Atsako į druskingumo stresą skirtumai Lolium multiflorum diploidinių bei tetraploidinių augalų dygimo ir vegetatyvinio augimo tarpsniais

Abstract

Soil salinity is a global challenge emanating from climatic changes, depletion of fresh water reserves and extensive irrigation practices among other factors. Soil salinization still remains a huge concern in the realization of sustainable agricultural production. While emphasis has been placed on the food crops, forage production, which is an important component of the food chain, is affected as well. The aim of this study was to evaluate the morphological and physiological response to salinity stress in diploid cultivars and auto-induced tetraploid lines of annual ryegrass (Lolium multiflorum spp. multiflorum). Diploid seeds and their induced tetraploid counterparts were germinated on filter paper moistened with different concentrations of sodium chloride (NaCl) solutions, and seedlings were treated with 500 mM NaCl for 10 days in controlled conditions. The effect of different salt concentrations on germination and seedlings was studied. Results showed that seeds from the induced tetraploid lines despite being bigger had higher germination index and lower median germination time (T50) values compared to the diploid progenitors. At the seedling stage, increase in the ploidy level had a role in conferring improved tolerance to salinity stress. The induced tetraploid lines had an advantage over their diploid counterparts as the induced tetraploid lines had significant reduction in their growth in response to salinity stress, higher relative water content and antioxidant activities.

A Comparison of Germination Responses on Italian Ryegrass (diploid vs tetraploid) Seeds to Interactive Effects of Salinity and Temperature

“…Several studies have shown that germination responses are significantly affected by salinity and temperature [28,[46][47][48][49]. Polyploid plants can exhibit higher adaptability, increased vigour and resistance to unfavourable environmental factors compared to their diploid ones [50,51].…”

“…Tetraploid seeds of Italian ryegrass were bigger and heavier than their diploid seeds. Bigger seeds at a high ploidy level have more advantages than smaller seeds at a lower ploidy level [48]. For that matter; tetraploid seeds have more carbon reserves and can generate a lower osmotic potential.…”

Improving abiotic stress tolerance of forage grasses – prospects of using genome editing

“…Thus, there is ample genetic variation still to be exploited within the genetic resources of perennial ryegrass. Induced polyploidization is also widely exploited in forage crop breeding as one of unconventional techniques to develop new superior yielding and abiotic stress tolerant breeding material ( Akinroluyo et al., 2019 ; Akinroluyo et al., 2020 ; Rauf et al., 2021 ).…”

Improving Abiotic Stress Tolerance of Forage Grasses – Prospects of Using Genome Editing

“…Thus, there is ample genetic variation still to be exploited within the genetic resources of perennial ryegrass. Induced polyploidization is also widely exploited in forage crop breeding as one of unconventional techniques to develop new superior yielding and abiotic stress tolerant breeding material [246][247][248].…”