Longevity of leaves directly influences grain yield of wheat (Triticum aestivum L.), but is greatly diminished by environmental stresses. The objective of these studies was to identify treatments that might delay senescence of wheat leaves and increase grain yield. ‘Nesma’ wheat was grown on a heavy clay soil at Meknes, Morocco, for two seasons, the first characterized by mild stress and the second by more severe stress from inadequate precipitation and high temperature. Three planting dates, two seeding rates, and foliar applications of NH4NO3, and KH2PO4 in randomized complete block designs were tested for efficacy in delaying senescence of leaves as measured by proteolytic activity, chlorophyll and protein concentrations, and grain yield. Advancing the planting date from early December, the optimum time, to November in the first year and delaying planting until January in the second year reduced grain yields in both seasons. Increasing the seeding rate from 200 to 400 kernels in m‐2 increased grain yields only in the second year, and foliar applications of 10 kg N as NH4NO3 ha−1 were ineffective in both years. Foliar applications of 5 to 10 kg ha−1 KH2PO4, in contrast, often increased grain yields by 1 Mg ha−1 or more. Senescence processes were enhanced by late planting because of high temperatures during maturation and by dense seeding because of interplant competition. Treatments that increased grain yields usually slowed senescence processes. Applying dilute solutions of KH2PO4 was most effective and, after further testing, might have merit for wheat in regions where drought and high‐temperature environmental stresses occur.

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This study investigated the response of corn silage to different combinations of zinc (Zn) and phosphorus (P) soil supply when grown in sandy soil. The soil was naturally poor in extractable Zn and rich in plant-available P. The experiment was conducted in outdoor containers. The treatments consisted of soil supply combinations of 3 levels of Zn (0, 5 and 10 mg Zn kg −1 of dry soil) and 4 levels of P (0, 12, 36 and 72 mg P2O5 kg −1 of dry soil). The results showed the absence of a significant effect (at p ≤ 0.05) of Zn-P interaction on plant growth, plant mineral content or total aerial dry weight at harvest. P application depressed Zn shoot content, and conversely, Zn supply slightly reduced P shoot content. The total aerial dry weight at harvest was not enhanced by P application. However, it was significantly increased by Zn supply of 5 mg·kg ) application (at p ≤ 0.05). This increase was around 15% compared to no Zn soil supply. It was especially linked to kernel dry weight and particularly to pollination rate. For the highest level of P supply, Zn applications significantly enhanced (at p ≤ 0.05) the kernel dry weight and the pollination rate by 22.1% and 38.4% respectively, compared

The objective of this study is to identify an adequate zinc (Zn) foliar spray concentration which corrects Zn deficiency without disrupting other plant mineral contents, enhances plant growth, and thereby corn silage yield when grown on sandy soil. A field experiment was conducted using five Zn foliar spray concentrations (w/v): 0.03%, 0.07%, 0.10%, 0.14% and 0.18%. Zn sulfate (ZnSO 4 . 7H 2 O) was used as a source of Zn. Zn foliar application was realized at two growth stages (6-7 and 9-10 leaf stages). A treatment without Zn foliar spray was maintained as control. The results showed a quadratic response of corn silage towards Zn foliar spray concentrations, in which 0.09% was the optimum value for overcoming Zn deficiency. Such level increased shoot Zn concentration at harvest from 15 mg kg -1 to 21.8 mg kg -1 , didn't decrease plant mineral content below critical levels, enhanced plant growth and raised silage yield by 49.4% compared to control. On the other hand, Zn foliar spray concentration up to 0.10% induced visible leaf damage, growth inhibition and a decrease of 26% in silage yield compared to Zn foliar applications at 0.09%.

By the diversity of its soil and climatic factors, Morocco offers a flora particularly rich in aromatic and medicinal plants (MAP). In order to obtain the most information about the flora (flowering times, fruiting, harvesting and their main uses in traditional medicine), a study was conducted in the mountainous Khenifra region. A survey of users of MAP (rural population, herbalists arborists) has been undertaken and was completed by field observations and sampling at different stages of growth. The results showed a range of indigenous and diversified MAP belonging to 10 botanical families (Lamiaceae, Asteraceae, Rosaceae, Chenopodiaceae, Papaveraceae, Caryophyllaceae, Cupressaceae, Rutaceae, Anacardiaceae and Zygophyllaceae). The flowering period of all species, according to the local community surveyed, spread from February (2%) to September (12%), with a significant concentration from April to June (65%).The highest rate of fructification occurred in June-July (64%). The harvesting period of the main MAP from this mountain area stretches mainly from March to April (61%). The mode of propagation stated varied among species, and concerned mainly replication by seeds (53%) and cuttings (24%). Regarding the use of these indigenous MAP as traditional medicines, all plant parts are used, especially leaves, flowers and stems.