POLLINATION:

Acca sellowiana (Berg) Burret is a predominantly allogamous species with hermaphrodite flowers that has barriers to self-fertilisation such as dichogamy by protogyny and self-incompatibility, and it´s hard to identify when self-incompatibility occurs in A. sellowiana flowers submitted to self-pollinations (Finatto et al. 2011). 

Pollinations were made using nine known self-incompatible accessions in several treatments including manual cross-pollination, manual self-pollination, no pollination and natural pollination. Flowers were pollinated and pistils collected at times ranging from 1 to 30 days after pollination (DAP) (Finatto et al. 2011).

In both cross- and self-pollinations the fertilisation occurred from 18 DAP and the zygote was visualised at 24 and 26 DAP, respectively. The abscission of the self-pollinated flowers increased from 26 DAP onwards, when significant differences (P < 0.05) were found for the percentage of abscission among self-pollinated and cross-pollinated flowers. At 30 DAP, 72% of self-pollinated flowers were abscised (Finatto et al. 2011)

The size of ovules and ovaries of self-pollinated flowers showed no significant difference from those of non-pollinated flowers throughout 30 DAP, while those from cross-pollinated flowers were significantly larger (P < 0.05) than the other treatments from 22 and 24 DAP, respectively. After 40 DAP, there was no fruit development in self-pollination and non-pollination treatments (Finatto et al. 2011)

It needs to bring greater clarity to the mechanism of self-incompatibility in A. sellowiana, indicating late-acting self-incompatibility occurring through the rejection/abscission of self-pollinated flowers precisely after syngamy and zygote formation (Finatto et al. 2011).

BIBLIOGRAPHY:
  1. FINATTO, T. DOS SANTOS, K. STEINER, N. BIZZCOCHI, L. HOLDERBAUN, D. DUCROQUET, J. GUERRA, M. & NODARI, R. Late-acting self-incompatibility in Acca sellowiana (Myrtaceae)Australian Journal of Botany [online]. 2011. [cited  2011-05-20], 59, 53–60. Available from: <http://www.publish.csiro.au/paper/BT10152.pdf>

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