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Item Relationships between agronomic practices, soil chemical characteristics and striga reproduction in dryland areas of Tanzania(David publishing, 2012-10-20) Abdul, Kudra; Chemining’wa, George N.; Onwonga, Richard N.The parasitic weed Striga poses a serious threat to cereal production in sub-Saharan Africa. For many years, technological packages for the control of this weed were proposed and implemented on farmers’ fields. A survey was carried out in farmers’ fields in 2010/2011 cropping season in selected dryland areas of Tanzania to: (a) determine the Striga plant counts, number of capsules/Striga plant and agronomic practices used by farmers to control Striga; and (b) evaluate the relationship between Striga reproduction, soil chemical characteristics and agronomic practices. Soil samples at 0-20 cm depth were collected from 20 different farmers’ fields. The soil samples were analyzed for pH, organic carbon, N, P and K. Results showed that there was low adoption of recommended Striga control methods. Regression analysis of agronomic practices and soil chemical characteristics revealed a positive improvement of soil N and organic carbon and reduction of soil P and K content as one shifted from sole planting to intercropping. The results showed that potassium was highly positively related to number of capsules/Striga plant. There was a reduction in the number of capsules/plant as one moved from sole planting to intercropping. Based on these findings, K in the Striga infested in soils positively influenced Striga reproduction and seed bank replenishment, hence high soil K levels may lead to high Striga incidence.Item Striga asiatica growth and seed production in response to organic and inorganic P - fertilizers(Access International Journals, 2014-03) Kudra, A; Chemining’wa, G. N; Sibuga, K. PThe measures for Striga management are hindered by a unique survival strategy of the weed, whereby it produces large amount of seeds. Therefore, prevention of further build up of the Striga seed bank through control measures remains an essential component in Striga control. The influence of fertilizers on Striga seed production was studied for two consecutive years (2009/2010 and 2010/2011) at Hombolo Research Station-Dodoma, Tanzania. Farmyard manure (5.9 tons/ha equivalent to 50 kg N/ha), chicken manure (2.5 tons/ha equivalent to 50 kg N/ha), urea (50 kg N/ha) and triple superphosphate (TSP) (40 kg P/ha) were tested on sorghum variety Macia in a randomized complete block design replicated four times. Striga plants supplied with chicken manure, urea and TSP had significantly fewer Striga capsules per plant than farmyard manure treated and control (without fertilizer application) plants. However, the mechanism by which phosphorus application reduced Striga reproduction in the current study is yet unclear. Based on this study, fertilizers have the potential to reduce Striga reproduction. Even though fertilizers play a significant role in Striga reproduction, calculations of the seed production per Striga plant indicated that considerable amounts of seeds were still added to the soil.Item Characterization of rice yellow mottle virus in north-eastern Tanzania(The University of Tokyo, 2015) Uke, Ayaka; Tibanyendela, Naswiru; Natsuaki, Keiko T; Sekiya, Nobuhito; Oizumi, NobuakiRice (Oryza sativa L.) is an important cereal-grain in some African countries and known to be attacked by Rice yellow mottle virus (RYMV). Rice plants with virus like symptoms were collected from lower Moshi and other areas in the north-eastern region of Tanzania. RYMV was detected by DAS- ELISA, RT-PCR and/or electron microscopy from almost all collected samples. Some RYMV isolates were sequenced and identified as strain S4. Also, three of them, Tz-12-20, Tz-12-22 and Tz-10-36, were clustered as a new group named S4-mk (Mt. Kilimanjaro). Cluster of S4-mk formed a monophyletic group of isolates in strain S4-lv reported from the Tanzanian side of the Lake Victoria. However, S4-mk and S4-lv lineages are separated from each other and S4-mk has the characteristic three amino acid substitutions. The isolates of S4-mk were also closely related to that of strain S4-mg. Amino acid sequences of the coat protein of the isolates in group S4-mk showed over 96% identity with those in other strain S4 varieties, S4-lv, S4-mg and S4-lm. The phylogenetic tree also indicated the possibility of strain S4-mk to have dispersed from south-western Kenya to north eastern Tanzania. As for the serotyping, followed by Fargette et al. (2002), these three isolates in S4-mk were classified into serotype 4.Item Design and fabrication of a centrifugal sunflower dehuller for improved sunflower oil and cake quality(Sokoine University of Agriculture, 2013) Robert MsafiriA study was conducted to examine the effect of dehulling sunflower seeds on oil extraction efficiency and cake quality. Specifically the study involved; design, fabrication and performance evaluation of a motorized centrifugal sunflower dehuller. Two sunflower seed varieties {Record and Kenya Fedha) were used in this study. The seed physical properties, machine design factors and operation conditions related to the dehulling process were studied and incorporated in the design, fabrication and performance evaluation phases of the developed centrifugal dehuller. The performance evaluation parameters of the designed dehuller included; throughput capacity, dehulling efficiency, kernel breakage and product yield. The dehuller was able to achieve a throughput capacity of 427 kg/h for Record variety and 513 kg/h for Kenya Fedha variety. Dehulling efficiency was SO % and 79.3 %, kernel breakage was 5.6 % and 2.5 %. while product yield was 70.3 % and 66.7 % for Record and Kenya Fedha varieties respectively. Dehulling improved oil quality and increased oil yield by 15.4 % for Record variety and by 14.6 % for Kenya Fedha variety. Dchulling significantly (p<0.05) increased crude protein content of the cake from 29.62 % to 44.49 % for Record variety and from 29.31 % to 44.94 % for Kenya Fedha variety. Also, dehulling significantly (p<0.05) reduced cake crude fiber from 33.41 % to 17.71 % and ether extracts from 16.62 % to 13.86 % for Record variety. The corresponding reductions of crude fiber and ether extracts for Kenya Fedha variety were 23.93 % to 17.35 % and 11.65 % to 10.56 %, respectively. Based on these results it is concluded that the use of the improved centrifugal dehuller can successfully improve oil extraction efficiency and cake quality produced by small and medium scale oil enterprises.Item Studies on the Influence of altitude on abundance of fall armyworm (Spodoptera Frugiperda (Je Smith)) (Lepidoptera: Noctuidae) in Tanzania(Discoveries in Agriculture and Food Sciences, 2025) Mbemba, Kiva F.; Rwegasira, Gration M.; Tryphone, George M.Fall armyworm (FAW) (Spodoptera frugiperda) is one of the most devastating polyphagous field crop pests in many parts of the world, including Tanzania. Influence of altitude on the abundance of S. frugiperda was studies by using Pheromone (Frugilure S. frugiperda, Chemtica international, S.A) embedded cup traps. The study was conducted along sites of Mt. Uluguru slopes including; SUA (525 masl), Mlali (579 masl), Mgeta (1050 masl) and Nyandira (1691 masl) located in Morogoro Region, Tanzania. A total of 16 cup traps (four at each site equidistantly arranged at 100 m apart) were used. Weather data were recorded using Hygrocron i-button hung on a tree at equidistant from the four traps. Data on S. frugiperda counts and weather variables were recorded weekly for duration of six months from January to June 2020. Results showed that S. frugiperda was abundantly recorded across he tested altitude albeit at varied abundance. There was significant difference (p < 0.001) among altitude on S. frugiperda abundance, whereby at low altitude, S. frugiperda abundance was high compared to medium and high altitude. Rainfall had positive correlation on S. frugiperda abundance (r = 0.16, r = 0.04) for SUA and Mlali and negative correlation (r = -0.44) and (r = -0.03) for Mgeta and Nyandira. Temperature had positive correlation (r = 0.21) on S. frugiperda abundance at Nyandira while SUA (r = -0.03), Mlali (r = -0.35) and Mgeta (r = -0.28) had negative correlation. Relative humidity for all four locations showed negative correlation with S. frugiperda abundance. Thus, appropriate and effective management practices of S. frugiperda should be considered throughout maize production areas and across crop production seasons regardless of the altitude.Item Effects of sowing dates and phosphorus levels on cotton growth and yield: soil analysis and implications(2023-11) Tlatlaa, Jacob Shauri; George Muhamba Tryphone; Eliakira Kisetu NassaryThis study assessed the effects of sowing dates and phosphorus levels on cotton performance in Chato-Msilale village in Chato District, Tanzania. The soil analysis revealed that field exhibited slightly acidic soil with normal electrical conductivity but suffered from severe deficiencies in total nitrogen and organic carbon. The same field presents common issue of low cation exchange capacity, indicating limited nutrient-holding capacity. Furthermore, both fields displayed very low levels of total nitrogen (<0.1%), signaling a nitrogen deficiency. Available phosphorus was rated as medium (16.8 mg kg−1 soil). Trace elements fluctuated and could be managed based on specific crop requirements. The factors at different levels were: (1) sowing dates – (i) 25th November 2022, (ii) 15th December 2022, and (iii) 4th January 2023; and (2) Phosphorus levels – (i) control, (ii) 20 kg P ha−1, (iii) 40 kg P ha−1, and (iv) 60 kg P ha−1. Regarding cotton growth and yield, sowing dates significantly (p < 0.001) influenced plant height, gin turnout, lint yield, number of bolls per plant, and boll weight while phosphorus levels did not exhibit significant effects. Earlier sowing dates resulted in higher yields, albeit with variations in yield components. Interactions showed that growth and yields were only numerically higher in the middle sowing date at higher levels of phosphorus applied. Overall, these insights offer valuable guidance for optimizing cotton cultivation in Chato District, emphasizing the importance of selecting appropriate sowing dates for improved yields.Item Effects of biopesticides on developmental biology of fall armyworm (spodoptera frugiperda (jesmith) (lepidoptera:noctuidae) in maize crops in Morogoro, Tanzania(Tanzania Journal of Agricultural Sciences, 2024) Simon, E; Kudra,A.B; Mwatawala, M.W.The Fall armyworm (Spodoptera frugiperda (J.E. Smith), is a highly mobile and polyphagous herbivore threatening crop production and the livelihoods of millions of smallholder farmers in the newly invaded areas in Africa, including Tanzania. 353 host plant species, principally Poaceae (maize, sorghum, rice, wheat, sugarcane, millet), Asteraceae (sunflower), Malvaceae (cotton), Fabaceae (soybean), families, groundnuts, potatoes, several fruit trees, ornamental plants, weed species, and vegetable crops are also hosts to FAW. This study aims to determine the effect of biopesticides on the developmental biology of FAW. A completely randomized design (CRD) was used to establish an experiment involving biopesticides; Bacillus thuringiensis Bt, Metarhizium anisopliae and Azadirachta indica seed extract each applied at a lower dose of 2 millimeters, 2 millimeters and 30gram per liter of water respectively, and tested against FAW in the laboratory. Each treatment was replicated four times. Results showed the developmental duration of FAW stages differed significantly between treatments. The time for each growth stage; egg incubation, larval, pupation and the total developmental were significantly longer (p < 0.001) in the biopesticides- treated colony compared to the untreated ones. The shortest developmental duration of FAW stages was observed on control colonies at 2.1 ± 0.18, 14.88 ± 0.18, and 27.7 ± 0.34 days for egg, larva and pupa stages respectively. The longest developmental duration of 3.5 ± 0.37, 22.03 ± 0.59, 12.68 ± 0.23 and 37.7± 0.54 days for egg, larva and pupa stages respectively was observed in colonies under B. thuringiensis treatment. These results confirmed that biopesticides can work effectively to keep FAW levels under control. Therefore, these are promising biocontrol alternatives to be included in the integrated pest management scheme.Item Characterization of selected rice genotypes from eastern and southern Africa tolerant to salinity at seedling stage(Sokoine University of Agriculture, 2024-05)Soil salinity stands as a prominent abiotic stress significantly impacting rice production and food security within sub-Saharan Africa. A promising strategy to mitigate this challenge involves the development and deployment of salinity-tolerant rice varieties. The objective of this study was to identify salinity-tolerant rice genotypes suitable for integration into breeding programs, offering a viable solution to salinity-affected soils in Eastern and Southern African rice-growing areas. The investigation focused on both phenotypic and genotypic characterizations of selected rice genotypes at the seedling stage, coupled with the identification of salinity tolerance- associated quantitative trait loci (QTLs). This research focused on analyzing a collection of 206 rice genotypes obtained from Tanzanian farmers' fields, along with other genotypes from Eastern and Southern Africa. genotypes were then subjected to phenotypic screening under a salinity level of 12 dS/m, utilizing a hydroponic system and following the established IRRI protocol. From this initial pool, 13 genotypes were carefully selected based on their SES scores to undergo more detailed evaluation of their growth and physiological characteristics. To identify the presence of the Saltol allele, a widely recognized QTL associated with salinity tolerance, genotypic analysis was performed using 1k- RiCA SNP markers. Phenotypic screening revealed salinity's adverse effects on various growth parameters, particularly on root and shoot dry weights, indicative of osmotic imbalance. Correlation analysis identified sodium concentration, sodium-to-potassium ratio, and canopy temperature as strong indicators of salinity tolerance in rice genotypes. These variables hold as potential physiological markers for salinity tolerance screening in breeding programs. Principal Component Analysis (PCA) was employed to identify key variables for salinity tolerance, revealing potassium ratio, root dry weight, shoot dry weight, shoot length, and survival as significant contributors. Based on PCA results, genotypes were classified into tolerant, moderately tolerant, and sensitive categories. Six moderately tolerant genotypes (Intsindagira Bigega, K5, SATO 1, Sukari, Terembele (LL 29), and ZX 117) exhibited promising phenotypic tolerance, making them potential candidates for enhancing salinity tolerance in rice varieties. Concurrently, Genotypic evaluation at the seedling stage provided insights into the expression of salinity-tolerant traits among the rice genotypes. Remarkably, 36 rice genotypes were found to possess the Saltol allele, recognized for its role in conferring salinity tolerance. some Saltol-possessing genotypes exhibited inadequate performance under salinity stress conditions. Interestingly, 16 genotypes lacking the Saltol allele demonstrated salinity tolerance, suggesting the presence of other genetic factors (QTLs) contributing to this trait beyond Saltol. Additionally, the geographical distribution of Saltol-possessing genotypes within Tanzania revealed variations across different Agro-ecological zones. Notably, the Coastal Zone exhibited a higher proportion of phenotypically tolerant genotypes compared to other zones, suggesting local farmers' continuous selection pressure as a possible contributing factor. These findings highlight the potential for integrating diverse salinity-tolerant rice genotypes, possessing various genetic mechanisms, into breeding programs. This approach could lead to the development of novel rice varieties capable of thriving under salinity stress conditions.Item Viability and genetic integrity of African eggplant (Solanum spp.)seeds during natural ageing under cold dry storage(Sokoine University of Agriculture, 2024) Jonas Nickas; Sognigbé N'Danikou; Abdul J. Shango; Newton KilasiSeed deterioration occurs gradually during long-term seed storage. Viability, vigour, and genetic integrity of African eggplant seeds were assessed under natural ageing during genebank storage. The percentage of tail DNA before and after seed imbibition was used to account for genotoxicity and DNA repair during cold dry storage at 10 °C using the comet assay. After 2, 5, and 12 years of storage in the genebank, a reduction of seed viability was observed in all studied African eggplant genotypes. However, seed viability was more significantly reduced in seed lots that had been stored for a longer period in the genebank (p < 0.05). Overall, higher viability loss was recorded in seeds regenerated 12 years before (p < 0.05). The molecular analysis by comet assay showed significant DNA damage during natural aging under genebank conditions, accompanied by important loss of viability and germination energy in older seeds translated into low DNA repair after seed imbibition. The seed lots which had better initial quality were able to maintain higher viability during genebank storage. The findings inform on the storage behaviour of African eggplant genotypes and are relevant for the proper handling of seed lots in genebanks. They are also relevant for future studies on seed longevity prediction in African eggplant.Item Effects of soil pH levels on iron and zinc concentrations of common bean (Phaseolus vulgaris L.) genotypes(African Journal of Agricultural Research, 2024-07) Magomere, Kinguye Masamaki; Nchimbi-Msolla, Susan; Tryphone, George MuhambaPlants grown in acid soils experience a variety of stresses which include aluminium, hydrogen and/or manganese toxicity, as well as nutrient deficiencies of calcium and magnesium. A study was carried out to determine the influence of soil pH levels on iron and zinc concentrations in leaves and seeds of twenty-five common bean genotypes. Plastic cups trial was carried out in the screen house to determine the actual amount of quick lime Ca(OH)2 required to reach a targeted soil pH level. In each pot, 4 kg soil was amended with Ca(OH)2 to obtain the target soil pH levels of 5.3, 5.5, 6.5 and 7.5. The experimental design followed a randomized complete block design in a split plot arrangement with three replications per treatment. The pH levels were treated as main factor and genotypes as sub plot. Data collected include leaf iron concentration, seed iron concentration, leaf zinc concentration, and seed zinc concentration and analysis of variance was performed for all data using GenStat statistical package 15th edition. The result demonstrated that soil pH affects absorption of micronutrients directly or indirectly by affecting the nutrients availability to common bean plants.Item Unexplored agronomic, socioeconomic and policy domains for sustainable cotton production on small landholdings: a systematic review(Frontiers in Agronomy, 2023-11-20) Tlatlaa, Jacob Shauri; Tryphone, George Muhamba; Nassary, Eliakira KisetuCotton productivity continues to be disputed, despite rapid advancements and widespread technologies. These uncertainties remain to be critically addressed in a broad spectrum focusing on domains at the global level. Therefore, this systematic review provides an overview of the existing advancements in knowledge, skills, and technologies for sustainable cotton production on small landholdings. Specifically, the areas of the cotton chain examined are threefold: - (1) Explore disguised agronomic practices to be endowed for sustainable cotton production on small landholdings; (2) Explore socioeconomic settings based on their disparities in contributing to sustainable cotton production on small landholdings; and (3) Explore existing and feasible institutional policies to be enforced for sustainable cotton production on small landholdings. This review shows that worldwide cotton production involves conventional and organic systems, at the expense of the traditional system. Heavy uses of nitrogenous fertilizers and pesticides are the common practices in conventional systems, with some adoptions of precision agriculture practices, and genetically modified varieties. Rotation and intercropping with early-maturing food crops are also identified viable options to improve farmers’ attitudes toward adopting cotton- producing technologies. In socioeconomics, farmers’ livelihoods are improved by income generation from sales of cotton and labour in the cotton industry. Gender equity in the cotton industry prioritizes females over males, as females display a group with a higher level of technology adoption. Generally, clear institutional policies governing the cotton industry are globally paucity. Furthermore, efforts to sensitize sustainable cotton production are still highly questionable and challenged by the superseding climate changes.Item Effects of sowing dates and phosphorus levels on cotton growth and yield: soil analysis and implications(Frontiers in Sustainable Food Systems, 2023-11-20) Tlatlaa, Jacob Shauri; Tryphone, George Muhamba; Nassary, Eliakira KisetuThis study assessed the effects of sowing dates and phosphorus levels on cotton performance in Chato-Msilale village in Chato District, Tanzania. The soil analysis revealed that field exhibited slightly acidic soil with normal electrical conductivity but suffered from severe deficiencies in total nitrogen and organic carbon. The same field presents common issue of low cation exchange capacity, indicating limited nutrient-holding capacity. Furthermore, both fields displayed very low levels of total nitrogen (<0.1%), signaling a nitrogen deficiency. Available phosphorus was rated as medium (16.8 mg kg−1 soil). Trace elements fluctuated and could be managed based on specific crop requirements. The factors at different levels were: (1) sowing dates – (i) 25th November 2022, (ii) 15th December 2022, and (iii) 4th January 2023; and (2) Phosphorus levels – (i) control, (ii) 20 kg P ha−1, (iii) 40 kg P ha−1, and (iv) 60 kg P ha−1. Regarding cotton growth and yield, sowing dates significantly (p < 0.001) influenced plant height, gin turnout, lint yield, number of bolls per plant, and boll weight while phosphorus levels did not exhibit significant effects. Earlier sowing dates resulted in higher yields, albeit with variations in yield components. Interactions showed that growth and yields were only numerically higher in the middle sowing date at higher levels of phosphorus applied. Overall, these insights offer valuable guidance for optimizing cotton cultivation in Chato District, emphasizing the importance of selecting appropriate sowing dates for improved yields.Item Studies on the influence of altitude on abundance of fall armyworm (spodoptera frugiperda (Je Smith)) (lepidoptera: noctuidae) in Tanzania(Society for Science and Education, 2023-08-25) Mbemba, Kiva F.; Rwegasira, Gration M.; Tryphone, George M.Fall armyworm (FAW) (Spodoptera frugiperda) is one of the most devastating polyphagous field crop pests in many parts of the world, including Tanzania. Influence of altitude on the abundance of S. frugiperda was studies by using Pheromone (Frugilure S. frugiperda, Chemtica international, S.A) embedded cup traps. The study was conducted along sites of Mt. Uluguru slopes including; SUA (525 masl), Mlali (579 masl), Mgeta (1050 masl) and Nyandira (1691 masl) located in Morogoro Region, Tanzania. A total of 16 cup traps (four at each site equidistantly arranged at 100 m apart) were used. Weather data were recorded using Hygrocron i-button hung on a tree at equidistant from the four traps. Data on S. frugiperda counts and weather variables were recorded weekly for duration of six months from January to June 2020. Results showed that S. frugiperda was abundantly recorded across he tested altitude albeit at varied abundance. There was significant difference (p < 0.001) among altitude on S. frugiperda abundance, whereby at low altitude, S. frugiperda abundance was high compared to medium and high altitude. Rainfall had positive correlation on S. frugiperda abundance (r = 0.16, r = 0.04) for SUA and Mlali and negative correlation (r = -0.44) and (r = -0.03) for Mgeta and Nyandira. Temperature had positive correlation (r = 0.21) on S. frugiperda abundance at Nyandira while SUA (r = -0.03), Mlali (r = -0.35) and Mgeta (r = -0.28) had negative correlation. Relative humidity for all four locations showed negative correlation with S. frugiperda abundance. Thus, appropriate and effective management practices of S. frugiperda should be considered throughout maize production areas and across crop production seasons regardless of the altitude.Item Genetic parameters estimate of iron and zinc nutrients in common bean genotypes(African Journal of Agricultural Research, 2024-06) Magomere, Kinguye Masamaki; Nchimbi-Msolla, Susan; Tryphone, George MuhambaThere is need to know the heritability of different traits for the effective selection of parents for future breeding activities. A study was carried out to determine heritability of iron and zinc in common bean. Crosses were made with each donor and recipient parents to obtain four different types of crosses. Part of the F1 seed from each cross was sown in the screen house to produce F2 seeds and also backcrossed to both parents. Heritability was estimated using backcross method for high broad sense heritability and narrow-sense heritability. Broad sense heritability for progenies of NUA 11 × Zawadi (56%), NUA 11 × Pesa (76%), NUA 17 × Zawadi (57%) and NUA 17 × Pesa (59%) were obtained. Narrow sense heritability estimates for progenies of NUA 11×Zawadi, NUA 11 × Pesa, NUA 17 ×Zawadi and NUA 17 × Pesa were 65%, 71%, 79% and 63%, respectively. Genetic advance (GA) values for NUA 17 × Zawadi, NUA 11 × Pesa, NUA 17 × Pesa and NUA 11 × Zawadi was 35, 12.3, 3.5 and 1%, respectively. This study demonstrates that there is a potential for improvement of concentration of iron and zinc in common bean genotypes. Therefore, selection of a superior genotype on the basis of its phenotypic performance, heritability of traits could be well exploited.Item Evaluating limitations of agroecological practices and stakeholders’ response: a Case of Uluguru mountains landscape in Morogoro municipality, Tanzania(East African Journal of Science, Technology and Innovation, 2023-09-14) Tryphone, G. M.; Pastory, S. T.In Sub-Saharan Africa, conventional farming is associated with intensive use of synthetic chemicals and inputs to maximize agricultural productivity. This is done at the expense of sustainable agroecologically based production systems. This objective was to describe limitations of agroecological practices and stakeholders’ response along Mountain Uluguru. The area has been vulnerable to unregulated land degradation aggravated by soil erosion largely due to unsuitable agricultural practices. The data were collected through questionnaires and in-depth interviews from 72 respondents who were purposively selected. Both qualitative and quantitative data were analysed using content analysis and statistical software respectively. Farmers undertake agriculture to increase production so as to meet food needs (44.8%) and employment opportunities (55.2%). About 41.7% of farmers who had land with secure tenure grew fruit and non-fruit trees on their farms or homesteads, 11.7% rented the farming land temporarily from owners through informal arrangements and the rest squatted on public land for cultivation of vegetables. From SWOT analysis, agroforestry is threatened by unregulated agricultural activities (18.6%) and overuse of forest resources unsustainably (7.0%). The agroecology training is not coordinated and supported by government agencies, which have authority to inform the policy makers about insecure land tenure and unavailability of organic inputs that would increase farmers’ livelihoods. Agro-soil erosion control and conservation agriculture measures are essential features of agroecology training, but some farmers were not aware of them and those who are aware do not adopt them effectively. The study concludes that, without the government acknowledgement of agro-ecology and its associated contributions there will always be weak institutional coordination among stakeholders required to regulate, promote and support agro-ecology practices to create a balance of conserved environment, protected ecology and enhanced farmers’ livelihoods. This is because there is no clear national guidelines and support (financial and technical) addressing the challenges facing agro-ecology practice yet.Item Impact of sowing date and level of phosphorus application on economic returns in cotton(Frontiers in Plant Science, 2024-06-12) Tlatlaa, Jacob Shauri; Tryphone, George Muhamba; Nassary, Eliakira KisetuThis study explored the economic dynamics of cotton (Gossypium hirsutum L.) production in Msilale village, Chato District, Tanzania. The experiment utilized a factorial design with sowing dates on November 25th, December 15th, and January 4th, and phosphorus levels at 0, 20, 40, and 60 kg P ha-1, replicated three times. Results indicated significantly higher cotton yields (6.1 t ha-1 and 6.3 t ha-1) for November and December sowings compared to January (3.8 t ha-1). This is a 61% and 66% increase in cotton yields for November and December sowings, respectively relative to January sowing. Though not significant, 20 kg P ha-1 and 40 kg P ha-1 applications yielded 5.8 t ha-1 and 5.4 t ha-1, respectively, while 60 kg P ha-1 yielded 5.3 t ha-1. This is a 9.4% and 1.9% increase in cotton yields at 20 and 40 kg P ha-1, respectively relative to absolute control and 60 kg P ha-1 application. Economic analysis revealed that late sowing (January) had the lowest net profit (Tshs. 3,723,400 ≈ USD 1,486) and benefit-to-cost ratio (BCR) of 11.2. Early sowings recorded higher net profits (Tshs. 6,679,527 ≈ USD 2,666 and Tshs. 6,861,283 ≈ USD 2,738) and BCRs (18.4 and 18.8, respectively). This is a 79% (BCR = 64%) and 84% (BCR = 68) increase in net benefits from early sowings compared to late sowing. Applications of 20, 40, and 60 kg P ha-1 resulted in net benefits of Tshs. 5,452,572 ≈ USD 2,176 (BCR = 19.2), Tshs. 5,209,904 ≈ USD 2,079 (BCR = 15.1), and Tshs. 5,748,786 ≈ USD 2,294 (BCR = 14.1), respectively, with a significant (p = 0.017) BCR at 20 kg P ha-1 indicating cost-effectiveness. This is a 36% and 7.1% economic benefit at 20 and 40 kg P ha-1, respectively compared to 60 kg P ha-1 application. Optimizing sowing dates and P levels can boost economic returns in cotton production and promote sustainability.Item Improving cotton fiber quality through strategic sowing: implications for phosphorus management from experiments in Chato district, Tanzania(Journal of Natural Fibers, 2024) Tlatlaa, Jacob Shauri; Tryphone, George Muhamba; Nassary, Eliakira KisetuThis study was conducted in Msilale Village, Chato District in Tanzania, to evaluate the influence of sowing dates and phosphorus levels on cotton fiber quality. The study was established according to a factorial trial, with varying sowing dates (25th November 2022, 15th December 2022 and 4th January 2023) and phosphorus levels (control, 20 kg P ha−1, 40 kg P ha−1, 60 kg P ha−1). Results revealed that early planting had a statistically signifi cant (p < .001) effect on fiber cotton quality, including spinning coefficient index, fiber length, fiber strength, uniformity index, short fiber content, and grade/color. Early sowing dates (25th November 2022 and 15th December 2022) consistently produced superior fiber quality, including spin ning coefficient index (156.5 and 148.4), moisture content of the fiber (7.8% and 7.7%), micronaire (3.5 μg/inch), upper half mean length (1.2 cm), unifor mity index (84.6% and 84.2%) and shorter fiber (6.8% and 7.0%) relative to late sowing (4th January 2023). Conversely, phosphorus levels did not sig nificantly (p > .05) impact these parameters within the tested range. This research underscores the critical role of selecting appropriate sowing dates for cotton cultivation to achieve better fiber quality.Item Effect of integrated weed control options on growth and yield of cassava at Kilosa district, Tanzania(Society for Science and Education, 2023-12-25) Leonard, Joseph Adonia; Laswai, Emmanuel Vicent; Kudra, Abdul B.; Tryphone, George M.Weeds are among of the major pest that hinders cassava growth and production. Also, weeds can host insect and disease pathogens, thus brings up difficulty in the growth of cassava. The effect of different weed control treatment combinations was studied at Ilonga village, Kilosa district during 2019/2020 planting season. Till only and till + Ridge, pre-emergence herbicides (Primagram Gold a.i 290 g/L S- metolachlor + 370 g/L atrazine and Oxfen a.i Oxyfluorfen 24% EC), post emergence herbicides (Force up a.i 480 g/L of Glyphosate-Isopropylamine salt and back pack weeder with modified tines were tested on Cassava variety Kiroba in a factorial experiment arranged in a randomized complete block design (RCBD) replicated three times. Combination of tillage practices and pre-emergence herbicides application increased number of days weeds took to re-emerge. The correlation analysis showed a highly significant strong positive relationship, r = 0.925, p < 0.001 and r = 0.781, p < 0.05 between cassava stem height and cassava fresh root weight, and cassava stem girth and cassava fresh root weight, respectively. Weed control combinations did not significantly affect the cassava fresh root weight, p = 0.514 and cassava biomass p = 0.732. Also weed control combinations did not significantly affect soil quality. The combination of till + ridges, application of S-metolachlor + atrazine herbicides and glyphosate provided favorable environment for cassava growth and root formation as compared to other treatment combinations. Therefore, it is recommended as a best option for controlling weeds in cassava production system.Item Effects of yellow witchweed (Alectra vogelii) strains on performance of improved cowpea (Vigna unguiculata (L) Walp.) Genotypes(Greener Journal of Agricultural Sciences, 2021-12-31) Reuben, F.M.; Tryphone, G.M.; Kudra, A.B.Witchweed (Alectra vogellii) has continuously remained a great challenge for cowpea production in sub-Saharan Africa. Developing resistant and stable high yielding cowpea genotypes in Alectra infested areas requires evaluation of available cowpea germplasm for resistance against the weed. To achieve this, an experiment was conducted in the screen house at Ilonga Agricultural Research Institute (ARI- Iloga), Tanzania in 2017 to determine how selected cowpea genotypes fair in soils infested with different Alectra strains. The experiment comprised of two factors namely A. vogellii strains as the main factors and cowpea genotypes as sub-factors and was carried out as a spilt plot experiment arranged in randomized complete block design with three replications. Results revealed significant differences amongst cowpea genotypes on days to first Alectra emergence and number of emerged Alectra shoots. The cowpea genotypes B 301, Mkanakaufiti, Vuli AR1, Vuli AR2 and Vuli-1 allowed Alectra emergence at 42.83, 37.25, 36.75, 37.42 and 33.17 days after planting (DAP), respectively. There were variations in number of Alectra shoots supported by genotypes, as 1.0, 5.0, 4.0, 5.0 and 14.0 for B301, Mkanakaufiti, Vuli AR1, Vuli AR2 and Vuli-1, respectively. The genotype B 301 recorded the lowest number of Alectra shoots, reached 50% flowering earlier and had the highest seeds and pods weight and highest number of pods per plant. Contrarily, the genotype Vuli-1 produced the highest number of seeds per pod and was the first to reach 95% physiological maturity. The genotype B 301 was identified to possess a high level of resistance to A.vogelii infestation and accordingly was deemed as a useful source of resistance genes in cowpea resistance breeding programs.Item Selecting for coupling-phase recombination between potyvirus resistance and white endosperm colour in maize preferred by farmers in sub-saharan Africa (SSA)(Afrika focus, 2019) Bulegeya, Victoria B.; Jones, Mark W.; Muhamba, Tryphone G.; Das, Biswanath; Thomison, Peter R.; Francis, David M.; Redinbaugh, Margaret. G.Maize lethal necrosis (MLN) disease caused by a combined infection of Maize chlorotic mottle virus (MCMV) and any cereal infecting potyvirus is a threat to food security in Sub-Saharan Africa (SSA). Resistance to potyvirus has been extensively studied and Mdm1 gene for potyvirus resistance on chromosome 6 of maize is linked to Y1 gene for maize endosperm colour. This study is aimed at se- lecting for coupling-phase recombination of potyvirus resistance and white endosperm colour. White susceptible maize lines CML333 and CML277 were crossed with a yellow resistant line, Pa405, to produce F1 and F2 progenies. Progenies were screened using molecular markers to recover 22 white endosperm recombinants. 22 selections were advanced to F3 recombinant families, and 10 were as- sayed for their responses to Maize dwarf mosaic virus (MDMV) and Sugarcane mosaic virus (SCMV). Four families segregated for SCMV resistance, selection of homozygous recombinants within these families will provide lines appropriate for improving lines with resistance to SCMV and MLN resistance in SSA.