The elite Macadamia cultivar,‘Guire 1’,as experimental material,was treated with selenium fertilizer via foliar spraying at various growth stages.The selenium content and free amino acid composition in macadamia nut...The elite Macadamia cultivar,‘Guire 1’,as experimental material,was treated with selenium fertilizer via foliar spraying at various growth stages.The selenium content and free amino acid composition in macadamia nuts of different selenium fertilizer treatments were measured and analyzed.The findings indicated that foliar application of selenium fertilizer effectively enhanced the accumulation of selenium in the kernels of macadamia nuts.The time of foliar application of selenium fertilizer significantly influenced the effective accumulation of selenium in kernels.Notably,foliar application during the full-bloom stage resulted in significantly higher accumulation than that at other stages.Principal component analysis(PCA)was employed to develop a comprehensive evaluation model for the effective accumulation of selenium in kernels from different treatments.The model indicated that the optimal comprehensive quality of free amino acids was attained when the selenium accumulation in kernels reached 0.223 mg/kg.The reliability and validity of the evaluation model were further corroborated through stepwise regression analysis.This study provided theoretical and practical foundations for improving macadamia quality traits and established a basis for standardizing selenium fertilization protocols.展开更多
Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to...Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses.展开更多
文摘The elite Macadamia cultivar,‘Guire 1’,as experimental material,was treated with selenium fertilizer via foliar spraying at various growth stages.The selenium content and free amino acid composition in macadamia nuts of different selenium fertilizer treatments were measured and analyzed.The findings indicated that foliar application of selenium fertilizer effectively enhanced the accumulation of selenium in the kernels of macadamia nuts.The time of foliar application of selenium fertilizer significantly influenced the effective accumulation of selenium in kernels.Notably,foliar application during the full-bloom stage resulted in significantly higher accumulation than that at other stages.Principal component analysis(PCA)was employed to develop a comprehensive evaluation model for the effective accumulation of selenium in kernels from different treatments.The model indicated that the optimal comprehensive quality of free amino acids was attained when the selenium accumulation in kernels reached 0.223 mg/kg.The reliability and validity of the evaluation model were further corroborated through stepwise regression analysis.This study provided theoretical and practical foundations for improving macadamia quality traits and established a basis for standardizing selenium fertilization protocols.
基金supported by the National Key Research and Development Program of China(2019YFE0197100)the earmarked fund for China Agriculture Research System(CARS-03-01A)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences。
文摘Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses.
