Hernández LF^1,2, PM Bellés³, MA Bidegain^4,5, PD Postemsky⁴

Phyton-International Journal of Experimental Botany, Vol.87, pp. 198-208, 2018, DOI:10.32604/phyton.2018.87.198

Abstract Absence or underdevelopment of sunflower fruits come usually from failure in fertilization, stresses as well as physiological and morphological defects in the ovary. Thigmomorphogenesis has never been included as a possible cause. We have previously shown that a 2-3 day fertilization shift can occur between neighboring florets in the sunflower capitulum. It is proposed here that those ovaries with advanced fertilization can generate a significant radial and axial compressive stress on ovaries with delayed fertilization. This mechanical stimulus could be strong enough to trigger a thigmo response that affects further ovary development. In vivo tests were performed, isolating ovaries by… More >

Díaz-López E¹, A Morales-Ruíz¹, A Olivar-Hernández¹, HR Bravo-Delgado², JM Loeza-Corte³

Phyton-International Journal of Experimental Botany, Vol.87, pp. 18-24, 2018, DOI:10.32604/phyton.2018.87.018

Abstract Sunflower is a crop that is used as ornamental, oleaginous, forage, and currently as a bioremediation plant, of hard water affected soils. For this reason, the main objective of this investigation was to study the effect of potassium fertilization on yield under field conditions, and the effect of gibberellic acid (GA₃), at postharvest of inflorescences. Two experiments were established, under field and laboratory conditions. In the field experiment, four levels of potassium, 0, 50, 100 and 150 kg/ha were evaluated, under a randomized complete block design and four replicates (4×4) = 16 experimental units. The variables evaluated were agronomic and… More >

Maryam Monazzah¹, Sattar Tahmasebi Enferadi^1,*, Zohre Rabiei¹ and Alessandro Mattiello²

Phyton-International Journal of Experimental Botany, Vol.88, No.2, pp. 149-159, 2019, DOI:10.32604/phyton.2019.05053

Abstract Helianthus annuus L. as an oil seed crop is widely grown throughout the world. One of the most destructive diseases of sunflower is stem rot caused by Sclerotinia sclerotiorum. Oxalic acid is the major virulence factor of this necrotrophic pathogen. It is important to further investigate plant responses to this non-specific toxin. Therefore, in the present study, we compared the patterns of total soluble proteins and xylem morphology of partially resistant and susceptible sunflower lines after treatment with Sclerotinia culture filtrate. The basal stems of both lines were treated with 40 mM oxalic acid (pH 3.7) of fungus culture filtrate… More >