Translocation efficiencies and allocation of nitrogen, phosphorous and potassium in rice as affected by silicon fertilizer under high daytime temperature

Abstract

High temperature has become a bottleneck limiting rice production in many rice‐growing districts. Silicon is considered as a beneficial element for rice development, being involved in mitigating adversity stress. In order to ascertain how high temperature and silicon affect nitrogen (N), phosphorous (P) and potassium (K) translocation efficiencies and allocation in rice plants, a field experiment with split plot design was conducted in two consecutive years. Silicon fertilizer treatments, including applying silicon fertilizer and without applying silicon fertilizer, were regarded as main plots. Temperature treatments, including high daytime temperature (HDT) and normal temperature (NT), were assigned as subplots. The results indicated that, as compared to NT, HDT reduced the translocation efficiencies of N, P and K in leaves and stems plus sheaths except for the K translocation efficiency in stems plus sheaths. Moreover, HDT decreased grain yield and the allocation rates of N, P and K in panicles at maturity. Under HDT, the application of silicon fertilizer obviously enhanced the N translocation efficiency of leaves and stems plus sheaths, and the K translocation efficiency of leaves. The application of silicon fertilizer increased grain yield and the allocation rates of N and K in panicles at maturity under HDT. Correlation analysis showed that rice grain yield was positively significantly correlated with N, P and K translocation efficiencies of leaves and their allocation rates in panicles at maturity. Conversely, grain yield was negatively related to the N and P allocation rates in leaves and stems plus sheaths at maturity. These results imply that HDT generated adverse effect on the translocation efficiency of nutrition in rice plants, which might be another damage induced by high temperature to the formation of rice grain yield. Additionally, silicon fertilizer could play a key role in positively regulating the N and K translocation efficiencies and allocation rates in rice under HDT.

Inter‐annual climate variability constrains rice genetic improvement in China

“…Moreover, increase in night respiration was also related to the decrease in spikelet number per panicle and grain yield at high night temperature (Xu et al, 2021). Only a few studies have investigated the effects of high temperature on N absorption and utilization in rice (Ito et al, 2009;Kanno et al, 2009;Liu et al, 2019). Generally, high temperature did not affect total aboveground N accumulation at maturity, but decreased the translocation and allocation of nitrogen to panicle, which led to lower grain N concentration (Ito et al, 2009;Liu et al, 2019).…”

“…Only a few studies have investigated the effects of high temperature on N absorption and utilization in rice (Ito et al, 2009;Kanno et al, 2009;Liu et al, 2019). Generally, high temperature did not affect total aboveground N accumulation at maturity, but decreased the translocation and allocation of nitrogen to panicle, which led to lower grain N concentration (Ito et al, 2009;Liu et al, 2019). Since translocation of non-structural carbohydrates to grain is significantly reduced at high night temperature (Shi et al, 2013), it is obscure whether low grain filling percentage at high night temperature is also related to the reduction in N translocation to grain.…”

Foliar Brassinolide Sprays Ameliorate Post-Silking Heat Stress on the Accumulation and Remobilization of Biomass and Nitrogen in Fresh Waxy Maize

“…This is mainly because BR application improved the grain biomass accumulation, resulting in a dilutive effect. In rice, silicon application does not affect the NC in the stem and panicles but reduces the leaf NC at maturity under AT, whereas silicon application under HS reduces leaf NC and increases stem and panicle NC [44].…”

“…With BR application, the remobilization amount and rate of pre-silking biomass and nitrogen in the stem were increased by HS in both hybrids. In rice, nitrogen remobilization efficiency in the stem and leaf is reduced by HS [44]. In wheat, the nitrogen remobilization is inhibited, whereas biomass remobilization is increased by post-anthesis HS [45].…”

“…A study on rice observed that ear NC was unaffected by HS, whereas the NC in the stem, leaf, and root was increased [39]. However, another study reported that rice leaf NC was unaffected by HS, but stem and grain NC were reduced at maturity [44]. An increase of 2 • C improves the grain and shoot NC in rice [34].…”