The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to signific...The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to significant yield loss caused by several biotic and abiotic factors.Among these factors,one of the most important is the high weed pressure that ravages the upland rice ecology.In Nigeria,several independent weed control techniques,such as physical,chemical and cultural methods,have been recommended and adopted for weed control across varying rice upland ecologies.However,outcomes of these approaches when used independently have not consistently led to an increase in yield.There remains an outstanding deficit between the actual yield and the potential rice yield.This review aimed to identify potential research gaps,and quest effective and sustainable weed management strategies in smallholder upland rice farming systems in Nigeria.A critical analysis of studies suggests the potential of sustainable weed management practices if adopted and adapted smartly in different upland ecologies in Nigeria.Competitiveness of upland rice against weeds can be enhanced through strategic integration of weed competitive cultivars,optimum nitrogen application timings(within weed-free periods),uniform plant spacing,and high seeding rates,with conventional herbicide/manual weed control practices.However,such management practices can only be engaged where inputs are supplied on time and the technical know-how is extended to farmers.The review equally highlights potential research gaps for further studies.展开更多
With the aim of contributing to the solutions linked to the problems of the preventive preservation and the restoration of the Kasbah of Mehdia or the Kasbah of Moulay El Hassan, a study of the flora populating the fa...With the aim of contributing to the solutions linked to the problems of the preventive preservation and the restoration of the Kasbah of Mehdia or the Kasbah of Moulay El Hassan, a study of the flora populating the facades of these historical monuments was realized and showed the presence of a varied and diverse vegetation populating these buildings left to the ravages of time. The inventory of this flora showed the existence of 70 species among which 48were exclusively detected at the Kasbah of Mehdia, 11 other species were only discovered at the Kasbah of Kenitra and 11 vegetal species were inventoried at both Kasbahs. These plant species are divided into 28 families. Four families clearly dominate the flora inventoried at both Kasbahs of the Gharb region. These are the Asteraceae (15.7%),Poaceae (10%), Apiaceae (8.6%) and Scrophulariaceae (5.7%). These families alone account for 41.4% of the specific size of the flora of the studied sites. The most dominant vegetal type is the therophytes with 61.4% of the total specific size, followed by hemicryptophytes with 17.1%. Located at the top or the base of walls, these plants, fitting into joints or cracks, have a chemical action on the stones by acids which they release and also have a mechanical action on the stones by the growth of roots inside cracks. This vegetation remains one of the most important biological factors of the degradation of historical monuments.展开更多
文摘The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to significant yield loss caused by several biotic and abiotic factors.Among these factors,one of the most important is the high weed pressure that ravages the upland rice ecology.In Nigeria,several independent weed control techniques,such as physical,chemical and cultural methods,have been recommended and adopted for weed control across varying rice upland ecologies.However,outcomes of these approaches when used independently have not consistently led to an increase in yield.There remains an outstanding deficit between the actual yield and the potential rice yield.This review aimed to identify potential research gaps,and quest effective and sustainable weed management strategies in smallholder upland rice farming systems in Nigeria.A critical analysis of studies suggests the potential of sustainable weed management practices if adopted and adapted smartly in different upland ecologies in Nigeria.Competitiveness of upland rice against weeds can be enhanced through strategic integration of weed competitive cultivars,optimum nitrogen application timings(within weed-free periods),uniform plant spacing,and high seeding rates,with conventional herbicide/manual weed control practices.However,such management practices can only be engaged where inputs are supplied on time and the technical know-how is extended to farmers.The review equally highlights potential research gaps for further studies.
文摘With the aim of contributing to the solutions linked to the problems of the preventive preservation and the restoration of the Kasbah of Mehdia or the Kasbah of Moulay El Hassan, a study of the flora populating the facades of these historical monuments was realized and showed the presence of a varied and diverse vegetation populating these buildings left to the ravages of time. The inventory of this flora showed the existence of 70 species among which 48were exclusively detected at the Kasbah of Mehdia, 11 other species were only discovered at the Kasbah of Kenitra and 11 vegetal species were inventoried at both Kasbahs. These plant species are divided into 28 families. Four families clearly dominate the flora inventoried at both Kasbahs of the Gharb region. These are the Asteraceae (15.7%),Poaceae (10%), Apiaceae (8.6%) and Scrophulariaceae (5.7%). These families alone account for 41.4% of the specific size of the flora of the studied sites. The most dominant vegetal type is the therophytes with 61.4% of the total specific size, followed by hemicryptophytes with 17.1%. Located at the top or the base of walls, these plants, fitting into joints or cracks, have a chemical action on the stones by acids which they release and also have a mechanical action on the stones by the growth of roots inside cracks. This vegetation remains one of the most important biological factors of the degradation of historical monuments.
