Towards an impact on food security for Tajikistan

Bread wheat (Triticum aestivum L.) is the worlds’ most important food crop and it contributes 60% of the daily protein and calories to the population of Tajikistan. This thesis evaluated protein composition and bread-making quality of wheat, presence of and response to wheat seed-borne diseases, relationships between seed-borne diseases and protein quality as well as the major constraints for high yield of good quality in the Tajik wheat production systems.High variation in protein composition, though with high heterogeneity, was found in the Tajik wheat. High Payne quality score, due to the presence of high molecular weight-glutenin subunit (HMW-GS) 5+10, was found for the majority of varieties/lines. No correlation was found between HMW-GS composition and percentage of un-extractable polymeric proteins in total polymeric protein (%UPP); also the level of the latter neither indicated strong gluten. A local adaptation and similarities with organic farming traditions seemed to prevail.Overall fourteen and eighteen fungal species, respectively, were identified in seed samples from breeders’ versus farmers’ fields. Tilletia laevis, T.tritici, Bipolaris sorokiniana and Stemphylium spp. were the major pathogenic fungi, although Alternaria spp. was the most common fungi. Wheat common bunt and loose smut were observed with low incidence in the field, though common bunt inoculum on the seed was >50%; T.laevis being the most common cause. Tajik wheat varieties and lines showed high susceptibility towards common bunt. A significant correlation was found between presence of certain fungi and protein quality. The knowledge status of the farmers was found low. Presence of seed-borne diseases, low protein content and weak gluten hampered the wheat quality, mostly independent of farm type and knowledge of farmers.To conclude, a concerted action is needed for the wheat production in Tajikistan. This thesis clearly shows a need to increase farmers’ knowledge through the use of both the educational and the agricultural extension systems. Educational activities should result in a sustainable use of certified seeds, weed and pest management, crop rotations, etc. without hampering the large biodiversity of Tajikistan. A system for use of certified seeds of novel resistant and high quality varieties also needs to be targeted within the action.