Self-pollination, intra- and interspecific crosses in tomatoes

Abstract

Tomato genotypes (Solanum spp.) have genetic variability of most desirable features, such as resistance to biotic and abiotic stresses. However, incompatibility of crosses of wild genotypes with domesticated tomatoes, or even between wild genotypes, hinders the breeding process. Thus, knowledge of the reproductive biology of genotypes and conditions is necessary to maximize the success of artificial crossings. This study evaluated the compatibility of self-pollination, intra-and interspecific controlled crosses, stigma receptivity, and pollen viability in tomato genotypes. We used two commercial genotypes S. lycopersicum ('RVTM08' and 'Redenção') and seven accessions of wild tomato genotypes ('AF 26970', 'LA-1401', 'AF 19684', 'LA-1967', 'PI-127826', 'PI-134417', and 'LA-716'). We evaluated all crosses and their reciprocals, besides the self-pollinations. The variables evaluated were fruit index (FI), number of seeds per fruit (SN), and seed germination percentage (GP). Stigma receptivity and grains' pollen viability index (PVI) were also assessed. The results showed that 'LA-1967' was self-incompatible, had a low PVI, and generated fruit without seeds in most crosses. As female parents, 'RVTM08', 'Redenção', 'AF 26970', 'LA-1401', and 'AF 19684' showed higher FI and SN. There was a wide diversity of reproductive characteristics between the genotypes and crosses that did not influence GP. Compatibility of crosses in tomatoes is determined by the female parent choice and can be affected by stigma receptivity and the PVI.

Effect of ozone sterilization on controlling leaf mildew and gray mold tomato disease in a glasshouse and its influence on other growth parameters

“…Artificial pollination is carried out at noon on sunny days as far as possible. At this time the effect is relatively good 19 …”

Cruza manual en tomate nativo (Solanum lycopersicum L.) de México como base para su mejora genética

“…Chishti et al (2021) lograron cuajado de fruto de 30.2% y 37.7% con dos y tres polinizaciones cada 24 horas ambos en temperaturas de 17 -28.6 °C. En cruzamientos realizados entre dos genotipos cultivados y siete especies silvestres Zeist et al (2022) obtuvieron variación considerable en porcentaje de cuajado de frutos y señalan la importancia de conocer la compatibilidad genética como herramienta útil para el mejoramiento genético.…”