Flower pollen viability

McLaren NW. Changes in pollen viability and concomitant increase in the incidence of sorghum ergot with flowering date and implication in selection for escape resistance. J Phytopathol 145 261-265, 1997. 

Webber, J.E. and S.D. Ross. 1995. Flower induction and pollen viability for western larch. Pp. 395-402 in W.C. Schmidt and K.J. McDonald (compilers). Ecology and management of Larix forests A look ahead. Proceedings of an international symposium, 5-9 Oct. 1992, Whitefish, Montana. 

The viability of seeds produced by S. divinorum is questionable. It is apparently a self-sterile plant which will produce seed only when cross-pollinated (1). Valdes pollinated fourteen flowers and four produced seeds. Unfortunately, the seeds viability could not be assessed as they were accidentally killed when a growth chamber overheated (1). Generally, this plant is reproduced by cuttings. It is a diploid species (N=l 1) whose pollen grains are not as viable as those of other Salvia species. Out of 3027 pollen grains, Reisfield found that 53% aborted, although this fact alone does not explain why the plants do not set seed in Mexico (16). Even when 5. divinorum is hand pollinated, only 2 to 3 percent of the nutlets fully mature (8). 

Molybdenum deficiency results in poor and delayed flowering and reduced viability of the pollen grains, leading to reduction in fruit formation (Gubler, Grogan, and Osterli, 1982). 

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