Enhancement of seed germination rate and growth of Anagyris foetida L.

Bean trefoil (Anagyris foetida L.), the only species within the Anagyris genus (L.) of the Fabaceae family in Algeria, demonstrates considerable promise for reforestation actions in arid and semi-arid areas throughout the Mediterranean basin. Nevertheless, a prominent obstacle impeding the successful establishment of the species is the hardness of its seeds, resulting in reduced germination rates and inconsistent seedling emergence. The objective of this research is to improve seed germination and seedling development in A. foetida. A total of 750 pods were randomly collected from a population including 13 individuals. From this sample, 100 intact pods and 100 seeds were chosen for measurement and weight assessment. Three different scarification techniques were utilized as pretreatments: chemical scarification, involving varying durations of immersion in 98% concentrated sulphuric acid; thermal scarification, involving 24 hours of exposure to a water bath set at 35°C; and mechanical scarification, achieved through the use of abrasive paper. Each treatment comprised four replicates of 50 seeds, while untreated seeds were utilized as controls. Germination and initial seedling development were assessed after 30 days of cultivation. Statistical analysis revealed significant differences (p<0.001) among pretreatments concerning germination and seedling emergence. The highest germination percentages were observed following 120 minutes and 150 minutes of sulphuric acid soaking, with 86% and 91.5% of germination, respectively. The chemical pretreatments demonstrated correlations with shoot and root growth, as well as collar diameter. In contrast, the control group exhibited notably low germination (5.5%), while mechanical scarification resulted in a 55% germination rate. Seedling survival rates ranged from 93.7% to 99.4%. The seeds of A. foetida predominantly exhibit physical dormancy attributed to their hard and impermeable seed coat. These findings could be valuable for the generative reproduction of the species, especially for producing plants for afforestation/reforestation programs.