Application of benzothiadiazole in enhancing stability of photosynthetic system of pinellia ternate and improving drought tolerance of pinellia ternate

Abstract

The invention discloses application of benzothiadiazole in enhancing stability of a photosynthetic system of pinellia ternate and improving drought tolerance of pinellia ternate, and belongs to the technical field of planting of traditional Chinese medicinal materials. It is found that the drought stress symptom of the pinellia ternate can be remarkably relieved by spraying the benzothiadiazole, the relative water content of leaves is increased, the photosynthetic system stability of the pinellia ternate under drought stress is enhanced, and therefore the drought tolerance of the pinellia ternate is improved. The method is used for improving the drought tolerance of pinellia ternate and improving the economic benefit of pinellia ternate planting, is easy to operate, convenient to implement, remarkable in effect, low in input cost and easy to accept and master by medicine farmers.

Description

Technical Field

[0001] The invention belongs to the technical field of Chinese medicinal material planting, and particularly relates to the application of benzothiadiazole in enhancing the stability of the photosynthetic system of pinellia ternata and improving the drought resistance of pinellia ternata. Background Art

[0002] Pinellia ternata (Thunb.) Breit is a perennial herbaceous plant of the genus Pinellia in the family Araceae. Its dried tuber is a traditional Chinese medicinal material with many important functions such as drying dampness and resolving phlegm, relieving adverse reactions and stopping vomiting, clearing away lumps and dispersing knots. Pinellia ternata has a shallow root system, is afraid of drought and waterlogging, tolerates shade and fears the sun. Wild Pinellia ternata is often found in the damp grass or under the forest on the hillside or by the stream. Due to the abuse of modern agricultural herbicides, frequent extreme weather and over-exploitation of wild Pinellia ternata resources, wild Pinellia ternata resources are scarce, and artificial cultivation has become the main way to obtain Pinellia ternata medicinal materials.

[0003] During the growth period of Pinellia ternata, water is an important environmental factor affecting its growth and development. Drought stress can cause non-physiological seedling collapse, resulting in reduced yield and decreased tuber quality. Photosynthesis provides energy for plant growth and development, and is also the basis for its yield formation. Drought can inhibit photosynthetic electron transfer, leading to the generation of excess excitation energy, causing plant photoinhibition and even destruction of photosynthetic machinery, and hindering photosynthetic carbon assimilation. Therefore, improving the drought tolerance of Pinellia ternata is crucial to maintaining its yield.

[0004] The rapid chlorophyll fluorescence induction kinetic curve (OJIP curve) mainly reflects the changes in the primary photochemical reaction of photosystem II (PSII) and the structure and state of the photosynthetic apparatus. The rapid chlorophyll fluorescence induction kinetic analysis (JIP-test) is an analysis method based on the energy flow of biofilms. The parameters obtained can be used to deeply study the primary reaction of photosynthesis, the absorption, conversion and dissipation of light energy by photosynthetic organs, and the state of plant photosynthetic apparatus. The chlorophyll fluorescence parameters obtained by slow-phase fluorescence kinetic analysis can be used to analyze the actual light energy utilization and distribution of the photosystem under light after the dark reaction of photosynthesis is initiated. Chlorophyll fluorescence induction technology has become a powerful tool for evaluating plant drought tolerance due to its non-destructive, accurate and rapid characteristics.

[0005] Benzothiadiazole (BTH) is a typical plant disease resistance inducer. A large number of studies have shown that the application of BTH can make plants produce stronger immune responses to pathogen infection, and has become an important strategy for plant disease prevention and control. At present, it has been found that the application of BTH can effectively prevent and control a variety of diseases such as potato early blight, banana anthracnose, tobacco bacterial wilt, bean rust, black spot of thick-skinned melon, bacterial angular spot of tomatoes and peppers, and grape gray mold. There is no prior art report on the role of BTH in drought stress in Pinellia ternata. Summary of the invention

[0006] The purpose of the present invention is to provide an application of benzothiadiazole in enhancing the stability of the photosynthetic system of Pinellia ternata and improving the drought resistance of Pinellia ternata. The purpose of the present invention is also to provide a method for enhancing the stability of the photosynthetic system of Pinellia ternata under drought stress and a method for improving the drought resistance of Pinellia ternata.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] The application of benzothiadiazole in enhancing the stability of the photosynthetic system of Pinellia ternata is further applied under drought stress.

[0009] Application of benzothiadiazole in improving drought tolerance of Pinellia ternata.

[0010] Application of benzothiadiazole in the preparation of preparations for enhancing the stability of the photosynthetic system of Pinellia ternata.

[0011] Application of benzothiadiazole in preparing preparations for improving drought resistance of Pinellia ternata.

[0012] A method for enhancing the stability of the photosynthetic system of Pinellia ternata under drought stress or improving the drought tolerance of Pinellia ternata is to spray a benzothiadiazole solution on Pinellia ternata before or during drought. The concentration of the benzothiadiazole solution is preferably 50-150 μM, more preferably 100 μM.

[0013] The invention has the beneficial effects that spraying BTH can significantly alleviate the drought stress symptoms of Pinellia ternata, increase the relative water content of leaves, and enhance the stability of the photosynthetic system of Pinellia ternata under drought stress, thereby improving the drought resistance of Pinellia ternata and improving the economic benefits of Pinellia ternata planting. The invention is simple to operate, convenient to implement, has significant effects, low investment cost, and is easily accepted and mastered by medicinal farmers. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 To investigate the effects of BTH application on leaf phenotypes of Pinellia ternata under drought stress.

[0015] Figure 2 The effect of BTH application on the relative water content of Pinellia ternata leaves under drought stress. Different letters indicate significant differences (P<0.05), the same below.

[0016] Figure 3 Effect of BTH on chlorophyll fluorescence parameters F in leaves of Pinellia ternata under drought stress v / F m (A), influence of [Y(II)](B), ETR(C), and qP(D).

[0017] Figure 4 To study the effect of BTH application on the photosynthetic performance index of Pinellia ternata leaves under drought stress.

[0018] Figure 5 The OJIP curve (A) and phase ΔV of Pinellia ternata leaves under drought stress were shown in Figure 2. t (B) impact. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below with reference to the examples, but the embodiments of the present invention are not limited thereto.

[0020] Example 1

[0021] Select Pinellia tubers of uniform size and plant them in seedling pots. Cover the pot with soil to a depth of 5 cm for seedling cultivation. Wait until all three leaves of Pinellia are fully unfolded, and select Pinellia plants with uniform growth as experimental materials.

[0022] Using deionized water as solvent, a BTH solution with a final concentration of 100 μM and a 30% polyethylene glycol-6000 (PEG-6000) solution were prepared. Four groups were set up in the experiment: (1) Control group: spraying deionized water and then watering normally; (2) DS treatment group: spraying deionized water and then watering with 30% PEG-6000 solution; (3) BTH treatment group: spraying 100 μM BTH solution and then watering normally; (4) BTH+DS treatment group: spraying 100 μM BTH solution and then watering with 30% PEG-6000 solution. BTH was sprayed once in the morning and evening, and the BTH solution was evenly spread on the leaves of Pinellia ternata during spraying. PEG-6000 was watered 12 hours after the second spraying to simulate drought treatment for 12 days, and the following analysis was performed.

[0023] The four groups of samples were analyzed by fast-phase fluorescence kinetics using a plant efficiency analyzer (Handy PEA, Hansatech, UK), with four replicates per group. The four groups of samples were analyzed by slow-phase fluorescence kinetics using a portable modulated chlorophyll fluorescence meter (MINI-PAM-II, WALZ, Germany), with three replicates per group. Relative water content determination: After sampling, the leaves were cleaned and the fresh weight (W) was measured using an electronic balance. f ), immerse the leaves in a ziplock bag filled with deionized water and place them in a dark environment for 24 h until constant weight is reached. After wiping off the water, the saturated fresh weight (W t ), then the leaves were placed in an oven at 105°C for 30 min, and then dried at 80°C to constant weight, and the dry weight (W d ), according to the following formula (RWC=(W f -W d ) / (W t -W d)×100%) to calculate the relative water content of Pinellia ternata leaves, and each treatment was repeated 3 times. All data are mean ± SD, and SPSS23.0 software was used for one-way analysis of variance and Duncan multiple comparison analysis (P<0.05).

[0024] The fluorescence parameters measured using chlorophyll fluorescence induction technology are: PSII maximum photochemical efficiency (F v / F m ); actual photosynthetic efficiency [Y(II)]; electron transfer rate (ETR); photochemical quenching coefficient (qP); performance index based on absorbed light energy (PI ABS ); minimum fluorescence intensity after dark adaptation (F o ); Fluorescence intensity at the J point (2ms) of OJIP (F J ); Fluorescence intensity at point I (30 ms) of OJIP (F I ); Maximum fluorescence intensity after dark adaptation (F m ); initial slope of the OJIP fluorescence induction curve (M o ); the relative variable fluorescence intensity at point J (2ms) (V J ); The area enclosed by the standardized OJIP fluorescence induction curve and the y-axis (S m ); the captured exciton transfers the electron to the electron transport chain exceeding Q A The probability of other electron acceptors (ψ o ); quantum yield for electron transfer Quantum yield for reduction of terminal electron acceptor on the acceptor side of PSI Quantum ratio for heat dissipation The number of active reaction centers per unit area (RC / CS m ); Light energy absorbed per unit leaf area (ABS / CS m ); Light energy captured per unit leaf area (TR o / CS m ); quantum yield of electron transfer per unit leaf area (ET o / CS m ); the amount of light absorbed per unit active reaction center (ABS / RC); the amount of light captured by the unit active reaction center for the reduction of Q A Energy (TR o / RC); the energy captured by a unit active reaction center for electron transfer (ET o / RC; the energy dissipated per unit active reaction center (DI o / RC).

[0025] like Figure 1As shown in the figure, compared with the control, the leaves of Pinellia ternata in the DS treatment group turned yellow, wilted and curled; compared with the DS treatment group, the degree of yellowing of Pinellia ternata leaves after BTH+DS treatment was reduced, no obvious curling was observed, and the symptoms of drought stress were alleviated. This result shows that the drought tolerance of Pinellia ternata in the BTH+DS treatment group is significantly better than that in the DS treatment group.

[0026] like Figure 2 As shown, compared with the control group, the relative water content of leaves in the DS treatment group decreased by 21.63%, indicating that water deficit affected the leaf morphology; compared with the DS treatment group, the relative water content of leaves in the BTH+DS treatment group increased by 12.40%, suggesting that spraying BTH can effectively maintain the water content of Pinellia ternata leaves under drought stress conditions and alleviate the drought stress symptoms of Pinellia ternata leaves.

[0027] like Figure 3 As shown, compared with the control group, the DS treatment group significantly reduced the v / F m , Y(II), ETR and qP; compared with the DS treatment group, the above parameters in the BTH+DS treatment group increased significantly. These results show that spraying BTH can alleviate the photoinhibition of the photosynthetic system under drought stress, alleviate the damage of drought stress to the photosynthetic apparatus of Pinellia ternata leaves and the damage to the PSII reaction center, improve the electron transfer rate and photochemical efficiency, and thus enhance the drought tolerance of Pinellia ternata.

[0028] PI ABS It is a comprehensive performance index reflecting the activity of PSII. Figure 4 As shown, compared with the control group, PI ABS Compared with the DS treatment group, the PI of the BTH+DS treatment group was significantly reduced. ABS This result shows that the application of BTH can effectively improve the overall state of the photosynthetic apparatus of Pinellia ternata leaves under drought stress, maintain the stability of the photosynthetic system, and thus improve the drought tolerance of Pinellia ternata plants.

[0029] like Figure 5 As shown in (A), compared with the control group, the DS treatment group caused the OJIP curve to deform, and the J, I, and P phases all decreased significantly; compared with the DS treatment group, the BTH+DS treatment group could partially restore the OJIP curve to the control line shape. Figure 5 As shown in (B), compared with the control group, ΔK-band, ΔJ-band and ΔI-band in the DS treatment group increased; compared with the DS treatment group, the increase of the above parameters in the BTH+DS treatment group was alleviated. The above results indicate that DS treatment not only damaged the oxygen-evolving complex (OEC) on the donor side of PSII in P. ternata leaves, but also inhibited the electron transfer on the acceptor side, while the application of BTH played a protective role on both the donor and acceptor sides of PSII in P. ternata under drought stress.

[0030] As shown in Table 1, compared with the control group, the S m , o , and Lower, M o 、V J and Compared with the DS treatment group, the changes in the above parameters in the BTH+DS treatment group were significantly alleviated. These results indicate that DS treatment leads to a decrease in the opening degree of the active PSII reaction center and the PQ pool capacity, and the PSII receptor side Q A The ability to transfer electrons decreases; under drought stress, the application of BTH can lead to reduced energy dissipation in the electron transfer process, increased PQ pool capacity, and improved obstruction of the photosynthetic electron transport chain on the PSII receptor side.

[0031] Table 1 Effects of BTH application on the PSⅡ receptor side of Pinellia ternata leaves under drought stress

[0032]

[0033] As shown in Table 2, compared with the control group, the RC / CS m ,ABS / CS m ,TR o / CS m , E.T. o / CS m , E.T. o / RC reduced, ABS / RC, TR o / RC、DI o / RC increased; compared with the DS treatment group, the above except ET in the BTH+DS treatment o All parameters except RC were significantly alleviated. These results indicate that DS treatment inactivated the PSII reaction center, reduced the ability to capture light energy and electron transfer, and caused the excess light energy to be consumed in the form of heat dissipation. Under drought stress, the application of BTH played a protective role on photosynthetic electron transfer and reaction center, effectively reducing heat dissipation and thus using more light energy for electron transfer.

[0034] Table 2 Effects of BTH application on specific activity parameters of Pinellia ternata leaves under drought stress

[0035]

[0036] The results of this example show that spraying BTH can significantly alleviate the drought stress symptoms of Pinellia ternata, increase the relative water content of leaves, and enhance the stability of the photosynthetic system of Pinellia ternata under drought stress, thereby improving the drought resistance of Pinellia ternata. The invention has low investment cost, obvious effect, and is easy to implement, and can increase the economic benefits of Pinellia ternata planting in arid areas.

[0037] The above embodiments are only used to help illustrate the present invention. The implementation methods of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. Application of benzothiadiazole in enhancing the stability of the photosynthetic system of Pinellia ternata.

2. The use according to claim 1, characterized in that: The application is application under drought stress.

3. Application of benzothiadiazole in improving drought resistance of Pinellia ternata.

4. Application of benzothiadiazole in the preparation of preparations for enhancing the stability of the photosynthetic system of Pinellia ternata.

5. Application of benzothiadiazole in the preparation of preparations for improving the drought resistance of Pinellia ternata.

6. A method for enhancing the stability of the photosynthetic system of Pinellia ternata under drought stress or a method for improving the drought tolerance of Pinellia ternata, characterized in that: The method comprises spraying a benzothiadiazole solution on the pinellia before or during drought.

7. The method according to claim 6, characterized in that: The concentration of the benzothiadiazole solution is 50-150 μM.

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