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Journal and Journal Articles: Recent submissions
Now showing items 481-500 of 5266
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Effect of adult feeding substrates on survival and reproduction of Therophilus javanus and Phanerotoma syleptae, two parasitoids of Maruca vitrata
(2022)The current study was designed to assess the effect of different feeding substrates on survival and reproduction of Therophilus javanus (Bhat & Gupta) (Hymenoptera: Braconidae) and Phanerotoma syleptae Zettel (Hymenoptera: Braconidae) in order to optimize their potential as biological control agents against Maruca vitrata Fabricius (Lepidoptera: Crambidae). Experiments were carried out in laboratory with batches of ten adult females exposed to flowers of either Vigna unguiculata (L) Walp., Tephrosia ... -
Assessing lethal doses of the baculovirus MaviMNPV and the effect of its combination with neem oil on the survival of Maruca vitrata (Fabricius) (Lepidoptera: Crambidae) larval stages in laboratory
(2022)Cowpea production is limited by predation from several insect pests, including Maruca vitrata (F.) (Lepidoptera: Crambidae) as one of the most destructive. The present study aimed to assess the pesticidal effect of neem oil and the baculovirus MaviMNPV (separately and in combination) on M. vitrata under laboratory conditions. Eight treatments in a 4-replicate randomized block design (including control) were assessed at each of the five M. vitrata larval stages. Neem oil induced larval mortality ... -
Banana mapping in heterogenous smallholder farming systems using high-resolution remote sensing imagery and machine learning models with implications for banana bunchy top disease surveillance
(2022)Banana (and plantain, Musa spp.), in sub-Saharan Africa (SSA), is predominantly grown as a mixed crop by smallholder farmers in backyards and small farmlands, typically ranging from 0.2 ha to 3 ha. The crop is affected by several pests and diseases, including the invasive banana bunchy top virus (BBTV, genus Babuvirus), which is emerging as a major threat to banana production in SSA. The BBTV outbreak in West Africa was first recorded in the Benin Republic in 2010 and has spread to the adjoining ... -
Receptor-like Kinases (LRR-RLKs) in response of plants to biotic and abiotic stresses
(2022)Plants live under different biotic and abiotic stress conditions, and, to cope with the adversity and severity, plants have well-developed resistance mechanisms. The mechanism starts with perception of the stimuli followed by molecular, biochemical, and physiological adaptive measures. The family of LRR-RLKs (leucine-rich repeat receptor-like kinases) is one such group that perceives biotic and abiotic stimuli and also plays important roles in different biological processes of development. This ... -
A novel self-cleaving viroid-like RNA identified in RNA preparations from a citrus tree is not directly associated with the plant
(2022)Viroid and viroid-like satellite RNAs are infectious, circular, non-protein coding RNAs reported in plants only so far. Some viroids (family Avsunviroidae) and viroid-like satellite RNAs share self-cleaving activity mediated by hammerhead ribozymes (HHRzs) endowed in both RNA polarity strands. Using a homology-independent method based on the search for conserved structural motifs of HHRzs in reads and contigs from high-throughput sequenced RNAseq libraries, we identified a novel small (550 nt) ... -
Tephritid fruit fly species composition, seasonality, and fruit infestations in two central African agro-ecological zones
(2022-11-13)Bactrocera dorsalis and several Africa-native Ceratitis species are serious constraints to fruit production in sub-Saharan Africa. A long-term trapping and fruit collection study was conducted (2011–2016) in two contrasting agro-ecological zones (AEZs) of Cameroon to determine fruit fly species composition, seasonality, attraction to various lures and baits, and fruit infestation levels. Ten tephritid species from genera Bactrocera, Ceratitis, Dacus, and Perilampsis were captured in traps. Bactrocera ... -
Evaluating the heterogeneous impacts of adoption of climate-smart agricultural technologies on rural households' welfare in Mali
(2022-11-04)Climate change is negatively affecting agricultural production in the Sahel region. Climate-Smart Agricultural Technologies (CSATs) are disseminated to reduce these negative effects, and particularly those on resource-poor farm households. This article investigates the distributional impacts of the adoption of CSAT on-farm households’ welfare using a dataset that covers four regions, 32 communes, 320 villages, and 2240 households in Mali. Using an instrumental variable quantile treatment effects ... -
Farmers' credit access in the Democratic Republic of Congo: empirical evidence from youth tomato farmers in Ruzizi plain in south Kivu
(2022)This article assesses the opinions of youth tomato growers on the accessibility of agricultural credit and factors that influence the accessibility in the Democratic Republic of the Congo (DRC). Data originated from a household survey for the 2019/2020 farming season. We interviewed 218 youth tomato growers from 6 horticulture production zones in the South-Kivu, eastern DRC. The result reveals a low rate of 20.6% on accessing agricultural credit among tomato growers. The topmost nature of agricultural ... -
Comparative analysis of variation in African Bambara groundnut [Vigna subterranea (L) Verdc.] landraces assessed through seed traits
(2022-11)Bambara groundnut [Vigna subterranea (L.) Verdc.] originated from the African continent and plays social-economic roles in regions where it is consumed. This study examined 297 landraces of African Bambara groundnut from four African regions (West, Central, East, and Southern) to estimate the extent of diversity in each population, identify useful seed traits for differentiation in the population and estimate association among seed quantitative traits using eight qualitative and seven quantitative ... -
Cassava-maize intercropping systems in southern Nigeria: radiation use efficiency, soil moisture dynamics, and yields of component crops
(2022-07)Efficient utilization of incident solar radiation and rainwater conservation in rain-fed smallholder cropping systems require the development and adoption of cropping systems with high resource use efficiency. Due to the popularity of cassava-maize intercropping and the food security and economic importance of both crops in Nigeria, we investigated options to improve interception of photosynthetically active radiation (IPAR), radiation use efficiency (RUE), soil moisture retention, and yields of ... -
Understanding changes in cassava root dry matter yield by different planting dates, crop ages at harvest, fertilizer application and varieties
(2022-12-23)Cassava is a perennial crop that can adapt to periods of drought at different times in a growing season, which permits scheduling planting and harvest to develop production systems supplying roots continuously. However, farmers plant and harvest cassava at the onset of rains which creates glut and results in unattractive root prices. Thus, farmers need to understand how cassava varieties respond to different planting dates and crop ages at harvest to be able to use opportunities in income generation ... -
Effects of expanding cassava planting and harvesting windows on root yield, starch content and revenue in southwestern Nigeria
(2022-10-01)Cassava (Manihot esculenta Crantz) is an important staple crop in Nigeria. It provides approximately 80 % of the caloric intake in Nigeria. High starch content and fresh root yields are important for the commercialization of cassava. Cassava is a perennial crop, and it can be produced all year round. However, cassava fresh root yield and starch content are strongly influenced by environmental conditions such as rainfall. Therefore, it is important to identify planting and harvest periods to attain ... -
Simulating potential yield of rainfed soybean in northeast Nigeria
(2023-01)We used the CROPGRO-Soybean model to simulate the production potential of rainfed soybean in northeast Nigeria. Data from ten soybean experiments conducted under optimal conditions in 2016–2018 at Kano and Dambatta in the Sudan savanna (SS) agroecological zone were used to determine the cultivar coefficients and calibrate the model for the varieties TGX 1448–2E and TGX1951–3 F. The model was evaluated with data from four phosphorous response trials conducted at Zaria and Doguwa in the northern ... -
Leveraging digital tools and crowdsourcing approaches to generate high-frequency data for diet quality monitoring at population scale in Rwanda
(2022-01-07)Diet quality is a critical determinant of human health and increasingly serves as a key indicator for food system sustainability. However, data on diets are limited, scattered, often project-dependent, and current data collection systems do not support high-frequency or consistent data flows. We piloted in Rwanda a data collection system, powered by the principles of citizen science, to acquire high frequency data on diets. The system was deployed through an unstructured supplementary service data ... -
A framework to understand the social impacts of agricultural trade
(2022-08-30)While international trade in agricultural commodities can spur economic development especially where governance is strong, there are also concerns about the local impacts of commodity production and their distribution. Previous frameworks have primarily focused on trade effects on environmental conditions in production regions, as well as economic growth and food security. Instead, we develop a conceptual framework for understanding the impact of agricultural trade on multidimensional wellbeing ... -
Access to finance and rural youth entrepreneurship in Benin: Is there a gender gap?
(2022-01-27)Rural entrepreneurship is an important employment generation intervention for the fast-growing young labour force in developing countries. Many bottlenecks including access to finance impede rural youths from performing in their new ventures. This paper examines the impact of access to finance on rural youths' entrepreneurship in Benin using data from the second wave of the School-To-Work Transition Survey, involving over 900 youths. The paper employs the endogenous switching regression technique, ... -
Contributions of integrated soil fertility management (ISFM) to various sustainable intensification impact domains in Tanzania
(2022-12)CONTEXT The implementation of integrated soil fertility management (ISFM) varies widely among farmers, from no ISFM to multiple computations of ISFM components (i.e., improved germplasm, organic resources, fertilizers, and local adaptations e.g., soil and water conservation (SWC)). There is no comprehensive report on farmers' use of ISFM components and their impact on sustainable intensification domains of productivity, economic, social, human condition, and environment and the associated variations ... -
Variability of flowering sex and its effect on agronomic trait expression in white guinea yam
(2022-04-25)White Guinea yam (Dioscorea rotundata) is mainly a dioecious tuberous crop that produces flowers of varying sex phenotypes. Agronomic traits in Guinea yam differ according to the sex phenotype, but the precise interaction between the traits and sex phenotype is not clearly understood. This might be due to the high heterozygosity of yam where cultivars with different flowering sex have different genetic backgrounds, which mask the sole effect of sex phenotype on the agronomic traits. This study ...
