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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.
71

Biology and ecology of the introduced snail Microxeromagna armillata in south eastern Australia

Lush, Angela L. January 2007 (has links)
Thesis (Ph.D.)--University of Adelaide, School of Agriculture, Food and Wine, Discipline of Wine and Horticulture, 2007. / "January 2007" Bibliography: leaves 215-228. Also available in print form.
72

Yitronot la-godel ule-hitmaḥutṿe-opṭimizatsyah shel miḳum bate-arizah le-tapuzim ṿe/o le-eshkoliyot ...

Kedar, Mordechai. January 1972 (has links)
M.A. thesis. Hebrew University, Jerusalem. / Cover title: Economies of scale and of specialization and an improved "Stollsteimer" location model for orange and/or grapefruit packinghouses. At head of title: Miʹsrad ha-ḥaḳlaʼut ha-Sokh.ha-Y. Summary in English. Includes bibliographical references.
73

Fungicide resistance and genetic diversity of Penicillium digitatum in Hong Kong /

Lee, Suk-wah, January 2002 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 57-64).
74

Diversity of spiders in citrus ecosystems : implications for pest management /

Green, Janice Lynn. January 2005 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.
75

A model for evaluation alternative policy decision for the Florida orange subsector of the food industry

Powe, Charles E. January 1973 (has links)
Thesis (Ph. D.)--University of Florida, 1973. / Typescript. Vita. Includes bibliographical references (leaves 163-165).
76

Ecophysiological responses of citrus trees and sugar accumulation of fruit in response to altered plant water relations

Prinsloo, Johan Andries 03 1900 (has links)
Thesis (MSc (Horticulture))--University of Stellenbosch, 2007. / This study was undertaken to quantify some of the effects of daily fertigation on ecophysiological responses in citrus trees (Citrus spp.). Initial research was conducted to optimise and standardise the sampling procedure to quantify stem water potential (ψstem) in citrus trees. To reliably determine the plant water status of citrus trees, the following conditions are required to minimise unwanted variation in ψstem measurements. Bagging of leaves with black polyethylene envelopes covered with aluminium foil 3 to 4 hours prior to measuring ψstem allows the plant water status in those leaves to equilibrate with whole-tree plant water status, thereby providing a realistic measurement of the current water status. The use of aluminium foil to cover the bagged leaves, reduces unwanted heat stress by reflecting sunlight, and dramatically reduced variation in ψstem. The time of day at which ψstem measurements are made is important to ensure consistency in comparisons among treatments and interpretation of irrigation treatment effects. “Physiological midday” is the preferred time of day to measure ψstem, i.e. 1100 HR. Transpiring leaves with open stomata would be in sun-exposed positions on the east side of trees and should be used for making ψstem measurements. Under similar experimental conditions as those used here, only three leaves per replicate are required to detect a difference of 0.05 MPa in ψstem between treatment means. Plant water status categories were developed which may have useful practical applications, i.e. >-1.0 MPa = no water deficit; -1.0 to -1.2 MPa = low water deficit; -1.2 to -1.4 MPa = moderate water deficit; <-1.4 to -1.6 MPa = high water deficit; and <-1.6 MPa = severe water deficit. Attempts are being made to develop systems that improve crop management and enhance citrus fruit production through efficient and timeous application of water and mineral nutrients which has led to the use of daily drip fertigation or the open hydroponics system (OHS). However, the perceived benefits are not necessarily supported by facts. Fruit size and yield are apparently enhanced, but possible negative aspects of the system have not been quantified. Fruit produced on trees grown under daily drip fertigation generally have a lower total soluble solids concentration than on trees under micro-sprinkler irrigation. This is mainly due to a dilution effect that is caused by the greater availability of water and the uptake thereof. Sugar accumulation can be optimised by controlling the amount of water that the plant receives at different developmental stages. Therefore, it is essential to quantify the ecophysiological responses and benefits of OHS/daily fertigation, as well as the effects of this technology on fruit quality. ‘Nules Clementine’ mandarin (C. reticulata Blanco) trees in two commercial orchards in Simondium, Western Cape province, South Africa, received differential irrigation treatments. The treatments were applied at the end of stage I (± mid December) of fruit development. Stem water potential, fruit size and internal fruit quality were determined. Water-deficit stress enhanced sugar accumulation of ‘Nules Clementine’ mandarin by 0.3 to 0.6 °Brix under certain conditions. These conditions require that the difference in ψstem should be of a sufficient intensity of between 0.16 and 0.3 MPa, and this difference should be maintained for a sufficient duration of between 4 and 6 weeks. Furthermore, deficit irrigation should be applied relatively early in fruit development, namely during the sugar accumulation stage which starts within 4 weeks of the end of the fruit drop period and continues until harvest.
77

Factors affecting rind oil content of lemon (Citrus limon (L.) Burm. f.)

Van der Merwe, Hester E. (Hester Elizabeth) 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Essential oils are derived from volatile natural oils in plants and have been used by mankind for millennia. Citrus essential oils are widely used in various applications and lemon [Citrus limon (L.) Burm. f.] rind oil is the most important citrus oil in commerce. Rind oil glands are located in the exocarp, or flavedo, of the fruit and are formed schizogenously. The purpose of this study was to quantify the factors affecting rind oil content of lemons. The factors studied were light exposure and canopy position, growing region in South Africa, genotype, i.e. scion and rootstock, as well as the relationship between seedless clones of cultivars and the cultivars from which the seedless clones were derived, and various plant growth regulators were screened to determine whether they influenced rind oil content. Following the sampling of fruit from different positions in the tree's canopy, light exposure was found to affect rind oil content of 'Eureka' lemon fruit. Fruit borne on the outside of trees, higher in the tree, north-facing or not within the hedgerow had the highest rind oil content. Photosynthetically active radiation data supports the hypothesis that rind oil content is correlated with light exposure. To optimise rind oil content of lemons, trees should not be too dense or too high as to overshadow the lower parts of adjacent trees. South Africa has a diverse climate, and rind oil content from fruit produced in different growing regions was compared. 'Eureka' lemon fruit from Upington had the highest rind oil content in all seasons sampled. Fruit from Malelane and Marble Hall ranked second to Upington and rind oil content for fruit from Karino was intermediate. Rind oil content for fruit from Vaalharts was the lowest at each sampling time. When rind oil content was regressed against cumulative heat units there was a positive linear relationship in 2003, but in 2004 the relationship was weak. However, III general, rind oil content increased with increasing heat unit accumulation. A large variation exists among citrus cultivars and rootstocks and their effect on fruit growth and quality. 'Lirnoneira 8A', followed by 'Cicily', 'Lisbon' and 'Genoa' had the highest rind oil content. 'Villafranca', 'Messina' and 'Yen Ben Lisbon' had the lowest rind oil content. Rind oil content from 'Eureka' lemon fruit was disappointingly low. Seedless cultivars, 'Eureka SL' and 'Lisbon SL', had ~18.0% higher rind oil content than the seeded cultivars from which they were derived. With regards to rootstock, fruit from lemon trees budded on non-invigorating rootstocks, e.g. X639 [e. reshni Hort. ex Tan. x P. trifoliata (L.) Raf.], had the highest rind oil content, whereas rind oil content was low on invigorating rootstocks such as rough lemon (e. jambhiri Lush.). Synthetic gibberellins, cytokinins, ethylene and auxins were applied on lemon trees at different times and concentrations to screen their ability to enhance rind oil content. Of all the gibberellins and cytokinins applied, Promalin®, a combination of gibberellic acid 4/7 and benzyl adenine-phosphate, a cytokinin, had a small, but nonsignificant effect on rind oil content. Ethephon, which induces ethylene synthesis, affected rind oil content in 2004, when applied 8 weeks before harvest. However, ethephon and aminoethoxyvinylglycine (AVG, an ethylene biosynthesis inhibitor) had an inconsistent effect on lemon rind oil content. Auxins did not affect rind oil content. Further experiments should be conducted, especially on the timing and concentration of applied gibberellins, e.g. Promalin®, and ethephon. / AFRIKAANSE OPSOMMING: Essensiële olies is vlugtige, natuurlike plantolies wat al vir eeue deur die mens gebruik word. Sitrus essensiële olies het verskeie toepassings en van hierdie sitrus olies is dié verkry uit suurlemoenskil [Citrus limon (L.) Burm. f.] die belangrikste. Skiloliekliere is in die eksokarp, of flavedo, van die vrug geleë en vorm skisogenies. Die doelwit van hierdie navorsing was om faktore wat die olie-inhoud van suurlemoenskil affekteer te kwantifiseer. Faktore wat bestudeer is sluit ligblootstelling en posisie in die boom, produksiearea in Suid-Afrika, en genotipe (bo- en onderstam) in. Ook is saadlose klone vergelyk met die kultivars waaruit dit ontwikkel is. Verskeie plantgroeireguleerders se effek op skilolie-inhoud is ook geëvalueer. Ligblootstelling het skilolie-inhoud van 'Eureka' suurlemoene affekteer toe monsters van verskillende posisies in die boomtop vergelyk is. Vrugte aan die noorde- en buitekant, of hoër in die boom het die hoogste skilolie-inhoud gehad. Vrugte binne die plantry het minder skilolie bevat. Fotosinteties-aktiewe ligvlakmetings ondersteun die hipotese dat skilolieinhoud korreleer met ligblootstelling. Vir opitmale skilolie-inhoud in suurlemoene is dit dus belangrik dat bome nie te dig of te hoog moet wees nie, sodat dit nie die onderste dele van aangrensende bome oorskadu nie. Sitrus word in diverse klimaatstreke in Suid-Afrika verbou. Gevolglik is die skilolie-inhoud van vrugte uit verskillende produksieareas vergelyk. 'Eureka' suurlemoenvrugte uit Upington het met elke monsterneming die hoogste skilolie-inhoud gehad, gevolg deur vrugte uit Malelane en Marble Hall. Skilolie-inhoud van vrugte uit Karino was gemiddeld, terwyl vrugte van Vaalhaarts met elke monsterneming die laagste skilolie-inhoud gehad het. Regressie van skilolie-inhoud op kumulatiewe hitte-eenhede het 'n positiewe lineêre verwantskap in 2003 getoon. Hoewel die verwantskap swakker was in 2004, neem skilolieinhoud oor die algemeen toe met toenemende akkumulasie van hitte-eenhede. Sitruskultivars en -onderstamme varieer aansienlik in groeikrag en vrugkwaliteit. 'Lirnoneira 8A', gevolg deur 'Cicily', 'Lisbon' en 'Genoa' het die hoogste skilolie-inhoud gehad, terwyl 'Villafranca', 'Messina' en 'Yen Ben Lisbon' die laagste skilolie-inhoud gehad het. Die skilolie-inhoud van 'Eureka' suurlemoene was teleurstellend laag. Die skilolie-inhoud van die saadlose kultivars, 'Eureka SL' en 'Lisbon SL', was -18% hoër as die skilolie-inhoud van die kultivars waaruit dit ontwikkel is. Vrugte van bome wat op minder groeikragtige onderstamme geënt is, bv. X639 [C reshni Hort. ex Tan. x P. trifoliata (L.) Raf.], het 'n hoë skilolie-inhoud gehad, terwyl vrugte van bome op groeikragtige onderstamme, bv. growweskilsuurlemoen (C jambhiri Lush.), minder skilolie bevat het. Sintetiese gibberelliene, sitokiniene, etileen en ouksiene is op verskillende tye en teen verskillende dosisse op suurlemoenbome toegedien om die effek daarvan op skilolie-inhoud te bepaal. Promalin® (G~+7 en bensieladenienfosfaat) het 'n klein effek op skilolie-inhoud gehad, maar die effek was nie statisties beduidend nie. Ethephon, wat etileensintese induseer, het skilolie-inhoud in 2004 geaffekteer toe dit 8 weke voor oes toegedien is. Ethephon en aminoetoksievinielglisien (AVG, 'n etileenbiosintese inhibeerder) het egter nie 'n konstante effek op suurlemoen skilolie-inhoud gehad nie. Ouksiene het nie skilolie-inhoud geaffekteer me. Verdere eksperimente is veral nodig op die toedieningstyd en konsentrasie van toegediende gibberelliene, bv. Promalin®, en ethephon.
78

Determinação do estádio ótimo de maturação a colheita do limão ‘siciliano’, produzidos no Estado do Ceará / Determination of the great maturation stage to the harvest of the 'sicilian' lemon, produced in the State of Ceará

Almeida, Mariana Benigno de January 2014 (has links)
ALMEIDA, Mariana Benigno de. Determinação do estádio ótimo de maturação a colheita do limão ‘siciliano’, produzidos no Estado do Ceará. 2014. 73 f. Dissertação (Mestrado em Ciência e Tecnologia de Alimentos)-Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by Paulo Alencar (ppgcta@ufc.br) on 2017-09-28T17:00:11Z No. of bitstreams: 1 2014_dis_mbalmeida.pdf: 1697536 bytes, checksum: 7b7eaf63c9ac293350a2167e218c5a4c (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2017-10-03T15:46:21Z (GMT) No. of bitstreams: 1 2014_dis_mbalmeida.pdf: 1697536 bytes, checksum: 7b7eaf63c9ac293350a2167e218c5a4c (MD5) / Made available in DSpace on 2017-10-03T15:46:21Z (GMT). No. of bitstreams: 1 2014_dis_mbalmeida.pdf: 1697536 bytes, checksum: 7b7eaf63c9ac293350a2167e218c5a4c (MD5) Previous issue date: 2014 / The state of Ceará is gaining attention as an emerging state in fruit production in the country. Lemons 'Sicilians', traditionally grown in the south, has been planted in this region, however, there still exist a lot of information about the quality of fruits grown locally. Lemon ‘Siciliano’ hybrid 'Eureka' is a non-climacteric fruit, should be harvested, bought and traded with their quality attributes related to the ideal flavor for consumption. The study aimed to determine the proper stage of maturity lemon ‘Siciliano’ at harvest through physical and physicochemical periodic measurements during development and fruit growth. Two experiments were conducted, following two separate flowerings. The first four samples were taken every 15 days and from the 49th day, the crops became every 7 days until the 91 th day being thus held a total of 11 samples at 0, 14, 28, 42 , 49, 56, 63, 70, 77, 84 and 91 days. . At each time, a total of 20 fruits were divided into 4 groups were collected and, thus, five replicates. The first experiment was conducted from October 2012 to January 2013 and the second in the months from July to October 2013. Fruits were assessed for physical and physicochemical characteristics: fresh weight, longitudinal and transverse diameters (DL / DT), format index, firmness of the peel, juice yield, thickness of the peel, color (h*, C* and L*) and chlorophyll content of the peel, pH, titratable acidity (TA), soluble solids (SS), SS/TA relationship and ascorbic acid content. An increase (p ≤ 0.05) of the variables: fresh weight, DL, DT and juice yield, in both experiments, was observed, while the color parameters of pH, L* and C* increased only in the first and SS in the second. Already, the variables chlorophyll and firmness of the peel decreased significantly, in both experiments, whereas the color parameter h* and ascorbic acid content decreased only in the first experiment and thickness of the peel, only the second. Thus, the end of the study of the development of lemons, it is concluded that the fruits were able to be picked at its optimum stage to harvest maturity after 77º days. / O estado do Ceará vem ganhando atenção como um Estado emergente na produção de frutos no país. Limões ‘Sicilianos’, tradicionalmente cultivados no sul, vem sendo plantados nesta região, no entanto, ainda não existem muitas informações sobre a qualidade destes frutos cultivados localmente. O limão ‘Siciliano’ híbrido ‘Eureka’ é um fruto não-climatérico, devendo ser colhido, comprado e comercializado com seus atributos de qualidade relacionados ao sabor ideal para o consumo. O trabalho objetivou a determinação do estádio de maturação apropriado do limão ‘Siciliano’ por ocasião da colheita através de medições periódicas físicas e físico-químicas durante o desenvolvimento e crescimento do fruto. Foram realizados dois experimentos, acompanhando duas floradas distintas. As quatro primeiras colheitas foram realizadas a cada 15 dias e a partir do 49° dia, as colheitas passaram a ser a cada 7 dias até o 91° dia sendo, assim, realizado um total de 11 colheitas nos tempos 0, 14, 28, 42, 49, 56, 63, 70, 77, 84 e 91 dias para cada experimento. Em cada tempo, foram colhidos um total de 20 frutos que foram divididos em grupos de 4, constituindo assim, cinco repetições. O primeiro experimento foi realizado nos meses de outubro de 2012 a janeiro de 2013 e o segundo nos meses de julho a outubro de 2013. Os frutos foram avaliados quanto às características físicas e físico-químicas: massa fresca, diâmetros longitudinais e transversais (DL/DT), índice de formato, firmeza da casca, rendimento de suco, espessura da casca, cor (h*, C* e L*), conteúdo de clorofila da casca, pH, acidez titulável (AT), sólidos solúveis (SS), relação SS/AT e teor de ácido ascórbico. Foi observado um aumento (p≤0,05) das variáveis: massa, DL, DT e rendimento de suco, nos dois experimentos, enquanto os parâmetros de pH, cor C* e L* aumentaram apenas no primeiro e SS, no segundo. Já, as variáveis firmeza e clorofila da casca reduziram significativamente nos dois experimentos, ao passo que o parâmetro de cor h* e o teor de ácido ascórbico reduziram apenas no primeiro experimento e a espessura da casca, apenas no segundo. Dessa forma, ao final do estudo do desenvolvimento dos limões sicilianos, conclui-se que, os frutos estavam aptos a serem colhidos em seu estádio ótimo de maturação à colheita no 77º dia.
79

Processos biocatalíticos utilizando a casca da laranja da terra (Citrus aurantium L.) / Biocatalytic processes using the orange peel of the earth (Citrus aurantium L.)

Rodrigues, Francisco Eduardo Arruda January 2012 (has links)
RODIGUES, F. E. A.; LEMOS, T. L. G. Processos biocatalíticos utilizando a casca da laranja da terra (Citrus aurantium L.). 2012. 141 f. Dissertação (Mestrado em Química) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2012. / Submitted by José Jairo Viana de Sousa (jairo@ufc.br) on 2014-11-06T21:11:40Z No. of bitstreams: 1 2012_dis_ffmsilva.pdf: 4587488 bytes, checksum: 958fd1d877db405b9fab0c8299731f6a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa(jairo@ufc.br) on 2015-11-24T17:47:47Z (GMT) No. of bitstreams: 1 2012_dis_ffmsilva.pdf: 4587488 bytes, checksum: 958fd1d877db405b9fab0c8299731f6a (MD5) / Made available in DSpace on 2015-11-24T17:47:47Z (GMT). No. of bitstreams: 1 2012_dis_ffmsilva.pdf: 4587488 bytes, checksum: 958fd1d877db405b9fab0c8299731f6a (MD5) Previous issue date: 2012 / The Brazil is the producing greater of world of orange and orange juice, being this sector of great importance for Brazilian, responsible economy for generating 400 thousand jobs and more than and putting into motion ciphers of billions per year. But, this sector also is responsible for the production of great amount of industrial rejetcs, that are equivalent 50% of the weight of the fruit, being these used residues most of the time as animal ration. Therefore the use efficient of these rejetcs if makes necessary in a world where the natural reserves come if depleting. In this direction biocatalysis is presented as a promising tool in the use of these residues, that contains enzymes in its constitution, for attainment of products of high added value, the substances enantiopure. The application of different methodologies, practical and of low cost, made possible the chiral alcohols synthesis with high enantiomeric excess (ee) and good taxes of conversion. Hydrolysis reactions and reduction had been processed in aqueous way e, the reactions of esterification had been carried through in organic solvent, using the rind of the orange as source of biocatalysis for such reactions. The use of the peel of the orange as biocatalysis source presented resulted sufficiently promising, demonstrating catalytic capacity in some reactions (reduction/oxidation, hydrolysis/esterification) through simple methodologies and of low cost. Conversions of 46,90-96,70% had been reached in the reactions of bioreduction shown of ee varying of 21,15-99,00%. In the hydrolysis reactions taxes of 19,20-80,82% conversions and ee had been verified varying of 9,60-45,52%. Already in the esterification reactions, ee above of 99% had been observed and bigger conversions that 80% had been reached. From there, this study it opens precedents for an ample band of application of this source of biocatalysis (pells of the orange), that currently it is considered as one reject industrial, contributing excessively to add value all a productive and industrial sector in which Brazil is leader, the orange juice industry / O Brasil é o maior produtor mundial de laranja e de suco de laranja, sendo este setor de grande importância para economia brasileira, responsável por gerar mais de 400 mil empregos e movimentar cifras de bilhões de reais por ano. Mas, este setor também é responsável pela produção de grande quantidade de rejeitos industriais, que equivalem a 50% do peso da fruta, sendo estes resíduos utilizados na maioria das vezes como ração animal. Portanto o uso eficiente destes rejeitos se faz necessário em um mundo em que as reservas naturais vêm se esgotando. Neste sentido a biocatálise mostra-se como uma ferramenta promissora no uso destes resíduos, que possuem enzimas em sua constituição, para obtenção de produtos de alto valor agregado, as substâncias enantiopuras. A aplicação de diferentes metodologias, práticas e de baixo custo, possibilitou a síntese de alcoóis quirais com alto excesso enantiomérico (ee) e boas taxas de conversão. Reações de hidrólise e redução foram processadas em meio aquoso e, as reações de esterificação foram realizadas em solvente orgânico, utilizando as casca da laranja como fonte de biocatalisadores. O uso das cascas da laranja como fonte de biocatalisador apresentou resultados bastante promissores, demonstrando capacidade catalítica em várias reações (redução/oxidação, hidrólise/esterificação) através de metodologias simples e de baixo custo. Conversões de 46,90-96,70% foram alcançadas nas reações de biorredução acompanhado de ee variando de 21,15-99,00%. Nas reações de hidrólise verificaram-se taxas de conversões de 19,20-80,82% e ee variando de 9,60-45,52%. Já nas reações de esterificação, ee acima de 99% foram observados e conversões maiores que 80% foram alcançadas. Portanto, este estudo abre precedentes para uma ampla faixa de aplicação desta fonte de biocatalisador (cascas da laranja), que atualmente é considerado como um rejeito industrial, contribuindo sobremaneira para agregar valor a todo um setor produtivo e industrial no qual o Brasil é líder, a indústria de suco de laranja.
80

Interactive effects of cucurbitacin-containing phytonematicides and biomuti on growth of citrus rootstock seedlings and accumulation of nutrient elements in leaf tissues

Mokoele, Tlou January 2019 (has links)
Thesis (M.Sc. Agriculture (Horticulture)) -- University of Limpopo, 2019 / Cucurbitacin-containing phytonematicides and a variety of unidentified soil microbes in suppressive soils (Biomuti) had been consistent in suppression of population densities of root-knot (Meloidogyne spp.) nematodes on various crops. However, information on suppressive effects of cucurbitacin-containing phytonematicides and Biomuti on citrus growth and suppression of the citrus nematode (Tylenchulus semipenetrans) had not been documented. The objective of this study therefore, was to determine the interactive effects of Nemarioc-AL and Nemafric-BL phytonematicides and Biomuti on growth and nutrient elements in leaf tissues of Poncirus trifoliata rootstock seedlings under greenhouse and field conditions. Uniform six-month-old citrus rootstock seedlings [Du Roi Nursery (Portion 21, Junction Farm, Letsitele)] were transplanted in 4 L plastic bags filled with growing mixture comprising steam-pasteurised (300°C for 1 h) loam and compost (cattle manure, chicken manure, sawdust, grass, woodchips and effective microorganisms) at 4:1 (v/v) ratio and placed on greenhouse benches. A 2 × 2 × 2 factorial experiment with the first, second and third factors being Nemarioc-AL phytonematicide (A) and Nemafric-BL phytonematicide (B) and Biomuti (M), were arranged in randomized complete block design, with 10 blocks. The treatment combinations were A0B0M0, A1B0M0, A0B1M0, A0B0M1, A1B1M0, A1B0M1, A0B1M1 and A1B1M1, with 1 and 0 signifying with and without the indicated factor. Treatments were applied at 3% dilution for each product as substitute to irrigation at a 17-day application interval. Under greenhouse conditions, seedlings were irrigated every other day with 300 ml chlorine-free tap water. Under field conditions, the study was executed using similar procedures to those in the greenhouse trial, except that the citrus seedlings were transplanted directly into the soil of a prepared field and seedlings were irrigated using drip irrigation for 2 h every xxi other day. At 64 days after transplanting, plant growth variables were measured and foliar nutrient elements were quantified using the Inductively Coupled Plasma Optical Emission Spectrometry (ICPE-9000). Data were subjected to analysis of variance using SAS software. Significant second and first order interactions were further expressed using the three-way and two-way tables, respectively. At 64 days after the treatments, under greenhouse conditions Nemarioc-AL × Nemafric-BL × Biomuti interaction was not significant (P ≤ 0.05) on plant variables of seedling rootstocks in both experiments. In contrast, the Nemarioc-AL × Biomuti interaction was highly significant (P ≤ 0.01) on stem diameter, contributing 52% in TTV of the variable in Experiment 1 (Table 3.1), whereas in Experiment 2 the interaction was highly significant on dry shoot mass, contributing 33% in TTV of the variable (Table 3.2). Relative to untreated control, the two-way matrix showed that the Nemarioc-AL × Biomuti interaction, Nemarioc-AL phytonematicide and Biomuti each increased stem diameter by 1%, 12% and 5%, respectively (Table 3.3). Relative to untreated control, the two-way matrix table showed that Nemarioc-AL × Biomuti interaction increased dry shoot mass by 10%, whereas Nemarioc-AL phytonematicide and Biomuti each increased dry shoot mass by 23% and 17%, respectively (Table 3.4). Nemarioc-AL × Nemafric-BL × Biomuti interaction was not significant (P ≤ 0.05) for all plant growth variables in both experiments. However, Nemarioc-AL × Nemafric-BL interaction was significant for leaf number and stem diameter contributing 45% and 29% in TTV of the respective variables in Experiment 2 (Table 4.1). Relative to untreated control, two way matrix table showed that the Nemarioc-AL × Nemafric-BL interaction and Nemafric-BL phytonematicides each increased stem diameter by 8% and 11% respectively, whereas Nemarioc-AL phytonematicides reduced stem diameter by 2% (Table 4.2). Also using two-way matrix table showed that Nemarioc-AL and Nemafric xxii BL phytonematicides each increased leaf number by 1% and 7% respectively, whereas the Nemarioc-AL × Nemafric-BL interaction increased leaf number by 6% (Table 4.2). Nemafric-BL × Biomuti interaction was significant for stem diameter contributing 29% in TTV of the respective variable in Experiment 2 (Table 4.1). Using two-way matrix table showed that Nemafric-BL × Biomuti interaction and Nemafric-BL phytonematicide each increased stem diameter by 7%, whereas Biomuti alone reduced stem diameter by 6% (Table 4.3). Under greenhouse conditions, the second order Nemarioc-AL × Nemafric-BL × Biomuti interaction was highly significant for foliar Mg, contributing 5% in TTV of the variable in Experiment 1 (Table 3.4). Relative to untreated control, the three-way matrix table showed that the three factors, Nemafric BL phytonematicide and Biomuti each reduced Mg by 33%, 35% and 53%, respectively, whereas Nemarioc-AL phytonematicide increased Mg by 12% (Table 3.5). Nemarioc-AL × Biomuti interaction was highly significant for foliar Mg, contributing 9% in TTV of the variable in Experiment 1 (Table 3.4). Relative to untreated control, the two-way matrix table showed that the Nemarioc-AL × Biomuti interaction and Nemafric-BL phytonematicide reduced Mg by 42% and 12%, respectively, whereas Nemarioc-AL phytonematicide alone increased Mg by 14% (Table 3.6). Nemarioc-AL × Biomuti interaction was highly significant for foliar Ca and Mg, contributing 59 and 4% in TTV of the respective variables in Experiment 1 (Table 3.4). Also using two-way matrix table showed that Nemarioc-AL phytonematicide and Biomuti separately reduced Ca by 12% and 22% respectively, whereas the Nemarioc-AL × Biomuti interaction increased Ca by 1% (Table 3.7). Relative to untreated control, the Nemarioc-AL × Biomuti interaction, Nemarioc-AL phytonematicide and Biomuti reduced foliar Mg by 26%, 21% and 33%, respectively (Table 3.7). Nemafric-BL × Biomuti interaction was highly significant for foliar Mg and P, contributing 50 and 21% xxiii in Experiment 1, whereas in Experiment 2 the interaction was significant for foliar Ca and Mg, contributing 41% and 38% in TTV of the respective variables (Table 3.4). Relative to untreated control, the two-way matrix table showed that Nemafric-BL phytonematicide and Biomuti individually reduced Mg by 60% and 51%, respectively, whereas the Nemafric-BL × Biomuti interaction reduced Mg by 38% (Table 3.8). Also, in the two-way matrix table the Nemafric-BL × Biomuti interaction and Nemafric-BL phytonematicide each reduced Mg by 13% and 2%, respectively, whereas Biomuti alone increased P by 17% (Table 3.8). Relative to untreated control, Nemafric-BL phytonematicide and Biomuti reduced Ca by 29% and 18%, respectively, whereas Nemafric-BL × Biomuti interaction reduced Ca by 14% (Table 3.9). Using two-way matrix table showed that Nemafric-BL phytonematicide and Biomuti separately reduced Mg by 21%, whereas the Nemafric-BL × Biomuti interaction reduced Mg by 16% (Table 3.9). Interaction of Nemarioc-AL × Nemafric-BL × Biomuti had no significant effect on K, Na and Zn in both experiments. Under field conditions, the second order Nemarioc-AL × Nemafric-BL × Biomuti interaction was not significant for all the nutrient elements in Experiment 1. Nemarioc-AL × Biomuti was significant for Ca, K and highly significant for Mg and P, contributing 31, 8, 23 and 19% in TTV of the respective variables in Experiment 1 (Table 4.4). Relative to untreated control, two-way matrix table showed that Nemarioc-AL phytonematicide and Biomuti each increased Ca by 15% and 26% repectiviely, whereas the Nemarioc-AL × Biomuti increased Ca by 17% (Table 4.5). Interaction of Nemarioc-AL × Biomuti, Nemarioc-AL phytonematicide and Biomuti each reduced Mg by 48%, 70% and 37% (Table 4.5). Also using two-way matrix table showed that Nemarioc-AL phytonematicide and Biomuti each increased P by 4% and 5% respectively, whereas the Nemarioc-AL × Biomuti interaction increased P by 50% (Table 4.5). Realative to untreated control, xxiv Biomuti and Nemarioc-AL phytonematicide each reduced K by 10% and 5% respectively, whereas the Nemarioc-AL × Nemafric-BL interaction reduced K by 38% (Table 4.7). Nemafric-BL × Biomuti interaction was highly significant for Mg and Zn, contributing 11% and 29% in TTV of the respective variables in Experiment 1 (Table 4.4). Relative to untreated control, two-way matrix table showed that Nemarioc-AL phytonematicide and Biomuti separately increased Mg by 1% and 19% respectiviely, whereas the Nemafric-BL × Biomuti interaction reduced Mg by 43% (Table 4.6). Nemafric-BL × Biomuti interaction, Nemafric-BL phytonematicide and Biomuti each reduced Zn by 35%, 31% and 64% (Table 4.6). Using three-way matrix table showed that the Nemarioc-AL × Nemafric-BL × Biomuti, Nemarioc-AL × Nemafric-BL, Nemarioc-AL × Biomuti and Nemafric-BL × Biomuti interactions each increased Ca by 44%, 18%,10% and 24% (Table 4.8). Further the matrix showed that Nemarioc-AL, Nemafric-BL phytonematicides and Biomuti each increased Ca by 25%, 31% and 23% (Table 4.8). Under both greenhouse and field conditions, although second and first order interactions were not consistent of various variables, results demonstrated that the three products interacted significantly for various products. In conclusion, the study suggested that these innovative products could be used in combination with Biomuti to stimulate plant growth but had antagonistic effects on accumulation of nutrient elements in P. trifoliata rootstock seedlings, suggesting that the products should be applied separately. / Agricultural Research Council-Universities Collaboration Centre and the National Research Foundation (NRF)

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