LU500614B1 - Method for Cutting Propagation of Tea Seedlings by Inoculating Mixed Arbuscular Mycorrhiza (AM) Fungi - Google Patents

Abstract

A method for cutting propagation of tea seedlings by inoculating mixed arbuscular mycorrhiza (AM) fungi strains. According to a traditional tea seedling cutting propagation method, efficient AM fungi mixed inocula were spread on seedbeds, and were covered with subsoil for cutting planting, and plant hormones were sprayed in 70-90 days after planting to promote symbiosis between the tea seedlings and AM fungi. The method increases the infection rate of the AM fungi to cuttings, thereby enhancing the mycorrhizal propagation effect, and increasing the survival rate, germination rate and callus formation rate of the tea seedlings. Besides, the method can also improve the growth performance such as plant height and root length of the tea seedlings, improve the propagation quality of the tea seedlings, and produce high-quality mycorrhizal tea seedlings. The method has high operability and is suitable for universal popularization.

Description

DESCRIPTION LU500614 Method for Cutting Propagation of Tea Seedlings by Inoculating Mixed Arbuscular Mycorrhiza (AM) Fungi

TECHNICAL FIELD The present invention relates to the technical field of tea seedling propagation, in particular to a method for cutting propagation of tea seedlings by inoculating mixed arbuscular mycorrhizal (AM) fungi.

BACKGROUND Camellia Sinensis (L.) O.Kuntze, belonging to Camellia of Theaceae, is native to southwest China and is one of the important economic crops in China. Cutting propagation, a main propagation method of domestic tea seedlings, has the advantages of retaining the excellent characters of maternal scionss, facilitating standardized production and management of tea gardens and the like. However, the method also has defects of low survival rate, slow growth, low rooting rate, poor adaptability after transplanting and the like. In order to improve quality of cutting propagation seedlings and produce high-quality tea seedlings, inoculation of AM fungi for mycorrhizal cutting propagation have been researched and tested extensively.

For example, Wang et al. (Influence of Arbuscular Mycorrhiza (AM) on Growth of Asexually Propagated Tea Seedlings and Quality of Tea. Journal of Integrative Plant Biology. 2002, 19 (4): 462-468) disclosed pot experiments which carried out in a greenhouse, where AM fungi, Acaulospora Lavis (strain number: 34), Glomus Manihot (strain number: 38) and Glomus Caledonium (strain number: 90036) were inoculated respectively, and influence of AM on growth of the tea seedlings propagated by cuttings and quality of tea were observed. The results showed that inoculation of AM fungi significantly promoted the growth of asexually propagated tea seedlings, with the plant height, dry weight above ground and underground higher than those without inoculation. The difference was extremely significant. AM fungi can obviously promote absorption of inorganic elements (especially P, Ca, Mg and the like) by tea trees. The number of rhizosphere bacteria and actinomycetes and activity of acid phosphatase of the tea seedlings inoculated with the AM fungi were significantly higher than those of CK. Furthermore, by inoculation with the AM fungi, the concentration of tea water extract, amino acids, caffeine and tea polyphenols was also increased, and the quality of tea is improved. However, the research mainly focused on AM inoculation to the tea seedlings after cutting rooting, that is, the growth promotion of tea seedlings with roots, while the growth promotion effect of LUS00614 cuttings in the rootless period was not reflected in this study. In the process of tea cutting propagation, whether the cuttings can take root is directly related to the survival rate of the cuttings and the subsequent growth quality.

Another example 1s the application method of AM fungi in large-scale tobacco cultivation (patent number of 201310085299.0). Initial AM fungal inocula were inoculated and propagated separately, and the spore density of an AM propagule after propagation of each strain was more than 30/g dry soil. Tobacco was co-inoculated with AM fungi inocula by floating seedling culture method to obtain mycorrhizal tobacco seedlings, and the mycorrhizal tobacco seedlings were directly applied to field production, and were inoculated for the second time when transplanted. Clearly, in this study, the seeds were inoculated with fungi in the seed germination stage to germinate and root and realize fungi infection of roots, and then, secondary supplementary inoculation was conducted on the tobacco seedlings with roots, so as to achieve the purposes of promoting rooting and growth. However, the growth promotion effect on the cuttings in the rootless period was not studied either.

Therefore, researchers have made research on promotion of tea cutting propagation by inoculating AM fungi. For example, according to a novel method for tea seedling mycorrhizal cutting propagation (patent application number

201710942127.9), fungi inoculation and propagation of fungus soil were conducted in days after cutting planting, furrowing was conducted among twig cuttings of seedbeds, the fungus soil was applied and covered with soil, and a small amount of urea was applied and bifenthrin was sprayed at the later stage of inoculation, so as to control tea pests. Single Glomus Intraradices or Glomus Mosseae was adopted, and the effects on the survival rate, callus formation rate, germination rate and later growth performance of different varieties of tea seedlings were studied. The results showed that the highest survival rate of tea seedlings was 89.9%+/-4.1%, the highest callus formation rate was 96.7%+/-5.8%, and the germination rate was as high as

76.0%+/-13.9%. But the method was only suitable for the condition that specific AM fungi were adopted for specific tea tree species. As another example, a method for improving the field mycorrhizal cutting propagation effect of tea seedlings (patent application number: 201910097626.1) was disclosed. A propagated AM fungus efficient strain Rhizophagus Intraradices was spread on cutting seedbeds in advance and strigolactone was sprayed after cutting planting, so as to promote the field mycorrhizal cutting propagation effect of the tea seedlings and substantially increase LUS00614 the mycorrhiza infection rate. The mycorrhiza infection rate reached 94.97%+/-1.5%, and the survival rate reached 99.4%+/-0.23%. The growth performance of the tea seedlings was also improved, with stem height reaching 22.49+/-0.59 cm, root length being 10.31+/-0.35em, the stem dry weight/fresh weight ratio being 34.07%+/-4.3% and the root dry weight/fresh weight ratio being 40.27%+/-3.025%. Clearly, studies have been made on tea seedling propagation by inoculating the AM fungi to the cuttings without the roots; and in the process of tea seedling propagation by inoculating the AM fungi to the cuttings without the roots, adaptation of the specific AM fungi to specific tea varieties and synergy of the specific AM fungi with specific plant hormones on the designated tea varieties have been studied. However, with respect to the combined effect of mixed AM fungi and specific plant hormones on increase of mycorrhizal level and growth performance of the tea seedlings, little has been reported.

SUMMARY In order to solve the above-mentioned technical problems in the prior art, the present invention provides a method for cutting propagation of tea seedlings by inoculating mixed arbuscular mycorrhiza (AM) fungi.

Specifically, the method is implemented through the following technical scheme: The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi comprises the following steps: efficient AM fungi mixed inocula were spread on seedbeds and covered with subsoil, and cuttings were planted; and plant hormones were sprayed in 70-90 days after cutting planting to promote symbiosis of the AM fungi with the tea seedlings. The efficient AM fungi mixed inocula are prepared from Rhizophagus Intraradices, Fumnneliformis Mosseae and Claroideoglomus Etunicatum by mixing in a mass ratio of 1:1:1, and the plant hormones are strigolactone or spermidine.

Preferably, the spraying concentration of the strigolactone was 1.0 umol/L; and the spraying concentration of the spermidine was 0.10 mmol/L.

Preferably, the efficient AM fungi mixed inocula were propagated and prepared by a method for propagating strains by planting clover.

Preferably, the method for propagating the strains comprises the following steps: (1) mixing yellow sand and river sand in a mass ratio of 1:1, and performing radiation sterilization (12 kGy) to obtain a medium for later use;

(2) washing clover seeds by NaOH with mass concentration of 10% for 3-5 min, LU500614 cleaning the seeds with distilled water, soaking the seeds in 75% alcohol for 20 min, cleaning the seeds with distilled water again, and performing drying for later use; (3) applying the seeds obtained in the step (2) and the AM fungal inocula to the medium obtained in the step (1), performing watering and culturing with sterile water for 12 weeks, cutting off the overground part of the clover, collecting the soil containing roots of the clover, and performing drying in the shade to obtain the AM fungal inocula.

Preferably, the clover 1s white clover.

Preferably, the seedbeds have a length of 8-10 m, a width of 1.2-1.3 m and a height of 20-25 cm; and the gap between two adjacent seedbeds is 10-15 cm.

Preferably, the subsoil is yellow-brown acidic soil excavated on a barren slope with no weeds or few weeds, and the covering thickness is 3-5 cm.

Preferably, for the cuttings, axillary buds with a length of 30-50 cm were taken as maternal scionss after spring tea was picked; the maternal scionss were tipped to promote germination of lateral buds, and the lateral buds were cut as the cuttings after growing to 10-15 cm.

Preferably, for cutting planting, the seedbeds were thoroughly watered until the soil water content was 70%-80%, and the soil was compacted; and then the cuttings were planted according to the plant spacing of 0.5-1 cm and the row spacing of 3-5 cm; and after cutting planting, the cuttings were covered with white plastic film, and shaded by shading nets.

Preferably, the method further comprises tea garden management: weeding was conducted manually, and bifenthrin at a concentration of 8 ml/25Kg was sprayed once or twice to control pests; and when the fourth leaf grew out, urea was dressed and was applied twice by 20 kg/mu each time throughout the growth of the tea seedlings.

Compared with the prior art, the present invention has the technical effects as follows: The efficient AM fungi mixed inocula were spread on the seedbeds and covered with the subsoil for cutting planting, and the plant hormones were sprayed in 70-90 days after cutting planting, so as to enhance the infection ability of the mixed AM fungi to the tea cuttings and increase the infection rate. Therefore, the mycorrhizal level of the tea seedlings forming roots is improved, the mycorrhizal propagation effect is enhanced, and the growth performance of the tea seedlings is improved.

According to the present invention, the specific efficient AM fungi mixed LU500614 inocula were combined with the corresponding plant hormones, and then the plant hormones were sprayed in a specific time period after cutting, so that the purposes of increasing the mycorrhizal level of the cuttings and improving the growth performance of the tea seedlings are achieved.

Strigolactone: strigolactones analog, rac-GR24, CAS No.76974-79-3, molecular formula: C17H1405 and molecular weight: 298.29006.

Spermidine: CAS No.124-20-9, molecular formula: C7H19N3 and molecular weight: 145.2.

DESCRIPTION OF THE INVENTION In the following, the technical scheme of the present invention 1s further limited with specific embodiments, but the claimed scope is not limited to the descriptions.

The “AM-free fungal inocula” used in the following experiments were obtained by radiation sterilization (12 kGy) of the same quantity of efficient AM fungi mixed inocula.

I. Experimental method

1. Preparation of the efficient AM fungi mixed inocula: (1) mixing yellow sand (sieved by a 2mm sieve) and river sand in a mass ratio of 1:1, and performing radiation sterilization (12 kGy) to obtain a medium for later use; (2) cleaning white clover seeds by NaOH with mass concentration of 10% for 3- 5 min, cleaning the seeds with distilled water, soaking the seeds in 75% alcohol for 20 min, cleaning the seeds with distilled water again, and performing drying for later use; (3) applying the seeds obtained in the step (2) and the AM fungal inocula to the medium obtained in the step (1), performing watering and culturing with sterile water for 12 weeks, cutting off the overground part of the white clover, collecting the soil containing the roots of the white clover, and performing drying in the shade to obtain the AM fungal inocula.

Wherein, AM fungal inocula are Rhizophagus intraradices, Funneliformis mosseae, and Claroideoglomus Etunicatum respectively.

Experimental inocula: after the above three efficient AM fungus strains were propagated by the white clover to form the AM fungal inocula, Rhizophagus Intraradices, Funneliformis Mosseae and Claroideoglomus Etunicatum were mixed in a mass ratio of 1:1:1, and the efficient AM fungi mixed inocula of the experimental group were obtained.

Control inocula 1: Rhizophagus Intraradices and Funneliformis Mosseae were LU500614 mixed in a mass ratio of 1:1; Control inocula 2: Funneliformis Mosseae and Claroideoglomus Etunicatum were mixed in a mass ratio of 1:1; Control inocula 3: Rhizophagus Intraradices and Claroideoglomus Etunicatum were mixed in a mass ratio of 1:1; Control inocula 4-6: Rhizophagus Intraradices, Funneliformis Mosseae and Claroideoglomus Etunicatum were spread separately.

2. Seedbed construction: (1) location: tea seedling propagation base of Xuetang Group, Hetaoba Village, Meijiang Town, Meitan County, Zunyi City, Guizhou Province; (2) time: experimental research was carried out from 2017 to 2020.

(3) land preparation and bed construction: after deep ploughing and rake levelling in a sunny day, the base, with a length of 8-10, a width of 1.2-1.3 and a height of 20-25 cm, was exposed to the sun for 3-5 days; and the seedbeds were constructed at a spacing of 10-15 cm, and the AM containing fungal inocula were spread on the seedbeds and covered with subsoil by 3-5 cm thick.

The fungus soil was applied in accordance with the standard test of A: 150 kg/mu, B: 300 kg/mu, C: 450 kg/mu and D: 500 kg/mu.

3. Preparation of the cuttings: (1) after spring tea was picked in May-June of the year, fertilizer was applied to promote the growth of buds and leaves, and axillary buds were promoted to grow to be 30-50 cm long to be used as the maternal scions; (2) the maternal scions were tipped to promote lateral buds to germinate, and in October-November of the year, the lateral buds were cut as cuttings after growing to be 10-15 cm long;

4. Cutting management: (1) in October-November of that year, the seedbeds were thoroughly watered until the soil water content is 70-80%, and soil was compacted; (2) the cuttings were planted according to the plant spacing of 0.5-1 cm and the row spacing of 3-5 cm, and after cutting planting, the cuttings were covered with white plastic film and shaded by a black sunshade net; (3) in March-April of the following year, the film was uncovered, the sunshade net was kept, weeding was conducted manually, and plant hormones were sprayed;

(4) after May-June of the following year, according to the actual growth of the LUS00614 tea seedlings, bifenthrin at a concentration of 8 ml/25Kg was sprayed once or twice to control pests; and when the fourth leaf grew out, urea was applied twice by 20 kg/mu, and the tea seedlings were fertilized twice in the growth cycle of the seedbeds.

Plant hormones were sprayed by 5 L/mu.

Strigolactone: 0.5 umol/L, 1 umol/L, 2 umol/L, equal amount of water as control; Spermidine: 0.05 mmol/L, 0.1 mmol/L, 0.2 mmol/L, equal amount of clear water as control.

5. Experimental statistics Infection rate: after the tea seedling cuttings were propagated for 10 months, the roots of the tea seedlings were collected and cut into root segments about lcm long, the root segments were put in a test tube, 10% KOH was added, the root segments were dyed in a water bath at 90°C for about 30 min, cleaned and decolorized, and the number of infected root segments was observed under a microscope in accordance with the following formula: Infection rate (%) = (number of infected root segments/total root segments) x100% Propagation indexes: after the cuttings were propagated for 10 months, the survival rate of the tea seedlings was counted, and the germination rate and callus formation rate of 1,000 tea seedlings were randomly investigated; Growth indexes: after the cuttings were propagated for 10 months, 30 plants were randomly selected from each seedbed, and the plant height, root length, the stem dry weight/fresh weight ratio and the root dry weight/fresh weight ratio of the tea seedlings were calculated.

6. Applicable varieties The experimental method is suitable for national tea varieties (such as Camellia Sinensis ‘Fuding Dabaicha’) suitable for cutting propagation. The Camellia Sinensis ‘Fuding Dabaicha’ was adopted for experiments, and each experiment was repeated 3 times.

II. Experimental results

1. Experiment of inocula inoculation amount (1) influence on AM infection rate of cutting tea seedlings

The inocula were sprayed on the seedbeds according to the inoculation amount LUS00614 described in Table 1 below, and the root infection rate of the cutting tea seedlings was counted.

The results are shown in Table 1 below:

Table 1 Pme pe eww pe ae pe ee pese pe eee pe vee pe we pe ee pe ee Ps ee pe Ame pe ae pe ee wee we [eT pw eee wo mmm we mem Tw ee wm mew

Tw em Table 1 shows that compared with the control inocula and the AM-free fungal inocula, the experimental efficient AM fungi mixed inocula show that as the cuttings were planted on the inoculated seedbeds, the mycorrhizal infection rate increased significantly, and the infection rate would change with the increase of the fungus soil inoculation amount, wherein the infection rate of 300 kg/mu inoculation amount was insignificantly different from that of 450 kg/mu and 500 kg/mu, but was significantly higher than that of 150 kg/mu. Therefore, after comprehensive comparison of inoculation cost and infection effect, the inoculation amount in subsequent experiments was determined to be 300 kg/mu.

(2) influence on propagation indexes of cutting tea seedlings Propagation indexes were calculated for the tea seedlings obtained from the cuttings in the seedbeds inoculated with the inocula at a dose of 300 kg/mu. The results are shown in Table 2 below: Table 2 (%) Rate (%) (%) Table 2 shows that compared with the control inocula and the AM-free fungal inocula, the experimental efficient AM fungi mixed inocula show that by inoculation of the seedbeds with the experimental efficient AM fungi mixed inocula, and planting of the cuttings for tea seedling propagation, the survival rate of the cutting tea seedlings can be greatly increased, and the germination rate and callus formation rate LUS00614 were increased.

(3) influence on growth indexes of cutting tea seedlings Growth indexes were calculated for the tea seedlings obtained from the cuttings in the seedbeds inoculated with the inocula at a dose of 300 kg/mu. The results are shown in Table 3 below: Table 3 Stem Dry Stem Height | Root Length | Weight/Fresh Root Dry (cm) (cm) Weight Ratio Weight/Fresh Weight Ratio (%) (%) Experimental AM-free fungal Table 3 shows that compared with the control inocula and the AM-free fungal inocula, the efficient AM fungi mixed inocula show that by inoculation of the seedbeds with the experimental efficient AM fungi mixed inocula, and planting of the cuttings, the growth performance (such as the plant height, root length, the stem dry weight/fresh weight ratio and the root dry weight/fresh weight ratio) of the cutting seedlings was improved, the quality of the seedlings was guaranteed, and high-quality tea seedlings were produced.

By a summary of data in Table 1, Table 2, and Table 3, a composite AM fungi inoculum was prepared from Rhizophagus Intraradices soil, Fumneliformis Mosseae soil and Claroideoglomus Etunicatum Inocula by mixing in a mass ratio of 1:1:1. The composite AM fungi inoculum was spread on the tea seedling culture seedbeds by

300 kg/mu, and then cuttings were planted. The results show that the infection rate of LU500614 the AM fungi to roots was increased, the propagation quality and the growth performance of the tea seedlings were improved, and thus, the survival rate and rooting rate were increased, growth of tea seedlings was accelerated, the propagation quality was guaranteed, and high-quality tea seedlings were produced.

2. Inoculation of inocula + plant hormone experiment (1) influence on AM infection rate of cutting tea seedlings The efficient AM fungi mixed inocula obtained from the above experiment were adopted, fungus soil was spread on the tea seedling propagation seedbeds by 300 kg/mu, and in 70-90 days after cutting, plant hormones were sprayed by 5L/mu, and the infection rate was calculated according to the above statistical method. The results are shown in Table 4 below: Table 4 Hormones ween [wee Experimental inocula +

1.0 umol /L 97.83 + 0.98a ES eme ee Pme ee Pme [oom M me ea ee es [veer ee wwe [eee ower [eww Coon dere || seen Eve as da] een Table 4 shows that compared with the control inocula and the AM-free fungal inocula the plant hormones sprayed in 70-90 days after cutting could significantly increase the infection rate of AM fungi, and the infection rate of different AM fungi LUS00614 and combinations thereof after inoculation was different from that of hormones of different kinds and at different concentrations. But overall, as was disclosed in the previous research of this research, for example, the method for improving the effect of field mycorrhizal cutting propagation of tea seedlings (patent application No.201910097626.1), spraying of plant hormones could help the AM fungi to establish symbiotic relationship with host tea seedlings, thus increasing the infection rate. Compared with inoculation of a single AM fungus, the method (in which the composite AM fungal inocula were spread to the seedbeds, the cuttings were planted and the plant hormones were sprayed in 70-90 days) has the advantages that the infection rate reached 97% or above, and the infection effect was higher. (2) influence on propagation indexes of cutting tea seedlings Propagation indexes were calculated for the tea seedlings obtained from cuttings in the seedbeds with 1.0umol/L strigolactone and 0.10mmol/L spermidine. The results are shown in Table 5 below. Table 5 Germination | Callus Formation Rate Group Survival Rate (%) Rate (%) (%) Experimental inocula + ; 99.93 + 0.046a 98.69+2.14a 98.69+1.97a strigolactone Experimental inocula +

99.93 £0.055a | 98.95 + 1.87a 98.95 + 2.04a spermidine Control inocula 4 + ; 99.46 +0.132a | 89.97 +1 57ab 90.89 +2.03ab strigolactone Control inocula 4 + _ 99.51+0.089a 89.98 +1.83ab 89.93 + 1.75ab spermidine Control inocula 4 +

98.03 + 0.055b 86.21+ 1.86b 88.21+ 0.88b clear water Experimental inocula +

99.91+0.052ab | 87.54 + 0.9% 86.23 + 1.64b clear water Table 5 shows that compared with the control inocula and the AM-free fungal inocula, the experimental inocula, with strigolactone or spermidine sprayed in 70-90 days after cutting, can increase the survival rate, germination rate and callus formation LUS00614 rate of the tea seedlings and significantly improve the propagation performance. (3) influence on growth indexes of cutting tea seedlings Growth indexes were calculated for the tea seedlings obtained from cuttings in the seedbeds with 1.0umol/L strigolactone and 0.10mmol/L spermidine. The results as shown in Table 6 below. Table 6 ; Stem Dry Root Dry Plant Height | Root Length . . Group weight/fresh weight/fresh (cm) (cm) . . . . weight ratio (%) |weight ratio (%) Experimental inocula + 27.08 + 0.21a| 12.45 +0.12a | 40.12+2.01a | 49.97 +1.88a strigolactone Experimental inocula + 27.05 + 1.03a| 1298+ 1.03a | 41.85+ 0.99a | 51.23 +1.37a spermidine Control inocula 4 + ; 4.51 + 0.76ab | 10.29+0.51b | 33.88#1.43bc | 40.56 +3.14bc strigolactone Control inocula 4 + _ 24.09+ 1.03b | 10.17 0.83b | 34.12+ 0.84b | 41.32+0.95bc spermidine Control inocula 4 +

18.44+0 45c | 8.83 + 1.17c | 27.49+ 1.13c | 31.62+2.03c clear water Experimental inocula + clear 24 14+0.66b | 11.10 +0.93ab | 35.47 +1. 88ab | 45.91+1.96ab water Table 6 shows that compared with the control inocula 4 and the AM-free fungal inocula, the experimental inocula, with strigolactone or spermidine sprayed in 70-90 days after cutting, can significantly improve the growth performance (such as the plant height, root length, the stem dry weight/fresh weight ratio and the root dry weight/fresh weight ratio) of the tea seedlings, promote growth of the tea seedlings and produce high-quality tea seedlings.

By summary of data in Table 4, Table 5, and Table 6, the spraying of plant LUS00614 hormones in 70-90 days after cutting propagation can promote the infection of mixed AM fungi to cutting tea seedlings, and lead to better infection effect. In addition, the cutting survival rate, germination rate and callus formation rate were increased, the growth performance of the tea seedlings in the later stage was also improved, and the seedling formation was accelerated. Wherein, the method, in which the mixed AM fungal inoculum (prepared from the Rhizophagus Intraradices Inocula, Funneliformis Mosseae Inocula and Claroideoglomus Etunicatum Inocula by mixing in a mass ratio of 1:1:1) was spread on the tea seedling culture seedbeds by 300 kg/mu, the cuttings were planted in 70-90 days, and the plant hormones were sprayed, displays that the infection effect was the best, and the growth performance of tea seedlings was the best.

3. Research on timing of inoculation Research design: Design 1: the inocula were spread on the seedbeds by the spreading method of the present invention, and the conclusion derived from the above-mentioned experiments on the inoculation amount of the efficient AM fungi mixed inocula was used as result data.

Design 2: other cutting seedling propagation methods were implemented in accordance with the experiment method of the inoculation amount of the efficient AM fungi mixed inocula, and the inocula were inoculated by ditching and spreading in 30 days, 60 days, 70 days and 90 days after cutting planting.

Inocula: = Rhizophagus Intraradices, Funneliformis Mosseae and Claroideoglomus Ftunicatum were mixed in a mass ratio of 1:1:1.

The inoculation amount was 300 kg/mu, and each design group was repeated 3 times.

Statistics of the infection rate are shown in Table 7 below: Table 7 Influence of different inoculation timing of experimental inocula on infection rate ne | 21 | Experimental Inocula Experimental Inocula + Timing of Inoculation +0.10mmol/L Inocula 1.0umol/L Spermidine Strigolactone

[ow [oom [woos | women [oi [ees [on | wweom [wn [ews [won | wie According to Table 7, the influence of the inoculation timing on the infection rate was insignificantly different. However, with respect to inoculation after cutting, the white plastic film and the sunshade nets over the seedbeds were uncovered, furrowing was conducted among the cutting seedlings for spreading of the efficient AM fungi mixed inocula, and the inocula were covered with soil and film after being spread; but the tea seedlings were in the growing period at the time and were easily damaged and affected in growth. In addition, the labor intensity was increased and the propagation cost was increased. Therefore, in the research process, aiming at the infection rate as an important consideration index, the researcher decided to inoculate the efficient AM fungi mixed inocula before cutting planting, and the plant hormones were sprayed in 70-90 days after cutting, so as to greatly increase the root infection rate and the mycorrhizal level of tea seedlings, improve the propagation performance and growth performance of the tea seedlings, and improve the propagation quality of the tea seedlings.

The specific operation method of the present invention is simple, low in labor intensity and less likely to damage the seedlings, improves the propagation quality and growth efficiency of the tea seedlings, can be applied and popularized in development of the tea industry, and increases the economic benefit of tea farmers.

Other unsettled issues of the present invention should be solved with reference to the prior art, or common knowledge and conventional technical means well known to those skilled in the art.

The above-mentioned are only preferred embodiments of the present invention, but the protection scope of the present invention is not limited to this. Anyone familiar with the technical field, who makes equivalent substitution or change according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, should be covered within the protection scope of the present invention.

Claims (10)

CLAIMS LU500614

1. A method for cutting propagation of tea seedlings by inoculating mixed arbuscular mycorrhiza (AM) fungi strains, characterized in that efficient AM fungi mixed inocula were spread on seedbeds, and covered with subsoil, and cutting was planted; and plant hormones were sprayed in 70-90 days after cutting; the efficient AM fungi mixed inocula were prepared from Rhizophagus Intraradices, Funneliformis Mosseae and Claroideoglomus Etunicatum by mixing in a mass ratio of 1:1:1; and the plant hormones are strigolactone or spermidine.

2. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that the spraying concentration of the strigolactone was 1.0 umol/L; and the spraying concentration of the spermidine was 0.10 mmol/L.

3. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that the efficient AM fungi mixed inocula were propagated and prepared by a method for propagating strains by planting clover.

4. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 3, characterized in that the method for propagating the strains comprises the following steps: (1) mixing yellow sand and river sand in a mass ratio of 1:1, sieving the sand by a 2mm sieve and performing radiation sterilization (12 kGy) to obtain a medium for later use; (2) washing clover seeds by NaOH with mass concentration of 10% for 3-5 min, cleaning the seeds with distilled water, soaking the seeds in 75% alcohol for 20 min, cleaning the seeds with distilled water again, and performing drying for later use; (3) applying the seeds obtained in the step (2) and the AM fungal inocula to the medium obtained in the step (1), performing watering and culturing with sterile water for 12 weeks, cutting off the overground part of the clover, collecting the soil containing roots of the clover, and performing drying in the shade to obtain the AM fungal inocula.

5. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 3 or 4, characterized in that the clover is white clover.

6. The method for cutting propagation of the tea seedlings by inoculating the LUS00614 mixed AM fungi according to claim 1, characterized in that the seedbeds have a length of 8-10 m, a width of 1.2-1.3 m and a height of 20-25 cm; and the gap between two adjacent seedbeds is 10-15 cm.

7. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that the subsoil is yellow- brown acidic soil, and covering thickness of the soil 1s 3-5 cm.

8. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that axillary buds with a length of 30-50 cm were taken as maternal scionss after spring tea was picked; the maternal scionss were tipped to promote germination of lateral buds, and the lateral buds were cut as cuttings after growing to 10-15 cm.

9. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that for cutting planting, the seedbeds were thoroughly watered until the soil water content was 70%-80%, and the soil was compacted; and then the cuttings were planted according to plant spacing of

0.5-1 cm and row spacing of 3-5 cm; after cutting planting, the cuttings were covered with white plastic film, and shaded by shading nets.

10. The method for cutting propagation of the tea seedlings by inoculating the mixed AM fungi according to claim 1, characterized in that the method further comprises tea garden management: weeding was conducted manually, and bifenthrin at a concentration of 8 ml/25Kg was sprayed once or twice to control pests; and when the fourth leaf grew out, urea was dressed and was applied twice by 20 kg/mu each time throughout growth of the tea seedlings.