SIMULATION OF THE DYNAMICS OF CASSAVA STEM CUTTINGS ON AN INCLINED WOOD SURFACE

Development of precision machines to handle some of the field activities involved in the cultivation of cassava is a highly welcomed project among young enterprising farmers who are keen in resolving the posterity of their wellbeing as a big time farmer. Mechanization of cassava in the tropics is grossly hampered by lack of extensive knowlegde on the behaviour, physical properties of cassava stems and parameters that have great influence on the handling of the stems during cultivation, hence the limita-tion of advancing the present semi-automatic planter to fully automated one is still a mirage in the tropics. This paper presents the flow properties of cassava cuttings that can lend it to proper handling in a metering machine. A variable inclined wood surface rig with an ejection outlet was used to study the properties of the stem. Measured cassava stem predictive parameters; diamater, lentgh,weight; angle variation on the rig; response parameters; percentage ejected, percentage sliding through, forces acting on stems were obtained. The results from the study could be used to predict acurately the exact dynamics of a given stem isolated from the bulk of stem cuttings stacked in the metering hopper. Models to predict the flow properties of the stems were obtained; further simulation of the dynamics was embarked upon using MATLAB software. A major transition zone of stem characteris-tics per pecentage sliding to ejection occurred within the range of angles of 150 -300. This might be a favourable angular zone for isolating the stems from the bulk mass while the effectively isolated stems can be metered appropriately by another mechanism in the process of developing a metering device for cassava stem cuttings.

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Development of a triple antibody sandwich enzyme-linked immunosorbent assay for cassava mosaic disease detection using a monoclonal antibody to Sri Lankan cassava mosaic virus

Virology Journal ◽

10.1186/s12985-021-01572-6 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Saengsoon Charoenvilaisiri ◽

Channarong Seepiban ◽

Mallika Kumpoosiri ◽

Sombat Rukpratanporn ◽

Nuchnard Warin ◽

...

Keyword(s):

Mosaic Virus ◽

Immunosorbent Assay ◽

Mosaic Disease ◽

Cassava Mosaic Disease ◽

Enzyme Linked Immunosorbent Assay ◽

Sri Lankan ◽

Stem Cuttings ◽

Field Samples ◽

Cassava Stem ◽

Cassava Mosaic Virus

Abstract Background Cassava mosaic disease (CMD) is one of the most devastating viral diseases for cassava production in Africa and Asia. Accurate yet affordable diagnostics are one of the fundamental tools supporting successful CMD management, especially in developing countries. This study aimed to develop an antibody-based immunoassay for the detection of Sri Lankan cassava mosaic virus (SLCMV), the only cassava mosaic begomovirus currently causing CMD outbreaks in Southeast Asia (SEA). Methods Monoclonal antibodies (MAbs) against the recombinant coat protein of SLCMV were generated using hybridoma technology. MAbs were characterized and used to develop a triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) for SLCMV detection in cassava leaves and stems. Assay specificity, sensitivity and efficiency for SLCMV detection was investigated and compared to those of a commercial ELISA test kit and PCR, the gold standard. Results A TAS-ELISA for SLCMV detection was successfully developed using the newly established MAb 29B3 and an in-house polyclonal antibody (PAb) against begomoviruses, PAb PK. The assay was able to detect SLCMV in leaves, green bark from cassava stem tips, and young leaf sprouts from stem cuttings of SLCMV-infected cassava plants without cross-reactivity to those derived from healthy cassava controls. Sensitivity comparison using serial dilutions of SLCMV-infected cassava sap extracts revealed that the assay was 256-fold more sensitive than a commercial TAS-ELISA kit and 64-fold less sensitive than PCR using previously published SLCMV-specific primers. In terms of DNA content, our assay demonstrated a limit of detection of 2.21 to 4.08 × 106 virus copies as determined by quantitative real-time PCR (qPCR). When applied to field samples (n = 490), the TAS-ELISA showed high accuracy (99.6%), specificity (100%), and sensitivity (98.2%) relative to the results obtained by the reference PCR. SLCMV infecting chaya (Cnidoscolus aconitifolius) and coral plant (Jatropha multifida) was also reported for the first time in SEA. Conclusions Our findings suggest that the TAS-ELISA for SLCMV detection developed in this study can serve as an attractive tool for efficient, inexpensive and high-throughput detection of SLCMV and can be applied to CMD screening of cassava stem cuttings, large-scale surveillance, and screening for resistance.

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Effect of different temperature regimes on physiological changes associated with early growth of cassava stem cuttings

Discovery and Innovation ◽

10.4314/dai.v15i3.15637 ◽

2005 ◽

Vol 15 (3) ◽

Author(s):

SO Akparobi ◽

MO Akoroda ◽

IJ Ekanayake

Keyword(s):

Early Growth ◽

Stem Cuttings ◽

Physiological Changes ◽

Temperature Regimes ◽

Cassava Stem

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Virus-Free Shoots from Cassava Stem Cuttings Infected with Cassava Latent Virus

Plant Disease ◽

10.1094/pd-69-231 ◽

1985 ◽

Vol 69 (3) ◽

pp. 231 ◽

Cited By ~ 10

Author(s):

R. P. Pacumbaba

Keyword(s):

Latent Virus ◽

Stem Cuttings ◽

Cassava Stem ◽

Cassava Latent Virus

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Climatic change of Bangladesh over a cycle of period 35 years

Journal of Bangladesh Academy of Sciences ◽

10.3329/jbas.v39i1.23661 ◽

2015 ◽

Vol 39 (1) ◽

pp. 73-82

Author(s):

M Abdullah Ansary ◽

M Alamgir Hossain

Keyword(s):

Climate Changes ◽

Monsoon Rainfall ◽

Great Influence ◽

Climatic Changes ◽

Geological Materials ◽

The Past ◽

Future Situation ◽

Weather Parameters ◽

The Tropics ◽

Academy Of Sciences

Bangladesh has been undergoing hazardous climatic changes. Monsoon is changing its pattern. Variations of temperature, humidity, rainfall are remarkable. The seasonal changes of Bangladesh such as the transition from winter to spring, summer to autumn in temperate zone, and from wet to dry in the tropics are remarkable to take into consideration. The climatic changes have great influence on the distribution of plants and animals and in the formation of soils through the weathering of geological materials and the decomposition or preservation of organic matter. Various weather parameters over a cycle were studied and determined the coefficient of variations to compare the past, present and future situation in Bangladesh. The frequency distribution and the shift in distribution of monsoon rainfall were determined and analyzed to show the trend of climate changes and their impact on environment. The important findings are the surface temperature rise by 0.60C and the rainfall in monsoon likely to be increased by 12% in the year 2030. However, the seasonal rainfall trend is decreasingJournal of Bangladesh Academy of Sciences, Vol. 39, No. 1, 73-82, 2015

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Widmer, Ernst (1927--1990)

Routledge Encyclopedia of Modernism ◽

10.4324/9781135000356-rem1087-1 ◽

2018 ◽

Author(s):

Paulo Costa Lima

Keyword(s):

Contemporary Music ◽

Great Influence ◽

Decisive Role ◽

Extreme Value ◽

Entire Life ◽

School Of Music ◽

The Creation ◽

Way Of Thinking ◽

Almost All ◽

The Tropics

Ernst Widmer considered himself a Brazilian citizen, a Brazilian composer who was born and educated in Switzerland but who bloomed in the tropics. Actually, the theme of the cultural crossing was of great importance for the elaboration of his way of thinking and of composing. He dedicated almost all his entire life to the School of Music of the Federal University of Bahia (UFBA), where he taught between 1956 and 1987. During that period, he had a decisive role in turning Salvador into one of the most important centers of contemporary music in Brazil. In particular, he was in charge of the formation of composers, making this activity the basis for his intense artistic performance, which resulted in the composition of about two hundred opuses and thirty-one awards. He exerted great influence on his students and several of them became well known composers, and he also gave extreme value to singularity as a pedagogical parameter, having inspired the creation of the Group of Composers from Bahia in 1966, whose manifest of just one line rejected as a principle any declared principles. After his retirement in 1987, he renewed his ties with his native city in Switzerland, debuting several of his pieces and participating in the creation of the Ernst Widmer Gesellschaft dedicated to promoting his music.

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The Survival Rate and Starch Histochemical Assay of Various Stem Cutting Conditions of Mentega 2 Cassava Genotype at Initial Growth Stage

BIOEDUSCIENCE ◽

10.22236/j.bes/515612 ◽

2021 ◽

Vol 5 (1) ◽

pp. 40-48

Author(s):

Sri Hartati ◽

Hani Fitriani ◽

Nanang Taryana ◽

Nawawi Nawawi ◽

Yani Cahyani ◽

...

Keyword(s):

Survival Rate ◽

Starch Content ◽

Stem Cutting ◽

Growth Stages ◽

Initial Growth ◽

Stem Cuttings ◽

Node Number ◽

Emergence Period ◽

Stem Size ◽

Cassava Stem

Background: This study aimed to evaluate the growth ability of cassava mini stem cuttings with different node number and a variety of stem cutting shapes and their correlation with starch content in the stems at initial growth stages. Methods. In this study, the viability of cassava stem cuttings was identified in two type experiments i.e. mini-stem cuttings consisting 1 and 2 nodes and shape variation of single node mini-stem cutting. Parameters observed were shoots emergence period, number of sprouting cuttings, shoots number of individual stem cuttings, shoots height and number of leaves. In addition, starch histochemical test was also carried out on stems of young shoots and initial stem cuttings using Lugol’s solution. Results. Both cassava stem cuttings consisting of 1 and 2 buds indicated the same survival rate of 100%. 1 bud stem cuttings with different shapes showed different survival rate, i.e. 60-80% for semicircular and fully circular cuttings and 30-40% for box shape cuttings. The difference in survival rate with different stem size is probably related to the availability of the amount of starch to support shoots growth. Observations at week 3 after planting generally showed that the stem cuttings with 2 buds were higher than those of stem with 1 bud. Conclusion: There were differences in the scores on the starch content test qualitatively with Lugol staining, in various parts of the plant originating from 1 bud and 2 bud cuttings which may indicate a breakdown of starch during shoot development.

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Welfare and Productivity Impact of Adoption of Biofortified Cassava by Smallholder Farmers in Nigeria

10.21203/rs.3.rs-47869/v1 ◽

2020 ◽

Author(s):

ADETOMIWA KOLAPO ◽

Adeyera James Kolapo

Keyword(s):

Instrumental Variable ◽

Smallholder Farmers ◽

Farm Size ◽

Stem Cuttings ◽

Household Level ◽

Instrumental Variable Regression ◽

Level Data ◽

Poverty Status ◽

Cassava Stem ◽

Distributional Impact

Abstract In the bid to improve the productivity, welfare and vitamin-A intake of SSA farmers, Biofortified cassava was bred. This study examined the welfare and productivity impact of adoption of biofortified cassava using a household-level data from smallholder farmers in Nigeria. We used instrumental variable regression to control for endogeneity. The results obtained from the study showed that adoption of biofortified cassava increased farm yield, farmers income and welfare outcomes of adopters of biofortified cassava. In addition, the distributional impact of the adoption of the biofortified cassava showed heterogeneity effect based on gender and farm size. Overall, the study suggests that since the largest proportion of the cassava farmers in Nigeria are mostly smallholder farmers, distribution and circulation of biofortified cassava stem cuttings should be targeted towards the smallholder farmers so as to improve their productivity, income and welfare and subsequently reduce their poverty status and ensure food security.

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Phase separation in sol gel-derived ceramic films of silica-zirconia, alumina-zirconia, and titania-zirconia system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170967 ◽

1994 ◽

Vol 52 ◽

pp. 646-647

Author(s):

J. Tong ◽

L. Eyring

Keyword(s):

Fracture Toughness ◽

Phase Separation ◽

Sol Gel ◽

Great Influence ◽

High Strength ◽

Chemical Durability ◽

Separation Method ◽

Toughening Mechanism ◽

Ceramic Films ◽

Zirconia Toughened Alumina

There is increasing interest in composites containing zirconia because of their high strength, fracture toughness, and its great influence on the chemical durability in glass. For the zirconia-silica system, monolithic glasses, fibers and coatings have been obtained. There is currently a great interest in designing zirconia-toughened alumina including exploration of the processing methods and the toughening mechanism.The possibility of forming nanocrystal composites by a phase separation method has been investigated in three systems: zirconia-alumina, zirconia-silica and zirconia-titania using HREM. The morphological observations initially suggest that the formation of nanocrystal composites by a phase separation method is possible in the zirconia-alumina and zirconia-silica systems, but impossible in the zirconia-titania system. The separation-produced grain size in silica-zirconia system is around 5 nm and is more uniform than that in the alumina-zirconia system in which the sizes of the small polyhedron grains are around 10 nm. In the titania-zirconia system, there is no obvious separation as was observed in die alumina-zirconia and silica-zirconia system.

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