Evaluation of bread wheat populations for drought stress

Subject Areas : Crop Production Research

yosef arshad ¹ , mahdi zahravi ^{2 *} , ali soltani ³

1 - مؤسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران
2 - مؤسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران
3 - مرکز تحقیقات کشاورزی و منابع طبیعی یزد، سازمان تحقیقات، آموزش و ترویج کشاورزی، یزد، ایران

Received: 2019-09-01 Accepted : 2020-01-23 Published : 2020-02-29

Keywords: Diversity, germplasm, Gene Bank,

Abstract :

 In order to study changes of agronomic traits under drought stress and identification oftolerant germplasm, a total of 484 accessions of bread wheat collection of National PlantGene Bank were studied in Yazd field under normal and drought stress conditions byplanting tolerant cultivars (Kavir, Roshan and Mahooti). Drought stress was applied byirrigation stoppage after cultivation. Evaluation of agronomic traits was carried out inaccordance with international descriptor both for 71 drought survived accessions and thesame accessions under normal condition. Analysis of descriptive statistics showed that thegrain weight of five spikes under normal condition and the number of fertile tillers underdrought stress had the highest coefficient of variation. The highest mean reduction in traitsunder drought stress was observed for grain weight of five spikes (23.8%) and then for thenumber of fertile tillers (21.1%). In almost all traits evaluated, some accessions weresuperior to control cultivars in both normal and drought conditions. Grain weight of fivespikes under drought stress was significantly correlated with florets number per spikelet (r= 0.272*), grain number per spike (r = 0.742**), one-hundred-grain weight (r = 0.663**),grain filling period (r = 0.314**) and days to spike emergence (r = -0.238*). Theaccessions were divided into four groups under drought stress and normal conditions usingcluster analysis dendrogram. Distinction among clusters was confirmed by discriminantanalysis. The superior accessions identified in this study can be used in drought tolerancewheat breeding programs