No abstract

Saffron (Crocus sativus L.) is cultivated in many countries for its culinary and medicinal values. The production of saffron is limited by several factors, including weed infestation, which causes damage to the crop in terms of quantity and quality. However, little information is available on the different weed management strategies for saffron cultivation, as most of the strategies implemented are developed for large-scale and conventional agriculture. As a result, they are not applicable or affordable for organic or smallholder farmers, as is the case for saffron cultivation. The objective of this study is to compare the effectiveness of plastic mulching versus mulching in controlling weeds in saffron cultivation in the eastern region of Morocco. During the trial, which was conducted in 2018, the parameters measured correspond, on the one hand, to morphometric measurements and determination of saffron stigma yield and, on the other hand, to the determination of density, dry biomass, and weed control capacity. Compared to the control, mulching reduced the population and dry biomass of the most formidable weeds such as Cynodon dactylon, Aster squamatus, Cyperus rotundus, and Convolvulus arvensis. The average stigmata yield from plastic mulch treatment was 9% higher than of the control, and the number of leaves, leaf area, number, weight, and percentage of daughter corms with large diameter were higher for plants grown under mulch. Overall, the results of this study showed that the use of PE (polyethylene) mulch effectively reduced weed populations and improved saffron yield and vegetative growth.

Saffron (Crocus sativus) has been an important medicinal plant since ancient times. This study aimed to seek the optimal light intensity for saffron growth by quantifying the effects of different shade levels on yield, vegetative growth, and weed development in the eastern region of Morocco. The plants were grown for 24 months in full sun (control) and 30%, 50%, and 70% shade. Overall, the results showed that shade positively affected the yield and vegetative growth parameters of saffron plants, with the highest yield (0.61 g/m2) and number of leaves (105 leaves/tuft) recorded when the plants were exposed to light shade (30%). The color of the leaves under the 70% shade levels was dark green. The results from the underground part showed that shade is positively correlated with the weight and diameter of daughter corms where the 70% shade recorded the highest values of weight (65 g) and percentage of large diameter corms (39%). As for weed density, this parameter was significantly affected by shade. The lowest weed density was recorded for the 70% shade treatment. In conclusion, 30% shade is suggested as optimal light irradiation for saffron cultivation.

Among all environmental factors, the temperature is considered one of the key elements that control the growth and development of saffron. This study was undertaken to investigate the effect of thermal forcing of corms on saffron growth and development. To this end, mother corms were collected at four different periods: late March (T2) , mid-April (T3) , late April (T4), and after leaf senescence (Control, T1) . The corms of each period were then pretreated at three successive temperature levels: at 25 °C for 2 weeks, at 15 °C for 2 weeks and finally at 4 °C for 12 weeks. The results showed that the thermal pretreatment of corms had a significant effect on some saffron parameters. The flowers of the corms that underwent thermal treatment were later than those of the control. Similarly, the flower numbers and stigma yield were negatively affected by thermal forcing of corms. Overall, the thermal forcing of corms under the proposed regime was unfavorable for the growth and development of saffron.

The turfgrass establishment is an important criterion for the choice of turfgrass species. The faster a lawn is established the more benefits it has to offer for landscapers. The objective of this work is to study the growth speed and development of six species. Four of them are cool-season ones (temperate): Lolium perenne, Festuca arundinacea, Agrostis stolonifera and Poa pratensis while the other two are warm-season ones (tropical): Pennisetum clandestinum and Cynodon dactylon. The species are seeded in two distinct periods: spring and autumn and are studied under the climatic conditions of the eastern region of Morocco which is characterized by a semi-arid Mediterranean climate with continental tendency known for its severe cold in winter. The coverage rate is the parameter considered in order to determine the duration of establishment for each species. The study was conducted in the experimental station of the Faculty of Sciences of Oujda. The results show that the establishment pace differs depending on the season and the nature of the species. Autumn is the suitable season for temperate species, while tropical species have shown a faster growth in spring. Lolium perenne and Cynodon dactylon are the fastest species to establish as they need a maximum of 30 days after the seedlings’ development. Poa pratensis is the last species to cover the total area seeded within 50 and 60 days during the two season’s spring and autumn respectively