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D. E. Conlong - One of the best experts on this subject based on the ideXlab platform.
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ELDANA Saccharina (LEP: PYRALIDAE) AND ITS PARASITOIDS AT KINYARA SUGAR WORKS, UGANDA
2013Co-Authors: D. E. Conlong, A MugalulaAbstract:Since 1996, regular surveys have been completed for Eldana Saccharina Walker and parasitoids of its different life stages in sugarcane and Cyperus papyrus during visits to Kinyara Sugar Works, Uganda. A complex of dipteran (Tachinidae) and hymenopteran (Braconidae, Ichneumonidae, Bethylidae and Eulophidae) parasitoids have been discovered attacking E. Saccharina infesting C. papyrus. One species of Tachinidae and one species of Ichneumonidae have been recorded from E. Saccharina attacking very old sugarcane on the estate. This paper lists the parasitoids of E. Saccharina found on the estate, and follows the rates of parasitism recorded during visits at different times of the year, and through the years on populations of E. Saccharina in C. papyrus wetlands on the estate. Co-operation between SASEX and Kinyara Sugar Works will benefit both institutions through increased knowledge of pest/parasitoid interactions, and thus facilitate establishing laboratory colonies of parasitoids for introduction into infested sugarcane in both countries
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detection of sugarcane african stalk borer eldana Saccharina walker lepidoptera pyralidae using hyperspectral remote sensing spectroradiometry
Proceedings of the 82nd Annual Congress of the South African Sugar Technologists' Association Durban South Africa 26-28 August 2009., 2009Co-Authors: Tholang Mokhele, Fethi Ahmed, D. E. ConlongAbstract:The South African sugar industry is one of the world’s leading sugarcane producers. The stalk borer Eldana Saccharina has for many years been the most destructive pest in the South African sugar industry and is the most important factor limiting sugarcane productivity. The pest has been monitored using a traditional visual approach whereby a representative sample of stalks is taken from a field and split longitudinally to assess damage and count the number of E. Saccharina. This approach is time-consuming, labour intensive and sometimes biased as, in some instances, only easily accessible areas are surveyed. To investigate a more economical but equally sensitive survey methodology, this paper aims at determining the potential use of hyperspectral remote sensing (spectroradiometry) for identifying sugarcane infested by E. Saccharina. A hand-held 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 fertiliser applications as well as varieties used were known. In addition, watering regimes and artificial infestation of E. Saccharina were carefully controlled. Results illustrated that severe E. Saccharina infestation increased reflectance throughout the whole spectrum range (400-2500 nm). E. Saccharina stalk damage was also linearly related to modified normalized difference vegetation index (mNDVI) using R2025 and R2200 (R 2 =0.69). It was concluded that hyperspectral data has a
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progress of the area wide integrated pest management plan for eldana Saccharina walker lepidoptera pyralidae in the midlands north region of kwazulu natal
Proceedings of the 82nd Annual Congress of the South African Sugar Technologists' Association Durban South Africa 26-28 August 2009., 2009Co-Authors: T M Webster, P G Brenchley, D. E. ConlongAbstract:In 2005, 14 farms in the Midlands North Extension Region were reported with Eldana Saccharina Walker (Lepidoptera: Pyralidae). Currently, a further 29 farms in this region are known to have this pest in their sugarcane. It is thus firmly entrenched in the Midlands North Region (MNR), and is spreading. This 207% increase in known localities over three years in this region is disturbing, and highlights the urgent need for growers to implement the IPM plan presented in 2005, on an area wide basis. This paper demonstrates the increased occurrence and spread of E. Saccharina in ecozones 1-6, 8, 10 and 11 since 2005. Using already known ecological data on E. Saccharina, soil characteristics and climatic forecasts, it is evident that ecozone 7 is the next likely area to suffer an increase in E. Saccharina numbers, should growers continue with the slow implementation of the Integrated Pest Management (IPM) plan and the Environmental Management System (EMS), which are aimed at minimising the threat of E. Saccharina in their areas.
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Response of Goniozus indicus (Hymenoptera: Bethylidae) to sugarcane and Cyperus papyrus volatiles.
2006Co-Authors: J. M. Smith, D. E. Conlong, M. Byrne, B. FrerotAbstract:Gas chromatography revealed different volatile emissions from uninfested and infested sugarcane, and uninfested Cyperus papyrus L, when compared with infested C. papyrus. In addition, Goniozus indicus Ashmead showed an attraction to samples containing frass from Eldana Saccharina Walker that had fed on C. papyrus, and no attraction to samples containing frass from E. Saccharina that had fed on sugarcane. These results indicate that chemical cues are important for G. indicus to locate a host habitat, and that the cues may be missing from E. Saccharina infested sugarcane.
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HABITAT MANAGEMENT USING MELINIS MINUTIFLORA (POACEAE) TO DECREASE THE INFESTATION OF SUGARCANE BY ELDANA Saccharina (LEPIDOPTERA: PYRALIDAE)
2006Co-Authors: A. L. Barker, D. E. Conlong, M. J. ByrneAbstract:In field trials planted in the Midlands North and Gingindlovu areas, Melinis minutiflora Beauv. was intercropped in various ways with sugarcane in fields bordered by Cyperus dives C.B. Cl. to determine whether the presence of this grass reduced Eldana Saccharina Walker numbers and infestation levels in sugarcane. Results showed E. Saccharina populations were decreased by up to 50% and E. Saccharina damage was reduced by up to 57% when compared with control fields. In addition, no competition was recorded between M. minutiflora and adjacent sugarcane rows in terms of sugarcane yield loss. Where M. minutiflora was planted along field margins, weed biomass was reduced by up to 79%. These results are discussed in the context of E. Saccharina population management, field margin weed management and potential economic benefits accrued from using this approach.
Paul J Harrison - One of the best experts on this subject based on the ideXlab platform.
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ammonium and nitrate uptake by laminaria Saccharina and nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria Saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. Saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. Saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. Saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. Saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. Saccharina and Nereocystis. Unlike L. Saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p <0.05). Both L. Saccharina and Nereocystis would be suitable for integrated cultivation of salmon/kelp.
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Ammonium and nitrate uptake by Laminaria Saccharina and Nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria Saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. Saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. Saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. Saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. Saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. Saccharina and Nereocystis. Unlike L. Saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p
Andrew Mitchell - One of the best experts on this subject based on the ideXlab platform.
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Status of Eldana Saccharina (Lepidoptera: Pyralidae), its host plants and natural enemies in Ethiopia.
Bulletin of entomological research, 2006Co-Authors: Y Assefa, Des Conlong, Andrew MitchellAbstract:Surveys for sugarcane stem borers were undertaken in Ethiopia to determine the prevalence and distribution of these and their natural enemies in crops and indigenous host plants. Eldana Saccharina Walker was not recovered from sugarcane, but was present in three indigenous wetland sedges, Cyperus papyrus, C. fastigiatus and C. dives in the southern, central and northern part of the country. The latter indigenous host plant was present in waterways adjacent to sugarcane on the commercial sugar estates. The tachinids Schembria eldanae Barraclough and Actia sp. were common parasitoids of E. Saccharina larvae in these indigenous sedges. The braconid Dolichogenidea sp. was recovered from E. Saccharina larvae in C. dives. Pathogens comprising Beauveria bassiana, Bacillus thuringiensis and Entomophthora sp., were found to be important mortality factors of E. Saccharina larvae in the indigenous sedges. The occurrence of E. Saccharina in Ethiopia is reported for the first time, and the host plant preferences of the borer and its indigenous natural enemies found during the surveys are recorded. In addition, its potential threat to sugarcane production in Ethiopia is discussed.
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MITOCHONDRIAL DNA SEQUENCE VARIATION AMONG POPULATIONS OF SUGARCANE BORER ELDANA Saccharina WALKER (LEPIDOPTERA: PYRALIDAE)
2005Co-Authors: Yoseph Assefa, D. E. Conlong, Andrew MitchellAbstract:Studies on Eldana Saccharina have shown that populations from western Africa have distinct behavioural differences when compared with populations from eastern and southern Africa. In addition, the parasitoid guilds attacking these populations in the different regions are markedly different. The parallel geographical variation in these patterns between several widespread populations of E. Saccharina evoked the hypothesis of diversification. To evaluate this hypothesis, a molecular analysis of the Cytochrome Oxidase c subunit I (COI) region of the mitochondrial DNA was conducted on populations of E. Saccharina from various parts of Africa. Results of the current study reveal the presence of genetic variation in E. Saccharina populations, which is related to geographical distribution.
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GENETIC DIFFERENTIATION IN ELDANA Saccharina (LEPIDOPTERA: PYRALIDAE): EVIDENCE FROM THE MITOCHONDRIAL CYTOCHROME OXIDASE I AND II GENES
2002Co-Authors: H King, D. E. Conlong, Andrew MitchellAbstract:The sugarcane stemborer Eldana Saccharina is an indigenous African moth found throughout much of subsaharan Africa. Previous research has revealed ecological differences among geographical populations, raising the possibility that E. Saccharina may consist of different biotypes. As a first step towards evaluating this hypothesis, E. Saccharina populations from across Africa were surveyed for mitochondrial DNA variation. The complete coding regions of the mitochondrial cytochrome c oxidase I (COI) and COII genes were sequenced for three individuals from Benin, Uganda and South Africa, and a fragment of COI was sequenced for additional specimens representing a wider geographical range. The levels of sequence divergence found in comparisons between the northern E. Saccharina populations of Benin, Uganda and Cameroon and those of southern Africa were at least as high as those between recognized biotypes in other species. This suggests potentially limited gene flow among E. Saccharina populations that merits further investigation.
Rs Rutherford - One of the best experts on this subject based on the ideXlab platform.
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Eldana Saccharina (Lepidoptera: Pyralidae) Resistance in Sugarcane (Saccharum sp.): Effects of Fusarium spp., Stalk Rind, Fibre and Nitrogen Content
African Entomology, 2014Co-Authors: Tendekai Mahlanza, Rs Rutherford, S. J. Snyman, M.p. WattAbstract:Sugarcane cultivar resistance to Eldana Saccharina is the best strategy to control the stalk borer. The present study aimed to establish the influence of stalk rind hardness, fibre and nitrogen content, and the effect Fusarium species associated with E. Saccharina infestation, on borer damage and performance in different sugarcane cultivars. In two glasshouse trials, larvae were inoculated into 7-month-old stalks of seven cultivars with different E. Saccharina resistance ratings via wounds created in the rind. In one of the trials, E. Saccharina-beneficial fungal strain Fusarium pseudonygamai SC17 and E. Saccharina antagonistic F. sacchari PNG40 were inoculated into the stalk of N41 and NCo376 three weeks before larval inoculation. Rind hardness and fibre content were higher in resistant cultivars and mature stalk parts, whilst nitrogen content was lower in these genotypes and in older tissues. However, E. Saccharina survival, damage and growth indicators were not entirely consistent with known resistance...
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fusarium species causing pokkah boeng and their effect on eldana Saccharina walker lepidoptera pyralidae
83rd Annual Congress of the South African Sugar Technologists' Association Durban South Africa 25-27 August 2010., 2010Co-Authors: P Govender, S A Mcfarlane, Rs RutherfordAbstract:Pokkah boeng is a fungal disease that can cause serious yield losses in susceptible varieties. Pokkah boeng is caused by Fusarium, but there is some debate regarding the species involved. Previous research has revealed that some Fusarium species isolated from sugarcane could benefit the development of the stalk borer, Eldana Saccharina, a serious pest of sugarcane in South Africa. The aim of this research was to isolate and identify the causal organism of pokkah boeng and to determine the effect of the isolates on the development of E. Saccharina. Eight representative isolates were inoculated into pokkah boeng susceptible varieties N34 and N41. Typical pokkah boeng symptoms were evident after three weeks. Isolates inoculated into the pot trial and the isolates obtained from inoculated, symptomatic plants were identified as F. sacchari, F. proliferatum and F. andiyazi. The isolates were included in E. Saccharina diet and olfactory choice assays. When compared to controls in the dietary inclusion assays, three isolates were considered to be antagonistic (two identified as F. andiyazi and one as F. proliferatum) to E. Saccharina, with the mean mass of surviving larvae being significantly lower than the controls. In this study, no isolates resulted in significantly greater larval mass than the controls. Results from the olfactory choice assays suggested that all isolates were attractive to E. Saccharina, with significantly more larvae feeding on inoculated maize kernels than the uninoculated controls.
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interactions between fusarium species from sugarcane and the stalk borer eldana Saccharina lepidoptera pyralidae
Annals of Applied Biology, 2009Co-Authors: S A Mcfarlane, P Govender, Rs RutherfordAbstract:In this study, beneficial relationships between Fusarium species in sugarcane and the stalk borer, Eldana Saccharina (Lepidoptera: Pyralidae) were demonstrated in vitro. In addition, Fusarium species with antagonistic properties were found to inhabit sugarcane. Attenuated Fusarium isolates from sugarcane stalks collected across the South African sugar industry were incorporated into diet formulated to mass rear E. Saccharina. Of the over 200 Fusarium isolates obtained, 10 that significantly improved the survival and development of E. Saccharina larvae and considered to be beneficial were selected for further study, as were 10 that were detrimental or antagonistic to the stalk borer. Twelve of the selected isolates were identified as F. sacchari by direct sequencing of translation elongation factor-1α fragments, eight of which resulted in reduced numbers of surviving larvae and significantly lower larval masses. F. proliferatum isolates resulted in increased survival and mass of E. Saccharina and three of the five isolates assigned to the F. pseudonygamai group enhanced E. Saccharina development. Results from olfactory choice experiments suggested the production of attractive and repellent metabolites by certain isolates. Findings from this study may offer additional or alternative strategies for managing E. Saccharina infestation of sugarcane.
François-régis Goebel - One of the best experts on this subject based on the ideXlab platform.
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MONITORING ELDANA Saccharina AND OTHER ARTHROPOD PESTS IN SOUTH AFRICAN SUGARCANE By
2016Co-Authors: Mickael J. Way, François-régis GoebelAbstract:Each year from January to December, field surveys are conducted throughout South African sugarcane primarily for the key pest, Eldana Saccharina Walker (Lepidoptera: Pyralidae). Monitoring allows detection of excessive larval infestations for early harvesting to assist in reducing populations on an area-wide scale, selection of suitable carryover fields and inspection of seed cane. During surveying, known arthropod crop spoilers are recorded and staff remain vigilant for possible new arthropod incursions. These data provide information about regional infestations of E. Saccharina in the industry. Furthermore, related agronomic information is recorded thus providing evidence to support the value of current management tactics employed to reduce the adverse affects of E. Saccharina. Additional applications for the E. Saccharina records in the database are being researched such as investigating infestations recorded in different varieties, mapping infestations, and for the production of region loss estimates
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Monitoring Eldana Saccharina and other arthropod pests in South African sugarcane
2007Co-Authors: Mickael J. Way, François-régis GoebelAbstract:Each year from January to December, field surveys are conducted throughout South African sugarcane primarily for the key pest, Eldana Saccharina Walker (Lepidoptera: Pyralidae). Monitoring allows detection of excessive larval infestations for early harvesting to assist in reducing populations on an area-wide scale, selection of suitable carryover fields and inspection of seed cane. During surveying, known arthropod crop spoilers are recorded and staff remain vigilant for possible new arthropod incursions. These data provide information about regional infestations of E. Saccharina in the industry. Furthermore, related agronomic information is recorded thus providing evidence to support the value of current management tactics employed to reduce the adverse affects of E. Saccharina. Additional applications for the E. Saccharina records in the database are being researched such as investigating infestations recorded in different varieties, mapping infestations, and for the production of region loss estimates. (Resume d'auteur)
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silicon and water stress synergy in resistance of sugarcane cultivars to the stalk borer eldana Saccharina lepidoptera pyralidae
International Sugar Journal, 2007Co-Authors: Olivia L Kvedaras, M. G. Keeping, François-régis Goebel, Marcus J ByrneAbstract:Silicon (Si) improves plant resistance to insect attack and may also enhance tolerance of water stress. The objective of this study was to evaluate whether Si-mediated resistance of sugarcane to the borer Eldana Saccharina Walker (Lepidoptera: Pyralidae) is enhanced by water stress. Sugarcane cultivars, two resistant to E. Saccharina (N21, N33) and two susceptible (N26, N11) were grown in a pot trial, in Si deficient river sand with (Si+) and without (Si-) calcium silicate. To induce water stress, irrigation to half of the trial was reduced prior to inoculation with E. Saccharina eggs, and harvested 66 days later. Stressed and non-stressed plants of the same cultivar did not differ significantly in Si content. However, Si+ plants exhibited increased resistance to E. Saccharina attack. In Si+ cane, E. Saccharina larval survival and biomass was lower than in Si- cane, significantly so for stressed, susceptible cultivars N26 and N11, and for larval mass in non-stressed N26. Stalk damage was reduced in Si+ cane, significantly so for the stressed, susceptible cultivars N26 and N11, and non-stressed N26. This study showed that Si provides greater protection against E. Saccharina attack in susceptible, water-stressed sugarcane than in non-stressed cane and/or resistant cultivars. (Resume d'auteur)
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The value of regional pest and disease team data in determining the impact of Eldana Saccharina (Lipidoptera : Pyralidae) on the south african sugarcane industry
2003Co-Authors: Mickael J. Way, François-régis GoebelAbstract:Eldana Saccharina Walker (Lepidoptera: Pyralidae) is the major pest of the South African sugarcane industry. Pest and Disease field teams based in each mill area of the industry monitor population levels and assess levels of damage in different parts of the industry. This information is used during the season to detect areas of high infestation that can be harvested to help reduce the detrimental effects of this pest. The survey data from 3 years of routine monitoring were summarized to show: (1) long-term population trends; (2) differences in cultivar susceptibility; (3) crop-age influences on E. Saccharina. Additionally, these data provide baseline E. Saccharina levels in different geographical localities within the industry. Generally, E. Saccharina infestations are more serious in rain-fed areas than in irrigated sugarcane, some sugarcane cultivars are more susceptible than others, and infestations are usually higher in older crops. This paper illustrates the important points arising from the analysis of these survey data, and discusses the main factors that are known to influence infestation and damage levels of this pest in this industry. (Authors' abstract)
