Ecological weed management in Sub-Saharan Africa: Prospects and implications on other agroecosystem services

Time requirements, weed control efficacy, and yield effects of three labor-saving weed technologies were tested against hand weeding during three seasons in 2012 and 2013. The technologies included two hand-operated mechanical weeders, the straight-spike and the twisted-spike floating weeder, and the PRE application of oxadiazon. The straight-spike floating weeder reduced weeding time by 32 to 49%, the twisted-spike floating weeder reduced weeding time by 32 to 56%, and the application of herbicide required 88 to 97% less time than hand weeding. Herbicide application provided the best weed control in two of the three seasons. No differences in weed control efficacy were observed between mechanical and hand weeding. Yield differences were only observed in season 3 with higher rice yields after PRE application of oxadiazon compared with other weed management treatments.

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Weed management in upland rice in sub-Saharan Africa: impact on labor and crop productivity

Food Security ◽

10.1007/s12571-014-0351-7 ◽

2014 ◽

Vol 6 (3) ◽

pp. 327-337 ◽

Cited By ~ 12

Author(s):

Philomena Ogwuike ◽

Jonne Rodenburg ◽

Aliou Diagne ◽

Afiavi R. Agboh-Noameshie ◽

Eyram Amovin-Assagba

Keyword(s):

Weed Management ◽

Upland Rice ◽

Crop Productivity ◽

Sub Saharan Africa ◽

Sub Saharan

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Row spacing and weed management methods influences growth and yield of soybean (Glycine max (L.) Merr.)

Agricultura tropica et subtropica ◽

10.2478/ats-2019-0007 ◽

2019 ◽

Vol 52 (2) ◽

pp. 59-71 ◽

Cited By ~ 1

Author(s):

Olumide Samuel Daramola ◽

Olusegun Raphael Adeyemi ◽

Joseph Aremu Adigun ◽

Christopher Olu Adejuyigbe

Keyword(s):

Grain Yield ◽

Weed Control ◽

Weed Management ◽

Dry Matter ◽

Field Trials ◽

Sub Saharan Africa ◽

Growth And Yield ◽

Row Spacing ◽

Subsequent Increase ◽

Sub Saharan

Abstract Weed infestation is among the primary reasons for low yields of soybean in Nigeria and other parts of Sub Saharan Africa (SSA). Field trials were therefore carried out in 2016 and 2017 cropping seasons to evaluate the effect of row spacing and weed management methods on growth and yield of soybean. The use of 50 cm row spacing resulted in significant (P < 0.05) reduction in weed cover score, weed density and weed dry matter with subsequent increase in soybean growth and grain yield compared to 75 and 100 cm row spacings in both years. In addition, early weed control with probaben at 2.0 kg a.i (active ingredient) ha1 followed by (fb) supplementary hoe weeding (shw) at 6 weeks after sowing (WAS) suppressed weeds and increased soybean growth, which carried through to final dry matter and yield. Pre-emergence application of Probaben fb shw at 6 WAS gave the best weed control and resulted in significantly (P < 0.05) higher soybean grain yield compared to two and three hoe weedings or sole application of probaben under 50 and 75 cm inter-row spacing. However, three hoe weedings gave the best weed control and grain yield under 100 cm inter-row spacing. These results suggest that narrow row spacing of 50 cm and weed control by pre-emergence application of probaben fb shw will improve the productivity of soybean. Wide row spacing, however, required longer weed-free period and consequently multiple hoe weeding for optimum soybean yield.

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FARMERS’ PERCEPTIONS ON MECHANICAL WEEDERS FOR RICE PRODUCTION IN SUB-SAHARAN AFRICA

Experimental Agriculture ◽

10.1017/s001447971700059x ◽

2018 ◽

Vol 55 (1) ◽

pp. 117-131 ◽

Cited By ~ 1

Author(s):

JEAN-MARTIAL JOHNSON ◽

JONNE RODENBURG ◽

ATSUKO TANAKA ◽

KALIMUTHU SENTHILKUMAR ◽

KOKOU AHOUANTON ◽

...

Keyword(s):

Weed Management ◽

Management Practices ◽

Water Status ◽

Sub Saharan Africa ◽

Field Size ◽

Follow Up Study ◽

Wide Range ◽

Sub Saharan ◽

Hand Weeding

SUMMARYCompetition from weeds is one of the major biophysical constraints to rice (Oryza spp.) production in sub-Saharan Africa. Smallholder rice farmers require efficient, affordable and labour-saving weed management technologies. Mechanical weeders have shown to fit this profile. Several mechanical weeder types exist but little is known about locally specific differences in performance and farmer preference between these types. Three to six different weeder types were evaluated at 10 different sites across seven countries – i.e., Benin, Burkina Faso, Côte d'Ivoire, Ghana, Nigeria, Rwanda and Togo. A total of 310 farmers (173 male, 137 female) tested the weeders, scored them for their preference, and compared them with their own weed management practices. In a follow-up study, 186 farmers from Benin and Nigeria received the ring hoe, which was the most preferred in these two countries, to use it during the entire crop growing season. Farmers were surveyed on their experiences. The probability of the ring hoe having the highest score among the tested weeders was 71%. The probability of farmers’ preference of the ring hoe over their usual practices – i.e., herbicide, traditional hoe and hand weeding – was 52, 95 and 91%, respectively. The preference of this weeder was not related to gender, years of experience with rice cultivation, rice field size, weed infestation level, water status or soil texture. In the follow-up study, 80% of farmers who used the ring hoe indicated that weeding time was reduced by at least 31%. Of the farmers testing the ring hoe in the follow-up study, 35% used it also for other crops such as vegetables, maize, sorghum, cassava and millet. These results suggest that the ring hoe offers a gender-neutral solution for reducing labour for weeding in rice as well as other crops and that it is compatible with a wide range of environments. The implications of our findings and challenges for out-scaling of mechanical weeders are discussed.

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RTS,S/AS01, a vaccine targeting pre-erythrocytic stages of Plasmodium falciparum

Emerging Topics in Life Sciences ◽

10.1042/etls20170101 ◽

2017 ◽

Vol 1 (6) ◽

pp. 533-537

Author(s):

Lorenz von Seidlein ◽

Borimas Hanboonkunupakarn ◽

Podjanee Jittmala ◽

Sasithon Pukrittayakamee

Keyword(s):

Protective Efficacy ◽

Age Groups ◽

Sub Saharan Africa ◽

Phase Iii ◽

European Medicines Agency ◽

Older Children ◽

Pivotal Phase ◽

Malaria Epidemiology ◽

Maximum Benefit ◽

Sub Saharan

RTS,S/AS01 is the most advanced vaccine to prevent malaria. It is safe and moderately effective. A large pivotal phase III trial in over 15 000 young children in sub-Saharan Africa completed in 2014 showed that the vaccine could protect around one-third of children (aged 5–17 months) and one-fourth of infants (aged 6–12 weeks) from uncomplicated falciparum malaria. The European Medicines Agency approved licensing and programmatic roll-out of the RTSS vaccine in malaria endemic countries in sub-Saharan Africa. WHO is planning further studies in a large Malaria Vaccine Implementation Programme, in more than 400 000 young African children. With the changing malaria epidemiology in Africa resulting in older children at risk, alternative modes of employment are under evaluation, for example the use of RTS,S/AS01 in older children as part of seasonal malaria prophylaxis. Another strategy is combining mass drug administrations with mass vaccine campaigns for all age groups in regional malaria elimination campaigns. A phase II trial is ongoing to evaluate the safety and immunogenicity of the RTSS in combination with antimalarial drugs in Thailand. Such novel approaches aim to extract the maximum benefit from the well-documented, short-lasting protective efficacy of RTS,S/AS01.

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Mortality and Society in Sub-Saharan Africa

Population Studies ◽

10.1080/0032472031000147416 ◽

1993 ◽

Vol 47 (3) ◽

pp. 555-556

Author(s):

Lado Ruzicka

Keyword(s):

Sub Saharan Africa ◽

Sub Saharan

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Sub-Saharan Africa

The Military Balance ◽

10.1080/04597228708459635 ◽

1987 ◽

Vol 87 (1) ◽

pp. 118-142

Keyword(s):

Sub Saharan Africa ◽

Sub Saharan

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Adolescent Suicidality as Seen in Rural Northeastern Uganda

Crisis ◽

10.1027/0227-5910/a000059 ◽

2011 ◽

Vol 32 (1) ◽

pp. 43-51 ◽

Cited By ~ 17

Author(s):

Eugene Kinyanda ◽

Ruth Kizza ◽

Jonathan Levin ◽

Sheila Ndyanabangi ◽

Catherine Abbo

Keyword(s):

Low Socioeconomic Status ◽

Sub Saharan Africa ◽

Psychosocial Risk ◽

Psychiatric Nurses ◽

Health Concern ◽

Cross Sectional ◽

Childhood Experiences ◽

Low Socioeconomic ◽

Dsm Iv ◽

Sub Saharan

Background: Suicidal behavior in adolescence is a public health concern and has serious consequences for adolescents and their families. There is, however, a paucity of data on this subject from sub-Saharan Africa, hence the need for this study. Aims: A cross-sectional multistage survey to investigate adolescent suicidality among other things was undertaken in rural northeastern Uganda. Methods: A structured protocol administered by trained psychiatric nurses collected information on sociodemographics, mental disorders (DSM-IV criteria), and psychological and psychosocial risk factors for children aged 3–19 years (N = 1492). For the purposes of this paper, an analysis of a subsample of adolescents (aged 10–19 years; n = 897) was undertaken. Results: Lifetime suicidality in this study was 6.1% (95% CI, 4.6%–7.9%). Conclusions: Factors significantly associated with suicidality included mental disorder, the ecological factor district of residence, factors suggestive of low socioeconomic status, and disadvantaged childhood experiences.

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