以 6 年生‘烟富 3’/SH6/平邑甜茶为试材,利用^ 15N 同位素标记,研究 LP+NU(2015 年落叶前摘叶+2016 年萌芽前枝干不喷施尿素)、LP+U(2015 年落叶前摘叶+2016 年萌芽前枝干喷施尿素)、NLP+NU(2015 年落叶前不摘叶+2016 年萌芽前枝干不喷施尿素)、NLP+U(2015 年落叶前不摘叶+2016 年萌芽前枝干喷施尿素)处理对苹果春季土施^15N-尿素吸收、分配及利用特性的影响。结果表明:不同处理苹果根部贮藏营养水平差异显著,其中 NLP+U处理苹果根系淀粉、可溶性总糖、蛋白质、游离氨基酸含量分别为 39.71 mg/g、11.28 mg/g、25.74 mg/g、0.31 mg/g,高于 LP+NU、LP+U、NLP+NU 处理;NLP+U(2015 年不摘叶+2016 年枝干喷施尿素)处理对苹果根系生长促进作用显著,其根长、根表面积、根尖数、表面积密度、根长密度等根系形态指标及根系生物量由高到低分别为 NLP+U>NLP+NU>LP+U>LP+NU 处理,且新梢旺长期苹果植株体内全氮含量由高到低顺序为 NLP+U>NLP+NU>LP+U>LP+NU;不同处理间苹果各器官 Ndff 值存在明显差异,且均以根的 Ndff 最高,各器官的 Ndff 值均以 NLP+U 处理最高,LP+NU 处理最低。NLP+U 处理显著提高了苹果植株氮素利用率。
Six-year-old ‘Yanfu3’/SH6/Malus hupehensis Rehd. and ^15N trace technique were used to explore the effects of LP+NU (leaves were removed before defoliation in 2015, and no urea was sprayed on stems before 2016), LP+U(leaves were removed before defoliation in 2015, spraying urea in stems before 2016), NLP+NU(In 2015, leaves were not picked before defoliation, and no urea was sprayed on stems before 2016), NLP+U (Leaves were not picked before 2015, and urea was sprayed on branches before germination in 2016) on ^15N-urea absorption, utilization and loss of Fuji apple. The main results were as follow: The nutrition level of Apple roots was significantly different under different treatments, The contents of starch, total soluble sugar, protein and free amino acid in Apple roots under NLP+U treatment were 39.71 mg/g, 11.28 mg/g, 25.74 mg/g and 0.31 mg/g respectively, higher than those of LP+NU, LP+U and NLP+NU treatments;The effects of NLP+U (Leaves were not picked before 2015, and urea was sprayed on branches before germination in 2016) treatment on apple root growth was significant,root length, root surface area, root tip number, surface area density, root length density and other root morphological indexes and root biomass from high to low were NLP+U > NLP+NU > LP+U > LP+NU treatment the order of total nitrogen content in new shoot growing from high to low was NLP+U > NLP+NU > LP+U > LP+NU, the Ndff values of apple organs in different treatments were significantly different, and the Ndff of roots was the highest, the Ndff values of all organs were the highest in NLP+U treatment, and lowest in LP+NU treatment. At the same time, NLP+U treatment significantly increased the nitrogen use efficiency of apple plants.
Journal of Shandong Agricultural University (Natural Science Edition )
leaf picking and branch spraying