东京四照花嫩枝扦插繁殖及生根过程中生理指标的动态变化

Cutting propagation of softwood and dynamic changes in physiological indicators during the rooting process of Cornus hongdongensis subsp. tonkinensis

【目的】研究植物生长调节剂、扦插基质和生长阶段对东京四照花Cornus hongkongensis subsp.tonkinensis嫩枝扦插生根过程中的形态特征和生理生化特性,为东京四照花的繁殖和生产提供科学依据。【方法】以清水处理为对照,对植物生长调节剂种类[生根粉1号(ABT-1)、萘乙酸(NAA)和吲哚乙酸(IAA)]、质量浓度(100、300和500 mg·L^(−1))和浸泡时间(30、60和180 min)进行正交设计,采用4种扦插基质[蛭石(S1)、河沙(S2)、V(泥炭土)∶V(蛭石)∶V(珍珠岩)=2∶2∶1(S3)和V(泥炭土)∶V(黄土)=1∶1(S4)],在不同生长阶段(初期、中期和末期)进行嫩枝扦插,统计分析各生根指标,测定生根过程中营养物质质量分数和相关生根酶活性的变化。【结果】①东京四照花插穗生根类型以皮部生根为主,占总生根数的58.60%。②在正交试验中,300 mg·L^(−1)IAA浸泡30 min处理生根率最高(77.78%)。③在扦插基质中,S3基质中插穗生根率和生根指数均最高(82.22%和19.34)。④在生长阶段试验中,生长中期插穗生根率最高(82.22%)。⑤相较于对照,IAA处理有效促进了插穗体内的养分消耗,提高了氧化酶的活性。⑥相关分析表明:生根率与根原基诱导和愈伤形成期间内的可溶性糖、淀粉和可溶性蛋白呈显著负相关(P<0.05),与过氧化物酶(POD)和超氧化物歧化酶(SOD)呈极显著正相关(P<0.01)。【结论】在生长中期采制的穗条通过300 mg·L^(−1)IAA浸泡30 min,扦插在S3基质中,生根率和生根指数均最高,分别可达82.22%和19.34。

[Objective]This study,with an investigation of the effects of plant growth regulator soaking,substrate type and growth stage of cutting scion on rooting of Cornus hongdongensis subsp.tonkinensis as well as the morphological characteristics and physiological and biochemical properties of cutting during the rooting process,is aimed to establish a scientific basis for its propagation and production.[Method]First,using clear water treatment as a control,an orthogonal design was performed for plant growth regulator treatment,including types(ABT-1,NAA and IAA),concentrations(100,300 and 500 mg·L^(−1))and soaking duration(30,60 and 180 min);then, 4 types of cutting substrates were prepared, containing vermiculite (S1), river sand (S2), V(peat soil)∶V(vermiculite)∶V(perlite)=2∶2∶1(S3) and V(peat soil)∶V(loess)=1∶1(S4);afterwards, cutting scions were collected at three stages on July 12, August 15 and September 1, respectively before the rooting index was statistically analyzed, and the changes of nutrient content and rooting-related enzyme activities in the process of rooting were measured. [Result] (1) The rooting type was dominated by skin rooting, which accounted for 58.60% of the total number of roots. (2) In the orthogonal test, the hightest rooting rate of 77.78% was achieved by soaking the cutting with 300 mg·L^(−1) IAA for 30 min. (3) In the cutting substrate test, the highest rooting rate and rooting index were found in S3 substrate treatment (82.22% and 19.34). (4) In growth stage test, mid- growth cutting rooting was highest (82.88%). (5) Compared with the control treatment, the IAA treatment effectively promoted nutrient consumption in the cutting and increased the activity of oxidative enzymes. (6) Correlation analysis showed that rooting rate was significantly negatively correlated with soluble sugars, starch and soluble proteins during the period of root primordium induction and healing formation (P<0.05), and highly significantly positively correlated with POD and SOD (P<0.01). [Conclusion] Cutting scion taken at mid-growth through 300 mg·L^(−1)IAA for 30 min treatment and embed in S3 substrate achieved the highest rooting percentage and rooting index up to 82.22% and 19.34, respectively.