MD45Y - Method for selecting tomato genotypes resistant to higher temperatures - Google Patents

Abstract

The invention relates to agriculture, in particular to a method for selecting genotypes of tomatoes resistant to high temperatures. The method of selecting genotypes of high temperature resistant tomatoes includes collecting fully open flowers, separating anthers and pollen, dividing pollen into three parts, placing each part in thermostats with three temperature backgrounds: 38, 45 and 48 ° C and treating pollen at each mentioned temperature for 3, 4 and 6 hours, sowing the pollen treated on the nutrient medium, which contains, in% mass .: sucrose 15, boric acid 0.006 and the rest distilled water, and its cultivation for three hours at a temperature of 27 ° C, determination of pollen viability according to the ratio between the number of germinated pollen grains and the total number of analyzed grains, expressed as a percentage, with subsequent processing of data obtained by the method of three-factor dispersal analysis on all temperature backgrounds, the specific adaptability capacity du for the long-term action of the temperature and the specific adaptability capacity after the action of the high temperature level, being selected the genotypes that have higher determined indices.

Description

[0001] The invention relates to agriculture, in particular to a method for selecting tomato genotypes resistant to high temperatures.

[0002] The invention can be used in studying the genetics of plant adaptability and creating varieties and hybrids that possess high adaptability to high temperatures according to the viability indices of the male gametophyte.

[0003] The method of evaluating the integral and specific adaptability of sporophyte genotypes based on their cultivation on ecological media is known [1]. However, this method requires an enormous amount of work and considerable financial expenses, as a result of which unpredictable results are obtained under variable environmental conditions. At the same time, this method allows assessing the adaptability of plants only to "abstract" environmental conditions depending on the region and the conditions of the year without evidence of concrete characters and does not allow characterization of genotypes for their use in certain ecological conditions, as well as directed selection of varieties.

[0004] The problem solved by the invention consists in the possibility of evaluating the integral and specific adaptability of genotypes to high temperatures according to the viability of the male gametophyte and consists in increasing the level of authenticity in the process of improving valuable genotypes.

[0005] The method, according to the invention, includes collecting fully opened flowers, separating anthers and pollen, dividing the pollen into three parts, placing each part in thermostats with three temperature backgrounds: 38, 45 and 48°C and treating the pollen at each mentioned temperature for 3, 4 and 6 hours, sowing the treated pollen on the nutrient medium, which contains, in % mass: sucrose 15, boric acid 0.006 and distilled water the rest, and cultivating it for three hours at a temperature of 27°C, determining the pollen viability according to the ratio between the number of germinated pollen grains and the total number of analyzed grains, expressed in percentages, with subsequent processing of the data obtained by the three-factor dispersion analysis method with determining the integral adaptability capacity indices (CAI) according to the average values of pollen viability on all temperature backgrounds, the specific adaptability (CAS) after the long-term action of temperature (CAS-L) and specific adaptability capacity after the action of high temperatures (CAS-T), the genotypes with higher determined indices being selected.

[0006] The result consists in the possibility of using male gametophyte indices, such as pollen viability, to differentiate genotypes according to integral and specific adaptability, which is of great importance for the choice of components for hybridization, for the analysis of segregated populations and allows directing the selection process for obtaining varieties and hybrids resistant to high temperatures, approved taking into account ecological zones.

[0007] The given method allows to control CAI, CAS-L and CAS-T at all stages of improvement and to accelerate the process of obtaining tomato genotypes resistant to high temperatures. This method does not require considerable economic expenses and allows to evaluate a large number of different genotypes (if necessary, several hundred) and entire populations.

[0008] Embodiment of the invention

[0009] For the differentiation and selection of genotypes with integral and specific adaptability, six tomato varieties were taken: Delta, Veneţ, C-70, Victorina, Nistru and Rio-Grande, from which the fully opened flowers were collected from 15...20 plants of each variety, the anthers were removed, after which they were transferred to parchment paper packages for easy drying at a temperature of 25...26°C for 6 hours. After the expiration of the established period, the pollen was separated from the anthers by light mechanical shaking, and placed on the bottom of the package. Thus, the pollen of each genotype was divided into three parts, which were subsequently placed in a thermostat with a temperature regime of 38, 45 and 48°C. From each batch after 3, 4 and 6 hours, a portion of pollen is separated and sown in a drop of nutrient medium with the composition of 15% sucrose and 0.006% boric acid and distilled water on a glass slide. The glass with the sown pollen is placed in the Petri dish on moistened filter paper and cultivated in a thermostat at a temperature of 27°C for 3 hours. After the expiration of the established period, the germinated and ungerminated pollen grains were counted under a microscope and the pollen viability was calculated in percent. Thus, 9 indices of values P1...P9 and their errors were obtained, based on which Table 1 was compiled.

[0010] Table 1 Algorithm and pollen viability

algorithm

Pollen viability, %

Factor A, genotype

Factor B, time of action on pollen, hours

C factor, temperature, °C

P+Sp

P±Sp

P-Sp

Delta

3

38

23

20.4±2.6

17.8

45

35.7

33.5±2.2

31.3

48

43.7

40.8±2.9

37.9

4

38

23.5

21.7±1.8

19.9

45

71.5

69±2.5

66.5

48

77.6

75±2.6

72.4

6

38

39.4

36.5±2.9

33.6

45

19.8

18±1.8

16.2

48

55.4

52±3.4

48.6

alien

3

38

47.5

44.3±3.2

41.1

45

78.1

76±2.1

73.9

48

81

79±2.0

77

4

38

43.1

40.6±2.5

38.1

45

51.2

48.6±2.6

46

48

41.5

38.5±3.0

35.5

6

38

67.2

65.3±1.9

63.4

45

44.6

42.4±2.2

40.2

48

57.9

54.7±3.2

51.5

C-70

3

38

65

61.5±3.5

58

45

45.2

42.1±3.1

39

48

30.7

28.2±2.5

25.7

4

38

21

18.6±2.4

16.2

45

53.9

50.3±3.6

46.7

48

51

47±4.0

43

6

38

45.6

43±2.6

40.4

45

20.2

18±2.2

15.8

48

52.3

48.8±3.5

45.3

Victorine

3

38

70

67.7±2.3

65.4

45

60

57.5±2.5

55

48

35.8

33.1±2.7

30.3

4

38

67.1

64.7±2.4

62.3

45

66.9

64.0±2.9

61.1

48

47.7

44.7±3.0

41.7

6

38

9.7

8.5±1.2

7.3

45

31.2

28.4±2.8

25.6

48

51.4

48.4±3.0

45.4

Dniester

3

38

57.9

54.4±3.5

50.9

45

30.6

28.3±2.3

26

48

25.3

23±2.3

20.7

4

38

13.8

12±1.8

10.2

45

19.1

17±2.1

14.9

48

18

16.3±1.7

14.6

6

38

52

48.1±3.9

44.2

45

25.1

23.1±2.0

21.1

48

40.6

37.3±3.3

34.0

Rio Grande

3

38

38.5

35.0±3.5

31.5

45

22.2

20.5±1.7

18.8

48

86.6

84.7±1.9

82.8

4

38

54.3

51.6±2.7

48.9

45

49.4

46.6±2.8

43.8

48

90.0

88.2±1.8

86.4

6

38

40.8

38.7±2.1

36.6

45

57.5

55±2.5

52.5

48

72.2

69.7±2.5

67.2

[0012] After compiling the experimental data table, their computer processing was performed in a three-factor dispersion complex using the STATGRAF-plus v.2.1 program in order to establish the authenticity of the influence of each factor (genotype, duration of thermal action, temperature) and to obtain the CAI and CAS values and to establish the minimum significant difference (DMS). Based on the results obtained, it was established: the studied factors authentically influence the variability of the pollen viability index at a high level of probability (P<0.001) (table 2).

[0013] Table 2

[0014] Results of dispersion analysis in the three-factor complex

Factors and their interaction

Degree of freedom

S2 dispersion

Criterion F(f)

The F(t) criterion

Level of probability

1

2

3

4

5

6

Genotype, factor A

5

2603.6

372.9

2.3

0.0000

Duration of thermal action, factor B

2

438.5

62.8

4.82

0.0000

Temperature level, C factor

2

1697.5

243.1

4.82

0.0000

Interaction of factors A x B

10

1294.4

185.4

2.51

0.0000

Interaction of factors A x C

10

1202.7

172.2

2.51

0.0000

Interaction of factors B x C

4

958.3

137.2

3.51

0.0000

A x B x C interaction

20

779.9

111.7

1.98

0.0000

Residual dispersion

108

6.98

[0016] To highlight genotypes with specific adaptability (CAS-L) the results of the dispersion analysis of the average values of pollen viability on the backgrounds with a duration of action of 6 hours and temperatures of 38, 45, 48°C are used, at the same time the higher the values of pollen viability, the more adaptive the genotype is to the long-term action of temperature (table 3). To establish genotypes with specific adaptability (CAS-T) the results of the dispersion analysis of the average values of pollen viability on the background of a temperature of 48°C with a duration of action of 3, 4 and 6 hours are used. This criterion indicates the possibility of genotypes to withstand high temperatures, i.e. they possess specific adaptation capacity and can maintain a high level of pollen viability under these conditions (table 3).

[0017] Table 3

[0018] Indices of the adaptability capacity of genotypes (according to the results of the dispersion analysis)

genotype

repent

CAS-L at the duration of thermal action (6 hours)

CAS-T at 48°C for 3, 4, 6 hours

1

2

3

4

Delta

40.6

35.0

55.9

alien

54.4

54.1

57.4

C-70

39.7

36.6

41.3

1

2

3

4

Victorine

46.3

28.4

42.0

Dniester

28.8

36.1

25.5

Rio Grande

54.4

54.4

80.8

DMS*;1.85;2.76;2.76;[0020] * According to the results of the dispersion analysis, the DMS index is calculated - the minimum significant difference between varieties. If the difference between 2 varieties is greater than this index, the differences are significant, this fact denotes the differences of one variety from another.

[0021] As can be seen from the data in Table 3, the Veneţ and Rio-Grande varieties have similar and the highest specific adaptability capacity. The Victorina variety is truly inferior to these varieties, but for the Delta and C-70 varieties this index is authentic and significantly lower. The Nistru variety has the lowest integral adaptability. It is necessary to mention that the Veneţ and Rio-Grande varieties have a higher specific adaptability (CAS-L) and can withstand the long-term action of high temperature. According to this index, the Delta, C-70 and Nistru varieties are considerably inferior to them, but Victorina is placed in last place. According to the tolerance capacity to the action of high temperatures, the Rio-Grande variety has the highest specific adaptability capacity (CAS-T), the Veneţ and Delta varieties are inferior to it according to this index, but the lowest value of this index belongs to the Victorina, C-70 and especially Nistru varieties. Only the Rio-Grande variety possesses the three types of adaptability with the highest values.

[0022] Consequently, the proposed method allows with high authenticity the differentiation and selection of genotypes, which possess different levels of integral adaptability to high temperatures and to the solution of specific genetic and amelioration problems.

1. Кильчевский А.В., Хотылева Л.В. Ecological selection of plants. Минск, Техналогия, 1997, p. 78-82

Claims (1)

1. Method for selecting tomato genotypes resistant to high temperatures which includes collecting fully opened flowers, separating anthers and pollen, dividing pollen into three parts, placing each part in thermostats with three temperature backgrounds: 38, 45 and 48°C and treating pollen at each mentioned temperature for 3, 4 and 6 hours, sowing treated pollen on nutrient medium, which contains, in % mass: sucrose 15, boric acid 0.006 and distilled water the rest, and cultivating it for three hours at a temperature of 27°C, determining pollen viability according to the ratio between the number of germinated pollen grains and the total number of analyzed grains, expressed in percentages, with subsequent processing of the data obtained by the three-factor dispersion analysis method with determining the indices of integral adaptability capacity according to the average values of pollen viability on all temperature backgrounds, specific adaptability capacity after long-term temperature action and specific adaptability capacity after high temperature action, genotypes with higher determined indices being selected