水氮耦合对金线莲生长和品质的影响

Effect of water and nitrogen coupling on growth and quality of Anoectochilus roxburghii

【目的】探究不同水氮耦合处理对金线莲生长和品质的影响,为确定金线莲栽培的适宜水氮耦合方案提供参考。【方法】以大叶金线莲为试材,采取裂区设计,设置3种施氮量(N1:3.3 g/m^(2);N2:6.6 g/m^(2);N3:9.9 g/m^(2))和4种灌水量(W1:(45±5)%θ_(f);W2:(55±5)%θ_(f);W3:(65±5)%θ_(f);W4:(75±5)%θ_(f);其中θ_(f)为田间持水量)组合处理,以不施肥、不灌溉为对照(CK),栽培5个月后,测定13个处理金线莲的生长指标(保存率、株高、单株叶片数、叶长和叶宽、茎节数、节长、根长、根数、单株鲜质量及干质量、折干率)、生理指标(总叶绿素、可溶性蛋白、可溶性糖含量和过氧化物酶、超氧化物歧化酶活性)和品质指标(总黄酮含量及总多糖、金线莲苷、总生物碱和总氨基酸质量分数),分析灌水量和施氮量对金线莲生长及活性成分的影响。【结果】(1)与CK相比,除N1W1、N3W1处理外,其余处理均可以提高金线莲单株鲜质量、干质量、折干率、茎节数、节长和株高,其中N2W3处理金线莲的单株鲜质量、茎节数、节长、株高均达最大值,较CK分别提高了35.67%,33.18%,16.14%和35.45%。在30~60 d的较短栽培时期内,金线莲栽培的保存率在各处理之间差异不明显,但随着栽培时间延长,N1、N2条件下的水氮耦合优势逐渐显现。与CK相比,各处理金线莲的单株叶片数、叶长、叶宽、根长和根数无显著差异。(2)与CK相比,除N2W1处理外,其余处理均可以提高金线莲可溶性糖含量、SOD活性和总叶绿素含量;除N1W4和N3W4处理外,其余处理均可以降低金线莲的POD活性。与CK相比,各处理对金线莲可溶性蛋白含量有显著影响,同一施氮水平下,W1条件下的可溶性蛋白含量显著高于其他处理。(3)与CK相比,各处理对金线莲总氨基酸和总多糖质量分数均有显著影响,其中N2W3处理的总氨基酸质量分数最高,为9.18%;N1W3处理的总多糖质量分数最高,为45.08%。在W2、W3条件下,金线莲的总黄酮含量和金线莲苷质量分数随施氮量的增加均呈先增后减趋势,施氮效果均表现为N2>N3>N1,且均以N2W3处理最高,分别为25.04 mg/g和19.36%。(4)熵权系数法分析结果显示,12种肥水组合中,耦合作用效果排名前5的处理为N2W3>N2W2>N3W1>N2W4>N3W2。【结论】适宜的水氮耦合处理有利于金线莲生长及活性成分的积累,金线莲较优的肥水组合是灌水量为田间持水量的60%~70%,施氮量为6.6 g/m^(2)。

【Objective】This study investigated the effects of different water and nitrogen coupling treatments on growth and quality of Anoectochilus roxburghii to provide references for determining appropriate water and nitrogen coupling scheme for A.roxburghii.【Method】A split-zone design was adopted for Daye A.roxburghii with three nitrogen application rates of N13.3 g/m^(2),N26.6 g/m and N39.9 g/m^(2) and four irrigation rates of W1(45±5)%θ_(f),W2(55±5)%θ_(f),W3(65±5)%θ_(f) and W4(75±5)%θ_(f)(θ_(f) is the amount of water held in the field).The case with no fertilizer and no irrigation was used as the control(CK).After cultivation for 5 months,growth indexes(preservation rate,plant height,number of leaf per plant,leaf length and leaf width,number of stems,stems length,number of roots,root length,fresh weight per plant and dry weight and discount rate),physiological parameters(soluble protein,soluble su-gar,total chlorophyll content,SOD activity and POD activity)and quality indicators(total flavonoids,kinsenoside,total alkaloids,total amino acid and total polysaccharide)were determined.Then,the effects of irrigation water and nitrogen application on growth and active components of A.roxburghii were analyzed.【Result】①Compared with CK,all treatments except N1W1 and N3W1 increased fresh weight per plant,dry weight,discount rate,number of stems,stems length and plant height of A.roxburghii.The N2W3 treatment had the highest fresh weight per plant,number of stems,stems length and plant height,and they were 35.67%,33.18%,16.14%and 35.45%higher than that of CK.During the short cultivation period of 30-60 d,the differences in preservation of A.roxburghii cultivation were not significant among treatments,while the advantages of water and nitrogen coupling under N1 and N2 conditions gradually appeared as the cultivation period prolonged.Compared with CK,there were no significant differences in number of leaf per plant,leaf length and leaf width,number of root and root length among treatments.②Compared with CK,all treatments except N2W1 increased soluble sugar,SOD activity and total chlorophyll content,while decreased POD activity except for N1W4 and N3W4 treatments.All treatments had significant effects on soluble protein content,and that under W1 conditions was significantly higher than other treatments at same nitrogen levels.③Compared with CK,all treatments had significant effects on total amino acid and total polysaccharide mass fraction of Clematis chinensis.The total amino acid mass fraction treated with N2W3 was the highest,at 9.18%.And the total polysaccharide mass fraction treated with N2W3 was the highest,at 45.08%.The total flavonoids and kinsenoside of A.roxburghii under W2 and W3 conditions showed a trend of increasing first and then decreasing with the increase of nitrogen application.The effects of nitrogen application were in the order of N2>N3>N1.The N2W3 treatment had the highest values of 25.04 mg/g and 19.36%,respectively.④The entropy coefficient analysis showed that the top 5 out of the 12 fertilizer combinations were in the order of N2W3>N2W2>N3W1>N2W4>N3W2.【Conclusion】Suitable water and nitrogen coupling treatment was beneficial to the growth of A.roxburghii and accumulation of active ingredients.The preferred fertilizer-water combination for A.roxburghii was irrigation rate of 60%-70%of water holding capacity in field and nitrogen application rate of 6.6 g/m^(2).