scholarly journals Adaptation of silage maize varieties under extreme northern growing condions in Finland

1979 ◽  
Vol 51 (1) ◽  
pp. 197-209
Author(s):  
Seppo Pulli ◽  
P. M. A. Tigerstedt ◽  
Osmo Kara

Trials with maize varieties from various places in the world were started in 1975. In preliminary trials in 1975, 280 varieties were tested. Between 19 and 23 varieties were selected for ordinary variety tests in 1976—78 at the University farm in Siuntio. Weather conditions, particularly average daily temperatures in 1975 were better than the long term averages, and in 1976—78 far below the average growing conditions. Dry matter yields of the seven harvested silage varieties in 1975 varied between 5.8 and 11.5 tons/ha. In 1976—78 the variation in DM yields was 3.8—8.0 tons/ha among 19—23 varieties. In 1975, 44 varieties out of 280 produced mature seed. Only one variety matured in 1978, but none in 1976—77. The developmental stage of silage maize is primarily determined by ear percentage and secondarily by DM %. In 1975 the average ear % of seven varieties was 49.1 %, in 1978 18.1 % and in 1976—77 only 4.0—5.7 % in DM. As a result of the variety tests promising varieties from Yugoslavia, France and Germany could be found. It can be concluded from the long term temperature data that with very early hybrid varieties a mature grain yield can be harvested twice in ten years. Good quality silage material can be harvested six times in ten years and a satisfactory crop can be obtained eight times in then years. The limiting factor for the growth and development of maize in Finland is the low average temperature of the growing season. Important but less significant is the length of the vegetative period, which is determined by the first killing frost in the fall. The temperature deficit is particularly critical at the beginning of the growing season.

2019 ◽  
pp. 59-65
Author(s):  
V. Dryga

The aim of the study is to find out the features of forming the quality of pollen grains, namely their size and viability, depending on the growing conditions and varietal characteristics of switchgrass. The research deals with the peculiarities of millet pollen grains formation, depending on the conditions of vegetation and varietal composition, as the pollen quality – its size and viability – affects the seeds germination. It was established that the pollen quality depended both on the conditions of the growing season and varietal composition. Thus, in the 2018 growing season the weather conditions in the flowering phase (July) were favorable for the viable pollen formation, and high temperatures in August, exceeding 35 oC after 11:00 am at the absence of precipitation affected the viability of the pollen. In all the varieties, the viability of pollen was low. The most viable pollen was in the Morozko variety and the least viable – in the Cave-in-Rock variety, which negatively affected the seed germination. Pollen grains are spherical in form and colorless. They were not uniform in size both depending on the genotype and the growing conditions. In 2018 the pollen grains size ranged from 29 to 60 microns, in 2019 – from 5.2 to 57.2 microns. In 2019, the smaller pollen formed compared to 2018 due to high average daily air temperatures that exceeded average daily long-term values and due to significant moisture deficiency. Millet pollen is not homogeneous, depending on the both genotype and vegetation conditions. In 2018, which was favorable for pollen formation, the size varied from 29 to 60 microns, and in the less favorable 2019, it was smaller and ranged from 5.2 to 57.2 microns. The largest size of pollen grains formed in the Sunburst variety compared to other varieties. The most uniform – 85.3 % of the total amount – was the pollen in the Cave-in-Rock variety. Key words: pollen grains, quality, pollen size, viability, pollen form, variability, uniform.


1979 ◽  
Vol 51 (1) ◽  
pp. 210-221
Author(s):  
Seppo Pulli ◽  
Osmo Kara ◽  
P. M. A. Tigerstedt

Silage maize management studies were carried out in 1976—78 on the University farm in Siuntio in southern Finland. Seeding time trials in 1976—77 consisted of three different types of varieties seeded at four different times between May 11 and June 8. In 1978 three seeding dates were tested in relation to the seeding depth of the maize. Population density studies were carried out in 1976—77. As a result of the management studies it can be concluded that the weather conditions were so unfavorable that true differences could not be found because even the best alternative in the management technique did not give a satisfactory agronomic result. Seeding dates from May 15 to May 25 can be recommended. Relatively heavy frosts in early June (—4°C to—6° C) will hurt stands but they do not kill the plant. The advance earned with early planting is thus not totally lost through the frosts Seeding depths of 5 to 7 cm are recommended. Population densities more than 10 plants/m2 are not necessary for the maximum yield. In average or better than average growing conditions the planting densities of 6 to 8 plants/m2 could yield a more mature forage crop.


1986 ◽  
Vol 64 (11) ◽  
pp. 2405-2411 ◽  
Author(s):  
Charles R. Blem ◽  
Michael H. Shelor

Midwinter lipid depots of the white-throated sparrow (Zonotrichia albicollis) at Richmond, Virginia, are correlated with a suite of environmental and morphological variables. Lipid reserves allow this species to survive even the most extreme winter conditions for several hours. Variables having the greatest individual correlations with lipid reserve are average temperature of the 20 days prior to capture, fat class, body weight, and long-term (32-year) average temperature of the date of capture. A comprehensive multiple regression model based on analyses of all possible independent variables accounts for 87% of the variation in lipid reserves. The most important independent variables in this model are body weight, mean temperature of the 20 days preceding collection, fat class, extreme high temperature of the day of capture, long-term average temperature, relative humidity, chill factor, wet-bulb temperatures of the day before and the day of capture, wing length, and precipitation. The "best" equation using only measurements of environment as independent variables included time of collection in hours after sunrise and hours before sunset, Eastern Standard Time, temperature of the 20 days prior to capture, and mean wind velocity of the day before capture. Models computed solely from temperature measurements included dry-bulb temperatures of the day of capture and the day before capture, low extreme temperatures of the day of capture, wet-bulb temperatures of the day before capture, and the 20-day average dry-bulb temperature of the period prior to collection. Fattening in response to weather conditions appears to be a form of "fine-tuning" of energy reserves superimposed on a more stable, intrinsic cycle of winter fattening.


2016 ◽  
Vol 69 (2) ◽  
Author(s):  
David Paul Belesky ◽  
Dariusz Piotr Malinowski

Grasslands, including managed grazinglands, represent one of the largest ecosystems on the planet. Managed grazinglands in particular tend to occupy marginal climatic and edaphic resource zones, thus exacerbating responses in net primary productivity relative to changes in system resources, including anthropogenic factors. Climate dynamism, as evident from the fossil record, appears to be a putative feature of our planet. Recent global trends in temperature and precipitation patterns seem to differ from long-term patterns and have been associated with human activities linked with increased greenhouse gas emissions; specifically CO<span><sub>2</sub></span>. Thus grasslands, with their diverse floristic components, and interaction with and dependence upon herbivores, have a remarkable ability to persist and sustain productivity in response to changing resource conditions. This resistance and resilience to change, including uncertain long-term weather conditions, establishes managed grasslands as an important means of protecting food security. We review responses of grassland communities across regions of the USA and consider the responses in productivity and system function with respect to climatic variation. Research is needed to identify plant resources and management technologies that strengthen our ability to capitalize upon physiological and anatomical features prevalent in grassland communities associated with varying growing conditions.


2015 ◽  
Vol 154 (6) ◽  
pp. 1040-1050 ◽  
Author(s):  
J. SWANCKAERT ◽  
J. PANNECOUCQUE ◽  
J. VAN WAES ◽  
B. DE CAUWER ◽  
J. LATRE ◽  
...  

SUMMARYSilage maize variety testing systems usually evaluate new varieties within properly defined maturity groups; within a maturity group, all varieties are harvested on a single harvest date. In a small country like Belgium where growing conditions are similar across the maize growing areas, all tested silage maize varieties, comprising different maturity groups, are harvested on a single date. Under this testing system, only few varieties are harvested at the physiological stage where they theoretically show their optimal performance. In the current research, eight silage maize varieties were monitored from 25 to 40% whole-crop dry matter (DM) content at three locations in Belgium during the period 2007–2009. The optimal harvest date was calculated as the date where whole-crop DM yield, ear DM yield and organic matter digestibility were maximal. The variety rank at the optimal harvest date was compared with the variety rank at any studied single harvest date. Harvest dates where the variety rank was not statistically different to the rank at the optimal harvest date were pooled in a ‘harvest window’. Based on the current data, the harvest window comprised a flexible harvest period of about 14 days. It was therefore concluded that applying a single harvest date is scientifically justified for the ranking of silage maize varieties in Belgium, when the whole-crop DM content is between 28·1 and 40·6% with a maximum difference of 7·2% between all compared varieties.


1990 ◽  
Vol 62 (3) ◽  
pp. 221-226
Author(s):  
E. Varis ◽  
U. Peltola ◽  
R. Kauppila

Seed yield and overwintering of seeds of 22 Australian subterranean clover varieties were investigated in 1986 and 1987 at the Viikki Experimental Farm of the University of Helsinki. The seed yield varied remarkbly according to the variety and weather conditions of the two summers. Some varieties, such as Seaton Park, Woogenellup and Karridale, and during the summer of 1987 also the early variety Dalkeith, produced lots of seed. Some late varieties, e.g. Treeton, Tallarook and Esperance, produced very few seeds or no seeds at all. A considerable proportion of the seeds degenerated during the wet autumn conditions, by the end of October. Many seeds showed embryo dormancy, but complete dormancy or hard seeds were found only exeptionally. In spring 1988, some seedlings which had developed from overwintered burrs were found. There seems to be little hope of finding self-seeding subterranean clovers suitable for Finnish growing conditions.


2018 ◽  
Vol 48 (10) ◽  
pp. 1171-1183 ◽  
Author(s):  
Kevin G. Willson ◽  
Carson R. Barefoot ◽  
Justin L. Hart ◽  
Callie Jo Schweitzer ◽  
Daniel C. Dey

The ground flora stratum affects stand structure, resource acquisition, nutrient cycling, and taxonomic richness in forest ecosystems. Disturbances such as thinning and prescribed fire alter forest understory growing conditions that generally increase ground flora cover and richness. We studied annual changes in ground flora assemblages over three growing seasons after fire in thinned and frequently burned (3-year rotation) Pinus–Quercus stands. Our results corroborated trends from other studies that indicated greater ground flora richness and cover after thinning and burning compared with thin-only treatments. We also found that the stratum experienced relatively rapid succession between growing seasons that complimented the tolerance succession model. Forbs had reduced cover and richness from increasingly difficult growing conditions over time and were replaced by woody plants, shrubs, and seedlings. This likely occurred from changing competition dynamics that favored quick growth in the first growing season and long-term investment in vertical growth in the third growing season. The successful regeneration pathways also fit ground flora regeneration models and added a unique pathway to strengthen the predictive power of these models. As many stand management goals are focused towards improving biodiversity, prescribed fire and thinning may be used to increase understory richness in Pinus–Quercus stands.


2018 ◽  
Vol 23 ◽  
pp. 291-296
Author(s):  
O. V. Zborivska ◽  
G. O. Priadkina ◽  
O. G. Sokolovska-Sergienko ◽  
N. M. Makharinska

Aim. Estimation of the mass of dry matter of the stem of the main shoots of different varieties of winter wheat in the phases of flowering and full ripeness as a criterion for the grain productivity of its ear in years with different meteorological conditions. Methods. Field, morphometric, mathematical and statistical. Results. The mass of dry matter of the stem of the main shoots of winter wheat varieties was studied in years that differed significantly in weather conditions in the flowering phase and at full grain maturity. It was established that the mass of dry matter of the stem of the main shoot at the flowering and the full grain maturity varied significantly, respectively 0.6–1.2 g and 0.5–1.0 g in 2014, and 1.0–2.0 g and 0.8–1.5 g in 2016 depending on the variety, and under different growing conditions. Limits of variation of grain yield of the ear in 2014, ranged from 0.9 to 2.2 g and from 1.5 to 2.5 g in 2016. It was established that at the flowering, the correlation between the mass of grain from the head and the mass of the dry substance of the stem was significant at 99 % probability under growing conditions (r = 0.8–0.9). Conclusions. It is shown that grain productivity of main shoot in winter wheat is related to the ability of its stem to store assimilates during the vegetative period. It was established that the mass of the dry matter of the stem of the main shoots in the flowering phase can serve as a criterion for assessing its grain productivity. Keywords: Triticum aestivum L., mass of stem, grain yield.


Author(s):  
Marina Evgenievna Belyshkina ◽  
Tamara Petrovna Kobozeva ◽  
Elena Vasilevna Gureyeva

Based on long-term data, the article considers the peculiarities of growth and development of soybean varieties of the Northern ecotype depending on the conditions of the growing season and the influence of limiting factors. The need of soy plants for heat and moisture increases from seed germination to germination, then to the phases of flowering and bean formation, while their uniform distribution is important. In the absence of abnormal periods of drought or waterlogging, soybean varieties of the Northern ecotype Mature in August – early September. The purpose of the research was to determine the degree of influence of variability of agrometeorological conditions of the vegetation period in different years on the production process of soybean varieties of the Northern ecotype and to assess the possibility of their cultivation in the Ryazan and other regions of the Central district of the Non-Chernozem zone. The experiments were carried out in 2009–2019 years with varieties of soya of Northern ecotype Mahewa, Bright and the Whale. The limiting factor in some years of research in the conditions of the Ryazan region was the lack of moisture, while the biological minimum temperatures were maintained at all stages of growth and development. As a result of the analysis of the average annual temperature and precipitation data, the most favorable conditions for the cultivation of all the studied soybean varieties for seeds are formed in the Bryansk, Oryol and Ryazan regions. For Vladimir, Ivanovo, Kaluga, Moscow, Smolensk and Tula regions, the varieties Kasatka and Mageva are recommended, for Kostroma, Tver, and Yaroslavl – Kasatka. In all areas of the Central region of the Non-Chernozem zone, these varieties can be used to obtain green mass, silage and haylage.


2017 ◽  
Vol 12 (2) ◽  
pp. 64-69
Author(s):  
Радик Сафин ◽  
Radik Safin ◽  
Газимзян Шарафутдинов ◽  
Gazimzyan Sharafutdinov ◽  
Вероника Решетняк ◽  
...  

The article presents the results of studies on the evaluation of various factors influence on the formation of a complex of qualitative characteristics of seeds. Differences in the indexes of seed quality were established, depending on their weight, position on the ear and varietal features. The differences in the total DNA of the epiphytic microflora of seeds of different varieties are revealed. The largest and most qualitative seeds were formed in the middle part of the ear. Dependences of qualitative characteristics of seeds on the conditions of moisture content of the growing season are determined. The greatest dependence of laboratory germination in the spring was on the conditions of moistening in June of the growing of seeds. The use of different seeding rates, varieties and seed treatment has a pronounced effect on seed quality. The greatest influence on the indicator of laboratory germination was provided by the weather conditions of the vegetative period and the interaction of the variety, the rate of seeding and seed treatment. The maximum germination values were in seed treatment before seeding with Kinto Duo fungicide with the addition of Albit and a seeding rate of 5.0 million germinating seeds per hectare.


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