Giant reed (Arundo donax L.) is a spontaneous C3 perennial grass, which propagates only vegetatively due to seed sterility. This prevents the development and establishment of targeted improving breeding programmes. The development of mutants could improve the performance and/or suitability of the species for bioenergy production purposes, especially in stressful environments. Even though giant reed is considered a drought tolerant species, nothing is known about the effects of mutagenesis on its morpho-productive and physiological traits relevant to yield responses to drought. The objective of this study was to characterise some phenotypic traits of mutagenised giant reed under drought conditions. The trial was carried out under semi-controlled environmental conditions in a total of 16 rhizotrons of one cubic meter capacity. Calibrated soil moisture probes were installed at different depths in order to adjust the soil moisture content to 25% (field capacity) and 10% (v/v) in the wellwatered and dry treatments, respectively. A mutant (UniBO3) developed by UniBO and Genetic Lab through gamma-irradiation was selected from a pool of 100 mutants and compared with the non-mutagenised precursor of local origin. Biometric, production, and physiological parameters were evaluated at young and mature growth stages. Under wellwatered conditions at both growth stages the tiller density of UniBO3 was significantly higher than in the local genotype, but both genotypes showed similar biomass yield. The sustained biomass yield of the droughted local genotype compared with the well-watered conditions was related to unchanged number of tillers. On the other hand the reduced biomass yield of the droughted mutant (UniBO3) was significantly correlated with reductions in photosynthetic capacity (Pn), maximum carboxylation rate (Vcmax), potential electron transport rate (Jmax), quantum yield (Fv/Fm), and leaf water potential (LWP) at young stages, while at mature stages with Fv/Fm and LWP. In summary, the UniBO3 mutant showed a reduced tolerance to drought at productive and physiological levels.
Zegada-Lizarazu, W., Salvi, S., Di Girolamo Giuseppe, ., Monti, A. (2017). Drought adaptation characteristics of a giant reed mutant.
Drought adaptation characteristics of a giant reed mutant
Zegada-Lizarazu Walter;Salvi Silvio;Di Girolamo Giuseppe;Monti Andrea
2017
Abstract
Giant reed (Arundo donax L.) is a spontaneous C3 perennial grass, which propagates only vegetatively due to seed sterility. This prevents the development and establishment of targeted improving breeding programmes. The development of mutants could improve the performance and/or suitability of the species for bioenergy production purposes, especially in stressful environments. Even though giant reed is considered a drought tolerant species, nothing is known about the effects of mutagenesis on its morpho-productive and physiological traits relevant to yield responses to drought. The objective of this study was to characterise some phenotypic traits of mutagenised giant reed under drought conditions. The trial was carried out under semi-controlled environmental conditions in a total of 16 rhizotrons of one cubic meter capacity. Calibrated soil moisture probes were installed at different depths in order to adjust the soil moisture content to 25% (field capacity) and 10% (v/v) in the wellwatered and dry treatments, respectively. A mutant (UniBO3) developed by UniBO and Genetic Lab through gamma-irradiation was selected from a pool of 100 mutants and compared with the non-mutagenised precursor of local origin. Biometric, production, and physiological parameters were evaluated at young and mature growth stages. Under wellwatered conditions at both growth stages the tiller density of UniBO3 was significantly higher than in the local genotype, but both genotypes showed similar biomass yield. The sustained biomass yield of the droughted local genotype compared with the well-watered conditions was related to unchanged number of tillers. On the other hand the reduced biomass yield of the droughted mutant (UniBO3) was significantly correlated with reductions in photosynthetic capacity (Pn), maximum carboxylation rate (Vcmax), potential electron transport rate (Jmax), quantum yield (Fv/Fm), and leaf water potential (LWP) at young stages, while at mature stages with Fv/Fm and LWP. In summary, the UniBO3 mutant showed a reduced tolerance to drought at productive and physiological levels.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.