Moutia J.-F.Y.,Mauritius Sugar Industry Research Institute |
Saumtally S.,Mauritius Sugar Industry Research Institute
Plant and Soil | Year: 2010
Azospirillum influences growth and development of several crops by producing phytohormones such as auxins which have a major impact on root development. An improved root system leads to better water and nutrient uptake that in turn may influence yield positively. In this study, two agronomically contrasting sugarcane cvs R 570 and M 1176/77 adapted to different agroclimatic zones were inoculated with Azospirillum sp., with and without drought stress, to gauge how far they could benefit from this bacterial association. As early as 103 days after planting, cv M 1176/77 responded positively to inoculation with 15% improved growth (shoot height) and 75% more root dry mass when subjected to drought stress, whereas cv R 570 responded negatively particularly in the absence of drought stress. The significant interaction of cultivar x water regime x Azospirillum inoculation suggests a complex interplay of these factors, possibly involving the indigenous plant auxin pool. Therefore, plant genotype needs to be taken into account when recommending bacterial inoculation for direct plant growth promotion. Furthermore, enhanced growth under sub-optimal water conditions shows clearly the benefits that could be obtained in semi-arid conditions where water deficits frequently occur. © 2010 Springer Science+Business Media B.V.
Van Der Plas G.W.,University of Amsterdam |
De Boer E.J.,University of Amsterdam |
Hooghiemstra H.,University of Amsterdam |
Vincent Florens F.B.,University of Mauritius |
And 3 more authors.
Journal of Quaternary Science | Year: 2012
A 10m long peat core from the Kanaka Crater (20° 25′ S, 57° 31′ E), located at 560m elevation in Mauritius, was analyzed for microfossils. Eight radiocarbon ages show the pollen record reflects environmental and climatic change of the last ca. 38calka BP. The record shows that the island was continuously covered by forest with Erica heath (Philippia) in the uplands. Cyperaceous reedswamp with Pandanus trees was abundant in the coastal lowlands as well as locally in the waterlogged crater. The record shows changes in climatic humidity (wet from 38.0 to 22.7calka BP, drier from 22.7 to 10.6calka BP, and wetter again from 10.6calka BP to recent) as the main response to climate change. A high turnover in montane forest species is evidenced at 22.7calka BP and at the start of the Holocene. The limited altitudinal ranges in the mountains of Mauritius (maximum altitude 828m), and changing humidity being more important than changing temperature, suggests that in response to climate change a reassortment in taxonomic composition of montane forests might be equally important as displacement of forest types to new altitudinal intervals. We found weak impact of the latitudinal migration of the Intertropical Convergence Zone and data suggest that the Indian Ocean Dipole is a more important driver for climatic change in the southwest Indian Ocean. © 2011 John Wiley & Sons, Ltd.
Pynee K.,Mauritius Sugar Industry Research Institute |
Hennequin S.,University Pierre and Marie Curie |
Echternacht L.,University Pierre and Marie Curie |
Echternacht L.,University of Sao Paulo |
Dubuisson J.-Y.,University Pierre and Marie Curie
Phytotaxa | Year: 2012
Crepidomanes minutum (Hymenophyllaceae) is here identified and recorded from Mauritius for the first time. The Mauritian specimens, in addition to those of La Réunion observed at low to middle elevations, are easily distinguished from populations observed outside the Mascarene Archipelago by their dwarfed size and rarity of the stipe proliferation that usually characterizes this species. We thus describe a new variety in this species for the Mascarene Islands. © 2012 Magnolia Press.
Santchurn D.,Mauritius Sugar Industry Research Institute |
Ramdoyal K.,Mauritius Sugar Industry Research Institute |
Badaloo M.G.H.,Mauritius Sugar Industry Research Institute |
Labuschagne M.,University of the Free State
Euphytica | Year: 2012
Apart from sugar production, the sugarcane plant is now viewed as a high value lowcost feedstock for renewable energy. However, in depth studies on the biomass potential of the crop are relatively new and current varieties have not been optimised to achieve the required high biomass yield for different end-uses. The objective of this study was to examine the possibility of using multivariate data analysis (MVDA) techniques in the selection of different types of high biomass canes. Sixty genotypes of different generations of crosses were evaluated for 18 inter-related traits. Principal component analysis compressed the different characters into five major principal components (PCs). The first two explained 77 % of total variation. PC1 emphasised on the cane quality traits while PC2 stressed on biomass characteristics. The biplot with the two PCs was very helpful in visualising the existing variations in the population. Cluster analysis defined six major groups in the population. Candidates from three of them were found suitable for commercial exploitation, for either sugar, fibre, or both as the main end-products. The MVDA techniques were thus found to be very effective in assessing the extent of genetic divergence between genotypes in the population and in the selection of different types of high biomass canes for multipurpose use. It was also clear that sucrose content was positively associated with cane diameter while high fibre varieties tended to be thinner and taller than the traditional commercial varieties. © 2012 Springer Science+Business Media B.V.
Hoi L.W.S.,University of KwaZulu - Natal |
Hoi L.W.S.,Mauritius Sugar Industry Research Institute |
Martincigh B.S.,University of KwaZulu - Natal
International Sugar Journal | Year: 2012
The quality of sugar cane received at Mauritian sugar factories has deteriorated significantly because of increased amounts of extraneous matter delivered in the cane supply. This leads to poorer juice quality and sucrose losses. In this work controlled addition of extraneous matter to clean cane was effected under laboratory conditions to determine the relative impact of dry and green cane leaves and cane tops on the quality of cane and the resulting juice, and to predict their impact on cane processing. Dry leaves produced the most adverse effect on sugar recovery, boiling house recovery and overall recovery. One unit of dry leaves increased fibre % cane, mass of bagasse % cane and sucrose loss in bagasse % cane and in molasses % cane by 0.57, 1.17, 0.030 and 0.011 units respectively, and decreased sugar recovery by 0.23 units. Cane tops increased the amount of fructose and glucose in mixed juice which reduced the Clerget purity of molasses. However, this increased the mass of molasses % cane, which resulted in a much higher sucrose loss in molasses than would have been produced by the same amount of dry leaves. The ill-effect of green leaves was found to be intermediate between that of dry leaves and cane tops.
Ng Cheong L.R.,Mauritius Sugar Industry Research Institute |
Ng Kee Kwong K.F.,Mauritius Sugar Industry Research Institute |
Du Preez C.C.,University of the Free State
Sugar Tech | Year: 2014
Marked differences exist in the properties of the major soil groups of Mauritius on account of differences in age of parent material and in climatic conditions under which these soils have developed. Further differences are expected to be observed in their organic matter and microbial biomass contents as a result of sugarcane cropping. A study was conducted on the four major soil groups of Mauritius to quantify and compare these effects. Organic carbon, total nitrogen and microbial biomass carbon contents were measured for uncropped and cropped conditions. The results showed that soils of Mauritius have average organic carbon and total nitrogen contents of about 100 and 9.5 T/ha for the upper 50 cm layer, and 500 kg/ha of microbial biomass carbon for the upper 15 cm layer. Cropping with sugarcane had variable effects on these three parameters, but did not necessarily cause their degradation. Differences observed could be explained by differences in agronomic practices, as a consequence of differences in rainfall regimes and rock contents. These different agronomic practices include rock-removal for mechanization, cane burning for harvest and addition of organic amendments. © 2013 Society for Sugar Research & Promotion.
Deepchand K.,Mauritius Sugar Industry Research Institute
ACS Symposium Series | Year: 2010
Sugarcane was introduced in Mauritius four centuries ago. Through its considerable resistance and resilience to very adverse climatic conditions like drought and, in particular, intense tropical cyclones, it has proved beyond doubt its capacity to be sustainably cultivated on a long-term commercial basis and to play a multifunctional role. The sugar industry in Mauritius has constantly been faced with challenges and it has always stood up to convert these challenges into opportunities to ensure sustainable productions of sugarcane and derived products derived. Actions taken were mainly in the way of reforms to address technical, financial, socio-economic, and environmental viability of the industry. Appropriate legislations (bearing in mind the specificities of Mauritius as a small island developing state) were put in order to facilitate the sustainability. Copyright. © 2010 American Chemical Society.
Joomun N.,Mauritius Sugar Industry Research Institute |
Dookun-Saumtally A.,Mauritius Sugar Industry Research Institute
Sugar Tech | Year: 2010
Sugarcaneyellow leaf virus (SCYLV) is widely distributed in Mauritius, but so far the characterisation of genotypes of the virus has not been determined. RT-PCR primers were used to identify genetic diversity of the virus in a variety collection plot. Total nucleic acids were extracted from leaves of thirteen introduced varieties infected by SCYLV and a two-step RT-PCR was optimised for each of the three genotype-specific primer pairs CUB-F/CUB-R, REU-F/B-REV, and PER-F/PER-R tested. The presence of three SCYLV genotypes namely the BRA-PER, CUB and REU was confirmed in the germplasm collection. Genotype REU was observed in 10 varieties while 4 varieties were infected by genotype BRA-PER. Mixed infection with genotypes CUB and REU was observed in variety Co6304 while Q88 was co-infected by genotypes BRA-PER and REU. PCR fragments of 363 bp (BRA-PER), 452 bp (CUB) and 905 bp (REU) amplified from varieties PR67245, Co6304 and S17 were cloned and sequenced. Blast analysis of these three sequences showed high homologies with the corresponding genotype sequences from GenBank-100% similarity with isolate Taiwl (AJ491144, BRA genotype), and >99% similarity with isolates CUB-YL1 (AM083988) and REU-YL2 (AM072756) respectively. Recent screening of some local commercial cultivars revealed infection by REU and BRA-PER genotypes. Further intensive surveys are being carried out to assess the distribution of the three SCYLV genotypes in sugarcane fields in Mauritius. © 2011 Society for Sugar Research & Promotion.
Kitson J.J.N.,University of East Anglia |
Warren B.H.,University of Reunion Island |
Vincent Florens F.B.,University of Mauritius |
Baider C.,Mauritius Sugar Industry Research Institute |
And 3 more authors.
Molecular Ecology | Year: 2013
The phytophagous beetle family Curculionidae is the most species-rich insect family known, with much of this diversity having been attributed to both co-evolution with food plants and host shifts at key points within the early evolutionary history of the group. Less well understood is the extent to which patterns of host use vary within or among related species, largely because of the technical difficulties associated with quantifying this. Here we develop a recently characterized molecular approach to quantify diet within and between two closely related species of weevil occurring primarily within dry forests on the island of Mauritius. Our aim is to quantify dietary variation across populations and assess adaptive and nonadaptive explanations for this and to characterize the nature of a trophic shift within an ecologically distinct population within one of the species. We find that our study species are polyphagous, consuming a much wider range of plants than would be suggested by the literature. Our data suggest that local diet variation is largely explained by food availability, and locally specialist populations consume food plants that are not phylogenetically novel, but do appear to represent a novel preference. Our results demonstrate the power of molecular methods to unambiguously quantify dietary variation across populations of insect herbivores, providing a valuable approach to understanding trophic interactions within and among local plant and insect herbivore communities. © 2013 John Wiley & Sons Ltd.
Wong Sak Hoi L.,University of KwaZulu - Natal |
Wong Sak Hoi L.,Mauritius Sugar Industry Research Institute |
Martincigh B.S.,University of KwaZulu - Natal
Industrial Crops and Products | Year: 2013
Sugar cane is a potential source of large amounts of natural fibres which has not yet been adequately exploited. A simple physical method was devised to separate the fibres and the fines/pith from various locations in the plant to yield nine components. The yield of fibres obtained was greatest from the leaves. The fibre/pith ratios of four cane varieties investigated indicated good millability. All the components, except stalk pith, were morphologically similar and FTIR spectroscopy confirmed the lignocellulosic nature of the material. The four components that arise from the cane, namely, rind fibre, rind fines, stalk fibre and stalk pith, showed clear trends in the crystallinity index, combustion temperatures, amount of residue after pyrolysis, percentage carbon content and gross calorific value. The fibres from the leaves and tops did not exhibit clear trends. The information gleaned from this study can be used to select appropriate end-uses for these different fibres. © 2013 Elsevier B.V..