Comprehensive analysis and implications of Veronica persica germination and growth traits in their invasion ecology.

Invasive alien species implications in ecological threats are attributed to their unique characteristics that are linked to their invasion. Veronica persica (Plantaginaceae family) is an alien weed species in Egypt. Regardless of its widespread globally in various regions, the growth traits and behavior of V. persica remain poorly understood. The comprehensive analysis, reveals the optimal germination (Gmax) was detected at 10/20 °C, 15/20 °C, and 20/25 °C at the moderate temperature regimes. The rapid germination rate (G rate) peaked at 10/20 °C regime, with a rate of 0.376 per day. Furthermore, under stress conditions, V. persica has 50% germination inhibition (G50) and 50% of growth inhibition occurred at - 0.91 MPa and 0.75 MPa of osmotic pressure and 3225.81 ppm and 2677.1 ppm of salt stress (NaCl) respectively. The germination ranged from 6 to 9 pH, with the highest germination percentage occurring at a pH of 7 & 8, reaching 88.75% compared to the control group. There is a strong interaction effect between habitats and plant stages, the plant stages and habitats have significant effects (p ≤ 0.00) on V. persica growth. There was high and moderate plasticity in the response of morphological and growth features between stages. During the seedling-juvenile interval and the juvenile-flowering stages, respectively, there was a noticeable increase in both Relative Growth Rate and Net Assimilation Rate. Demographic surveys identified approximately 24 species across 11 families associated with V. persica in invaded areas. The Sorenson indices of qualitative index exhibited high similarity values in the invaded sites by (82.35%) compared to (72.72%) in non-invaded sites. However, interactions with native communities were reflected in lower richness, diversity, and evenness, displaying slightly higher Simpson index 1 (λ) values compared to invaded and non-invaded sites (0.043 and 0.0290) vs. (0.0207 and 0.268), in rangelands and F. carica orchards respectively. These results emphasize the substantially higher adaptability of V. persica to variable environmental conditions and abilities to invade a new community. This knowledge about invasive V. persica weeds germination and growth is itemized as the consistent predictive base for future invasion and informs strategic management priorities.

Priming of Citrullus lanatus var. Colocynthoides seeds in seaweed extract improved seed germination, plant growth and performance under salinity conditions.

Citrullus lanatus var. Colocynthoide "Gurum" is an unconventional crop that can be utilized as a new source of edible oil and has the ability to grow in a variety of harsh conditions. To mitigate the adverse effects of salinity on seed germination and plant performance of C. lanatus, seeds were primed in the aqueous extracts of the seaweed Ulva lactuca before planting under greenhouse conditions. The aqueous extract of U. lactuca at 8% w/v led to maximal seed germination percentage and seedling growth of C. lanatus. Moreover, U. lactuca extract counteracted the negative effects of salt stress on the plant by significantly increasing the activity of SOD, CAT, and POD. The bioactive components of U. lactuca, e.g. glycine betaine and phenolic compounds can account for such beneficial role of algal extract on C. lanatus. Thus, priming of C. lanatus seeds in U. lactuca extract with various concentrations of U. lactuca extract can be employed as an effective practice for successful seed germination, improved plant growth and enhanced salt resistance, probably as a result of increased antioxidant enzymes activity and photosynthetic pigments.