Incidence Of Aphids Research Articles

POPULATION FLUCTUATION OF SUCKING INSECTS IN IRRIGATED AND NON-IRRIGATED COTTON CROPS

In the cotton crop (Gossypium hirsutum L.), there is a complexity of pests that appear systematically, thus significantly reducing crop yield; and their population fluctuation is strongly influenced by meteorological conditions that result in a greater or lesser density of these insects. Thus, this work aimed to evaluate the population fluctuation of insect pests with sucking feeding behavior in an area with and without irrigation in the cotton plant under second-harvest conditions. The experiment was developed at the State University of Maringá - Campus of Umuarama. In the experimental area, grid meshes of 10 × 10 m were demarcated, forming plots of 100 m², resulting in a total of 64 points in the irrigated area and 42 points in the non-irrigated area. The sampling points were demarcated in the center of each grid where three randomly selected plants were sampled. Samplings were carried out weekly, from 37 to 122 days after the emergence (DAE) of cotton, examining the aerial part of the plant, to observe the presence of aphids (Aphis gossypii), thrips (Frankliniella schultzei), and whitefly (Bemisia tabaci). The non-irrigated area provided the highest population peaks of whiteflies and thrips. On the other hand, the irrigated area had a higher incidence of aphids. However, with the increase in the population of ladybugs, the incidence of pests reduced significantly, showing the efficiency and importance of the control carried out by natural predators.

Influence of Weather, Vector and Variety on Incidence of Yellow Leaf Disease in Sugarcane

Yellow leaf disease of sugarcane (Saccharum spp.) caused by the Sugarcane yellow leaf virus (SCYLV), vectored by aphids has attained epidemic proportions causing severe yield losses, ranging from 20 to 40 % in susceptible varieties. Yellow leaf spread by aphids depends on cultivar susceptibility as well as weather parameters and thus the present studies were conceptualized. The observations on meteorological parameters were taken from the observatory at the station. The data on incidence of vector(aphids) and yellow leaf disease were recorded at weekly interval during the entire crop growth period on three sugarcane varieties viz., 2005 A 128, 2001 A 63 and 2003 V 46. The data on vector and disease incidence was correlated with weather parameters. The aphid incidence on 2005 A 128 initiated (4.6 per leaf) at 30 SMW and gradually increased to 19.1 per leaf at 40 SMW. In the variety 2001 A 63, the aphid incidence was first observed (2.2 per leaf) at 27 SMW and reached the peak population of 19.1 per leaf at 38 SMW. The aphid incidence on 2003 V 46 initiated (2.1 per leaf) at 29 SMW and gradually increased to 18.1 per leaf at 42 SMW. With regard to yellow leaf disease the incidence was first observed (1.0 per cent) at 26 SMW and reached the peak (28.7 per cent) at 37 SMW in the variety 2005 A 128. In the variety 2001 A 63, the incidence of yellow leaf disease was 1.8 per cent at 26 SMW which later on increased up to 29.4 per cent by 46 SMW. The incidence of yellow leaf disease was 3.5 per cent at 28 SMW which later on increased up to 27.6 per cent by 44 SMW in the variety 2003 V 46.The observations on incidence of aphids and YLD in susceptible varieties revealed that aphids contribute significantly to the initial spread of YLD, from initial incidence of aphids and YLD in 29-30 SW up to 42-44 SMW when the aphids reach peak incidence and YLD also leaps to above 25 per cent. The aphid population exhibited positive correlation with maximum temperature (r2=0.62), minimum temperature (r2=0.55) and relative humidity I (r2=0.65), whereas, negative correlation with rainfall (r2=-0.63). The yellow leaf disease exhibited positive correlation with minimum temperature (r2=0.75) and relative humidity I (r2=0.67), whereas, negative correlation with rainfall (r2=-0.63). The leaf and aphid samples were collected at peak incidence of Yellow leaf disease and were tested and found positive for presence of virus using ELISA reader at 405 nm.

Documentation of different pests and their natural enemies on tomato

Tomato (Solanum lycopersicum L.) is one of the most popular and widely grown vegetable crop of both tropicsand subtropics of the world. Itis a member of the family Solanaceae. Low tomato yields have been ascribed to a variety ofissues, including poor seed quality, pest infestations and severe weather conditions. The field study conducted in MainAgriculture Research Station, Dharwad revealed that, there are totally 8 species of pests, 3 species of coccinellids and 10different species of spiders were recorded in tomato ecosystem. The peak incidence of aphid, leafhopper, whitefly, thripsand mites was observed during last week of January, second week of January, first week of March, last week of Februaryand third week of February, respectively. The peak incidence of leaf miner, fruit borer and pinworm was observed duringlast week of February, second week of March and third week of February, respectively. Correlation coefficient betweendifferent weather parameters and population of tomato pests revealed that, maximum temperature recorded significantpositive correlation with population of whitefly, thrips, mites, leafminer, fruit borer and pinworm but negatively correlatedwith aphid and leafhopper.

Predicting the incidence and severity of wheat aphids and development of a web-enabled forewarning system in India

Aim: Forecasting the incidence and severity of aphids, the major insect pest of wheat, is expected to significantly help in their management. In the present study, a set of weather-based models were developed to predict the timing and severity of Rhopalosiphum maidis infestation at Ludhiana falling under the North Western Plain Zone and R. padi at Niphad in the Peninsular Zone of India. Methodology: The weather indices-based regression models for two locations, Ludhiana and Niphad, were developed using the aphid population and weather data gathered over eight years (2006–14), and the models' predictive accuracy was successfully tested over four additional years (2014-18). The developed statistical models were transformed into three-tier architecture, web-based system, i.e. Presentation, application and data tier for dissemination of information. Results: The developed models can predict the crop’s age - when aphids first colonize the plants, when the aphid population attains the peak and the information about the peak intensity of the aphid population. For predicting the crop’s age at which population peaked at Ludhiana, the weighted interaction of the relative humidity (RH) in the evening and the number of hours of sunshine (NHS) along with the weighted interaction of minimum temperature and RH (morning) were important parameters while, at Niphad, the weighted NHS and the interaction of RH (morning and evening) were important. Likewise, for predicting the maximum aphid population at Ludhiana, the weighted interaction of minimum temperature and RH (morning) were important, while at Niphad, the key parameters were the weighted interaction of RH (evening) with the NHS. Interpretation: A prototype system developed to forecast the location-specific (Ludhiana and Niphad) infestation of wheat crops by aphids is expected to facilitate aphid management through an accurate forewarning at the locations.

Increasing crop diversification and its impact on incidence of cabbage aphid in cruciferous vegetable ecosystem in Leh, Ladakh

Increasing crop diversification and its impact on incidence of cabbage aphid in cruciferous vegetable ecosystem in Leh, Ladakh

Evaluation of insecticidal efficacy against maize leaf aphid [Rhopalosiphum maidis (Fitch)] under inner terai condition of Nepal

Field experiments were carried out at the National Maize Research Program in Rampur, Chitwan, with the objective of comparing the effectiveness of insecticides in the field for controlling maize leaf aphid (Rhopalosiphum maidis Fitch) during the winter season of 2019 and 2020. The design of the experiment was randomized complete block with four replications. The plot size was 6 rows of 5 m long with the spacing of 60cm × 25cm. Maize hybrid Rampur Hybrid-14 (RML-86/RML-96) was used as experimental variety. The efficacies of five insecticides viz., thiomethoxam 25% w/w 0.2g/L (T1), acetamiprid 20%WP 2g/L (T2), flonicamid 50% WG 0.5g/L (T3), neemix 3ml/L(T4), imidacloprid 0.5ml/L(T5) and untreated control (T6) were used as experimental treatments. The recommended dose of fertilizer was 180: 60: 40 N: P2O5: K2O kg/ ha with farm yard manure 10 t/ha and seed rate was 20kg/ha. Data on aphid incidence, severity, yield and yield components were recorded. All the tested insecticides significantly (P≤0.05) reduced the plant infestation caused by maize aphid, and thereafter increased the grain yield of maize compared to control. However, newer insecticide flonicamid 50% WG 0.5g/L was found as the most effective insecticide with lower aphid colony per plant (2.85), aphid score (2.63), aphid infested plant (7.33%) and higher crop yield (7904.79kg/ha). The application of insecticides prior to their severe infestations is necessary for the efficient control of the maize leaf aphid. The research findings will assist maize farmers in choosing and applying the best insecticide to ensure efficient management of maize leaf aphid with high yield.

Incidence of Aphid on Different Brinjal Germplasm Related to Abiotic and Biotic Factors

The study was conducted with BD-7320, BD-7328, BD-9952, BD-10154, BD- 10158, BARI Begun-1, BARIBegun-4, BARIBegun-5, BARIBegun-6, BARIBegun-7, BARIBegun-8 and BARIBegun-9 germplasms of brinjal with a view to understanding the effect of temperature, relative humidity, rainfall and predators on the incidence of aphid during September 2018 to March 2019. Aphid incidence and infestation started from the last week of November and the highest incidence was recorded during 2nd week of January on BD-10154.At that week, aphid showed lower number of incidence on BARI Begun-5, BARI Begun-6, BARI Begun-8 and BARI Begun-9. The highest infestation of aphid was observed on BARI Begun-5 during 2nd week of March, when the lowest infestation was found on BD-9952. Maximum and minimum temperatures showed significant positive correlation, relative humidity (RH) and rainfall revealed non-significant correlation with aphid incidence. Aphid abundance showed highly significant positive correlation with the abundance of predators on all the tested germplasms.
 Bangladesh J. Agril. Res. 45(4): 371-378, December 2020

Population density of aphids in chrysanthemums grown under photoselective screens

The chrysanthemum is one of the main ornamental species in the world. It has great relevance in the market. Aphids are the main pests that affect the chrysanthemum crop and cause various types of damage to this plant. The objective of this study was to evaluate the influence of different cropping systems using photoselective screens on the population density of aphids in cut chrysanthemum. The study was carried out in an experimental area of the Federal Institute of Espírito Santo – Campus Itapina (Brazil) in a randomized complete block design, according to the split-plot scheme over time. The experiment was established in 3 blocks of 12 m in length with plots of 3 m containing different photoselective screens (red, silver, and black) and the control treatment (open field). Repeated evaluations at different times were done at 0, 15, 30, 45, and 60 d. Data were checked for normality and homoscedasticity and submitted to the Tukey’s test (P<0.05) and a non-parametric method of smoothing a dispersion graph with local weight (LOESS regression). Regardless of the color of the photoselective screen, there was a lower incidence of aphids compared to the open field treatment in the chrysanthemum culture with an average reduction of 84%. For the different sampling times, the Tukey test did not show significant differences between the means of aphid incidence in the evaluated period. Black, red, and silver photoselective screens promoted significant reductions in aphid populations in chrysanthemums of the variety Zembla in the environmental conditions of southeastern Brazil.

Impact of fertilizers and irrigation interval as well as methods on incidence of aphid and whitefly in Bt cotton

Impact of fertilizers and irrigation interval as well as methods on incidence of aphid and whitefly in Bt cotton

Population Dynamics of Aphid, Aphis gossypii Glover on Bt and non-Bt Cotton and Correlation with weather Parameters

Investigations on the population dynamics of aphid Aphis gossypii Glover on Bt (G.Cot.Hy.8 BG II) and non-Bt (G.Cot.Hy.8) were carried out at Main Cotton Research Station, Navsari Agricultural University, Surat, Gujarat during the Kharif, 2020-21. The incidence of aphids initiated in the first week of July (27th SW) in Bt cotton hybrid and in the second week of July (28th SW) in non-Bt cotton hybrid and continued till the crop harvest in the second week of January (2nd SW) in both the hybrids. The peak activity of aphids was recorded during the third week of December (51st SW) in Bt as well as non-Bt cotton hybrid. In both Bt and non-Bt cotton, the aphid population had a significant negative correlation with morning relative humidity. There was a highly significant negative correlation with minimum temperature, evening relative humidity, rainfall, rainy days, and a positive correlation with sunshine hours.

Efficacy of Sulfoxaflor 12%SC Against Aphids Complex and <i>Coccinella septempunctata</i> L. in Wheat

Efficacy of dosages of sulfoxaflor 12%SC were evaluated for the control of foliar aphids under Contract Research Project on wheat during rabi seasons of 2014-15 and 2015-16 at the research farm of ICAR- Indian Institute of Wheat and Barley Research, Karnal, Haryana. The standard check insecticides thiamethoxam 25WDG and quinalphos 25EC were included along with sulfoxaflor, and all the treatments were found to be significantly superior. The incidence of aphids/ shoot/ plant was significantly less with sulfoxaflor 12 SC @ 24, 27 and 30 g a.i./ ha with 94.54, 95.27 and 96.03% reduction, respectively; these being at par with each other, followed by thiamethoxam 25WDG @ 12.5 g a.i./ ha and quinalphos 25EC @ 250 g a.i./ ha. The seven-spotted ladybird beetle Coccinella septempunctata L. was the main natural enemy observed in the crop, and its counts were the least (1.50/ m2) with thiamethoxam 25WDG @ 12.5 g a.i./ha at 14 DAS. The pooled data revealed that the yield was significantly more with sulfoxaflor 12SC @ 24, 27 and 30 g a.i./ ha (52.21, 52.62 and 54.32 q/ ha) followed by thiamethoxam 25WDG @ 12.5 g a.i./ ha (49.87 q/ ha) which was at par with quinalphos 25EC @ 250 g a.i./ ha (47.73 q/ha). Considering incremental cost benefit ratio, sulfoxaflor 12% SC @30 g a.i/ ha (1:2.70) is the most economical, and no phytotoxicity symptoms were observed at its doses @30 and 60 g a.i/ ha.

Evaluation of Coriander Genotypes for Resistance to Coriander Aphid <i>Hyadaphis coriandri</i> (Das)

Twelve genotypes of coriander were evaluated against coriander aphid Hyadaphis coriandri (Das) during 2015-16 and 2016-17. The genotypes viz., RCr-435, RCr-436, RCr-446 and RCr-684 were categorized as least susceptible; RCr-475, RCr-480, RCr-728 and UD-856 as moderately susceptible; RCr-20, RCr-41, UD-857 and Local as highly susceptible. The days taken for 50% flowering, plant height and days to maturity positively influence the aphid incidence, whereas, umbels/plant and seeds/umbel influence it in a non-significant manner. The biochemical constituents viz., total phenol and volatile oil exhibit non-significant correlation with aphid incidence.

Effect of a cover crop on the aphid incidence is not explained by increased top-down regulation.

BackgroundCover crops can be used as a habitat management strategy to enhance the natural enemies and their temporal synchronization with a target pest. We examined the effect of winter oat intercropping within organic plum orchards on the natural enemy abundance and seasonal dynamics on the biological control of plum aphids in spring in Central Chile.MethodsWe compared the incidence and abundance of natural enemies and aphid pests from winter to the end of spring using two treatments: (1) plum trees with an oat cover crop (OCC) and (2) plum trees without a cover crop but with spontaneous vegetation (SV). We hypothesized that cover crops allow the development of winter cereal aphids, promoting the early arrival of natural enemies in spring, resulting in an earlier control of plum aphids.ResultsWinter cereal aphids developed well on the OCC, and as a result, a lower plum aphid incidence in spring was observed when compared to the SV. However, the abundance of natural enemies and the parasitism rates cannot explain the positive impacts of the oat cover crop on the aphid populations as there were no differences between treatments. A potential effect of the oat due to chemical and/or physical stimuli (bottom-up effects) could help to explain these results.

Screening of Maize Genotypes against Maize Leaf Aphid [Rhopalosiphum maidis (Fitch)] under Field Condition at Chitwan, Nepal

Thirty maize genotypes including five hybrids, eight quality protein (QPM) and seventeen full season open pollinated (OP) were screened for their resistance against maize leaf aphid (Rhopalosiphum maidis Fitch) at the research field of National Maize Research Program, Rampur, Chitwan, Nepal during the year 2019 and 2020. The design of the experiment was randomized incomplete block with three replications. The plot size was 2 rows of 5 m long with the spacing of 60 cm × 25 cm. The recommended dose of fertilizer for full season OP and QPM were 120:60:40 and for hybrid maize 180:60:40 N: P2O5:K2O kg/ha with farmyard manure 10 t/ha and seed rate was 20 kg/ha. Data on aphid incidence, severity, yield and yield components were recorded. Maize hybrids RML-95/RML-96 (18%) and Rampur Hybrid-10 (22%), two quality protein maize (QPM) S00TLYQ-AB (22%) and S99TLYQ-A (23%) and two full season OP genotypes TLBRS07F16 (24%) and ZM 627 (26%) were less susceptible to aphid infestation and resulted in higher grain yield. The findings could aid in the selection of maize genotypes for the development of aphid resistant and high-yielding maize varieties.

Effect of Different Nethouses on the Incidence of Insect on Vegetable Crops

In this study, the effects of different types of nethouses viz., NH1, NH2, and NH3, were investigated at the research farm of the Olericulture Division, Bangladesh Agricultural Research Institute (BARI) from Sep 2021 to Mar 2022 and compared to control (open field) in terms of the incidence of white fly, aphid, leaf miners, mites, and eggplant shoot and fruit borer (ESFB). This study included six vegetables 1) Tomato, 2) Eggplant, 3) Sweet pepper, 4) Broccoli, 5) Cucumber; 6) Okra, as well as four nethouse treatments: 1) UV stabilized transparent polyethylene film with 60 mesh insect net along with green shade net (NH1); 2) UV stabilized transparent polyethylene film with 60 mesh insect net (NH2); 3) 60 mesh insect net (NH3); 4) Open field infestation of white fly, aphid, leaf miners, mites, and ESFB was observed under open field conditions followed by NH1 conditions, while the lower infestation was observed in NH2 and NH3 for all vegetables. From the study, we found the use of stabilized transparent polyethylene film with a 60 mesh insect nethouse provided a negative effect on the presence of different types of notorious insects on vegetables. So, this type of protected nethouse will provide a new dimension to producing safe and quality vegetables in Bangladesh.

Providing Alternative Hosts and Nectar to Aphid Parasitoids in a Plum Orchard to Determine Resource Complementarity and Distance Range Effect on Biological Control

There are many different practices that contribute to conservation biological control, but little is known about their complementarity. We tested the effects of providing food and alternative hosts to parasitoids by intercropping a plum orchard with companion plants. Oats and vetch were intercropped into the orchard either as single-species (oats or vetch) or two-species (oats and vetch combined) intercrops within an inter-row. The trophic resources provided by these intercrops were assessed, along with the incidences of aphids and their parasitoids in plum trees. We found up to ten alternative host species provided by oats and vetch, and extrafloral nectar was available from the vetch and mixed strips. An effect of intercrop type and distance to plum trees was observed on aphid incidence during one sampling period. Parasitism rates in exclusion cages were affected by intercrop type, reaching almost 60% close to the mixed intercrop. However, no general tendency was observed upon whether oats, vetch or their mixture was associated with a lower incidence of aphids. We found no evidence that providing effective sources of food and alternative hosts for parasitoids increased aphid mortality in this study. The context-dependent efficiency of intercropping is discussed.

Biological effectiveness of quillay (Quillaja saponaria) extracts for the control of yellow aphids (Melanaphis sacchari) in sorghum

Objective: To evaluate and define a plant extract for the control of the yellow aphid in order to prevent environmental contamination and improve crop profitability. Design/Methodology/Approach: In a sorghum plot —located in the municipality of Jantetelco, Morelos— with a high incidence of yellow aphids, three doses —2-, 4-, and 6-mL L-1 of water of Quillaja saponaria extract, 0.2-mL L-1 of water of Imidacloprid, and 10-mL L-1 of water of calcium polysulfide—, as well as an absolute control, were evaluated. The applications were carried out using a 15-L manual spray backpack, which had been previously calibrated and had a fan nozzle. A randomized block experimental design—with six treatments and four repetitions— was used. The experimental unit was made up of five 5-m long rows with 0.70 m between rows, resulting in a 17.5 m2 total area per experimental unit. The three central furrows were the useful plot, leaving 0.5 m at each end of the furrow. The total size of the experimental plot was 420 m2. Results: The biological effectiveness during the samplings was as follows: both the Quillaja saponaria (6-, 4- and 2-mL L-1 water doses) and Imidacloprid treatments had a 100% effectiveness. Study limitations/implications: This study was carried out in sorghum crops. Findings/conclusions: Treatments based on Quillaja saponaria extracts on M. sacchari in sorghum crops showed 100% biological effectiveness from the first application and no phytotoxicity was observed in any treatment

Influence of Abiotic Factors on Population of Aphid Complex and Its Coexisting Natural Enemies in Mustard Agroecosystem

A field experiment was conducted to determine the population build-up of mustard aphid and their natural enemies in relation to abiotic factors at TCA, Dholi during the Rabi season of 2018-19 and 2019-20 respectively. The incidence of mustard aphid started in the 2nd and 3rd SMW of 2019 and 2020 respectively and reached maximum in 8th SMW in both the years. However, the predatory activity of coccinellids, syrphid larvae and spiders were started from 3rd SW with their peak activity at 3rd and 4th week of February in both the years. Mustard aphid population exhibited positive correlation with maximum temperature (0.347 & 0.543), minimum temperature (0.317 & 0.152) and negative correlation with relative humidity (-0.083 & -0.479) during 2019 & 2020 respectively and rainfall (-0.35) during 2020. However, natural enemies viz., coccinellids, syrphid larvae and spiders exhibited positive correlation with Tmax, Tmin, rainfall and negative correlation with RH in both the years.

Efficacy of Insecticides Against Mustard Aphid Brevicoryne brassicae and their Safety to Coccinellid Predators

Field experiment was conducted during rabi 2018-19 to ascertain the efficacy of insecticides on mustard aphid Brevicoryne brassicae L., and their safety to the coccinellid predators. Insecticides viz., imidacloprid17.8SL (0.30 ml/l of water), dimethoate 30EC (1 ml/l of water), cypermethrin 10EC (0.6 ml/l of water), chlorpyriphos 50EC+ cypermethrin 5EC (1ml/l of water), profenophos 40EC+ cypermethrin 4EC (1ml/l of water), neem oil (2ml/l of water), dichlorvos 76 EC (1ml/l of water), chlorpyriphos 20SC (0.5 ml/l of water) were evaluated. Profenophos 40EC+ cypermethrin 4EC was found to be the most effective in reducing the aphid incidence. Neem oil and imidacloprid proved to be safe to the coccinellid predators viz., Coccinella septumpunctata (L.) and Hippodamia variegata (Goeze); while profenophos + cypermethrin was found to be the most toxic. Thus, imidacloprid can be used for the management of B. brassicae as it is the most effective and also safe to coccinellid predators.

Evaluation of Bean Common Mosaic Disease and Associated Aphid Vector, Aphis fabae L., on Common Bean (Phaseolus vulgaris L.) Production in Lower Eastern Kenya

Production of common bean in Kenya is constrained by pests and diseases and to improve bean yields amongst majority small-scale farmers, appropriate management strategies should be adopted. Bean common mosaic disease (BCMD) caused by bean common mosaic virus and vectored by bean aphids and infected seeds, substantially inhibit common bean production in Kenya. An extensive and diagnostic field survey was conducted in six agro ecological zones (AEZs) of lower eastern Kenya during the long and short rains of 2018 to determine BCMD incidence (BCMD-I), severity (BCMD-S), bean aphid abundance (BAA), bean aphid incidence (BAI) and the management strategies applied by farmers. Significant (P≤0.001) variations observed for these traits between bean varieties, rainy seasons and AEZs implied that farmers could select and grow a tolerant bean variety or grow a variety either in a season or an AEZ with low BCMD and bean aphid pressure. Such included AEZ-UMSA with least mean BCMD-I (42%), BCMD-S (1.9) and BAI (11%) compared to two AEZs (LHSH & LM4) that showed BCMD-I of >70%, BCMD-S >3.0 and BAI >50%. The AEZs differences could be attributed to variations in altitudes, temperature and humidity that influences vector (aphid) movement. Of the nine bean varieties identified during the survey, Selian 14 was the most preferred by farmers (at ~35%) with relatively lower BCMD-I (~49%) and BAI (~35%) compared to the least (<5%) farmer-preferred variety Wairimu that showed higher BCMD-I (56%) and BAI (~68%). Therefore variety Selian 14 was considered tolerant to BCMD and bean aphid. Significant (P≤0.001) and positive correlations (r = 0.67) between BAI and BCMD-I implied an effective control of bean aphids could reduce the impact of BCMD on bean production. On visual diagnostics, >75% of farmers could generally identify diseased or pest-infested bean crops and stage of growth of the crop most affected. None (0%) could however identify BCMD symptoms although ~40% identified the vector bean aphids with ~26% implementing some form of aphid or pest management strategy. On management, season-driven early planting and bean intercropping were the most applied strategies (>80%), crop rotation and weed control accounted for ~71%, certified seeds at 1% and non-chemical or pesticide applications (0%). Both low adoption of certified seeds and no chemical aphid control were attributed to high costs, despite the possibility the two factors could have contributed to higher incidences and severity of BCMD in the study area as the disease is both seed and vector-borne. In summary, lack of knowledge and training among farmers on diagnosis and management of aphid-pests and BCMD, were cited as the main constraints for low bean cultivation. This study therefore recommends provision of adequate extension services and farmer training in lower eastern Kenya for improved bean yield and subsequent better family livelihoods and income.