References of "El-Mejjaouy, Yousra"
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See detailChlorophyll a fluorescence in response to phosphorus deficiency and heat stress
El-Mejjaouy, Yousra ULiege; Zeroual, Youssef; El Gharous, Mohamed et al

Poster (2020, January 31)

Photosynthesis and particularly photosystem II (PSII) is considered sensitive to high temperature. Our main objective in this study is to understand the role of phosphorus in heat treatment effects ... [more ▼]

Photosynthesis and particularly photosystem II (PSII) is considered sensitive to high temperature. Our main objective in this study is to understand the role of phosphorus in heat treatment effects alleviation in tomato plant. In this work, the influence in three levels of phosphorus concentration (15, 31 and 60 ppm) assured by two forms of fertilisers (Mono-Ammonium Phosphate (MAP) (11-52-0) and NPK (15-15-15)) on tomato plants growth and heated-leaves treatment responses was investigated. Tomato plants were grown in hydroponic conditions and the effects of different P levels in change of chlorophyll content index, leaves dry weight and total P in root and shoot ratio were analysed. Results present that plants grown in low phosphorus concentration in hydroponic medium showed a decrease in chlorophyll content index, leaves dry weight and total root P/total shoot P ratio. Furthermore, heat treatment at 40 °C for 30 min significantly affects chlorophyll a fluorescence transient shape and photosynthetic performance index parameter (PIABS). We observed that the two forms of fertilisers positively alleviated the detrimental effects of high temperature on leaves of plants grown at high level of phosphorus. According to these results, the role of phosphorus in the alleviation of the effects of temperature on the electron transfer chain is observed. However, the mechanism by which P acts in this protection remains unclear. It is possible that P has a significant action at the level of the PSI, but further studies are necessary to elucidate the direct or indirect actions of P in this heat effect alleviation. Also, a combined action of P, N and other mineral elements is very likely in this protection against the negative effects of high temperatures. [less ▲]

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See detailUse of precision farming practices and crop modelling for enhancing water and phosphorus efficiency
El-Mejjaouy, Yousra ULiege; Mamassi, Achraf ULiege; Chtouki, Mohamed ULiege et al

Poster (2019, October 07)

In a context of climate change, African agriculture aims at developing new approaches to face multiple constraints related to water scarcity, soil degradation or nutrients depletion. Nonrenewable ... [more ▼]

In a context of climate change, African agriculture aims at developing new approaches to face multiple constraints related to water scarcity, soil degradation or nutrients depletion. Nonrenewable resources such as phosphorus are of concern. Precision farming, as a new alternative to conventional agriculture, aims to improve crop productivity through the optimization of water and nutrients use efficiency. It considers the spatiotemporal variability of fields related to soil heterogeneity, plant nutrient needs and meteorological conditions through the growing season. For an effective management of soil and crop system, several new technologies have emerged, including soil-plant sensing, innovative crop management practices, and crop growth simulation and yield forecasting models. Regarding phosphorus management, use efficiency can be improved through the accurate assessment of phosphorus status in soil and plant. Proximal sensing based on visible near-infrared spectroscopy seems to be a promising alternative to manage soil fertility, understand phosphorus dynamics and enhance crop productivity. These aims can be also achieved by adopting hyper-frequent drip fertigation as an efficient agricultural practice, combined to hydrogeophysics to monitor water and nutrient fluxes in the soil-plant continuum. In addition, based on the interactions between meteorological conditions, soil properties and crop management, the use of agrometeorological models in simulation of crop growth parameters and forecasting crop production levels may allow assessing soil fertility and potential, ensuring an optimal future exploitation of farmland through the improvement of fertilization practices in an integrated management cropping system. [less ▲]

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