Spatial constraints also regulates final achene mass in the sunflower (Helianthus annuus L.) capitulum

In capitula of the cultivated sunflower (<em>Helianthus annuus</em> L.) achene size and mass commonly decrease from proximal to distal positions. Temporal limitation of resources of the distal achenes over the proximal ones has been the common explanation for this response. Nevertheless, because the capitulum architecture and expansion dynamics also interacts with achene growth and development, also space exert a coupled effect with resources on achene size along the inflorescence radius. In this work we removed young achenes from different capitulum positions [inner sector (IS) and outer sector (OS)] and applied an artificial restriction to the capitulum/achenes radial expansion. Removal of outer achenes significantly increased the final dry mass of the remnant ones between 17.1 to 27.6%. Removal of inner achenes also produced the same effect but in less magnitude, between 9.3 to 17.9% of the outer ones. The removal of outer achenes with the application of an artificial peripheral constraint did not significantly increase the dry mass of the remnant ones (2.7% of the inner and 7.1% of the control). Percentage of empty achenes significantly diminished in the middle sector (MS) in capitula with the outer achenes removed and in capitula with the outer achenes removed plus a peripheral constraint but in the range of 7.1% (MS achenes) and 2.7 % (IS achenes). Percentage of empty achenes of the MS did not change when the outer achenes were removed but was significantly lower when the OS was removed and the peripheral constraint was applied. This results suggest that a part of the reduced growth and development of IS and MS achenes is not only controlled by the competition for resources but also is restricted by space and pressure exerted by the neighboring ones.

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Effect of fertiliser type and mycorrhizal inoculation on growth and development of sunflower ( Helianthus annuus L.)

Rhizosphere ◽

10.1016/j.rhisph.2018.01.005 ◽

2018 ◽

Vol 6 ◽

pp. 11-19 ◽

Cited By ~ 1

Author(s):

A.M. Abobaker ◽

S.A. Bound ◽

N.D. Swarts ◽

K.M. Barry

Keyword(s):

Helianthus Annuus ◽

Growth And Development ◽

Helianthus Annuus L ◽

Mycorrhizal Inoculation

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Phytoremediation of Soil Contaminated With Heavy Metals Using the Sunflower (Helianthus Annuus L.)

Quality of Life (Banja Luka) - APEIRON ◽

10.7251/qol2103077t ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Merima Toromanović ◽

Vildana Jogić ◽

Jasmina Ibrahimpašić ◽

Aida Džaferović ◽

Samira Dedić ◽

...

Keyword(s):

Heavy Metals ◽

Experimental Study ◽

Helianthus Annuus ◽

Experimental Research ◽

Growth And Development ◽

Growing Season ◽

Helianthus Annuus L ◽

Low Concentrations ◽

Dangerous Substances ◽

Stems And Leaves

Phytoremediation has proven to be a suitable method for removing heavy metals from the soil with the help of plants. To examine the phytoremediation potential, the experimental study monitored the influence of high and low concentrations of heavy metals (Pb, Cd, and Zn) on Helianthus annuus L., as well as their accumulation in seeds, roots, stems and leaves. The experiment was carried out during one growing season in outdoor conditions, in pots with a volume of 5L in which Helianthus annuus L. was planted, and the soil was contaminated with these heavy metals in concentrations below and above the maximum allowable concentration prescribed by the Rulebook on Determining Permissible Quantities of Harmful and Dangerous Substances in Soil and Methods of Their Testing. After growth and development of the plant, the experimental research examined the accumulation potential of the plant, the growth of the plant itself and its ability to survive depending on different concentrations of heavy metals. By processing the obtained results, statistically significant differences of heavy metals were determined in individual parts of the plants, depending on the applied concentration. The highest concentration of Zn was recorded in the leaves of the plant in the amount of 18.21 mg/kg, and the lowest concentration in the stem, 3.92 mg/kg. The measured values of heavy metals Cd and Pb differ from the above because the lowest concentrations of these heavy metals were recorded in the seed, and were 12.02 mg/kg for Pb and 9.20 mg/kg for Cd, which is a statistically significantly lower determined value relative to other parts of the plant.

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