LUCRĂRI ŞTIINŢIFICE Vol. 54 NR. 2 SERIA HORTICULTURĂ

Salicylates provided an increased yield of cucumbers with 58.0 percents
compared to the control. Similar data have been recorded for tomatoes, too, for
Leana and Madonna varieties the treatment resulted in significant production
surplus.
It is known that ortho-oxy-benzoic acid compounds (SA) with sulfur have
properties to regulate plant growth and tolerance to abiotic and biotic factors of
the external environment. In order to explore an integrated process of yield
increasing and complex resistance of plants it was followed the influence of
salicylic acid and sulfur derivatives (5-tioureidosalicylates), used in combination
with water-soluble polymers coVPNH4 and coVPK on plant growth and
development. Results are presented in table 3. Obtained experimental data argue
authentically the used substances’ proprieties to stimulate growth and primary
productivity formation of plants. The major influence ensures seed treatment with
the 5-TUS-NH4 solution of 0.0001 and 0.0005% concentration. It was recorded an
intensification of growth processes in these variants, with 39.6 and 52.3 percents
higher compared with control plants. It was noted a positive effect of 5-TUS-NH4
on cucumber plants’ productivity, in the field experience (table 3).
Table 3
The influence of BAS on crop productivity and yield structure of
cucumber plants, Icar cv.
Variant
Number
of fruits,
unit · pl. -1
The average
weight of 1
fruit, g
Production,
g · pl. -1
The yield,
kg · m 2
The
efficiency,
% control
Control 6,4 ± 0,13 68,8 ± 0,85 440,3 ± 12,1 3,96 ± 0,12 100,0
SA 6,8 ± 0,11 67,9 ± 0,56 461,7 ± 10,8 4,16 ± 0,11 105,1
5-TUS-NH4 7,7 ± 0,19 67,2 ± 0,62 517,4 ± 14,3 4,66 ± 0,14 117,7
As mentioned above, the shortage of soil water inhibits plant growth and
primary productivity, and the agronomic value part also is linearly dependent on
the saturation deficit of organs. A widely accepted way to increase resistance to
drought is considered the possibility of increasing water use efficiency by the
application of PAS. Moreover, the efficiency of water use is estimated as a
component of drought tolerance in natural systems and is considered as an
alternative way to increase it (Jones H.G., 1993). The data obtained by us (fig. 1) in
experiments conducted under conditions of drought in 2007 prove that treated
plants with SA derivatives in combination with NH4 + and K + ions coVP
copolymers are able to maintain their degree of hydration at a higher level
compared with control plants grown under accepted agricultural technology. The
property of tioureidosalicylates to adjust consumption and productive use of water
reserves in the soil, ultimately, ensures the formation of more vigorous plants and
reduces crop losses under suboptimal moisture conditions.
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