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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The development of a putative microbial product for use in crop production /

Gumede, Halalisani. January 2008 (has links)
Thesis (M.Sc. (Biochemistry, Microbiology & Biotechnology)) - Rhodes University, 2008.
62

Establishment of blackberries and detection and management of raspberry crown borer

Heard, Edward, January 2006 (has links)
Thesis (M.S.)--Mississippi State University. Department of Plant and Soil Sciences. / Title from title screen. Includes bibliographical references.
63

Studies on the use of biocontrol agents and soluble silicon against powdery mildew of zucchini and zinnia /

Tesfagiorgis, Habtom Butsuamlak. January 2008 (has links)
Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2008. / Full text also available online. Scroll down for electronic link.
64

Interactions of Beauveria bassiana with the American dog tick, Dermacentor variabilis (Say), and the lone star tick, Amblyomma americanum L.

Cradock, Kenwyn R., January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 126 p.; also includes graphics (some col.). Includes bibliographical references (p. 96-107). Available online via OhioLINK's ETD Center
65

Himenópteros parasitoides de Pseudococcidae (Hemiptera: Coccomorpha) no estado de São Paulo /

Siqueira, Matheus Alves de. January 2018 (has links)
Orientador: Nilza Maria Martinelli / Coorientadora: Ana Lúcia Benfatti Gonzalez Peronti / Banca: Odair Aparecido Fernandes / Banca: Valmir Antonio Costa / Resumo: A família Pseudococcidae é a segunda maior da Infraordem Coccomorpha, com cerca de 2000 espécies descritas. No Brasil, conhecidas popularmente como cochonilhas-farinhentas, compreendem a terceira maior família, com 77 espécies registradas, distribuídas em 22 gêneros. Destas, 32 espécies são conhecidas para o estado de São Paulo, sendo 30% polífagas e de origem exótica, infestando plantas de importância agrícola. O controle biológico é uma alternativa, e dentre os inimigos naturais os himenópteros parasitoides vêm sendo muito utilizados. O objetivo deste trabalho foi inventariar os micro-himenópteros parasitoides de 11 espécies de pseudococcídeos pragas, primarias ou secundarias, de várias culturas e plantas ornamentais no estado de São Paulo, como café, citros, pinha, goiabeira, entre outros, relacionando estes com seu hospedeiro, origem e distribuição geográfica. Os levantamentos dos himenópteros parasitoides foram realizados entre agosto de 2016 e agosto de 2017, de forma aleatória, em áreas rural e urbana de cinco municípios do estado São Paulo: Jales, Ribeirão Preto, Jaboticabal, São Carlos e Campinas. As espécies de pseudococcídeos amostrados para obtenção dos parasitoides foram: Dysmicoccus brevipes (Cockerell, 1893), Ferrisia virgata (Cockerell, 1893), Leptococcus capixaba Kondo, 2005, Leptococcus minutus (Hempel, 1932), Maconelicoccus hirsutus (Green, 1908), Nipaecoccus nipae (Maskell, 1893), Phenacoccus solenopsis Tinsley, 1898, Planococcus citri (Risso, 181... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Pseudococcidae family is the second largest from the Coccomorpha Infraorder, with about 2000 described species. In Brazil, popularly known as mealybugs, it comprised the third largest family, with 77 species registered, distributed in 22 genera. From these, 32 species are known to the state of São Paulo, being 30% polyphagous from exotic origin, infesting plants of agricultural importance. Biological control is an alternative and among natural enemies, parasitoid Hymenoptera are being widely used. The objective of this work was to inventory the parasitoid microhymenoptera from 11 mealybug pest species, primary or secondary, from various crops and ornamental plants in the state of São Paulo, such as coffee, citrus, sugar-apple, guavas and others, relating these to their host, origin and geographical distribution. The parasitoid hymenopteran surveys were carried out between August 2016 and August 2017, in a random way, in rural and urban areas from five municipalities in the state of São Paulo: Jales, Ribeirão Preto, Jaboticabal, São Carlos and Campinas. The Pseudococcidae species sampled to obtain parasitoids were: Dysmicoccus brevipes (Cockerell, 1893), Ferrisia virgata (Cockerell, 1893), Leptococcus capixaba Kondo, 2005, Leptococcus minutus (Hempel, 1932), Maconelicoccus hirsutus (Green, 1908), Nipaecoccus nipae (Maskell, 1893), Phenacoccus solenopsis Tinsley, 1898, Planococcus citri (Risso, 1813), Planococcus minor (Maskell, 1897), Pseudococcus cryptus (Hempel... (Complete abstract click electronic access below) / Mestre
66

The influence of cabbage cultivars on the fitness of Plutella xylostella (Linnaeus 1758) (Lepidoptera: Plutellidae) and its biological control agent Cotesia vestalis (Haliday 1834) (Hymenoptera: Braconidae)

Nethononda, Phophi Dzivhuluwani 20 April 2016 (has links)
The diamondback moth, Plutella xylostella (Linnaeus 1758.) (Lepidoptera: Plutellidae), is a major insect pest of Brassica crops in many parts of the world leading to economic losses amounting to an estimated US$ 4-5 billion. Although parasitoids (biological control agents) play a major role in suppressing the pest populations during November – May in South Africa, the pest reaches outbreak status during September and October due to low impact of parasitoids, which has necessitated regular application of insecticides. However, insecticide applications have often resulted in the pest developing resistance, and when coupled with the negative effects of several insecticides on parasitoids, integration of the two pest control strategies for effective management of P. xylostella population density has been difficult to achieve. One approach that has received little attention is integration of host plant resistance (bottom-up effect) and biological control (top-down effect) for effective management of P. xylostella. However, the interaction between host plants, the insect pest, and parasitoids is not simple and straight forward, as strong negative impact of host plants on fitness of the insect pest can be cascaded up the food chain and have a negative impact on a given parasitoid, which in turn may reduce the desired complementary effect between the two pest control strategies. To identify optimal interactions between cabbage (Brassica oleracea L. var. capitata, Brassicaceae), P. xylostella and its larval parasitoid Cotesia vestalis (Haliday 1834) (Hymenoptera: Braconidae), this study investigated (i) the effects of seven cabbage cultivars (Empowa, Hollywood F1, Megaton, Leano, Menzania, Beverley Hills and Karabo) on fitness parameters (survival, developmental time, pupal weights, longevity without food and oviposition rates) of P. xylostella; (ii) the influence of the same host plant cultivars on fitness parameters (developmental time, pupal weights, longevity xi without food, fecundity, emergence rate and sex ratio) of C. vestalis. Furthermore, net reproductive rates and the intrinsic rates of natural increase were calculated for C. vestalis that emerged from hosts fed on each of the cultivars. All experiments were conducted in climate-controlled laboratory rooms maintained at 22 ± 1 ºC (mean ± S.D.), 60 ± 5 % RH and 16L: 8D photoperiod. Under the no choice test, overall survival of P. xylostella immature stages was highest on Karabo (67.26%) and lowest on Megaton (44.92%). The larval and pupal developmental period, and generation time was prolonged on Empowa (18.48 days), Karabo (14.64 days) and Beverly Hills (17.48 days), while developmental period on Hollywood F1 (13.79 days) was shortest. Male and female P. xylostella pupal weights were lighter from larvae that fed on Megaton (4.13 and 4.65 mg), Menzania (4.53 and 4.91 mg), and Hollywood F1 (4.11 and 5.08 mg), whereas pupal weights from Karabo (6.0 and 6.82 mg) were the heaviest. Unfed female moths originally reared on Beverley Hills had the highest longevity (5.05 days), whereas those reared on Leano (3.54 days) and Megaton (3.89 days) had the shortest life span. Under the choice-test, P. xylostella moth laid significantly more eggs on Empowa (48.8%) and Hollywood F1 (45.6%) and least on Menzania (11.8%) and Leano (10.6%). Megaton was more resistant to P. xylostella due to lower survival rates of immature stages, lower pupal weights and moth longevity. The generation time of C. vestalis was shortest on Karabo (10.10 days) and Leano (10.38 days), and longest on Megaton (12.57 days) and Empowa (12.80 days). The highest pupal weight of C. vestalis was obtained from parasitoids reared from P. xylostella fed Menzania (5.4 mg), Megaton (5.25 mg) and Beverly Hills (4.85 mg) and the lightest on Karabo (3.8 mg). Parasitoids reared on larvae that fed on Hollywood F1 lived the longest (2.28 days) followed by Menzania (1.94 days) and Beverly Hills (1.8 days), whereas those whose hosts fed on Leano had shortest life span (0.83 days). Despite the parasitoids from Megaton hosts being heavier, their fecundity and number of female progeny per female (16.87 and 3.60, respectively) were lowest. Cotesia vestalis fecundity and daughters produced per female were highest on hosts fed on Menzania (38.00 and 9.13, respectively) and Beverly Hills (32.87 and 9.07, respectively). As a consequence, the net reproductive rate (R0) and intrinsic rate of increase (r) were higher on Menzania (7.87 and 0.58, respectively) and Beverly Hills (8.29 and 0.62, respectively). As survival and overall fitness of P. xylostella was lower on Megaton, this cultivar can play a major role in restricting population growth of this pest and thus generational number of eggs deposited on it during September and October. However, this strong bottom-up effect of Megaton on P. xylostella was cascaded up the food chain, as overall fitness of C. vestalis was lower on hosts developing on it. In contrast, the overall fitness of C. vestalis was higher on hosts that developed on Menzania and Beverly Hills. As these cultivars showed potential to sustain population density of C. vestalis at higher levels, it is also assumed that the period required for the parasitoid to reach the critical density to suppress the host population at a lower average density will be reached quicker than on other cultivars. Thus, their cultivation may improve biological control of P. xylostella during November–May in South Africa / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
67

Hábito alimentar e morfologia do aparelho digestivo de espécies de Carabidae (Insecta: Coleoptera) associados a plantas herbáceas e ao algodoeiro colorido

Matta, Danilo Henrique da [UNESP] 27 February 2014 (has links) (PDF)
Made available in DSpace on 2014-11-10T11:09:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-27Bitstream added on 2014-11-10T11:58:13Z : No. of bitstreams: 1 000793362.pdf: 2171550 bytes, checksum: cc9265ec01ac15bf4f3b278d742c1e9a (MD5) / Os besouros Carabidae (Coleoptera) apresentam grande importância para a agricultura como inimigos naturais de insetos pragas. No entanto, pouco se conhece sobre hábitos alimentares desses besouros. O presente trabalho visou verificar a ocorrência e o hábito alimentar de espécies de carabídeos associadas a plantas herbáceas floríferas nos diferentes Períodos fenológicos do algodoeiro colorido. O conteúdo alimentar foi avaliado em espécies presentes em cultura de algodoeiro colorido, Gossypium hirsutum L. raça latifolium Hutch., cultivar BRS verde, herbáceo, adjacente de plantas espontâneas e das plantas herbáceas floríferas (PHF) Lobularia maritima (L.) (Brassicaceae), Tagetes erecta L. (Asteraceae), Fagopyrum esculentum Moench (Polygonaceae). Algumas espécies de carabídeos ocorreram em diferentes Períodos fenológicos do algodoeiro e o número mais elevado de indivíduos verificou-se no período reprodutivo do algodoeiro. Os resultados obtidos no aparelho digestivo das espécies de carabídeos mostram que esses insetos podem se alimentar de vários tipos de conteúdo alimentar, relacionados com artrópodes e vegetais associados aos canteiros de PHF, nos diferentes períodos fenológicos do algodoeiro, podendo ser considerados predadores polífagos, e a morfologia do aparelho digestivo das nove espécies de carabídeos mostraram padrões de estruturas adaptadas para o tipo de dieta consumida por essas espécies / The Carabidae beetles (Coleoptera) have great importance to agriculture as natural enemies of insect pests. However, little is known about the content of these beetles feed. This study aimed to assess the occurrence and feeding habits of Carabid species associated with herbaceous plants (PHF) in different growth periods of coloured cotton. The food contents was evaluated in species that occurred in coloured cotton, Gossypium hirsutum L. latifolium Hutch., variety BRS green, herbaceous cotton, adjacent weeds and PHF Lobularia maritima (L.), Tagetes erecta L., Fagopyrum esculentum Moench. Some species of Carabid beetles occurred at different cotton growth periods and the highest number of individuals was found in the cotton reproductive stage. The results showed many types of feed contents ingested by the Carabidae beetles gut tract, like arthropods and vegetable associated with PHF in different growth periods of cotton and can be considered polyphagous predators. The gut tract morphology showed that nine species of Carabid beetles showed standards structures adapted to the type of diet ingested
68

Hábito alimentar e morfologia do aparelho digestivo de espécies de Carabidae (Insecta: Coleoptera) associados a plantas herbáceas e ao algodoeiro colorido /

Matta, Danilo Henrique da. January 2014 (has links)
Orientador: Francisco Jorge Cividanes / Banca: Antonio Carlos Busoli / Banca: Sergio Ide / Resumo: Os besouros Carabidae (Coleoptera) apresentam grande importância para a agricultura como inimigos naturais de insetos pragas. No entanto, pouco se conhece sobre hábitos alimentares desses besouros. O presente trabalho visou verificar a ocorrência e o hábito alimentar de espécies de carabídeos associadas a plantas herbáceas floríferas nos diferentes Períodos fenológicos do algodoeiro colorido. O conteúdo alimentar foi avaliado em espécies presentes em cultura de algodoeiro colorido, Gossypium hirsutum L. raça latifolium Hutch., cultivar BRS verde, herbáceo, adjacente de plantas espontâneas e das plantas herbáceas floríferas (PHF) Lobularia maritima (L.) (Brassicaceae), Tagetes erecta L. (Asteraceae), Fagopyrum esculentum Moench (Polygonaceae). Algumas espécies de carabídeos ocorreram em diferentes Períodos fenológicos do algodoeiro e o número mais elevado de indivíduos verificou-se no período reprodutivo do algodoeiro. Os resultados obtidos no aparelho digestivo das espécies de carabídeos mostram que esses insetos podem se alimentar de vários tipos de conteúdo alimentar, relacionados com artrópodes e vegetais associados aos canteiros de PHF, nos diferentes períodos fenológicos do algodoeiro, podendo ser considerados predadores polífagos, e a morfologia do aparelho digestivo das nove espécies de carabídeos mostraram padrões de estruturas adaptadas para o tipo de dieta consumida por essas espécies / Abstract: The Carabidae beetles (Coleoptera) have great importance to agriculture as natural enemies of insect pests. However, little is known about the content of these beetles feed. This study aimed to assess the occurrence and feeding habits of Carabid species associated with herbaceous plants (PHF) in different growth periods of coloured cotton. The food contents was evaluated in species that occurred in coloured cotton, Gossypium hirsutum L. latifolium Hutch., variety BRS green, herbaceous cotton, adjacent weeds and PHF Lobularia maritima (L.), Tagetes erecta L., Fagopyrum esculentum Moench. Some species of Carabid beetles occurred at different cotton growth periods and the highest number of individuals was found in the cotton reproductive stage. The results showed many types of feed contents ingested by the Carabidae beetles gut tract, like arthropods and vegetable associated with PHF in different growth periods of cotton and can be considered polyphagous predators. The gut tract morphology showed that nine species of Carabid beetles showed standards structures adapted to the type of diet ingested / Mestre
69

The effect of temperature on the feeding and development of Neochetina eichhorniae weevil larvae on water hyacinth (Eichhornia crassipes)

Bokotomba, Ndongo Fyfy January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, March 2017. / Water hyacinth (Eichhornia crassipes) is an example of an alien invasive plant, threatening ecosystems around the world. Taking into consideration all the negative impacts caused by the proliferation of water hyacinth, many control measures have been implemented to manage this weed. These include mechanical control, chemical control and biological control. But in recent years, the focus has shifted towards natural enemies for control (biological control) of water hyacinth because they have many advantages for environmental safety. However, in South Africa, success is limited in most parts of the country. Factors affecting the success of biological control of water hyacinth in South Africa have been attributed in part to weather conditions. Therefore, further studies and other strategies are needed to reinforce the biological control of water hyacinth. This is why this research investigated the influences of temperature on Neochetina eichhorniae larvae feeding and development on water hyacinth, to contribute to the future management of water hyacinth biological control. To measure the effect of temperature on the feeding and development of Neochetina eichhorniae larva, experiments were conducted at four fixed temperatures (15 °C, 20 °C, 25 °C, and 30 °C). Larval feeding is expected to be greater and the development faster at warm temperatures compared with cold temperatures. The results of this study confirmed that, both feeding and larval development increased with an increase in temperature. The highest larval feeding damage was recorded at 30°C and the lowest at 15°C. Similar to the feeding of larvae, warmer temperatures were more favourable to the growth of larvae than cold temperatures; all larvae found at 30°C were in their third instars (with 0.72 mm being the biggest headwidth found) while all larvae at 15°C were in the first instars (with 0.28 mm being the smallest headwidth found). Even if the optimal temperature for larval performance took place at 30 °C (with a high amount of biomass removal), it was at 25 °C that the larvae had a larger effect on the growth of water hyacinth. Larval feeding damage reduced the growth of water hyacinth by 30 % at 25 °C and only affected 24 % of water hyacinth growth at iv 30 °C. Therefore, for the biocontrol of water hyacinth, the ideal temperature to slow the progression of the weed will be recommended at between 25- 30 °C. / LG2017
70

Antimicrobial lipopeptide production by Bacillus spp. for post-harvest biocontrol

Pretorius, Danielle 12 1900 (has links)
Thesis (MEng) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: As overpopulation threatens the world’s ability to feed itself, food has become an invaluable resource. Unfortunately, almost a third of the food produced for human consumption is lost annually. Pests including insects, phytopathogens and weeds are responsible for more than a third of the annual major crop losses suffered around the world. The majority of current post-harvest control strategies employ synthetic agents. These compounds, however, have been found to be detrimental to the environment as well as human health, which has led researchers to investigate alternative strategies. Biocontrol agents are environmentally compatible, have a lower toxicity and are biodegradable, making them an attractive alternative to the synthetic control agents. The lipopeptides produced by Bacillus spp. in particular, have shown great potential as biocontrol agents against various post-harvest phytopathogens. Most biocontrol strategies apply the biocontrol organism, for example Bacillus, directly, whereas this study focused on the use of the lipopeptide itself as an antifungal agent. This is advantageous as the lipopeptides are less sensitive to their surroundings, such as temperature and pH, compared to living organisms, allowing for the production of a standardized product. This study investigated the production of the Bacillus lipopeptides surfactin, fengycin and iturin under controlled batch conditions. Parameters increasing lipopeptide production were quantified, focussing on antifungal lipopeptides (iturin and fengycin), and lipopeptide production was optimized. Experiments were performed in a fully instrumented 1.3 L bench-top bioreactor and lipopeptide analyses were performed via high pressure liquid chromatography (HPLC) and liquid chromatography-mass spectroscopy (LC-MS). After screening four Bacillus spp., Bacillus amyloliquefaciens DSM 23117 was found to be the best antifungal candidate. This was based on it outperforming other candidates in terms of maximum antifungals produced, Yp/x,antifungals (yield per cells), and antifungal productivity. Nitrate, in the form of NH4NO3, was critical for lipopeptide production and an optimum concentration was observed above which the CDW (cell dry weight) no longer increased significantly and both μmax (maximum specific growth rate, h-1) and lipopeptide production decreased. For μmax, the optimum NH3NO4 concentration was 10 g/L and for lipopeptides it was 8 g/L. At these respective NH4NO3 concentrations μmax = 0.58 (h-1), the maximum antifungals (fengycin and iturin) were 285.7 mAU*min and the maximum surfactin concentration was 302 mg/L. The lipopeptides produced by B. amyloliquefaciens, the antifungals (fengycin and iturin) and surfactin, are secondary metabolites, regardless of the optimization treatment, i.e. increased NH4NO3 concentrations. Using 30% enriched air extended the nitrate utilization period, suggesting that when increasing supply concentration, more oxygen was available to act as electron acceptors, allowing nitrate to be used for lipopeptide production. The number of iturin and fengycin homologues generally increased with an increase in nitrate concentration. This suggested that process conditions, such as nitrate concentration, can be used to manipulate homologue ratios, allowing for the possibility to tailor-make biocontrol-agent upstream, during the production process, and possibly increase the efficacy of the biocontrol strategy. The lipopeptides produced by B. amyloliquefaciens showed complete inhibition against Botryotinia fuckeliana and diminished the growth capabilities of Botrytis cinerea. No inhibition was observed against Penicillium digitatum. These results indicate potential of the biocontrol strategy, although scale-up and fed-batch studies are recommended, especially when considering commercial implementation. Studies regarding the lipopeptide application method, i.e. a single application or multiple applications, should also be investigated as this will influence the efficacy of the lipopeptides against the target organisms. / AFRIKKANSE OPSOMMING: Met oorbevolking wat die wêreld se vermoë om die groeiende bevolking te onderhou belemmer, het dit noodsaaklik geword om huidige voedselbronne te beskerm. Daar word beraam dat een derde van die voedsel wat wêreldwyd geproduseer word vir menslike verbruik verlore gaan elke jaar. Verder is insekte, plantpatogene en onkruide verantwoordelik vir meer as ‘n derde van die verliese rakend jaarlikse oeste. Meeste bestaande na-oes beheermetodes maak gebruik van sintetiese stowwe. Ongelukkig kan hierdie verbindings nadelig wees vir die omgewing sowel as menlike gesondheid. Navorsers het hulsef dus toespits daarop om alternatiewe beheermetodes te ondersoek. Bio-beheermetodes is omgewingsvriendelik sowel as bio-afbreekbaar, wat hulle ideale alternatiewe maak vir die sintetiese stowwe. Bacillus spp. lipopeptiede het veral hoë potensiaal getoon as bio-beheermiddels teen verskeie na-oes plantsiektes. Meeste bio-beheermetodes wend die biobeheer organisme, soos Bacillus, direk aan, waar hierdie studie op die gebruik van lipopeptiede as ‘n beheermiddel gefokus het. Die voordeel is dat lipopeptidiede minder sensitief is vir hul omgewings, soos temperatuur en pH, i.v.m. organismes en die moontlikheid bied van ‘n gestandardiseerde produk. Hierdie studie het die produksie van spesifieke Bacillus lipopeptide, naamlik surfactin, fengycin en iturin, onder beheerde lottoestande ondersoek. Parameters wat lipopeptied produksie verhoog is gekwantifiseer, spesifiek antifungiese middels (iturin en fengycin) en lipopeptied produksie is geoptimeer. Eksperimente is uitgevoer in ‘n 1.3 L bioreaktor en lipopeptiedanaliese is met behulp van hoë druk vloeistof chromatografie en vloeistofchromatografie-massa spektroskopie uitgevoer. Van die vier moontlike Bacillus spp., was Bacillus amyloliquefaciens DSM 23117 die mees belowende antifungus-produserende kandidaat. Dit het beter resultate gelewer in terme van maksimale antifungiese produksie, Yp/x,antifungies (opbrengs per sel) asook antifungiese produktiwiteit. Nitraat, in hierdie geval NH4NO3, was noodsaaklik vir lipopeptied produksie en ‘n optimale konsentrasie is waargeneem waarbo die seldigtheid nie meer beduidend toegeneem het nie en beide die μmax (maksimale spesifieke groei tempo, h-1) en lipopeptied produksie afgeneem het. Die optimale NH4NO3 konsentrasie vir μmax was 10 g/L en vir lipopeptiedproduksie was 8 g/L. By 10 g/L NH4NO3 was μmax = 0.58 (h-1) en by 8 g/L was die maksimale antifungiese produksie (fengycin en iturin) 285.7 mAU*min en die maksimale surfactin produksie 302 mg/L onderskeidelik. Die lipopeptide, die antifungiese middels (fengycin en iturin) en surfactin, geproduseer deur B. amyloliquefaciens is sekondêre metaboliete, ongeag van die optimerings-behandelinge wat toegepas word, soos ‘n verhoging in NH4NO3 konsentrasie. Die gebruik van 30% verrykte suurstof het die nitraat verbruikingsperiode verleng, wat voorgestel het dat met die verryking, meer suurstof beskikbaar was om te dien as finale elektron ontvanger en sodoende die nitraat beskikbaar te stel vir lipopeptied produksie. Iturin en fengycin homoloë, oor die algemeen, het toegeneem soos wat die nitraat konsentrasie verhoog is. Hierdie resultate dui daarop dat prosestoestande, soos nitraat konsentrasie, gebruik kan word om die verhouding waarin lipopeptied homoloë geproduseer word te manipuleer. Hierdie resultate dui op die potensiaal vir die stroomop produksie van ‘n unieke bio-beheermiddel, wat die effektiwiteit van die bio-beheermetode moontlik sal verhoog. Die geproduseerde lipopeptiede het totale inhibisie getoon teen Botryotinia fuckeliana en ook fungiese aktiwiteit belemmer met Botrytis cinerea. Geen inhibisie is getoon teen Penicillium digitatum nie. Hierdie resultate toon die potensiaal van die bio-beheermetode, maar ‘n opskalerings-studie asook ‘n voerlot studie word aanbeveel, veral met die oog op moontlike kommersiële implementering van die strategie. Verdere studies met betrekking tot die aanwendingsmetode van die lipopeptiede moet ook verder ondersoek word, m.a.w. enkel teenoor menigte aanwendigs, aangesien dit die effektiwiteit van die lipopeptiede teen die teikenorganismes sal beïnvloed.

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