嫁接与施氮对甜瓜产量和氮素吸收、利用的影响

Effects of grafting and nitrogen fertilization on melon yield and nitrogen uptake and utilization

通过裂区设计田间试验,主区为2种栽培方式(嫁接栽培和自根栽培),副区为4个施氮水平(0、120、240、360 kg N·hm^(-2)),研究了栽培方式和施氮量对甜瓜产量和品质、氮素运移和分配,以及氮素利用率的影响.结果表明:嫁接栽培的甜瓜商品瓜产量较自根甜瓜提高了7.3%,可溶性固形物含量降低了0.16%~3.28%;生长前期嫁接栽培甜瓜氮素累积量较自根栽培低,结果后嫁接栽培氮素累积量显著升高,收获时植株氮素累积量较自根栽培增加了5.2%,果实中的氮素累积量提高了10.3%;嫁接栽培植株氮素向果实的转移量较自根栽培提高了20.9%,嫁接栽培果实中的氮素分配率在80%以上,自根栽培的分配率在80%以下;在同一施氮水平下,嫁接栽培的甜瓜氮素吸收利用率较自根栽培提高了1.3%~4.2%,氮素农学效率提高了2.73~5.56 kg·kg^(-1),氮素生理利用率提高了7.39~16.18 kg·kg^(-1);从商品瓜产量、氮素吸收量和氮素利用率综合考虑,施氮量240 kg·hm^(-2)为本区域嫁接甜瓜较适宜的氮素用量.

A split-field design experiment was carried out using two main methods of cultivation （ grafting and self-rooted cultivation） and subplots with different nitrogen application levels （0, 120, 240, and 360 kg N · hm-2 ） to investigate the effects of cultivation method and nitrogen appli- cation levels on the yield and quality of melons, nitrogen transfer, nitrogen distribution, and nitro- gen utilization rate. The results showed that melons produced by grafting cultivation had a 7.3% in- crease in yield and a 0.16%-3.28% decrease in soluble solid content, compared to those produced by self-rooted cultivation. The amount of nitrogen accumulated in melons grafted in the early growth phase was lower than that in self-rooted melons, and higher after fruiting. During harvest, nitrogen accumulation amount in grafted melon plants was 5.2% higher than that in self-rooted plants and ni- trogen accumulation amount in fruits was 10.3% higher. G nitrogen transfer from plants to fruits by 20.9% compared bution in fruits was 〉80% in grafted rafting cultivation increased the amount of to self-rooted cultivation. Nitrogen distri- melons, whereas that in self-rooted melons was 〈80%. Under the same level of nitrogen fertilization, melons cultivated by grafting showed 1.3%-4.2% increase in nitrogen absorption and utilization rate, 2.73-5.56 kg· kg-1 increase in nitrogen agronomic effi- ciency, and 7.39-16.18 kg · kg-1 increase in nitrogen physiological efficiency, compared to self- rooted cultivation. On the basis of the combined perspective of commercial melon yield, and nitro- gen absorption and utilization rate, an applied nitrogen amount of 240 kg · hm-2 is most suitable for graf-ting cultivation in this region.