The global warning is a crucial issue for the whole world. It will result in expansion of environmental stresses such as irreversible changes of the thermal regime, increase in radiation level, and salinization, in the areas where field crops, including wheat, are grown. Therefore, it is important that research is aimed at development of wheat varieties that are resistant to stress factors and is capable of producing optimum yield under severe environmental conditions. Development of salinity tolerant wheat varieties is of special importance for Azerbaijan since nearly 300,000 ha of arable land in the country suitable for cultivation offield crops are exposed to various levels of salinization. We have evaluated 27 varieties of 3 cereal crops (wheat, barley and triticale) under the conditions of increased soil salinity. The set ofthe varieties included 15 bread wheat, 3 durum, 6 barley, and 3 triticale varieties. TriaIs were established on saline soils characterized by sulfate and chloride- sulfate salinization. The salinity level in the topsoil ranged from 0, 144% to 1,740%, with a tendency to increase from the upper to lower layers. Because of unavailability of a salinity tolerant wheat variety, barley variety "Garabagh 22" was used as a check. Generally barley and triticale are considered as more salinity tolerant crops than wheat. However , our data suggest that salinity tolerant genotypes can be selected in wheat varieties as well and that wheat's salinity tolerance can be equal or even higher than that of barley and triticale. The study showed that bread wheat varieties possess relatively high salinity tolerance than durum wheat. However, high variability in salinity tolerance was observed in both the durum wheat and bread wheat varieties. The varieties showing susceptibility to soil salinity (i.e. salinity-sensitive varieties) were characterized by low levels of many important biological traits, such as reduced stem height (by 20 cm or more ), thin stand, and weak and low tillering that ultimately resulted ín low grain yield. On the contrary, the varieties showing tolerant reaction to soil salinity were characterized by even emergence, normal tillering and plant development, with grain yield 2.5-3.1 t/ha. Average yíeld of the salíníty tolerant varieties was hígher for 0.7 t/ha than that of the saliníty susceptible varieties íncludíng those that produce normally superior yield on the soils with optimum levels of salt content. Six bread wheat varieties (Azamatli-95, Nurlu-99, Lutenses-85, Murov-2, Murov, and Saba), 2 barley varieties (Garabagh- 7, and Garabagh-22) and 2 triticale varieties (Samur and Shírvan) were found to be relatively salínity tolerant out ofthe 27 tested varieties. Their grain yield ranged from 2.5 to 3.1 t/ha versus check variety Garabagh-22, which yíelded 2.2-2.34 t/ha. Yíeld íncrement of salíníty tolerant varieties as compared to the check varied wíthinO.16-0.76t/ha. Among the bread wheat varieties, the top yielders were Lutesee-85, Azamatlí-95 and Nurlu- 99 that yielded 3.1 t/ha, 2.88 t/ha, and 2.8 t/ha.and outyielded the check by 0.76 t/ha, 0.54 t/ha and 0.51 t/ha, respectively. Average difference ín yíeld between the salinity resistant and saliníty susceptible made up 1.12 t/ha. Thus, the study results provide evidence that salinity tolerance exists in the wheat varieties and their introduction into farming practice can increase wheat yield up to 3.0 t/ha in salíne areas of Azer- baijan.

English

0407|AGRIS 0401|AL-Wheat Program

Juan Carlos Mendieta

CIMMYT Publications Collection