The cocoa tree (Theobroma cacao L.) is a tropical plant of the Malvaceae family whose cultivation is for the production of beans mainly intended for the chocolate industry. In Côte d’Ivoire, cocoa cultivation is of paramount importance as it is the pillar of the Ivorian economy. Indeed, cocoa accounts for 30% of the gross domestic product (GDP), more than 50% of export earnings, and 2/3 of the direct or indirect jobs of the Ivorian population [1] . In addition, with an estimated production of 2.23 million tonnes during the 2021-2022 season, the country is the leading producer of marketable cocoa [2] .

In cocoa farming, a good yield implies the application of phytosanitary products [3] . As a result, in addition to fertilizers, a wide range of pesticides are used to reduce the impact of biotic constraints [4] . Among these factors, weeds require special attention as they are one of the main biotic constraints behind the decline in crop system production [5] . Indeed, weeds have a negative impact on cocoa production depending on whether they compete with cocoa trees for water and mineral resources in the soil [5] or are vectors of pathogens [3] [6] . To curb the proliferation of these sometimes very aggressive weeds, chemical or mechanical weeding is carried out by producers [7] . However, with the arduousness of manual weeding combined with the scarcity of labour, the use of synthetic herbicides is becoming more and more widespread and is even the preferred means of weed control for producers [8] . However, several studies agree that the repeated use of herbicides, in addition to being harmful to crops, negatively affects human and animal health and the environment [9] . For example, N’guessan et al. [10] recorded a very high content of glyphosate and cadmium in giant African snails belonging to the genus Achatina, which are nevertheless very popular with African populations and those of Côte d’Ivoire in particular. Blé et al. [4] also indicated that in the Soubré area, Côte d’Ivoire, the pesticides used have a negative impact on soil water. With regard to the health of cocoa farmers, non-compliance with good practices for the use of herbicides due to their low level of education associated with the dangerousness of the active ingredients, Glyphosate and Paraquat, recommended herbicides, constitute real risks [11] .

Despite the pressure exerted by these weeds on crops, Touré et al. [12] stressed that the presence of certain species does not necessarily imply the existence of a potential danger to agrosystems and may even be beneficial for the crop. Based on this observation, studies have been carried out to identify weeds and at the same time their degree of infestation in order to achieve integrated management [13] [14] . This is how Amba et al. [15] classified the weeds found in a cocoa plantation in Ivory Coast into non-aggressive, slightly aggressive and very aggressive species in order to optimize the use of herbicides. This research fits perfectly into the current development programs of agricultural countries such as Ivory Coast where a compromise must be found between agricultural production and environmental protection [16] [17] . Indeed, the new environmental policy placed under the aegis of the Ministry of Health, Environment and Sustainable Development (MINSEDD) advocates more sustainable cropping systems, with low use of synthetic inputs that are more favourable to the protection of the environment and the safeguarding of biodiversity. Thus, the systematic elimination of all herbaceous flora by these chemical treatments is therefore an obstacle to sustainable cocoa production, especially since some have symbiotic relationships with arbuscular mycorrhizal fungi (AMF) which are favourable to plant growth [14] . Mycorrhizal symbiosis is a symbiotic relationship between fungi and plant roots from which they exchange nutrients [18] . Through this mutually beneficial association, the fungus, thanks to its network of extra-root hyphae that extends well beyond the soil area explored by the roots, improves the mineral nutrition of plants [19] . In addition, the mycelium of arbuscular mycorrhizal fungi often connects two or more plant individuals of the same or different species establishing arbuscular mycorrhizal networks [20] . This results in a long-distance transfer of nutrients through this network that promotes plant coexistence [21] . Compared to the cocoa tree, in addition to being 23% mycorrhizal [22] , it benefits from a significant effect of this symbiosis on its growth [23] .

In relation to herbaceous weeds, some of them, because they are highly mycotrophic, are likely to promote the population of arbuscular mycorrhizal fungi [24] . In addition, some weeds, in this case Fabaceae, have the ability to fix atmospheric nitrogen and fertilize the soil thanks to the presence of root nodules [25] . Just like the practice of agroforestry, whose benefits on the sustainability of cocoa production have been documented in in-depth studies [26] , the management of herbaceous plants could also be considered [8] .

This study aims to contribute to the sustainability of cocoa production in Côte d’Ivoire through a reasoned management of herbaceous weeds. Specifically, the aim was to: (i) identify the dominant herbaceous weeds on cocoa plantations, (ii) determine the physicochemical parameters of the soils of these plantations, (iii) assess the level of endomycorrhizal colonization of dominant herbaceous weeds, and (iv) quantify the spore density of arbuscular mycorrhizal fungi in soils collected under herbaceous plants.

In both food and perennial crop plantations [11] , several weeds are commonly encountered and these have a negative impact on agricultural production [5] and the establishment of forest plantations [30] . In this study, the prospection made it possible to identify 14 major species in the cocoa fields in the localities of DJELEBOUE, GNAKPALILIE and DIEKOLILIE. These species are divided into 12 families, the most prominent of which are the Poaceae and the Euphorbiaceae. These results are in line with those of Amba et al. [15] who reported a high proportion of weeds belonging to the Poacacian family in a cocoa field in Adzopé, Côte d’Ivoire. However, the species judged by Touré et al. [12] as well as with high infectivity and highly damaging to crops such as Chromolaena odorata and Euphorbia heterophylla are absent.

The results also revealed the presence of traces of mycorrhizal symbiosis, in this case arbuscles, hyphae, spores and vesicles in the roots of the weeds encountered. These structures observed in the roots of forest trees [31] and edible herbaceous plants [13] and weeds [32] attest to the association of these herbaceous weeds with arbuscular mycorrhizal fungi. In addition, out of 14 species, 12, or 85.71% of herbaceous weeds, are mycorrhizae. This value confirms the writings of Smith et al. [33] , according to which 80% of plant species accept this symbiosis. The presence of these species could be beneficial to cocoa trees because the mycelial filaments of these non-specific fungi are able to spread in their root system [34] . In addition, the species Parietaria officinalis, which has been most intensely mycorrhizal, is not very aggressive [15] . In addition to having enormous medicinal properties, according to Lambion and Amour [35] , it would be of great use in agroecology because it could compete with more harmful weeds and reduce the pressure of bed bugs. Indeed, the sciophytic character of this species, associated with its rapid growth, will promote its propagation, thereby reducing the development of other weeds. Furthermore, the results confirm the non-mycorrhizal status of species belonging to the families Commelinaceae (Polia japonica) and Cyperaceae (Cyperus difformis) established in the literature [36] .

The importance of cocoa farming in the Ivorian economy is the result of the convergence of various pedoclimatic and vegetation factors. Thus, the soils of Lakota plantations have this characteristic. However, a dynamic seems to be apparent at the level of these parameters from one locality to another as well as observed for the organic matter content and the pH. Moreover, this result is closely related to that of Amani et al. [22] ; the latter having obtained physico-chemical parameters that change from one agro-ecological zone to another while remaining above the fertility threshold. Relative to acidic Ph, the values are close to those of Aikpokpodion et al. [37] . This acidification of cocoa plantations can also be attributed to a high use of pesticides over a long period of time, as demonstrated by the latter.

In these soils, the average spore density of arbuscular mycorrhizal fungi was 4.29 spores. G-1 with a maximum of 6.53 and a minimum of 1.45. These values are close to those observed by Amani et al. [22] in cocoa plantations but significantly lower than that obtained from Voko et al. [38] in cassava fields. This difference can be attributed to cultural practices that differ from one crop to another. Indeed, the cultivation of cassava requires fewer phytosanitary treatments compared to the cocoa tree; therefore, soil mycorrhizal fungi are prone to a small decline in their community. Thus, the low population of microorganisms can result either from the stability that prevails in the environment, such as the forest [39] or also from the use of pesticides [37] . Also, it is only in the cocoa fields of DJELEBOUE and GNAKPALILIE where the spores were more abundant, that the three most mycorrhizal species, namely Rottboellia cochinchinensis, Panicum cappillare and Parietaria officinalis, were identified. This suggests that they are favorable to the fertility of the environment. Indeed, according to Oehl et al. [40] , mycorrhizal fungi are bioindicators of soil fertility.

This study was undertaken to evaluate the endomycohizial status of the dominant herbaceous weeds in the cocoa plantations of the localities of DJELEBOUE, GNAKPALILIE and DIEKOLILIE. A population of 14 species divided into 12 families has been identified. Of these species, 12 out of 14 are mycorrhizal, i.e. 85.71%. In these localities, the average density of arbuscular mycorrhizal fungal spores per gram of soil was 4.30.

At the end of this study, it appears that the benefits inherent in the maintenance of certain mycotrophic and non-aggressive herbaceous weeds such as Parietaria officinalis can be considered in two points: (i) improvement of the fertility of cocoa plantations as well as of the mineral and water nutrition of cocoa trees, and (ii) reduction of pressure of invasive herbaceous weeds.