HORTICULTURE

Detailed explanation-1: -Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata. Light is the main trigger for the opening or closing. Each guard cell has a relatively thick cuticle on the pore-side and a thin one opposite it.

Detailed explanation-2: -A pair of guard cells surrounds each stoma, and these cells control the opening and closing of the stomatal pore between them. Guard cells regulate this opening and closing in response to a wide variety of environmental signals, such as day/night rhythms, CO2 availability, and temperature.

Detailed explanation-3: -Two guard cells surround each stomatal pore, and changes in turgor pressure of the guard cells regulate the size of the pore aperture. An increase in guard cell turgor results in stomatal opening, whereas a reduction in turgor leads to stomatal closure (Willmer and Fricker 1996).

Detailed explanation-4: -Stomata are pores (holes) in the epidermis of plants. Guard cells are the pairs of cells, shaped a bit like parentheses or two sides of a donut, that flank the stoma. The guard cells regulate when the stoma is open or closed, which in turn regulates gas exchange with the environment and the rate of transpiration.

Detailed explanation-5: -Guard cells optimise leaf gas exchange in response to changing environmental conditions and their turgor is controlled by alterations in atmospheric CO2 concentration, light intensity, humidity and the drought hormone abscisic acid.