Floral biology and phenology of sweet potato (Ipomoea batatas [L.] Lam.) in Cuba: Bases for genetic improvement

Despite the fact that some aspects related to the flowering of the sweet potato have been studied previously, to date, in Cuba and tropical regions, only general descriptions have been documented without detailed information on the biology and floral phenology of the sweet potato, aspects of interest for genetic improvement. To carry out the research, four sweet potato genotypes obtained and released by the genetic improvement program of the Research Institute of Tropical Roots and Tuber Crops (INIVIT) were selected, one of them ("CEMSA 74-228") is of international reference. The average flower emission frequency per inflorescence was 1.5 days. The number of flowers per inflorescence fluctuated between 7.35 and 26.14. The time from pollination to seed maturation varied on average from 22.8 to 32.3 days. For the four genotypes, different moments of anthesis were found, ranging from 0444 h (± 8.3 min) to 0619 h (± 10.7 min). The pollen presented viability percentages above 90% from 0600 to 1300 h. The results allowed a better knowledge of the floral biology of the sweet potato and the floral phenological phases and the approximate time of each one was determined, which will be useful for plant breeders