Exogenous Silicon Alleviates Spikelet Fertility Reduction of Hybrid Rice Induced by High Temperature under Field Conditions
Year: 2014
Type: article
Abstract: Effects of exogenous silicon on spikelet fertility of hybrid rice were investigated at natural high and normal temperatures during anthesis under field conditions with two hybrids,high-temperature sensitive Jinyou 63and high- temperature tolerant Shanyou 63as material.The exogenous silicon via fertilizer application,in the form of sodium silicon(Na2 SiO3 ·9H2 O),was consecutively spayed for three times at jointing stage at four concentrations,0mmol/L(T-CK),1.25mmol/L(T-1.25),2.50mmol/L(T-2.50),and 3.75mmol/L(T-3.75).Varietal responses in terms of pollination properties,anther dehiscence and spikelet pollination rate were examined to establish a feasible screening scheme of the most appropriate sodium silicate application level in rice management practices.Results showed that, sodium silicate applications at the concentration of 1.25 mmol/L,2.50 mmol/L or 3.75 mmol/L under high temperature in field environments effectively increased the germinated pollen number per stigma by 16.9%and 39.6% for the heat-sensitive Jinyou 63and heat-tolerant Shanyou 63,respectively.The number of pollen grains per stigma increased by 3.4% and 30.5%,respectively.The pollen germination rate rose by 11.3and 7.0percentage points, respectively;the percentage of florets with more than 10germinated pollen grains was increased by 9.3and 27.6 percentage points,respectively;while the percentage of florets with fewer than 20pollen grains was reduced by 18.8 and 8.1percentage points,respectively.Application of the silicon fertilizer also increased anther basal dehiscence width by relative values of 19.0%and 10.3%,respectively,while it improved spikelet pollination rate by absolute values of 10.6and 4.7percentage points in the sensitive and tolerant hybrids,respectively.These results showed that the effect of silicon in alleviating fertility reduction may be mainly attributed to the pollen quality improvement,but not the pollen quantity or the anther dehiscence.Exogenous silicon was more effective for high-temperature sensitive combination than that for the tolerant and the most effective dosage was at the concentration of 2.50mmol/L.
Source: Zhongguo shuidao kexue
Author: WU Chen-yan
Institution: Yangtze University
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W2363469302