Tag Archives: winter oilseed rape

055–068 J.A. Domínguez, J. Kumhálová and P. Novák
Assessment of the relationship between spectral indices from satellite remote sensing and winter oilseed rape yield
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Assessment of the relationship between spectral indices from satellite remote sensing and winter oilseed rape yield

J.A. Domínguez¹, J. Kumhálová²* and P. Novák³

¹UNED Department of Mathematical and Fluid Physics, Science Faculty,
C/Senda del Rey, nº9, ES280 40 Madrid, Spain
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of
Machinery Utilization, Kamýcká 129, CZ165 21 Prague, Czech Republic
³Czech University of Life Sciences in Prague, Faculty of Engineering, Department of
Agricultural Machines, Kamýcká 129, CZ165 21 Prague, Czech Republic
*Correspondence: kumhalova@seznam.cz

Abstract:

Winter oilseed rape (Brassica napus L.) belongs among the most common and strategic
crops in the Czech Republic. Growth and vitality status, yield potential and yield prediction of
oilseed rape on plots of different sizes can be effectively examined using remote sensing. That is
why the main aim of this study was to discuss a possibility of deriving spectral indices for an
assessment which spectral index is more adequate to forecast oilseed winter rape development
and consequent yield in the Czech Republic. Information about the winter oilseed rape growth
and yield was collected in three years – 2004, 2008, 2012. A relationship between grown crops
and selected vegetation indices was evaluated. The Landsat 7 satellite images were selected as a
source for deriving spectral indices. The relationship between each spectral index and yield was
analysed in 2012 only. Five images on different dates during the whole life of winter oilseed rape
were found during this year. The images from the years 2004 and 2008 were cloudier. The spectral
indices showing the best relationship with yield from 2012 were then analysed in the images from
2004 and 2008. The results showed that Enhanced Moisture Stress Index is the most acceptable
index from the selected indices used in this study. From an agronomical point of view no available
index was found to be suitable for the winter rape growth evaluation due to dependence on
precipitation conditions. For monitoring of the yield components in winter oilseed rape in
conditions of the Czech Republic, it seems necessary to develop a new vegetation index which
will reliably describe the winter oilseed rape growth stages during the whole vegetation season.

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681-686 L. Narits
Effect of nitrogen rate and application time to yield and quality of winter oilseed rape (Brassica napus L. var. oleifera subvar. biennis)
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Effect of nitrogen rate and application time to yield and quality of winter oilseed rape (Brassica napus L. var. oleifera subvar. biennis)

L. Narits

Jõgeva Plant Breeding Institute; Aamisepa 1, 48309 Jõgeva, Estonia;e-mail: Lea.Narits@jpbi.ee

Abstract:

Oilseed rape is one of the most important sources of vegetable oil in the world. Nitrogen is one of important components of oilseed rape and has strong effect on seed yield and quality. The objective of the study was to evaluate the influence of nitrogen rate and application time to yield and quality of winter oilseed rape. Field trials were carried out at the Jõgeva Plant Breeding Institute in 2007/2008 and 2008/2009. Ammonium nitrate (nitrogen content 34.4%) was used as top-fertilizer. Three different nitrogen rates: 120, 140 and 160 kg ha-1 (in active ingredient) and three different application timings were used: A) once at the beginning of spring vegetation, B) A + when the main stem was 10 cm, C) B + start of flowering in equal portions. By the results can be concluded that the amount of fertilizer had not as strong impact to seed yield and quality as fertilizer application time. The highest yields of seed and raw oil were obtained from the variant of split-N treatment (40+40+40) of 120 kg ha-1.

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548-554 E. Veromann, M. Saarniit, R. Kevväi and A. Luik
Effect of crop management on the incidence of Meligethes aeneus Fab. and their larval parasitism rate in organic and conventional winter oilseed rape
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Effect of crop management on the incidence of Meligethes aeneus Fab. and their larval parasitism rate in organic and conventional winter oilseed rape

E. Veromann, M. Saarniit, R. Kevväi and A. Luik

Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences,Kreutzwaldi 1, 51014 Tartu, Estonia; e-mail: eve.veromann@emu.ee

Abstract:

The occurrence of Meligethes aeneus adults, larvae and larval parasitism rate was studied in organic and conventional winter oilseed rape fields in Estonia. No insecticides were used in fields with either management. In the conventional field, significantly more M. aeneus adults and larvae were found than in the organic field, whereas the larval parasitism rate was significantly greater in the organic winter rape field. This study showed that organic cropping system enhanced the occurrence of parasitoids and diminished the incidence of pest attack in winter oilseed rape.

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307-310 L. Narits
Occurrence of pests and stem rot on various oil crops
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Occurrence of pests and stem rot on various oil crops

L. Narits

Jõgeva Plant Breeding Institute, Aamisepa 1, Jõgeva, 48309, Estonia;e-mail: Lea.Narits@jpbi.ee

Abstract:

The purpose of this study was to find an oil crop with no serious problems with pests and diseases, making it suitable for organic farms.The spring oilseed rape is the most important oil crop in Estonia. Winter turnip rape andwinter oilseed rape are alternatives to spring rape.In the present exploration the following were investigated: incidence of flea beetles,pollen beetles and cabbage seed weevils, and the number of blind stalks and infection of stem rot on spring oilseed rape, winter oilseed rape and winter turnip rape.In winter oilseed rape and winter turnip rape trials no pesticides and fungicides were usedduring the growing period, but there was a variant of seed treatment by ‘Rapcol’ (phurathiocarb + matalaxil + fludioxonil) in comparison with the non-treated variant. Spring oilseed rape trials were treated by ‘Rapcol’ before sowing and sprayed by ‘Fastac’ (alpha-cypermethrin) at the beginning of flowering (stage of development – 61).The following results were obtained: flea beetles appeared most on winter oilseed rape,least on winter turnip rape. Pollen beetles appeared most on spring oilseed rape, least on winter turnip rape. Most pods damaged by pollen beetles’ larvae were found on winter oilseed rape, least on winter turnip rape. Damage by cabbage seed weevil was minimal in all the oil crop trials. Stem rot infection was high on spring oilseed rape, least on winter turnip rape.By the results of exploration it can be concluded that winter turnip rape had the lowestinfection by pests and disease and therefore has good potential for sustainable agriculture.

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17–29 K. Hiiesaar, L. Metspalu, P. Lääniste, K. Jõgar, A. Kuusik and J. Jõudu
Insect pests on winter oilseed rape studied by different catching methods
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Insect pests on winter oilseed rape studied by different catching methods

K. Hiiesaar¹, L. Metspalu¹, P. Lääniste², K. Jõgar¹, A. Kuusik¹ and J. Jõudu²

¹Department of Plant Protection, Estonian Agricultural University, Kreutzwaldi 64, 51014 Tartu, Estonia; e-mail: hkelly@eau.ee
²Department of Field Crop Husbandry, Estonian Agricultural University, Kreutzwaldi 64, 51014 Tartu, Estonia

Abstract:

The distribution, species association and number of pest insects on winter oilseed rape of varieties ‘Wotan’ and ‘Express’ were studied in field experiments. Three catching methods were used: black plastic basins on the soil surface between plants, yellow flight traps filled with water at the height of the crop canopy and the shaking of plants above a plastic basin. The most abundant pest species was the pollen beetle,Meligethes aeneus, while the number of individuals from the species M. virescens in traps was much lesser. The other  important group of pest insects were weevils Ceutorrhynchus spp., the most common of which was the cabbage seed weevil, C. assimilis.  Three species of flea beetlesPhyllotreta undulata, Ph. vittata and Ph. nemorum were typical contents of traps during May. In the last decade  of May, there was a large number of thrips (Thysanoptera, Tripidae) in traps.
Winter oilseed rape began to flower to some extent later, when pest insects of cruciferous plants had ended their hibernation. Therefore, the pests first inhabited weeds and already flowering plants, from where they later moved onto winter oilseed rape.
    In the field of winter oil seed rape, chemical pest control with a pyrethroid, Fastac, did not significantly influence the abundance of  pest insects. In the last decade of May, the total number of beetles in all test variants was relatively small, but, at the beginning of June, it increased almost to an equal extent. On the basis of flight traps, heavy damage of pods could be assumed, however, only a few larvae fell into traps on the soil surface, and virtually no damaged pods were detected. Thus the spraying with Fastac had no significant effects on the number of insects caught in traps.

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