Evaluating Structural, Chlorophyll-Based and Photochemical Indices to Detect Summer Maize Responses to Continuous Water Stress

Abstract

This study evaluates the performance of structural, chlorophyll-based, and photochemical indices to detect maize water status and to assess production based on five years of field experiments (2013-2017) during the primary growth stages. We employed three categories of indicators, including water condition and productive and thermal indicators, to quantify the responses of summer maize under continuous water stress from drought to waterlogging conditions. Furthermore, we adopted several spectral indices to assess their sensitivity to three categories of metrics. The results showed the association is the best between the treatment level and Leaf Water Content (LWC). The waterlogging treatment influenced Leaf Water Potential (LWP) in moderate drought stress. Severe drought stress caused the strongest reduction in productivity from both Leaf Area Index (LAI) and chlorophyll content. In terms of sensitivity of various indices, red-edge-position (REP) was sensitive to maize water conditions LWP, LAI and chlorophyll content. Photochemical Reflectance Index (PRI) and Normalized Difference Vegetation Index (NDVI) were the most and second most sensitive indices to productive indicators, respectively. The results also showed that no indices were capable of capturing the information of Crop Water Stress Index (CWSI).

Water stress effect on agro-morphological and physiological parameters of three local cultivars of maize (<i>Zea mays</i> L.) of South Benin

“…This situation combined with transpiration loss of water would force plants to reduce their leaf area to adapt to the water conditions imposed on them. A sharp reduction in leaf growth parameters including width, length and leaf area of maize was obtained under water stress conditions (Avramova et al, 2016;Li et al, 2018). Or the intercepted radiation proportion is estimated from the leaf area which is therefore an important variable in crop production determination.…”

“…Indeed, a decrease in chlorophyll content was observed in corn under water stress conditions compared to non-stress. (Avramova et al, 2016;Ahmad et al, 2017;Li al., 2018). On the other hand, Adra (2010) found an increase in total chlorophyll content and Amoumen et Benhebireche (2013) obtained decrease in chlorophyll content in water stress conditions in durum wheat.…”

Understanding Vine Hyperspectral Signature through Different Irrigation Plans: A First Step to Monitor Vineyard Water Status

“…On another level, the Red-Edge domain also seems to be of particular interest. This domain gives insight into leaf chlorophyll concentration [62,68,69], which is itself related to the availability of water in the plant [70][71][72]. The "Red-Edge" domain has already been linked to the water status of the vine by [20], who estimated crop coefficient (Kc) using a time series of Sentinel-2 images, or by [73], who correlated stem water potential and UAV data.…”

Hyperspectral and Thermal Sensing of Stomatal Conductance, Transpiration, and Photosynthesis for Soybean and Maize under Drought

“…Moreover, structural related VIs such as NDVI, rNDVI, OSAVI, EVI, and REIP showed significant effects between soil water levels (Table 4) and significantly positive relations between these VIs with g s and T r (Figure 6 and Figure S4). In recent studies, structural VIs have also successfully been used to predicted water stress proxies (e.g., g s , leaf water content, and leaf water potential) in maize plants [91,92]. In our study, the effect of growth through these VIs is shown by the high sensitivity of phenology (DoM), lack of significance with soil drought (WHC) (Table 4), and the strong positive correlations with h c (R 2 > 0.86) (Figure 6 and Figure S4).…”