Chilling tolerance in Zizania latifólia

Abstract

The tumescent stems of Zizania latifolia are consumed as vegetable in southern and eastern Asia. This study aimed to compare photosynthesis and chilling tolerance parameters between two well-known Zizania latifolia cultivars: Longjiao 2 and Zhejiao 911, which are chilling tolerant and sensitive, respectively. We found that severe cold stress induced photosynthesis inhibition (5°C) resulted from non-stomatal factors. However, net photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of the cultivar Longjiao 2 were higher than that of Zhejiao 911 with more gradual variations. Six parameters of chlorophyll fluorescence including latent activity of PSII (Fv/F0), efficiency of primary photochemistry (Fv/ Fm), photochemical quenching coefficient (qP), non-photochemical quenching coefficient (qN), quantum yield of electric transport (Yield) and the ratio of electric transport at PSII (ETR) were analyzed in the two cultivars. We found that Longjiao 2 had significantly higher Fv/Fm and qN than Zhejiao 911 while qP values were only slightly different for the two lines at severe cold stress. In our experiments, Yield and ETR changed in a similar way in both Longjiao 2 and Zhejiao 911. In addition, the ability of heat dissipation of Longjiao 2 was statistically higher than that found in Zhejiao 911 when treated at 5°C for one day. These data suggest that cultivar Longjiao 2 induces chilling tolerance by modulating critical pathways including photosynthesis and energy dissipation.

Domestication, breeding, omics research, and important genes of Zizania latifolia and Zizania palustris

“…Due to its high nutritional value, developing germplasms resistant to seed shattering remains a top priority in the domestication and breeding of Z. latifolia ( Xie et al., 2022 ). As a graminaceous crop closely related to rice, Z. latifolia boasts myriad beneficial traits that rice lacks, including rice blast resistance, thick stalks, strong tillering, low-temperature resistance, flood resistance, rapid grouting maturity, high biological yields, and optimizing protein and lysine contents in seeds ( Chen et al., 2012 ; Ye et al., 2016 ; Yan et al., 2022 ). Hence, it is capable of overcoming the narrow bottleneck of genetic resources for rice breeding and providing important materials for optimizing genetic traits.…”