Response of Yellow Quality Protein Maize Inbred Lines to Drought stress at Seedling Stage

Abstract

This study seeks to evaluate the response of 17 yellow Quality Protein Maize (QPM) inbred line seedlings to drought stress (DS), using different morphophysiological traits (plant height (PH), chlorophyll content (CC), stem diameter (SD), proline content (Pro), photochemical efficiency of photosystem II (PS II), canopy temperature (CT) and substomatal carbon dioxide concentration (Ci). The experiment was laid out in a randomized complete block design (RCBD) and replicated three times in a growth chamber. The seedlings were exposed to DS treatment by growing them at 20% field capacity. The control/well-watered (WW) treatments were kept at 80% field capacity throughout the experiment. Highly significant differences (p < 0.001) were observed for PH, SD, and Pro across environments. On the other hand, significant differences (p < 0.05) were observed for CC and PS II, while DS had no significant effects on Ci and CT. Proline content increased under DS compared to WW conditions. Inbred lines L34, L7, L5, L2, L16, and L6 had approximately equal or more Pro than the drought tolerant check (ZM1523). As such, these lines were regarded as drought tolerant. Taking all measured parameters into consideration, L7 performed notably better than the other inbred lines under DS.

Maize Open-Pollinated Populations Physiological Improvement: Validating Tools for Drought Response Participatory Selection

“…Contrary to what was reported by Chiuta and Mutengwa [76] in maize, no significant variation of Chla or b content was observed under water-deficit conditions. However, a significant decrease in the Chla/Chlb ratio was observed in both populations and a significant increase in carotenoids content in 'Fandango'.…”

“…Growth is the trait in plants that is most sensitive to water deficit, with decreases in growth preceding decreases in photosynthesis [74]. Indeed, in our field study, and in agreement with previous results in maize populations [75][76][77] plant stem height (PH) was already affected by water deprivation in all the four populations at a moderate water deficit (20% SWC), while for the majority of the populations, leaf gas exchange parameters of the stress exposed plants were similar to that of the non-stressed plants until 87% of the soil moisture was depleted (13% SWC). A reduction on shoot length (SL) when water deficit was still moderate (25-15% SWC) was also observed for maize seedlings grown under the growth chamber conditions experiment agreeing with previous results from Reference [67].…”

“…In our study, and at moderate stress (17% SWC) 'Caniceira' already showed a significantly smaller PI ABS score from 'Bilhó' or 'Fandango'. This may anticipate marked differences concerning plant vitality, PSII function and susceptibility to photoinhibition as already proposed in maize by Chiuta and Mutengwa [76].…”

Effect of Water Supply on Spectral Traits and Their Relationship with the Productivity of Sweet Corns

“…It has been reported that the spectral reflectance on the leaf was higher for maize [25], snap beans [24], and green peas [16] under drought stress than under optimal water supply conditions. Others [35] recorded lower chlorophyll content (SPAD unit) for most inbred maize lines under drought stress condition than in the well-watered plants. On the contrary to these statements the results in this study were different; the leaf and canopy spectral reflectance of sweet corn hybrids measured under low rain-fed (I 0 ) condition were lower than under optimal water supply condition (Table 1).…”

Transcriptomic Analysis of Female Panicles Reveals Gene Expression Responses to Drought Stress in Maize (Zea mays L.)

“…As a multidimensional stress, water limitation triggers a wide variety of plant responses; these range from responses at the physiological and biochemical levels to the molecular level [12][13][14][15][16]. When external drought stimuli are perceived and captured by sensors on cell membranes, the signals are transmitted through multiple signal transduction pathways.…”