Light Absorption and Carotenoid Synthesis of Pot Marigold (Calendula officinalis L.) in Response to Phosphorous and Potassium Varying Levels

Notulae Scientia Biologicae 01/2011;
Source: DOAJ


In order to provide additional information on the effects of elemental deficiency on factors that affect plant production in medicinal plants, a factorial field experiment as randomized complete block design was conducted on Calendula officinalis. Treatments were four phosphorus levels (P2O5) including 0, 40, 80 and 120 Kg ha-1 and four potassium levels (K2O) as 0, 50, 100 and 150 Kg ha-1. Results showed that applied treatments had significant effects on petal carotenoids and the highest amount of β - carotene obtained at 80 and 150 Kg ha-1 P2O5 and K2O, respectively. Effect of K2O on light interception and light use efficiency was significant and the highest radiation use efficiency achieved by applying 150 Kg ha-1 K2O. The highest yield of grain and dry flowers was recorded in the mixture of 80 and 150 Kg ha-1 P2O5 and K2O, respectively. In conclusion, using of K2O had greater effects on studied traits than P2O5.

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Available from: Alireza Pirzad
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    ABSTRACT: Aims This study aimed to determine the effect of arbuscular mycorrhizal (AM) fungi and phosphorus (P) supply levels on β-carotene concentrations in sweet potato (Ipomoea batatas L.) tubers. Methods Two commercial AM fungal isolates of Glomus intraradices (IFP Glintra) and Glomus mosseae (IFP Glm) which differ in their life cycles were used. Sweet potato plants were grown in a horizontal split-root system that consisted of two root compartments. A root-free fungal compartment that allowed the quantification of mycelial development was inserted into each root compartment. The two root compartments were inoculated either with the same or with different AM isolates, or remained free of mycorrhizal propagules. Each fungal treatment was carried out in two P supply levels. Results In the low P supply level, mycorrhizal colonization significantly increased β-carotene concentrations in sweet potato tubers compared with the non-mycorrhizal plants. Glomus intraradices appeared to be more efficient in increasing β-carotene concentrations than G. mosseae. Dual inoculation of the root system with the two mycorrhizal fungi did not result in a higher increase in tuber β-carotene concentrations than inoculation with the single isolates. Improved P nutrition led to higher plant tuber biomass but was not associated with increased β-carotene concentrations. Conclusions The results indicate a remarkable potential of mycorrhizal fungi to improve β-carotene concentrations in sweet potato tubers in low P fertilized soils. These results also suggest that β-carotene metabolism in sweet potato tubers might be specifically activated by root mycorrhizal colonization.
    No preview · Article · Nov 2013 · Plant and Soil