ABSTRACT With five neotropical genera and ca. 220 species, Vochysieae is the largest tribe of Vochysiaceae, comprising more than 90 % of its species. Preliminary phylogenetic analyses with matK sequence data indicated that Vochysieae may be paraphyletic, separated into the clades QRC (Qualea, Ruizterania and Callisthene) and VS (Vochysia, Salvertia). Whether the genera and the infrageneric taxa are artificial is still controversial. In this study, we analyzed the distribution of chromosome numbers in mitotic or meiotic cells among 20 species belonging to the genera Callisthene, Qualea, Salvertia, and Vochysia, that are native and common in Central and Southeast Brazilian forests or savannas. Species of Callisthene and Qualea possessed 2n = 22, while species of Salvertia and Vochysia had 2n = 24 (or n = 12). These chromosome numbers corroborate the recognition of two groups, and also suggest that chromosome evolution based on numerical variation is conservative in these lineages.

Vochysia tucanorum Mart. (Vochysiaceae) é uma espécie amplamente distribuída em cerrado e florestas do Brasil, do estado da Bahia até o Paraná. Sua germinação foi analisada sob oito tratamentos usando diferentes condições de luz e temperatura. Até o 73 dia, pelo menos cerca de 93% das sementes germinaram em todos os tratamentos, exceto em alternância de temperaturas de 35°/10°C (62%). A luz favoreceu a germinação, exceto sob temperatura constante de 25°C, na qual as sementes não se mostraram fotoblásticas. Nesta temperatura, foi encontrada a maior porcentagem de germinação. O crescimento inicial foi analisado comparando-se os efeitos de diferentes porcentagens da luz do dia (100%, 45%, 10,6%, 4,8%), e do solo de cerrado e mata. Durante 123 dias não houve mortalidade e os cotilédones persistiram em plântulas de todos os tratamentos. Em geral, as plântulas de V. tucanorum foram indiferentes ao tipo de solo, sendo que o sombreamento parece ter promovido incremento na altura das plantas. Entretanto, a massa seca total foi maior sob a radiação de 45% da luz solar e menor sob as condições extremas utilizadas (100% ou 4,8% de pleno sol).

Vochysia tucanorum Mart. (Vochysiaceae) is a very widely distributed species in the cerrado and forests in Brazil, from the State of Bahia to Paraná. Its seed germination was analysed under eight treatments using different conditions of light and temperature. Up to 73 days, at least ca. 93% of the seeds germinated in all treatments, except under alternating temperatures of 35°/10°C (62%). Light enhanced germination, except under constant temperature of 25°C when seeds are not photoblastic. At this temperature, the highest percentage of germination was found. Initial vegetative growth was analysed by comparing the effects of shading, by means of different percentages of full daylight (100%, 45%, 10.6%, 4.8%), and soils from cerrado and forest. During 123 days, no mortality was recorded and cotyledons persisted on the seedlings of all treatments. In general, the seedlings of V. tucanorum were found to be more or less indifferent to the soil from cerrado or forest and shading seems to promote height increment. However, total dry mass was larger under a radiation of 45% full daylight and smaller under extreme conditions (100% or 4.8% full daylight).