scholarly journals Evaluation of whitefly population and weather effect of cassava mosaic incidence on commonly grown cassava in Benue State, Nigeria

2020 ◽  
Vol 24 (10) ◽  
pp. 1839-1846
Author(s):  
I Time ◽  
E Okoroafor ◽  
J.O. Nwogwugwu ◽  
A.A. Batcho
Keyword(s):  
Wind Speed ◽  
Wind Direction ◽  
Disease Incidence ◽  
Natural Infection ◽  
Block Design ◽  
Mosaic Disease ◽  
Cassava Mosaic Disease ◽  
Whitefly Population ◽  
North East ◽  
Vector Population

Vector population and weather are critical in virus disease incidence and could be strategic for its management in agriculture. To investigate the influence of whitefly population and weather on Cassava Mosaic Disease (CMD) in cassava, TMS 419 and TME 30572, commonly grown in the state were planted. The varieties were laid out in Randomized Complete Block Design in four replicates and left to natural infection by CMD viruses. At two weeks after planting and fortnightly, whitefly population counts were taken, CMD incidence was estimated and severity scored on 5- point scale. Daily temperature, humidity, wind speed and wind direction were obtained as secondary data. Data were analysed using ANOVA at p=0.05. Whitefly population (18/plant) was significant (P≤0.05) in the first 30 days at 26.9-27.1oC, 42% humidity, 10 Km/hr wind speed and when the wind direction was in the East or North-East. The vector population then declined until the end of experiment. Cassava mosaic incidence changed with whitefly population, humidity and wind speed. Disease incidence in cassava plots was low (3.6%). TME30572 maintained lower disease incidence (3.0%) and severity (2.0) during the study. R2 indicated that 27, 42 and 57% of whitefly population could be explained by temperature, humidity and wind speed, respectively while 4% of the disease incidence could be explained by the whitefly population. The number of CMD infected plants peaked (4%) when population of whitefly was 18/plant, above which the disease reduced at 0.0017 rate per unit change in the vector population. Mosaic disease incidence in cassava plots was influenced by vector population as conditioned by the weather. Keywords: Bemisia tabaci, Cassava, Cassava Mosaic Disease, Nigeria, Weather, Whitefly vector

scholarly journals Evaluation and Characterization of High Yielding Cassava Mosaic Resistant Variety YTP2

2021 ◽  
pp. 198-208
Author(s):  
L. Pugalendhi ◽  
M. Velmurugan ◽  
P. S. Kavitha ◽  
M. K. Kalarani ◽  
N. Senthil ◽  
...  
Keyword(s):  
Tamil Nadu ◽  
Starch Content ◽  
Disease Incidence ◽  
Mosaic Disease ◽  
Dna Fingerprint ◽  
Cassava Mosaic Disease ◽  
Resistant Variety ◽  
Research Station ◽  
Internodal Length ◽  
New Variety

The cassava variety YTP2 (Me 681) has been developed through selection from Thondamuthur type at Tapioca and Castor Research Station, TNAU, Yethapur. The performance of YTP2 in the Adaptive Research Trial (ART) and On Farm Trial (OFT) in the farmer’s field inferred that this new variety is well adapted to cassava growing districts of Tamil Nadu. In addition to the above, YTP2 was found to be resistant to cassava mosaic disease incidence (CMD). Plants are erect, medium growing and non-branching type and suitable for growing under irrigated and rainfed conditions. The internodal length is shorter and the leaf size is medium with sufficient canopy. The leaves of the plants droop down to reduce the transpiration loss which is more advantageous to overcome or escape from drought and heat stress during summer season. It is a dual purpose variety wherein the tubers contain high starch content which is much favourable for the manufacture of starch, sago and also suited for table purpose. The overall performance of this variety showed higher tuber yield (42.20 t ha-1) and starch content (28.40%) which is 15.94% and 18.20% increase over the check varieties YTP1 and H226 respectively. The results of DNA fingerprint data involving SSR markers (SSRY235, NS169 and NS928) showed that it is genetically distinct from the existing commercial varieties viz., YTP1, H226 and Sree Athulya.

scholarly journals Effect of Different Planting Material on Physiological Parameters and Cassava Mosaic Incidence in Cassava (Manihot esculenta Crantz.)

2021 ◽  
pp. 20-25
Author(s):  
S. Nanthakumar ◽  
K. Krithika ◽  
M. Prabhu
Keyword(s):  
Disease Incidence ◽  
Block Design ◽  
Maximum Yield ◽  
Matter Content ◽  
Mosaic Disease ◽  
Physiological Parameters ◽  
Dry Matter Content ◽  
Vegetable Crops ◽  
Manihot Esculenta Crantz ◽  
Area Index

An investigation was carried out to assess the effect of planting materials on physiological parameters, cassava mosaic incidence and yield of Cassava varieties viz. H-226 and CO.2 at the Department of Vegetable crops, Horticultural College and Research Institute, TNAU, Coimbatore during September 2010 to June 2011. The experiments were laid out in Factorial Randomized Block Design with four treatments and three replications in two varieties. The results revealed that the tissue culture plants were found be the best in virtue of its high leaf area index, net assimilation rate, dry matter content, tuber yield (26.33 t ha-1) and least incidence of cassava mosaic virus. Among the varieties, CO.2 showed less incidence of CMD. The tissue cultured plants may be recommended to farmers to reduce mosaic disease incidence and get maximum yield in cassava.

scholarly journals Evaluating Performance of Utilizing Onshore Wind Turbines Specifically the Farm Turbines in Kuwait

2019 ◽  
Vol 7 (1) ◽  
pp. 31-48
Author(s):  
Mohammed Salem Alsubai'e ◽  
Saad Abdullah Alshatti
Keyword(s):  
Renewable Energy ◽  
Wind Speed ◽  
Wind Turbines ◽  
Wind Direction ◽  
Onshore Wind ◽  
North East ◽  
The North ◽  
Proportional Relation ◽  
Proper Design ◽  
The Impact

Renewable energy is considered one of the most important and clean sources; since it does not produce any type of emission or pollution. In Kuwait, the energy of wind is existing in three main locations, which are; Ras Jal Aliyah, Bubian in addition to Subiyah, where the characteristics of wind have been evaluated in this paper based on the data generated from the meteorological measurements at 10m height. Also, different studies have been performed in this paper in order to analyze the impact of height on the parameters of wind energy, wind density, in addition to wind speed. Jal Aliyah location has been studied in this paper and the results showed that there is a proportional relation between the wind speed and power, where the maximum power is potential if the speed is equal to 29.1 m/s, and the maximum averaged flux of wind power is equal to 725.54 W/m2. Where both Bubidan Island and Ras Subiyah showed the wind direction in the North-East quadrant with speed is greater than 10 m/s. But, the higher polarized distribution of Jal Aliyah was in the north direction. Based on the obtained results, it can be concluded that this paper provides and suggests a proper design of the wind turbines for designers.

scholarly journals Effective Plant Ages for Screening for Field Resistance to Alternaria Leaf Spot (Caused by Alternaria spp.) under Natural Infection in Jerusalem artichoke (Helianthus tuberosus L.)

Agronomy ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 754 ◽  
Author(s):  
Wanalai Viriyasuthee ◽  
Suwita Saepaisan ◽  
Weerasak Saksirirat ◽  
Mark L. Gleason ◽  
Ruey Shyang Chen ◽  
...  
Keyword(s):  
Leaf Spot ◽  
Disease Incidence ◽  
Natural Infection ◽  
Block Design ◽  
Jerusalem Artichoke ◽  
Plant Age ◽  
Growth Stages ◽  
Alternaria Leaf Spot ◽  
Progress Curve ◽  
The Impact

Host plant resistance has proven to be effective for controlling Alternaria leaf spot on Jerusalem artichoke (JA), but efficient screening techniques have not been developed yet. The objective of this study is to estimate the relationship between disease resistance parameters of JA as a function of plant age. Six JA varieties and three plant ages at the time of inoculation (20, 40 and 60 days after transplanting) (DAT) are evaluated in a factorial experiment in randomized complete block design (RCBD) with four replications. Disease incidence (DI) and severity (DS) are estimated, from which area under the disease progress curve (AUDPC) was calculated. Disease parameters are positively and significantly correlated for plant ages of 40 and 60 DAT. Based on our results, screening of JA at 40 DAT for resistance to Alternaria leaf spot is recommended. Knowledge of the impact of plant age on resistance to key diseases can help breeders to accelerate breeding programs so superior genotypes can be identified before reproductive growth stages.

Effect of African cassava mosaic disease on morphological characteristics of cassava, Manihot esculenta (Crantz)

2015 ◽  
Vol 11 (2) ◽  
pp. 258-265
Author(s):  
TF Oyadiran ◽  
JA Osakwe
Keyword(s):  
Disease Incidence ◽  
Morphological Characteristics ◽  
Field Trials ◽  
Mosaic Disease ◽  
Cassava Mosaic Disease ◽  
Petiole Length ◽  
Manihot Esculenta Crantz ◽  
Key Word ◽  
Mechanized Agriculture ◽  
Number Of Branches

Field trials were conducted with 10 improved clones of cassava to study the effect of ACMD on their morphological characteristics. The clones used were: 97 / 4763, 97/2205, 91/02324, 98/0505, M98/0068, 96/1089A, 96/1632, M98/0040, 99/2123 and 97/0162. The parameters measured were plant height, leaf area, number of branches and petiole length. The research revealed differences within the clones for the parameters studied, these differences seemed to be mainly genetic, as they were not positively correlated to the disease incidence and severity. Based on the findings in this research the following recommendations were made. On the basis of their branching pattern, highly branched clones 97 / 2205, 97/4763 and 98 /0505 are recommended for selection. The heavy branches bear a lot of leaves or produce a thick canopy which helps to reduce the need for weeding, and also reduce the effect of loss of leaves that occur due to disease incidence. However, for industrial / mechanized agriculture, clones that are less branched should be selected as they are easier to harvest mechanically. Though there is disadvantage with their small leaf areas; the crops would have to be highly resistant to fungal attack which tends to cause leaf drop that will reduce leaf material for food / starch production (examples of less branching clones are, M98 / 0068, 96/1632,91/02324).Key Word: African Cassava Mosaic Disease (ACMD), Cassava Mosaic Virus.(CMV)

Bemisia tabaci (Hemiptera: Aleyrodidae) trap catches in a cassava field in Côte d'Ivoire in relation to environmental factors and the distribution of African cassava mosaic disease

1998 ◽  
Vol 88 (4) ◽  
pp. 369-378 ◽  
Author(s):  
J. Colvin ◽  
L.D.C. Fishpool ◽  
D. Fargette ◽  
J. Sherigton ◽  
C. Fauquet
Keyword(s):  
Bemisia Tabaci ◽  
Wind Direction ◽  
Time Of Day ◽  
Mosaic Disease ◽  
Cultural Control ◽  
African Cassava Mosaic Virus ◽  
Cassava Mosaic Disease ◽  
Wind Speeds ◽  
Prevailing Wind Direction ◽  
Cassava Crop

AbstractAfrican cassava mosaic virus (ACMV), vectored by the whitefly, Bermisia tabaci (Gennadius), is considered the most damaging pathogen of any African crop. Information about vector movement is important for understanding the epidemiology of this disease and the experiments reported here were designed to examine B.tabaci flight activity both in and around a cassava crop in relation to time of day, crop growth stage, wind direction and speed, and to the resulting pattern of infected plants within the field at harvest. At wind speeds of <0.4 ms−1 adult B. tabaci approached the yellow traps by flying upwind. At greater wind speeds, significantly fewer B. tabaci adults approached the traps from downwind, thus reversing the directionally of the catch. When the direction of the prevailing south-west wind reversed, so did the directionality of the catch. Bemisia tabaci adults were flight active throughout the day and the greatest percentage were caught above the canopy between 06.00–08.00 h, when wind speeds were lowest. Trap height and position significantly affected catch with the greatest numbers caught on the lowest traps. More than three times as many B. tabaci adults were caught on traps situated downwind from the field compared to those upwind. Suggesting that the field was acting as a source of whiteflies. In both years, Africa cassava mosaic disease (ACMD) incidence was highest and lowest, respectively, on the edges and in the middle of the trials, with the highest incidence occuring on the edges facing the prevailing wind direction. These results are discussed in relation to the epidemiology of ACMD and to potential cultural control methods such as the use of ACMD-resistant guard rows to protect a mainly susceptible crop.

scholarly journals Genotype × Environment Interaction of Mosaic Disease, Root Yields and Total Carotene Concentration of Yellow-Fleshed Cassava in Nigeria

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Norbert G. Maroya ◽  
Peter Kulakow ◽  
Alfred G. O. Dixon ◽  
Busie B. Maziya-Dixon
Keyword(s):  
Block Design ◽  
Matter Content ◽  
Mosaic Disease ◽  
Sum Of Squares ◽  
Cassava Mosaic Disease ◽  
Environment Interaction ◽  
Dry Matter Content ◽  
Root Yield ◽  
Genotype Environment Interaction ◽  
Agroecological Zones

Twenty-one yellow-fleshed cassava genotypes were evaluated over two years in five major cassava growing agroecological zones in Nigeria. The trials were established in a randomized complete block design with four replications to assess genotype performance and Genotype × Environment interaction for cassava mosaic disease (CMD), fresh and dry root yield (FYLD; DYLD), root dry matter content (DMC), and total carotene concentration (TCC). Combined analysis of variance showed significant differences (P<0.001) among genotypes (G), environment (E), and Genotype × Environment interaction (GE) for all the traits tested. For reaction to CMD, the best genotypes showing stable resistance were TMS 07/0539 and TMS 07/0628. For root yield, the best genotypes were TMS 01/1368 and TMS 07/0553. Genotype TMS 07/0593 was the best for DMC and TCC across the 10 environments. Variation among genotypes accounted for most of the Total Sum of Squares for CMD (72.1%) and TCC (34.4%). Environmental variation accounted for most of the Total Sum of Squares for FYLD (42.8%), DYLD (39.6%), and DMC (29.2%). This study revealed that TMS 07/0593 has the highest and most stable TCC, DMC with the lowest CMD severity score and appeared to be the best genotype.

scholarly journals Field Evaluation of Some Cassava Cultivars against the African Cassava Mosaic Disease in the Humid Forests of Cameroon

2019 ◽  
pp. 1-8
Author(s):  
A. Mogo ◽  
J. Fomekong Nopogwo ◽  
E. L. Ngonkeu Mangaptche ◽  
R. Ghogomu Tamouh ◽  
E. Temgoua ◽  
...  
Keyword(s):  
Large Scale ◽  
Block Design ◽  
Field Evaluation ◽  
Mosaic Disease ◽  
Annual Production ◽  
Cassava Mosaic Disease ◽  
Yield Performance ◽  
Randomized Complete Block Design ◽  
Cassava Production ◽  
Improved Cultivars

There is a considerable deficit in the annual production of cassava in Cameroon of about 31 million tons, and this has been mainly due to constraints related to pest attacks and most especially diseases like the African Cassava Mosaic Disease (ACMD). This study was therefore undertaken on three sites in the locality of Bityili (South Region of Cameroon), to determine amongst improved and local cassava cultivars those that provide resistance to the development of the ACMD. The severity and incidence of this disease was evaluated and its impact on cassava yield. In each site, cassava was grown in a randomized complete block design. The local cultivars (Ekobele and Ngon kribi) showed higher severity (76-100%) and incidence of ACMD compared to the improved cultivars (TMS 92/0326 and TMS 96/1414) of 0-25% and 0-10%, respectively. Strong inverse correlations were observed between ACMD severity and yield performance, measured in terms of number of tubers/plant and weight of fresh tubers. The improved cultivars, TMS 92/0326 and TMS 96/1414, could, therefore, be recommended for large-scale planting in a bid to promote cassava production in the South Region of Cameroon.

scholarly journals Effective isolation distance for prevention of cassava virus infections in Uganda

2020 ◽  
Vol 28 (s1) ◽  
pp. 1-13
Author(s):  
F. Kasule ◽  
P. Wasswa ◽  
S.B. Mukasa ◽  
A. Okiror ◽  
A.W. Mwang’ombe
Keyword(s):  
Tissue Culture ◽  
Agricultural Research ◽  
Block Design ◽  
Mosaic Disease ◽  
Cassava Mosaic Disease ◽  
Viral Diseases ◽  
Virus Infections ◽  
Isolation Distance ◽  
Isolation Distances ◽  
Research Institute

Cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) are the major viral diseases of cassava in Uganda. Although isolation distance of “50 m” has been recommended by MAAIF in Uganda for prevention of virus infections in crops, the minimum isolation distance has not been verified for effectiveness in cassava. This study assessed the effective isolation distance for management of viral diseases in cassava. Virus-clean cassava cultivars (NASE 03, NASE 14 and NAROCASS 1) from farmers’ fields were used as field sourced (FS) planting materials. Tissue culture (TC) material of the same cultivars were sourced from the National Crops Resources Research Institute and Makerere University Agricultural Research Institute tissue culture laboratories. Both FS and TC materials were tested at isolation distances of 50, 100, 150 and 250 m for virus prevention. The experiment was laid out in a randomised complete block design and was run for 12 months after planting (MAP). Mean CBSD/CMD prevalence significantly varied (P<0.05) among isolation distances in both FS and TC plants, and the 250 m isolation distance was the most effective in reducing disease prevalence. Across cultivars and planting material category at 12 MAP, the 50 m isolation distance had the highest foliar incidence for CBSD (29.2%) and CMD (16.1%); while severity for CBSD was 1.4 and 1.2 for CMD. At 250 m, all FS and TC plants had CBSD/CMD severity of 1.0 and 0% incidence. These results show that 250 m isolation distance can provide an option to disseminate popular, but CBSD/CMD susceptible cassava cultivars thereby manage CBSD/CMD.  

scholarly journals Genotypic Variability in Some Morpho-Physiological Traits in Different Environments and Their Relationship with Cassava (Manihot esculenta Crantz) Root Yield

2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Joseph Adjebeng-Danquah ◽  
Isaac Kwadwo Asante ◽  
Joseph Manu-Aduening ◽  
Richard Yaw Agyare ◽  
Vernon Edward Gracen ◽  
...  
Keyword(s):  
Block Design ◽  
Principal Component ◽  
Mosaic Disease ◽  
Physiological Traits ◽  
Cassava Mosaic Disease ◽  
Environment Interaction ◽  
Gge Biplot ◽  
Root Yield ◽  
Manihot Esculenta Crantz ◽  
Drought Tolerant

Cassava root yield under diverse environments is influenced by morpho-physiological traits that are in turn influenced by genotype, environment, and genotype × environment interaction (GEI). Most GEI analyses in cassava have been limited to root yield with less emphasis on stability of other yield-related traits. This study was carried out to assess the effect of GEI on some morpho-physiological traits in cassava and key traits that are useful for selection in different environments. The study utilized 20 cassava genotypes evaluated in six environments, namely, Fumesua 2013 and 2014, Nyankpala 2013 and 2014 (irrigation), and Nyankpala 2013 and 2014 (no irrigation). The genotypes were arranged in a randomized complete block design (RCBD) with three replications and assessed for a number of morpho-physiological traits, root yield and yield components. The data were subjected to analysis of variance using SAS statistical package. Subsequently, the GGE biplot was used to carry out genotype × environment, genotype × trait, and environment × trait interaction analyses to determine the specificity of genotypic performance and traits linked to particular environments. The results indicated significant (P<0.05) GEI effect on all traits except leaf temperature. The genotype × trait biplot analysis revealed closely related traits and those associated with root yield and genotypes that show weakness in these traits. Both environment × trait biplot and principal component analyses identified traits with higher discriminatory power among genotypes in various environments particularly in the dry environments. These can be used as secondary traits to select drought-tolerant genotypes. From this study, the GGE biplot was useful in identifying traits associated with specific genotypes in different environments to aid in selection. Moderate broad-sense heritability estimates werefound for storage root yield, harvest index, plant height, ratio of storage rootlength to girth, and cassava mosaic disease score indicating that progresscan be made through selection for these traits.

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