Physiological responses of rice to increased day and night temperatures

Wanju Shi

Research output: Thesisinternal PhD, WU

Abstract

A more rapid increase in night-time temperature compared with day-time temperature and the increased frequency of heat waves associated with climate change present a serious threat to rice (Oryza sativa L.) production and food security. This thesis aims to understand the impact of high night-time temperature (HNT) and high day-time temperature (HDT) on rice grain yield and grain quality and to examine adaptation strategies to cope with high-temperature stresses.

Grain yield and quality of a susceptible indica genotype (Gharib) and all tested hybrids, when exposed to HNT in the field, were significantly reduced across seasons, with less average reduction in the dry season than in the wet season, indicating that other environmental factors under field conditions may contribute to impacts of HNT on yield. Among the different yield components, a reduced number of spikelets m−2 significantly contributed to yield loss under HNT followed by the consistently lower single-grain weight across all genotypes, while the impact of the decrease in percentage seed-set was less and season-specific. Lower grain yield and poorer grain quality in susceptible cultivar Gharib were associated with a significant reduction in non-structural carbohydrate translocation after flowering, resulting in reduced grain-filling duration. Increased total nitrogen application did not alleviate the negative impact of HNT. The proposed model approach showed that there were significant differences among cultivars in their changes in source-sink relationships in response to HNT. Given that rice grain yield and quality are challenged by a rise in HDT and HNT, in particular at flowering and during grain filling, differential impacts of HNT and HDT during these critical stages were observed. For the single-grain growth during grain filling, HDT either independently or in combination with HNT exerted greater influences than HNT on the grain filling dynamics, activities of starch metabolism enzymes, temporal starch accumulation patterns, and the process of chalk formation. During flowering, HDT increased spikelet sterility in tested hybrids and hybrids were less tolerant to high temperatures than high-yielding inbred varieties. Moreover, in contrast with HNT, HDT played a dominant role in determining spikelet fertility. Novel observations with a series of snapshots of dynamic fertilization processes demonstrated that disturbances in the pre-fertilization phase were the primary causes for heat-induced spikelet sterility, indicating the effectiveness of employing the early-morning flowering trait for mitigating the impact of heat stress at flowering on rice.

Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • Wageningen University
Supervisors/Advisors
  • Struik, Paul, Promotor
  • Yin, Xinyou, Co-promotor
  • Jagadisch, K.S.V., Co-promotor, External person
Award date13 Dec 2017
Place of PublicationWageningen
Publisher
Print ISBNs9789463437110
DOIs
Publication statusPublished - 2017

Fingerprint

night temperature
physiological response
rice
temperature
filling period
flowering
inflorescences
grain yield
starch
heat
source-sink relationships
chalk

Keywords

  • crops
  • rice
  • oryza sativa
  • plant physiology
  • temperature
  • crop yield
  • grain
  • agronomy

Cite this

Shi, Wanju. / Physiological responses of rice to increased day and night temperatures. Wageningen : Wageningen University, 2017. 202 p.
@phdthesis{1a7e3582d6f840a9a4fae1cae2ff46cb,
title = "Physiological responses of rice to increased day and night temperatures",
abstract = "A more rapid increase in night-time temperature compared with day-time temperature and the increased frequency of heat waves associated with climate change present a serious threat to rice (Oryza sativa L.) production and food security. This thesis aims to understand the impact of high night-time temperature (HNT) and high day-time temperature (HDT) on rice grain yield and grain quality and to examine adaptation strategies to cope with high-temperature stresses. Grain yield and quality of a susceptible indica genotype (Gharib) and all tested hybrids, when exposed to HNT in the field, were significantly reduced across seasons, with less average reduction in the dry season than in the wet season, indicating that other environmental factors under field conditions may contribute to impacts of HNT on yield. Among the different yield components, a reduced number of spikelets m−2 significantly contributed to yield loss under HNT followed by the consistently lower single-grain weight across all genotypes, while the impact of the decrease in percentage seed-set was less and season-specific. Lower grain yield and poorer grain quality in susceptible cultivar Gharib were associated with a significant reduction in non-structural carbohydrate translocation after flowering, resulting in reduced grain-filling duration. Increased total nitrogen application did not alleviate the negative impact of HNT. The proposed model approach showed that there were significant differences among cultivars in their changes in source-sink relationships in response to HNT. Given that rice grain yield and quality are challenged by a rise in HDT and HNT, in particular at flowering and during grain filling, differential impacts of HNT and HDT during these critical stages were observed. For the single-grain growth during grain filling, HDT either independently or in combination with HNT exerted greater influences than HNT on the grain filling dynamics, activities of starch metabolism enzymes, temporal starch accumulation patterns, and the process of chalk formation. During flowering, HDT increased spikelet sterility in tested hybrids and hybrids were less tolerant to high temperatures than high-yielding inbred varieties. Moreover, in contrast with HNT, HDT played a dominant role in determining spikelet fertility. Novel observations with a series of snapshots of dynamic fertilization processes demonstrated that disturbances in the pre-fertilization phase were the primary causes for heat-induced spikelet sterility, indicating the effectiveness of employing the early-morning flowering trait for mitigating the impact of heat stress at flowering on rice.",
keywords = "crops, rice, oryza sativa, plant physiology, temperature, crop yield, grain, agronomy, gewassen, rijst, oryza sativa, plantenfysiologie, temperatuur, gewasopbrengst, graan, agronomie",
author = "Wanju Shi",
note = "WU thesis 6828 Includes bibliographical references. - With summary in English",
year = "2017",
doi = "10.18174/425491",
language = "English",
isbn = "9789463437110",
publisher = "Wageningen University",
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}

Shi, W 2017, 'Physiological responses of rice to increased day and night temperatures', Doctor of Philosophy, Wageningen University, Wageningen. https://doi.org/10.18174/425491

Physiological responses of rice to increased day and night temperatures. / Shi, Wanju.

Wageningen : Wageningen University, 2017. 202 p.

Research output: Thesisinternal PhD, WU

TY - THES

T1 - Physiological responses of rice to increased day and night temperatures

AU - Shi, Wanju

N1 - WU thesis 6828 Includes bibliographical references. - With summary in English

PY - 2017

Y1 - 2017

N2 - A more rapid increase in night-time temperature compared with day-time temperature and the increased frequency of heat waves associated with climate change present a serious threat to rice (Oryza sativa L.) production and food security. This thesis aims to understand the impact of high night-time temperature (HNT) and high day-time temperature (HDT) on rice grain yield and grain quality and to examine adaptation strategies to cope with high-temperature stresses. Grain yield and quality of a susceptible indica genotype (Gharib) and all tested hybrids, when exposed to HNT in the field, were significantly reduced across seasons, with less average reduction in the dry season than in the wet season, indicating that other environmental factors under field conditions may contribute to impacts of HNT on yield. Among the different yield components, a reduced number of spikelets m−2 significantly contributed to yield loss under HNT followed by the consistently lower single-grain weight across all genotypes, while the impact of the decrease in percentage seed-set was less and season-specific. Lower grain yield and poorer grain quality in susceptible cultivar Gharib were associated with a significant reduction in non-structural carbohydrate translocation after flowering, resulting in reduced grain-filling duration. Increased total nitrogen application did not alleviate the negative impact of HNT. The proposed model approach showed that there were significant differences among cultivars in their changes in source-sink relationships in response to HNT. Given that rice grain yield and quality are challenged by a rise in HDT and HNT, in particular at flowering and during grain filling, differential impacts of HNT and HDT during these critical stages were observed. For the single-grain growth during grain filling, HDT either independently or in combination with HNT exerted greater influences than HNT on the grain filling dynamics, activities of starch metabolism enzymes, temporal starch accumulation patterns, and the process of chalk formation. During flowering, HDT increased spikelet sterility in tested hybrids and hybrids were less tolerant to high temperatures than high-yielding inbred varieties. Moreover, in contrast with HNT, HDT played a dominant role in determining spikelet fertility. Novel observations with a series of snapshots of dynamic fertilization processes demonstrated that disturbances in the pre-fertilization phase were the primary causes for heat-induced spikelet sterility, indicating the effectiveness of employing the early-morning flowering trait for mitigating the impact of heat stress at flowering on rice.

AB - A more rapid increase in night-time temperature compared with day-time temperature and the increased frequency of heat waves associated with climate change present a serious threat to rice (Oryza sativa L.) production and food security. This thesis aims to understand the impact of high night-time temperature (HNT) and high day-time temperature (HDT) on rice grain yield and grain quality and to examine adaptation strategies to cope with high-temperature stresses. Grain yield and quality of a susceptible indica genotype (Gharib) and all tested hybrids, when exposed to HNT in the field, were significantly reduced across seasons, with less average reduction in the dry season than in the wet season, indicating that other environmental factors under field conditions may contribute to impacts of HNT on yield. Among the different yield components, a reduced number of spikelets m−2 significantly contributed to yield loss under HNT followed by the consistently lower single-grain weight across all genotypes, while the impact of the decrease in percentage seed-set was less and season-specific. Lower grain yield and poorer grain quality in susceptible cultivar Gharib were associated with a significant reduction in non-structural carbohydrate translocation after flowering, resulting in reduced grain-filling duration. Increased total nitrogen application did not alleviate the negative impact of HNT. The proposed model approach showed that there were significant differences among cultivars in their changes in source-sink relationships in response to HNT. Given that rice grain yield and quality are challenged by a rise in HDT and HNT, in particular at flowering and during grain filling, differential impacts of HNT and HDT during these critical stages were observed. For the single-grain growth during grain filling, HDT either independently or in combination with HNT exerted greater influences than HNT on the grain filling dynamics, activities of starch metabolism enzymes, temporal starch accumulation patterns, and the process of chalk formation. During flowering, HDT increased spikelet sterility in tested hybrids and hybrids were less tolerant to high temperatures than high-yielding inbred varieties. Moreover, in contrast with HNT, HDT played a dominant role in determining spikelet fertility. Novel observations with a series of snapshots of dynamic fertilization processes demonstrated that disturbances in the pre-fertilization phase were the primary causes for heat-induced spikelet sterility, indicating the effectiveness of employing the early-morning flowering trait for mitigating the impact of heat stress at flowering on rice.

KW - crops

KW - rice

KW - oryza sativa

KW - plant physiology

KW - temperature

KW - crop yield

KW - grain

KW - agronomy

KW - gewassen

KW - rijst

KW - oryza sativa

KW - plantenfysiologie

KW - temperatuur

KW - gewasopbrengst

KW - graan

KW - agronomie

U2 - 10.18174/425491

DO - 10.18174/425491

M3 - internal PhD, WU

SN - 9789463437110

PB - Wageningen University

CY - Wageningen

ER -