The influence of high temperature on the pollen viability in 23 P. sativum accessions, of early, mid-early and late groups from the collections of the Maritsa Vegetable Crops Research Institute, Plovdiv (MVCRI), and the Institute of Plant Genetic Resources K. Malkov (IPGR), Sadovo, was studied. In our preliminary study with three model pea cultivars it was found that the temperature regimes 45oS / 2 and 3 hours, close to the semi-lethal temperature for pollen viability, are suitable for selection of genotypes tolerant to high temperature. In this study, using the above temperature regimes, a negative relation was found between the treatment continuance and quantity of the reproductive organs with viable pollen, pollen germination (%), and pollen tube length (m). Among the studied accessions from MVCRI the cv. Musala (early group) maintained high quantity of the reproductive organs (70 and 44% - 2h and 3h treatments) with different pollen viability. The cv. Pulpudeva and line 2213 from the same group showed comparable response to the temperature regime 45оС/2h. The cv. Hemus (mid-early group) and cv. Uspech (late group) manifested a male gametophyte tolerant to high temperature. A genotypic differentiation in the treatment at 45оС/2h was established in the IPGR accession group. Cv. Froidure and Picardi and lines 470-26, A6BM008 and A6BM0011 had the highest potential for high temperature tolerance.
High temperature influence on the pollen viability of Pisum Sativum L. accessions