NATIVE SPECIES OF CLOVER AND TIMOTHY-GRASS IN MOUNTAIN PHYTOCENOSIS: APPLICATION IN SELECTION FOR THE CREATION OF ECONOMIC VALUABLE FORMS - Ecological Consequences of Increasing Crop Productivity - page 6

1—very bad, when clover plants are depressed, develop poorly and fall out from
grass stand the next year;
3—bad, when after weak growth plants have few shoots on the second and third
years;
5—medium, when more than half of the plants develop well and fl ower in the year
of sowing;
7—good, when 70 percent of legume plants survive on second and third years with
good bushiness (4-5 shoots) and fl owering infl orescences;
9—very good with survival of all sown legume plants.
But legumes, including clover, in natural ecosystems usually compete with motley
grasses, which are dominant in the grass stand (above 50%). Due to this competition
many legume species drop out of the grass stand.
Newly created cultivars of meadow-pasture legume grasses undersown in moun-
tain phytocenosis have low adaptive capacity. Thus, the binary mixture with the gra-
mineous component is not effi cient enough for the selection evaluation of samples.
The aim of this study is the selection of the most adaptive plants for the complex
traits, among which the main aim is the competitiveness in the grass mixture includ-
ing gramineous component (timothy-grass) and motley grass representative ( Poterium
polygamum ).
1.2 MATERIALS AND METHODOLOGY
To achieve the mentioned aim clover and timothy-grass were sown in ratio 1:2 (one
part of clover and two parts of timothy). P. polygamum was added in the amount of
15-20 percent of clover-timothy mixture. Competitive samples of legumes were se-
lected in the second year. Those samples were considered to be competitive, which
survived. On their base a new meadow-pasture cultivar was formed.
P. polygamum belongs to family Rosaceae . This plant has high fodder qualities, a
taproot, high winter hardiness, longevity, and resistance to cold and drought. For such
qualities, it is included into the mixture of motley grasses. In the year of sowing, P. po-
lygamum develops a vigorous root system and a rosette of leaves. This helps to deter-
mine the most productive and competitive plants in the early period of development of
selection samples in collection nurseries. In the mixture with the legume-gramineous
component P. polygamum secures the high yield of forage mass.
We have included in the experiment evaluation of 18 samples of meadow clover in
the collection nursery. Zoned cultivar of red clover from North Caucasian Region—
Daryal—was used as standard. The square of each plot is 5 m 2 . The studied samples
were compared with the zoned cultivar known for its high longevity and quite stable
productivity from year to year. On each plot, we have sown the seed mixture of clover
(7.5 g), timothy-grass (4 g), and P. polygamum (2.3 g, which consists 20% of the mix-
ture of clover and timothy).
1.3 RESULTS AND DISCUSSION
The results of the experiments are summarized in Table 1.1.