Identification of drought stress tolerance in wild species germplasm of rice based on leaf and root morphology

Abstract

Drought is the major abiotic constraint to the rice production in the rain-fed areas across Asia and sub-Saharan Africa. Wild species of Oryza offer a wide spectrum of adaptive traits and can serve as potential donors of biotic and abiotic stress tolerance. At the Punjab Agricultural University, we are maintaining an active collection of 1630 accessions of wild species germplasm (AA, CC, BBCC and CCDD) of rice. These accessions were screened to assess genetic variation for drought tolerance under field conditions. Severe water stress was imposed at the late vegetative stage by withholding water initially for 25 d and then extended further to 35 d during kharif season in the years 2013–14 and 2015–16. The tolerance score for drought stress was based on the extent of leaf rolling and leaf drying. Based on the 2 years’ data, seven accessions from Oryza rufipogon, four from Oryza longistaminata and one each from Oryza officinalis and Oryza latifolia were found tolerant to drought stress. These selected accessions were further phenotype for root morphology. The average root length among the selected accessions ranges between 36 and 80 cm and the number of primary roots vary from 30 to 87 cm. The O. rufipogon accession IRGC 106433, O. longistaminata accession IRGC 92656A, O. officinalis accession IRGC 101152 and O. latifolia accession IRGC 80769 showed approximately 2–2.5 times longer root length and number than the indica rice elite cultivar PR121. The results indicated potentiality of selected wild species germplasm for conferring drought tolerance to the elite cultivars.

Identification of Factors Linked to Higher Water-Deficit Stress Tolerance in Amaranthus hypochondriacus Compared to Other Grain Amaranths and A. hybridus, Their Shared Ancestor

“…Thus, the understanding of the drought tolerance mechanism(s) that operate in grain amaranth remains limited. Natural variations in WDS tolerance are common in plants, as established by copious information describing differences between natural accessions, wild populations and domesticated C3 plants, including rice [16,17,18], C3 and C4 grasses [19], different C4 subtypes [20,21], or contrasting genotypes of commercially important C3 and C4 crops [5,22,23]. Based on this evidence, and considering their different geographic origin and preferential adaptation to temperate or tropical conditions, it was hypothesized that WDS tolerance in grain amaranths and A. hybridus , their shared ancestor, would vary significantly between species.…”

Multi-Omics-Based Identification and Functional Characterization of Gh_A06G1257 Proves Its Potential Role in Drought Stress Tolerance in Gossypium hirsutum

“…Narrow genetic diversity among crops, including wild wheat, leads the cultivated species to lose tolerance to drought (Budak et al, 2013 ). Similarly, wild species of rice offer an extensive range of adaptive traits and can serve as potential contributors of biotic and abiotic stress tolerance (Neelam et al, 2018 ). In the current study, MG85 was used, which has a higher tolerance to drought and salt stresses than CRI12 (Xu et al, 2020 ) while LT40 is highly vulnerable to both the aforementioned stresses (Yang et al, 2019 ).…”

Screening of tarragon accessions based on physiological and phytochemical responses under water deficit

“…Wild germplasms and native genotypes are valuable genetic resources for crucial physiological traits such as drought tolerance which could be identified and applied in breeding programs 6 . Obviously, among the different populations of a plant species, those that are more tolerant to water stress are better choices for arid and semi-arid areas 7 . The impact of water scarcity on plant yields and adverse changes of active substances of medicinal plants must be thoroughly evaluated.…”