施钙量对不同花生荚果发育时期光合碳在植株-土壤系统分配的影响

Effects of calcium application on the distribution of photosynthetic carbon in plant-soil system at different peanut pod development stages

探究施钙对不同花生荚果发育时期光合碳在植株-土壤系统分配的影响,有利于改善钙肥管理,提升花生产量和土壤有机碳含量。本研究选用普通大花生品种‘花育22’,设置CaO 0、75、150和300 kg hm^(-2)4个施钙梯度,分别记为T0、T1、T2、T3,于盆栽条件下研究施钙量对花生产量和不同荚果发育时期光合碳在花生植株-土壤系统中分配的影响。结果表明,不同施钙量对花生植株总干物质积累无明显影响。适宜施钙量可显著降低花生千克果数和千克仁数,提升花生出仁率、饱果率和荚果产量,在2018年和2019年,T2处理荚果产量较T0可分别提升17.5%和25.1%。基于施钙量与花生荚果和籽仁产量的拟合分析发现,当钙肥施用量为165 kg hm^(-2)和173 kg hm^(-2)时,可分别获得最高的花生荚果和籽仁产量。适宜施钙量可明显提升鸡咀幼果期和荚果膨大期花生植株光合^(13)C的积累量,提升各荚果发育时期^(13)C在花生籽仁中的分配比例,其中,在荚果定型期和籽仁充实期,T2和T3处理下^(13)C在花生籽仁中的分配比例分别可达33.4%~37.2%和38.7%~40.0%。适宜施钙量还可提高花生植株光合^(13)C在土壤中的分配比例,最高可达52.6%(T2),但随着花生荚果发育进程的推进,此分配比例逐渐降低。综上,适宜施钙量可调控不同花生荚果发育时期光合^(13)C在植株-土壤系统的分配,显著提升花生产量和光合^(13)C在花生籽仁和土壤中的分配比例;本研究条件下,推荐适宜施钙量(CaO)为173 kg hm^(-2)。

Investigating the effects of calcium application on the distribution of photosynthetic carbon in the plant-soil system at different stages of the development of peanut pods will help improve the management of calcium fertilizer,and increase the yield of peanut,and the concentration of soil organic carbon.In this study,the common large peanut variety‘Huayu 22’was selected,and four gradients of calcium were applied.They included CaO 0 kg hm^(-2),75 kg hm^(-2),150 kg hm^(-2),and 300 kg hm^(-2),and were designated T0,T1,T2,and T3,respectively.These treatments were established to explore the effects of calcium application on peanut yield and the distribution of photosynthetic carbon in the plant-soil system at different stages of peanut pod development.The results showed that the total dry matter accumulation of peanut plants was not affected by the application of different amounts of calcium.The application of a suitable amount of calcium significantly reduced the number of peanut fruit and kernel per kilogram,increased the kernel percent,full pod percent and pod yield,and in 2018 and 2019,the T2 treatment increased the pod yield by 17.5%and 25.1%compared with T0,respectively.A fitting analysis of the calcium applied with the peanut pod and kernel yield revealed that the highest peanut pod and kernel yield could be obtained when the calcium applications were 165 kg hm^(-2)and 173 kg hm^(-2),respectively.The application of a suitable amount of calcium significantly increased the photosynthetic^(13)C accumu-lation in peanut plants at the young fruit and pod bulking stages,increased the proportion of^(13)C in peanut kernels at different pod development and the pod setting and kernel filling stages.The proportion of^(13)C in the peanut kernels under the T2 and T3 treatments was 33.4%-37.2%and 38.7%-40.0%,respectively.The proportion of^(13)C in the soil also increased when a suitable amount of calcium was applied.The increase was as high as 52.6%(T2),but with the development in peanut pods,the proportion of^(13)C in soil decreased gradually.In conclusion,the application of an appropriate amount of calcium can regulate the distribution of photosynthetic^(13)C in the plant-soil system at different pod development stages of peanut and significantly improved the peanut yield and proportion of photosynthetic^(13)C in peanut kernel and soil.Under the conditions of this study,the recommended amount of calcium to apply was 173 kg hm^(-2).