Agronomic characteristics of the Pennisetum glaucum submitted to water and saline stresses

Abstract

Agricultural production in semi-arid regions is limited due to water availability. In addition, the water quality available for irrigation is often compromised due to the high salt content present. Millet is a forage species considered tolerant to water deficit and moderately salt tolerant. In view of the above, the objective was to evaluate the growth of millet under water and saline stress associates. The experiment was carried out in a randomized block design, in a 4x3 factorial scheme, composed of four levels of water replacement, based on crop evapotranspiration (ETc): 25%.ETc, 50%.ETc, 75%.ETc and 100%.ETc and three levels of water salinity (0.03, 2.0 and 4.0 dS m-1). With 25%.ETc independent of salinity, all morphological characteristics of millet were affected, occurring death of plants in the initial growth phase. In the absence of salt and greater availability of water, greater plant growth occurred. With respect to salinity, there was a reduction in the increment of all variables evaluated, with the highest reduction at the highest saline level (4.0 dS m-1). Water and salt stresses, when associated, reduce the growth of millet, since concentrations above 2.0 dS m-1 and less than 50%.ETc compromise its full development, providing declines in yield.

Use of biostimulants in millet as strategies for tolerance to salinity of irrigation water

“…The NT in millet ranged from 2.91 tillers, in the condition of 1 dS m -1 with the control to 6.09 tillers in the treatment of 0 dS m -1 with the biostimulant (Table 1). These values are in agreement with the averages for the NT of millet found by other authors (Almeida et al, 2020;Costa, Domukoski, Ecco, & Duarte Júnior, 2014). Almeida et al (2020) in a study with the same climatic conditions and the same cultivar as the present research, under water and saline stress, found that irrigation of 100% of crop evapotranspiration and a salinity level of 4 dS m -1 provided average of 5.23 tillers per plant at 60 DAE.…”

“…These values are in agreement with the averages for the NT of millet found by other authors (Almeida et al, 2020;Costa, Domukoski, Ecco, & Duarte Júnior, 2014). Almeida et al (2020) in a study with the same climatic conditions and the same cultivar as the present research, under water and saline stress, found that irrigation of 100% of crop evapotranspiration and a salinity level of 4 dS m -1 provided average of 5.23 tillers per plant at 60 DAE. These same authors noted the increase in NT at the level of 4 dS m -1 up to 40 DAE, after this period there was a considerable reduction in the NT of millet with this level of salinity.…”

Green manure for soil salinity reclamation- A comprehensive review

“…Salinity of soil is considered one of the most detrimental abiotic stresses which affect plant morphology, physiology and biochemical metabolism that reduces plant growth and productivity (Malhi et al, 2021;Soltabayeva et al, 2021;Arif et al, 2020). A soil is grouped as under saline stress, when the electrical conductivity (EC) of the soil upsurges with salt concentration and that is when EC reaches ≥ 4 dS/m (Almeida et al, 2020). Salinity stress reduces leaf number and leaf area, crop growth and yield through nutrient imbalance, ion toxicity, osmotic imbalance, oxidative stress, reducing photosynthesis, altering gene expression and Nfixation (Desoky et al, 2020;Abdelaal et al, 2020b;Helaly et al, 2017;Hasan et al, 2017;Yan et al 2013).…”