Selección de las semillas : Algunos consejos prácticos

La abundancia de las cosechas depende mucho de la naturaleza del suelo, de su preparación mecánica y química y del clima; pero la buena elección del reproductor decide á menudo del éxito del cultivo. Se comprende cada día mas toda la autoridad de este principio: Tal grano, tal producto. Desgraciadamente, se encuentran agricultores poco cuidadosos de sus intereses, que compran sus granos al acaso, sin preocuparse en lo mas mínimo de su origen y cualidades. Se ignora á menudo, que el empleo de una mala semilla puede comprometer toda la cosecha, y que uno de los signos mas carácterísticos del cultivo rutinario, es la indiferencia por la calidad de las semillas. Solamente deben emplearse los granos mas perfectos, en su especie y variedad, es decir, los que han llenado todas sus fases de vegetación en las condiciones mas favorables.Facultad de Ciencias Agrarias y Forestale

Selección de las semillas : Algunos consejos prácticos

La abundancia de las cosechas depende mucho de la naturaleza del suelo, de su preparación mecánica y química y del clima; pero la buena elección del reproductor decide á menudo del éxito del cultivo. Se comprende cada día mas toda la autoridad de este principio: Tal grano, tal producto. Desgraciadamente, se encuentran agricultores poco cuidadosos de sus intereses, que compran sus granos al acaso, sin preocuparse en lo mas mínimo de su origen y cualidades. Se ignora á menudo, que el empleo de una mala semilla puede comprometer toda la cosecha, y que uno de los signos mas carácterísticos del cultivo rutinario, es la indiferencia por la calidad de las semillas. Solamente deben emplearse los granos mas perfectos, en su especie y variedad, es decir, los que han llenado todas sus fases de vegetación en las condiciones mas favorables.Facultad de Ciencias Agrarias y Forestale

Résumé des résultats des enquêtes de base niveau ménage : site de Tougou, Burkina Faso

Ce rapport présente les résultats des enquêtes de base conduites au niveau des ménages de sept (7) villages du site de Tougou (Burkina Faso) dans le cadre du programme de recherche du CGIAR sur le Changement Climatique, l’Agriculture et la Sécurité Alimentaire. L’objectif de ces enquêtes était de de collecter toutes les données et informations sur des indicateurs clés de base concernant les ménages notamment les moyens de subsistance, l’agriculture et la gestion des ressources naturelles, les besoins d’information sur le climat et la gestion des risques, et les pratiques d’atténuation et d’adaptation

Environmental fragility in the Sahel

A companion to the OECD States of Fragility 2022 report, this paper analyses the drivers and effects of climate and environmental risks in the Sahel,focusing on increasing food insecurity, rapid urbanisation and intensified mining. It outlines options for improved policy responses by providers of development co-operation

Proliferation of the water hyacinth (Eichhornia crassipes) on the river Sô (Sô-Ava) in Bénin

Water hyacinth is a plant from America which was imported in Africa as an ornamental plant but because of its proliferation, has become a dangerous aquatic macrophyte. In Benin, it colonizes most courses in continental water. Water hyacinth is present in several areas of the world as an ornamental plant and its infestation can be controlled by several treatments. The objective of this work is to identify them and promote their valuation in order to reduce their dangerousness to the population of aquatic organism as well as their ecosystem. In this regard, a survey was carried out to overcome these problems the people of the town in Sô- Ava and around face every year on the Sô River flows into Lake Nokoue. The coverage of the water hyacinth (Eichhornia crassipes) is a major problem for people living in those areas where the plants rage. This plant prevents the movement of motorized boats, prevents the penetration of oxygen in water, which greatly reduces the number of organism such as fish fry, crocodiles nest and boas.© 2015 International Formulae Group. All rights reserved.Keywords: Eichhornia crassipes, Sô river, aquatic weed, biological contro

Local, Seasonal, and Yearly Condition of Juvenile Greenland Halibut Revealed by the Le Cren Condition Index

An understanding of biological characteristics, such as growth patterns, condition, and energy reserves, is important for better understanding the environmental constraints exerted on fish populations. This is especially true for exploited fish stocks in the current context of climate change. Using biological data collected from 2006 to 2009 during bottom trawl research surveys by Fisheries and Oceans Canada in the estuary and Gulf of St. Lawrence (EGSL) as well as data from 2000 to 2018 in the northwest Atlantic, we sought to improve our knowledge on the seasonal condition of Greenland Halibut Reinhardtius hippoglossoides juveniles and to better understand the divergence in some life history traits between juveniles captured in these two regions. We validated the use of the Le Cren condition index and evaluated its relationship with energetic status in juvenile (20–32-cm TL) Greenland Halibut. In the EGSL, juvenile condition was higher in winter and spring compared to summer and fall. Such variations may result from this species’ pelagic predation activity and prey availability. Juveniles captured in the EGSL during 2016–2017 were larger but had a lower condition index than those captured in the northwest Atlantic, but we found no indication of earlier sexual maturation in the EGSL that could explain the sex ratio differences we observed in catches from these two areas

Discovery of a Mid-L Dwarf Companion to the L 262-74 System

We present the discovery of CWISE J151044.74$-$524923.5, a wide low-mass companion to the nearby ($\sim$24.7 pc) system L 262-74, which was identified through the Backyard Worlds: Planet 9 citizen science project. We detail the properties of the system, and we assess that this companion is a mid-L dwarf, which will need to be verified spectroscopically. With an angular separation of 74\farcs3, we estimate a projected physical separation of $\sim$1837 au from the central system

Seagrass macroinvertebrate bycatches support mosquito net trawl fishery in Madagascar

The use of mosquito nets, primarily for targeting small and/or juvenile fish, has rapidly increased in Western Indian Ocean shallow seagrass beds and coral reefs over the last 20 years. However, to date, invertebrate by-catch by locally-made fishing gear has not been reported. We studied the mosquito net trawl fishery in seagrass areas in the Bay of Toliara, Southwest Madagascar through the GPS tracking of fishers from August 2018 to February 2019. Catches were monitored through monthly landing surveys to characterize spatial temporal patterns in the abundance and diversity of macroinvertebrates in the seagrass beds. Fishing was carried out at low tide, mostly at night, by fishers pulling a hand-made trawl net of varying dimensions. Overall, 43 macroinvertebrate taxa were identified out of 217,080 individuals collected from 109 catch samples. Catches were generally composed of crustaceans (mainly Portunidae, Processidae, Penaeidae, and Alpheidae). The crab Thalamita mitsiensis largely dominated the abundance and biomass of the macroinvertebrate assemblage (from 6% to 100% and from 5 to 100% of the overall density and biomass, respectively). Macroinvertebrates composed 1.5% to 100% of the total catch per trip (i.e., 4–55 kg trip−1). They were sold for human consumption or animal feed, which provided additional income to fishers (USD 1–24 trip−1 and 1–72% of catch income per trip). This study revealed that macroinvertebrate resources provide valuable by-catch to small-scale fishers in Southwest Madagascar. This bycatch generates income that further encourages the use of mosquito net trawls and exacerbates their negative effects on coastal seagrass ecosystems and fisheries