Erick Amombo

Soil salinity limits forage productivity in ~1125 million ha of particularly arid lands across continents. Grass-legume mixtures are known to enhance soil nutrient cycling and forage productivity in non-saline conditions. We tested if these benefits can be replicated in the saline soils (EC_e > 14) of Laayoune-Morocco during the year 2021, based on a randomized complete block design (RCBD) experiment with 50–50 and 30–70% blue panicum grass (Panicum antidotales Reitz), alfalfa (Medicago sativa L.) mixtures compared to their monocrops. There was no significant variation (p = 0.36) in forage accumulation across treatment, but the blue panicum grass and alfalfa mixture had slightly greater forage yield compared to each in monocrop (13% and 5% Mg ha⁻¹). Blue panicum grass proportionate dry matter exceeded alfalfa in mixtures (62 and 54%). During establishment, blue panicum grass buffers against effects of high salinity on forage productivity in mixtures with alfalfa.

Root developmental plasticity might provide breeders with the opportunity to generate crops with more resistant root system designs to abiotic pressures such as salt stress. The potential influence of diverse root designs in a panel of sorghum varieties’ production and performance under salt stress was investigated in this study. Dry weight yield had a significant positive correlation with three root parameters: main root length, main root angle, and lateral root length. These root features have varying positive correlations with other salt tolerance indices. Interestingly, all root properties have a negative correlation with the electrolyte leakage. Except for the lateral root length, the negative correlations were significant in all other root features. This pattern holds true for other salt performance indices studied, such as total soluble sugar content, chlorophyll content, growth, and leaf area. Furthermore, there is an inter-variety variation in the contribution level of lateral root and main root length towards the total root length and this was found to influence yield and performance. These findings give a hint on the root architectural features that play a positive role in sorghum salt tolerance and improved forage yield.

Soil salinity and drought are the two major challenges agriculture is facing in marginal environments, such as desert areas, which limit the growth and productivity of traditional cultivated crop species. In the Sahara Desert of the southern region of Morocco, livestock is the major agricultural activity, and forage supply is severely affecting livestock production. Blue panicum (Panicum antidotale Retz.) is an alternative salt-tolerant crop recently introduced to Morocco’s Sahara to enhance forage availability for livestock. The aim of this study was to increase the productivity and nutritional quality of blue panicum through the use of integrated agronomic practices, such as planting methods (bed or flat), crop establishment (direct seeding, transplantation, and rhizome propagation), organic and/or mineral amendments, and grass–legumes intercropping. The preliminary results showed that in the highly saline conditions, the combined application of organic amendments, seedling transplanting, and bed planting method gave the highest production (56 t/ha/year) of fresh biomass, which is higher than 50% compared to the control. This study suggests that in the southern region of Morocco and the Sahara Desert, the adoption of the blue panicum with integrated agronomic practices sustains livestock production.