scholarly journals Seasonal occurrence of Lygus bugs on field crops in Finland

1997 ◽  
Vol 6 (5-6) ◽  
pp. 409-413 ◽  
Author(s):  
Anna-Liisa Varis
Keyword(s):  
Red Clover ◽  
Growing Season ◽  
Common Species ◽  
Winter Rye ◽  
Arable Crops ◽  
Turnip Rape ◽  
Field Crops ◽  
Spring Cereals ◽  
Long Term Survey

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.

scholarly journals Are there indications of climate change induced increases in variability of major field crops in the northernmost European conditions?

2008 ◽  
Vol 18 (3-4) ◽  
pp. 206 ◽  
Author(s):  
P. PELTONEN-SAINIO ◽  
L. JAUHIAINEN ◽  
K. HAKALA
Keyword(s):  
Solanum Tuberosum L ◽  
Growing Season ◽  
Triticum Aestivum L ◽  
Yield Variability ◽  
Hordeum Vulgare L ◽  
Major Field ◽  
Field Crops ◽  
Yield And Quality

As the northern hemisphere will experience the greatest increases in temperature and indications of climatic change are already visible in the north (in the 2000s average temperatures exceeded the long-term mean), we sought to establish if there are already signs of increased variability in yield and quality of the major field crops grown under the northernmost European growing conditions: spring and winter cereals (barley Hordeum vulgare L., oat Avena sativa L., wheat Triticum aestivum L., rye Secale cereale L.), spring rapeseed (turnip rape Brassica rapa L., oilseed rape B. napus L.), pea (Pisum sativum L.) and potato (Solanum tuberosum L.). We used long-term yield datasets of FAO for Finland (1960s to date) and MTT Agrifood Research Finland (MTT) Official Variety Trial datasets on yield and quality of major field crops in Finland since the 1970s. Yield variability was exceptionally high in the 1980s and 1990s, but previously and subsequently national yields were clearly more stable. No progressive increase in yield variability was recorded. No marked and systematic changes in variability of quality traits were recorded, except for rapeseed, which exhibited reduced variability in seed chlorophyll content. This may at least partly attribute to the differences in intensity of input use and thereby responsiveness of the crops before and after 1980 and 1990 decades. We also noted that in the 2000s average temperatures were higher than in earlier decades and this was the case for all months of the growing season except June, which represents, however, the most critical phase for yield determination in most of the field crops in Finland. Also in the 2000s precipitation increased in the first three months of the growing season and thereafter decreased, but without signs of significantly increased numbers of heavy showers (extreme rain events). Hence, in general constant, increased average temperatures during the growing seasons of the 2000s were identified, but with reduced yield variability, which was partly attributable to the diminished use of inputs, especially fertilisers.;

Long-term marketable yields of horticultural crops in southern Ontario in relation to seasonal climate

2005 ◽  
Vol 85 (2) ◽  
pp. 431-438 ◽  
Author(s):  
Alan McKeown ◽  
Jon Warland ◽  
Mary Ruth McDonald
Keyword(s):  
Growing Season ◽  
Maximum Temperature ◽  
Vegetable Crops ◽  
Vegetable Crop ◽  
Cool Season ◽  
Horticultural Crops ◽  
Field Crops ◽  
Hot Days ◽  
Before And After

In Ontario, Canada, marketable yields of certain annual horticultural crops increased steadily from 1940 to the mid-1980s, then dramatically decreased and became highly variable. This was not seen in field crops such as soybean and corn. Standard climatological variables showed little correlation with yields of vegetable crops such as tomatoes, cabbage, cauliflower, onions and rutabagas. The number of hot days (defined as days with maximum temperature greater than 30°C) and number of days with precipitation were better correlated with cool-season vegetable crop yield. With these climate measures we identified a period of milder growing season climate, from 1961 to 1986, and there was a greater frequency of hot days before and after this period. This analysis shows that horticultural crops are more sensitive to specific synoptic events, such as periods of hot days, than to overall growing season climate, and their yields may provide an indicator of a changing climate. Key words: Horticultural yields, historical climate, weather

USE OF AGRO-RESOURCE POTENTIAL OF GRAY FOREST SOILS OF UPPER VOLGA REGION

2020 ◽  
Keyword(s):  
Forest Soils ◽  
Perennial Grasses ◽  
Organic Fertilizers ◽  
Volga Region ◽  
Winter Rye ◽  
Resource Potential ◽  
Field Crops ◽  
Upper Volga ◽  
Gray Forest Soils ◽  
Winter Cereals

The results of long-term research on the influence of main indicators on their agro-resource potential are summarized on gray forest soils of the upper Volga region. For the conditions of the Vladimir Opolie, the probable yield of biomass and the main products of field crops were calculated at different coefficients ofphotosynthetic active radiation (FAR) use. Calculations of the main product yields are made taking into account the distribution of biomass to by-products and crop-root residues. For field crops of the studied crop rotations, the coefficients of precipitation utilization are estimated. They varied from 44 to 71%, depending on the crop rotation culture. On the slope of the southern exposure when cultivating winter cereals and perennial grasses, the main moisture losses were observed in the spring during snowmelt, when growing spring crops and potatoes, they were close in the autumn and spring periods. The sizes of moisture use by crops depending on the fertilizer systems for the creation of 1 C of grain units (g.u.) and from sub-arable layers are determined. In comparison with the liming background, the use of organic fertilizers reduced the water consumption coefficient from 9.6 to 8.5 mm/C g.u., their combination with a single dose of NPK - up to 7.3, and with a double dose - up to 6.8 mm / C g.u. Based on the amount of moisture used by crops, their possible yields are calculated. In spring crops, the amount of precipitation consumed (326-356 mm) corresponds to the use of 2.7-3% of the FAR and provides 54-60 C/ha of grain, in winter rye and wheat - about 4% of the FAR (yield 71-80 C/ha). In perennial grasses for 2 mowing, the moisture consumed is enough to use about 3% of the FAR., in potatoes -1.5%.

scholarly journals The Struggle of Ash—Insights from Long-Term Survey in Latvia

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 340
Author(s):  
Ilze Matisone ◽  
Roberts Matisons ◽  
Āris Jansons
Keyword(s):  
Local Density ◽  
Additive Model ◽  
Tree Height ◽  
Natural Resistance ◽  
Critical Conditions ◽  
Tree Level ◽  
Future Potential ◽  
Genetic And Environmental Factors ◽  
Long Term Survey

The dieback of common ash (Fraxinus excelsior L.) has dramatically decreased the abundance of the species in Europe; however, tolerance of trees varies regionally. The tolerance of trees is considered to be a result of synergy of genetic and environmental factors, suggesting an uneven future potential of populations. This also implies that wide extrapolations would be biased and local information is needed. Survival of ash during 2005–2020, as well as stand- and tree-level variables affecting them was assessed based on four surveys of 15 permanent sampling plots from an eastern Baltic region (Latvia) using an additive model. Although at the beginning of dieback a relatively low mortality rate was observed, it increased during the 2015–2020 period, which was caused by dying of the most tolerant trees, though single trees have survived. In the studied stands, ash has been gradually replaced by other local tree species, though some recruitment of ash was locally observed, implying formation of mixed broadleaved stands with slight ash admixture. The survival of trees was related to tree height and position within a stand (relative height and local density), though the relationships were nonlinear, indicating presence of critical conditions. Regarding temporal changes, survival rapidly dropped during the first 16 years, stabilizing at a relatively low level. Although low recruitment of ash still implies plummeting economic importance of the species, the observed responses of survival, as well as the recruitment, imply potential to locally improve the survival of ash via management (tending), hopefully providing time for natural resistance to develop.

111 Low Frequency of IBD-Related Colorectal Carcinoma in Non-Tertiary Centers: Final Results of a Nation Wide Long-Term Survey

2009 ◽  
Vol 136 (5) ◽  
pp. A-20
Author(s):  
Judith E. Baars ◽  
Ernst J. Kuipers ◽  
Ruud Beukers ◽  
Adriaan C. Tan ◽  
Bas L. Weusten ◽  
...  
Keyword(s):  
Colorectal Carcinoma ◽  
Low Frequency ◽  
Long Term Survey

scholarly journals Creating and Characterisation of New Red Clover Variety ‘Jancis’/ Sarkanâ Âboliòa Ðíirnes ‘Jancis’ Izveidoðana Un Tâs Raksturojums

2014 ◽  
Vol 68 (3-4) ◽  
pp. 180-183
Author(s):  
Biruta Jansone ◽  
Sarmīte Rancāne ◽  
Pēteris Bērziņš ◽  
Aldis Jansons
Keyword(s):  
Seed Yield ◽  
Red Clover ◽  
Climatic Conditions ◽  
Family Selection ◽  
High Dry Matter ◽  
Bright Pink ◽  
Long Stem ◽  
Dark Green ◽  
High Seed Yield

Abstract The aim of this work was to develop a red clover variety adapted to agro-climatic conditions of Latvia, suitable for different requirements of forage producers, resistant to most widespread diseases and producing high seed yield annually. Medium late ripening diploid red clover variety ‘Jancis’ was created at the LLU Research Institute of Agriculture in long-term work carried out since 1985. After free pollination of best samples of red clover collections from the VIR (St. Petersburg), individual and family selection among hybrids were carried out for approximately 20 years. Finally, best breeding line Nr. 43047 was registered as a variety ‘Jancis’. The variety is characterised by good winter hardiness, high dry matter yield (10-12 t·ha-1) and good persistence in the sward - up to 3-4 years. The variety is characterised by a long stem (90-110 cm) with 8-9 internodes, dark green leaves with a distinctive brighter picture, medium length and width of medial leaflet, and bright pink flower heads. ‘Jancis’ has stable annual seed yield in the conditions of Latvia; under favourable conditions reaching 500- 600 kg·ha-1 seeds. Since 2010, the variety ‘Jancis’ has been included in the common Latvian and EU Plant Variety Catalogue.

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