Viabilty evaluation of pollen as possible indicator of high temperature tolerance in tomato genotypes

SILVA, ANDREIA CRISTINA T. FERREIRA, LEITE, IZABEL CRISTINA and BRAZ, LEILA TREVIZAN

Abstract : The objective of this research was to evaluate the behavior of five cultivars ( Carmem, IPA- 5, Principe gigante, Santa Clara TSW - 10 ) and tomato line ( CL5915), in relation to high temperature tolerance, using pollen viability. In the Experiment I the pollen was picked from different genotypes and germinated in glass slide containing Sacarose 10% and boric acid 100 mgL-1. The flowers were transferred to germination chamber with temperature regulated to 30º C, 35º C, 40ºC and 45ºC during 1, 2, 3 and 4 hours. The parameters evaluated were pollen germination and polinic tube length. In the Experiment II the genotypes were grown in greenhouse and some agronomic trairs were analyzed. Based in pollen germination in vitro technique and the percentage of fruit set during growth in greenhouse, it was verified that exposition to higher temperatures, the line CL 5915 showed the highest pollen germination percentage and polinic tube length, like Santa Clara, that was initially considered as sensitivity standard to high temperature, it was one that showed low pollen germination percentage, as well low fruit set. In another way, difference in results were observed between techniques in vivo and in vitro were not verified.

Keywords : Germination in vitro; tomato; Lycopersicum esculentum.

Rev. Bras. Fisiol. Veg., Aug. 2000, vol.12, no.2, p.156-165. full text available in Portuguese.