Evaluation of water productivity, stover feed quality and farmers? preferences on sweet sorghum cultivar types in the semi-arid regions of Zimbabwe uri icon

abstract

  • Twenty sweet sorghum cultivars that included 17improved cultivars (experimental grain, forage, dual andIndia released varieties) from India and 3 landraces fromsouthern Africa were evaluated for their use as analternative food and fodder crop for crop-livestockfarmers. The trials were conducted during 2007/08season in semi-arid conditions at Matopos ResearchStation, Zimbabwe. Three methods of assessment wereapplied to help identify suitable cultivars: grain andstover water productivity (WP), stover feed quality traitsand farmers? assessment of cultivars in the field. Grainand stover WP ranged from 0.6 to 2.7 kg m-3 and 1.2 to4.0 kg m-3 respectively. We observed significantdifferences in cultivar groups on plant height, time tomaturity, harvest index, grain WP, nitrogen uptake,nitrogen harvest index and stover metabolizable energyand digestibility (P <0.001), and sugar (Brix %) andstover WP (P <0.05). In the improved grain and dual typecultivars, grain yield increased by 118% compared tolandraces and by 69% over the forage type while in theIndia released variety type cultivars grain yield increasedby 86% compared to landrace yields and by 44% over theforage cultivars with an increase in stover yield. Thelandrace type was superior to all sweet sorghum types onfeed quality traits (metabolizable energy anddigestibility). The farmers? assessment demonstrated theneed to combine qualitative and quantitative screeningmethods. The farmers? combined analysis showed thatforage and grain yield are important parameters to thefarmers following crop-livestock production systems.Results of the three methods showed that the dual typeSP1411 was the preferred cultivar. Future breedingactivities should therefore be directed towards the tradeoff trade off between grain yield potential and stover feed qualityin the quest for developing a wider range of dual purposecultivars

publication date

  • 2011