Publications - Merete Halkjær Olesen

Importance of seed quality for the fresh cut chain

Deleuran, L. C., Olesen, M. H., Shetty, N., Gislum, R., Boelt, B. — Thu, 30 Aug 2018 08:43:05 +0200

Seed is the most fundamental input in vegetable production on which the effectiveness of other inputs and outputs depends. If the seed is of poor quality, the use of other inputs is less successful and will occasionally be irrelevant. A definition of seed quality will depend upon the use for which the seed is intended. Viability, vigor, uniformity, purity and health of the seeds are quality parameters important for all production systems. The ideal situation for both fresh produce and fresh cut would be seeds that germinate uniformly at a high percentage and subsequently grow relatively fast to the desired size, thus, resulting in leaves of improved quality. It is likely that such leaves will be more able to withstand the rigorous processing that includes harvest, transportation, washing, sanitization, de-watering and packaging. This ideal situation would both be determined by the mentioned properties of the seeds and to a large extend the cultivar of the seeds. The quality of a vegetable product is defined by the interaction of these factors, including environmental factors as well as by management and technology. Novel, fast and non-destructive technologies for seed testing allow for new sorting possibilities of a seed lot. At present, new initiatives using multispectral imaging and single seed NIR spectroscopy is being developed at AU for description of seed lots. Preliminary results on investigations of pak choi seeds are presented.

Effect of Verticillium dahliae soil inoculum levels on spinach seed infection

Sapkota, R., Olesen, M. H., Deleuran, L. C., Boelt, B., Nicolaisen, M. — Fri, 01 Jan 2016 08:43:05 +0100

Verticillium dahliae is a soilborne pathogen and a threat to spinach seed production. The aim of this study was to understand the relation between V. dahliae soil inoculum and infection in harvested seed. Quantitative polymerase chain reaction was used for quantification of the pathogen. Semifield experiments in which spinach was grown in soils with different inoculum levels enabled us to determine a threshold level for V. dahliae DNA of 0.003 ng/g of soil for seed infection to occur. Soils from production fields were sampled in 2013 and 2014 during and before planting, as well as the harvested seed. Seed from plants grown in infested soils were infected with V. dahliae in samples from both the semifield and open-field experiments. Lower levels of pathogen were found in seed from spinach grown in soils with a scattered distribution of V. dahliae (one or two positive of three soil subsamples) than in soils with a uniform distribution of the pathogen (three of three positive soil subsamples). Our results showed that infection of V. dahliae in harvested seed strongly depended on the presence of pathogen inoculum in the soil.

The Use of Image-Spectroscopy Technology as a Diagnostic Method for Seed Health Testing and Variety Identification

Vrešak, M., Halkjaer Olesen, M., Gislum, R., Bavec, F., Ravn Jørgensen, J. — Thu, 24 Mar 2016 08:43:05 +0100

Application of rapid and time-efficient health diagnostic and identification technology in the seed industry chain could accelerate required analysis, characteristic description and also ultimately availability of new desired varieties. The aim of the study was to evaluate the potential of multispectral imaging and single kernel near-infrared spectroscopy (SKNIR) for determination of seed health and variety separation of winter wheat (Triticum aestivum L.) and winter triticale (Triticosecale Wittm. & Camus). The analysis, carried out in autumn 2013 at AU-Flakkebjerg, Denmark, included nine winter triticale varieties and 27 wheat varieties provided by the Faculty of Agriculture and Life Sciences Maribor, Slovenia. Fusarium sp. and black point disease-infected parts of the seed surface could successfully be distinguished from uninfected parts with use of a multispectral imaging device (405-970 nm wavelengths). SKNIR was applied in this research to differentiate all 36 involved varieties based on spectral differences due to variation in the chemical composition. The study produced an interesting result of successful distinguishing between the infected and uninfected parts of the seed surface. Furthermore, the study was able to distinguish between varieties. Together these components could be used in further studies for the development of a sorting model by combining data from multispectral imaging and SKNIR for identifying disease(s) and varieties.

The use of image-spectroscopy technology as a diagnostic method for seed health tests and variety identification

Vrešak, M., Olesen, M. H., Gislum, R., Bavec, F., Jørgensen, J. R. — Tue, 24 Nov 2015 08:43:05 +0100

Seed set and seed development in perennial ryegrass and the effects on seed quality

Boelt, B., Olesen, M. H., Abel, S., Gislum, R. — Sun, 21 Jun 2015 08:43:05 +0200

Visnesyge har mange værter på vejen til spinat

Olesen, M. H. — Wed, 01 Jul 2015 08:43:05 +0200

Viability Prediction of Ricinus cummunis L. Seeds Using Multispectral Imaging

Olesen, M. H., Nikneshan, P., Shrestha, S., et al. — Thu, 01 Jan 2015 08:43:05 +0100

The purpose of this study was to highlight the use of multispectral imaging in seed quality testing of castor seeds. Visually, 120 seeds were divided into three classes: yellow, grey and black seeds. Thereafter, images at 19 different wavelengths ranging from 375–970 nm were captured of all the seeds. Mean intensity for each single seed was extracted from the images, and a significant difference between the three colour classes was observed, with the best separation in the near-infrared wavelengths. A specified feature (RegionMSI mean) based on normalized canonical discriminant analysis, were employed and viable seeds were distinguished from dead seeds with 92% accuracy. The same model was tested on a validation set of seeds. These seeds were divided into two groups depending on germination ability, 241 were predicted as viable and expected to germinate and 59 were predicted as dead or non-germinated seeds. This validation of the model resulted in 96% correct classification of the seeds. The results illustrate how multispectral imaging technology can be employed for prediction of viable castor seeds, based on seed coat colour.

Use of Multispectral Imaging in Varietal Identification of Tomato

Shrestha, S., Deleuran, L. C., Olesen, M. H., Gislum, R. — Thu, 01 Jan 2015 08:43:05 +0100

Abstract: Multispectral imaging is an emerging non-destructive technology. In this work its potential for varietal discrimination and identification of tomato cultivars of Nepal was investigated. Two sample sets were used for the study, one with two parents and their crosses and other with eleven cultivars to study parents and offspring relationship and varietal identification respectively. Normalized canonical discriminant analysis (nCDA) and principal component analysis (PCA) were used to analyze and compare the results for parents and offspring study. Both the results showed clear discrimination of parents and offspring. nCDA was also used for pairwise discrimination of the eleven cultivars, which correctly discriminated upto 100% and only few pairs below 85%. Partial least square discriminant analysis (PLS-DA) was further used to classify all the cultivars. The model displayed an overall classification accuracy of 82%, which was further improved to 96% and 86% with stepwise PLS-DA models on high (seven) and poor (four) sensitivity cultivars, respectively. The stepwise PLS-DA models had satisfactory classification errors for cross-validation and prediction 7% and 7%, respectively. The results obtained provide an opportunity of using multispectral imaging technology as a primary tool in a scientific community for identification/discrimination of plant varieties in regard to genetic purity and plant variety protection/registration.

Preventing an increase in Verticillium wilt incidence in spinach seed production

Olesen, M. H., Deleuran, L. C., Gislum, R., Boelt, B. — Mon, 01 Dec 2014 08:43:05 +0100

A semifield assay was conducted from 2009 to 2011 to distinguish between different preventive methods of reducing Verticillium spp. in spinach seed production. The seed treatments for controlling seed infection levels included Thiram, Signum, Trichoderma harzianum, Gliocladium roseum and Natural II, and these were tested in naturally infested and uninfested soil. Even though seed treatment by Thiram and Signum in all cases reduced the incidence of Verticillium spp. on the harvested seed, the soil type had a large influence on the subsequent disease pressure as a significant effect of soil was seen in 2010 and 2011 and a non-significant effect of seed treatment on Verticillium spp. was observed in all experimental years. As no interaction between soil and seed treatment was observed, the seed treatment had no effect on the disease pressure on the seeds subsequently harvested from the infested soil.

Spray mass balance in pesticide application

Jensen, P. K., Olesen, M. H. — Wed, 01 Jan 2014 08:43:05 +0100

When pesticides are applied to arable and orchard crops, the pesticide will be deposited in the field on either the crop or the ground, or the pesticide can be transported outside the treated area as spray drift. Spray drift is divided into two fractions, sedimenting spray drift and airborne spray drift. Deposits on the crop and the ground as well as sedimenting spray drift are measured using documented and validated methods. Airborne drift is more difficult to quantify, and the methods need to be improved. A review of studies reporting crop and soil deposits in the treated area was used to calculate spray mass balances. Taking into account standard values of sedimenting spray drift for the application method applied, the airborne spray drift fraction was calculated as the difference between the applied dose and the sum of the recovered doses on crop and soil and sedimenting spray drift. This resulted in high values for airborne spray drift with the lowest values recorded in studies on application in field crops using boom sprayers and in vineyards using tunnel sprayers. In studies using traditional orchard sprayers in vineyards and tree fruit, large fractions of the spray were not found in the recovery analysis.

Collection and evaluation of relevant information on crop interception

Olesen, M. H., Jensen, P. K. — Tue, 01 Jan 2013 08:43:05 +0100

Forekomst af visnesyge og andre svampesygdomme i spinat til frø med fokus på infektion af henholdsvis jord og frø

Olesen, M. H., Deleuran, L. C. — Sun, 01 Jan 2012 08:43:05 +0100

I mange havefrøafgrøder kan det være svært at producere frø helt fri for sygdomme samt at finde sygdomsfrie jorde til videre frøproduktion. Bedre kendskab til hvilke sygdomme, der er i både frø og jord kan derfor identificere strategier til en bedre fremtidig frøproduktion af spinat. I første omgang er det
vigtigt, at der arbejdes på at reducere sygdomstrykket i både frø og jord. Identifikation af sygdomsproblemer under produktionen i marken giver mulighed for bekæmpelse af sygdommen i det omfang, der er godkendte midler, som virker. Sammenhæng mellem infektion på planterne og på frøet efter høst er
et område, hvor der er meget lidt viden. Ved et bedre kendskab til smittetrykket kan man undgå at så inficeret udsæd i jomfruelig jord (”ikke smittet jord”) og omvendt være opmærksom på ikke at så uinficeret udsæd i inficerede jorde. Undersøgelser fra Holland og USA har vist, at forekomsten af V. dahliae
i frøpartier er forøget de senere år. I Holland blev der i 1973 påvist V. dahliae i 20 ud af 34 testede frøpartier. I amerikanske undersøgelser blev der i 2003 påvist V. dahliae i 57 ud af 62 partier. Denne høje infektionsgrad bekræfter behovet for øget kontrol af frøpartier. Ved AU Flakkebjerg er der i perioden 2008-2010 lavet en række forsøg for at evaluere potentielle fremgangsmåder,
der kan reducere infektionen af visnesyge og andre svampesygdomme i spinatfrø. Dette ved at så spinatfrø i uinficeret jord og jord naturligt inficeret med henholdsvis F. oxysporium f.sp. spinaciae og V. dahliae. I samme forsøg undersøges forskellige frø og jordbehandlinger, som potentielle mulige
metoder til reduktion af smittetrykket i jorden og på frøet. I 2009 blev der observeret en reduktion i infektionsniveauet af V. dahliae på det høstede frø, når de anvendte stamfrø var behandlet med Thiram.

Bekæmpelse af svampesygdomme i spinat

Paaske, K., Olesen, M. H., Deleuran, L. C., Feidenhans'l, B. . — Sun, 01 Jan 2012 08:43:05 +0100

Svampesygdomme kan være et stort problem i spinatfrøavlen. De mest alvorlige sygdomme er Cladosporium-bladplet, Stemphylium-bladplet og spinatskimmel. I spinat til frø kan sygdommene betyde både tab af frøudbytte og kvalitetsforringelser i det høstede frø. Et inficeret frøparti resulterer efterfølgende
i planter med reduceret vækst, grundet bladinfektion. I perioden 2005-2008 er der gennemført 8 Landsforsøg med forskellige strategier til bekæmpelse af
svampesygdomme i spinat. Ligeledes har der ved AU Flakkebjerg været forsøg med sprøjtninger med Signum, Opera og Cantus i perioden 2006-2008. Resultaterne af forsøgene viser pæne merudbytter for bekæmpelse af svampesygdomme i spinatfrøproduktionen. I forsøgene fra AU ses endvidere, at svampebekæmpelsen giver en reduktion af forekomsten af Stemphyllium botryosum og Cladosporium spp. på det høstede spinatfrø.

Spinach seed quality - potential for combining seed size grading and chlorophyll flourescence sorting

Deleuran, L. C., Olesen, M. H., Boelt, B. — Tue, 01 Jan 2013 08:43:05 +0100

Spinach (Spinacia oleracea L.) seed quality is important for subsequent establishment of baby leaf and other spinach products. The indeterminate flowering pattern in spinach produces seeds of different sizes, and consequently a non-uniform seed lot. Sorting seeds based on novel sorting methods might therefore improve the establishment of spinach for producers. Spinach seeds were harvested at five different times (H1, H2, H3, H4 and H5) starting 3 weeks before estimated optimum harvest time. The harvested seeds were sorted according to chlorophyll fluorescence (CF) and seed size. Two harvest times 6 d apart were selected for further studies of seed development and germination counts. Analysis of mean germination time (MGT) of four germination counts (3, 7, 14 and 21 d) showed that smaller seed sizes ( < 3.25 mm) have lower MGT than seeds of larger sizes (>3.25 mm). A larger proportion of 2.5–3.25 mm size seeds had germinated on day 3 than both their larger and smaller counterparts at the later time of harvest (H4). Seeds with a diameter below 2.5 mm displayed the lowest MGT. Commercially, the use of chlorophyll fluorescence (CF)-sorted seeds, in combination with seed size sorting, may provide a useful tool for enhancing seed quality. Here our results demonstrate that a greater number of seeds with a low CF level had germinated on day 3 compared to the seeds with high CF levels. It is of relevance to develop a technology that could identify seeds that are sufficiently developed to germinate and successfully establish in the field regardless of seed size.

Improvement and evaluation of vegerable seed quality by the use of non-destructive technologies

Olesen, M. H. — Sun, 01 Jan 2012 08:43:05 +0100

Samspillet mellem frø, svampe og brugen af ikke destruktive teknologier til bestemmelse af grønsags frø kvalitet er undersøgt og beskrevet i denne ph.d.-afhandling. I kapitel 2 beskrives frøets morfologi samt vigtige biokemiske og fysiologiske aspekter, som har indflydelse på frøets kvalitet. På baggrund af dette teoriafsnit illustreres således kompleksiteten i at kunne kontrollere frøets spireevne og sundhed. Det forventes, at brugen af ikke destruktive teknologier sammen med bedre kontrol af svampeinfektioner i jorden, på sigt vil forbedre
kvaliteten af de høstede frø, og dermed forbedre kvaliteten af grønsagsproduktionen. I kapitel 3 gives en oversigt over de metoder, der anvendes i dag, og en beskrivelse af nye potentielle teknologier, som vil være af stor værdi i fremtidens frøforskning og kvalitetskontrol.
Eksperimentelt er forsøg udført med spinat som modelafgrøde. Spinat frø blev valgt, fordi spinat er den vigtigste afgrøde i dansk grønsagsfrø produktion. Resultaterne fra det eksperimentelle arbejde er beskrevet i tre artikler der omhandler brugen af enkelt kerne NIR spektroskopi (I), multispektral billede analyse (V) samt brugen af Verticillium spp. inficeret jord til produktion af spinat frø (III). Endvidere er der to konference artikler, som beskriver det indledende forsøgsarbejde og resultater ved brugen af multispektral billede analyse til
forudsigelse af spireevne (II) og bestemmelse af frø sundhed (IV).
Resultater fra enkelt kerne NIR målingerne bekræftede, at forudsigelse af spireevne er muligt på frø med og uden pericarp. Data er baseret på diffuse reflektants målinger af det biokemiske indhold i pericarp, testa, perisperm, micropylar endosperm og embryoet. De nævnte strukturer formodes alle at påvirke frøets evne til spiring. For at øge antallet af ikke-spirende frø, blev halvdelen af frø prøverne udsat for en accelereret ældning (i varmeskab ved 41°C i 72 timer). Ved brug af NIR målingerne var det således også muligt at detektere nogle af de biokemiske ændringer, der sker ved ældning af frøet. Ved evaluering af forskellen imellem de korrigerede spektre for de forskellige frø prøver (ikke spirende, spirende, ældet, ikke ældet) kunne der ses en forskel i de bånd, som afspejler CH2, CH3 og HC=CH strukturer. Denne observation hænger godt sammen med resultater af tidligere biokemiske analyser, hvor det er vist, at der sker en nedbrydning af lipid forbindelser ved initiering af spiringsprocessen. Under accelereret ældning sker der en lipid-peroxidation, som fører til en ødelæggelse af 14 cellemembraner, og dermed medfører en nedsat spireevne af frøene. På baggrund af NIR målingerne var det muligt at lave en klassifikationsmodel der kunne bruges til at forudsige frøenes spireevne med 89.5 % til 98.3 % nøjagtighed afhængig af om frøene var med eller
uden pericarp, ældet eller om frøene blev spiret ved 15 °C eller 25 °C.
Brugen af multispektral billedanalyse blev testet med det formål at undersøge om lys ved 19 forskellige bølgelængder (fra 395 nm-970 nm) kan benyttes til bestemmelse af frø sundhed og spireevne. Data fra billeder er baseret på overfladeegenskaber af frøene og i det indledende forsøg præsenteret i artikel II, var det muligt ved brug af NIR bølgelængder at forudsige spireevnen af 24 ud af 25 frø.
Behovet for bedre kontrol af infektion af både frø og jord i spinat frø produktion blev illustreret i et potteforsøg med Verticillium spp. inficeret jord (Papir III). Her blev det vist, at frø høstet fra planter dyrket i inficeret jord, medførte inficeret frø alle tre år forsøget blev udført. For at undgå en inficering af nye marker må det derfor antages at være nødvendigt at analysere alle frø-partier inden såning. Endvidere blev der i forsøget testet forskellige kemiske og biologiske behandlinger, men ingen af behandlingerne førte til reduktion af Verticillium
spp. på det høstede frø.
Mulighederne i at bruge multispektral billede analyse, som en hurtig og ikke-destruktiv analysemetode, til bestemmelse af infektions niveauer på de høstede frø er illustreret i artikel IV og V. Til opbygning af en klassifikationsmodel blev analyserne først lavet på billeder af kunstigt smittede frø og efterfølgende blev modellen testet på billeder af naturligt inficerede
frø. Gennemsnitlige pixelværdier fra et udvalgt område på overfladen af frøene blev brugt til adskillelse af ikke-inficerede frø fra frø smittet med Verticillium spp. Fusarium spp. Stemphylium botryosum, Cladosporium spp. eller Alternaria spp. Frø inficeret med Fusarium spp. kunne adskilles fra de øvrige svampe arter, men det var ikke muligt at adskille Stemphylium botryosum, Cladosporium spp. og Verticillium spp. fra hinanden. Analyserne viste, at den bedste adskillelse mellem inficerede og ikke-inficerede frø opnås ved brug af både
VIS og NIR bølgelængder

Single seed NIR as a fast method to predict germination ability in Pak Choi

Gislum, R., Deleuran, L. C., Olesen, M. H., Tveden-Nyborg, S., Boelt, B. — Sun, 01 Jan 2012 08:43:05 +0100

Single seed NIR has further been tested to determine the applicability for prediction of seed viability in radish (Raphanus sativus L.) seeds and spinach (Spinacia oleracea L.) seeds. The studies show the possibility of using NIR spectroscopy in a seed separating process in the future, provided that appropriate sorting devices are developed. This article discusses the possibility of using this method to predict germination ability in Pak Choi.

Optimal sample size for predicting viability of cabbage and radish seeds based on near infrared spectra of single seeds

Shetty, N., Min, T., Gislum, R., Olesen, M. H., Boelt, B. — Sat, 01 Jan 2011 08:43:05 +0100

The effects of the number of seeds in a training sample set on the ability to predict the viability of cabbage or radish seeds are presented and discussed. The supervised classification method extended canonical variates analysis (ECVA) was used to develop a classification model. Calibration sub-sets of different sizes were chosen randomly with several iterations and using the spectral-based sample selection algorithms DUPLEX and CADEX. An independent test set was used to validate the developed classification models. The results showed that 200 seeds were optimal in a calibration set for both cabbage and radish data. The misclassification rates at optimal sample size were 8%, 6% and 7% for cabbage and 3%, 3% and 2% for radish respectively for random method (averaged for 10 iterations), DUPLEX and CADEX algorithms. This was similar to the misclassification rate of 6% and 2% for cabbage and radish obtained using all 600 seeds in the calibration set. Thus, the number of seeds in the calibration set can be reduced by up to 67% without significant loss of classification accuracy, which will effectively enhance the cost-effectiveness of NIR spectral analysis. Wavelength regions important for the discrimination between viable and non-viable seeds were identified using interval ECVA (iECVA) models, ECVA weight plots and the mean difference spectrum for viable and no- viable seeds.

Use of partial least squares discriminant analysis on visible-near infrared multispectral image data to examine germination ability and germ length in spinach seeds

Shetty, N., Olesen, M. H., Gislum, R., Deleuran, L. C., Boelt, B. — Sun, 01 Jan 2012 08:43:05 +0100

Because of the difficulties in obtaining homogenous germination of spinach seeds for baby leaf production, the possibility of using partial least squares discriminant analysis (PLS-DA) on features extracted from multispectral images of spinach seeds was investigated. The objective has been to discriminate between different seed sizes, as well as to predict germination ability and germ length. Images of 300 seeds including small, medium, and large seeds were taken, and the seeds were examined for germination ability and germ length. PLS-DA loadings plots were used to reduce the multidimensional image features to a few important features. The PLS-DA prediction resulted in an independent test set not only providing discrimination of seed size but also demonstrating how germination ability and germ length vary according to seed size. The result indicated that larger seeds had both a significantly higher germination potential and germ length compared with smaller seeds. The variable importance for projection method showed that the near infrared (NIR) wavelength region is important for germination predictability. However, the PLS-DA model did not improve when only the NIR region was used.

Classification of viable and non-viable spinach (Spinacia oleracea L.) seeds by single seed near infrared spectroscopy and extended canonical variates analysis

Olesen, M. H., Shetty, N., Gislum, R., Boelt, B. — Mon, 27 Jun 2011 08:43:05 +0200

Near-infrared (NIR) reflectance spectroscopy is a common non-destructive method for predicting seed quality parameters, such as moisture, oil, carbohydrates and protein content. Furthermore, variations in absorbance between germinating and non-germinating seeds have been shown in single seed studies. Spinach (Spinacia oleracea L.) is the major crop in vegetable seed production in Denmark and two seed lots with viability percentages of 90% and 97% were chosen for examination by single seed NIR spectroscopy. Lipids play a major role in both ageing and germination. During accelerated ageing, lipid peroxidation leads to deterioration of cell membranes and contributes in that way to reducing seed viability of the seed sample. These biochemical changes may be the reason for a clear grouping between aged and non-aged seeds when performing the extended canonical variates analysis (ECVA). Assigning the difference of scatter corrected absorbance spectra from aged and non-aged seeds also lead to CH2, CH3 and HC=CH structures, which are some of the functional groups in lipids. In the ECVA plot, there was a clear difference between seeds with and without a pericarp. Evaluating the spectra, the pattern of peaks was almost similar, but the intensity was different in the absorption band at 1350 nm. The number of misclassified seeds ranged from 1.7% to 10.5% and it was lowest in seeds with a pericarp. This indicates the influence of the pericarp during germination, which is in accordance with earlier studies of spinach seeds. Single seed NIR and ECVA classification are potential methods for the prediction of seed viability.

Multispectral imaging as a potential tool for seed health testing of spinach (Spinacia oleracea L.)

Olesen, M. H., Carstensen, J. M., Boelt, B. — Fri, 01 Apr 2011 08:43:05 +0200

Seed health tests are time consuming and require substantial training for characterization of pathogenic fungi on seed. A new approach to use a multispectral vision system for identifying surface properties of different fungal infections has been tested in spinach (Spinacia oleracea L.) at Aarhus University. Our study demonstrates that multispectral imaging with wavelengths ranging from 395-970 nm can be used to distinguish between uninfected spinach seeds and seeds infected with Verticillium spp., Fusarium spp., Stemphylium botryosum, Cladosporium spp. and Alternaria alternata. Analytical separation based on mean pixel intensity, Canonical Discriminant Analysis (CDA) and classification by Jeffries-Matusita (JM) distance illustrates that a combination of Near Infrared spectra (NIR) and Visual spectra (VIS) is able to identify uninfected seeds from infected seeds ranging from 80-100%. Classification using only NIR gave a separation of 26-88% between uninfected and Fusarium spp. infected seeds. Alternaria alternata and Fusarium spp. could be distinguished from each other and from Cladosporium spp., Verticillium spp. and Stemphylium spp. Separation of Cladosporium spp., Verticillium spp. and Stemphylium spp. needs further development before practical application.

Importance of Seed Quality for the Fresh-cut Chain

Deleuran, L. C., Olesen, M. H., Shetty, N., Gislum, R., Boelt, B. — Sat, 01 Jan 2011 08:43:05 +0100

Seed is the most fundamental input in vegetable production on, which the
effectiveness of other inputs and outputs depends. If the seed is of poor
quality, the use of other inputs is less successful and will occasionally be
irrelevant. A definition of seed quality will depend upon the use for, which
the seed is intended. Viability, vigor, uniformity, purity and health of the
seeds are quality parameters important for all production systems. The ideal
situation for both fresh produce and fresh cut would be seeds, which
germinate uniform at a high percentage and subsequently grow relatively
fast to the desired size, thus, resulting in leaves of improved quality. It is
likely that such leaves will be more able to withstand the rigorous processing
that includes harvest, transportation, washing, sanitization, de-watering and
packaging. This ideal situation would both be determined by the mentioned
properties of the seeds and to a large extend the variety of the seeds. The
quality of a vegetable product is defined by the interaction of these factors
including environmental factors as well as by management and technology.
Novel, fast and non-destructive technologies for seed testing allow for new
sorting possibilities of a seed lot. At present new initiatives using
multispectral imaging and single seed NIR spectroscopy is being developed at
AU for description of seed lots. Preliminary results on investigations of Pak
Choi seeds are presented.

Use of VIS-NIR system combined with multispectral image analysis in Spinach (Spinacia oleracea L.) seed

Olesen, M. H., Carstensen, J. M., Boelt, B. — Fri, 01 Jan 2010 08:43:05 +0100

Seed health in spinach seed by multispectral imaging

Olesen, M. H., Carstensen, J. M., Boelt, B. — Fri, 01 Jan 2010 08:43:05 +0100

Multivariate classification of germinated, non-germinated and artificially aged radish and cabbage seeds using single seed near infrared reflectance spectroscopy

Min, T. G., Shetty, N., Kang, W. S., Deleuran, L. C., Olesen, M. H., Gislum, R. — Fri, 01 Jan 2010 08:43:05 +0100

Svampesygdomme i spinat - lær dem at kende

Olesen, M. H. — Fri, 01 Jan 2010 08:43:05 +0100

Udgivelsesdato: Juni 2010

Use of VIS-NIR System combined with Multispectral Image Analysis in Spinach Seed

Olesen, M. H., Carstensen, J. M., Boelt, B. — Thu, 01 Jan 2009 08:43:05 +0100