Agronomic and quantitative trait loci analyses of yield and yield-related traits in pigeonpea.

Doctor of Philosophy in Plant Breeding. University of KwaZulu-Natal, Pietermaritzburg, 2017.Abstract available in PDF file

Acaricidal activities of extracts of Commiphora swynnertonii Burtt (Burseraceae), Melia volkensii Gürke, Turraea abyssinica Hochst., Turraea floribunda Hochst and Turraea cornucopia Styles & F. White (Meliaceae) against the brown ear tick Rhipicephalus ap

Acaricidal activities of extracts of Commiphora swynnertonii Burtt  (Burseraceae), Melia volkensii Gürke, Turraea abyssinica Hochst., Turraea floribunda Hochst and Turraea cornucopia Styles & F. White (Meliaceae) against the brown ear tick Rhipicephalus appendiculatus Neumann Extracts of the stem bark of Commiphora swynnertonii, the root bark ofTurraea abyssinica, T. cornucopia, T. floribunda and the ripened fruits of Melia volkensii were tested for acaricidal activities against nymphal and adult stages of Rhipicephalus appendiculatus in the laboratory. At a concentration of 10% (w/v), hexane and ethyl acetate extracts of C. swynertonii induced mean mortalities of 71% and 54% respectively, in two week old nymphs. A 10% (w/v) hexane extract was found to be as effective as the commercial acaricide Triatix against the twoweek- old nymphs. Extracts of T. cornucopia, T. abyssinica and M. volkensii induced no mortality in nymphs and adults, but suppressed oviposition capacity during the first day. On the other hand, 500µl of 10% (w/v) methanol extracts of T. cornucopia and T. floribunda delayed attachment by adult females of R. appendiculatus on the rabbit ears, engorgement and hatchability of their eggs.Keywords: acaricidal, activity, plant extracts, Burseraceae, Meliaceae,Rhipicephalus appendicullatus

Antifeedant activity of twenty six plant extracts and pure compounds from the root bark of Toddalia asiatica (L) (Rutaceae) against the anomalous emperor moth Nudaurelia belina (Saturnidae)

The antifeedant activity of petroleum ether (PE) (40-60%) extract of the root bark of T. asiatica and twenty five other plant extracts was investigated against the anomalous emperor moth N. belina. The petroleum ether extract of stem bark of Albizia anthelmintica, leaves of Cassia occidentalis, Balanites aegyptica, seeds of Cucumis sativaus, root bark of T. asiatica, root bark of Celtis durandii, B. aegyptica and whole plant of Cisus quadrangularis were found to be active against N. belina at a concentration of 1% w/v in a modified leaf disc method. Also, methanol extracts of the root bark of A. muricata and Eucalyptus spp were found to be active against N. belina at a concentration of 1% w/v. Three cumarius; dihydrotoddanol, toddanol and toddalactone and the alkaloid dihydrochelerynthrine isolated from the PE extract of the root bark of T. asiatica exhibited antifeedant activity at as low as 0.05% w/v. Toddaculine and toddanone which were also isolated from the P.E. extract had no activity at 0.05% w/v.Keywords: Antifeedants, Toddalia asiatica, Rutaceae, Nudaurelia belina, Saturnida

Genomics-assisted breeding for boosting crop improvement in pigeonpea (Cajanus cajan)

Pigeonpea is an important pulse crop grown predominantly in the tropical and sub-tropical regions of the world. Although pigeonpea growing area has considerably increased, yield has remained stagnant for the last six decades mainly due to the exposure of the crop to various biotic and abiotic constraints. In addition, low level of genetic variability and limited genomic resources have been serious impediments to pigeonpea crop improvement through modern breeding approaches. In recent years, however, due to the availability of next generation sequencing and high-throughput genotyping technologies, the scenario has changed tremendously. The reduced sequencing costs resulting in the decoding of the pigeonpea genome has led to the development of various genomic resources including molecular markers, transcript sequences and comprehensive genetic maps. Mapping of some important traits including resistance to Fusarium wilt and sterility mosaic disease, fertility restoration, determinacy with other agronomically important traits have paved the way for applying genomics-assisted breeding (GAB) through marker assisted selection as well as genomic selection (GS). This would accelerate the development and improvement of both varieties and hybrids in pigeonpea. Particularly for hybrid breeding programme, mitochondrial genomes of cytoplasmic male sterile (CMS) lines, maintainers and hybrids have been sequenced to identify genes responsible for cytoplasmic male sterility. Furthermore, several diagnostic molecular markers have been developed to assess the purity of commercial hybrids. In summary, pigeonpea has become a genomic resources-rich crop and efforts have already been initiated to integrate these resources in pigeonpea breeding

Aflatoxin contamination in Tanzania: quantifying the problem in maize and groundnuts from rural households

Published online: 28 Apr 2021Aflatoxins are toxic and carcinogenic secondary metabolites, produced by Aspergillus flavus and Aspergillus parasiticus, which contaminate food and feed and threaten human and animal health. To assess the prevalence of aflatoxins in Tanzania, 180 groundnut and 200 maize samples were collected from 9 and 10 districts, respectively. Aflatoxin contamination was quantified using high performance liquid chromatography. Aflatoxins were detected in samples collected from all districts and prevalence ranged from 92 to 100% for groundnuts and 10 to 80% for maize. The mean aflatoxin level for groundnuts was 6.37 μg/kg and the highly contaminated sample had 40.31 μg/kg. For maize, the mean aflatoxin level was 12.47 μg/kg and the highly contaminated sample had 162.40 μg/kg. The estimated average probable daily intake (APDI) of aflatoxin B1 (AFB1) from groundnuts consumption was 1.88 ng/kg body weight/day, while for maize, it ranged between 151.98-272.89 ng/kg body weight/day. The APDI for both groundnut and maize exceeded the provisional maximum tolerable daily intake (PMTDI) of AFB1 for adults (1 ng/kg body weight/day), bringing about health concerns for populations in Tanzania. Another alarming finding was that 75% of the farmers who provided samples for analysis were not aware of aflatoxins or the negative health impacts from consuming contaminated products. Results reported in this paper show that aflatoxin contaminated staple crops are widely distributed in Tanzania and that the risk of human exposure is high due to diet preferences. Awareness campaigns are required to inform and protect farmers and consumers

Plague: past, present and future

[Introduction] Recent experience with SARS (severe acute respiratory syndrome) [1] and avian flu shows that the public and political response to threats from new anthropozoonoses can be near-hysteria. This can readily make us forget more classical animal-borne diseases, such as plague (Box 1). Three recent international meetings on plague (Box 2) concluded that: (1) it should be re-emphasised that the plague bacillus (Yersinia pestis) still causes several thousand human cases per year [2,3] (Figure 1); (2) locally perceived risks far outstrip the objective risk based purely on the number of cases [2]; (3) climate change might increase the risk of plague outbreaks where plague is currently endemic and new plague areas might arise [2,4]; (4) remarkably little is known about the dynamics of plague in its natural reservoirs and hence about changing risks for humans [5]; and, therefore, (5) plague should be taken much more seriously by the international community than appears to be the case

Education Stakeholders’ Attitudes on the Implementation of Inclusive education in Tanzania: Case study of Tanga City Council

This study aimed to investigate the attitude of education stakeholders on the implementation of inclusive education in Tanzania, specifically in Tanga City Council. The study was guided by three research questions which enabled the researcher to formulate the research tools. The questions were; How do education stakeholders perceive the implementation of inclusive education? What is the status of the learning environment which support the implementation of inclusive education? What challenges do teachers face in the implementation of inclusive education? Qualitative–method research approach was employed to obtain data from the sample of 52 study participants who included 20 Primary School Pupils, 10 Primary School Teachers, 5 Headteachers, 5 Ward Education Coordinators, 10 Parents, 1 District Social Worker Officer, 1 District Education Officer and 1 Regional Education Officer. Questionnaires, interviews, and observation were used to collect data. The study findings revealed that stakeholders studied have positive attitude towards implementation of inclusive education. The study indicated that inclusive education plays a great role in developing confidence among all children learning in the inclusive setting regardless of their varried needs. The study revealed that, inclusive education enhance social relationship among children with varied educational needs, inclusive education is faced with lack of special in-service training for teachers, inadequate learning and teaching facilities, the negative perception among some community members including parents and overcrowded classrooms which affect its implementation. The study recommends that ministries responsible for education should ensure that primary school teachers are aware of the concept of inclusive education for its effective implementation

Household livelihood strategies in the miombo woodlands of Tanzania: emerging trends

The study was undertaken in Tanzania to assess the effect of some macro-economic policies on livelihood strategies for households within or in close proximity in miombo woodlands. The focus was on how their responses are impacting on the management and use of the woodlands. Data were collected at macro level from three sites categories as remote, intermediate and peri-urban. Also data on important macroeconomic trends were collected. The results indicate that reductions government spending have decreased agricultural support in terms of extension services and subsidies on farm inputs. The increase in prices of input factors relative to output has raised costs of farm inputs, cost of living in general and decreased disposable incomes for most rural dwellers, forcing some of them into extensive forest product exploitation and trade for each incomes. in the study sites, some forest products contribute between 50-70% of annual household incomes. However not many households have the capacity to take the advantage of promising forest-based income generating activities. Economic hardships also led to changes in gender roles particularly in per-urban and intermediate sites. Women are increasingly expanding their roles, away from traditional domestic activities to income generating activities such as forest product exploitation and sale, casual labour and petty business. Men are gradually talking up activities which have traditionally been in the domain of women. The role of local institutions and traditional values in management of woodlands has declined. Village governments have replaced village and clan elders in land allocation. Local beliefs of value for forest protection and traditional property rights which influence utilization of communal resources have gradually been eroded. Some macro-economic policies have created conditions for broadening the cash income base of rural communities and have put value on some otherwise non-tradable forest products. Local communicates advocate for the full involvement in the management and use of these resources.

Forest policies in Malawi, Mozambique, Tanzania and Zimbabwe

Many countries in eastern and southern Africa have lost significant natural forest resources. Initially the pace was gradual, but it has accelerated very much in the recent past. Some of the efforts made to contain the situation include revising past policies to improve forestry development and conservation. This paper traces the evolution of such policies together with corresponding implementation mechanisms in Malawi, Mozambique, Tanzania and Zimbabwe. Although broad policy statements on involving local communities in forestry have existed in some countries for several decades, adequate resources have not been committed for their effective operationalisation. Generally, the forestry sector in southern Africa has lagged behind other sectors in revising its policies to adequately reflect political and socio-economic changes. Political and socio-economic policies appear to have taken precedence over forest sector policies, with far reaching consequences for the sector. However, current forest policies are more comprehensive in terms of stakeholders considered and issues addressed