PHENOLOGICAL BEHAVIOR OF TWO NEW MALE CULTIVARS OF PISTACHIO (PISTACIA VERA L.): 'CHAPARRILLO' AND 'GUERRERO'

In the present work, the phenology of eight female and ten male pistachio (P. vera L.) cultivars has been characterized, including the first data of agronomic behavior of two new male cultivars obtained recently: ‘Guerrero’ and ‘Chaparrillo’. A phenological synchronization index (FSI) between male and female cultivars has been determined, which will help to find the best choosing between all the different possible combinations. The experiment was conducted at the El Chaparrillo Research Station, Ciudad Real, Spain (3°56’W, 39°0’N; altitude 640 m). For this characterization of the cultivars in study, four leading phenological stages (Guerrero et al., 2008) were taken into account: initial movement, beginning, full and end of flowering period. Data have been collected during seven years. It is noteworthy ‘C-Especial’ and ‘M-38’ male cultivars as more universal to present higher rates of overlap in pollination with most female cultivars under study. The exception is marked by late flowering males, such as ‘Peter’ and ‘02-18’, being the most common for late flowering female cultivar ‘Kerman’. However, the best flowering overlaps are obtained with the two new males ‘Guerrero’ and ‘Chaparrillo’, with an FSI above 0.8 with that female cultivar. Finally, considering that annual climatic differences affect the phenology of each cultivar also differently, it is believed that combining different male cultivars with different flowering dates is recommended to ensure maximum overlap with the female cultivar.