(N/A) Plant hormones,also known as phytohormones,are chemical substances produced naturally in plants that regulate growth,development,and physiological responses. Their general effects include:
$1$. Growth Promotion: Auxins,gibberellins,and cytokinins promote cell division,cell elongation,and tissue differentiation.
$2$. Growth Inhibition: Abscisic acid $(ABA)$ acts as a growth inhibitor,promoting dormancy in seeds and buds,and inducing stomatal closure during water stress.
$3$. Developmental Regulation: Hormones control processes like flowering,fruit ripening (e.g.,ethylene),and senescence (aging).
$4$. Stress Response: They help plants adapt to environmental stresses such as drought,salinity,and temperature fluctuations.