Agronomy

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The Fate of Afiatoxins During Processing of Maize into Muthokoi - A Traditional Kenyan Food
(ScienceDirect, 2008-07) Mutungi Christopher; Lamuka Peter; Arimi Samuel; Gathumbi James; Onyango Calvin
The effect of processing muthokoi, (a traditional dehulled maize dish in Kenya) on aflatoxin content of naturally contaminated maize was investigated. Dehulling decreased aflatoxin levels by 46.6% (5.5-70%) in maize samples containing 10.7-270 ngjg aflatoxin levels. Soaking muthokoi in 0.2%, 0.5% and 1.0% solutions iati, sodium hypochlorite or ammonium persulphate for 6 or 14 h further decreased aflatoxin contents by 28-72% in maize samples containing 107-363 ng/g aflatoxin levels, and boiling muthokoi at 98°C for 150 min in 0.2-1.0% w/v iati decreased aflatoxin contents by 80-93% in samples having 101 ng/g aflatoxin contamination. Findings imply that expo¬sure to acute aflatoxin levels in maize is minimised during processing and preparation of muthokoi.
Survival and Avoidance Response of the Freshwater Gastropod Melanoides Tuberculatus (Muller) to Different Concentrations of Tobacco Waste.
(Wiley online library, 2011-11) Ochieng Eric; Omondi Reuben; Opiyo Mary A.; Charo-karisa Harrison; Muguti Jonathan; Aura christopher Mulanda
The Gastropod Melanoides tuberculatus plays a significant role in hampering fish larval production in earthen ponds. This study investigated use of tobacco waste to assess behavioural and survival responses of M. tuberculatus at different concentrations of tobacco waste solution of 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 1.75 and 2 g L−1. Mean escape time varied significantly among concentrations (P < 0.05). Escape time decreased in 1-, 2- and 3-day-old solutions. Percentage survival decreased significantly with increasing concentrations of tobacco waste solution and exposure time (P < 0.05). Concentrations of 1.75 g L −1 and 2.0 g L−1 had high hazard ratios and low survival rates of gastropods and were the most effective in eradication of M. tuberculatus, hence recommended dose for preparing ponds for stocking. We conclude that tobacco waste solution can be used for control of M. tuberculatus.
Improving crop productivity and water use efficiency in basin rice cultivation in Kenya through SRI
(International Journal of Agricultural Science Research., 2012-05-23) Nyamai, Matolo; Mati, Bancy Mburia; Home, Patrick Gathogo; Odongo, Benson; Wanjogu, Raphael; Thuranira, Elias
Improving the yield of rice (Oryza sativa L) in existing irrigated areas rather than further expansion is more likely to be the main source of growth for the crop in Kenya, especially due to limited land and water resources. In order to achieve this, there is need to identify and adopt solutions that are environmentally more sustainable. That is, the production systems adopted should reduce water consumption and increase productivity. This study evaluated whether the System of Rice Intensification (SRI) could increase water use efficiency and crop productivity relative to the conventional production system of continuous flooding. The effects of SRI on total water input and the growth characteristics of three rice varieties were investigated in a split-plot factorial at the experimental farm of the Mwea Irrigation Scheme of Kenya during the August - December 2009 growing season on vertic clay soils. The production practices of SRI were found to be beneficial to rice growth. SRI gave higher average grain yield (14.85 t/ha) than the conventional production system (8.66 t/ha) at P=0.006, while the average yield across production systems was 15.89 t/ha, 11.26 t/ha and 8.10 t/ha for BW196, NERICA1 and Basmati370 varieties respectively, with P
The impact of Desmodium spp. and cutting regimes on the agronomic and economic performance of Desmodium–maize intercropping system in western Kenya
(Elsevier, 2012-10-20) Kifuko-Koech, M.; Pypers, P.; Okalebo, J. R.; Othieno, C. O.; Khan, Z. R.; Pickett, J. A.; Kipkoech, A. K.; Vanlauwe, B.
Low soil fertility, stemborers (particularly, Chilo partellus) and Striga weeds (Striga hermonthica and Striga asiatica) are major limitations to production of maize in western Kenya. The “Push–Pull” technology (“PPT”) has been described as an appropriate innovative technology capable of addressing these constraints. The technology involves intercropping maize with Desmodium and planting Napier grass (Pennisetum purpureum) around the intercrop, but in the current study a modified PPT was used and Napier grass was not included. Field trials were conducted in two locations in western Kenya during 4 subsequent seasons to test the hypothesis that maize yield, the degree of Striga suppression and economic benefits of intercropping maize with Desmodium are affected by: (i) the related biomass production by different Desmodium species and (ii) the cutting regime of the Desmodium. Maize was intercropped with Desmodium uncinatum (Jacq.) DC, cv Silverleaf or Desmodium intortum (Mill.) Urb. cv Greenleaf, and treatments with sole maize (with and without urea) were included for comparison. To eliminate phosphorus (P) deficiency, all treatments received basal P. The first two Desmodium cutting events were fixed at land preparation i.e. at the start of every season, and 4 weeks later, following the recommended practice, while the third cutting was varied and conducted at 9, 12 or 18 weeks after planting maize. Maize yield in the Desmodium–maize intercropping system was only higher than sole maize without urea from the third season. This implies that when P is not limiting inclusion of Desmodium spp. into the maize cropping system would provide a substitute for inorganic N fertilizers to enhance crop growth and yield after Desmodium becomes well established. Cumulative maize grain yield over the four seasons with the D. intortum and D. uncinatum intercrops were 6.3 and 7.0, and 10.9 and 11.6tha−1 in Busia and Siaya, respectively, and significantly higher than or comparable to a maize monocrop (5.8 and 11.8tha−1). Average net benefits from Desmodium intercropping over the four seasons were increased by 1290 and 918$ha−1 relative to the maize monocrop in Busia and Siaya, respectively. Biomass yields were significantly higher for D. intortum than for D. uncinatum. Varying the time of the third Desmodium cutting had little effect on Desmodium biomass yields or maize grain yields in Busia, while in Siaya, D. intortum biomass yields were highest when cut at 12 weeks after planting. In the Desmodium intercropping systems, Striga counts were reduced by 95% in Busia and by 65–90% in Siaya with higher reductions when Desmodium was cut at 18 weeks after planting. In summary, the use of PPT provides robust and high economic benefits to smallholder farmers in western Kenya. The use of D. uncinatum with the third cutting at 18 weeks after planting is recommended, but can be modified according to the need for fodder without much effect on maize yield or revenue.
Adoption, constraints and economic returns of paddy rice under the system of rice intensification in Mwea, Kenya
(Elsevier, 2013-11-01) Ndiiri, J. A.; Mati, B. M.; Home, P. G.; Odongo, B.; Uphoff, N.
A detailed farm survey was conducted in Mwea Irrigation Scheme, Kenya during the 2010/2011 and 2011/2012 main growing seasons to assess the adoption and to quantify the net income advantages of using system of rice intensification (SRI) management over farmer practices (FP) for rice cultivation. Data were collected through questionnaires and structured interviews with farmers who were practicing both SRI and FP methods of rice production on their farms. Under FP, three seedlings aged 28 days are transplanted in respective hills at random spacing. The fields are then flooded with water throughout the growing period. For SRI practice, factors considered as essential were transplanting only one seedling per hill aged 8–15 days with spacing of at least 20cm by 20cm; weeding the crop at least three times at intervals of ten days; and intermittently irrigating the fields. The contributions of using organic manure for fertilization and soil-aeration weed control methods were not considerations in this study since the availability of organic materials and mechanical push-weeders were challenges at the time of study. A total of 40 farmers in 10 units out of the 50 SRI farmers from 18 units of the irrigation scheme were sampled. Benefit–cost relationships were estimated using tabular analysis of all the variable costs and income from production using the survey data. On average, yield under SRI management increased by 1.6t/ha (33%), with seed requirements reduced by 87% and, water savings of 28%. SRI required 9% more labor than FP on average, but this factor of production showed great variability; in three Mwea units, labor costs were reduced by an average of 13%. SRI required 30% more labor for weeding than FP in the first season, but this was reduced to 15% in the second season when push-weeders became available. The results showed SRI giving a higher benefit–cost ratio of 1.76 and 1.88 in the first and second seasons, respectively, compared to 1.3 and 1.35 for FP. The results indicated that SRI practices of planting younger seedlings, with wider spacing and intermittent irrigation, lead to increased paddy rice yields with concomitant rise in the income accruing to farmers. Possibly further increases in net benefit could come with enhanced availability of mechanical weeders and using organic material for fertilization. Up-scaling of SRI in Mwea can be expected to help achieve greater national and household food security
Relationship between Level of Participation of Researchers, Extension Agents and Farmers in On-Farm Research Trials and Adoption of Technologies Case Study: Maize and Beans Producers, Kenya
(Institute of Development Studies, 2014) Ochola W.A.; Basweti E.A.; Ogendi G.M.; Onyango C.A.; Ochola W.O.
This study was conducted to determine the relationship between level of participation of researchers, extension agents and farmers in on-farm research trial activities and level of adoption of technologies developed through that process. The study was based on technologies used to improve the productivity of maize and beans in southwest Kenya. The study used an ex-post facto research design with a survey methodology. It was designed to use three sets of questionnaires directly administered to farmers, extension agents and researchers to collect data from the researchers, farmers and government extension agents. Stratified random sampling technique was used to select 104 respondents. The study established that; there was a significant relationship between occupation of respondents and their level of participation; there was a significant difference between the level of involvement of farmers, extension agents and researchers with the mean participation of the extension agents being relatively high compared to the researchers and farmers in on-farm related activities. However, there was low level of interaction between the researchers, extension agents and farmers; and there was a significant relationship between agro-ecological zones (AEZs) and level of participation of farmers with farmers at higher AEZs having higher participation levels compared to the farmers at the lower zones. The study finally concluded that, there was a strong positive relationship between the level of participation and level of adoption. The study therefore recommends that extension agents and researchers should consider improving their level of participation in joint activities.
Recent Limnological Changes and Their Implication on Fisheries in Lake Baringo, Kenya.
(Academic Journals, 2014) Omondi R.; Kembenya E.; Nyamweya C.; Ouma H.; Machua S. K.; Ogari Z.
Water samples for physico-chemical analysis for this study were collected monthly for five years between April 2008 and March 2013. Conductivity, temperature, dissolved oxygen and pH was measured in situ using a Surveyor II model hydrolab. Chlorophyll-a concentration was determined using a Genesys 10S Vis spectrophotomer. Nutrients were determined using standard methods and procedures. Analysis of Variance (ANOVA) was used to determine spatial and temporal variation in physico-chemical and biological factors. Principal component analysis (PCA) was performed to establish the correlation of the physico-chemical and biological parameters among sampling stations and to group stations with similar physico-chemical parameters. Both spatial and temporal significant variations (P<0.05) were detected in the concentrations of the nutrients measured during the study.
Internal Transcribed Spacer Primers Detect Better Ustilago kamerunensis; A Napier Grass Head Smut Pathogen Constraining The Dairy Sector In Eastern Africa
(JAAS, 2014-09-30) Omayio, do; Ajanga, SI; Muoma, JV; MuyekhO, FN; Kariuki,I
Two completely randomized glasshouse screening experiments in design coupled with two molecular screening assays were carried out at Kenya Agricultural Research Institute’s Muguga South and Trypanosomiasis Research Centres both located at 2095m above sea level at the (1o 13’ 53.0” S) and (36o 38’ 1.1” E) of Kiambu County in Kenya. The aim of the studies was to determine the efficacy of four different primer pairs in the detection of Ustilago kamerunensis in selected asymptomatic (non-smutting) napier grass accessions’ tissues at expected PCR band sizes and to investigate whether the selected accessions were completely resistant (immune) or tolerant to the pathogen. The glasshouse screening results revealed predominant differences in the smutting proportions of the accessions ranging from 0% to 90.22%. These differences were further manifested in the accession’s respective neighbour joining groups where a heterogeneous pattern in response to disease challenge was observed. The molecular screening assays demonstrated that internal transcribed spacer (1 / 4) primers were better in detecting the pathogen in the asymptomatic accessions’ tissues followed by β-tubulin (F1 / R2) primers at the expected band size. The molecular screening showed that ten out of eleven asymptomatic accessions and the four checks despite not smutting had the pathogen in their tissues with exception of accession 16806 which did not exhibit any in both molecular trials. The results indicated that the ten out of eleven selected asymptomatic accessions to head smut disease seemed tolerant and only 16806 seemed completely resistant (immune) to the napier head smut disease
Predicting Endophytes Contribution In vivo in Napier Grass Accessions’ tolerance against Ustilago kamerunensis Using In vitro Strategies
(JAAS, 2014-10-30) Omayio, DO; Ajanga, SI; Muoma JV; Ochieno, DMW; Muyekho, FN; Mukoye, B; Leitich,RK
Two completely randomized laboratory assays were carried out at the plant pathology section of the National Agricultural Research LaboratoriesKabete in Nairobi Kenya. The aim of the studies was to determine the abundance of endophytes among an initially selected and presumed tolerant napier grass accessions to head smut pathogen and to decipher their possible synergistic or individualistic contribution to the accessions asymptomatic response to the disease challenge. The analyzed Shannon diversity indices results indicated that the abundance of fungal endophytes was unequal with some exceptions. Moreover, low inhibition percentages were obtained of the morphotypes in dual cultures in vitro with the pathogen, besides most of their interactions favouring the luxurious growth of the pathogen. Therefore, direct role of the endophytes to the tolerance of the accessions seems nonexistent if not minimal. However, heightened hormonal secretions like auxins by the crop need to be investigated to determine whether the endophytes are enhancing its production to enable the plants tolerate the pathogen damage through compensatory growth strategies
Effect of Incorporating Lablab Biomass in Soils on Root Rot Disease Complex and Yield of Beans Intercropped with Maize
(International Journal of AgriScience, 2014-12) Muthomi J. W.; Mugambi, I. K.; Ojiem J.; Chemining’wa G. N.; Nderitu J. H.
Root rot is a major constraint to bean production in western Kenya causing poor crop stand and high yield losses. The disease is caused by a complex different pathogens which together exhibit synergistic effects. The pathogens survive in soils as resting spores and options of managing the disease are limited This study evaluated the effectiveness of incorporating lablab biomass in managing root rot of beans in maize intercrop system. The experimental treatments evaluated were incorporation of lablab biomass over the whole plot, biomass placed between rows of beans, biomass removed from the plot plus application of inorganic fertilizer and biomass removed from the plot without fertilizer application. In each experimental treatment, four bean varieties KK8, KK15, KK072 (tolerant to root rot) and GLP2 (susceptible to root rot) were planted intercropped with maize. The experiment was carried out at two agro-ecologically and soil fertility diverse sites. Incidence of root rot and chafer grub was determined at early growth stages while biomass and yield of both maize and beans were determined at harvest. Incorporation of lablab biomass increased soil carbon and nitrogen content but reduced both pH and cation exchange capacity. However, it reduced root rot incidence for the root tolerant bean varieties at the low soil fertility site but increased chafer grub incidence. Bean stem bases from the high soil fertility site had higher incidences of infection with Fusarium oxysporum while Fusarium solani and Macrophomina phaseolina were more prevalent in the low soil fertility site. Addition of lablab biomass significantly increased both bean biomass and seed yields in both low and high soil fertility sites. The positive effect on yield was more pronounced at the low soil fertility site. The study indicated that addition of lablab biomass to soils is beneficial in managing root rot of beans and improving crop yields in low soil fertility areas. The use of green manure soil amendments is an ecologically sustainable way of increasing bean yield for small scale farmers.
Using Napier grass accessions' origins, neighbour joining groups their responses to Ustilago kamerunensis to predict a probable evolutionary scenario
(IJRSR, 2015-02) Omayio, DO.; Ajanga, SI; Muoma, JV; Muyekho, FN.; Yamame, MK.; Kariuki, I; Mwendia, S
Prediction of a possible co-evolutionary process is critical in a plant-pathogen interactionbasing on a host plant’s origin, its molecular characteristics and involved pathogen’s history. Therefore, two successive screening experiments in completely randomized design were set up at Muguga-south glasshouses in Kenya. The study objective was to determine whether the resistant napier grass accessions exhibited any indications of selection preference to origin as may have been influenced by the African pathogen. Smutted tiller numbers and subsequentlyproportions of smutting among the accessions were determined to enable the within and across evaluation of the accessions’ neighbour joining groups. The accessions exhibited observable differences with 67.9% and 32.1% smutting and not smutting respectively. Further, on across evaluation of the respective groups; the Southern Africa neighbour joining group had the most asymptomatic accessions at 35.29% whereas the USA 1 and 2 had the least at 5.88%. Onwithin the groups’ evaluation, the Southern Africa and USA 2 had the highest and least relative resistance indices of 0.2900 and -1.2606 respectively. Whereas, for the relative susceptibility indices the USA 2 had the highest and Southern Africa group the least at 0.2940and -0.1732 respectively. The results suggest that resistance trait selection preference seems tobe skewed towards accessions whose origin is from Africa especially south of Africa where the grass traces its origin at the Zambezi valley.
The Utilization of Cassava (Manihot Esculenta) and Quality Characteristics of Improved Varieties. A Case of Marigat, Baringo County.
(University of Eldoret, 2015-05) Yabann Eunice
Cassava provides vital nutrients to its consumers and is considered a food security crop for poor rural communities, particularly in arid and semi-arid regions of developing countries. The nutritional value of this crop is normally affected by many factors. In the central Rift Valley of Kenya, scientists have introduced new varieties. However, little is known about utilization and quality characteristics of new varieties, thus the need for this study. The objective of this study was to evaluate the utilization of cassava roots among the study group and to study culinary characteristics and nutritional values of the newly introduced cassava root variety. A total of 51 introduced cassava varieties were grown and all harvested at 16 months of age by Kenya Agricultural Research Institute (KARI)-Marigat. External preference mapping resulted in sensory panelists rejecting some of the cassava roots (n = 26) from further processing owing to the fact that they were woody, rotten, dark colored and fibrous. The remaining samples (n = 25), plus one sample (n = 1) picked from the local market were prepared and evaluated to determine ease of cooking. The panelists evaluated each sample and recorded their opinion in terms of surface appearance, taste, texture and overall acceptability. The attributes were scored using a hedonic scale ranging from 1-5 (where 1 = worst and 5 = very good). The varieties with a mean score of three (m = 3.0) and above in the given attribute(s) were considered acceptable. The surface appearance scored the highest means (3.80 ± 0.63) and least mean score was texture (3.20 ± 0.42). ANOVA results showed a significant mean difference in their sensory characteristics. The final test eliminated some of the cassava samples (n = 16). The remaining accepted cassava samples (n = 10) were further processed for nutritional quality determination. Proximate composition and mineral elements were measured using AOAC and HPLC. The results obtained were compared with U.S.D.A-21 reference standards. Protein levels of cassava variety R252m recorded the highest with 2.05% per 100g lower than the 3% USDA-21 reference standards. Fats ranged from 0.17% to 1.24% with only P12m cassava sample having value above the reference standards (1%). Carbohydrate (CHO) values were high in POROs with the value of 93.51% per 100gm, higher than the recommended U.S.D.A 21 standards (78%). Calcium (Ca) recorded highest in the variety P15 at 6.92% per 100g while P117o had the highest Fe content with 1.56 % per 100g. Phosphorus (P) was found in large amounts with P15m leading with 96% per 100gm. Iron (Fe), Fat, Potassium (K), and Protein had significant positive correlation with sensory qualities.
Quality Evaluation of Oil from Seeds of Wild Plant Tylosema fassoglensis in Kenya
(Journal of Food Processing, 2015-07-15) Ojwang D. Otieno; Okewo B. Awuor; Wanjala G. Wafula
Tylosema fassoglensis is a plant species that is native to Sub-Saharan Africa. The aim of this study was to evaluate the physicochemical properties of oil from T. fassoglensis in Kenya. Seeds of T. fassoglensis were collected from Mombasa, Taita Taveta, Homa Bay, and Siaya regions. Counts of T. fassoglensis in each region were recorded during the entire survey period. The highest distribution was recorded in Homa Bay followed by Siaya region. Distribution was the least in Taita Taveta and Mombasa regions. The analysis of the physicochemical characteristics of the oil was performed according to the official methods of analysis and the recommended practices of the American Oil Chemists Society. Oil content of 36.4% was obtained. The oil had refractive index 1.47 at 40°C, peroxide value 6.34 meq O2/kg, iodine value 94.06 g of I2/100 g, saponification value 145.93 mg KOH/g of oil, acid value 2.49 ± 0.56 mg KOH/g of oil, and unsaponifiable matter 5.87 g/kg. The oil had Lovibond color index of 2.0Y+28.0R. Oil content of T. fassoglensis is comparable with those of most oil crop under commercial production. The physicochemical properties of oil from T. fassoglensis are within the range recommended by FAO/WHO and hence suitable for human consumption.
Productivity Gaps among Groundnut Farmers in Kenya and Uganda: A Stochastic Production Frontier Analysis
(African Journal of Agricultural and Resource Economics, 2016) Asekenye Cresenia; Bravo-Ureta Boris E; Deom Mike; Kidula Nelson; Okello David Kalule; Okoko, Nasambu; Puppala, Naveen
Productivity gaps for 321 groundnut farmers from Uganda and Kenya were analysed using data from the 2009 growing seasons. Farmers who planted improved varieties enjoyed output advantages of 143% in Uganda and 58.6% in Kenya over those who planted only local varieties. Farmers had a mean technical efficiency of 54.6% in Uganda and 54.4% in Kenya. No significant differences were found in the mean technical efficiencies of research and non-research farmers, and between maleand female-managed plots. Productivity therefore could be enhanced if highefficiency households invest more in improved varieties and if low-efficiency households make better use of their existing technology. Continued development of improved varieties will further shift the production frontier outward. The apparent spill-over effect of the technical support received by research and nonresearch farmers suggests that farmer education has a multiplier effect. An improvement in extension service delivery could help to enhance the managerial skills of both farmer categories.
Is Partial Root Zone Drying Irrigation A Feasible Water Saving Strategy In African Leafy Vegetable Production? A Review.
(Afr. J. Hort. Sci., 2016) Odula, Osia; Wesonga, John; Masinde, Peter; Stützel, Hartmut
Kenya is considered a water deficit countrywith an annual water recharge of 640m 3per capita.Water saving irrigation technologies such as partial root zone drying (PRD) are important means to sustainability produce high yield and quality African leafy vegetables under water limited conditions.PRD is a novel and innovative approach in which half of the root zone is irrigated interchangeably in a planned irrigation schedule.Several researchersin developed countries,particularly those from arid and semiarid,have extensively evaluated PRD as a water saving irrigation strategy on field and horticultural crops without significant influence on both crop yield and quality.PRD actually improves product quality in several crop species as partial root zone drying exploits the drought induced abscisic acid root to shoot signalling to limit stomatal conductance which ultimately saves water.In this paper we reviewPRD results on various field and horticultural crops around the globe with the view of assessing the potential of its implementation in productionof African leafy vegetables in urban and periurban areas in Kenya.
Effect of Biological Control Antagonists Adsorbed on Chitosan Immobilized Silica Nanocomposite on Ralstonia solanacearum and Growth of Tomato Seedlings
(SCIENCEDOMAIN international, 2016-01-11) Gatahi Dennis; Wanyika Harrison; Kihurani Agnes; Gatebe Erastus
Background: Biological control holds promise in managing bacterial wilt disease. However, its efficacy is limited by harsh environmental conditions when applied without use of suitable carrier materials. Aim: The study entailed synthesis of nanocarrier materials for biological control agents (BCAs) using Chitosan and silica nanocomposites. Site and Duration: The experiments were carried out at Jomo Kenyatta University of Agriculture and Technology for a period of two years June 2013 to June 2015. Methodology: The experiments were conducted using a completely randomized design with three replications. Deacetylation, functionalization and immobilization of chitin on mesoporous silica nanoparticles (MSN) to form chitosan immobilized silica nanocomposites (CISNC) gel was done. Results: This resulted in formation of chitosan nanoparticles and CISNC with crystallite sizes of 2.8 and 4.4 nm respectively. BCAs were adsorbed on CISNC gel. Characterization of the bio- nanocomposites showed that they had physisorption properties thus, ideal carriers for BCAs. CISNC gel had the highest significant (P=.05) sorption properties with 75% and 65% adsorption and desorption respectively of BCAs. Efficacy trials were done by in vitro pathogen inhibition and greenhouse bioassays using tomato seedlings. Adsorption of BCAs on CISNC gel significantly (P=.05) increased inhibition efficacy of BCAs on R. solanacearum from 50 to 70%. This was attributed to the antibacterial effect of the individual substances and the overall synergy acquired. Further, BCA-CISNC gel forms a film around root hairs, initiates fast wound healing mechanism and induce prophylactic effect on tomato seedlings challenged with R. solanacearum pathogen, decreasing wilting incidences from 45 to 25%. Additionally, BCA-CISNC complex significantly (P=.05) increased tomato seed germination from 70 to 80% and growth rate from 12 to 15% due to enhanced water utilization efficiency, induced phytohormones and nutritional benefit. BCAs also aided faster nutrient release, absorption and utilization by tomato plants. Conclusion: Therefore, adsorption of bacterial, fungal and phage biocontrol agents on CISNC gel, a complex hitherto not reported to have been used in R. solanacearum disease control, enhanced microbial efficacy against the pathogen and increased tomato productivity.
Use of body linear measurements to estimate liveweight of crossbred dairy cattle in smallholder farms in Kenya
(Springer Plus, 2016-01-22) Lukuyu, M. N.; Gibson, J. P.; Savage, D. B.; Duncan, A. J.; Mujibi, F. D. N.; Okeyo, A. M.
Body linear measurements, and specifically heart girth (HG), have been shown to be useful predictors of cattle liveweight. To test the accuracy of body linear measurements for predicting liveweight, crossbred dairy cattle of different genotypes were measured and weighed. A total of 352 mature cows and 100 heifers were weighed using an electronic weighing scale and measurements of HG, body length, height at withers were taken using an ordinary measuring tape and body condition scored (BCS) using a five-point scale. The animals were grouped according to genotype and age. Genotype classification was undertaken from farmer recall and by visual appraisal as 40–60, 61–80 or 81–100 % exotic (non-indigenous). Age classification was simply as mature cows or heifers. Liveweight of the animals ranged from 102 to 433 kg. Liveweight was strongly correlated with HG (r = 0.84) and body condition scores (r = 0.70) and moderately correlated with body length (r = 0.64) and height at withers (0.61). Regressing LW on HG measurements gave statistically significant (P < 0.01) equations with R2 ranging from of 0.53 to 0.78 and residual standard deviation ranging from 18.11 to 40.50 kg. The overall model developed (adjusted R2 = 0.71) had a prediction error of 26 kg (or 11 % of the mean) and predicted LW of over 95 % of crossbred dairy cattle in the range of 100–450 kg, regardless of age and breed group. Including BCS in the model slightly improved the model fit but not the prediction error. It was concluded that the model can be useful in making general management decisions in smallholder farms.
Molecular Characterization of Wood Ear Mushrooms (Auricularia Sp.) from Kakamega Forest in Western Kenya
(Current Research in Environmental & Applied Mycology, 2016-03-30) Onyango B.O.; Mbaluto C. M.; Otieno D. O.
Mushrooms of the genus Auricularia, generally termed wood ear mushrooms are in high demand in Western Kenya due to their numerous medicinal and nutritional properties. Interventions to characterize and conserve the native wood ear mushrooms are necessary to mitigate possible extinction of this valuable bio-resource. Currently, the species richness and bio-geographical relatedness of the Kenyan native wood ears is not fully elucidated. This study used molecular sequence analysis of the internal transcribed spacer (ITS) and the 28S nuclear ribosomal large subunit (nLSU) genes in species delimitation of six strains of wood ear mushrooms native to Kakamega Forest. Phylogeny of both the ITS and nLSU gene regions showed that three strains clustered with Auricularia delicata while the other three strains clustered with Auricularia polytricha at bootstrap support values of above 97%. An intragenomic dichotomy appeared to occur in the Auricularia delicata strains based on the genetic distance of the nLSU gene sequences. The wood ear mushrooms identified from the Kakamega Forest strains were Auricularia delicata and Auricularia polytricha and not Auricularia auricula as previously reported. This rich biodiversity needs further exploration to widen the nutritional and medicinal base of the rural populace who depend on the mushrooms through conservation, cultivation and commercialization activities.
Screening Napier grass accessions for resistance to Napier grass stunt disease using the loop-mediated isothermal amplification of DNA (LAMP)
(Elsevier, 2017) Wamalwa, N.I.E; Midega, C.A.O; Ajanga, S.; Omukunda, N.E; Muyekho, F.N; Asudi, G.O; Mulaa, M.; Zeyaur, R.K.
Napier grass stunt (NGS) disease is a major threat to Napier grass cultivation and the smallholder dairy industry in East and Central Africa. The disease is caused by a phytoplasma, which is transmitted by the leafhopper Maiestas banda (Kramer) (Hemiptera: Cicadellidae). The current study was conducted to identify among 65 Napier grass accessions that could be resistant to NGS disease using the loopmediated isothermal amplification of DNA (LAMP). The accessions were caged with NGS phytoplasmainfected Napier grass as inoculum source and M. banda as the vector. All Napier grass accessions were subjected to phytoplasma testing thereafter 18 phytoplasma negative and five asymptomatic accessions were selected and used in further screening by subjecting the extracted DNA to LAMP. Plant response to the NGS phytoplasma by symptom expression, impact on yield-related parameters and phytoplasma infection was used to evaluate tolerance or resistance over a period of three months. Most Napier grass accessions were susceptible to the disease except plants belonging to accession 16789 which were negative by LAMP. Napier grass accession 16807 was found to be tolerant with 60% plants positive by LAMP and 90% plants symptomless. Accessions 16822 and 16817 had moderate tolerance with one and two plants positive by LAMP, respectively. Accession 16812 was slightly tolerant with 58.3% plants positive by LAMP and 33.3% of the plants showing symptom remission in the second re-growth. This study indicates there could be resistance and tolerance to NGS disease which could be exploited in the development of an integrated management strategy for this disease.
Growth, Yield and Quality of Baby Corn (Zea Mays L.) And its Fodder As Influenced by Crop Geometry and Nitrogen Application- A Review
(The Biascan, 2017-02-01) EAJAZ AHMAD DAR; ABRAR YOUSUF; MOHAMMAD AMIN BHAT; TODARMAL POONIA
ABSTRACT Baby corn (Zea mays L.) refers to the whole, entirely edible cobs of immature corn harvested just before fertilization at 2-3 cm long silk emergence stage. The baby corn has a medium plant type and provides sweet, succulent and delicious green cobs within 65-75 days of sowing. Crop geometry and nitrogen application are the most important agronomic practices for the higher productivity of baby corn. Most of the researchers have reported improved growth and yield attributes of baby corn with closer crop geometries compared to wider crop geometries, owing to efficient utilization of resources and better harvesting of solar radiation. However, quality attributes were better in wider geometries due to decrease in plant population. It has also been reported that increase in level of nitrogen application results in increased growth, yield and quality of baby corn. However, response to levels of nitrogen application was different for yield and quality attributes

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