Pure isolates of diseases causal organisms were obtained by the Institute experts –
immunologists according to the standard methods of V. I. Bilai [11]. The medium without
addition of FCF was the control variant in the trial. For definition samples heat resistance we
subjected callus clones to the influence of air temperature 40, 45, 50° C during 6 hours. For
selection on salt-tolerance we added 1.5 % NaCl to nutrient media. When selecting resistant to
osmotic stress material calluses were placed on the media with adding 9 and 12 %l of sucrose.
As the donor material for conducting cell breeding of vegetable crops we used the
following types of explants: for eggplant, tomato – cotyledons of 7-10 days sterile seedlings; for
carrot – somatic calluses from unfertilized seed embryos; for head cabbage – apices of 3-5 days
seedlings, for winter garlic – apical meristems. We grew explants according to
standard for crops
temperature conditions (22-24°C by 16-hours photoperiod with illumination 2 ths. luces).
Analysis of the selective factor effect on the development of explants in culture in vitro and the
first samples differentiation by its manifestation on calluses was conducted on the 16-th day of
growing. Cell breeding was conducted by 2-stage schemes of selection.
The obtained plants-regenerants were propagated, grown up, rooted and adapted to
unsterile conditions by generally known methods. Then we conducted evaluation of the level of
signs manifestation according to “The Methods of Varieties Examination on Difference,
Uniformity and Stability” (DUS) [12].
Results of investigations. We determined that on the stage of callus induction and
proliferation in primary explants of
Solanaceae crops (tomato, sweet pepper, eggplant) it is
possible to differentiate reliably samples according to the level of their resistance under field
conditions. We have revealed significant genotypic variability of vegetable crops callus clones
by their resistance to FCF of phytopathogens that allows us to select effectively perspective
genotypes by investigated signs. For explants of the eggplant of East-Asian origin optimal
conditions for conducting of cell breeding on resistance to fusarium wilt was cultivation on the
selective medium with 20 %
concentration of FCF, and for samples of West-Asian origin – 40 %
FCF. For tomato crop the effective FCF concentration of
F. oxysporum fungus for selection of
susceptible genotypes (points 4 and 3 by the worked out grading scale) is 30 % FCF. For
average
resistant and resistant samples (points 2 and 1) it is recommended to use 50 % and higher FCF
concentrations of
F. oxysporum fungus.
On the head cabbage crop there has been worked out an individual scheme of cell
breeding to fusarium wilt by which we carried out selection of
resistant morphogenic calluses, on
the breeding medium with 40 % FCF of
Fusarium oxysporum f. sp.
conglutinans. The
experiment found a significant effect of FCF in the nutrient medium on such indices of initial
explants development as vitality, regeneration frequency, morphological indices of test-tube
cabbage plants development, such as length of accidental shoots and roots. By the results of
conducted during 2011-2013 years researches among 19 investigated breeding lines of white
head cabbage there were selected resistant to FCF action mericlones of to genotypes – KN 12708
and KN 12920, which in culture in vitro showed the maximum vitality 71.4 % and 48.0 %. And
on the breeding medium with 40 % of FCF individually selected mericlones of red head cabbage
of the genotype KN 13141 were characterized by high indices of vitality and elevated level of
anthocyanins in test-tube plants.
Now the process of creation of homozygous lines, necessary for conducting of vegetable
crops heterotic breeding, remains long and labour-consuming. So, application of the
biotechnological method of gynogenesis and androgenesis in combination with cell breeding in
vitro (haploide technology) owing to the use of which it is possible to shorten considerable the
term for creation of homozygous material, resistant to pathogens, remains in the breeding of
vegetable crops. As a result of the conducted investigations on carrot cell breeding we revealed
significant effect of filtrate of culture liquid of
Alternaria radicina M. D. et E. on vitality and
proliferation of somatic and gynogenic callus clones of carrot, which allowed
to conduct material
screening on its resistance to alternaria blight. We have worked out 2-stage scheme of selection
which includes cultivation during one passage (30 days and nights)
on the breeding medium with
30 % FCF, the next passage – on the medium without selective factor and the third passage – on
40 % FCF for a harder selective selection. Due conducted for 2011-2013 years screening in
culture in vitro among somatic and gynogenic calluses of 16 carrot genotypes on resistance to
FCF
Alternaria radicina action there were selected 2 resistant to FCF of black rot gynogenic
callus clones b. k. 336 and b. k. 333, roots of which were given to join them to hybrid breeding.
For anther culture of tomato we proved the possibility of conducting cell selection on
resistance to early dry spot of tomato with the use of 20 % culture filtrate of
Alternaria solani S.
fungus. The best of created androgenic lines MK-1/1, MK-1/3, MK-1/10 by the results of
phytopathological evaluation were characterized by field resistance to alternaria blight and
classified as resistant (7 points by the grading scale CMEA). The best varieties seeds are given to
NCPGRU (3 lines) and introduced into breeding.
We also conducted exploratory research on working out laboratory methods for selection
initial breeding material of vegetable crops, that is resistant to such abiotic factors as salinity,
osmotic stress and high temperature. With the aim of obtaining breeding material with complex
resistance to diseases and abiotic factors of environment on tomato crop we conducted a number
of trials with adding as selective factor FCF of
Alternaria solani and 1 % NaCl; FCF of
Alternaria solani and 90 and 120 g/l of sucrose. As initial material we used plants ex vitro of
tomato samples resistant tо alternaria. The highest ability for callus genesis on selective media
was revealed by anther of samples with functional sterility of F
7
that confirms our opinion about
compensating character of androgenesis in tomato forms with defects of seed reproduction.
In the culture of garlic selection of drought resistant forms of collection of samples
conducted through cultivation plants - regenerants in the culture medium with 12% sucrose.
For eggplant crop we worked out the way of evaluation of samples heat resistance in
culture in vitro. We determined that the optimal temperature regime for eggplant samples
screening on heat resistance is exposure of callus clones during 6 hours to the temperature 45 °C.
Under such temperature conditions clluses viability in samples of West-Asian subspecies
decreased to 36 % whereas in East-Asian samples percentage of viability was within 61.3-76.5
%. For a more complete heat resistance evaluation of the obtained eggplant lines we conducted
their laboratory diagnosis (on leaves) by the method of F. F. Matskov [13]. The obtained results
of heat resistance evaluation coincided with those obtained in culture in vitro results that confirm
the possibility of using the above said method as an auxiliary way for establishment the heat
resistance level of eggplant samples under laboratory conditions in winter.
For savoy cabbage crop we investigated the possibility of selection of tolerant to water
deficiency genotypes on selective nutrient media in culture in vitro. The working out a speeded
up way for selection of drought-resistant genotypes was conducted by investigation the influence
of high osmotic pressure, created in the nutrient medium with the help of heightened sucrose
concentration (9 %), on the development of apical meristems culture. There were selected and
reproduced 4 mericlones, plants of which were adapted. Now we carry out seed reproduction of
the perspective material for further testing of the obtained material.
The created 28 new lines are given to breeding for testing their economical signs. By the
obtained results owing to the heightened resistance to biotic and abiotic factors in newly created
lines we observe increase in marketable yield of plants from 9.2 to 29.0 %, with
this cost price of
production reduces and the level of profitableness of vegetableness of vegetable production
growing also raises from 3.1 to 68.6 %.
Conclusions. Using of cell selection provides accelerated evaluation and selection of
resistant to biotic and abiotic factors of the original breeding material the main vegetable crops.
Resistance/tolerance newly created lines in this case is considered as an extension of the norm of
reaction, often significant, which suggests the possibility of using the developed approach for
selection form that can survive stressful conditions and successfully recover from them.