Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Grèce → Breeding chickpeas for high yield and seed quality under drought and heat stress conditions

University of Thessaly (UTH) 2021

Breeding chickpeas for high yield and seed quality under drought and heat stress conditions

Koskosidis, Avraam of Iakovos

Titre : Breeding chickpeas for high yield and seed quality under drought and heat stress conditions

Γενετική βελτίωση του ρεβυθιού για αντοχή στις ξηροθερμικές συνθήκες για απόδοση και χαρακτηριστικά ποιότητας του σπόρου

Auteur : Koskosidis, Avraam of Iakovos

Etablissement de soutenance : University of Thessaly (UTH)

Grade : Doctor of Philosophy (PhD) 2021

Résumé
Climate change is expected to be a major constraint for chickpea as it increases the frequency of drought and temperature extremes. This study’s aim was the development of an appropriate breeding strategy, in order to develop new, high yielding, chickpea varieties with tolerance to drought and heat stress conditions, which due to the, ongoing, climate change appears to be ofgreat interest for all the researchers, worldwide. The aim of the first study, was the development of new chickpea genotypes, with tolerance to drought and heat stress conditions. All the genotypes were sown in two different periods, one normal, according to Greece’s climatic conditions, and one off-season, in order to simulate the dominance of drought and heat stress conditions during flowering and pod-filling stages, which are the most important stages for chickpeas’ yield. During the 1st year 13 parental lines were sown, using honeycomb design (R-13), in two different sowing periods, as described above, and in two different plant densities,one in 12,8 plants/m2, which represents the condition of medium competition between plants, and one in 1,15 plants/m2, which represents the condition of zero competition between plants. The best plant of every parental line was selected, in each one of the, totally, four honeycomb design experiments. The 13 plants selected during the previous year, plus 3 new genotypes, were used in the 2nd year’s honeycomb design (R-16) experiments, which included the same two sowing periods and the same two plant densities. At the end of the 2nd year the five best single plants within each genotype were selected and were used for the 3rd year’s RCBD experiments, which were 4 in total (one for each sowing period x plant density combination). Drought and heat stress (off-season sowing) conditions resulted in significant yield reduction. Five drought resistance indices including mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (TOL), susceptible stress index (SSI) and stress tolerance index(STI) were applied on the basis of grain yield in normal and drought-heat conditions. Line 14, which was developed from genotype ‘Lemnos’, exhibited high stress tolerance, making this line a very promising genetic material for sowing under the future drought and heat stress conditions. The aim of the second study was to investigate the effect of drought and heat stress conditions on chickpeas’ quality and bioactive traits, along with antioxidant activity of the lines developed during the previous study, which were sown in normal and late sowing period, in order to achieve dry-heat conditions during the chickpea’s critical stages, and came from single plant selection in low and high plant density. Late sowing significantly affected quality traits, resulted in decreased 1000 seed weight, hydration capacity and cooking time. On the other hand, drought and heat stress conditions, resulted in increased seed coat percentage, hydration increase and proteins percentage.

Mots clés : Chickpeas ; Breeding ; Drought and heat

Présentation

Page publiée le 26 novembre 2022