Journal of Agriculture and Ecology Research International

Rice is a weak competitor against weeds and the majority of African farmers have few options and resources available for effective weed control. Weed control is one of the most important and suggestive practices for potential rice production. Field trials were carried out during 2017/2018 dry season at the Teaching and Research Fadama farm of the Kebbi State University of Science and Technology located at Jega (Latitude 12º21ˈN; Longitude 4º36ˈE) and that of Usmanu Danfodiyo University Sokoto located at Kwalkwalawa (Latitude 13º01ˈN, Longitude 5º09ˈE) to study the effects of integrated weed management (IWM) and variety on weed occurrence and the growth of rice. Both locations lie within Sudan Savanna ecological zone of Nigeria. The treatments consisted of six (6) weed management options (Solarization/Orizo-plus (3 WAT)/Hoe-weeding (6 WAT), Round-up/Orizo-plus (3 WAT)/Hoe-weeding (6WAT), Solarization/Hoe-weeding (3 WAT)/Hoe-weeding (6 WAT), Round-up/Hoe-weeding (3 WAT)/Hoe-weeding (6 WAT), Weedy-check and Weed-free) and three (3) rice varieties (Jamila, Faro 44 and Faro 57). The factorial combinations of the treatments were laid out in a randomized complete block design (RCBD) with the split-plot arrangement and were replicated three times. Weed management options formed the main plots while rice varieties were assigned to the sub-plots. The result of the study indicated that combination of solarization, orizo-plus and hoe-weeding achieved an effective weed control (33.56 g weed dry matter per m²) close to the weekly hoe-weeding (16.13 g weed dry matter per m²). Faro 57 variety was noted with the potential to increase rice growth under good weed management practices. From the results, it could be concluded that for increased rice growth, Faro 57 under the combination of solarization, orizo-plus and hoe-weeding IWM option should be adopted.

Field study was conducted at Humera, Kebabo, Banat, Zerbabit, Division and Ruwasa, western zone of Tigray, northern Ethiopia in 2018 under rain fed condition to determine effects of six nitrogen fertilizer levels (0, 11.5, 23.0, 34.5, 46.0 and 57.5 kg Nha^-1) applied in the form of urea and four spacing (30, 45, 60 and 75 cm) on growth and biomass yield of Mechello grass (Sorghum aethiopicum). The experiment was arranged in a split-plot design with three replications. Data on dry matter yield (DMY, tonha^-1), onset of flowering date (days), plant height (cm) and the number of tillers at harvest were recorded. A significant difference (p<0.001) due to nitrogen fertilizer was noted on DMY (tonha^-1), onset of flowering date (days) and plant height (cm) at harvest. Similarly, spacing had a significant effect on DMY (p<0.001), plant height (p<0.002) and the number of tillers at harvest (p<0.001). Higher values on DMY and plant height at harvest were recorded at 23.0, 34.5, 46.0 and 57.5 kg N ha^-1. Similarly, higher values of DMY and number of tillers at harvest were obtained from the denser (30 cm) and less dense (75 cm) spacing's, respectively. The study suggested that application of 23.0 kgNha^-1 and 30 cm spacing improved biomass yield of Sorghum aethiopicum under rain fed condition and recommended to be implemented. Therefore, application of 23.0 kgNha^-1 and 30cm spacing to boost biomass yield of Sorghum aethiopicum should be demonstrated and popularized in the study area and other similar agro-ecologies of the country.

Kenaf response to weed pressure depends on variations in morpho-physiological traits of genotypes. A study was conducted in Ibadan (7°38’ N 3°84’ E) Nigeria in the wet seasons of 2014 and 2015 to determine the response of kenaf genotypes to weed pressure. Twelve kenaf genotypes were planted in a conventionally prepared seedbed at 50 × 20 cm, in 5 x 5 m plot and arranged in an RCBD, replicated thrice. Initial weed flora composition revealed that Panicum maximum, Tithonia diversifolia, Mithracarpus viridis, Commelina spp, Aspilia africana, Tridax procumbens and Pennisetum purpureum were predominant in the experimental site. Kenaf plant height varied significantly and ranged from 30.53 cm to 59.73 cm and 60.67 to 76.80 cm at 6 weeks after sowing (WAS) in 2014 and 2015 respectively. Variation in plant height at 10 WAS did not follow the previous growth patterns in both years of the study. Stem girth at 10 WAS ranged from 1.26 cm (V₁-400-2) to 1.47 cm (A-60-282) in 2014. In subsequent year, Tianung had 1.47 cm stem girth as the thinnest, while Cuba 108 had the thickest stem (1.70 cm). Ifeken 400 (56.90 cm) and Cuba 108 (53.57 cm) had the broadest canopy width in 2014 and 2015 respectively, while A₂-60-28 (44.85 cm) and V₁-400-2 (41.33 cm) had narrowest canopy width in 2014 and 2015 respectively. Genotypes had comparable fibre yield, possibly due to catch-up growth from 8 to 10 WAS. Ifeken 400 (480 kg/ha) and Ifeken DI400 (550 kg/ha) had the highest seed yield in 2014 and 2015 respectively. These were similar with seed yield in other genotypes except V₁-400-2 (310 kg/ha) in 2014 and AC-313 (350 kg/ha) in 2015. However, seed yield reduction across genotypes ranged from 55 – 74%, with an average of 68% in both years when compared with the seed yield potentials of genotypes. Evidently, prolonged weed competition might have accounted for the seed yield deficit recorded in the study. Invariably, pre-emergence weed control only may not suffice for weed pressure in kenaf plot when seed production is of interest to the farmers. There was significant weed interference in plots sown to kenaf genotypes with low plant height and narrow canopy width. Consequently, high weed dry weight in V₁-400-2 (66.39 g/m²; 89.39 g/m²) might be responsible for seed yield penalty in both years of the study. Whereas, Ifeken DI400 had the least weed dry weight (25.93 g/m²; 26.92 g/m²) and comparable seed yield with the maximum in both years of the study. Genotypic variations in morphological and physiological traits might be responsible for responses to weed interference and crop performance. Early expression of weed suppressive traits evidently influenced genotypes-weed interaction.

Mungbean (Vigna radiata (L.) Wilczek) belongs to the order of Fabales, Faboideae sub family and Fabaceae or Leguminosae family. The field experiment was carried out in 2014-2016 main growing seasons at Humera and Kebabo with the aim of determining critical weeding period. The experiment was conducted in RCBD design replicated three times and consists of 15 treatments. The crop was kept weed-free for the first 10, 20, 30, 40, 50 and 60 days after sowing and then remained weedy till harvest or kept weedy for the same periods and then remained weed- free till harvest. Weed free and weedy treatments till harvest were included as controls for comparison. Mungbean variety of Arkeb was sown at a distance of plant to plant 5 cm and row to row 40 cm and the plot area was 10 m². The combine analysis of three winter seasons revealed that unrestricted weed growth significantly reduce yield of mungbean by 52% compared to completely weed free. Mungbean seed yield increased when the duration of weed infestation period decreased. Yield components such as number of pods per plant didn’t show significant difference, while number of seeds per pod and 100 seed weight shown significant difference. The critical weeding period for mungbean was 10-20 and 30-40 days after sowing.

The agricultural sector occupies an important economic and social position in Morocco. In this sense, in recent years our country has adopted a new strategy for the agricultural sector called the "Green Morocco Plan". This plan is based on two pillars, the first is that which provides agriculture with high added value, high productivity, and competitiveness, the second is that which offers solidarity-based agriculture, based on the fight against poverty, increasing the income of small farmers, particularly in disadvantaged areas (such as unfavourable stock areas, mountains or oases, plains and plateaus in semi-arid regions).

In our present study, we are particularly interested in the project to convert 760 ha of cereal crops into olive groves in the province of Tetouan. On the one hand, all stages of olive tree planting in cereal crops were monitored, as well as a comparison of yields, area, income, productivity and employment before and after the project was carried out. And on the other hand, an analysis of the various positive (social, economic and environmental) and negative (ecological) impacts of the project on the rural population in the province of Tetouan and on the environment in general. On the contrary, this project encountered several constraints, including natural, economic and social constraints.