Bio

Prof. OLUBAYO FLORENCE M.

An Agricultural Scientist and Associate Professor with emphasis in Integrated Crop Pest management, Post harvest pest management and Agricultural Technology transfer. I have wide research experience in crop protection systems as a result of own research and that with graduate students, I am familiar with the major crops and livestock production systems in the country.

PDF Upload: 

Publications


2016

2015

V.M., K, M. K, F O, G.M K, Nderitu JH.  2015.  A logit Analysis of Farmer knowledge on Rice Blast Disease Pyricularia grisea (Cook, Sacc) at Mwea Irrigation Scheme, Kirinyaga County, Central Province, Kenya. . Universal Journal of Agricultural Research. 3(3):114-117..
Julius J. Okello, Margaret J. Hutchinson, AM'ombe JAFOMM.  2015.  Consumer Demand for Value-added Products of African Indigenous Vegetables in Coastal Kenya: The Case of Sun-dried and Frozen Cowpea Leaves.. Journal of Agriculture, food systems, and community Development. . :1-18.

2014

Were, HK, Kabira JN, Kinyua ZM, Olubayo FM, Karinga JK, J.Aura, Lees AK, Cowan GH, Torrance L.  2014.  Occurrence and Distribution of potato pests and diseases. . Potato Research, online publication..
Mutonyi, J, Shibairo SI, Chemining’wa GN, Olubayo FM, Nyongesa HW.  2014.  Sugarcane response to liming, manuring and inorganic fertilizers on acid acrisols in western Kenya. . International Journal of Recent Scientific Research . 5(9):1703-1707.
Likhayo, P, Olubayo F., Ngatia C.  2014.  Methyl Bromide Alternatives for Maize Grain Storage in Kenya. . International Journal of Science and Research.. 3(7):2348-2352.

2013

Muthomi, JW;, Nderitu JH;, Olubayo FM;, Kabira JN;, Cheminin’wa GN;, Kiretai SM;, Aura JA;, Muindi EM.  2013.  Management Of Potato Viruses In Seed Potato Production Using Border Crops. Abstract

Field experiments were conducted over two croppi ng seasons to investigate the effectiveness of border crops in managing potato aphids and the associated viruses in seed potato production. Potato plots were surrounded with maize, sorghum and wheat borde rs. Aphid population was monitored on leaves and on yellow sticky traps. Other data collected included virus disease incidence and tuber yield. The border crops reduced aphid popula tion on leaves compared to non-bordered potato plots. More alate aphids we re caught on yellow sticky traps placed inside potato plots than on traps placed inside the border crops. In addition, virus disease incidence was reduced in all plots surrounded by the border cr ops. However, plots surrounded by border crops had reduced tuber yield, although the yield of s eed grade was increased. The results indicated that use of border crops would be beneficial in the management of virus diseases in small-holder seed potato production.

Kega, VM, Kasina M, Olubayo F, Nderitu JH.  2013.  Management of Maliarpha separatellA Rag Using Effective Entomopathognic Nematodes and Resitant Rice Cultivars.. Journal of Entomology. :1-7.

2012

M., DROLUBAYOFLORENCE.  2012.  Gchu S. M., Muthomi J. W, Narla R. D., Nderitu J. H. Olubayo F. M, Wagacha J. M. Management of thrips (Thrips tabaci) in bulb onion by use of vegetable intercrops. International Journal of AgriScience Vol. 2(5): 393-402, May 2012. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Field experiments were conducted between July 2008 and May 2009 to evaluate the effectiveness of intercropping carrot (Daucus carata), spider plant (Cleome gynandra) and French bean (Phaseolus vulgaris) with onion in the management of thrips (Thrips tabaci) in onion. Each of the three onion varieties, Bombay Red, Red Creole and Orient F 1 were intercropped with each of the vegetables and insecticide imidacloprid was used as a standard check. Thrips damage incidence and severity were determined every 7 days with damage severity being estimated on a scale of 1-5. Total and marketable bulb yield were determined at physiological maturity. Intercropping onion with spider plant and carrot significantly (p S; 0.05) reduced thrips population by up to 45.2% and 21.6%, respectively but French bean had no significant effect. The three vegetable intercrops significantly (p S; 0.05) reduced thrips damage severity, with spider plant having the greatest reduction of up to 15.7%. Inter cropping onion with carrot and spider plant significantly (p S; 0.05) reduced onion bulb yield while the effect of French bean and imidacloprid on yield was not significant (p S; 0.05). This study showed that spider plant and carrot can be utilized in the management of onion thrips. However, further investigations should be undertaken on their optimal spatial arrangement in an intercropping system to avoid reduction in bulb yield and, therefore, achieve optimum onion productivity. Keywords: Allium cepa, Daunts carota, Cleome gynandra, intercropping, Phaseolus vulgaris. Thrips tabaci  

2011

Were, S;, Olubayo F;, Nderitu JH;, Kilalo D;, Koech A.  2011.  Resistance of potato varieties to potato tubermoth (phthorimaea opercullela (Zeller)..
Muthomi, JW;, Muinde EM;, Nderitu JH;, Olubayo FM;, Kabira FM.  2011.  Integrated management of aphid-transmitted viruses in potato (Solanum tuberosum L.).
Muthomi, JW, Kinyungu TN, Nderitu JH, Kabira JN.  2011.  Spatial Arrangement Of Maize As Border Crop To Manage Aphids And Aphid-Transmitted Viruses In Potato. Abstractabstract4.pdfWebsite

Field experiments were conducted over two growing seasons to determine the effect of spatial arrangement of maize as border crop to manage aphid infestation and aphid-transmitted virus diseases in potato (Solanum tuberosum L.). Maize was planted at a distance of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 m from the potato crop. Aphid infestation and incidence of virus infection was monitored over the growth period of potato. Aphids were recorded on potato leaves and in water pan traps while virus infection was determined by visual symptoms on the potato plant. At harvest, potato tubers were graded into ware, seed, and chatts and weighed. The results show that placement of maize border up to 0.5 m and 1.0 m reduced aphid population and virus disease incidence by up to 48%. The maize borders had no effect on the yield of seed potato grade but only on the ware. Placing maize border at 0.5m had the greatest reduction of ware potato yield by 48%. Maize borders placed up to 1m from the potato crop would be effective in the management of potato aphids and aphid-transmitted virus diseases. This study shows that the technology would be ideal for propagation plots in small scale seed potato production.

M., DROLUBAYOFLORENCE, M. DROLUBAYOFLORENCE, M. DROLUBAYOFLORENCE, M. DROLUBAYOFLORENCE, M. DROLUBAYOFLORENCE.  2011.  F. OLUBA YO, D. KILALO, S. OBUKOSIA, S. SHIBAIRO AND M. KASINA. HOMOPTERAN PESTS COMPLEX OF CITRUS (Citrus sinensis) IN SEMI-ARID KENYA. International Journal of Sustainable Crop Production (IJSCP). 6 (2):23-28(August 2011). : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} On farm studies in collaboration with farmers who grow citrus were conducted in upper midlands and lower midlands agro- ecological zones in Machakos district Kenya. The aim of the study was to understand the factors affecting population fluctuations of homopteran pests attacking citrus in Kenya. White flies (Aleurothrixus flocossus Maskell) and black flies (Aleuroeanthus woglumi Ashby) were the most common pests of citrus observed throughout the monitoring. Aphids (Toxoptera citricidus Kirk.) and psyllids (Triozae erytreae Del Guercio) were occasional pests while scales (various) were rare attacking only a few plants within the farms. Time period of sampling had an effect on whitefly, psyllid and blackfly populations. Aphid populations were not affected by the sampling time period. However, there were ecological differences in the development of aphid, blackfly and psyllid populations. 11 has been observed that populations of homopteran pests on citrus trees do vary with time. There was one major flush period of the citrus trees during the monitoring period. High aphid and psyllid populations seemed to coincide with the flush period. Flushing of the trees may have contributed in the variation of the pest populations that were being monitored. These findings are discussed in relation to their possible use in  the development of integrated pest management (IPM) strategies for the management of these pests. Key words: aphid, psyllid, blackflies, whiteflies, monitoring, IPM,flush growth
M., DROLUBAYOFLORENCE.  2011.  F. Olubayo, D. Kilalo, S. Obukosia, S. Shibairo and M. Kasina. Homopteran pests complex of citrus (Citrus cinensis) in Semi- Arid Kenya. Int. J. Sustain. Crop Prod. (2): 23- 28 August, 2011. International Journal Sustainable Crop Production. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Field experiments were conducted between July 2008 and May 2009 to evaluate the effectiveness of intercropping carrot (Daucus carata), spider plant (Cleome gynandra) and French bean (Phaseolus vulgaris) with onion in the management of thrips (Thrips tabaci) in onion. Each of the three onion varieties, Bombay Red, Red Creole and Orient F 1 were intercropped with each of the vegetables and insecticide imidacloprid was used as a standard check. Thrips damage incidence and severity were determined every 7 days with damage severity being estimated on a scale of 1-5. Total and marketable bulb yield were determined at physiological maturity. Intercropping onion with spider plant and carrot significantly (p S; 0.05) reduced thrips population by up to 45.2% and 21.6%, respectively but French bean had no significant effect. The three vegetable intercrops significantly (p S; 0.05) reduced thrips damage severity, with spider plant having the greatest reduction of up to 15.7%. Inter cropping onion with carrot and spider plant significantly (p S; 0.05) reduced onion bulb yield while the effect of French bean and imidacloprid on yield was not significant (p S; 0.05). This study showed that spider plant and carrot can be utilized in the management of onion thrips. However, further investigations should be undertaken on their optimal spatial arrangement in an intercropping system to avoid reduction in bulb yield and, therefore, achieve optimum onion productivity. Keywords: Allium cepa, Daunts carota, Cleome gynandra, intercropping, Phaseolus vulgaris. Thrips tabaci  

2010

Muthomi, JW;, Kinyungu TN;, Nderit JH;, Olubayo FM;, Kabira JN.  2010.  Effect Of Maize Border Crop Placement Distance On Aphid Population And Aphid-transmitted Virus Diseases In Potato..
M., DROLUBAYOFLORENCE.  2010.  F. OLUBA YO, A. KlBARU, J. NDERlTU, R. NJERU AND M. KASINA MANAGEMENT OF APHIDS AND THEIR VECTORED DISEASES ON SEED POTATOES IN KENYA USING SYNTHETIC INSECTICIDES, MINERAL OIL AND PLANT EXTRACT. . Innov. Dev. Strategy 4(2), 1-5. (December 2010). : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

2009

Muthomi, JW;, Nyaga JN;, Olubayo FM;, Nderitu JH;, Kabira JN;, Kiretai SM;, Aura JA;, Wakahiu M.  2009.  Incidence Of Aphid Transmitted Viruses In Farmer Based Seed Production In Kenya.
Muindi, EM, Muthomi W, Nderitu, John H, Kabira JN, Chemining'wa GN, Kiretai SM, Aura JA.  2009.  Use of cereal border crops in management of aphid-transmitted viral diseases during seed potato (Solanum tuberosum) production. AbstractWebsite

A field experiment was conducted over two cropping seasons to investigate the effectiveness of cereal border crops in managing potato aphids and the associated viruses during seed potato production. Potato plots were surrounded with maize, sorghum or wheat borders. Aphid population was monitored on leaves and on yellow sticky traps. Other data collected included viral disease incidence and tuber yield. The border crops reduced aphid population on leaves compared to non-bordered potato plots. More alate aphids were caught on yellow sticky traps placed inside potato plots than on traps placed inside the border crops. In addition, viral disease incidence was reduced in all plots surrounded by the border crops. However, plots surrounded by border crops had reduced tuber yield, although the yield of seed grade was increased. Thus use of border crops is beneficial in management of viral diseases during seed potato production.

Nderitu, JH, Kibaru A, Njeru R, Yobera D, Kasina M.  2009.  Utilization Of Border Crops To Manage Aphid Colonization And PVY Incidence On Potato(Solanum tuberosum L). AbstractWebsite

Sorghum (Sorghum bicolorL.), wheat (Triticum aestivumL.), maize(Zea MaysL.), common bean (Phaseolus vulgaris L.) and garden pea (Pisum sativumL.) were tested as border crops for their ability to reduce the number of colonizing aphids and Potato Virus Y (PVY) incidence in seed potatoes (Solanum tuberosumL.). The experiment was done at Tigoni, Central Kenya for two seasons, from 03 May 2002 and from 17 October 2002. Apterae aphids were monitored weekly by picking 15 leaves from 5 randomly selected plants per plot while alate aphids were collected using yellow sticky traps mounted 0.5 m from the ground level at the edge of border crops. Three aphid species were recorded: Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer). PVY incidence in the inner rows of potatoes surrounded by fallow and the border crops was statistically insignificant (P>0.05) but outer rows in crop-bordered plots had significantly less PVY than outer rows of fallow-bordered plots. The DAS- ELISA test used to confirm presence of PVY showed that the disease had the highest and lowest incidence in fallow and wheat bordered plots, respectively. This study shows that the effective border-crops can be used to manage aphids and PVY disease in potatoes. In addition, since most Kenyan potato growers are low income earners, adoption of border cropping technology can improve immensely the production success of the crop

Kasina, M, Nderitu J, Yobera D, Obudho E, Watura C.  2009.  Within-plant distribution and seasonal population dynamics of flower thrips (Thysanoptera: Thripidae) infesting French beans (Phaseolus vulgaris L.) in Kenya. Abstract

The aim of this research was to study spatial distribution of flower thrips on French beans (Phaseolus vulgaris L.) in Kenya. Their build up and seasonal population dynamics was monitored using sticky blue colour traps and sampling of leaves and flowers in two seasons in 2002. Thrips infested French beans from the second week after crop emergence. Their population peaked at peak flowering. The sticky trap catches were linearly related to the actual presence of thrips on the crop and could estimate population build up of adult thrips on leaves and flowers. On the plants, most adults were on flowers. Larvae mainly inhabited leaves, buds and pods. The two thrips species, Frankliniella occidentalis (Pergande) and Megalurothrips sjostedti Trybom were spatially separated. The former colonized lower-canopy leaves and early flowers while the latter inhabited middle-canopy leaves and mature flowers. Overall, M. sjostedti was less than 5% of the total thrips population, implying that F. occidentalis was the main thrips pest of French beans. This study suggests that French bean growers should monitor thrips population before initiating any control measure. In addition, they should commence thrips control early, at pre-flowering, using larvicides to reduce the thrips pool and their migration to flowers. A combination of monitoring with sticky traps and proper sampling would contribute to sustainable thrips management.

2008

M., DROLUBAYOFLORENCE.  2008.  Agnes W. Mwang. International Journal of Sustainable Crop Production 3(5): 40- 45.. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4
M., DROLUBAYOFLORENCE.  2008.  F.Olubayo, A.Kibaru, J.Nderitu, R.Njeru, S.Shibairo and M.Kasina 2008. Management of Aphids and Aphid Transmitted virus in stored seed potatoes in Kenya. International Journal of Sustainable Crop Production 3(5): 40- 45.. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4
M., DROLUBAYOFLORENCE.  2008.  14. Johnson O. Nyasani; John W. Kimenju; Florence M. Olubayo and Michel J. Wilson. (2008). Laboratory and field investigations using indigenous entomopathogenic nematodes for biological control of Plutella xylostella in Kenya.. Asian Journal of plant pathology 2(1) 48-53.. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4
M., DROLUBAYOFLORENCE.  2008.  A.K. Chirchir, J.W.Kimenju, F.M. Olubayo and G.K. Mutua 2008. Abundance and distribution of Plant parasitic Nematodes associated with sugarcane in Western Kenya.. Asian Journal of plant pathology 2(1) 48-53.. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

2007

Nyaga, JN;, Muthomi JW;, Olubayo FM;, Nderitu JH.  2007.  Seed potato production and occurrence of Transmitted viruses in Nyandarua District.
Nderitu, JH;, Wambua E;, Olubayo F;, Kasina J;, Waturu C.  2007.  Evaluation of pesticide/variety combinations for thrips (Thysanoptera: Thripidae) management on French beans (P. vulgaris L.) in Kenya. Abstract

A field study was undertaken to evaluate pesticide/variety combinations for thrips infestation and damage in Kabete Field Station, University of Nairobi, Kenya. Four French bean varieties (Amy, Monel, Samantha and Impala) and four insecticides (Lambda-cyhalothrin (Karate 1.75 EC), Petroleum spray oil (DC Tron 500 ML), Spinosad (Tracer 480 SC) and Fipronil (Regent 50 SC)) were used for the study. The study revealed that both the varieties and insecticides influenced thrips infestation independently. Tracer 480 SC and Regent 50 SC gave the lowest thrips numbers in all the varieties. The mean number of F. occidentalis in Karate 1.75 EC sprayed plots was higher and significantly different from plots sprayed with Tracer 480 SC and Regent 50 Sc. The mean number of M. sjostedti was not significantly different for all the plots sprayed with Tracer 480 SC, Regent 50 SC and Karate 1.75 EC. DC Tron 500 ML had no significant effect on thrips infestation.

Narla, RD;, Muiru WM;, Olubayo FO;, Kimenju JW;, Kagiki MN;.  2007.  Efficacy Of Glyphosate 360sl On Weed Species Common In Vegetable Gardens With Different Types Of Weed Species.
M., DROLUBAYOFLORENCE.  2007.  A. W. Mwango. Plant Pathology journal 6 (2): 141-146.2007.. : Dr. Oliver V. Wasonga Abstract
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study was conducted in two seasons of2002 at Tigoni, Central Kenya to determine effectiveness of insecticides; neern  extract and mineral oil in managing potato aphids and their associated virus diseases. The treatments were arranged in  randomized complete block design (RCBD) with four replications. In each season, the number of aphids in five randomly  selected plants per treatment was recordced in situ. Virus symptoms (i.ncidence) were scored and expressed as a percentage  to the total plant population per plot. Forty-five days after emergence, 10 plants each from guard rows and inner rows were  randomly selected and serologically assayed for Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV) using DAS ELISA test. Results showd that three aphid species Aphis gossypii (Glover), Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) colonized on the variety with A. gossypii being the most dominant while M. persicae was least.  Higher aphid population coincided with the short rains experienced in one of the seasons. Synthetic insecticides (Bifethrin  and dimethoate) were the most effective among the treatments in reducing aphid infestation while the neem extract and mineral oil (DC- Tron) had no significant (P<0.05) difference. However, mineral-oil treated plots recorded the lowest PVY  incidence while bifenthrin-Ireated plots had the lowest PLRV incidence. It is suggested that a combination of synthetic  insecticides and mineral oil could playa major role in reduction of the aphids and their associated vectors. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

UoN Websites Search