O cultivo de fisális (Physalis peruviana L.) é uma alternativa promissora para os agricultores que se dedicam à produção de frutíferas exóticas, do segmento de \"pequenas frutas\", em decorrrência da valorização do fruto, que possue diversas qualidades organolépticas e funcionais. Entretanto, ainda são escassas as informações sobre a cultura nas condições edafoclimáticas brasileiras, especialmente em relaçao aos processos de maturação dos frutos e das sementes, de modo que possa ser indicado o momento adequado para a colheita, considerando a qualidade dos frutos e das sementes e, não menos importante, o estudo das condições ideais para o teste de germinação das sementes, uma vez que, este teste, além de ser empregado para auxiliar na identificação da maturidade fisiológica das sementes, seus resultados são parâmetro para comparação da qualidade das sementes dos lotes e para a comercialização das sementes. Portanto, a presente pesquisa foi realizada com os objetivos de avaliar as necessidades de luz, temperatura e substrato para o teste de germinação; estudar a maturação dos frutos e das sementes e, a incidência de fungos nas sementes de Physalis peruviana L., segundo o momento do florescimento da planta e a idade dos frutos. Desta forma, a pesquisa foi conduzida entre fevereiro de 2016 e novembro de 2017, nos Laboratórios Análise de Sementes (LAS), de Análise de Imagens (LAI), de Pós-Colheita de Produtos Hortícolas (LPCPH) e de Patologia de Sementes (LPS), pertencentes aos Departamentos de Produção Vegetal e de Fitopatologia e Nematologia, da Escola Superior de Agricultura \"Luiz de Queiroz\", Universidade de São Paulo (USP, ESALQ), em Piracicaba, São Paulo. Para os estudos do teste de germinação das sementes, primeirameite foram avaliados diferentes suprimentos de luz e temperatura, sendo utilizada uma mesa termogradiente regulada com nove intervalos de temperatura (variação de 15 °C a 35 °C) e duas alternadas 20-30 °C e 15-35 °C, com oito horas de fotoperíodo e na ausência total de luz. Após estabelecidos os requerimentos de luz e temperatura, foram estudados os substratos para germinação das sementes: papel mata-borrão (sobre papel), areia (entre areia) e vermiculita (entre vermiculita). Quanto aos estudos da maturação e análise sanitária, foram distinguidos dois momentos de florescimento das plantas, 55 e 105 dias após o transplante (DAT) e, em cada um destes momentos, as flores foram marcadas por ocasião da antese e os respectivos frutos e sementes avaliados aos 45, 60, 75 e 90 dias após (DAA). A germinação das sementes de Physalis peruviana L. ocorre em intervalo amplo de temperatura (15 a 30,2 °C), sendo ideais as temperaturas 25 °C constante e 20-30 °C alternada, com oito horas de luz. O substrato areia (entre areia) é mais adequado e, como alternativa, podem ser utilizados o papel (sobre papel) e a vermiculita (entre vermiculita). As avaliações do teste de germinação podem ser realizadas no 7º dia (primeira contagem) e no 14º dia (contagem final) após a instalação do teste. O momento do florescimento e o estádio de desenvolvimento do fruto têm influência sobre as características qualitativas deste e sobre a maturação das sementes. A idade (em dias após a antese) e as modificações da cor, da massa, do tamanho e do sabor que ocorrem durante o desenvolvimento são parâmetros indicativos da maturidade fisiológica tanto do fruto quanto das sementes, as quais ocorrem aos 75 DAA (55 DAT) e aos 60 DAA (105 DAT). Além disso, os frutos produzidos em Piracicaba, São Paulo, têm padrão para a comercialização e qualidade similar a dos frutos produzidos em outras regiões de cultivo. Os gêneros fúngicos constatados em sementes de Physalis peruviana L. são Alternaria, Aspergillus, Bipolaris, Cladosporium, Epicoccum, Fusarium, Nigrospora e Penicillium, sendo a menor incidência em sementes de 75 DAA. A presença dos fungos não afeta o componente fisiológico das sementes. / The cultivation of cape gooseberry (Physalis peruviana L.) is a promising alternative for the farmers who are dedicated to the production of exotic fruit, the \"small fruits\" segment, due to the valorization of the fruit, which has several organoleptic and functional qualities. However, information about the crop under Brazilian soil and climate conditions is still scarce, especially in relation to the fruit and seed maturation processes, so that the appropriate time for harvest can be indicated, considering the quality of the fruits and seeds and, not least, the study of the ideal conditions for the seed germination test, since this test, besides being used to help in the identification of the physiological maturity of the seeds, yours results are parameter for comparison the seed quality of the lots and for seed marketing. Therefore, the present research was developed out with the objective of evaluating the light, temperature and substrate requirements for the germination test and to study the maturation of fruits and seeds, and the incidence of fungi on seed of Physalis peruviana L., according to the moment of flowering of the plant and fruit age. The research was conducted between february 2016 and november 2017, in the Laboratories of Seeds Analysis (LAS), Analysis of Images (LAI), Post-Harvesting of Horticultural Plants (LPCPH) and Pathology Seeds (LPS), belonging to the Departments of Crop Science and Phytopathology and Nematology, Luiz de Queiroz College of Agriculture, University of São Paulo (USP/ESALQ), in Piracicaba, São Paulo. For the seed germination test, different light and temperature supplies were evaluated first, using a termo-gradient table regulated with nine temperature ranges (ranging from 15 °C to 35 °C) and two alternate 20-30 °C and 15-35 °C, with eight hours of photoperiod and in the total absence of light. After the light and temperature requirements were established, the substrates for seed germination were studied: blotter paper sheets (upon paper), sand (between sand) and vermiculite (between vermiculite). In the maturation and seed health studies, two flowering moments were considered, at 55 and 105 days after transplanting (DAT) of the plants, and in each of these moments, the flowers were marked in the anthesis and the respective fruits and seeds evaluated at 45, 60, 75 and 90 days after anthesis (DAA).The germination of the seeds of Physalis peruviana L. occurs in a wide temperature range (15 to 30,2 °C), with temperatures 25 °C constant and 20-30 °C alternating, with eight hours of light. The sand substrate (between sand) is more suitable and, alternatively, paper and vermiculite may be used. The germination test evaluations can be performed on the 7th day (first count) and on the 14th day (final count) after the test installation. The moment of flowering and the development stage of the fruit influence the qualitative characteristics of the fruit and the maturation of the seeds. The age (in days after anthesis) and changes in color, mass, size and flavor that occur during the development, are indicative parameters of the physiological maturity of both fruit and seeds, which occur at 75 DAA (55 DAT) and at 60 DAA (105 DAT). In addition, fruits produced in Piracicaba, São Paulo, has a commercial pattern and quality similar to the fruits produced in other regions. The fungal genus found in seeds of Physalis peruviana L. are Alternaria, Aspergillus, Bipolaris, Cladosporium, Epicoccum, Fusarium, Nigrospora and Penicillium, the lowest incidence occurring in seeds of 75 DAA. The presence of fungi does not affect the physiological component of the seeds.

Made available in DSpace on 2017-07-25T19:29:46Z (GMT). No. of bitstreams: 1 Emanuela Mariano.pdf: 305473 bytes, checksum: 0a163df926b6d1a6ea64912fc08c50de (MD5) Previous issue date: 2008-12-15 / Knowing about the perishability of the persimmon, the raising of the production and the high losses after harvest of this product it was needed to evaluate the effect of the after harvest treatment in water solution of resveratrol. The research was done at the University of Ponta Grossa Vegetable Biotechnology Lab in april/march of 2007. The fruits were immerse during five seconds in water solution of resveratrol in doses of 1000;2000 and 3000 mg.L-¹ to cultivate Fuyu and in doses of 4000;5000 and 6000 mg.L-¹ to cultivate Giombo. The fruits were stocked in a cold chamber at 0±2º C and ur 95±2%. The Fuyu fruits stood stocked for 0;15;30 and 45 days and the Giombo fruits for 0; 7; 15; 21 and 28 days and then took off refrigeration and maintaned for 2 days in a aclimation chamber at 25ºC to simulate the comercial environment. The fruits were evaluated on weight loss, fortitude, total soluble solids, pulp Ph, total acidity and vitamin C. It was observed that the resveratrol didn't preserve the pulp fortitude and didn't maintain the Giombo or Fuyu fruits weight. The soluble solids grade varied from 16 to 22ºBrix and the acidity of the fruits varied from Fuyu to Giombo. The pH value from the Giombo fruits stayed in the range of 5,13 to 5,54 , and the Fuyu fruits between 5,0 and 5,92. The resveratrol treatment affected in a negative way the vitamin C grades. / Tendo em vista a alta perecebilidade do fruto de caqui, o aumento crescente da produção e as elevadas perdas pós-colheita deste pro uto objetivou-se avaliar o efeito do tratamento póscolheita em solução aquosa de resveratrol. O trabalho foi conduzido no Laboratório de Biotecnologia Vegetal da Universidade Estadual de Ponta Grossa em abril/maio de 2007. Os frutos foram imersos durante cinco segundos em solução aquosa de resveratrol nas doses de 1000; 2000 e 3000 mg.L-1 para a cultivar Fuyu e nas doses de 4000; 5000 e 6000 mg.L-1 para a cultivar Giombo. Os frutos foram armazenados em câmara fria a 0±2oC e UR 95±2%. Os frutos da cultivar Fuyu permaneceram armazenados por 0; 15; 30 e 45 dias e da cultivar Giombo por 0; 7; 15; 21 e 28 dias e então retirados da refrigeração e mantidos por 2 dias em câmara de aclimatação à 25oC a fim de simular o ambiente de comercialização. Os frutos foram avaliados com relação à perda de massa, firmeza, sólidos solúveis totais, pH da polpa, acidez total titulável e vitamina C. Observou-se que o resveratrol não preservou a firmeza da polpa e nem manteve o peso dos frutos de caqui das cultivares Giombo e Fuyu. O teor de sólidos solúveis variou de 16 a 22 oBrix e a acidez dos frutos de caqui variou em função da cultivar. Os valores de pH dos frutos de caqui cultivar Giombo permaneceram na faixa de 5,13 a 5,54, e para a cultivar Fuyu entre 5,0 e 5,92. O tratamento com resveratrol afetou negativamente os teores de vitamina C.

A nespereira é uma planta rústica, que prescinde da utilização sistemática de defensivos, o que torna o cultivo atraente, para atender ao público que cresce, dia a dia, à procura de produtos naturais.O trabalho teve por objetivo realizar a caracterização fenológica da nespereira, estabelecendo os estádios fenológicos e o ciclo de produção de 5 cultivares e de uma seleção.Também estudou-se a melhor fase para o ensacamento dos frutos e a intensidade de raleio para a obtenção de frutos de alta qualidade. Foi estabelecida uma escala fenológica contendo sete estádios de desenvolvimento para a nespereira. Os estágios observados foram: 0 Desenvolvimento da Gema; 1 Desenvolvimento das folhas; 3 Desenvolvimento dos Brotos; 5 Emergência da Inflorescência; 6 Florescimento; 7 Desenvolvimento dos frutos; 8 Maturação dos frutos, de acordo com a escala BBCH. Mediante o estudo da escala fenológica das 5 cultivares e da seleção IAC NE3, verificou-se a existência de diferenças no ciclo de produção das cultivares estudadas e também da seleção, possibilitando a observação de três grupos. O primeiro grupo, mais precoce, foi formado pelas cultivares Mizuho e Mizumo, com ciclo médio de 195 dias contados a partir do início do desenvolvimento das gemas até a colheita dos frutos. As cultivares Néctar de Cristal e Centenária formaram um segundo grupo apresentando um ciclo intermediário com uma média de 203 dias. Já a cultivar Mizauto e a seleção IAC NE3 foram as mais tardias, uma vez que o ciclo foi concluído 208 dias, em média, após o início do desenvolvimento das gemas.A intensidade de raleio a ser adotada deve ser de 4 ou 6 frutos por panícula, levando-se em conta a safra esperada; o ensacamento dos frutos deve ser realizado nos estádios 1 (frutos com 1,0 cm de diâmetro) ou 2 (frutos com 1,5 cm de diâmetro). / The Loquat is a rustic plant, which renounce the systematic use of defensive, which makes the cultivation attractive, to attend the public that grows, day by day, the demand for natural products. The study aimed to carry out the phenological characterization of loquat, setting the phenological stages and the cycle of production of 5 cultivars and a selection. Also studied is the best stage for the bagging of panicles and thinning intensity for obtaining fruits of high quality. Was established a scale containing seven phenological stages of development for loquat. The stages were observed: 0 - Development of bud, 1 - Development of the leaves, 3 - Development of shoot, 5 - Emergency of Inflorescence, 6 - Blooming; 7 - Development of fruit; 8 - Ripening fruits, according to the scale BBCH. Through the study of phenological scale from 5 cultivars and selection IAC NE3, there are differences in the production cycle of cultivars and the selection, enabling the observation of three groups. The first group, earlier, was formed by cultivars with Mizuho and Mizumo cycle average of 195 days counted from the beginning of the development of buds until the harvest fruit. Cultivars nectar of Cristal and Centenária formed a second group presenting a cycle intermediary with an average of 203 days. The cultivar Mizauto and the select IAC NE3 were the most late, since the cycle was completed 208 days on average after the start of the development of buds. The intensity of thinning to be used must be 4 or 6 fruits per raceme, considering the crop waited and the fruit price in the market. The fruit bagging must be realized in the harvest time 1(fruits with 1,0 cm of diameter) or 2(fruits with 1,5 cm of diameter).

O estado de São Paulo destaca-se como o maior produtor nacional de banana (Musa spp.), com sua produção comercial tradicionalmente concentrada na região do Vale do Ribeira e no Litoral Paulista. No entanto, os cultivos se estenderam a partir da década de 1990 para o Planalto Paulista, onde agricultores buscavam uma maior diversificação das atividades agrícolas. A prevalência do cultivo com cultivares tradicionais tem sido desafiadora devido à suscetibilidade dessas às principais doenças. Objetivou-se avaliar dois novos híbridos tetraplóides (AAAB) resistentes à Sigatoka amarela (Mycosphaerella musicola, Leach), a \'BRS Platina\' e a \'BRS Princesa\', comparando-os com a cultivar comumente utilizada, a \'Prata-anã\' (AAB). No entanto, a adoção de novos híbridos de bananeira não se estabelece apenas pela sua resistência às doenças. Dessa forma, variáveis vegetativas, variáveis de rendimento do cacho e suas correlações, duração do ciclo e qualidade pós-colheita dos frutos também foram avaliadas. O experimento foi conduzido no município de Piracicaba-SP (latitude: 22 43\' 30\'\' S, longitude de 47 38\' 56\'\' O e altitude de 554 metros), que possui clima classificado como Cwa, com chuva predominante no verão e período mais seco e frio no inverno. O delineamento experimental foi o de blocos ao acaso, com a adoção de três repetições e a parcela composta por três plantas. Quanto às avaliações da qualidade pós-colheita dos frutos, o delineamento experimental adotado foi o inteiramente casualizado, 12 dias de armazenamento, três repetições, cada qual constituída por três frutos. Os resultados foram submetidos à análise estatística de variância e ao teste de Tukey a 5% de significância; análise de correlação com base na correlação de Pearson e análise de regressão a 5% de significância. De acordo com os resultados obtidos, conclui-se que as cultivares BRS Platina e BRS Princesa apresentam maior resistência à Sigatoka amarela em relação à cultivar Prata-anã, porém não diferem quanto ao rendimento do cacho. Quanto ao crescimento vegetativo, destaca-se o maior porte apresentado pelas novas cultivares, BRS Platina e BRS Princesa, podendo conferir às essas cultivares maior suscetibilidade ao tombamento, principalmente devido a frequência de ventos fortes na região. Em relação ao ciclo de produção as cultivares não diferem entre si. Quanto à qualidade pós-colheita dos frutos, as bananas \'BRS Platina\' apresentam um amadurecimento mais acelerado e, consequentemente, senescência dos frutos. Somente a cultivar BRS Platina apresenta correlação positiva entre variáveis vegetativas e produção. / São Paulo state stands out as the main producer of banana (Musa spp.). The commercial production is mostly concentrated at Vale do Ribeira region and São Paulo coast. However, at the 1990 decade Banana cultivation started spreading towards the Paulista plateau where farmers sought cropping diversification. Maintaining the use of traditional cultivars has been challenging due to their susceptibility to main diseases.This study aimed evaluating two recently breed tetraploids hybrids (AAAB), \'BRS Platina\' and \'BRS Princesa\' resistant to yellow Sigatoka (Mycosphaerella musicola, Leach), comparing it to the commonly used \'Prata-anã\' cultivar (AAB). Knowing that the adoption of a new hybrid does not take place by simply considering its resistance to diseases, the evaluation of vegetative parameters, bunch yield and its correlations, cycle duration and post-harvest quality of the fruits were necessary. The study was installed in Piracicaba-SP (latitude: 22 43\' 30\'\' S, longitude de 47 38\' 56\'\' W e altitude of 554 meters), with Cwa climate classification where most rain occurs during summer and the winter is dry and cold. The adopted experimental desing was randomized blocks, with three replicates and three plants per plot. The post-harvest evaluations took place in a complete randomized desing, with three replicates and plots composed of three bananas. The results were submitted to analysis of variance and Tukey test at the level of 5% of significance; Pearson correlation analysis and regression analysis. The most valuable results related, the \'BRS Platina\' and \'BRS Princesa\' demonstre higher resistance to yellow Sigatoka when compared to \'Prata-anã\' but there are no difference in yield as a result of the components of the bunch of each cultivar. The news cultivars have pseudostem taller than \'Prata-anã\'. In terms of post-harvest quality, bananas \'BRS Platina\' has early fruit maturation, when compared to the others, and consequently sooner beginning off fruit decease process. Only the \'BRS Platina\' has positive correlation between vegetative and production parameters.

The effects of edible chitosan coating on quality factors of pomegranate (Punica granatum) arils were investigated in the present research. For that purpose, pomegranate arils were treated with 0% (control) and 1% chitosan (extracted from shrimp shells and deacetylated (.75%)) solutions and stored at 4

Cucurbit yellow stunting disorder virus (CYSDV) is a relatively new virus affecting cantaloupe production in South Texas and worldwide. No resistant commercial cultivars are available. A cross of ‘Dulce’ (susceptible) x ‘TGR1551’ (resistant) was made and populations were developed for screening. Although no complete resistance was recovered, ‘TGR1551’ showed some tolerance and may be useful in breeding efforts. Sugar components such as sucrose, fructose, glucose, and total soluble solids are major factors in determining mature melon fruit sweetness, and Vitamin C is important for human health. A F2 population was developed from the melon cross ‘Dulce’ (high values) x ‘TGR1551’ (low values) and bulked segregant analysis was used to detect random amplified polymorphic DNA (RAPD) markers associated with quantitative trait loci (QTL) for each trait. Out of 500 primers, fifteen RAPD markers were found to be significantly associated with fruit quality QTL. These markers could be useful in a marker assisted selection program to transfer these genes into a low quality cultivar or breeding line to enhance fruit quality. Gummy stem blight (Didymella brioniae) affects melon production in South Texas as well as other melon production areas in the U.S. A cross between ‘TMS’ (susceptible) and PI 140471 (resistant) was made and a F2 population was screened with a strain of the disease from South Texas. F2 plants exhibited symptoms ranging from resistant to susceptible. PI 140471 may be useful in developing commercial varieties of melon resistant to the disease in Texas. Monosporascus root rot and vine decline (Monosporascus cannonballus) affects melon production in South Texas as well as other melon production areas in the US. A cross was made between ‘TGR1551’ (moderately resistant) and ‘Deltex’ (resistant) to develop a F2 population. Both parents and the F2 were planted in infested soil. Once symptoms appeared, plant roots were removed from the soil and rated. ‘TGR1551’ showed greater resistance than ‘Deltex’ and should be utilized in breeding to develop improved resistant cultivars.

Η εργασία αυτή πραγματοποιήθηκε με σκοπό τη μελέτη της επίδρασης διαφορετικών επιπέδων λίπανσης αζώτου, φωσφόρου και καλίου σε ποιοτικά χαρακτηριστικά των ξηρών καρπών της συκιάς (Ficus carica L.) της ποικιλίας «Καλαμών». Το πείραμα πραγματοποιήθηκε σε συκεώνα στο Νεοχώριο Μεσσήνης του νομού Μεσσηνίας το έτος 2009 και εφαρμόστηκαν στα δέντρα εννέα λιπαντικές επεμβάσεις, κάθε μια από τις οποίες αποτελούσε συνδυασμό διαφορετικών επιπέδων αζώτου (0,3 – 0,5 – 1 N kg ανά δέντρο), φωσφόρου (0 – 0,6 - 1,2 – 1,8 P2O5 kg ανά δέντρο) και καλίου (0 – 0,6 - 1,2 K2O kg ανά δέντρο), βάσει της καλλιεργητικής πρακτικής που εφαρμόζεται σε πολλές περιοχές του Ν. Μεσσηνίας. Οι επεμβάσεις που πραγματοποιήθηκαν ήταν οι ακόλουθες: Ν(0,3)-P(0)-K(0), N(0,3)-P(0,6)-K(0,6), N(0,3)-P(1,2)-K(0,6), N(0,3)-P(1,8)-K(0,6), N(0,5)-P(0,6)-K(0,6), N(1)-P(1,2)-K(0,6), N(1)-P(1,8)-K(0,6), N(0,3)-P(1,2)-K(1,2), N(1)-P(1,2)-K(1,2). Το πείραμα σχεδιάστηκε σύμφωνα με το πλήρως τυχαιοποιημένο σχέδιο και για κάθε επέμβαση χρησιμοποιήθηκαν τέσσερις επαναλήψεις (δέντρα). Η συγκομιδή πραγματοποιήθηκε σε δύο ημερομηνίες (20 και 29 Αυγούστου), όταν τα σύκα βρίσκονταν στο στάδιο της εμπορικής ωριμότητας ως ξηρό προϊόν. Μετά την ηλιοξήρανση των καρπών ακολούθησε διαλογή κατά την οποία απομακρύνθηκαν οι ελαττωματικοί καρποί (απόσυκα). Στα ξηρά σύκα που είναι κατάλληλα για εμπορία έγινε προσδιορισμός των εξής ποιοτικών χαρακτηριστικών: μέσο βάρος καρπού, διάμετρος του καρπού, περιεκτικότητα του καρπού σε υγρασία και ολικά διαλυτά στερεά, pH της πάστας του καρπού και τιτλοδοτούμενη οξύτητα της πάστας του καρπού. Από τα αποτελέσματα αυτής της μελέτης συμπεραίνεται ότι οι παραπάνω λιπαντικές επεμβάσεις δεν επηρεάζουν τα ποιοτικά χαρακτηριστικά των ξηρών σύκων που παράγονται στις συγκεκριμένες κλιματολογικές και εδαφολογικές συνθήκες. / The aim of the present study was to examine the effect of different nitrogen, phosphorus and potassium levels on some quality characteristics of dried fruits of fig tree (Ficus carica L. cv. Kalamon). The experiment was carried out at Neoxorio Messinis (Messinia, South Peloponesse, Greece) during 2009. Nine treatments which were the association of different levels of nitrogen (0,3 – 0,5 – 1 N kg per tree), phosphorus (0 – 0,6 - 1,2 – 1,8 P2O5 kg per tree), and potassium (0 – 0,6 - 1,2 K2O kg per tree), and were selected on the basis of the common cultural practices at Messinia, were applied. The following treatments: Ν(0,3)-P(0)-K(0), N(0,3)-P(0,6)-K(0,6), N(0,3)-P(1,2)-K(0,6), N(0,3)-P(1,8)-K(0,6), N(0,5)-P(0,6)-K(0,6), N(1)-P(1,2)-K(0,6), N(1)-P(1,8)-K(0,6), N(0,3)-P(1,2)-K(1,2), N(1)-P(1,2)-K(1,2) were applied according to the completely randomized experimental design. Each treatment was applied to four replicates (trees). Figs fruits were harvested at two different dates (20 and 29 August), when they were at the commercial maturity stage for consumption as dried figs. After sun drying, figs with defects were selected as cull figs (improper for commercial use). Marketable dried figs were used for measurement of quality characteristics such as: mean weight and mean diameter of the fruit, moisture and total soluble solids content of the fruit, pH and titratable acidity of fruit paste. From the results of this study, it is concluded that the above treatments with different amounts of nitrogen, phosphorus, and potassium do not affect the quality characteristics of dried figs produced at the soil-climatic conditions of this experiment.

Thesis (MSc Food Sc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Post-storage quality of the stone fruit, apricots and peaches, is the major factor determining their suitability for canning after cold storage in South Africa. Short harvesting periods and the limited capacity of the factory to process the large quantities of fruit within two days after delivery, necessitates cold storage until canning. Apricots develop internal breakdown, whereas peaches develop internal breakdown accompanied by loosening of the skin and adhesion of the flesh to the stone. The deterioration takes place within the fruit during a cold storage period of one to two weeks. The tendency of the fruit to develop internal defects can, to date, not be identified prior to storage and are only discovered after destoning during canning. Near infrared spectroscopy (NIRS) combined with chemometrics were investigated as a non-destructive method to predict post-storage quality in Bulida apricots and clingstone peach cultivars. Near infrared (NIR) spectra (645-1201 nm), measured on the intact fruit just after harvesting, were correlated with subjective quality evaluations performed on the cut and destoned fruit after cold storage. The cold storage periods for apricots were four weeks (2002 season) and three and two weeks for peach cultivars for the 2002 and 2003 seasons, respectively. Soft independent modelling by class analogy (SIMCA) and multivariate adaptive regression splines (MARS) were applied to the spectral and reference data to develop models for good and poor post-storage quality. The ability of these models to predict post-storage quality was evaluated in terms of recognition (sensitivity) and rejection (specificity) of the samples in independent validation sets. Total correct classification rates of 50.00% and 69.00% were obtained with Bulida apricots, using SIMCA and MARS, respectively. Classification results with apricots showed that MARS performed better than SIMCA and is thus recommended for this application. Total correct classification rates of 53.00% to 60.00% (SIMCA) and 57.65% to 65.12% (MARS) were obtained for data sets of combined peach cultivars within seasons and over both seasons. Additional aspects of fruit quality were investigated to identify possible indices of post-storage quality. Classification trees were used to find correlations between the post-storage quality and the fruit mass, diameter, firmness and soluble solids content (SSC). Among these, fruit diameter and firmness were the major indices of post-storage quality. Accurate predictions of firmness could not be achieved by near infrared spectroscopy (NlRS), making the combination of NIRS and classification trees not yet suitable for predicting post-storage quality. NIRS was further used to predict poststorage SSC within seasons in Bulida apricots and intact peach cultivars. This confirmed sufficient NIR light penetration into the intact fruit and also provided a further application of NIRS for ripeness evaluation in the canning industry. Validations on peach samples obtained correlation coefficients (r) of 0.77-0.85 and SEP-values of 1.35-1.60 °Brix using partial least squares (PLS) regression. MARS obtained r = 0.77-0.82 and SEP = 1.42-1.55 °Brix. Predictions of sse in apricots were less accurate, with r = 0.39-0.88, SEP = 1.24-2.21 °Brix (PLS) and r = 0.51-0.82, SEP = 1.54-2.19 °Brix (MARS). It is suggested that the accuracy of sse measurements, and the subsequent predictions, were affected by the cold storage periods as well as internal variation within the fruit. This study showed that a combination of NIRS and chemometrics can be used to predict post-storage quality in intact peaches and apricots. A small scale feasibility study showed that 4% (R117 720) (apricot industry) and 3% (R610 740) (peach industry) of production losses can be saved if this method is implemented in the South African canning industry. Although it was difficult to assign specific chemical components or quality attributes to the formulation of the storage potential models, important hidden information in the spectra could be revealed by chemometric classification methods. NIRS promises to be a useful and unique quality evaluation tool for the South African fruit canning industry. Several recommendations are made for the canning practices to reduce losses and for future research to improve the current prediction models. / AFRIKAANSE OPSOMMING: Die kwaliteit van die steenvrugte, appelkose en perskes, is die hoof bepalende faktor vir hul geskiktheid vir inmaakdoeleindes na koelopberging in Suid-Afrika. Die vrugte moet opgeberg word by lae temperature vir een tot twee weke, aangesien die oestydperk kort is en die kapasiteit van die fabriek te beperk is om die groot hoeveeheid vrugte dadelik in te maak. Tydens hierdie opbergingstydperk vind agteruitgang in die vrugte plaas. Dit word in appelkose gekenmerk deur interne verval en in perskes gekenmerk aan interne verval, tesame met enlos skil en die vaskleef van die vrugvlees aan die pit. Tot dusver, bestaan daar geen metode om hierdie tipe agteruitgang in vrugte voor opberging te identifiseer nie. Dit word eers na opberging opgemerk wanneer die vrugte ontpit word. Naby-infrarooi spektroskopie (NIRS), gekombineerd met chemometriese metodes is gebruik om opbergingspotensiaal in Bulida appelkose en taaipitperske kultivars te bepaal. enKorrelasie is gemaak tussen naby-infrarooi (NIR) spektra, gemeet op die heel vrugte voor opberging en subjektiewe evaluering van kwaliteit, geïdentifiseer op die gesnyde vrugte na opberging. Die opbergingstydperke vir perskes was vir drie en twee weke vir die 2002 en die 2003 seisoene, onderskeldeflk, terwyl die appelkose vir vier weke opgeberg is. Twee chemometriese metodes, "soft independent modelling by class analogy" (SIMCA) en "multivariate adaptive regression splines" (MARS) is gebruik om die spektra en ooreenstemmende subjektiewe data te kombineer en modelle is ontwikkel vir goeie en swak opbergingspotensiaal. Die vermoë van die modelle om die vrugkwaliteit na die opbergingstydperk te voorspel, is geêvalueer in terme van herkenning en verwerping van vrugtemonsters in onafhanklike toetsstelle. Totale korrekte klassifikasies van 50.00% and 69.00% is verkry vir Bulida appelkose, met SIMCA en MARS, onderskeidelik. Die klassifikasie resultate het gewys dat MARS beter gevaar het as SIMCA en word dus sterk aanbeveel vir hierdie toepassing. Totale korrekte klassifikasies van 53.00% tot 60.00% (SIMCA) and 57.65% tot 65.12% (MARS) is verkry vir gekombineerde perskekultivars tussen seisoene en oor seisoene. Verdere aspekte van vrugkwaliteit is geêvalueer om enmoontlike indeks van opbergingspotensiaal te verkry. Klassifikasiebome is gebruik om en korrelasie te vind tussen kwaliteit na opberging en vrugmassa, deursnee, fermheid en totale oplosbare vastestowwe (TOV). Diameter en fermheid het die meeste gekorreleer met die kwaliteit na opberging. Voorspellings van fermheid deur die gebruik van naby infrarooi spektroskopie (NIRS) was ~gter nie akkuraat nie. Dus word die kombinasie van klassifikasiebome en NIRS om opbergingspotensiaal te voorspel nie tans aanbeveel nie. NIRS is verder gebruik om TOV te voorspel binne seisoene in heel Bulida appelkose en perskekultivars. Dit is uitgevoer om voldoende NIR ligpenitrasie in die vrugte te bevestig en ook om 'n verdere toepassing van kwaliteitsbepaling (as indeks van soetheid en rypheid) vir die inmaakindustrie te verskaf. Validasies is op perskemonsters uitgevoer en korrelasiekoêffisiente (r) van 0.77-0.85 en voorspellingsfoute van 1.35-1.60 °Brix is verkry met "partial least squares" (PLS) regressie. MARS het r = 0.77-0.82 and voorspellingsfoute = 1.42-1.55 °Brix verkry. Die akkuraatheid van die TOV meetings en gevolglike voorspellings is waarskynlik beïnvloed deur interne variasie binne die vrugte sowel as die opbergings tydperke wat verloop het tussen metings. Hierdie studie wys dat NIRS en chemometriese metodes wel gebruik kan word om opbergingspotensiaal in heel perskes in appelkose te voorspel. 'n Kosteberekening het gewys dat besparings van 4% (R117 720) (appelkoos industrie) en 3% (R610 740) (perske industrie) moontlik is indien NIRS en MARS geïmplementeer word. Alhoewel dit moeilik was om spesifieke chemiese komponente en .sekere kwaliteitsaspekte aan die ontwikkeling van die modelle te koppel, is belangrike verborge informasie in die spectra uitgebring deur chemornetriese metodes. NIRS beloof om 'n bruikbare en unieke kwaliteitskontrole maatstaf te wees vir die Suid-Afrikaanse inmaakindustrie. Verskeie aanbevelings is gemaak vir die inmaakpraktyke om verliese te voorkom en ook vir toekomstige navorsing om die huidige klassifikasiemodelle te verbeter.

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Successful export of South African fresh fruit requires fruit of a high quality. Variable fruit quality within a consignment is detrimental to effective marketing of the product. The light microclimate under which the fruit develops is one of the factors that affect within-tree and between-tree variation in quality, maturity and yield. Light exposure effects on fruit quality at harvest and after commercial storage and ripening periods, as well as the physiological mechanisms of these responses to light exposure were studied. Increased exposure to light resulted in the development of typical sun leaf characteristics, with the associated increase in leaf nitrogen concentration and photosynthetic rates. Size and mass of 'Laetitia' plums and 'Cripps' Pink' apples increased with increasing exposure to light. Shade treatments were only started after the initial phase of cell / division was complete. Increased size of the fruit was likely due to the improved carbon balance of the exposed foliage and fruit from the end of cell division until harvest. The transpiration stream was higher in the more exposed foliage compared to the shaded parts of the canopy. This was supported by increased transpiration rates and decreased midday water potentials of exposed leaves. 'Songold' plums and 'Rosemarie' pears were also investigated in the first season, but results were not conclusive. Increased exposure to light was associated with advanced maturity of 'Laetitia' plums at harvest. Shaded fruit were able to attain a similar level of maturity as exposed fruit during storage and ripening periods. At harvest and after the storage and ripening periods, exposed fruit had a higher total soluble solid (TSS) content and therefore an improved eating quality. At harvest, blush colour of 'Laetitia' plums increased with increased exposure to irradiance. Blush colour continued to develop during storage and ripening, and after the ripening period it was evident that blush colour development was associated with a dosage effect i.e. exposure to a cumulative level of irradiance gives the fruit the potential to develop a certain amount of blush colour. Fruit exposed to more than 70% photosynthetic photon flux density (PPFD) were .able to develop to a similar level of blush colour, whereas, fruit exposed to less than 50% PPFD were not able to attain the same level of blush colour. Increased exposure to light did not result in advanced maturity of 'Cripps' Pink' apples at harvest, but it did lead to improved blush colour and increased TSS levels. Blush colour of 'Rosemarie' pears was also dependent on exposure to light from four weeks before harvest. Exposed 'Laetitia' plums had a greater whole fruit content of Mn and B, but concentration on a dry mass basis of P, K, and B decreased with increasing light. Exposed 'Cripps' Pink' apples had increased whole fruit content of P, K, Ca, Mg, Mn, Fe, Cu and B, but concentration on a dry mass basis of K and Na decreased with increasing light. Nutrient content is often associated with the incidence of internal disorders of fruit after storage and further investigation of this effect is necessary as internal disorders were virtually absent in this study. The termination of irrigation shortly before harvest in order to advance the maturity of all the fruit to a similar level, and the subsequent strip harvest of the fruit on a single harvest date, is a practice commonly used by South African plum producers to reduce cost and ostensibly to improve fruit quality. The effect of this practice on 'Songold' plum quality at harvest, after storage and after ripening was also studied. Drip-irrigated plums and plums subjected to soil drying had a better eating quality and were more marketable than micro-irrigated and non-droughted fruit. Following commercial storage and ripening periods these fruit were firmer, had a higher TSS content and were of a similar size and mass to micro-irrigated and non-droughted fruit. The extended harvesting period, in contrast to a strip harvest, allowed the fruit that were smaller and less mature at the beginning of the period to attain a greater size and advanced maturity toward the end of the harvesting period. / AFRIKAANSE OPSOMMING: Suksesvolle uitvoer van Suid-Afrikaanse vars vrugte vereis volgehoue hoë gehalte. Wisselvallige vruggehalte binne 'n besending is nadelig vir die effektiewe bemarking van die produk. Die lig mikroklimaat waaronder die vrug ontwikkel is een van die faktore wat variasie in gehalte, rypheidsstadium en opbrengs binne die boom en tussen bome beïnvloed. Die effek van verhoogde ligblootstelling op vruggehalte by oes, na kommersiële opberging en na die rypwordingsperiode, sowel as die fisiologiese meganismes van die reaksie van verhoogde ligblootstelling is bestudeer. Verhoogde blootstelling aan lig lei tot die ontwikkeling van tipiese son-blaar karaktertrekke, met die gepaardgaande verhoging in blaar stikstof konsentrasie en fotosintetiese tempo. Grote en massa van 'Laetitia' pruime en 'Cripps' Pink' appels het toegeneem met verhoogde blootstelling aan lig. Skadu behandelings is eers begin na die einde van die periode van selverdeling. Toenemende grootte van die vrugte is as gevolg van die verbeterde koolstofbalans van die blootgestelde blare en vrugte vanaffase II van vruggroei tot oestyd. Die transpirasie stroom is geallokeer na die blootgestelde blare. Dit word ondersteun deur die verhoogde transpirasie tempo en verminderde middag waterpotensiaal van die blootgestelde blare. 'Songold' pruime en 'Rosemarie' pere is ook bestudeer, maar die uitslae is nie so oortuigend nie. Toenemende blootstelling aan lig is geassosieer met gevorderde rypheid van 'Laetitia' by oes. Dit was moontlik vir skadu vrugte om dieselfde rypheidsvlak as blootgestelde vrugte te bereik, tydens die opberging en rypwording periodes. Teen oestyd en na opberging en rypwording, het blootgestelde vrugte 'n hoër suiker inhoud gehad en dus 'n hoër eetgehalte. Teen oestyd, het die bioskleur van die pruime toegeneem met toenemende blootstelling aan lig. Ontwikkeling van bloskleur het aangehou gedurende opberging en rypwording, en na die die rypwordings periode was dit duidelik dat bioskleur ontwikkeling met 'n dosis-effek geassosieer word, m.a.w. blootstelling aan 'n sekere opgestapelde vlak van lig gee die vrug die potensiaal om 'n sekere hoeveelheid bioskleur te ontwikkel. Vrugte wat meer as 70% ligblootstelling gekry het, het dieselfde bioskleur ontwikkel, maar vrugte wat minder as 50% ligblootstelling gekry het, het minder bloskleur ontwikkel. Toenemende blootstelling aan lig het nie gelei tot gevorderde rypheid van 'Cripps' Pink' appels teen oestyd nie, maar dit het wel gelei tot verbeterde bioskleur en verhoogde suiker inhoud. Bloskleur van 'Rosemarie' pere is afhanklik van blootstelling aan lig kort voor oestyd. Blootgestelde 'Laetitia' pruime het 'n verhoogde vrug inhoud van Mn en B met verhoogde ligblootstelling gehad, maar die konsentrasie van P, K en B op 'n droë massa basis het afgeneem met verhoogde ligblootstelling. Blootgestelde 'Cripps' Pink' appels het 'n verhoogde vrug inhoud van P, K, Ca, Mg, Mn, Fe, Cu en B met verhoogde ligblootstelling gehad, maar die konsentrasie van K en Na op 'n droë massa basis het afgeneem met verhoogde ligblootstelling. Voedingstof inhoud is geassosieer met die voorkoms van interne probleme in vrugte na opberging en verdere navorsing oor hierdie effek is nodig. Die terminering van besproeiing kort voor oestyd met die doelom die rypheid van al die vrugte op dieselfde vlak te kry sowel as die gepaardgaande oes van al die vrugte op een dag, is 'n algemene praktyke wat gebruik word deur Suid-Afrikaanse pruim produsente om kostes te beperk en oënskynlik, om vruggehalte te verbeter. Die effek van hierdie praktyke op 'Songold' pruim gehalte teen oestyd, na opberging en na rypwording is ook bestudeer. Drup-besproeide pruime en pruime wat blootgestel is aan grond uitdroging het 'n beter eetgehalte en is meer bemarkbaar as mikro-besproeide en nie-droogte geïnduseerde vrugte. Na kommersiële opberging en rypwording periodes het hierdie vrugte 'n hoër fermheid en suiker inhoud gehad, en 'n gelyksoortige grootte en massa as mikrobesproeide en nie-droogte geïnduseerde vrugte. Die verlengde oesperiode het die kleiner en minder ryp vrugte aan die begin van die periode 'n kans gegee om toe te neem in grootte en 'n gevorderde vlak van rypheid te bereik aan die einde van die oesperiode.

Thesis (MScAgric)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Fruit size and the integrity of the rind are key components that determine the value of a citrus fruit. The application of 2,4-dichlorophenoxy acetic acid (2,4-D) to reduce splitting, a physiological disorder which entails cracking of the rind as well as to increase fruit size was conducted on three different split-susceptible mandarin and two split-susceptible orange cultivars. Treatments were applied directly after the physiological fruit drop period, as well as in January and February at 10 mg·L-1, alone or in combination with calcium (Ca), potassium (K) or gibberellic acid (GA3). Application of 2,4-D directly after physiological fruit drop, either alone or in a tank-mix with K, consistently reduced the number of split mandarin fruit, with later applications in January and February generally being ineffective. Post physiological fruit drop application of 10 mg·L-1 2,4-D significantly increased growth rate (mm.day-1) of all the mandarin cultivars, resulting in increased fruit size. Differences in sensitivity of cultivars to 2,4-D were evident, with the January application reducing the splitting in ‘Midknight’ Valencia. However, all the 2,4-D treatments reduced the fruit growth rate of the orange cultivars. The 2,4-D treatments, in terms of splitting, increased rind thickness, -strength and -coarseness of ‘Marisol’ Clementine, throughout fruit development. In addition fruit diameter and –length increased to such an extent that the fruit shape was altered (reduced d/l-ratio), reducing the potential of the rind to crack and the fruit to split, however rind coarseness of treated fruit was also increased. There were no major negative side effects on internal and external fruit quality, except for a possible reduction in juice content (%). Therefore, 10 mg·L-1 2,4-D can be applied directly after physiological fruit drop on ‘Marisol’ Clementine and ‘Mor’ mandarin to reduce fruit splitting. / AFRIKAANSE OPSOMMING: Vruggrootte asook die integriteit van die skil is belangrike aspekte in die bepaling van ʼn sitrusvrug se waarde. Die toediening van 2,4-dichlorofenoksie asynsuur (2,4-D) om vrugsplit, 'n fisiologiese defek wat tot die kraak van die sitrusskil lei, te verminder is getoets op drie mandaryn- en twee lemoenkultivars. Hiermee saam is die potensiaal van 2,4-D om vruggrootte te verbeter ook geëvalueer. Die 2,4-D behandelings is direk na die fisiologiese vrugval periode toegedien, asook in Januarie en Februarie, teen 10 mg·L-1, alleen of in kombinasie met kalsium (Ca), kalium (K) of gibberelliensuur (GS3). Al die mandarynkultivars het ʼn vermindering in die totale aantal gesplete vrugte getoon indien die 2,4-D (enkel of in kombinasie met K) toegedien was direk na fisiologiese vrugval. Suksesvolle behandelings het ook 'n toename in vruggrootte tot gevolg gehad. Toediening van behandelings in Januarie en Februarie was oor die algemeen oneffektief. Verskille in kultivar sensitiwiteit teenoor 2,4-D is gevind, met vrugsplit in ‘Midknight’ Valencia wat verminder was deur die Januarie toediening van 2,4-D. Al die 2,4-D behandelings het vruggrootte van die lemoenkultivars verlaag. Daar is bevind dat die 10 mg.L-1 2,4-D, enkel of in kombinasie met K, ‘n toename in beide skildikte en –sterkte van ‘Marisol’ Clementine teweeg bring asook ʼn growwer skil. Behandelings met 2,4-D het vrugdeursnee en –lengte laat toeneem, wat ʼn verandering in vrugvorm tot gevolg gehad het, tot so ʼn mate dat vrugte minder geneig was om gesplete te wees. Behalwe vir ʼn moontlike verlaging in die sapinhoud (%) van vrugte, was daar geen noemenswaardige negatiewe effekte op interne en eksterne vrugkwaliteit nie. Die toediening van 10 mg.L-1 2,4-D direk na fisiologiese vrugval kan dus aanbeveel word op mandaryn kultivars wat geneig is tot vrugsplit. / The Citrus Academy