مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

The present study examines the possibility that exogenous sulphate improve induction of cacao (T cacao) somatic embryos. The investigation was conducted on five genotypes IMC67, P7, SCA6, UPA409 and IFC5. Sulphate was supplied as K2S04 during the induction phase. Six induction media were defined: PCGo(0.000 g L-1),PCG1(1.559 g L-1), PCGz (3.118 g L-1),PCG3(6.236 g L-1),PCG4(9.354 g L-1) and PCGs (10.913 g L-1). Staminodes and petals from immature flowers buds were used as explants. In the absence (PCGo) ofK2S04, there was no embryo expression from any of the five genotypes. The percentage of embryo induction increased with the sulphate content from PCGo (negative control) to PCG3 (4 folds sulphate content compared to the positive control PCG1) dependently to genotype and the explant type. In a given Petri plate, the highest percentage of somatic embryogenesis induction was obtained with PCGz (2 folds sulphate content compared to the positive control PCG1) with: petals from IMC67 (61.410/0) and staminodes from UPA409 (87.26%), IFC (57.35%) while Sca6 (56.85%) and P7 (30.84%) were most responsive in PCG3• The probability ofthe occurrence of somatic embryos was highest in PCG2 with staminodes from IMC67 (0.55), P7 (0.57), UPA409 (0.75) and IFC5 (0.56). Sca6 genotype displayed a probability of somatic embryos induction of 0.38 when cultured on PCG3 medium. The embryos obtained were converted to plantlets. These results indicate that sulphate supply improves cacao somatic embryogenesis. The importance of sulphate metabolism in embryos differentiation is discussed.