## 4 Discussion  
Biological formulations are becoming increasingly popular due to their potential to offer effective and environmentally friendly alternatives to chemical pesticides [38]. These formulations use natural ingredients, such as essential oils, to protect crops from pests and enhance their growth [39; 40]. In this study, we explore the potential of a formulation of _P. hulepensis_ essential oil and phosphogypsum (EO-PG) as a biological formulation with high biological value. The EO-PG formulation was prepared by fixing the EOPH onto the porous material of PG. The essential oil was characterized by GC-MS, which identified a composition of seven molecules, with \(\alpha\)-pinene being the major compound at 88.62%. In fact, several authors have studied the compounds profile of genus Pinus essential oils. From their results, it appears that a high percentage of \(\alpha\)-pinene is characteristic of most of this essential oil, except in the case of the essential oil of _P. heldreichii_ and _P. roxburghii_[41]. For the essential oil of _P. heldreichii_, limonene is the majority constituent at 79.44% [42], and for the essential oil of _P. roxburghii_, \(\delta\)-3-carene represents 50.6% [43]. Other studies have shown that the oils richest in \(\alpha\)-pinene are those of _P. wallichiana_ (90.7%) [44]. The essential oil of _P. halepensis_ is distinguished by a lower content of \(\beta\)-pinene compared to that of _P. pinaster_, with levels of 1.08% and 6.35%, respectively [45]. This constituent presents higher contents for the essential oils of French and Portuguese _P. pinaster_, with respective levels of 17% and 26% [46]. Phosphogypsum was also characterized and found to be a porous material containing a high percentage of calcium sulfate dihydrate (CaSO\({}_{4}\cdot\)2H\({}_{2}\)O) and a minor percentage of quartz. The EO-PG formulation showed a higher level of insecticidal activities than the essential oil alone against the pest _Bruchus signaticornis_ of lentils. This can be explained by the desorption of the essential oil after its fixation on PG, which plays a role in the retention of the molecules. This retention allows for the sustained release of the essential oil and a longer-lasting effect on pests. The EO-PG formulation also had a positive effect on germination. This can be attributed to the phosphorus element in phosphogypsum, which has been shown to have a beneficial effect on plant growth. This indicates that the EO-PG formulation has potential as a growth-promoting agent as well as a pest control agent. Optimal levels of parameters such as temperature, humidity, and concentration are critical for achieving effective insecticidal activity and controlling insect populations. These  
Figure 9: Correlations between diffusion parameters of EO–PG and biological parameters. parameters should be carefully considered during the development of insecticidal formulations. Overall, the results suggest that the EO-PG formulation has the potential to be an effective and eco-friendly insecticide. However, further research is required to establish the optimal conditions [38]. The higher percentage of germination observed in the EO-PG treatment suggests that the addition of phosphorus through the EO-PG formulation may have contributed to improved germination compared to the control and EOPH treatments. It is important to note that the concentration of the EOPH and EO-PG treatments can affect their efficacy. The results of this study suggest that the EO-PG treatment with a concentration of 0.01 uL-g-1-cm\({}^{-3}\) was the most effective in promoting lentil seed germination. However, additional research is required to validate these findings and establish the ideal concentration of the EO-PG mixture for enhancing the germination process in lentil seeds [47]. The flux \(F\), an important parameter for understanding the desorption phenomenon, was optimized using design plans. The results showed that temperature, humidity, and concentration all had a significant effect on this parameter.