Intrapopulation variability for male gametophyte traits in the tomato F₃ and F₄ offspring derived from high temperature resistant F₂ recombinants

Relevance
Identification of forms resistant to thermal stress is important not only at the stage of search, but also later in the selection process.
Methods
The paper presents the results obtained during the studies on the variability of tomato male gametophyte traits (pollen viability, pollen tube length, pollen resistance and resistance along pollen tubes) in the hybrid F₂, F₃ and F₄ offspring derived from different crossing combinations strongly resistant to high temperature stress (8 hybrid combinations).
Results
Recombination differences expressed in the values of average variation per family (S₂) have been found in the F₂ populations segregated for a complex of pollen traits, which made it possible to isolate transgressive recombinants from different hybrid combinations, to produce seeds from them and to further perform selection cycles in F₃. It has been found that high intrapopulation variability of male gametophyte traits is preserved in F₃ and F₄ offspring, which reflects the response of their genotypes to high temperature. The offspring derived from the best F₂ recombinants has been shown to not preserve a high level of resistance in F₃ and F₄. As for the pollen heat resistance, the actual shift of the trait values in F₃ in relation to F₂ made 0.92, while it made 0.65 in F₄ in relation to F₂. The shift of the values in the dynamics of the F₂, F₃ and F₄ generations from different hybrid combinations was somewhat higher for the resistance of pollen tubes making 0.99 (F₃/F₂) and 1.15 (F₄/F₂). The most pronounced positive shift towards high values in F₃ and F₄ in relation to F₂ was recorded just in three combinations, L7 x L305, L7 x cv. Ceros, L7 x cv. Lider (R – 1.91; 1.29 and 1.08, respectively). High variability in the populations of F₄ offspring is observed for quantitative traits, as well, namely, inflorescence number per plant, flower number per inflorescence, the number of set fruits per inflorescence and seed number in fruits. The differences in the offspring diversity found during estimation of the segregating F₂ populations derived from different crossing combinations for the variability range have not been confirmed in F₃ and F₄.

1. Koshkin E.I. // Physiology of agricultural crop stability. Moscow, 2010. – 638 p. (In Russ.)

2. Tarakanov G.I., Andreeva E.N., Morev V.V. On the question of pollen response to external conditions // Development of methods for breeding and seed production in fruit and vegetable farming: // Collection of scientific papers TSHA. Moscow, 1986. – P.65-69. (In Russ.)

3. Kravchenko A.N., Lyakh V.A., Toderash L.G. and others. Methods gamete and zygote selection of tomatoes. / Edited by A.A. Zhuchenko // Mn: Chisinau, 1988. – 140 p. (In Russ.)

4. Makovei M.D. Application of the pollen assessment method in the selection of greenhouse tomato for resistance to abiotic stress factors. //Dis...PhD of agric. sciences. 01.06.05. 1992. – 197 p. (In Russ.)

5. Balashova N.N., Valeeva Z.T., Ignatov A.N. and others. On the question of the role of microgametophyte in plant adaptation to econe-mode cultivation. // J. Agricultural Biology. – 1994. – №3. – P.59-64. (In Russ.)

6. Ignatova S.I., Makovei M.D, Gorshkova N.S. Tomato selection for resistance to low light using gametophyte selection // Effective methods of growing vegetable crops (Scientific works of VNIIO). Moscow, 1998. – P.252-256. (In Russ.)

7. Fotev Yu.V., Yurlova E.V. Pollen germination rate as a criterion for assessing the adaptive capacity of tomato hybrids. // J. Agricultural Biology. – 1996. – №3. – P.46-51. (In Russ.)

8. Pivovarov V.F. Guidelines for gamete selection of agricultural plants (methodology, results and prospects) Moscow (VNIISSOK), 2001. – 386 p. (In Russ.)

9. Kovali V.S., Makarova N.N. Using gamete selection in breeding for adaptability // Problems of selection and ways to solve them in Siberia. (Reported by the message of the genetic-breeding school). Novosibirsk, 2000. – P.227-231. (In Russ.)

10. Kilchevsky A.V. Genetic-ecological bases of plant breeding // VOGiS-Bulletin. – 2005. – V.9, №4. – P.518-526. (In Russ.)

11. Bukharova A., Bukharov A. Elements of gamete and zygote selection in the practice of works on remote hybridization of tomato and pepper. // Collection papers of scientific and practical conf. "Prospects for the development of horticulture and vegetable production in the Southern Urals." Ufa, 2005. – P.101-104. (In Russ.)

12. Anokhina V. The use of gametophytic selection for differentiation of lupin tolerance to stress / V. Anokhina, V. Duksina, I Sauk //Lupin crops: an opportunity for today, a promise for the future. Proceedings of the 13th International Lupin Conference (Poznan, Polan, 6-10 June 2011). – P. 285-287.

13. Yeun-Kyung Chang, Leslie A. Blischak, Richard E. Veilleux, Muhammad J. Iqbal Effect of temperature on gametophytic selection in a Phalaenopsis F1 population //Euphytica. – 2010. – Vol.171. – Iss. 2. – P.251-261.

14. Alpatyev A.V. Michurin Basics of Tomato Breeding // Garden and Garden. – 1947. – №1. (In Russ.)

15. Ter-Avanesyan D.V. The role of the amount of pollen grains of a flower in the fertilization of plants. // Works on botany, genetics and breeding. Leningrad. – 1949. – V.28. – Issue 2. – P.119. (In Russ.)

16. Mulcahy D.L. A correlation between Gametophytic and sporophytic characteristics in Zea mays L. // Science. – 1971. – No171. – P.1155-1156.

17. Golubinsky I.N. //The biology of germination of pollen. – Kiev, 1974. – 464 p. (In Russ.)

18. Makovei M.D. The proportion of the influence of the parental components of the cross on the heritability of resistance to thermal stress in tomatoes. //Journal of Academy of Sciences of Moldova. Life Sciences. 2011. №1 (313). – P.88-94.

19. Dospehov B.A. //Methods of experimental work. Moscow: Agropromizdat, 1979. – 416 p. (In Russ.)

20. Mikhaylenko I.M., Drahavtsev V.A. Mathematical models in plant breeding. Report I. Theoretical basis for the identification of genotypes by phenotypes in the selection of fissile generations. //Journal Agricultural Biology. – 2013. – №1. – P.26-34. (In Russ.)