School of Aerospace

Management of plant parasitic nematodes on sweet potatoes using biochar and chicken manure in Bungoma County, Kenya

2026-06-16T06:27:18Z

Management of plant parasitic nematodes on sweet potatoes using biochar and chicken manure in Bungoma County, Kenya Ngatia, George Sweet potato (Ipomoea batatas L.) is a source of food and nutrition in many developing nations. Plant Parasitic Nematodes (PPN) significantly reduce its productivity and yield. Synthetic nematicides used to manage PPN are harmful to the environment, non- target species and humans, and hence the need for safer and effective PPN management options. Thus, the aim of this study was to examine the effect of soil organic amendments on sweet potatoes and plant parasitic nematodes in Bungoma County, Kenya. The specific objectives were to: Assess the impact of drill and ridge farming systems on sweet potato yield; Evaluate the effect of biochar and chicken manure on sweet potato growth and yield; and Determine the effect of biochar and chicken manure on plant parasitic nematode abundance and diversity. A total of eleven treatments consisting of sole and combined soil amendment treatments of biochar and chicken manure were tested on sweet potatoes planted under drill and ridge farming systems on three farms (Ben, Mabanga and Nafula) using a completely randomized design and randomized complete block design in the first and second planting seasons, respectively. Data on plant biomass and yield that included total tuber weight and number, and marketable and non-marketable tuber weight and number were collected at harvest time, while the initial and final population density of PPN in the soil and on plant roots was collected at planting and harvest time, respectively. Data was analyzed using one-way analysis of variance and significant means separated using Tukey test in the R software. Results from each farm showed no significant yield differences (P=0.05) among treatments tested on sweet potatoes planted under drill farming. However, treatments tested under ridge farming produced significantly higher (P≤0.05) total tuber weight when compared to those under the drill farming, indicating that ridges ensured that the sweet potato roots had enough space to grow and develop. While biochar treatment increased plant biomass, co-application of biochar and chicken manure (five tonnes each) and the sole application of ten tonnes of chicken manure significantly increased (P≤0.05) total and marketable tuber weight, which is attributed to the nutrient-rich water released as a result of the decomposition of chicken manure. Economically significant PPN of sweet potatoes belonging to the genera Pratylenchus, Meloidogyne and Rotylenchulus were more prevalent in the soil than roots. Mabanga farm had significantly higher (P≤0.05) population density of PPN than Ben and Nafula farms. Co-applications of biochar and chicken manure significantly decreased (P≤0.05) the population size of PPN on all farms, but their impact on the different PPN genera was varied. Ridge farming with organic amendments, offers a sustainable strategy for sweet potato production. This study recommends field co-applications of biochar and chicken manure mixture (five tonnes each) under the ridge farming system as practical strategies to boost yield and reduce plant parasitic nematode pressure in sweet potato production.

Intergenerational benefits of microbial priming on performance of finger millet against parasitic- nematodes

2026-06-12T06:51:13Z

Intergenerational benefits of microbial priming on performance of finger millet against parasitic- nematodes Kiptoo, Stanley Finger millet (Eleusine coracana L.) is an important staple grain crop that contributes significantly to food security and income. It’s grown in semi-arid areas. However, the production of finger millet is constrained by conditions of low soil fertility and root- knot nematodes (Meloidogyne javanica). Beneficial soil microbes provide an alternative and potentially sustainable option for farmers, showing promise in enhancing plant growth and resistance, and these benefits can be pass down through generations creating intergenerational effects. The broad objective of this study is to contribute towards increased finger millet yields through intergenerational priming effects of efficacious Bacillus amyloliquefaciens, Purpureocillium lilacinum, and Trichoderma asperellum. Finger millet plants were grown for two generations. In the first generation, finger millet plants were inoculated with the respective microbes, and their growth and yield parameters evaluated. Seeds harvested from these microbe- primed plants were then used to establish a second generation, which was grown without additional microbial inoculation. These second-generation plants were challenged with M. javanica to assess intergenerational acquired resistance and growth potential. The results indicated that seeds from B. amyloliquefaciens inoculated plants showed improved grain weight (p < 0.05) of 83.2% in the second generation. P. lilacinum resulted in grain weight increase by 41% while T. asperellum did not increase grain weight. Plants treated with B. amyloliquefaciens and P. lilacinum in the previous generation resulted in significantly reduced M. javanica infection in their progeny from 407.5 J2 (g soil) −1 to 222.5 J2 (g soil) −1 and 170 J2 (g soil) −1, respectively. This study demonstrates that microbial priming, particularly with B. amyloliquefaciens, not only promotes growth and yield but also induces acquired resistance to root-knot nematodes in finger millet. These findings offer promising insights into the development of sustainable and eco-friendly strategies for enhancing crop resilience and productivity through natural plant-microbe interactions. Microbial seed priming using Bacillus amyloliquefaciens and Purpureocillium lilacinum should be promoted to enhance finger millet growth and nematode resistance. Further multi-location and multi-season studies are needed to confirm field effectiveness and support adoption by farmers.

ASSESSMENT OF RECORDS MANAGEMENT PRACTICES AT RURAL ELECTRIFICATION AUTHORITY, KENYA

2023-11-15T09:19:45Z

ASSESSMENT OF RECORDS MANAGEMENT PRACTICES AT RURAL ELECTRIFICATION AUTHORITY, KENYA Nambwaya, Timothy O. Rural Electrification Authority (REA) is one of the public organizations in Kenya that creates a lot of records in its operations. However, the measures that the Authority has implemented to manage these records have not fully resulted in effective records management. Thus, the aim of the study was to assess the current status of records management at REA with a view to proposing strategies to enhance records management in the Authority. Objectives that guided this study were to: examine records management procedures currently in place at REA; investigate the non-technical records management infrastructure at REA and how it supports the records management function; determine the level of computerization of records at REA and how this has impacted the Authority’s effectiveness in service delivery; and propose strategies to enhance records management within REA. The study was guided by integrated records management theory. The research adopted the convergent parallel mixed-methods research approach and a descriptive case survey targeting 139 staff at REA. Yamane’s sample size formular was adopted, and using proportionate stratified and simple random sampling techniques, 106 staff members comprising five (5) and thirteen (13) top and middle level management respectively, and eighty-eight (88) staff at the operational level were selected. Questionnaires and interviews were used to collect data from the participants. Data from the questionnaires was analysed in SPSS for Windows Version 21.0 using descriptive statistics and presented in tables. Interview data was thematically analysed and presented in narrative descriptions and verbatim quotes. It was established by slightly over half of operational staff that REA did not have a documented records management procedures manual, and others said they were not aware of it. This was supported by the middle and top level management, who noted that REA did not have such a manual. Slightly over half of these staff indicated that they had skills in records storage, with a few being skilled in records’ retrieval, filing, and classification. These staff considered the Authority’s support for records management personnel in REA not to be sufficient due to the inadequacy of financial resources, equipment, capacity building support for the staff, the implementation of a scheme of service for records management personnel, and a poor work environment. The majority of these respondents noted that the Authority did not have a records management policy. These findings were corroborated by the middle and top level management, who noted that this had a negative impact on records management at REA. From the middle and top level managers, it was found that although the Authority had partially incorporated computerization or ICTs into its business processes, records management function had not been computerized. Despite this, the operational level staff identified the positive impact that such computerization had on service delivery and effectiveness at REA. Overall, the operational level staff identified the challenges facing records management at REAas high staff turnover, inadequate funding, cooperation and human capital, the absence of supportive policies and procedures. These staff recommended the following strategies to enhance sound records management at REA: adequate funding of records management activities, employment of adequate and competent records management staff, awareness and sensitization programs for records management, application of ICTs, the development and implementatio of supportive policies and procedures in records management. The study concluded that the state of records management in the Authority at the time of the study was not at its optimal level. Consequently, the study proffered recommendations that it is hoped would improve records management as follows: ensure adequate funding of the records management activities; employ enough and competent records management staff; incorporate ICTs in records management processes; develop and implement supportive policies and practices in records management

Some second order reduced parameter subsystem specific optimum rotatable designs in three, four and five dimensions

2022-05-09T07:04:51Z

Some second order reduced parameter subsystem specific optimum rotatable designs in three, four and five dimensions Kisaa, Jacob Masai