INTRODUCED FORMS OF RED CLOVER (TRIFOLIUM PRATENSE L.) OF HAYFIELD-PASTURE DIRECTION OF THE USE ON NORTH CAUCASUS - Ecological Consequences of Increasing Crop Productivity - page 19

Introduced cultivars of Belarussian selection Yaskravy, Minskiy Mutant, and Usto-
dlivy had medium indices, while T-46 and SL-38 distinguished themselves by greater
height −72.7 and 74.0 cm, respectively.
Cultivar SL-38 had the highest productivity of the green mass—3.0 kg/m² (125%
to standard), while sample Gornaya Saniba had the minimal productivity—1.1 kg/
m² (45.8% to standard) (Figure 2.5). Another native sample Dargavski also had a low
productivity of the green mass—1.5 kg/m² (62.5% to standard).
It's necessary to note that usually mountain clovers in their natural habitats have
relatively less height. The explanation is that in the conditions of vertical zoning, the
existing soil-climatic gradients lead to the formation of agrophytocenoses with maxi-
mal adaptation to sharp temperature drops, humidity, sun radiation, and eating by ani-
mals.

LSD 05 =0.28

FIGURE 2.5 Yield of green mass in red clover samples, kg/m².

Evidently, natural selection among native clover populations is in the direction of
decreasing plant height as an adaptive reaction to more economic consumption of soil
nutrients and water resources.
In our study, introduced wild samples of clover did not have low height in all
cases. In particular, sample Gornaya Saniba retained this trait in conditions of cultiva-
tion on 600 m above sea level. On the contrary, plants of sample Dargavski had larger
height than sample Gornaya Saniba. The possible explanation of this difference is the
individual type of reaction to meteo-climatic conditions of foothill zone according to
adaptive capacities of the sample. Increase of height in sample Dargavski combined
with a slight decrease of leaf number per shoot and bushiness. At the same time sample
Gornaya Saniba was lower, but had greater bushiness.