Winter Turnip Rape Research Articles

THE EFFECT OF WINTER CATCH CROPS ON WEED INFESTATION IN SWEET CORN DEPENDING ON THE WEED CONTROL METHODS

An experiment was carried out in east-central Poland (52°06’ N, 22°55’ E) over 2008– 2011 to study the effect of winter catch crops on the weed infestation, number, and fresh matter of weeds in sweet corn (Zea mays L. var. saccharata). The following winter catch crops were grown: hairy vetch (Vicia villosa Roth.), white clover (Trifolium repens L.), winter rye (Secale cereale L.), Italian ryegrass (Lolium multiflorum L.) and winter turnip rape (Brassica rapa var. typica Posp.). The catch crops were sown in early September and incorporated in early May. The effect of the catch crops was compared to the effect of FYM (30 t·ha-1) and control without organic manuring (NOM). Three methods of weed control were used: HW – hand weeding, twice during the growing period, GCM – the herbicide Guardian Complete Mix 664 SE, immediately after sowing of corn seeds, Z+T – a mixture of the herbicides Zeagran 340 SE and Titus 25 WG applied at the 3–4-leaf stage of sweet corn growth. Rye and turnip rape catch crops had least weeds in their fresh matter. Sweet corn following winter catch crops was less infested by weeds than corn following farmyard manure and nonmanured corn. Least weeds and their lowest weight were found after SC, BRT and VV. LM and BRT reduced weed species numbers compared with FYM and NOM. The greatest weed species diversity, determined at the corn flowering stage, was determined after SC and FYM. The number and weight of weeds were significantly lower when chemically controlled compared with hand weeding. The best results were observed after a post-emergent application of the mixture Z+T. The weed species diversity on Z+T-treated plots was clearly lower compared with GCM and HW.

THE STRUCTURE AND YIELD LEVEL OF SWEET CORN DEPENDING ON THE TYPE OF WINTER CATCH CROPS AND WEED CONTROL METHOD

Organic manuring is suggested to be necessary in sweet corn cultivation. It is not always possible to use farmyard manure due to economic, production or technical reasons. Catch crops used as green manures can be an alternative source of organic matter. The experiment was carried out in central-east Poland (52°06’N, 22°55’E), in years 2008–2011. The successive effect of winter catch crops (hairy vetch, white clover, winter rye, Italian ryegrass, winter turnip rape) and the type of weed control on the growth and yielding of sweet corn was examined. The catch crops were sown in early September, incorporated in early May. The effect of the winter catch crops on yield was compared to the effect of FYM at a rate of 30 t·ha -1 and the control without organic manuring. The sweet corn was grown directly after organic fertilization. Three methods of weed control was used: Hw – hand weeding, twice during the growing period, GCM – herbicide Guardian CompleteMix 664 SE, immediately after sowing the seed corn, Z+T – a mixture of herbicides Zeagran 340 SE + Titus 25 WG, in the 3–4 leaf stage sweet corn. The highest yields of biomass were found for winter rye (35.5 t·ha -1 FM and 7.3 t·ha -1 DM), the most of macroelements accumulated winter turnip rape (480.2 kg N+P+K+Ca+Mg·ha -1 ). Generally, leguminous catch crops had similar to the FYM and better than non-leguminous catch crops yield-forming effect. The highest yield of marketable ears of sweet corn was obtained after FYM (14.4 t·ha -1 ) and after hairy vetch catch crop (14.0 t·ha -1 ). A similar yield-forming effect also had white clover and Italian ryegrass. The most of ears from 1 ha was achieved after white clover catch crop (59.3 tausend), similar after FYM and hairy vetch catch crop. The highest kernel yields were found after FYM (10.7 t·ha -1 ). The yields of kernel after hairy vetch and white clover catch crops were significantly higher than after nonleguminous catch crops. Z+T weed control method increase marketable yield of sweet corn (by 25–30%) and a number of ears (by 17–22%), compared to hand weeding and GCM weed control method.

Emergence and performance of volunteer oilseed rape (Brassica napus) in different crops

Volunteer oilseed rape (OSR, Brassica napus L.) causes various agronomic problems in crop rotations and can contribute to gene dispersal by pollen and by seed admixture. A 4-year field experiment (2008–2011) was set up in south-west Germany to investigate the performance of volunteers derived from two OSR cultivars with different levels of seed dormancy. Volunteers of a high-dormancy (HD) and a low-dormancy (LD) OSR cultivar were deliberately generated by spreading 10,000seedsm−2 on a field in August 2008 and 2009. Four different crops were grown on that area in the first year following the seed rain: winter wheat (Triticum aestivum L.), winter turnip rape (Brassica rapa L.), spring barley (Hordeum vulgare L.) and field pea (Pisum sativum L.). In the second year, maize (Zea mays L.) was sown uniformly across all plots. Numbers of OSR seedlings emerging in early autumn shortly after seed rain were not connected with the size of the soil seed bank in early spring of the following year. The seeds of the HD-cultivar formed a much greater soil seed bank (up to 14% of the initially spread seed number) compared with the LD-cultivar (up to 1.3%) in the soil layer of 0 to 30cm in early spring 2009 and 2010). Across all crops, considerably more volunteers of the HD-cultivar than of the LD-cultivar were present at several survey dates in the first year following seed rain. The highest number of volunteers originated from the HD-cultivar with up to 11volunteersm−2 in winter turnip rape compared with a maximum of 0.48plantsm−2 in the other crops. Cultivar-specific differences in volunteer density were observed as well in maize two years after OSR seed rain. Flowering and seed setting volunteers were only present in 2010 and the flowering time was crucially overlapping with that of sown winter OSR. The reproductive ability (seedsproducedm−2) of the LD-volunteers was five times lower in winter turnip rape than of the HD-volunteer; a similar trend was observed for the OSR volunteers in the other host crops.Strategies to definitely reduce unwanted effects of OSR volunteers, such as gene flow, should include the use of LD-cultivars with a low potential to form a soil seed bank, particularly if selective herbicides are not available, for instance in broad-leaved crops, or if the volunteers are herbicide-tolerant.

Erratum to: Winter turnip rape as a soil N scavenging catch crop in a cool humid climate

Erratum to: Winter turnip rape as a soil N scavenging catch crop in a cool humid climate

Winter turnip rape as a soil N scavenging catch crop in a cool humid climate

Leaching of nitrogen fertilizers such as nitrates from agricultural systems causes watershed eutrophication and is an economic loss for the farmer. This issue may be solved by including a catch crop in a crop rotation. For instance, winter turnip rape is a potential N catch crop for cold climates. Here, we studied winter turnip rape as a catch crop from 2009 to 2011 in Finland. Winter turnip rape was either undersown with barley in May or sown after harvesting barley in late July. In two reference treatments, the barley stubble was either left over the winter or ploughed into the soil in autumn. We collected samples from topsoil, 0-20 cm, and subsoil, 30-50 cm, in early autumn, before snowfall and in the following spring. We measured soil ammonium-N and nitrate-N, and the N content of winter turnip rape plants. Results show that undersown winter turnip rape did not change the yield and quality of barley. Winter turnip rape decreased nitrate-N in the subsoil by 83 % in 2009 and by 61 % in 2010, compared to ploughed barley. By the end of October 2009, winter turnip rape undersown in May took up 74 kg N/ha, whereas the crop sown after barley in July took up 57 kg N/ha. We conclude that winter turnip rape, either undersown with barley or sown after barley, is effective in depleting subsoil nitrates. Even though numerous reports describe the efficiency of different crucifers as catch crops under temperate climate, this is the first article concerning winter turnip rape as a catch crop under cold and humid climate.

Forage and seed yield of winter turnip rape established as a mixed crop with cereals

SUMMARYCultivation of winter turnip rape (Brassica rapa L. ssp. oleifera (DC.) Metzg.) in Finland has been limited because of its reputation as an unreliable crop and its mid-season sowing time of July, when fields are already sown to other crops. An alternative management practice for winter turnip rape is proposed whereby it would be sown as a mixed crop simultaneously with spring cereals. The growth and yield formation of winter turnip rape grown in mixed stands with four different spring cereals was studied in two field experiments conducted in 2009–11. Pure and mixed stands of winter turnip rape and spring cereals were established in May at two different cereal and winter turnip rape stand densities. Subsequent to cereal harvest, one-third of each winter turnip rape plot was harvested for biomass in autumn, before cessation of growth. Three plant stand types, May- and July-sown monocrops and a mixed crop with oat (Avena sativa L.) were sampled for forage analysis. Plant stand densities were monitored from establishment until maturity. Winter turnip rape yield and its quality, including oil content, protein content and thousand seed weight, were determined. Following favourable overwintering conditions, winter turnip rape established with cereals yielded comparably to that of pure stands in terms of both quantity and quality. However, a pure stand of winter turnip rape out-yielded mixed crop stands after unfavourable overwintering conditions. Leaf removal decreased plant survival and seed yield. Establishing winter turnip rape with a cereal in May is an alternative to sowing it as a monocrop in July. A higher seeding rate is needed for under-sown winter turnip rape. Furthermore, autumn-harvested winter turnip rape monocrop forage potentially represents a high-protein supplement for ruminants.

Serological variability among European isolates of radish mosaic virus

Serological variability of radish mosaic virus (RaMV) isolates from white mustard, winter turnip rape, Camelina sativa and Chinese cabbage, collected in the Czech Republic and Russia, was studied using antisera against the Czech isolate RaMV1. In contrast to previous studies, reasonable serological differences were found between isolates from different locations and hosts, and even between neighbouring mustard plants in the field. Serological variability of European isolates was confirmed in extended experiments involving an Italian isolate, the American Type Strain (ATS) and its homologous antiserum. The results indicate that, in Europe, RaMV isolates may occur which differ both serologically and in host plant response, but no typical strains can be defined with the methods and isolates employed so far. Camelina sativa is reported as a new host of the virus.

Weed flora and the relative importance of site, crop, crop rotation, and nitrogen

Weed species composition and density were recorded in three identical field experiments established 26 to 30 yr ago in southern Sweden. Each experiment compared three 6-yr crop rotations and four rates of nitrogen application. The rotations differed by having (1) a 2-yr rotational grassland, (2) a 2-yr mixed rotational grassland (legume/grass), or (3) spring wheat followed by fallow. Other crops in the rotations were winter turnip rape, winter wheat, spring oats, and spring barley. Using multivariate analyses, the relative importance of site, crop, crop rotation, and nitrogen application rate on the weed flora was determined. The greatest difference was found between sites, and the second most important factor was crop species. Nitrogen application rate weakly influenced the weed flora, while differences between crop rotations were hardly detectable.

Seasonal occurrence of Lygus bugs on field crops in Finland

A long term survey of Lygus populations (Heteroptera, Miridae) was carried out on eight arable crops in southern Finland. Sweep net samples were taken weekly during the growing season in 16 successive years. The hibernated adults first appeared in May on overwintered crops: winter rye, red clover-timothy ley and winter turnip rape. Turnip rape and ley harbored the most Lygus adults until the end of June even if some of them started to move to spring cereals (wheat, oats and barley), potato and sugarbeet after the emergence of these plants. The numbers of adults on cereals remained small until the crops reached the heading stage. The peak occurred in the first half of August. The adult numbers on potato and sugarbeet were also highest in August. The total number of adults was highest on wheat. Nymphs were found on all the studied crops. They were first captured in the second half of June and reached a peak between mid-July and mid-August. Numbers were highest on wheat. The most common species on all crops was L. rugulipennis Poppius, constituting 92% of the adults. The other Lygus species were L. gemellatus (Herrich-Schaeffer), L. pratensis (L.) and L. punctatus (Zetterstedt). A few specimens of L. wagneri Remane were also found.

Characteristics of a Pythium arrhenomanes with High Frequency in Barley Soils

AbstractSoils from two long‐term crop rotation experiments were examined for incidence of root pathogens with a test tube method, where a great number (hundreds) of small portions (15–68g) of soil were biotested. There was a 4–5 times higher frequency of a root‐infecting Pythium sp. In barley monoculture soil when compared to crop rotation soil, where winter turnip rape was the preceding crop. In pathogenicity tests the isolated pathogen caused severe root rot on barley, wheat and rye, but did not affect growth of oats, maize, peas and winter rape. In all essential morphological characters it resembles P. arrhenomanes and we classify it as belonging to this species.

Seed transmission of turnip yellow mosaic virus in winter turnip and winter oilseed rapes

SummaryThis is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities.The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus‐infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL‐507 0.2%, SL‐509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings.

Blossom beetle (Meligethes aeneus Fab.) as a yield factor in turnip rape (Brassica campestris L.)

Over the period from 1972—1982 the incidence of blossom beetles and their effect on yield formation in rape were studied infield trials and cage experiments at the Agricultural Research Centre, Vantaa, near Helsinki. The beetles migrated to the winter rape stands in May, when maximum daily temperatures rose above + 15°C, and the migration to the spring rape stands occurred about three weeks later. The population peak in both winter and spring rapes occurred just before flowering. During the 1970’s the diminishing cultivation of winter turnip rape, the chief host of the blossom beetle, together with an increase in the extent of spring rapes resulted in the reduction of beetle populations to such low levels that intensive control measures were not required until 1981. It appears that the blossom beetles are gradually adapting themselves to the developmental rhytm of spring turnip rape. In the cage experiments beetles were maintained on the plants a) from the seedling stage to flowering, b) from flowering to maturity and c) from the seedling stage to maturity, starting with populations of 5, 15 or 25 beetles/plant. In the first treatment the beetles had no significant effect upon yields, as the plants were able to compensate for the injuries. In the other treatments even the lowest population density reduced yields. The larvae, too, contributed to the yield loss. Apparently a vigorous stand can tolerate large numbers of beetles up to a few days before flowering, provided they are promptly destroyed after that. In the field trials, yield losses caused by natural populations of beetles ranged from 0—34 %. Even lower incidences than 2 beetles/plant caused measurable losses in yield. The injured plants produced fewer siliquas than the control plants, but tended to compensate by increasing seed number and seed weight. The trial results confirm that the threshold level, 1 beetle/plant at the early bud stage, should be followed. On the other hand they clearly demonstrate that the threshold level is essentially dependent upon the growing conditions and time of injury. For fully effective control generally two applications of insecticide are needed. The best control strategy in the future will probably involve a comprehensive regional application eg. in two to three year sequences in order to prevent the beetle populations from building up to excessive levels.

Comparative analysis of productive potential and fatty acid composition of oil from seeds of spring and winter turnip rape as perspective source for production of diesel biofuel compounds

Aim. Main aim of this research was a comparison of fatty acid composition for seed oils from of turnip rape breeding forms and varieties produced in M.M. Gryshko Natl. Botanical Garden of Natl. Academy of Sciences of Ukraine. Methods. Biochemical analysis of oil content as well as chromatographic analysis of fatty acid composition of mentioned above turnip rape genotypes were conducted out. Results. Oil content in seeds of spring (Brassica campestris f. annua D.C.) and winter (B. campestris f. biennis D.C.) turnip rape forms and varieties was determined. The highest oil content was indicated for winter variety Oriana – 38.1 %. Basing on chromatographic analysis indicated two types of fatty acid composition: high-erucic with content of 22:1 fatty acid up to 42.8 % and high-oleic with content of 18:1 fatty acid up to 46.92 %. Conclusions. Taking in account results of chromatographic analysis and agronomic productivity the best genotypes for biodiesel production were identified: winter variety Oriana and spring form EOSYaF-1. Chosen genotypes could be used for production of two different types of this biofuel – “light” and “heavy”, – according to difference in fatty acid composition.Keywords: Brassicaceae, turnip rape, spring varieties, winter vatieties, oil, fatty acids, composition, biodiesel.

The Influence of Experimentally Produced Frost on Winter Rape and Winter Turnip Rape at Bud and Flowering Stages

The Influence of Experimentally Produced Frost on Winter Rape and Winter Turnip Rape at Bud and Flowering Stages

Hardiness and Survival of Winter Rape and Winter Turnip Rape.

Hardiness and Survival of Winter Rape and Winter Turnip Rape.

Studies in F1 and F2 of crosses between winter and summer turnip rape

In the present study four hybrids between winter and summer turnip rape are compared with each other and with their parents. In all crosses the father was the same summer turnip rape, namely Mette. F1 and F2 of the hybrids were intermediate as regards their development in comparison with the parents. About three-fourths of the F1 plants of the cross Rapido X Mette, one half of F1 of the crosses Gruber X Mette and Sprengel X Mette, and only a small part of the crosses Storrybs X Mette gave seed yields. The seed yield per plant of the F1-hybrids was larger than that of the summer turnip rape Mette. The seed weight per silique and the mean seed weight were considerably higher in F2 of all the hybrids than in the summer turnip rape Mette. The green fodder production of the hybrids can be expected to be large. The hybrids seem to be usable in plant breeding work.