Spelling suggestions: "subject:"linda"" "subject:"linde""
1 |
Die moontlike rol van Oumansoutbos (Atriplex Nummularia Lindl.) as weigewas in hoë reënvalgebiede (Afrikaans)Verschoor, Aart-Jan 03 May 2010 (has links)
OMSB het gunstig op bemesting in die saailingfase, waar die groeimedium ‘n swak voedingstatus gehad het gereageer. ‘n Swak reaksie op bemesting na verplanting is verkry, waarskynlik omdat die voedingstatus van die grand waarin plante gevestig is, gunstig was. Die invloed van suurheidsgraad op OMSB, veral op saailinge, word moontlik oorskat. Aangesien die reaksie van OMSB op kaliumlnatriumsout-bemesting beperk was, is dit moontlik dat die gewas soute in plantweefsel stoor, en dus ‘n luukse voeder van elemente soos kalium en natrium is. Terrasorb verbeter die waterhouvermoë van gronde beduidend. Op swaar grande kan hierdie verhoging in waterhouvermoë egter ‘n negatiewe invloed op die groeikragtigheid van plante hê. Die effektiwiteit van Terrasorb hang grootliks van die voghuishouding af. Indien vog beperkend is, kan Terrasorb die groei van OMSB in beide ligte en swaarder gronde bevorder, terwyl dit die groei van OMSB in kleigrond kan inhibeer indien vog vrylik beskikbaar is. Gedurende die tydperk Oktober 1990 tot Februarie 1991, het OMSB plante in Pretoria gemiddeld 20g nat materiaal/dag en 6.8g droë materiaal (DM) per dag geproduseer. Dit is ongeveer nege ton nat materiaal/ha en drie ton DM/ha, oor ‘n periode van 150 dae. Die produksiepotensiaal en groeitempo van OMSB vergelyk besonder gunstig met die van ander weidingsgewasse. Die graad van terugsnoei voor verplanting, het binne redelike perke, nie ‘n beduidende negatiewe effek op saailingontwikkeling gehad nie. Vog was egter vrylik beskikbaar en onder meer stremmende toestande kan groei waarskynlik gestrem word. Die graad van ontblaring na verplanting het 'n beduidende invloed op die herstelvermoë van OMSB gehad. Verskille in groeitempo is tussen plante wat tot op verskillende hoogtes gesnoei is, gemeet. Die gemiddelde groeitempo van plante onderworpe aan die somer snoeibehandeling, was effens laer as dié van plante onderworpe aan 'n lente behandeling. Hierdie plante het egter 'n korter aktiewe groeiperiode as plante wat in die lente gesnoei is, gehad. 121 GVE (Grootvee eenheid) weidae/ha en 253 GVE weidae/ha is met onderskeidelik die matige en swaar benuttings verkry, wat aandui dat 'n relatief hoë weidingskapasiteit dus met OMSB verkry kan word. Die herstelvermoë van OMSB, soos gemeet in terme van DM opbrengs en met behulp van oppervlakte projeksies, was selfs na 'n totale benutting, relatief goed. Plante wat totaal benut was, was egter tot 'n baie groter mate aan afsterwing onderworpe. Hierdie tendense is met die herfs-, winter- en lente benutting gevind. OMSB is waarskynlik beter aangepas by matige benutting. Plante wat straf ontblaar word, is waarskynlik meer gevoelig vir stremming. OMSB kan meer as een maal per jaar effektief benut word, mits ontblaring nie oormatig is nie. Die weidingskapasiteit van die gewas kan moontlik met effektiewe bestuur aansienlik verhoog word. Diereprestasie mag ook, wanneer 'n matige weidruk toegepas word, as gevolg van die seleksie van 'n hoër kwaliteit dieet toeneem. ENGLISH: The aim of this study was to determine the value of Oldman Saltbush (OMS) as an alternative fodder in areas with a relatively high rainfall. Aspects that were studied were establishment. reaction to fertilization. production and reaction to utilization. OMS reacted positively to fertiliser in the seedling phase. where the growing medium had a poor nutrient status. a Poor reaction to fertilisation was obtained after transplanting. probably because of the favourable nutrient status of the particular soil. The influence of soil acidity. on OMS. particularly on seedlings. is probably overrated. As OMS showed a limited reaction to sodium/potassium fertilisation. it is argued that OMS stores salts in plant tissue and probably is a luxury feeder of elements such as potassium and sodium. Terrasorb improves the water holding capacity of soil significantly. On heavier soil this increase in water holding capacity could have a negative effect. The effectivity of Terrasorb depends greatly on the current moisture situation. Terrasorb could enhance growth in both light and heavy soil if moisture is a limiting factor. Where moisture is not limiting. growth in heavy soil could be inhibited. During the period October 1990 until February 1991. OMS plants in Pretoria produced 20g wet material and 6.8g dry material (OM) per day on average. This amounts to approximately nine tons of wet material/ha and three tons of DM/ha. in 150 days. The production of OMS compares favourably with that of other fodder crops. The degree of defoliation before transplanting did not. within limits. had a significant negative influence on seedling development. Moisture. however. was not a limiting factor and growth probably could be inhibited under stress. The degree of defoliation after transplanting, had a significant effect on the recovery of OMS. Differences in growth rate were found between plants defoliated to different heights. The mean growth rate of plants defoliated during summer, was somewhat lower as the growth rate found for plants defoliated during spring, probably because the recovery period was shorter. A total of 121 Large stock unit (LSU) grazing days/ha and 253 LSU grazing days/ha were obtained with the moderate and severe utilizations respectively, which shows that a relatively high grazing capacity can be obtained with OMS. The recovery potential of OMS as measured in terms of DM yield and with area projections was, even after severe utilization, relatively good. The survival rate of OMS was, however, significantly higher when plants were moderately utilized. This was found with autumn-, winter- and spring utilization. OMS is probably better adapted to moderate utilization. Plants that are severely utilized, are probably more susceptible to stress. OMS can be utilized effectively more than once a year, if defoliation is moderate. The grazing capacity of this crop could possibly be increased with effective management, while animal production might increase with the selection of a higher quality diet, when moderate grazing pressures are applied. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted
|
2 |
Pós-colheita de frutos de ameixa armazenados em temperatura ambiente e a 1ºC tratados e armezenados em temperatura ambiente e a 1º C tratados com EtefomBauchrowitz, Iohann Metzger 01 August 2018 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-10-19T12:57:01Z
No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Iohann Metzger .pdf: 2446573 bytes, checksum: b496303d3bde21c766b8b82d72b53870 (MD5) / Made available in DSpace on 2018-10-19T12:57:01Z (GMT). No. of bitstreams: 2
license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5)
Iohann Metzger .pdf: 2446573 bytes, checksum: b496303d3bde21c766b8b82d72b53870 (MD5)
Previous issue date: 2018-08-01 / A cultura da ameixeira apresenta um enorme potencial de crescimento no Brasil, as pesquisas no brasil para o desenvolvimento de novas variedades, tiram como base os materiais de origem asiáticos, implantados nos estados, do sul do pais, sendo realizados diversos cruzamentosvisando a obtenção de variedades adaptadas ao clima, resistentes a doenças e com maiores períodos de armazenamento de seus frutos, período de armazenamento é menor do que outras frutíferas principalmente porque a ameixa é uma fruta climatérica e apresenta continuidade nos seus processos de maturação, respiração e transposição após ser colhida. Desta forma são necessárias estratégias de colheita e armazenamento para aumentar a vida útil dos frutos e de transporte, fatores que causam elevação nos preços dos frutos para o consumidor. Este trabalho teve como objetivo conhecer o desenvolvimento climatérico dos frutos, a capacidade de armazenamento e de qualidade dos frutos de ameixeira japonesa (Prunus salicina Lind), genótipos de ameixa japonesa desenvolvidos no programa de melhoramento genético do Instituto Agronômico do Paraná. Foram realizados dois experimentos. O primeiro foi realizado comquatro genótipos, armazenados em temperatura ambiente e temperatura refrigerada a 1°C e analisada suas qualidades em oito épocas de armazenamento. Para o segundo experimento foram utilizadosdois genótipos de ameixa, armazenados em temperatura ambiente erefrigerado 1°C, e tratados ou não com Etefom, e nove épocas de avaliação. As análises realizadas nos frutos em cada uma das épocas foram, diâmetro, massa e firmeza dos frutos, perda de massa fresca, coloração L,A,B e transformação do ângulo Hue, sólidos solúveis, acidez titulável, ratio e pH. A capacidade de armazenamento dos frutos em condições de temperatura ambiente é menor do que se comparados com os frutos quando armazenados em temperatura refrigerada nos dois experimentos.Os frutos de todos os genótipos no momento da colheita apresentaram diâmetro superior a 44,00mm, e massa dos frutos superior a 50gramas sendo estes resultados de maior expressão na qualidades fisicas dos frutos, em relação as qualidades quimicas dos frutos é possivel observar que no momento da colheita foram obtidos resultados de SS superiores a 9° Brix, e com o avanço da maturação os valores de SS chegaram proximos de 15°Brix, enquanto que a AT no momento da colheita apresentava valores de 1,00% e após o armazenamento os valores obtidos foram inferiores a 0,5%.Conclui-se com este trabalho que todos os genótipos estudados apresentam comportamento climatérico, com diferentes periodos de armazenamentos e capacidades distintas seja quando estes frutos, são armazenados em temperatura ambiente ou em temperatura refrigerada 1°C, ocorreu em todos os genótipos variçoes entre os momentos de colheita e final do armazenamento, sendo os resultados de maior expressão obtidos na perda de massa fresca dos frutos armazenados em temperatura refrigerada 1°C com aplicação de Etefom, e elevação do ratio e SS, nos frutos em ambos os locais de armazenamento. / The plum cultivation has enormous potential for growth in Brazil, research in Brazil for the development of new varieties, based on the Asian origin materials, implanted in the states, in the south of the country, with several crosses being carried out in order to obtain resistant to diseases and with longer periods of storage of their fruits, storage period is lower than other fruits, mainly because the plum is a climacteric fruit and presents continuity in its maturation, respiration and transposition processes after being harvested . In this way, harvest and storage strategies are required to increase fruit shelf life and transport, factors that cause a rise in fruit prices for the consumer. The objective of this work was to know the climacteric development of fruits, storage capacity and quality of Japanese plum fruits (Prunus salicina Lind), Japanese plum genotypes developed in the breeding program of the Agronomic Institute of Paraná. Two experiments were carried out. The first one was carried out with four genotypes, stored at room temperature and refrigerated temperature at 1 ° C and analyzed for their qualities in eight storage periods. For the second experiment, two plum genotypes were used, stored at room temperature and refrigerated at 1 ° C, and treated or not with Etefom, and nine evaluation periods. Fresh fruit weight loss, L, A, B color and Hue angle transformation, soluble solids, titratable acidity, ratio and pH were analyzed in the fruits at each time point. The storage capacity of fruits at ambient temperature conditions is lower than when compared to fruits when stored at refrigerated temperature in the two experiments. Fruits of all genotypes at harvest had a diameter greater than 44.00 mm, and mass of fruits greater than 50grams being these results of greater expression in the physical qualities of the fruits, in relation to the chemical qualities of the fruits it is possible to observe that at the moment of the harvest SS results were obtained higher than 9 ° Brix, and with the advancement of the maturity values of SS reached close to 15 ° Brix, while TA at the time of harvest had values of 1.00% and after storage the values obtained were less than 0.5%. It is concluded with this work that all the genotypes studied climatic behavior, with different storage periods and different capacities, when stored in or in refrigerated temperature 1 ° C, all the genotypes occurred between the harvesting and the final moments of the storage, with the highest expression results obtained in the loss of fresh mass of the fruits stored in refrigerated temperature 1 ° C with application of Etefom , and elevation of the ratio and SS in fruits at both storage sites.
|
3 |
Membrane studies in Japanese plums (Prunus salicina Lindl.)Jooste, Mariana 12 1900 (has links)
ENGLISH ABSTRACT: The export of Japanese plums from South Africa is challenging, since most cultivars are prone to
develop chilling injury (CI) when stored at low temperatures. This injury manifests as gel
breakdown or internal browning in the mesocarp tissue of the fruit on removal from low storage
temperature conditions, i.e. in the consumer’s fruit basket, who subsequently does not buy plums
again.
Loss of cell membrane integrity and oxidative stress are, respectively, the primary and secondary
physiological responses to CI. The main aim of this study was to investigate changes in cell
membrane composition and levels of antioxidants in plums throughout fruit development and
maturation, during forced air cooling (FAC) and storage under different temperature regimes.
‘Sapphire’ (a chilling susceptible cultivar) accumulated high levels of glutathione and
polyunsaturated fatty acids (PUFAs) during fruit development. Therefore, the cultivar is protected
against lipid peroxidation while developing on the tree, but the high levels of PUFAs, which are
easily oxidised, may cause this cultivar to be chilling susceptible when stored at low temperatures.
It is suggested that the high levels of monounsaturated fatty acids (MUFAs), which are not easily
oxidised, and ascorbic acid that accumulated in ‘Angeleno’ (a chilling resistant cultivar) during fruit
development, render this cultivar CI resistant during long-term cold-storage.
When stored at -0.5 °C, CI development increased at a higher rate, ethylene evolution rates were
higher and water soluble antioxidant activity (HAA), ascorbic acid and glutathione levels, and the
MUFA:PUFA ratio were lower in H2 (more mature) ‘Sapphire’ plums than H1 fruit (less mature).
Therefore, concurrent with H2 fruit having lower levels of antioxidants to quench free radicals
caused by chilling stress, their cell membranes were more vulnerable to oxidation due to their
phospholipid fatty acid composition. H2 fruit also had higher levels of saturated fatty acids, and
hence less fluid cell membranes than H1 fruit when stored at -0.5 °C.
An intermittent warming (IW) regime delayed symptom appearance and reduced CI severity in
plums significantly compared to storage at -0.5 °C. Fruit stored under the IW regime had a more optimal phospholipid fatty acid composition and lower membrane sterol levels under shelf-life
conditions to keep the membranes fluid. It also had higher levels of HAA and lipid soluble
antioxidant activity, ascorbic acid and glutathione, which rendered fruit better protected against
oxidation.
Elevated storage temperatures (2.5 °C to 7.5 °C) caused higher levels of lipid peroxidation or low
ascorbic acid levels and poor fruit quality compared to the IW regime in ‘Sapphire’ plums. ‘Laetitia’
plums stored at 5 °C and 7.5 °C had significantly less CI than under the IW regime, but softened
quicker due to higher ethylene evolution rates.
‘Sapphire’ tolerated both long and short FAC durations, but a slower initial FAC rate prevented CI
manifestation and caused a higher HAA after cold-storage in this fruit. ‘Laetitia’ cooled with a
slower initial FAC rate and for a longer duration resulted in the best fruit quality and had higher
HAA, total phenolic, phospholipid and saturated phospholipid fatty acid concentrations during
storage. / AFRIKAANSE OPSOMMING: Die uitvoer van Japanese pruime vanaf Suid-Afrika hou talle uitdagings in, want die meeste van die
kultivars ontwikkel koueskade wanneer hulle by lae temperature opgeberg word. Koueskade
manifesteer as gelverval of interne verbruining in die mesokarpweefsel van die vrugte wanneer die
vrugte verwyder word uit die lae opbergingstemperatuuromstandighede, m.a.w. in die verbruiker se
vrugtemandjie, wat nie weer pruime koop nie.
Verlies aan selmembraanintegriteit en oksidatiewe druk is, respektiewelik, die primêre and
sekondêre fisiologiese reaksies op koueskade. Die hoofdoel van hierdie studie was om die
veranderinge in selmembraansamestelling en antioksidantkonsentrasie in pruime te ondersoek
tydens vrugontwikkeling en volwassewording, tydens geforseerde lugverkoeling (GLV) en tydens
opberging onder verskillende temperatuurregimes.
‘Sapphire’ (‘n koueskade sensitiewe kultivar) het hoër konsentrasies van glutatioon en polionversadigde
vetsure (POV) tydens vrugontwikkeling geakkumuleer. Dié kultivar is dus voldoende
beskerm teen lipiedperoksidasie tydens vrugontwikkeling aan die boom, maar die hoë
konsentrasies van POVs, wat maklik oksideer, mag veroorsaak dat hierdie kultivar meer
koueskadesensitief is wanneer dit by lae temperature opgeberg word. Die hoë konsentrasies van
mono-onversadigde vetsure (MOV), wat nie maklik oksideer nie, en askorbiensuur wat in
‘Angeleno’ (‘n koueskade weerstandbiedende kultivar) geakkumuleer het tydens vrugontwikkeling,
verleen moontlik weerstandbiedendheid teen koueskade aan hierdie kultivar tydens langtermyn
koelkopbering.
Tydens opberging by -0.5 °C het koueskade ontwikkeling vinniger toegeneem, was
etileenvrystellingstempos hoër en die wateroplosbare antioksidantaktiwiteit (HAA), askorbiensuuren
glutatioonkonsentrasies en die MOV:POV verhouding laer in H2 (meer volwasse) ‘Sapphire’
pruime as in die H1 vrugte (minder volwasse). Dus, tesame met die laer antioksidantkonsentrasies
in die H2 vrugte om die vry radikale veroorsaak deur koelopbering te verminder, was hul
selmembrane ook meer vatbaar vir oksidasie a.g.v. die vetsuursamestellling van hul
membraanfosfolipiede. Die H2 vrugte het ook ‘n hoër konsentrasie van versadigde vetsure, en dus
minder vloeibare membrane as die H1 vrugte gehad tydens opberging by -0.5 °C.
Die dubbeltemperatuurregime (DT) het simptoomontwikkeling vertraag en koueskade-intensiteit
betekenisvol verminder in vergelyking met pruime wat by -0.5 °C opgeberg is. Vrugte wat met die
DT regime opgeberg is, het ‘n meer optimale fosfolipiedvetsuursamestelling en laer konsentrasie
van membraansterole tydens gesimuleerde raklewe gehad wat meer vloeibare membrane
verseker het. Hierdie behandeling het ook hoër HAA en lipiedoplosbare antioksidantaktiwiteit
(LAA), askorbiensuur- en glutatioonkonsentrasies gehad wat die vrugte beskerm het teen
oksidatiewe druk.
Verhoogde opbergingstemperature het hoër vlakke van lipiedperoksidasie of lae
askorbiensuurkonsentrasies asook swak vrugkwaliteit in ‘Sapphire’ pruime veroorsaak in
vergelyking met die DT regime. ‘Laetitia’ pruime wat by 5 °C en 7.5 °C opgeberg is, het
betekenisvol minder koueskade gehad in vergelyking met die DT regime, maar het vinniger sag
geword a.g.v. hoër etileenvrystellingstempos.
‘Sapphire’ kon lang en kort GLV tye weerstaan, maar ‘n stadiger inisiële GLV spoed het die
manifestasie van koueskade voorkom en het ‘n hoër HAA in die vrugte tot gevolg gehad na
koelopberging. ‘Laetitia’ wat met ‘n stadiger inisiële GLV spoed en oor ‘n langer tyd verkoel is, het
die beste vrugkwaliteit, en hoër HAA, totale fenool-, fosfolipied- en versadigde
fosfolipiedvetsuurkonsentrasies as die ander behandelings tydens koelopberging gehad
|
4 |
Moisture loss studies in Japanese plums (Prunus salicina Lindl.)Theron, Jacobus Adriaan 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The export of Japanese plums from South Africa is challenging. Exporting late season plums require fruit to last as long as 8 weeks in cold-storage. Prolonged storage periods can cause some cultivars to develop a shrivelled appearance due to moisture loss. Moisture loss from perishable commodities manifests mainly as shrivelling due to a loss in the turgidity of the surface cells of the fruit, or weight loss.
‘African DelightTM’ (highly susceptible to shrivel), ‘Laetitia’ (shrivel susceptible), ‘Sapphire’ (shrivel susceptible) and ‘Songold’ (not shrivel susceptible) plums were investigated by means of fluorescent microscopy for cracks and openings in the fruit peel. Only ‘African DelightTM’ had open hairline cracks in its peel, and fruit with wider cracks were associated with higher water vapour permeabilities. Open lenticels were found in the peels of ‘African DelightTM’, ‘Laetitia’ and ‘Sapphire’ plums. For ‘Songold’ no peel cracking or open lenticels were observed. The fact that the cuticle of this cultivar is mostly intact may be the reason why it is not susceptible to postharvest shrivel manifestation.
The water vapour permeance of the fruit peel determines how easily fruit lose moisture. In this study it was determined to what extent fruit, trees, orchards, harvest date and cultivar contribute to the total variation in plum peel water vapour permeability. The permeabilities of ‘African DelightTM’, ‘Laetitia’, and ‘Songold’ were determined weekly from 4 weeks before harvest until post optimum maturity. Fruit to fruit variation made the largest contribution towards the total variation (> 45%), followed by harvest date (> 20%) and orchard (> 15%) effects. The permeability across all cultivars increased two-fold as fruit became over mature. The contribution of cultivar differences to fruit peel permeability varied greatly between seasons (42% in 2013/2014 and 5% in 2014/2015). Differences between cultivars may include cuticle thickness and composition, micro cracks in the peel and/or open lenticels.
Current handling protocols suggest that fruit should be cooled as soon as possible after harvest, but this is not always possible. ‘African DelightTM’ plums were exposed to various handling scenarios in order to determine the handling protocol with the least risk of moisture loss. The control consisted of packaging and cooling the fruit within 6 h of harvest. Fruit quality was comparable or even better than the control when the fruit were pre-cooled to 0 °C and 15 °C for up to 72 h. High vapour pressure deficits caused fruit to lose more moisture, especially when fruit were exposed to ambient temperatures for 48 h and 72 h. It is recommended that handling protocols for plums should be followed stringently in order to reduce mass loss and shrivel manifestation.
Since other studies found that silicate (Si) has positive effects on fruit quality, we applied potassium silicate preharvest to ‘African DelightTM’ trees. However, we did not find significant differences between treatments regarding crack width or crack incidence in the fruit peel, shrivel, decay, internal browning, gel breakdown or aerated tissue levels. Currently preharvest potassium silicate applications are not recommended to improve plum quality. / AFRIKAANSE OPSOMMING: Die uitvoer van die Japanese pruime uit Suid-Afrika is 'n uitdaging, omrede daar verwag word dat laatseisoen kultivars tot 8 weke in koelopberging moet bly. Lang opbergingsperiodes veroorsaak dat sommige kultivars 'n verrimpelde voorkoms ontwikkel a.g.v. vogverlies. Vogverlies uit vars produkte manifesteer hoofsaaklik as verrimpeling a.g.v. 'n verlies in die turgiditeit van die selle in en onder die vrugskil, en as massaverlies.
‘African DelightTM’ (hoogs vatbaar vir verrimpeling), ‘Laetitia’ (vatbaar vir verrimpeling), ‘Sapphire’ (vatbaar vir verrimpeling) en ‘Songold’ (nie vatbaar vir verrimpeling) pruime is ondersoek deur middel van fluoressensie mikroskopie vir krake en openinge in die vrugskil. Slegs ‘African DelightTM’ het oop haarlyn krake in sy skil gehad en vrugte met wyer krake het ʼn hoër waterdamp deurlaatbaarheid gehad. Oop lentiselle is gevind in die skille van ‘African DelightTM’, ‘Laetitia’ en ‘Sapphire’ pruime. ‘Songold’ het geen krake of oop lentiselle getoon nie. Die feit dat ‘Songold’ se kutikula meestal ongeskonde was, mag die rede wees waarom hierdie kultivar nie vatbaar vir verrimpeling is nie.
Die waterdamp deurlaatbaarheid van 'n vrugskil bepaal hoe maklik vrugte vog verloor. In hierdie studie is bepaal tot watter mate vrugte, bome, boorde, oesdatum en kultivar bydra tot die totale variasie in die pruimskil se waterdamp deurlaatbaarheid. Die deurlaatbaarheid van ‘African DelightTM’, ‘Laetitia’, en ‘Songold’ is weekliks bepaal vanaf 4 weke voor die verwagte oesdatum tot die vrugte oorryp was. Vrug tot vrug variasie het die grootste bydrae tot die totale variasie gemaak (> 45%), gevolg deur oesdatum (> 20%) en boord (> 15%). Die skildeurlaatbaarheid van al die kultivars het verdubbel in die tyd van net voor oes tot die vrugte oorryp was. Die kultivar se bydrae tot die deurlaatbaarheid van die vrugskil het baie gewissel tussen seisoene (42% in 2013/2014 en 5% in 2014/2015). Verskille in skil-deurlaatbaarheid tussen kultivars kan kutikula-dikte en -samestelling, mikro-krake in die skil en/of oop lentiselle insluit.
Huidige hanteringsprotokolle stel voor dat vrugte so spoedig moontlik afgekoel word na oes, maar dit is nie altyd moontlik nie. In hierdie studie is 'African DelightTM' pruime is blootgestel aan verskeie hantering scenario's om die hanteringsprotokol met die laagste risiko vir vogverlies te bepaal. Die kontrole vrugte is gepak en onder geforseerde verkoeling geplaas binne 6 ure na oes. Vrugkwaliteit was vergelykbaar of selfs beter in vergelyking met die kontrole wanneer die vrugte voorverkoel is tot 0 °C en 15 °C vir tot 72 uur. Hoë dampdrukverskille het veroorsaak dat vrugte meer vog verloor, veral wanneer vrugte aan kamertemperatuur blootgestel was vir 48 h en 72 h na oes. Dit word aanbeveel dat hanteringsprotokolle vir pruime streng gevolg moet word om massaverlies en verrimpeling te beperk.
Aangesien ander studies gevind het dat silikaat (Si) ‘n positiewe uitwerking op vrugkwaliteit het, het ons kaliumsilikaat vooroes aan ‘African DelightTM’ bome toegedien. Daar was egter geen beduidende verskille tussen behandelings met betrekking tot kraakbreedte of kraakvoorkoms in die vrugskil of t.o.v. gehalte eienskappe soos die voorkoms van verrimpeling, bederf, interne verbruining, gelverval of deurlugte weefsel nie. Tans word voor-oes kaliumsilikaat spuite nie aanbeveel om pruimkwaliteit te verbeter nie.
|
5 |
ESTUDO ANALÍTICO E AVALIAÇÃO DA ATIVIDADE ANTIBACTERIANA DA MISTURA DOS ÓLEOS ESSENCIAIS DE FRUTOS DE Pimenta dioica Lindl E DOS GALHOS DE Aniba duckei Kostermans / ANALYTICAL STUDY AND EVALUATION OF THE ANTIBACTERIAL ACTIVITY OF THE MIXTURE OF ESSENTIAL dioica Pimenta Lindl OILS FRUITS AND Aniba duckei Kostermans TWIGSPereira, Alvaro Itauna Schalcher 08 July 2009 (has links)
Made available in DSpace on 2016-08-19T12:56:32Z (GMT). No. of bitstreams: 1
ALVARO ITAUNA SCHALCHER PEREIRA.pdf: 1919061 bytes, checksum: b573938dd4b8e1b868b6c8080c436851 (MD5)
Previous issue date: 2009-07-08 / Plants are an important source of biologically active products, many of which are on models for the synthesis of new drugs. With the increase of the indiscriminate use of antibiotics, bacteria resistant to conventional antimicrobial therapy have emerged and the essential oils are mentioned as an alternative to the problem. This work is promoted the extraction of essential oils of Pimenta dioica Lindl species (fruit) and duckei Aniba Kostermans (branches), the method of hydrodistillation using a Clevenger and their mixture in equal parts. The species Aniba duckei Kostermans, last classification of pau rosa Amazon, is a native species in the Amazon region, the family of Lauráceas. You can reach 30m in height. The type of vegetation occurring is tropical moist forest and land. Its essential oil is used in perfumery because of its high content of linalool. The plant species Pimenta dioica Lindl, popularly known as allspice, is a tree 6 to 15 m in height and belongs to the family of Mirtaceae and is home to Central America and western India. In Brazil, the plant is found in large scale in the State of Bahia and Recife. Its fruit contains an essential oil of great economic value in the international market due to high content of eugenol which is widely used in the chemical and pharmaceutical industries. After extraction, the mixture of oils were characterized by the following physical parameters: density (25 ° C), solubility in 70% ethanol, a refractive index (ND 25), color, appearance and odor. Furthermore, it was possible, the techniques of UV-Vis spectrophotometry, gas chromatography and mass spectrometry to identify with certainty the linalool and eugenol as major constituents of the mixture of essential oils. In applying the mixture of essential oils and standards of eugenol and linalool as antimicrobial agents using the Kirby-Bauer method for the bacteria Bacillus cereus, Chromobacterium violaceum, Enterococcus faecalis, Listeria monocytogenes, Salmonella Thyphi, Serratia marcescens and antibiotics ampicillin, cefotaxime, cefoxitin, erythromycin, gentamicin, novobiocin, penicillin, tetracycline and vancomycin, for comparison. You can see that the study of antimicrobial activity showed that the mixture of essential oils showed excellent activity against all bacteria tested, with the eugenol and linalool are the main responsible for this effectiveness. In this research we observed that the blend of essential oils is more efficient than the standards of eugenol and linalool and the antibiotics tested for the pathogen Listeria monocytogenes, Enterococcus faecalis, Chromobacterium violaceum. For Bacillus cereus, Serratia marcescens and Salmonella Thyphi the mixture was not more effective than the antibiotics Tetracycline, Erythromycin, Cefoxitin, cefotaxime, ampicillin and penicillin. / As plantas são uma fonte importante de produtos biologicamente ativos, muitos dos quais se constituem em modelos para a síntese de novos fármacos. Com o aumento indiscriminado do uso de antibióticos, bactérias resistentes à terapia antimicrobiana convencional têm surgido e os óleos essenciais são apontados como alternativa para o problema. Neste trabalho promoveu-se a extração dos óleos essenciais das espécies Pimenta dioica Lindl (frutos) e da Aniba duckei Kostermans (galhos), pelo método de hidrodestilação, utilizando um sistema Clevenger e sua mistura em partes iguais. A espécie vegetal Aniba duckei Kostermans, última classificação do pau rosa amazônica, é uma espécie nativa da região amazônica, da família das Lauráceas. E pode atingir até 30m de altura. O tipo de vegetação onde ocorre é de floresta tropical úmida e terra firme. Seu óleo essencial é utilizado em perfumaria, devido ao seu alto teor de linalol. A espécie vegetal Pimenta dioica Lindl, conhecida popularmente como pimenta da jamaica, é uma árvore de 6 a 15 m de altura, e pertence à família das Mirtaceae e tem como origem a América Central e oeste da Índia. No Brasil, a planta é encontrada em grande escala no Estado da Bahia e Recife. Seu fruto contém um óleo essencial de grande valor econômico no mercado internacional, devido ao elevado teor de eugenol o qual é largamente usado nas indústrias químicas e farmacêuticas. Após a extração, a mistura dos óleos foram caracterizados pelos seguintes parâmetros físicos: densidade (25 ºC), solubilidade em etanol a 70%, índice de refração (ND 25º), cor, aparência e odor. Além disso, foi possível, pelas técnicas de espectrofotometria de UV-Vis, cromatografia gasosa e espectrometria de massas, identificar, com segurança o linalol e o eugenol como constituintes majoritários da mistura de óleos essenciais. Na aplicação da mistura de óleos essenciais e dos padrões de eugenol e linalol como agentes antimicrobianos, utilizou-se o Método de Bauer-Kirby para as bactérias Bacillus cereus, Chromobacterium violaceum, Enterococcus faecalis, Listeria monocytogenes, Salmonella Thyphi, Serratia marcescens e os antibióticos Ampicilina, Cefotaxima, Cefoxitina, Eritromicina, Gentamicina, Novobiocina, Penicilina, Tetraciclina e Vancomicina, para comparação. Pode-se perceber que o estudo da atividade antimicrobiana revelou que a mistura de óleos essenciais apresentou excelente atividade contra todas as bactérias testadas, sendo que o eugenol e o linalol são os principais responsáveis por esta eficácia. Nessa pesquisa observou-se que a mistura de óleos essenciais é mais eficiente que os padrões de Eugenol e Linalol e os antibióticos testados para os microrganismo Listeria monocytogenes, Enterococcus faecalis, Chromobacterium violaceum. Para o Bacillus cereus, Serratia marcescens e Salmonella Thyphi a mistura só não foi mais eficiente que os antibióticos Tetraciclina, Eritromicina, Cefoxitina, Cefotaxima, Ampicilina e Penicilina.
|
6 |
ESTUDO QUÍMICO E ATIVIDADE ANTIFÚNGICA DO ÓLEO ESSENCIAL DOS FRUTOS DA Pimenta dioica Lindl. / CHEMICAL STUDY AND ANTIFUNGAL ACTIVITY OF ESSENTIAL OIL FRUITS OF THE Pimenta dioica Lindl.B. Júnior, Francisco Reivilandio da S. 10 June 2011 (has links)
Made available in DSpace on 2016-08-19T12:56:37Z (GMT). No. of bitstreams: 1
Francisco Reivilandio.pdf: 1587328 bytes, checksum: 64f5702f7917c2248cddce09472cef03 (MD5)
Previous issue date: 2011-06-10 / Jamaican pepper, Pimenta dioica Lindl, is a species belonging to the family of Myrtacea,
measuring 6m to 15m high, very aromatic in all its parts. It is originally from Central America
and West India and with great economic importance in the market of essential oils. The
extraction of the essential oil of Pimenta dioica L seeds was carried out by using the method
of hydrodistillation known as Cleverger system. It was extracted from a maximum volume of
oil in the period of four hours with a yield of 2.8% m/m. The UV spectrophotometric
techniques, mass spectrometry and gas chromatography, as well as the physical constants,
density, color and appearance were used to identify the compound eugenol and other
constituents of the essential oil of P. dioica L. Through the technique of external standard and
standard addition it was quantified with a eugenol percentage of 76.98%, forming the major
component. The essential oil of Pimenta dioica L was applied to the phyto pathogenic fungi
species Fusarium oxysporum f. sp. lycopersici, Fusarium oxysporum f. sp. passiflorae,
Fusarium subglutinans f. sp ananas., Fusarium oxysporum f. sp. vasinfectum and Fusarium
oxysporum f. sp. cubense resulting in a total inhibition of mycelial growth of all species tested
for a period of ten days of evaluation. / A pimenta da Jamaica, Pimenta dioica Lindl, é uma espécie vegetal pertencente à família
Mirtacea, medindo de 6 a 15 m de altura, muito aromática em todas as suas partes. É
originaria da América Central e Oeste da Índia e com grande importância econômica no
mercado de óleos essenciais. A extração do óleo essencial das sementes da P. dioica foi
realizada pelo método da hidrodestilação utilizando o sistema Cleverger. Foi extraído um
volume máximo de óleo no tempo de quatro horas com um rendimento de 2,8 %m/m. As
técnicas espectrofotométricas de UV, espectrometria de massa e cromatografia gasosa, assim
como as constantes físicas, densidade, cor e aparência foram utilizadas para identificar o
composto eugenol e os demais constituintes do óleo essencial da P. dioica. Através da técnica
de padrão externo e adição de padrão quantificou-se o eugenol com um percentual de 76,98
%, constituindo-se o componente majoritário. O óleo essencial da P. dioica foi aplicado em
fungos fitopatogênicos das espécies Fusarium oxysporum f. sp. lycopersici, Fusarium
oxysporum f. sp. passiflorae, Fusarium subglutinans f. sp. ananas, Fusarium f. sp.
vasinfectum e Fusarium oxysporum f. sp. cubense, obtendo-se uma inibição total do
crescimento micelial de todas as espécies testadas por um período de dez dias de avaliação.
|
7 |
Phenolic composition and in vitro antioxidant capacity of South African plums (Prunus salicina Lindl.)Venter, Alet 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Phenolic compounds of the types present in plums have been found to exhibit health-promoting properties associated with their antioxidant capacity. Fruits with red peel and/or flesh are thus sought-after for their high antioxidant levels. In the current study South African plum (Prunus salicina Lindl.) cultivars and selections, harvested during two consecutive fruit seasons, were compared in terms of general fruit attributes (colour, firmness, °Brix, pH, titratable acidity), phenolic composition and antioxidant capacity. The effect of season and a commercial cold storage and ripening regime was also investigated.
A reversed-phase high-performance liquid chromatography-diode-array-fluorescence detection (HPLC-DAD-FLD) method suitable for use with mass spectrometry (MS) detection, was optimised for separation and identification of phenolic compounds from four phenolic groups (phenolic acids, anthocyanins, flavan-3-ols and flavonols) in six South African plum cultivars and five selections. Parameters that were optimised include the mobile phases, analysis temperature and gradient program. Good stability, linearity and inter- and intra-day precision were obtained. Identification of compounds was based on comparison of retention times, UV-Vis spectra and mass fragments with available authentic phenolic standards and/or literature data. The optimised method allowed identification or tentative identification of twenty-four phenolic compounds, including cyanidin-3-O-glycosides, quercetin glycosides, monomeric, dimeric and trimeric flavan-3-ols, and hydroxycinnamic acids. An on-line ABTS•+ (2,2ʹ-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid)) antioxidant assay, performed for qualitative evaluation of the antioxidant response of individual phenolic compounds, indicated the flavan-3-ols as major antioxidants in plums.
Eighteen phenolic compounds were quantified, including anthocyanins and flavonol glycosides, flavan-3-ols (monomers and dimers) and hydroxycinnamic acids. Phenolic composition differed greatly between cultivars and selections. Cyanidin-3-O-glucoside was the predominant anthocyanin in plums with red peel and/or flesh, followed by cyanidin-3-O-rutinoside. Cyanidin-3-O-galactoside was present only in the cultivar Laetitia (red peel, yellow flesh). The ripe fruit of Ruby Red and PR04-19, both with red peel and flesh, had the highest anthocyanin content for the first and second harvest season, respectively. Neochlorogenic acid and quercetin-3-O-glucoside were the major phenolic acid and flavonol, respectively. Chlorogenic acid, 3-O-p-coumaroylquinic acid and several quercetin-glycosides and -diglycosides were also present in some cultivars and selections. Procyanidin B1 was the flavan-3-ol present in the highest concentration in the majority of cultivars and selections and its content correlated with the (+)-catechin content, while the same was observed for procyanidin B2 and (-)-epicatechin.
The effect of cold storage and ripening on fruit attributes differed greatly between cultivars and selections. The increase and decrease in pH and titratable acidity, respectively, were as expected for ripe fruit as opposed to unripe fruit. Ripe fruit had higher a*-values and lower L*-values. The cold storage and ripening regime had no significant effect on total polyphenol and total flavan-3-ol content of the cultivars and selections, but the anthocyanin content increased in some cases.
In terms of in vitro antioxidant capacity, the selections PR04-32 and PR04-35, both with red peel and flesh, had the highest antioxidant capacity, irrespective of assay. Sapphire (red peel, yellow flesh), with the lowest total polyphenol content, also had the lowest antioxidant capacity in the ORAC and FRAP assays. Both the total polyphenol and flavan-3-ol contents correlated significantly to antioxidant capacity, irrespective of assay. / AFRIKAANSE OPSOMMING: Fenoliese verbindings, soos teenwoordig in pruime, is bekend vir hul gesondheidsbevorderende eienskappe wat geassosieer word met antioksidant kapasiteit. Vrugte met ‘n rooi skil en/of vleis is veral gesog as gevolg van hul hoë antioksidant aktiwiteit. Met hierdie studie is Suid-Afrikaanse pruim (Prunus salicina Lindl.) kultivars en seleksies, geoes tydens twee opeenvolgende seisoene, vergelyk in terme van algemene vrug einskappe (kleur, fermheid, °Brix, pH en titreerbare suurheid), fenoliese samestelling en antioksidant kapasiteit. Die effek van ‘n kommersiële koelopberging en rypwording prosedure is ook ondersoek.
‘n Omgekeerde-fase hoë-druk vloeistof chromatografie (HPLC) metode met diode-opstelling en fluoressensie deteksie, maar wat ook geskik is vir massa spektrometrie (MS), is geoptimiseer om fenoliese verbindings te skei en te identifiseer in Suid-Afrikaanse pruime. Verbindings van vier fenoliese groepe (fenoliese sure, antosianiene, flavan-3-ole en flavonole) wat in ses kultivars en vyf seleksies voorgekom het, is ondersoek. Die vloeistof fases, skeidingstemperatuur en gradiënt van die metode is geoptimiseer. Goeie resultate vir stabiliteit, lineariteit en inter- en intra-dag akkuraatheid is verkry. Verbindings is geïdentifiseer deur vergelyking van retensie tye, UV-Vis spektra en massa fragmente met dié van egte fenoliese standaarde en/of met literatuur data. Vier-en-twintig fenoliese verbindings is geïdentifiseer of voorlopig geïdentifiseer, insluitende sianidien- en kwersetien glikosiede, flavan-3-ol monomere, dimere en trimere, en hidroksikaneelsure. ‘n Aanlyn ABTS•+ (2,2 ʹ-azino-di-(3-etielbensotialosien-sulfoon suur) radikaal katioon blussingstoets is gebruik om die antioksidant reaksie van individuele polifenole op ‘n kwalitatiewe wyse te evalueer en flavan-3-ole is as hoof antioksidante in pruime aangetoon. Kwantifisering van agtien verbindings, insluitende antosianiene, flavonol glikosiede, flavan-3-ole (monomere en dimere) en hidroksikaneelsure, was moontlik met hierdie geoptimiseerde metode. Die fenoliese samestelling het aansienlik verskil tussen kultivars en seleksies. Sianidien-3-O-glukosied was die hoof antosianien in pruime met ‘n rooi skil en/of vleis, gevolg deur sianidien-3-O-rutinosied. Sianidien-3-O-galaktosied het slegs in Laetitia (rooi skil en geel vleis) voorgekom. Ryp vrugte van Ruby Red en PR04-19, beide met rooi skil en vleis, het onderskeidelik die hoogste antosianieninhoud gehad met die eerste en tweede seisoen se oeste. Neochlorogeniese suur en kwersetien-3-O-glukosied was die hoof fenoliese suur en flavon-3-ol, onderskeidelik. Chlorogeniese suur, 3-O-p-kumarienkwiniensuur en verskeie kwersetien glikosiede en diglikosiede was teenwoordig in sekere kultivars/seleksies. Die flavan-3-ol, prosianidien B1, was teenwoordig in die hoogste konsentrasie in die meerderheid kultivars/seleksies. Die prosianidien B1 inhoud het met die (+)-katekien inhoud gekorreleer, terwyl dieselfde gevind is vir prosianidien B2 en (-)-epikatekien.
Die effek van koelopberging en rypwording op die algemene vrug einskappe het tussen kultivars en seleksies verskil. Die pH en titreerbare suurheid het onderskeidelik toegeneem en afgeneem, soos verwag is vir ryp vrugte teenoor onryp vrugte. Ryp vrugte het hoër a*-waardes en laer L*-waardes getoon. Koelopberging en rypwording het geen beduidende effek op die totale polifenol- en totale flavan-3-ol inhoud gehad nie, maar die antosianieninhoud het vir sommige kultivars en seleksies toegeneem.
In terme van in vitro antioksidant kapasiteit het die seleksies PR04-32 en PR04-35, beide met rooi skil en vleis, die hoogste antioksidant kapasiteit getoon, ongeag die antioksidant toets wat gebruik is. Sapphire (rooi skil en geel vleis) het die laagste totale polifenolinhoud gehad, asook die laagste antioksidant kapasiteit soos bepaal deur die ORAC en FRAP toetse. Beide die totale polifenol- en flavan-3-ol inhoud het beduidend met die antioksidant kapasiteit korreleer, ongeag van die toets wat gebruik is.
|
8 |
A study of broken stones in Japanese plums (Prunus salicina Lindl.)Kritzinger, Imke 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In order to export South African plums to overseas markets strict quality standards must be maintained. Among these quality classifications are specifications about the presence of cavities and pieces of broken stone/pit within the flesh of the fruit. If more than 10% of the fruit in a carton are affected by severely broken stones or large flesh cavities, the fruit have to be marketed as Class 2. A substantial amount of plums destined for export from South Africa is affected by broken stones and thus have to be marketed as Class 2. Lower prices are attained for Class 2 fruit, therefore, the presence of broken stones has a detrimental effect on the income generated from these fruit.
The main aim of this study was to gain a better understanding of broken stone development and compare the growth characteristics of Japanese plum cultivars differing in their susceptibility to broken stones.
Stone breakage in ‘Laetitia’ was observed as soon as stone hardening was initiated. At the start of stone hardening the parts of the stone that are still ‘soft’ are not strong enough to resist the pulling forces of the growing mesocarp and the stone is subsequently pulled apart. Regression analysis indicated that lengthwise growth of the fruit, fresh weight of the endo- and mesocarp, minimum orchard temperature and orchard night temperature, and relative humidity (RH) early in the growing season could possibly be used to predict the incidence of broken stones at harvest.
Differences in the incidence of broken stones were observed between ‘Laetitia’, ‘Sapphire’ and ‘Songold’ plums and between seasons. Furthermore, significant differences were observed in the density of the endocarp in different parts of the stone. For ‘Laetitia’ and ‘Songold’, stone breakage was observed when rapid increases in stone density coincided with rapid increases in fruit growth. The stones broke in positions where an interface exists between high and low density parts in the stone and when rapid radial growth takes place in the direction where the stone is least dense. In contrast, in ‘Sapphire’, stone breakage was observed before the stones had started to lignify, indicating that the endocarp was pulled apart by the expanding flesh because it was too soft to withstand the strong pulling forces created by the flesh. The incidence of broken stones was influenced by environmental factors, as higher temperatures during the stone development and hardening period could lead to more complete endocarp formation (more stone cells are formed under such conditions). Such fruit would thus have higher endocarp density, which, if coupled with rapid radial growth, could lead to a higher incidence of broken stones.
Foliar and/or root applications of calcium nitrate and potassium silicate were applied to ‘Laetitia’ plums to determine whether the incidence of broken stones could be reduced by increasing the strength of the endocarp cell walls. However, no such effect was observed. Hence, neither calcium nor silicate treatments can be recommended for reducing broken stones in plums. / AFRIKAANSE OPSOMMING: Om Suid-Afrikaanse pruime na oorsese markte uit te voer moet vrugte aan streng kwaliteitstandaarde voldoen. Daar is ondermeer spesifikasies in verband met die teenwoordigheid van holtes en stukkies gebreekte pit binne die vrug. Indien meer as 10% van die vrugte in ʼn karton deur ernstige gebreekte pit of groot vrugholtes geaffekteer word, moet die vrugte as Klas 2 bemark word. Aangesien ʼn groot hoeveelheid van die pruime wat vir uitvoer bestem is, geaffekteer word deur gebreekte pit en gevolglik as Klas 2 bemark moet word, word aansienlike finansiële verliese gelei. Laer pryse word behaal vir Klas 2 vrugte, en dus het die teenwoordigheid van gebreekte pitte ʼn negatiewe effek op die wins wat deur die uitvoer van hierdie vrugte gegenereer kan word.
Die hoofdoel van hierdie studie was om die ontwikkeling van gebreekte pit in Japannese pruime te ondersoek en om die groei-patrone van kultivars wat geneig is tot gebreekte pit te vergelyk met ʼn nie-sensitiewe kultivar.
Gebreekte pit in ‘Laetitia’ is opgemerk sodra die pit begin verhard het. Met die aanvangs van pit- verharding is die gedeeltes van die pit wat nog nie volkome verhard het nie, nie sterk genoeg om die sterk trekkragte van die groeiende mesokarp te weerstaan nie en die pit word gevolglik uitmekaar- getrek. Regressie-analise het gewys dat lengtegroei van die vrugte, vars massa van die endo- en mesokarp, minimum boordtemperatuur en boord-nagtemperatuur, asook relatiewe humiditeit gedurende die vruggroei-periode moontlik gebruik kan word om die voorkoms van gebreekte pit by oes te voorspel.
Verskille in die voorkoms van gebreekte pit is opgemerk tussen ‘Laetitia’, ‘Sapphire’ en ‘Songold’ pruime, en ook tussen seisoene. Verder is beduidende verskille opgemerk in die digtheid van die endokarp in verskillende dele van die pit. By beide ‘Laetitia’ en ‘Songold’ is gebreekte pit opgemerk wanneer vinnige toename in pit-digtheid saamgeval het met ʼn vinnige toename in vruggroei. Die pitte breek veral in die oorgang tussen dele van die pit met hoë en lae digtheid en as dit gekombineer is met vinnige radiale vruggroei in die rigting waar die pit die minste dig is. In teenstelling hiermee is gebreekte pit in ‘Sapphire’ opgemerk selfs voordat die pitte begin verhard het. Dit dui daarop dat die endokarp uitmekaargetrek is deur die vinnig groeiende mesokarp, omdat dit te sag was om die trekkragte van die groeiende vrugvlees te weerstaan. Die voorkoms van gebreekte pit word ook deur weerstoestande beïnvloed, want hoër temperature gedurende die pit-ontwikkeling en verhardingsperiode, kan lei tot die ontwikkeling van endokarpe met meer steenselle. Hierdie vrugte sal dus ʼn hoër digtheid hê, en as dit saamval met vinnige radiale groei, kan dit lei tot ʼn groter voorkoms van gebreekte pit.
Blaar- en/of worteltoedienings van kalsiumnitraat en kaliumsilikaat is gemaak om te bepaal of die voorkoms van gebreekte pit in ‘Laetitia’ verminder kon word deur die versterking van die endokarp-selwande. Geen van hierdie behandelings het tot ʼn vermindering in gebreekte pit gelei nie en nie kalsiumnitraat of kaliumsilikaat kan dus aanbeveel word om gebreekte pit in pruime te verminder nie.
|
9 |
Genetické aspekty domestikačního znaku pukavosti lusku u hrachuSmutná, Lenka January 2015 (has links)
At the beginning, the plant domestication was probably a non-conscious process. Later, it changed to a targeted process, when the cultural crops were developed from wild species due to human activities. Some crops occurred as a weed of the first cultural species in the past and were selected for individual crops during the domestication. The very beginning of the domestication can be found in neolithic era, when humans chan- ged their way of life from picking & hunting to agriculture & shepherdy. Change of climate after the last ice age was probably one of the reasons. Wild plants as a whole differ from cultural crops in set of domestication characters. Domesticated crops have for example bigger fruits (tomato plant - Solanum lycopersicum L.), contain lower amount of toxic substances (solanine, potato - S. tuberosum L.), natural spreading of seeds and dormancy were inhibited (pea - Pisum L.) etc. Spontaneous releasing of seeds was a big issue already in the past, and is a big issue also now. Afford to avoid this behavior was exerted from the beginning of agriculture. Plants developed various mechanisms of seed spreading into their surroundings for the purposes of species preservation. Legumes developed explosive seed spreading. Shrinking pod valves exert tension on both junctions and once the critical force was reached, the pod suddenly opens. During this action, the pod orientation changes (the tip obliquely upwards) and the seeds are catapulted up to several meters into surroundings. The objective of this work was to narrow mapping interval of the pod shattering ge- ne (Dpo1) in pea (Pisum L.) and focus on evaluation of phenotype of recombinant in- bred lines (RILs). Several RILs formed by crossbreeding of contract parent genotypes of P. elatius were used Steven ex M. Bieb. JI64 × clutural pea P. sativum L. JI92 and reci- procal crossbreeding JI92 × JI64; P. elatius Steven ex M. Bieb. VIR320 × cultural pea P. sativum L. WL1238. Next objective was a comparison anatomical analysis of pod structure in the area of ventral and dorsal junction and endocarp structure.
|
10 |
Doses e modos de aplicação de boro na produção de mudas de nespereira / Dosages and modes of application of boron in the production of seedlings loquat treePenha, Estevan Teodoro Santana [UNESP] 23 February 2016 (has links)
Submitted by ESTEVAN TEODORO SANTANA PENHA null (estevaneafmuz@yahoo.com.br) on 2016-03-21T13:30:08Z
No. of bitstreams: 1
Doses e modos de aplicação de boro na produção de mudas de nespereira - Estevan Teodoro Santana Penha.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-22T17:02:26Z (GMT) No. of bitstreams: 1
penha_ets_me_jabo.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5) / Made available in DSpace on 2016-03-22T17:02:26Z (GMT). No. of bitstreams: 1
penha_ets_me_jabo.pdf: 676725 bytes, checksum: 6294e21c7555edb90fa9a7510f640f10 (MD5)
Previous issue date: 2016-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The loquat cultivation is increasing in Brazil and in the world and is an important source of income for small farms, however, the production of seedlings can be an obstacle to its expansion. Thus the aim of this study was to evaluate Boron reflection on the quality of loquat seedlings, and the place of supply to plants parent by determining the most effective application method in this process. There were four boron doses (0, 2.5, 5.0 and 7.5 mg dm-3) and two application sites (soil and leaf). The use of boron instock plants improves the root system of plants from cuttings, the most efficient foliar application than the soil. The application of this micronutrient promotes balance between root / shoot, ensuring the formation of a balanced changes, given that the leaf supply increases the volume of the stake roots. Therefore the supply of boron to headquarters makes the process effectively, reducing cost, optimizing time and assuring the quality of fruit seedlings. / O cultivo de nêsperas vem aumentando no Brasil e no mundo, sendo uma importante fonte de renda para pequenas propriedades, no entanto, a produção de mudas pode ser um gargalo de sua expansão. Dessa forma o objetivo do presente trabalho foi avaliar o reflexo do boro na qualidade das mudas de nespereira, bem como o local de seu fornecimento às plantasmães determinando-se o modo de aplicação mais eficiente neste processo. Foram utilizadas quatro doses de boro (0; 2,5; 5,0 e 7,5 mg dm-3 ) e dois locais de aplicação (no solo e foliar). A utilização de boro nas plantas-matrizes melhora o sistema radicular das mudas obtidas por estaquia, sendo a aplicação foliar mais eficiente do que via solo. A aplicação deste micronutriente promove o equilíbrio entre raiz/parte aérea, garantindo a formação de uma muda equilibrada, haja vista que o fornecimento foliar aumenta o volume de raízes da estaca. Portanto o fornecimento de boro às matrizes torna o processo eficaz, reduzindo custo, otimizando tempo e garantindo a qualidade das mudas frutíferas.
|
Page generated in 0.0316 seconds