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Norain Jamalluddin Festo J Massawe 《The Journal of Horticultural Science and Biotechnology》2019,94(4):448-459
Drought is a major abiotic stress responsible for severe crop losses worldwide. Development of new crop varieties with increased drought tolerance is one way to increase crop productivity. The aim of this study was to characterise the diversity of nine accessions belonging to Amaranthus tricolor and A. cruentus, in response to drought stress using a dry-down protocol to characterise the transpiration efficiency (TE). Plants were subjected to either a gradual dry down or well-watered conditions. Results showed that TE was significantly higher (P < 0.01) in water-deficient (WD) plants compared to water-sufficient (WS) plants, 2.40 g kg?1–7.13 g kg?1 and 2.19 g kg?1–4.84 g kg?1, respectively. There was no significant difference in the fraction of transpirable soil water (FTSW) threshold decline between the amaranth genotypes. TE was highly correlated with yield under both WS (r = 0.89, P < 0.001) and WD conditions (r = 0.662, P < 0.001), and negatively correlated with root-to-shoot ratio under both WS (r = ?0.488, P < 0.05) and WD conditions (r = ?0.460, P < 0.05). Significant genotypic differences were seen for growth rate and stress susceptibility index (SSI). The result obtained in this investigation underline the need to identify genotypic variation in water use efficiency in amaranth.Abbreviations: FTSW: Fraction of transpirable soil water; NTR: normalised transpiration rate; SSI: Stress susceptibility index; TE: transpiration efficiency; WHC: water holding capacity; WD: water-deficient; WS: water-sufficient. 相似文献
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Laura N Cuypers Wim L Cuypers Amélie Gildemyn-Blomme Laura Abraham Senne Aertbeliën Apia W Massawe 《African Zoology》2017,52(2):119-123
In Africa, indigenous multimammate mice (Mastomys natalensis) only appear to live commensally in houses when invasive black rats (Rattus rattus) are absent, yet little is known about the underlying mechanism. Avoidance through smell may cause the absence of M. natalensis from areas occupied by R. rattus, but this hypothesis has not yet been tested. We conducted a Y-maze choice experiment where 15 M. natalensis were offered a choice between corridors containing conspecific scent, R. rattus scent and a control scent. Residence time in the R. rattus corridor was greater than that in the control corridor but equal to that in the M. natalensis corridor, suggesting that multimammate mice do not actively avoid the scent of their invasive competitor. 相似文献
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Bambara groundnut an indigenous crop of African origin is drought tolerant and the third most important leguminous crop in Ghana and Sub-Saharan Africa. In order to assess the level of genetic diversity within a small collection of Ghanaian landraces, molecular analysis was performed using microsatellite markers alongside characterization of morphological features. Genetic distance based on Jaccard’s similarity coefficient from the SSR marker analysis ranged from 0.48 to 0.9 among the landraces. 80 individual genotypes were clustered into 17 units with substantial levels of inter- and intra-landrace polymorphism. The analyses of variance from the morphological characterization for all quantitative traits were statistically significant (p < 0.05) except for terminal leaflet width. The first 4 principal components accounted for 41.97, 20.15, 13.39 and 9.81 % respectively of the morphological variations among the landraces. Qualitative traits however accounted for less of these variations. The results of the present study support the availability of high level of polymorphism within the collection of bambara groundnut analysed. This report is useful to crop improvement and germplasm conservation of bambara groundnut in Ghana. 相似文献
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The effect of drought on the growth and development of bambara groundnut (Vigna subterranea (L.) Verdc.) was studied in controlled-environment glasshouses in the UK. There were three landraces (S19-3, DipC and UN from Namibia, Botswana and Swaziland, respectively) and two watering regimes; a control that was irrigated weekly to 90% field capacity and a drought treatment with no irrigation from 49 days after sowing (DAS) until final harvest (147 DAS). Bambara groundnut responded to drought by reducing the rate of leaf area expansion, final canopy size and total dry matter (TDM) during vegetative growth. Drought also caused significant reductions in pod dry matter (PDM), pod number, seed weight and harvest index (HI), leading to a decrease in final pod yield that was different between landraces. Across landraces, drought reduced mean pod yield from 298 g m−2 to 165 g m−2, representing 45% yield loss. Despite the reduction in all landraces, the mean pod yield across the droughted treatments that had received no water for almost 100 days indicated the resilience of the species to drought. The three landraces differed in their phenology; S19-3 exhibited a reduced phenology while UN maintained the longest life cycle. The different responses of the landraces reflect their adaptation to their local climates where mean annual rainfall ranges between 365 mm (Namibia) and 1390 mm (Swaziland). We discuss the significance of these results for future breeding programmes on bambara groundnut. 相似文献
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Agricultural nematology in East and Southern Africa: problems,management strategies and stakeholder linkages 
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下载免费PDF全文 Herbert Talwana Zibusiso Sibanda Waceke Wanjohi Wangai Kimenju Nessie Luambano‐Nyoni Cornel Massawe Rosa H Manzanilla‐López Keith G Davies David J Hunt Richard A Sikora Danny L Coyne Simon R Gowen Brian R Kerry 《Pest management science》2016,72(2):226-245
By 2050, Africa's population is projected to exceed 2 billion. Africa will have to increase food production more than 50% in the coming 50 years to meet the nutritional requirements of its growing population. Nowhere is the need to increase agricultural productivity more pertinent than in much of Sub‐Saharan Africa, where it is currently static or declining. Optimal pest management will be essential, because intensification of any system creates heightened selection pressures for pests. Plant‐parasitic nematodes and their damage potential are intertwined with intensified systems and can be an indicator of unsustainable practices. As soil pests, nematodes are commonly overlooked or misdiagnosed, particularly where appropriate expertise and knowledge transfer systems are meager or inadequately funded. Nematode damage to roots results in less efficient root systems that are less able to access nutrients and water, which can produce symptoms typical of water or nutrient deficiency, leading to misdiagnosis of the underlying cause. Damage in subsistence agriculture is exacerbated by growing crops on degraded soils and in areas of low water retention where strong root growth is vital. This review focuses on the current knowledge of economically important nematode pests affecting key crops, nematode control methods and the research and development needs for sustainable management, stakeholder involvement and capacity building in the context of crop security in East and Southern Africa, especially Kenya, Tanzania, Uganda and Zimbabwe. © 2015 Society of Chemical Industry 相似文献
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Apia W. Massawe Rhodes H. Makundi Zhibin Zhang Ginethon Mhamphi Ming Liu Hong-Jun Li Steven R. Belmain 《Journal of pest science》2018,91(1):157-168
Rodent pest management traditionally relies on some form of lethal control. Developing effective fertility control for pest rodent species could be a major breakthrough particularly in the context of managing rodent population outbreaks. This laboratory-based study is the first to report on the effects of using fertility compounds on an outbreaking rodent pest species found throughout sub-Saharan Africa. Mastomys natalensis were fed bait containing the synthetic steroid hormones quinestrol and levonorgestrel, both singly and in combination, at three concentrations (10, 50, 100 ppm) for 7 days. Consumption of the bait and animal body mass was mostly the same between treatments when analysed by sex, day and treatment. However, a repeated measures ANOVA indicated that quinestrol and quinestrol + levonorgestrel treatments reduced consumption by up to 45%, particularly at the higher concentrations of 50 and 100 ppm. Although there was no clear concentration effect on animal body mass, quinestrol and quinestrol + levonorgestrel lowered body mass by up to 20% compared to the untreated and levonorgestrel treatments. Quinestrol and quinestrol + levonorgestrel reduced the weight of male rat testes, epididymis and seminal vesicles by 60–80%, and sperm concentration and motility were reduced by more than 95%. No weight changes were observed to uterine and ovarian tissue; however, high uterine oedema was observed among all female rats consuming treated bait at 8 and 40 days from trial start. Trials with mate pairing showed there were significant differences in the pregnancy rate with all treatments when compared to the untreated control group of rodents. 相似文献