African Sugarcane Research Articles

Silicon reduces impact of plant nitrogen in promoting stalk borer (Eldana saccharina) but not sugarcane thrips (Fulmekiola serrata) infestations in sugarcane.

The stalk borer Eldana saccharina Walker (Lepidoptera: Pyralidae) is a major limiting factor in South African sugarcane production, while yield is also reduced by sugarcane thrips Fulmekiola serrata Kobus (Thysanoptera: Thripidae). Borer management options include appropriate nitrogen (N) and enhanced silicon (Si) nutrition; the effect of N on sugarcane thrips is unknown. We tested the effects of these nutrients, in combination with resistant (N33) and susceptible (N27) sugarcane cultivars, on E. saccharina and F. serrata infestation. Two pot trials with three levels of N (60, 120, and 180 kg ha-1) and two levels each of calcium silicate and dolomitic lime (5 and 10 t ha-1) were naturally infested with thrips, then artificially water stressed and infested with borer. Higher N levels increased borer survival and stalk damage, while Si reduced these compared with controls. Silicon significantly reduced stalk damage in N27 but not in N33; hence, Si provided relatively greater protection for susceptible cultivars than for resistant ones. High N treatments were associated with greater thrips numbers, while Si treatments did not significantly influence thrips infestation. The reduction in borer survival and stalk damage by Si application at all N rates indicates that under field conditions, the opportunity exists for optimizing sugarcane yields through maintaining adequate N nutrition, while reducing populations of E. saccharina using integrated pest management (IPM) tactics that include improved Si nutrition of the crop and reduced plant water stress. Improved management of N nutrition may also provide an option for thrips IPM. The contrasting effects of Si on stalk borer and thrips indicate that Si-mediated resistance to insect herbivores in sugarcane has mechanical and biochemical components that are well developed in the stalk tissues targeted by E. saccharina but poorly developed in the young leaf spindles where F. serrata occurs.

Evaluation of Trinexapac-ethyl (Moddus®) as a New Chemical Ripener for the South African Sugarcane Industry

Although information from Brazil and Australia indicate that trinexapac-ethyl (Moddus®) is an excellent new sugarcane ripener, there is no information on the response of South African varieties to this chemical. The objective of this investigation was to establish the ripening potential of this chemical in a local variety and to compare responses with current industry standards, 2-chloroethyl phosphonic acid (Ethephon®) and fluazifop-p-butyl (Fusilade Forte®). Evaluation was conducted in an irrigated plant and first ratoon crop of variety N32 at Pongola, South Africa. The field trial was laid out as a complete randomised design with five replicates per treatment. The nine treatments comprised: (a) untreated control, (b) Ethephon® (1.5 L/ha) applied 84 days before harvest (DBH), (c) Fusilade Forte® (0.2 L/ha) applied 43 DBH, (d) Moddus® at three rates (0.8, 1 and 2 L/ha) applied 70 DBH, (e) Ethephon® (1.5 L/ha) and Fusilade Forte® (0.2 L/ha) applied in combination 84 and 43 DBH, and (f) Moddus® (0.8 and 1 L/ha) and Fusilade Forte® (0.2 L/ha) applied in combination 70 and 43 DBH. The various ripener treatments improved estimated recoverable crystal (ERC) yields in the 12-month old crops by between 1.6 and 4.9 t/ha when compared with the control. Moddus® applied at 0.8 and 1 L/ha achieved similar improvements as Fusilade Forte® and Ethephon®, but at 2 L/ha outperformed the latter two ripeners by up to 1.9 t ERC/ha. Best ERC yield responses were achieved in the three combination treatments. However, the Moddus®—Fusilade Forte® combination treatments outperformed the standard Ethephon®—Fusilade Forte® combination treatment by up to 1 t ERC/ha. These results indicate that Moddus® is an effective sugarcane ripener under South African high-potential irrigated conditions and that improved in ERC yields exceeding those obtained with current industry standards might be possible.

Logistic Regression Models to Aid Selection in Early Stages of Sugarcane Breeding

In sugarcane breeding, visual appraisal is used to select for cane yield among seedlings (Stage I) and non-replicated clonal plots (Stage II). Genotype by environment interaction and interplot competition reduces selection efficiency. Although path coefficient analysis studies identified important yield components for indirect selection, currently there is little integration of that knowledge in models to improve early stage selection. This study demonstrates the use of logistic regression models as a statistical decision support tool that uses simultaneous selection for yield components (stalk number, stalk height, stalk diameter, estimable recoverable crystal (ERC) % cane) to help identify genotypes that produce high yield in non-replicated stages of sugarcane breeding. Data were collected from two Stage I populations grown at the USDA-ARS, Sugarcane Research Station at Houma and LSU AgCenter, Sugar Research Station, St. Gabriel, Louisiana, USA and two Stage II populations grown at Gingindlovu and Empangeni research stations, South African Sugarcane Research Institute, in South Africa. The data were analyzed using the logistic procedure of the statistical analysis system. Genotypes selected using the logistic regression models produced higher yield and larger values for yield components than those not selected. Stalk number was the most influential yield component while ERC% cane was the least. The logistic regression models identified the yield components that contributed significantly to yield for each population. The differences in variability within and among the populations provided guidance as to the precision of selection and therefore could indicate to the breeder the need for a higher or lower selection rate. Higher discriminating ability between selected and rejected genotypes indicated greater precision of selection.

Are Native Predators Likely to Influence the Establishment and Persistence ofAnthonomus santacruzi(Curculionidae), a Biological Control Agent ofSolanum mauritianum(Solanaceae) in South Africa?

Solanum mauritianum Scop. (bugweed, woolly nightshade, Solanaceae), a perennial small tree that is native to South America, threatens several commercial and conservation activities in the eastern higher rainfall regions of South Africa and has thus been targeted for biological control (see review by Olckers 2011). The flowerbud-feeding weevil Anthonomus santacruzi Hustache (Coleoptera: Curculionidae), which has the potential to reduce the weed's excessive fruit set, was first released in South Africa in late 2008 (Olckers 2003, 2008) and is currently the subject of extensive release efforts to promote its establishment and distribution. Mass-rearing by the South African Sugarcane Research Institute since 2011 has so far facilitated the release of several thousand weevils in the province of KwaZulu-Natal (D. Gillespie, pers. comm.).

Using logistic regression models for selection in non-replicated sugarcane breeding populations

Increasing selection efficiency in un-replicated populations has remained a challenge to sugarcane breeders due to the effects of genotype by environment interaction and competition among plots. Therefore studies aimed at exploring models to improve selection efficiency are required. At the South African Sugarcane Research Institute, the Stage II selection populations are planted to un-replicated plots. Visual selection, which is known to be subjective, is used to determine the genotypes advanced. Although path coefficient analysis has identified important yield components, there is little use of that knowledge to enhance selection. This study demonstrates the use of logistic regression model as a statistical decision support tool to enhance selection in un-replicated populations. The logistic regression model used stalk number, stalk height, stalk diameter and estimable recoverable crystal (ERC) % cane to predict sugar yield. The data were collected from Stage II populations across regional breeding programs and analysed using the logistic procedure of Statistical Analysis System. The Likelihood Ratio, Score and Wald statistics were highly significant (P < 0.0001) indicating the robustness of the models. Stalk number is the most influential component to sugar yield followed by diameter, height and ERC % cane. The coefficients of the yield components varied across different programs indicating the potential of the analysis to determine yield component combination. Genotypes selected using the models produced significantly higher trait values than those rejected. The logistic regression models should enhance selection efficiency in un-replicated populations as well as provide for the evaluation of breeding populations and trait combinations across regional breeding programs.

PROGRESS IN RESEARCH ON GENETICALLY MODIFIED SUGARCANE IN SOUTH AFRICA AND ASSOCIATED REGULATORY REQUIREMENTS

Research on improvement of sugarcane by genetic engineering has been undertaken by the South African Sugarcane Research Institute (SASRI) for the last 18 years. Modifications include tolerance to herbicides (glyphosate and glufosinate ammonium) and the lepidopteran stalk borer Eldana saccharina via cry1A(b) gene insertion as well as perturbations to enzymes involved in sucrose metabolism (e.g., up- and/or down-regulation of phosphofructokinase and neutral invertase). Sugarcane containing these traits has been evaluated in confined field trials at SASRI. Field-grown transgenic material is subjected to agronomic characterization and molecular analysis to determine stability and heritability of the inserted characteristic over successive growing seasons/harvest cycles. Although no genetically modified (GM) sugarcane is grown commercially in South Africa, activities involving research and both trial and commercial release of GM crops in the country are regulated by the GMO Act (Act 15, 1997) which is administered by the Directorate Plant Genetic Resources of the Department of Agriculture, Forestry and Fisheries. Field trials can be conducted on receipt of a Trial Release Permit (i.e., intentional introduction to the environment) once a transgenic line has undergone preliminary molecular screening. Permit conditions stipulate activities such as regular field inspections, submission of annual reports, appropriate monitoring and record-keeping and destruction of test material on termination of the trial. To release commercial GM sugarcane, a General Release Permit would be required but such applications are in abeyance while issues such as intellectual property and market-related issues are under scrutiny.

Family selection gains for quality traits among South African sugarcane breeding populations

In sugarcane breeding, family selection has been shown to produce larger gains than individual plant selection. During family selection, whole families of seedlings are selected or rejected based on data derived from replicated family plots. The objective of this study was to determine predicted family selection gains and evaluate their implications for variety improvement in terms of quality traits among sugarcane breeding populations of the South African Sugarcane Research Institute's regional breeding programmes. The data was collected from seven breeding populations and analysed using the Statistical Analysis System (SAS). All the quality traits showed highly significant family effects variance components. There were consistent increases in heritability and gains to selection with advancing population series indicating benefits from indirect recurrent selection. Brix % cane, because it costs less to measure, could be used to evaluate within family variability. The B, C, U and F populations produced larger and more consistent selection gains than K, T and S. Recurrent selection could be used to enhance breeding for quality traits.

Optimum replications and crop-years for sugarcane genotype trials at Dwangwa Sugar Estate in Malawi

The ability to detect significant differences among genotypes in trials depends on the variance associated with the means. Dwangwa Sugar Estate, Malawi, imports genotypes from the South African Sugarcane Research Institute (SASRI) to test for possible commercial release. The objective of this study was to determine the optimum number of replications and crop-years required for adequate discriminating ability for yield and quality parameters. Data for yield (cane and sugar) and quality (estimable recoverable crystal [ERC %] and fibre %) were collected from two trial series. Each trial had eight replications and was harvested in the plant and four ratoon crops. The data were analysed using the MIXED procedure of the Statistical Analysis System (SAS) to estimate the variance components used to calculate broad-sense heritabilities (BSH). The optimum number of replications and crop-years was modeled using BSH. Yield traits produced more significant variance components for genotype by environment interaction (G×E) than quality traits. Quality traits produced larger BSH than yield traits. Four replications and harvesting in the plant and three ratoon crops provided adequate discriminating ability among genotypes. The resources saved by reducing replications could be used to plant more trials on different soil types to exploit or minimise G×E.

Molossid bats in an African agro-ecosystem select sugarcane fields as foraging habitat

Two coexisting species of African molossids, the little free-tailed bat, Chaerephon pumilus, and the Angolan free-tailed bat, Mops condylurus, were studied in the lowveld of Swaziland. Nine C. pumilus and five M. condylurus, all non-lactating females, were radio-tracked in order to investigate their habitat utilization. The results confirmed that both of these species selected to forage over sugarcane fields instead of over the other habitats available in the area: savanna, riparian forest and urban areas. Foraging ranges were relatively large with C. pumilus travelling on average a maximum of 4.2 km from the roost and M. condylurus covering 4.8 km. The mean activity areas ranged from 976 ha (minimum convex polygon) to 1319 ha (95% kernel) for C. pumilus and from 1190 ha (MCP) to 1437 ha (95% kernel) for M. condylurus. Interspecific differences in the mean activity area or maximum distance travelled were not found. The results of this study suggest that these species have a potential role as pest-controlling agents over sugarcane fields.

Trends and Implications of Genotype by Environment Interaction in South African Sugarcane Breeding

Genotype by environment interaction (GxE) influences and complicates the selection of superior genotypes in trials by confounding the determination of true genetic values. In South Africa, variety trials are planted at several locations and harvested in the plant to third ratoon crops. The objective of this study was to determine the trends in components of GxE and their implications. The MIXED procedure of Statistical Analysis System (SAS) was used to estimate variance components. Genotype by location interaction was significant for the irrigated and coastal long-cycle programs, indicating the importance of identifying and characterizing sites. Genotype by crop-year interaction was larger and more significant for rain-fed than for irrigated cropping system, indicating the importance of ratooning ability in rain-fed regions. Genotype by location by crop-year interaction was significant (P < 0.01) for yield and sucrose content, highlighting the complexity associated with breeding sugarcane. The coastal long-cycle program was the most complex and generally characterized by large GxE. Separating the coastal hinterland and coastal average potential would be recommended to reduce GxE.

Trends in Broad Sense Heritability and Implications for Sugarcane Breeding in South Africa

Relocation of South African Sugarcane Research Institute (SASRI) rain-fed research stations was due to urban encroachment and to increase representativeness of research farms. The relocation also coincided with the Recoverable Value (RV) payment system in 1998, which penalized growers for low sucrose content. After 12 years of trials, the large data set collected provided an opportunity to evaluate trends and progress. The objective of this study was to determine trends in broad sense heritability (H) over time and evaluate their implications on SASRI breeding strategies. Data were analysed using the mixed procedure of the Statistical Analysis System to estimate variance components used to calculate H. The coastal short cycle and midlands programs produced significant decrease in H for yield and marginal increase for sucrose content. The irrigated and coastal long cycle produced increase in H for yield. The breeding strategies resulting from the shift to RV payment system increased H for yield in irrigated and coastal long cycle probably due to stable populations for irrigated and increased efficiency for coastal long cycle. The coastal short cycle and midlands showed decreasing trends in H for yield probably due to intensive selection for sucrose content on populations with narrow genetic diversity. The H proved to be an effective parameter for evaluating breeding and selection strategies.

Estimation of leaf nitrogen and silicon using hyperspectral remote sensing

The potential to estimate the nutrient status in important agricultural crops such as maize and sugarcane is of significant interest. In South African sugarcane agriculture, just like in global ecosystem, the estimation of Nitrogen (N) and Silicon (Si) is very important. These nutrients are one of the factors influencing the prevalence of the stalk borer Eldana saccharina Walker (Lepidoptera: Pyralidae). Therefore, the researchers aim at estimating leaf N and Si concentration as well as their ratio in sugarcane using hyperspectral remote sensing (spectroradiometry) for monitoring E. saccharina. A hand-held Analytical Spectral Devices (ASD) Field Spec® 3 spectroradiometer was used to take leaf spectral measurements of sugarcane plants from a potted-plant trial taking place under shade house conditions. In this trial, nitrogen and silicon nutrient applications as well as varieties used were known. In addition, watering regimes and artificial infestation of E. saccharina were carefully controlled. The study results indicate that the Red-edge Index (R740/R720) is linearly related to N concentration (R 2 = 0.81, Root Mean Square Error (RMSE) = 0.103) for N37 with the highest correlation coefficient. For Si, the index (R 750 -R 560 )/(R 750 +R 560 ) was linearly related to Si concentration (R 2 = 0.53, RMSE = 0.118) for N25. Finally, the N:Si ratio was linearly correlated to the index (R 1075 -R 730 )/(R 1075 +R 730 ) (R 2 = 0.67, RMSE = 1.508) for N37, hence this index can be used for early detection of E. saccharina damage or for identifying sugarcane that is prone to attack by E. saccharina. It was concluded that hyperspectral remote sensing has potential for use in estimating the N:Si ratio and E. saccharina potential infestations can be monitored rapidly and nondestructively in sugarcane under controlled conditions. It is recommended that an advanced study be conducted in field conditions using airborne and/or spaceborne hyperspectral sensors.

Potential of spectroscopic data sets for sugarcane thrips (Fulmekiola serrata Kobus) damage detection

Sugarcane thrips was detected in South African sugarcane in 2004. Since then it has become widespread in South Africa. The South African Sugarcane Research Institute (SASRI) conducts field surveys to monitor this pest, but this is time intensive and costly. As a first step towards evaluation of remote sensing for thrips monitoring, a preliminary experiment and analysis at leaf level were conducted using a handheld field spectroradiometer covering the 350 to 2500 nm range of the electromagnetic spectrum to detect sugarcane thrips damage. Reflectance spectra of sugarcane leaves with different levels of thrips damage, from two popular varieties (N19 and N12), were measured and statistically analysed using one-way analysis of variance, sensitivity analysis and canonical discriminant analysis. The results of the analyses showed that there were significant differences in spectral reflectance and derived variables used in the study at the different levels of damage. The red edge region of the visible portion gave the highest significant differences and levels of separability among the damage classes. It is hypothesized that this might be associated with chlorophyll and nitrogen deficiencies induced by thrips.

ChemInform Abstract: Desymmetrization of 1,4-Dien-3-ols and Related Compounds via Ueno-Stork Radical Cyclizations.

Desymmetrization of 1,4-dien-3-ols and related compounds via Ueno−Stork radical cyclizations is reported. The stereochemistry of the cyclization is controlled by the acetal center. Excellent stereocontrol at C(4) and C(5) of the newly formed tetrahydrofuran rings is observed. Use of a chiral auxiliary allows the preparation of enantiomerically pure material. The utility of this method has been demonstrated by achieving a short synthesis of (+)-eldanolide, the pheromone of the male African sugarcane stem borer Eldana saccharina.

Sugarcane genetic engineering research in South Africa: From gene discovery to transgene expression

Over the past 15 years, recombinant DNA and in vitro culture technologies have been used in concert at the South African Sugarcane Research Institute (SASRI) to genetically engineer sugarcane. The purpose of such research has been two-fold, viz. to establish proof-of-principle regarding the delivery of novel input and resistance traits to sugarcane and to investigate the genetic basis of sucrose accumulation. Underpinning these goals has been the in-house development of essential genetic resources, including the isolation of appropriate transgenes and gene promoter elements, and the optimisation of transformation and tissue culture technologies. With regard to the latter, emphasis has been placed on the development of tissue culture strategies that minimise the potential for somaclonal variation, while maximising the efficiency of germplasm transformation, selection, regeneration and acclimation. The isolation of promoters to drive high-level and targeted transgene expression, as well as the identification of DNA sequences with the potential to deliver the desired phenotype, have been strongly driven by advances in gene discovery and expression technologies. Early approaches relied on the analysis of Expressed Sequence Tag libraries constructed from sugarcane tissues at different developmental stages or challenged with selected abiotic and biotic stress agents. Subsequent improvements in DNA subtractive hybridisation technologies (e.g. suppression subtractive hybridisation) and gene expression analysis (e.g. Affymetrix® Sugarcane Genome GeneChip) provided new and powerful means for gene and promoter discovery. Reviewed here are the advances in in vitro culture, gene discovery and transgene expression research, which have formed the foundation of the genetic engineering program at SASRI. Also discussed are the opportunities and challenges in these areas of research that are presented by the availability of ultra-high throughput DNA sequencing (e.g. the 454 Sequencing System) for transcriptome analysis and technologies for rapid and accurate profiling of the sugarcane metabolomes.

A DECISION SUPPORT SYSTEM FOR SUGARCANE VARIETY SELECTION IN SOUTH AFRICA BASED ON GENOTYPE-BY-ENVIRONMENT ANALYSES

SUMMARYThe objective of this study was to develop a basic variety selection decision support system (DSS) based on industry legalities, varietal characteristics and structured genotype-by-environment (G × E) analyses. Trial data extracted from a variety trial database at the South African Sugarcane Research Institute (SASRI) were categorized into different regions, harvest ages (12, 18, 24 months) and harvest seasons (early, mid, late season harvests). Restricted maximum likelihood analyses were conducted regionally to determine varietal adaptability to different harvest ages and seasons. Highly significant variety × harvest age and variety × season interactions allowed for the appropriate categorization of varieties. Varietal adaptability to different yield potential conditions was determined using the sites regression technique, and varietal adaptability was interpreted from the slope of the regression curves. The analysed data were used to create simplistic ‘yes/no’ spreadsheets, which were housed within a relational database. A web interface linked to the database allows users to specify characteristics of their production environment. The system then selects appropriate varieties that conform to specified criteria and eliminates non-compliers in a stepwise approach. The system was subsequently validated against expert extension specialist opinion and acceptable performance was observed.

Within-field damage and distribution patterns of the stalk borer, Eldana saccharina (Lepidoptera: Pyralidae), in sugarcane and a comparison with nematode damage

The occurrence of Eldana saccharina (Lepidoptera: Pyralidae) was monitored in grids represented by plots in 12 nematicide trials in South African sugarcane fields. The trials encompassed a total of eight plant cane crops and 22 ratoon crops and were situated within commercial cane fields. Several measurements were made to characterize the damage caused by E. saccharina. These included the number of internodes per stalk, the percentage of internodes damaged and the percentage of stalks damaged. The mapping of E. saccharina infestation in plant crops of sugarcane showed that the borders of the trials were as infested as the centre, indicating invasion from outside the field plus internal spread within the field. Ratoon crops were less infested than plant crops. This could be explained by a shorter ratoon crop cycle and by the fields having areas that were more suitable for the borer than elsewhere. The location of these preferred areas could be predicted from one ratoon crop to the next but was not related to the distribution of the borer in the plant crop. This situation was thought to explain the apparent stabilization of E. saccharina infestation in ratoon cane. Because the borer was found at harvest only in stalks with more than 14 to 16 internodes, it appeared that the oldest shoots, or the shoots with the greatest growth potential, attracted the insect, possibly due to their higher nitrogen content, which would stimulate growth. All the trials were on sandy soil, and crop loss from nematodes was greater than that caused by E. saccharina.

Post-harvest biology of sugarcane

Cutting of the sugarcane stalk at harvest disrupts the physiology of the plant. The altered balance amongst plant functions that results from cutting leads to changes in the composition of the stalk, many of which are undesirable. These negative effects are worsened by increased duration of the period between harvest and sucrose extraction, as well as by high ambient temperature. In addition to physiological changes within the stalk, damage to the stalk during harvesting provides entry points for microbes (bacteria and fungi) that occur naturally in the environment. Many of these microbes grow well in the sucrose-rich stalk, using the sugars as an energy source, while producing metabolic by-products that cause processing problems in the mill and refinery. Post-harvest physiology and microbiology of the sugarcane stalk are currently being studied at the South African Sugarcane Research Institute (SASRI) to determine the effects of harvesting on sucrose and hexose (glucose and fructose) levels, the growth of microbes in the stalk and the appearance of undesirable by-products of microbial metabolism. The information will ultimately be used in the development of mathematical models to quantify and predict the effects of harvest-to-crush delays on stakeholder profitability.

First Report of Maize streak virus Field Infection of Sugarcane in South Africa.

Prior to the introduction of highly resistant sugarcane varieties, Sugarcane streak virus (SSV) caused serious sugar yield losses in southern Africa. Recently, sugarcane plants with streak symptoms have been identified across South Africa. Unlike the characteristic fine stippling and streaking of SSV, the symptoms resembled the broader, elongated chlorotic lesions commonly observed in wild grasses infected with the related Maize streak virus (MSV). Importantly, these symptoms have been reported on a newly released South African sugarcane cultivar, N44 (resistant to SSV). Following a first report from southern KwaZulu-Natal, South Africa in February 2006, a survey in May 2007 identified numerous plants with identical symptoms in fields of cvs. N44, N27, and N36 across the entire South African sugarcane-growing region. Between 0.04 and 1.6% of the plants in infected fields had streak symptoms. Wild grass species with similar streaking symptoms were observed adjacent to one of these fields. Potted stalks collected from infected N44 plants germinated in a glasshouse exhibited streak symptoms within 10 days. Virus genomes were isolated and sequenced from a symptomatic N44 and Urochloa plantaginea plants collected from one of the surveyed fields (1). Phylogenetic analysis determined that while viruses from both plants closely resembled the South African maize-adapted MSV strain, MSV-A4 (>98.5% genome-wide sequence identity), they were only very distantly related to SSV (~65% identity; MSV-Sasri_S: EU152254; MSV-Sasri_G: EU152255). To our knowledge, this is the first confirmed report of maize-adapted MSV variants in sugarcane. In the 1980s, "MSV strains" were serologically identified in sugarcane plants exhibiting streak symptoms in Reunion and Mauritius, but these were not genetically characterized (2,3). There have been no subsequent reports on the impact of such MSV infections on sugarcane cultivation on these islands. Also, at least five MSV strains have now been described, only one of which, MSV-A, causes significant disease in maize and it is unknown which strain was responsible for sugarcane diseases on these islands in the 1980s (2,3). MSV-A infections could have serious implications for the South African sugar industry. Besides yield losses in infected plants due to stunting and reduced photosynthesis, the virus could be considerably more difficult to control than it is in maize because sugarcane is vegetatively propagated and individual plants remain within fields for years rather than months. Moreover, there is a large MSV-A reservoir in maize and other grasses everywhere sugarcane is grown in southern Africa.

South African Sugarcane Research Institute: Embracing biotechnology for crop improvement research

The South African Sugarcane Research Institute (SASRI) is a leading agricultural research institute and the only one of its kind in Africa conducting research into the development of new varieties, improving crop management and farming systems to enhance sugarcane productivity. In addition, effective delivery of new knowledge and technology make a significant contribution to the sustainability of the sugar industry in southern Africa. Variety Improvement and Crop Protection are key focus areas of research that have embraced modern molecular technologies to advance both conventional breeding and integrated control of pests and diseases.