Relationships between stomatal behaviour, spectral traits and water use and productivity of green peas (Pisum sativum L.) in dry seasons

Physiological Responses of Selected Vegetable Crop Species to Water Stress

“…A significant difference can be demonstrated in stomatal density of leaves between snap beans, green peas and sweet corn grown under non-irrigated and deficit irrigated (50% water deficiency) conditions ( Table 2). On the basis of 3 year experiments, on the lower epidermis of leaves the stomata density was significantly higher for snap beans under moderate and severe water stress and it was similarly high for sweet corn only in severe water deficiency, but no difference could be shown for green peas in comparison with the optimal water supplied plants [14,15,88]. On the upper epidermis of leaves more and larger sized stomata can be found for snap beans exposed to drought while there were fewer similar sized stomata for the green peas compared to the irrigated plants (Table 2).…”

“…Sensitivity of plants to water stress such as snap beans and green peas differs with the stages of development. During the early stages of vegetative growth most crops are less sensitive to water scarcity [2,3,12,13], but during the generative stage the water deficiency results in changes of many physiological traits [2,[14][15][16], causing the disturbance of fertility and reduction of yield. During flowering of legume plants water stress increases the ratio of flower drop [17], decreases the pod numbers and seed abortion in the pods [18,19] and increases the ratio of curved pods [20].…”

“…The physiological characteristics that have an important role in the defence against drought can be measured by remote sensing techniques using non-destructive methods in open field conditions. The leaf photosynthetic activity of plants can be monitored with measurement of chlorophyll content using a portable chlorophyll meter and chlorophyll fluorescence while the measurement of stomatal conductance indicates the severity of water stress [2,3,14]. Spectral vegetation indices such as the green normalized vegetation index (GNDVI) and the normalized differential vegetation index (NDVI) were used for monitoring the growth of the plant to detect the water stress and for yield prediction [36][37][38][39].…”

“…Nevertheless, yellow-podded snap bean varieties had 13-18% larger sized stomata on the adaxial surface of leaves of plants exposed to water deficiency in comparison with the irrigated plants [15]. A larger stomatal density was observed for late ripening green pea varieties [14] and late ripening sweet corn hybrids under water scarcity [88] than for the short duration ones. Nevertheless, the distribution and size of stomata can be different on both areas and surfaces of the same leaf.…”

“…Others [89] found that the relationship between stomatal density and WUE was positive and the size of stomata correlated negatively with the WUE for grass peas. [14,15,88], µ = micron, I0 = non-irrigation, DI = deficit irrigation, WI = optimal water supply.…”