB had no significant effects on N:P ratio in live leaves and resorption efficiency as well as on fruit yield.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.

ABSTRACT
Nutrient resorption processes in the plants infected by pathogen remain poorly understood. Huanglongbing (HLB) is a destructive disease of citrus. HLB-pathogen 'Candidatus Liberibacter asiaticus' grows specifically in the phloem of hosts and may cause problems in the plant vascular system after infection. Therefore, it brings a great concern about the phloem nutrient transport and nutrient intra-cycling in HLB-affected plants. We investigated the effects of 'Ca. L. asiaticus' infection on nitrogen (N) and phosphorus (P) concentrations and resorption in different citrus species (i.e. Citrus reticulata, Citrus limon and Citrus maxima). HLB-pathogen infection had distinctive impacts on nutrient resorption in different species. P resorption efficiency substantially decreased in infected C. reticulata plants relative to the healthy plants in summer, which may account for the marked decrease in the average fruit yield. P resorption was more efficient in infected C. limon plants than in the healthy plants. However, for C. maxima plants, HLB had no significant effects on N:P ratio in live leaves and resorption efficiency as well as on fruit yield. Keeping efficient internal nutrient cycling can be a strategy of citrus species being tolerant to HLB.

No MeSH data available.


Related in: MedlinePlus