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Razlike u pravilima za ispitivanje kvaliteta semena u domaćem prometu (Pravilnik o kvalitetu semena poljoprivrednog bilja Sl. SFRJ 47/1987) i izvozu (Međunarodna pravila za ispitivanje semena-ISTA pravila) razlog su prisustva nepodudarnosti u radu prilikom ispitivanja semena i tumačenja dobijenih rezultata. Kod pojedinih biljnih vrsta se koriste i drugačije metode ispitivanja, što dodatno može dovesti do različitih rezultata o kvalitetu jedne iste partije semena. Stoga je cilj ovog rada da se istaknu razlike koje postoje i ukaže na potrebu ujednačavanja nacionalnih i međunarodnih pravila za ispitivanje semena. Kroz ovaj pregledni rad prikazane su glavne razlike prilikom uzorkovanja i najčešćih metoda ispitivanja kvaliteta semena: čistoće, klijavosti, mase 1000 semena i sadržaja vlage. Takođe su prikazane i razlike u kontroli kvaliteta uslova ispitivanja na koje laboratorije koje imaju i nacionalnu i međunarodnu akreditaciju moraju da obrate pažnju. U međunarodna ISTA pravila za ispitivanje semena unose se promene svake godine, na inicijativu laboratorija članica, na osnovu novih istraživanja i iskustava iz laboratorija širom sveta. Harmonizacija nacionalnih i međunarodnih pravila za ispitivanje semena umnogome bi olakšala rad u laboratorijama i doprinela ujednačenijim kriterijumima za ispitivanje semena i iznošenje rezultata ispitivanja., Differences in the seed testing rules for domestic trade (Regulation on the quality of seeds of agricultural plants Sl. SFRJ 47/1987) and export (International rules for seed testing - ISTA rules) are the reason for the lack of consistency in the seed testing and the interpretation of the obtained results. For certain species, there are even different test methods, which can additionally lead to inconsistent test results of the same seed lot. Therefore, the objective of this paper is to highlight the differences that exist and point out the need to harmonize national and international rules for seed testing. Through this review, the main differences during sampling and the most common methods of seed testing are shown: purity, germination, 1000 seed weight and moisture content. Differences in the quality control of test conditions are also shown, which laboratories that have both, national and international accreditation, must pay attention to. International rules (ISTA) are changed every year, at the initiative of member laboratories, based on new research and experiences from laboratories around the world. Harmonization of national and international rules for seed testing would greatly facilitate work in laboratories and contribute to uniform criteria for seed testing and reporting of test results.

Razlike u pravilima za ispitivanje kvaliteta semena u domaćem prometu (Pravilnik o kvalitetu semena poljoprivrednog bilja Sl. SFRJ 47/1987) i izvozu (Međunarodna pravila za ispitivanje semena-ISTA pravila) razlog su prisustva nepodudarnosti u radu prilikom ispitivanja semena i tumačenja dobijenih rezultata. Kod pojedinih biljnih vrsta se koriste i drugačije metode ispitivanja, što dodatno može dovesti do različitih rezultata o kvalitetu jedne iste partije semena. Stoga je cilj ovog rada da se istaknu razlike koje postoje i ukaže na potrebu ujednačavanja nacionalnih i međunarodnih pravila za ispitivanje semena. Kroz ovaj pregledni rad prikazane su glavnerazlike prilikom uzorkovanja i najčešćih metoda ispitivanja kvaliteta semena: čistoće, klijavosti, mase 1000 semena i sadržaja vlage. Takođe su prikazane i razlike u kontroli kvaliteta uslova ispitivanja na koje laboratorije koje imaju i nacionalnu i međunarodnu akreditaciju moraju da obrate pažnju. U međunarodna ISTA pravila za ispitivanje semena unose se promene svake godine, na inicijativu laboratorija članica, na osnovu novih istraživanja i iskustava iz laboratorija širom sveta. Harmonizacija nacionalnih i međunarodnih pravila za ispitivanje semena umnogome bi olakšala rad u laboratorijama i doprinela ujednačenijim kriterijumima za ispitivanje semena i iznošenje rezultata ispitivanja., Differences in the seed testing rules for domestic trade (Regulation on the quality of seeds of agricultural plants Sl. SFRJ 47/1987) and export (International rules for seed testing - ISTA rules) are reason for the lack of consistency in the seed testing and the interpretation of the obtained results. For certain species there are even different test methods, which can additionally lead to inconsistent test results of the same seed lot. Therefore, the objective of this paper is to highlight the differences that exist and point out the need to harmonize national and international rules for seed testing.Through this review, the main differences during sampling and the most common methods of seed testing are shown: purity, germination, 1000 seed weight and moisture content. Differences in the quality control of test conditions are also shown, which laboratories that have both national and international accreditation must pay attention to. International rules (ISTA) are changedevery year, at the initiative of member laboratories, based on new research and experiences from laboratories around the world. Harmonization of national and international rules for seed testing would greatly facilitate work in laboratories and contribute to uniform criteria for seed testing and reporting of test results.

High quality seed can be defined as the ability of seed to germinate vigorously and provide normal seedling and uniform crop establishment under wide range of environmental conditions. This complex trait results from a sound genetic background, good practice during seed production, favorable environment during development on the mother plant, optimal time of harvest, appropriate processing and storage. To identify seed quality marker(s) which will predict the seed quality has been a challenging task for seed researchers for a long time which has not been successfully accomplished yet. Therefore, testing germination and other traits in seed testing laboratories is still the only reliable source of information on seed quality. For commercial testing are developed standard methods aiming to provide good prediction of seedling establishment in the field. Very often, there are several standard methods developed for testing seed germination of one plant species. They can differ in germination substrate or temperature applied during the testing. In most cases, irrespective on testing conditions, seed quality will not differ significantly; however, at seed lots with declining quality testing conditions applied can be highly discriminative. Since the seed quality depends on more than one factor, it is understandable that it is not targeted in the breeding programs, however, efforts should be constant in identifying the impact of genetics on this trait and be focused on varieties which have potential in providing high seed quality.

High quality seed can be defined as the ability of seed to germinate vigorously and provide normal seedling and uniform crop establishment under wide range of environmental conditions. This complex trait results from a sound genetic background, good practice during seed production, favorable environment during development on the mother plant, optimal time of harvest, appropriate processing and storage. To identify seed quality marker(s) which will predict the seed quality has been a challenging task for seed researchers for a long time which has not been successfully accomplished yet. Therefore, testing germination and other traits in seed testing laboratories is still the only reliable source of information on seed quality. For commercial testing are developed standard methods aiming to provide good prediction of seedling establishment in the field. Very often, there are several standard methods developed for testing seed germination of one plant species. They can differ in germination substrate or temperature applied during the testing. In most cases, irrespective on testing conditions, seed quality will not differ significantly; however, at seed lots with declining quality testing conditions applied can be highly discriminative. Since the seed quality depends on more than one factor, it is understandable that it is not targeted in the breeding programs, however, efforts should be constant in identifying the impact of genetics on this trait and be focused on varieties which have potential in providing high seed quality.

From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re-establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record-keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning.

Mexico is the country with the highest number of Quercus species worldwide (157). The oaks have great ecological importance and economic potential. However, their seeds and nursery propagation have been scarcely studied. The aim of this study was to investigate the effect of nut size and color, as well as shade, on germination ofQuercus deserticola. The experiment was installed in a controlled environment chamber (25 °C/20 °C, with a photoperiod of 10 h of light). The experimental factors were nut size (small and large), color (light brown and dark brown), and shade (with and without 40% shade). The experimental design was completely randomized blocks, with the blocks nested into the shade factor. An analysis of variance with a mixed procedure and a Tukey means comparison were conducted, with the variables germinative capacity and germinative energy and a logistic model was constructed to estimate the probability of germination. There was a significant effect of seed size (p = 0.0067), seed color (p < 0.0001) and shade (p = 0.0078) on germinative capacity. The highest germinative capacity (100%) was for large seeds of dark brown color and under shade. The germinative energy (number of days to reach 70% of the germinative capacity) was affected by seed color (p < 0.0001) and by the interaction seed size*color (p = 0.0267). The highest germinative energy (11.5 days) was for large and dark brown colored seed., Resumen: México es el país más rico en especies del género Quercus del planeta, con 157 de ellas. Los encinos tienen una gran importancia ecológica y potencial económico. No obstante, sus semillas y propagación han sido poco estudiadas. El objetivo del presente trabajo fue estudiar la influencia de tamaño y color de la nuez, así como de la sombra, en la capacidad y energía germinativas de Quercus deserticola. Para ello se instaló un experimento en cámara de ambiente controlado (25 °C/20 °C), con un fotoperiodo de 10 h luz. Los factores fueron tamaño de la nuez (chica y grande), color (café claro y café oscuro) y sombra (40%) (con y sin). El diseño experimental fue en bloques al azar, anidados dentro del factor sombra. Se condujo un análisis de varianza con un modelo mixto y una comparación de medias de Tukey, para las variables capacidad germinativa y energía germinativa, y se obtuvieron los parámetros de un modelo logístico para estimar la probabilidad de germinación. Se halló un efecto significativo de tamaño (p = 0.0067) y color (p < 0.0001) de la semilla, así como de la sombra (p = 0.0078) en la capacidad germinativa. La mayor capacidad germinativa, de 100%, se logró con semilla de nuez grande, café oscuro y con sombra. De acuerdo con el análisis de varianza, la energía germinativa (número de días para alcanzar 70% de la capacidad germinativa) fue influida por el color (p < 0.0001) y por la interacción tamaño*color (p = 0.0351). La mayor energía germinativa, con un valor de 11.5 días, se alcanzó con semilla de nuez grande y café oscura.

Mexico is the country with the highest number of Quercus species worldwide (157). The oaks have great ecological importance and economic potential. However, their seeds and nursery propagation have been scarcely studied. The aim of this study was to investigate the effect of nut size and color, as well as shade, on germination ofQuercus deserticola. The experiment was installed in a controlled environment chamber (25 °C/20 °C, with a photoperiod of 10 h of light). The experimental factors were nut size (small and large), color (light brown and dark brown), and shade (with and without 40% shade). The experimental design was completely randomized blocks, with the blocks nested into the shade factor. An analysis of variance with a mixed procedure and a Tukey means comparison were conducted, with the variables germinative capacity and germinative energy and a logistic model was constructed to estimate the probability of germination. There was a significant effect of seed size (p = 0.0067), seed color (p < 0.0001) and shade (p = 0.0078) on germinative capacity. The highest germinative capacity (100%) was for large seeds of dark brown color and under shade. The germinative energy (number of days to reach 70% of the germinative capacity) was affected by seed color (p < 0.0001) and by the interaction seed size*color (p = 0.0267). The highest germinative energy (11.5 days) was for large and dark brown colored seed., Resumen: México es el país más rico en especies del género Quercus del planeta, con 157 de ellas. Los encinos tienen una gran importancia ecológica y potencial económico. No obstante, sus semillas y propagación han sido poco estudiadas. El objetivo del presente trabajo fue estudiar la influencia de tamaño y color de la nuez, así como de la sombra, en la capacidad y energía germinativas de Quercus deserticola. Para ello se instaló un experimento en cámara de ambiente controlado (25 °C/20 °C), con un fotoperiodo de 10 h luz. Los factores fueron tamaño de la nuez (chica y grande), color (café claro y café oscuro) y sombra (40%) (con y sin). El diseño experimental fue en bloques al azar, anidados dentro del factor sombra. Se condujo un análisis de varianza con un modelo mixto y una comparación de medias de Tukey, para las variables capacidad germinativa y energía germinativa, y se obtuvieron los parámetros de un modelo logístico para estimar la probabilidad de germinación. Se halló un efecto significativo de tamaño (p = 0.0067) y color (p < 0.0001) de la semilla, así como de la sombra (p = 0.0078) en la capacidad germinativa. La mayor capacidad germinativa, de 100%, se logró con semilla de nuez grande, café oscuro y con sombra. De acuerdo con el análisis de varianza, la energía germinativa (número de días para alcanzar 70% de la capacidad germinativa) fue influida por el color (p < 0.0001) y por la interacción tamaño*color (p = 0.0351). La mayor energía germinativa, con un valor de 11.5 días, se alcanzó con semilla de nuez grande y café oscura.

Graszaad is een natuurlijk product. Het wordt geproduceerd door met name akkerbouwers, die basiszaad ontvangen en dit zaaien, om hiervan vervolgens zaaizaad te oogsten dat geschikt is voor de verkoop. De meeste grassoorten hebben een koude periode nodig om tot aarvorming te komen. In de aren zit het zaaizaad dat wordt geoogst als het rijp is. Omdat het in de natuur wordt geproduceerd, waarbij de omstandigheden wisselend kunnen zijn en ook het weer van invloed is op de opbrengst en kwaliteit, is het belangrijk dat de kwaliteit die geleverd wordt in de markt voldoet aan minimale kwaliteitseisen. Deze kwaliteitseisen zijn vastgesteld in de NAK-reglementen en de NAK ziet erop toe dat ze worden nageleefd.

Causal agents of grass bunt, which infect wild grass hosts in Bromus, Festuca, Ventenata and Vulpia, are Tilletia species whose teliospores could be found in wheat seed samples too. Among them, T. bromi is morphologically similar to those of quarantined T. contraversa, and misidentification of this species could lead to commodity rejection. As a result, monitoring the presence of teliospores of quarantined species in seed samples, and identification of Tilletia species on the basis of morphological characteristics is difficult and in some cases impossible. In order to investigate the presence of grass bunt in seed samples of wheat in Vojvodina, teliospore extraction was carried out by using the size-selective sieving wash method and the OEPP/EPPO diagnostic protocol for Tilletia indica (2007). The analysis of 151 samples of basic, certified and commercial non-processed seed of wheat revealed that 127 samples were contaminated with T. caries, while 12 samples were contaminated with teliospores of Tilletia species which had morphological characteristics that correspond to T. bromi complex or quarantined T. contraversa. These teliospores displayed prominent gelatinous sheath with conspicuous depth of reticulations. Molecular identification of grass bunt teliospores was not possible in this study, because contamination level was too low (1 teliospore per 10 seeds). However, knowing that teliospores of T. bromi often occur in wheat seed samples in very low numbers there is a need for standardization of molecular techniques for the identification of a single teliospore of Tillletia species in order to make plant protection more efficient and reliable

Langs de A6, nabij Emmeloord, ligt de proef- en controleboerderij van Stichting NAK. Vanaf de snelweg zijn de proefveldjes duidelijk te zien. Wat gebeurt hier? Proefveldjes voor pootgoed, grassen en zaaizaden worden beoordeeld op rasechtheid en raszuiverheid. We gingen op bezoek bij Kees Boons, bedrijfsleider.

In 2010 the GSPP (Good Seed and Plant Practices) Hygiene Code was introduced to prevent the outbreak of Clavibacter in the production of tomatoes. Many international seed companies and a handful of propagators have since been GSPP accredited but momentum has slowed. Johan Grootscholten of Globe Plant (accredited) and Claire Peusens of the GSPP Foundation give their view on the current situation and the near future.

Ziel der vorliegenden Arbeit war es, einen Beitrag zur Aufklärung der Epidemiologie des phytopathogenen Bakteriums Acidovorax valerianellae an Feldsalat [Valerianella locusta (L.)] zu leisten, indem Untersuchungen zu Infektionsbedingungen, zur Sortenanfälligkeit, zum Übertragungsweg und Saatgutuntersuchungen durchgeführt wurden. Darauf aufbauend sollten Bekämpfungsmöglichkeiten aufgezeigt werden. Die Ergebnisse der Untersuchungen zu den Infektionsbedingungen zeigten, dass die Infektion von A. valerianellae von der Temperatur, dem Blattalter, der Inokulumdichte und der Blattnässedauer abhängig war. Eine Inokulation war bei Temperaturen zwischen 10 °C und 30 °C erfolgreich. Infizierbar waren sowohl Keim- als auch Laubblätter. Zudem war die Infektion unabhängig von der Inokulumdichte zwischen 102 cfu/ml und 107 cfu/ml möglich. Die Infektionsgeschwindigkeit und Symptomausprägung nahmen dabei zu, je höher die Temperatur, je älter die Blätter und je konzentrierter das Inokulum waren. Die Blattnässedauer beziehungsweise die relative Luftfeuchtigkeit waren für die Infektion von enormer Wichtigkeit. Bei ausschließlich trockenen Bedingungen wurde kein Befall an inokulierten Feldsalatpflanzen hervorgerufen. Ein Auftreten beziehungsweise Wiederauftreten feuchter Bedingungen nach der Inokulation förderte hingegen den Befall maßgeblich. Für eine Infektion waren fünf Stunden Blattnässedauer ausreichend. Insgesamt konnte gezeigt werden, dass eine gezielte Kulturführung mit kurzen Blattnässezeiten eine Möglichkeit zur Kontrolle des Schaderregers A. valerianellae darstellt. Alle der 13 getesteten kommerziellen Feldsalatsorten waren anfällig, die Resistenz der Wildart V. rimosa wurde hingegen bestätigt. Ein Rückgriff auf diese Wildart zum Einkreuzen mit kommerziellen Sorten erscheint geboten. A. valerianellae überdauerte einen Zeitraum von bis zu elf Monaten im Boden. Feldsalatkulturen, die unmittelbar beziehungsweise ein bis elf Monate nach infiziertem Feldsalat angebaut wurden, ware, The aim of this study was to contribute to clarifying the epidemiology of the phytopathogenic bacterium Acidovorax valerianellae on corn salad [Valerianella locusta (L.)]. To this end, research was conducted on infection conditions, cultivar sensitivities, transmission paths and seeds. Based on these results, control strategies shall be demonstrated. The tests performed under infectious conditions revealed that the infection of A. valerianellae is dependent on temperature, leaf age, inoculum concentration and leaf moisture, as well as the relative humidity. Inoculation was possible at temperatures between 10 °C and 30 °C. It was possible for leaves of any age to be infected. Moreover, infection was independent of the inoculum concentration, and occurred between 102 and 107 cfu/ml. The speed of infection and the characteristics of the symptoms increased with increasing temperature, leaf age and inoculum concentration. Both the duration of leaf moisture and the relative humidity played a crucial role in the infection process. Under dry conditions, inoculated corn salad plants developed no symptoms. However, infestation increased significantly under humid conditions or during humid periods. Five hours of leaf moisture sufficed for an infection to occur. It was demonstrated that targeted dry growth conditions with short leaf moisture periods constitute an option for controlling A. valerianellae. All 13 tested commercial corn salad cultivars were prone to A. valerianellae. However, the resistance of the wild type V. rimosa was confirmed. For this reason, it seems advisable to cross the wild type with commercial cultivars. A. valerianellae endured for up to eleven months in the soil. Some of the corn salad cultivars cultivated immediately (and one up to eleven months, respectively) after infected plants were severely infected. The number of infected plants decreased in line with increased rotting of infected old plant material. A cultivation break of at least twelve month

Zaadverbeteraar Incotec won in 2012 de India Business Award. Jan Willem Breukink, CEO, praat in De Wereld Draait Door over het succes van zijn bedrijf en van Seed Valley, een gebied in Noord-Holland waar tientallen bedrijven zijn gevestigd die zijn gespecialiseerd in de veredeling, productie en verkoop van hoogwaardige zaden en plantaardig uitgangsmateriaal. Mathijs Bouman geeft zijn economische kijk op het succes van de innovatieve zaadsector in onze krakende economie.

Zdravstveno stanje semena podrazumeva prisustvo ili odsustvo štetnih organizama prouzrokovača bolesti, kao što su gljive, bakterije i virusi, zatim prisustvo nematoda i insekata. Validne metode za ispitivanje zdravstvenog stanja semena, odobrene od strane ISTA (International Seed Testing Association) detaljno su opisane u poglavlju 7 ISTA Međunarodnih pravila za ispitivanje semena. Oni se obično zasnivaju na jednom domaćinu i jednom patogenu, ali mogu biti uključeni i multi-patogeni metodi. Stepen zaraženosti semena određuje se prema važećim propisima (Pravilnik o zdravstvenom pregledu useva i objekata za proizvodnju semena, rasada i sadnog materijala i zdravstvenom pregledu semena, rasada i sadnog materijala - Službeni glasnik RS 119/07). Za ispitivanje zdravstvenog stanja semena dostupno je više metoda koje se razlikuju po osetljivosti i ponovljivosti, dužini vremena potrebnog za njihovo izvođenje kao i po zahtevu za obukom i opremom. Koji će se metod koristiti zavisi od biljne vrste, patogena i uslova koji se ispituju i svrhe testa. Izbor metode i ocena rezultata zahtevaju znanje i iskustvo u vezi sa postojećim metodama.

Seme obeležava početak biljne proizvodnje i zato je obezbeđivanje njegovog kvaliteta prioritet savremenog semenarstva i preduslov za visoke prinose svih biljnih vrsta. Izučavanje mehanizma funkcionisanja semena, zatim redovne fiziološke, biohemijske i u novije vreme molekularne analize semenskog materijala treba da pruže uvid u kvalitet i daju čvrstu osnovu za unapređenje oplemenjivačkih programa i jačanje sistema kontrole u procesu semenske proizvodnje (Milošević et. al., 2007). Utvrđivanje kvaliteta semena vrši se primenom standardizovanih metoda, koje se menjaju u skladu sa naučnim saznanjima iz oblasti fiziologije semena. Pored toga novi tehnološki procesi dorade semena mogu da utiču na promenu metode, u skladu sa zahtevima određenih biljnih vrsta. Seme posle žetve, u procesu dorade, treba da se očisti od fizičke nečistoće, semena drugog kulturnog bilja i korova, kao i od semena lošeg kvaliteta i odredi u partije (Basra 2006). Partija je specifična količina semena, koja se fizički može identifikovati i za koju se, na osnovu toga, može izdati Sertifikat o ispitivanju. Sertifikat o ispitivanju je pokazatelj kvaliteta semena, a on obuhvata ispitivanje čistoće, klijavosti i sadržaj vlage, određivanje mase 1000 semena, ispitivanje zdravstvene ispravnosti i utvrđivanje životne sposobnosti semena. Da bi se ovi elementi utvrdili potrebno je izvršiti uzorkovanje semena.

De GSPP-code tegen Clavibacter in tomaat moet de kans verkleinen dat de gevreesde bacterieziekte ergens in de productieketen de kop op steekt. De zaadbedrijven zijn inmiddels geaccrediteerd en kunnen sinds 1 juli GSPP-zaad leveren. Ook plantenkwekers maken zich op voor een audit door Naktuinbouw. Betrokkenen uit de keten gaan in op de implicaties van de nieuwe code.

Open Dagen van Bejo Zaden in het Nederlandse Warmenhuizen met het bekijken van de demonstratievelden met groenterassen en een rondleiding door de moderne bedrijfsgebouwen voor research, zaadverwerking en verpakking. Een kijkje in het zaadtechnologisch laboratorium.

Bij een aantal gewassen is het nog problematisch om goed biologisch zaad te produceren zonder gewasbeschermingsmiddelen. Dat beperkt de beschikbaarheid en verhoogt de kosten van biologisch zaad. Onderzoek heeft kennis opgeleverd voor zaadbedrijven om de kwaliteit te verbeteren

Bij een aantal gewassen is het nog problematisch om goed biologisch zaad te produceren zonder gewasbeschermingsmiddelen. Dat beperkt de beschikbaarheid en verhoogt de kosten van biologisch zaad. Onderzoek heeft kennis opgeleverd voor zaadbedrijven om de kwaliteit te verbeteren

Recently the foundation 'Stichting Zaadgoed' has been established to further biological plant breeding in the Netherlands. The reasons (developments in conventional plant breeding; genetic engineering; EU regulations with regard to biological agriculture), and the goals of the foundation are outlined

Een bedrijfsreportage. Het bouwplan bestaat uit 25 ha pootgoed, 25 ha graszaad, 3 ha suikerbieten en 2,2 ha wintertarwe

Kwaliteitsnormen voor zaaizaad bestemd voor de internationale handel

De lelietelers hebben besloten om weer een verplichte keuring op symptoomloos lelievirus (LSV) in te voeren. De bloementelers zitten al enkele jaren met de gevolgen van schade door dit virus

Diagnostiek van het symptoomloos lelievirus (LSV)

Diagnostiek van het symptoomloos lelievirus (LSV)

Potato is an important crop in sub-tropical Southwest China, where it is double-cropped in diverse ecological systems. Yields are higher at higher elevation. Spring crops show higher yields but lower light use efficiencies than autumn crops, especially at higher altitudes. The gaps between the actual and potential yields are mainly due to insufficient utilization of radiation and low light use efficiency of the actual crops.Earlier planting in spring increased yield at 500 m asl. At 1200 m asl effects of planting time on yield were absent. In autumn, these effects were generally absent at all elevations, although plant stands were consistently and often severely reduced by early planting.For spring crops, seed tubers should be older at lower altitude and younger at higher altitude than those commonly used. For autumn crops, seed tubers should be relatively old, both at low and high altitudes. Manipulation of seed sources can be done through selecting progenies of previous spring or autumn crops produced either at low or high altitudes, or from early harvest of the seed crop. The observed long-term after-effects of seed origins may have been associated with (unknown) effects on seed health.Heavier seed tubers gave higher yields in all conditions in the range from 20 to 124 g. When numbers of sprouts were set equal per unit area, the effect of weight of seed tubers on final tuber yield per unit area was absent. Tuber numbers per stem increased as seed tuber weight decreased when the seed tubers used were young.Cutting of seed tubers generally promoted plant emergence and increased stem numbers per plant in comparison with the whole seed tuber, per unit seed weight planted; cutting also spread a wilting disease probably mainly caused by Pseudomonas solanacearum, especially at lower altitude.The results of seed or plant density in combination with the effects of planting time, seed tuber weight and intercropping showed that a denser spacing up to 10 seed tubers/m 2consi

Verslag van het veredelingsonderzoek op het Proefstation voor de Boomkwekerij te Boskoop. De belangrijkste beoordelingscriteria van 30 bestaande cultivars en 12 selecties uit het onderzoek waren: bloeirijkheid, bloemkleur, bladkwaliteit en groeiwijze

Verslag van het veredelingsonderzoek op het Proefstation voor de Boomkwekerij te Boskoop. De belangrijkste beoordelingscriteria van 30 bestaande cultivars en 12 selecties uit het onderzoek waren: bloeirijkheid, bloemkleur, bladkwaliteit en groeiwijze

Taxonomie, geografie en sortimentsbeschrijving van (24) postitief gewaardeerde Pieris japonica-cultivars en (5) hybriden. Naast namen van de niet gekeurde cultivars worden ook cultivars beschreven die geschikt zijn voor de potcultuur

Keuringsrapport van de Koninklijke Vereniging voor Boskoopse Culturen van het in Nederland gekweekte Wisteria-sortiment. Elf positief gewaardeerde cultivars worden genoemd en van een uitgebreide botanische beschrijving voorzien. De niet gekeurde cultivars worden ook genoemd. Tevens wordt aandacht besteed aan de nomenclatuur, dewinding van ranken en takken, snoei, vermeerdering, ziekten en plagen

Korte beschrijving van 20 door de Keurinscommissie van de Koninklijke Vereniging voor Boskoopse Culturen bekroonde nieuwigheden (vaste planten en sierheesters)

Overzicht van ter keuring aangeboden nieuwe planten die door de keuringscommissie van de Koninklijke Vereniging voor Boskoopse Culturen zijn beoordeeld en in 1997 met getuigschriften zijn bekroond

Hibiscus syriacus: keuringsrapport van de Koninklijke Vereniging voor Boskoopse culturen waarbij 15 positief gewaardeerde cultivars worden beschreven. De nog niet beoordeelde cultivars alsook de niet aanbevolen cultivars worden ook genoemd. In het kort teelttips met betrekking tot vermeerdering en snoei

Eerste ervaringen met de teelt en oogst van hennep

Drogestofgehalte en verteerbaarheid blijken niet de enige parameters te zijn voor kwaliteit. Eem laag lignine-gehalte is ook een belangrijke parameter. Het verhoogt de verteerbaarheid van zetmeel en zorgt vor extra eiwit in melk

Afbeeldingen in kleur met korte dendrologische beschrijving van 13 minder bekende sierheesters, die tijdens een tentoonstelling bij gelegenheid van 100 jaar keuringswerk werden geveild

Ingegaan wordt op de werking van zaadomhulling met verschillende gewasbeschermingsmiddelen tegen de uienvlieg

Bedrijfsreportage van een zaadfirma, gespecialiseerd in de zaadteelt van radijs en ijsbergsla

Een inpressie van de firma Rocalba in Noord-Spanje. Het bedrijf doet in bloembollen, bloemzaden en zaaigoed voor gazons. Daarnaast doet de onderneming in zaden voor groenvoergewassen en in plantgoed voor groenten

Special met een overzicht van het nieuwe perk-, snij-, vasteplanten- en kamerplantensortiment met een aantal bedrijfsreportages van grote vermeerderingsbedrijven in Duitsland

Van de 22 nieuwe vasteplanten-cultivars die geregistreerd staan in het Internationale vasteplantenregister werden slecht 3 cultivars door de ISU (Internationale Stauden Union) eervol onderscheiden

Door middel van een biochemische test wordt de herkomst van zaden van kerstbomen uit de Kaukasus vastgesteld

Zaadonderzoek en zaadkwaliteit, een terugblik

In a broad based study, various aspects of the control of the diseases Rhizoctonia solani and Phytophthora infestans were studied in a biological cultivation system. Experiments were carried out on organic farms. In addition a farm study was carried out in which the cultivation of seed potatoes was followed and recorded for a period of three years on 15 organic farms

The thesis describes the genetic bases of 2n-pollen formation. A comparison was made of the frequencies of 2n-pollen production in a different environment using the progeny of diallel crosses between five well-known diploid clones and three clones of Solanum phureja. It was evident that this character has a complex type of inheritance; through repeated cycles of selection for 2n-pollen a four-fold increase could be achieved at population level. Through proper selection of diploid male parents it was established that 2n-pollen genotypes can be effective for transferring useful characters, like bacterial wilt resistance, in 4x-2x crosses. The progenies derived from 4x-2x, 4x-4x and 4x-selfings were compared to find the optimal breeding approach for the production of TPS varieties. There were clear indications that it was possible to breed TPS varieties directly by 4x-2x crosses. This means that the advantages of breeding at diploid level and the effective transfer of desirable Units by 2n-gametes can be used in the TPS breeding.