Abstract:
Plant growth is seriously affected by abiotic stresses such as drought, salinity, heavy metals or temperature extremes. Salinity is one of the most important limiting factors for agricultural crop production and sustainability particularly for oil-seed crops all around the world. The adverse effect of salt appears on whole plant level at almost all growth stages such as germination, seedling, vegetative and reproductive growth. Phytohormones play a crucial role by regulating plant responses to salinity stress that ultimately lead to plant adaptation to harsh environment. The present study aimed at determining the effect of exogenous application of abscisic acid and indole acetic acid on root and shoot growth of Helianthus annuus L. under NaCl salt stress. A pot experiment was conducted in a complete randomized design with four factors and five treatments each with three replicates i.e. 0mM(T0), 50mM(T1), 100mM(T2), 150mM(T3), 200mM(T4). The pots were arranged in four blocks, one block consisting of five different levels of sodium chloride, the other two containing salt along with a combination of indole acetic acid (15µM) and abscisic acid (15µM) separately. The forth block containing sodium chloride combined with indole acetic acid and abscisic acid. Results of this study indicated that high salinities caused decline in all morpho-anatomical attributes measured. Higher levels of salinity caused a reduction in plant height, root and shoot length, leaf area and fresh weight. Anatomical changes were also noticed in terms of epidermis cell area, thick sclerenchyma, increased metaxylem vessel area and cortical area and thick endodermis. It was concluded that high salinity caused ionic imbalance and inhibit water uptake which results in osmotic and ionic stress leading to smaller cell size and cell injury. Exogenous application of indole acetic acid had appeared to ameliorate the inhibitory effect of salt on root and shoot in terms of better growth. In addition ABA also played the role in salt tolerance either by decreasing or maintaining the growth close to those of control plants. However, the combination of IAA and ABA had a slight but non-significant promontory effect on growth of the plant
Page(s):
125-125
DOI:
DOI not available
Published:
Journal: Abstract Book on Global Science Technology and Management Conference, Volume: 0, Issue: 0, Year: 2023
Keywords:
Salt stress
,
Sunflower
,
abscisic acid
,
indole acetic acid
,
Helianthus annuus