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Harmful land snails and slugs are currently one of the most important threats facing agriculture in many parts of the world. Synthetic molluscicides are the main control method against these gastropods. However, dangers caused by these chemicals to the environment have led scientists to research for environmentally friendly alternatives. The objective of our work was to test and evaluate food pellets containing roots, stems, leaves or flowers of Euphorbia helioscopia against Theba pisana and Arion hortensis adults. Toxicity of the prepared pellets varied depending on plant organ and mollusc species tested. Pellets made of stems (LD50 = 1.35 g / 100 ml of agar at 2%) and leaves (LD50 = 1.39 g / 100 ml of 2% agar) proved more toxic to adult snails than those made of roots and flowers, which had no significant effects. In the case of slugs, pellets made of leaves (LD50 = 1.14 g / 100 ml of 2% agar) were more toxic than those made of stems (LD50 = 1.33 g / 100 ml of 2% agar), flowers (LD50 = 1.75 g / 100 ml of 2% agar) and roots (LD50 = 1.98 g / 100 ml of 2% agar). Compared to a synthetic product containing metaldehyde 5%, the results show that the use of these molluscicides derived from plants as pellets is environment- and healthconscious, targeted and economical. These products can be used in plant protection against phytophagous slugs and snails.

To develop eco-friendly alternative control strategies for medfly, mass trapping trials were conducted in the central Morocco during the crop season 2016. Two control methods, mass trapping and the attract-and-kill technique were compared for the control of medfly on two peach varieties ('Rome Star' and 'Ryan Sun') in Sefou district. For mass trapping, 62 traps/1.23 ha of MagnetTM Med type baited with ammonium acetate, trimethylamine, putrescine and 0.01 g of deltamethrin were installed on both varieties. In plots testing the attract-and-kill technique, treatments with malathion in mixture with protein hydrolyzate were applied to straw tuMs attached to branches of the same varieties whenever 1 fly was caught on a Trimedlure trap installed at the center of each plot. The results showed that the number of flies captured by mass trapping reached 508 and 489 adults on 'Rome Star' and 'Ryan Sun', respectively. The average number varied from 1 to 3 adults/trap/day, depending on the date of capture and the variety, and females accounted for 62-100% of total caught flies. In plots protected by the attract-and-kill technique, and taking into account the threshold adopted by the farm, 11 and 15 treatments were carried out respectively on the 'Ryan Sun' and 'Rome Star' varieties. Overall, infestation rates in plots did not exceed 0.3% before or at harvest with mass trapping versus 0.9% with the attract-and-kill technique. On fruit dropped on the ground, the infestation rate did not exceed 4% in mass trapping, compared to 11.5% in the chemically treated plots. Mass trapping was therefore proved to be an effective and eco-friendly tool for managing medfly on peach fruit.

The promotion of the agricultural production constitutes a main challenge for Morocco. This goal often results in an increased use of pesticides and fertilizers compromising soils and waters. Moreover, in addition to large stocks of pesticides, the invasion by locusts from southern countries requiring massive use of insecticides remains a potential threat for Morocco. Consequently, a continuous monitoring of the different environmental compartments (soil, water, and air) is increasingly needed for all the Moroccan territory Owing to hundreds of soil and water samples to control, it is important to develop simple and inexpensive methods to assess pollution levels by pesticides in agricultural soils and neighboring waters. The sophisticated chromatographic methods, in spite of their high accuracy, are very expensive and hardly accessible; they can be reserved for laboratory accurate analyses and statutory inspections. The purpose of this research is to palliate to this issue by developing a spectrometric approach for monitoring soils and waters; an approach which is effective, fast, easy to implement and reliable. In this sense, fluorescence spectroscopy presents a high potential owing to its high sensitivity, ease and rapidity. Total excitation-emission (TEEMs) and total synchronous fluorescence (TSFMs) mappings make it possible to detect remains of fluorescent pesticides in soils or waters. The present investigation aims at the creation/extension of a total excitation-emission and total synchronous fluorescence mapping database to fingerprint those fluorescent pesticides in large use in Morocco. These fluorimetric fingerprints must allow the direct identification of any targeted fluorescent pesticide persisting in soil or water. After a large survey among farmers and agricultural product distributors, to target the best-selling and most used pesticides in different Moroccan regions, one hundred and five (105) pesticides have been fingerprinted. Applicability tests were carried out on the basis of field pre-surveys information and total fluorescence results. In the present work, the maps and synchronous spectra of a set of 57 commercial pesticides are reported. Moreover, four examples of TEEMs/TSFMs fingerprinting applications to recognize pesticide remains in soil samples are shown. The agricultural plantations monitored are located in the great agricultural region Doukkala at the western Atlantic side of Morocco. The catalogue has been enriched by a PCAbased statistical study to constitute groups of pesticides with similar spectrometric fingerprints. The emitting similarity inside pesticide groups, despite different active principles, was explained by similarity of formulation products. The implemented spectrofluorimetric approach is satisfying and seems suitable, at least, as a warning method in case of massive contamination of soils or waters. [ABSTRACT FROM AUTHOR]