SEED GERMINATION OF SOLANUM INCANUM: AN EXAMPLE OF GERMINATION PROBLEMS OF TROPICAL VEGETABLE CROPS

Seeds of a number of locally cultivated Solanum species, notably Solanum incanum (Igbagba), are known to emerge slowly and about 30 days could be needed to attain 50% germination.

Studies were carried out to investigate the germination problems of the Solanum incanum seeds with the aim of hastening the emergence.

Decoated seeds germinated much faster than non-decoated seeds suggesting that one of the germination problems of Solanum incanum seeds is caused by their hard seed coats.
However, maximum percentage germination obtained with decoated seeds was 55%, probably due to damage to the embryo during decoating.
The decoating exercise is too laborious to be a practical recommendation.

Freshly harvested seeds are largely dormant but there is a breakdown of the dormancy in seeds which have been stored for about six months.
It appears that farmers are quite aware of this fact in that they usually sow seeds from the previous harvests and not freshly harvested seeds.

Freshly harvested seeds treated with gibberellic acid (GA, 500 ppm) for 6 days at room temperature germinated significantly better than those treated with water or untreated seeds.

The use of alternating temperatures (10°C/25°C) also had the effect of hastening the germination of the seeds.
Under these conditions the seeds gave a better rate of germination where the higher temperatures were applied for the longer period.

Symposium on Seed Problems in Horticulture

A. Joshua

https://doi.org/10.17660/ActaHortic.1978.83.20