SPRING 1997
FINAL REPORT
PRESSURE BOMB
BY:
Mario Valenzuela-Vazquez
Artemio Escobedo-Mendoza
Jose Luis Almanza-Sandoval
Plant growth occurs when water balance within plants is favorable or in period of high plant water potential. Water potential acting directly or indirectly is a determinant of all plant functions, such as cell expansion, photosynthetic rate (stomatal conductance, dark and light reactions), respiration, biosynthesis, etc.
In an attempt to understand and measure the water function in plant tissues, several devices have been developed. The pressure bomb, also known as a plant water status console, is a useful instrument when doing research in plant water relationships. In addition, when data obtained with this device is properly correlated to soil water potential and potential evapotranspiration data, it is a useful tool for irrigation scheduling.
The pressure bomb determines the balance pressure of a cut plant's tissue. Such balance in pressure seems to be equivalent to the xylem pressure potential before the plant was cut. Other complementary issues of plant water status can be measured such as fuel turgor potential, symplastic water and bound water. There are several models of water status consoles, such as those constructed by Soilmoisture Equipment Corp. Some of these models are: Models 1000, 3000 and 3050.
PRESSURE BOMB MODEL 1000
PRESSURE BOMB MODEL 3000
PRESSURE BOMB MODEL 3005
Despite the different models, the basic structure is similar among all pressure bomb instruments. Their most important parts are: a stainless steel pressure vessel to hold the sample, a high pressure supply tank, a valve system and the chassis, and the red-out pressure test gauge.
Mario Valenzuela-Vazquez marioval@nmsu.edu
Artemio Escobedo-Mendoza aescobed@nmsu.edu
Jose Luis Almanza-Sandoval jalmanza@nmsu.edu
Asunción Ríos-Torres ariostor@nmsu.edu