Productivity and stability of the yield from common winter wheat cultivars developed at IPGR Sadovo under the conditions of Dobrudzha region

Abstract. One of the main directions of the common winter wheat breeding programs in Bulgaria is related to enhancing productivity. Since wheat is a crop of the microclimate, yield is strongly influenced by the conditions of the environment. The contemporary tendencies in the breeding of this crop are directed not only towards achieving high results with regard to productivity but also towards maintaining a relative stability of yield under changeable climatic factors. The aim of this investigation was to study the productivity and determine the stability of the yield from common winter wheat cultivars developed at the Institute for Plant and Genetic Resources (IPGR) Sadovo under the conditions of Dobrudzha region, Bulgaria. The field experiment was carried out in the trial field of Dobrudzha Agricultural Institute (DAI) during 2011 – 2013. Nineteen cultivars, breeding of IPGR, were tested in three replications. Cultivar Enola was used as a standard. The productive potential, the elements of yield and its stability were investigated. Two-factor dispersion, variation and correlation analyses were applied for statistical evaluation of the results, and the method of Kang, PCA analysis and AMMI models were involved to describe stability. With regard to vegetation period, the investigated materials did not differ from the standard cultivar Enola. They possessed typical good combination of high tillering capacity and grain weight per spike. The productivity of the studied accessions was formed mainly by these two indices. The cultivars, which realized highest yields averaged for the tree years of the investigation, were Mustang, Diamant, Tsarevets and Geya 1, and cultivars Bononya, Momchil and Lusil demonstrated stability by this trait. The optimal ratio between high productive potential and yield stability was observed in cultivars Mustang, Tsarevets, Momchil and Boryan