Yield stability of photoperiod-sensitive sorghum [Sorghum bicolor L. (Moench)] accessions under diverse climatic environments

Publication Type

Journal contribution

Authors

Abdulai, A.L., Parzies, H., Kouressy, M., Vaksmann, M., Asch, F., Brueck, H.

Year of publication

2012

Published in

International Journal of Agricultural Research

Band/Volume

7/

Page (from - to)

17-32

Climate variability is a characteristic feature of the tropics where the summer monsoon starts from MaylJune and ends mostly in October, thus producing an unprectably variable length of growing season. This results in serious challenges for the mainly subsistent small holder farmers in the arid to semi-arid zones of the tropics. A study was conducted to determine the attainable grain yield and yeld stability of 10 well characterized and extensively cultivated tropical sorghum accessions across 18 environments comprised of 3 dates of sowing at 3 sites (along a latitudinal gradient covering 3 agro-ecolopcal zones) over 2 years in Mali. For each year and site combination, sorghum accessions and dates of sowing were arranged in a split plot and tested in a Randomized Complete Block (RCB) design. Appropriate cultural practices and timing were used to minimize effects of biotic factors. In addition to Grain yeld, yeld penalty associated with delayed sowing was determined. Two static and five dynamic indices were used to assess the stability of grain yeld for genotypes across environments. Mean grain yeld ranged from 0 to 248 g m^-2 across environments, from 74 to 208 g m^-2 across the 10 genotypes and generally reduced with delayed sowing. A genotype combining photoperiod sensitivity and stay-green traits was revealed as the most stable. The similarities and hfferences were observed among the stability indices used in terms of ranking of the genotypes. Implications of these for adaptation to climate change are discussed