Yield improvement of Kenyan sesame varieties

Abstract

In an effort to improve the yield of Kenyan sesame cultivars the seeds of three cultivars, SPS SIK6, SIK 096 and SPS SIK 50/1 were subjected to 300Gy, 400Gy and 600Gy of gamma rays. A first batch of seeds were subjected to these treatments in March 1994 (Experiment I) while the second batch was treated in March 1995 (Experiment II). The Mi, M2, Ms and M4 generations of experiment I and Mi generation of Experiment II were raised at the University of Nairobi Dryland Research Field Station, Kibwezi from 1994 to 1996. The M6 and M7 generations of Experiment I and M2 of Experiment II were raised at Siaya Farmer's Training Centre in 1997. The effects of radiation in Mi generation were expressed in reduced and delayed seedling emergence, reduced plant height, sectorial deformed plants, delayed flowering and extremely low yield. There was increased variation in M2 for most evaluated traits. Plants in M2 and subsequent generations were scored for a number of yield related morphological traits and days to flowering. Selection was done in the early generations for increased capsule number and earliness. As a result of selection, a total of 88 lines from M4 generation were used to derive M5 generation. Further selection in M6 generation lead to 35 lines being retained for preliminary yield trials in M7 generations.