Method for identifying adversity stress of roots of vegetable and fruit crops in seedling stage

Abstract

The invention discloses a method for identifying adversity stress of roots of vegetable and fruit crops in the seedling stage, and belongs to the technical field of root development research of plants in the seedling stage. The method for identifying the adversity stress of the roots of the vegetable and fruit crops in the seedling stage comprises the following steps: (1) assembling a root identification research device which comprises a root growth observation container, a feeding module, a container bracket, a receiving disc and an observation device which are arranged in a matched manner; (2) filling a growth medium; (3) seedling raising and field planting; (4) plant growth management; and (5) observing plant root and overall growth and development. Aiming at the defects of the existing fruit and vegetable crop root system adversity stress identification research method, the growth environment of the actual fruit and vegetable crops can be simulated by applying a low-cost simple device, and various independent or composite adversity stress identification of water, fertilizer, pesticide and the like can be remotely and automatically carried out; and continuous growth and development observation and research of root adversity stress response can be carried out.

Description

Technical Field

[0001] The invention belongs to the technical field of research on root development of plants at the seedling stage, and in particular relates to a method for identifying root adverse environment stress of vegetable and fruit crops at the seedling stage. Background Art

[0002] Plant roots are the nutritional organs of plants, which have the functions of fixing and supporting the plant body, as well as absorbing, transporting, distributing and storing nutrients. For a long time, plant roots have been neglected because they are located underground, and research on root growth and development lags far behind that of the aboveground parts. At the same time, different soil and environmental conditions have a great impact on root growth and development, which also leads to lags and uncertainties in root research.

[0003] The growth status of crops in the seedling stage plays a decisive role in the later growth and yield, and crops face a lot of adverse stresses during the entire growth cycle, such as drought, waterlogging, lack of fertilizer, diseases, etc. The growth and development of the roots plays a decisive role in the nutritional health of the aboveground parts. For the accurate identification of rootstock germplasm resources, the selection and breeding of varieties and the study of grafting mechanism, the study of roots in the seedling stage is particularly important. Traditional research on root stress in the seedling stage is mainly carried out through culture dishes, germination bags, potted plants, CT scanning and other methods. However, the above methods have certain defects in root system research. First, culture dishes and germination bags mainly use culture media or nutrient solutions as the root development environment, which is quite different from the actual growth environment of plant roots, affecting the accuracy of the research results. Secondly, when using potted research, the roots need to be washed during soil culture, which is easy to cause root damage and discontinuity of observation; nutrient solution is used during hydroponics, which has a greater impact on root type composition and root development. Finally, although CT scanning can observe the continuous overall changes in plant root shape, it is difficult to observe the color of the root system and the occurrence of root diseases. It is costly, has health and safety risks, has a high operating threshold, and has high requirements for research sites, making it difficult to popularize on a large scale.

[0004] At present, the treatment and identification of crop root stress rely heavily on manual labor, and there are certain differences from the actual situation. For example, water stress requires manual watering, which is difficult to quantify, and fertilizer control is mainly a gradual reduction after a single surplus or shortage. It is difficult to examine the process and continuous performance of root diseases. At the same time, it is difficult to carry out the identification of compound treatments such as water, fertilizer, and medicine for the roots, and it is difficult to carry out stress treatment identification continuously. Summary of the invention

[0005] In view of the defects of existing methods for studying root growth and development, the present invention provides a method for identifying root adversity stress in the seedling stage of fruit and vegetable crops. In this method, a low-cost simple device can be used to simulate the growth environment of fruit and vegetable crops in the seedling stage, and research on the identification of continuous or periodic single or compound adversity stress on the roots can be conducted.

[0006] The technical solution of the present invention is achieved in this way:

[0007] A method for identifying root stress of fruit and vegetable crops at the seedling stage, comprising the following steps:

[0008] (1) Assembly of the root identification research device

[0009] The root identification research device comprises a root growth observation container, a feeding module, a container support, a receiving tray and an observation device that are matched and arranged;

[0010] The root growth observation container is a transparent rectangular flat barrel structure, including a first long side wall, a first short side wall, a second long side wall, a second short side wall and a container bottom plate; the first short side wall and the second short side wall are arranged opposite to each other and have equal widths, and the widths of the first short side wall and the second short side wall are 1-3 cm respectively; the first long side wall and the second long side wall are arranged opposite to each other and have equal widths, and the widths of the first long side wall and the second long side wall are 10-80 cm respectively; an opaque shielding layer is detachably provided on the outer side of the first long side wall, a ruler is provided on the second long side wall, and the second long side wall is provided with a set of length and angle measurement rulers that can slide left and right and are connected to the upper and lower sides by clips respectively on the upper and lower sides, and an observation device is provided on the outer side of the second long side wall; a plurality of bottom holes are provided on the container bottom plate;

[0011] The feeding module comprises a hose and a filter valve, a watering device, a check valve, a tee and a water outlet arranged on the hose in sequence; the water outlet end is arranged in the root growth observation container;

[0012] Assemble the first long side wall, the first short side wall, the second long side wall, the second short side wall and the container bottom plate of the root growth observation container into a root growth observation container with a rectangular flat barrel structure; connect the filter valve, the watering device, the check valve, the tee and the water outlet of the feeding module to the hose in sequence, and set the water outlet in the root growth observation container; place the observation device on the outside of the first long side wall;

[0013] (2) Growth medium filling

[0014] Filling the root growth observation container installed in step (1) with growth medium;

[0015] (3) Seedling cultivation and planting

[0016] After the growth medium is filled in step (2), a hole is dug on the upper surface of the growth medium in the root growth observation container, and the seeds of the fruit and vegetable crops used for stress identification are sown with the radicle facing downward, and then covered with the growth medium;

[0017] (4) Plant growth management

[0018] The root growth observation container is placed on the container support, and the receiving tray is arranged below the container support at a position corresponding to the bottom hole; water is added to the watering device end of the feeding module, and stress factors are added according to the needs of the stress identification research; the water outlet of the feeding module is inserted into the growth medium, and the water outlet is arranged around the seeds of fruit and vegetable crops or between two seeds; the stress factors of water, fertilizer, and bacteria are added and the growth management is carried out through the feeding module;

[0019] (5) Observation of plant roots and overall growth and development

[0020] The plant roots are photographed, recorded and observed by the observation device arranged on the outside of the second long side wall; and the opaque shielding layer on the outside of the first long side wall is opened for observation and recording, and the difference in root development exposed to external light and that not exposed to external light can be compared; by observing and recording the photographic results and data of root stress of fruit and vegetable crops, root stress of fruit and vegetable crops can be identified.

[0021] Preferably, in step (1):

[0022] The root growth observation container is prepared by using a transparent plastic plate.

[0023] Further preferably, a specific assembly method of the root growth observation container is: gluing the first and second long side transparent plastic plates of 5 mm thickness and 10-80 cm width, the first and second short side transparent plastic plates of 5 mm thickness and 1-3 cm width, and the 5 mm thick bottom plate into a rectangular flat barrel structure.

[0024] The bottom hole is preferably a hole with a diameter of 1 cm; further preferably, the number of the bottom holes is 3-8; the bottom holes are used to flow out excess water, and the receiving tray is used to collect the excess water flowing out of the bottom holes.

[0025] Further preferably, a push-pull plate is provided on the bottom plate of the container to adjust the size and opening and closing of the bottom hole.

[0026] Further preferably, the root growth observation container further comprises a gauze, which is adhered and covered on the inner side of the bottom plate of the container, matches the bottom hole, and is used to prevent sand and soil from being lost. The gauze is preferably an 800 mesh gauze.

[0027] The opaque shielding layer is at least one of opaque paper, cloth or board. The opaque shielding layer can prevent the crop roots on one side of the first long side wall from being exposed to light, and when it is necessary to observe the growth of the crop roots on one side of the first long side wall, the opaque shielding layer can be removed to observe, take photos or videos without affecting the natural growth state of the roots.

[0028] The inner diameter of the hose is adapted to the component joints of the filter valve, the watering device, the check valve, the tee and the water outlet.

[0029] The water outlet is arranged at one third of the height of the root growth observer. The middle pipe of the water outlet is a spiral structure, and a plurality of spiral water outlet holes are arranged on the spiral structure of the water outlet. The plurality of water outlet holes and the spiral arrangement can effectively slow down the water flow speed and reduce the impact force of water on the growth medium, so as to reduce the damage of the water flow to the surrounding roots and the formation of cavities in the growth medium.

[0030] The observation device includes at least one of the devices for video recording, photographing or observation. It can be a fixed or mobile photographing or video recording device. The observation device also includes chlorophyll fluorescence imaging, far infrared imaging and other monitoring and imaging instruments for measuring physiological functions such as photosynthesis, etc., to examine the dynamic performance of physiology and phenotype. When there are many observation devices, automatic guide rails can be installed for cyclic timed shooting and monitoring; it can also be combined with network equipment for remote control, inspection, information acquisition and change of research methods.

[0031] Preferably, in step (2):

[0032] The growth medium is at least one of a seedling medium, sand, gravel or farmland soil; the growth medium used is added with corresponding stress factors according to the needs of the root adversity stress experiment, and the stress factors include at least one of stress factors such as high salt, high alkali or water and fertilizer deficiency.

[0033] Preferably, the growth medium is mixed with water according to conventional seedling raising standards before filling the root growth observation container. Preferably, the root growth observation container is filled to five sixths of the container.

[0034] Preferably, in step (3):

[0035] The vegetable and fruit crop seeds are soaked and germinated before sowing.

[0036] Further preferably, during the sowing, seeds of two or more different crops can be sown to study the root interaction relationship between crops under adverse stress. Due to the root interaction between species under adverse stress, in the traditional root observation process, there is a defect that the plant roots are taken out of the growth medium for observation, and it is difficult to observe the mutual influence process of the roots between species during the growth process in real time. Therefore, the root growth observation container and the identification method thereof in the present invention can realize the real-time observation of the mutual influence of the roots between crops under adverse stress and the entire root development process; it is of great significance for the study of the interaction between species of the roots of fruit and vegetable crops under adverse stress conditions.

[0037] Preferably, in step (4):

[0038] The stress factor is at least one of high salt, high alkali or water and fertilizer deficiency; if the stress factor needs to be mixed with water for irrigation, it is added to the watering device together with water for mixing and then added; if the stress factor does not need to be mixed with water for irrigation, the stress factor can be applied alone. Further preferably, in the process of adding water, water, fertilizer and medicine can be added at the same time; according to the research purpose, only the water outlet, or two or three combined water outlets for water, fertilizer and medicine, or independent water outlets for water, fertilizer and medicine can be inserted.

[0039] The growth management specifically involves processing water, nutrition (fertilizer), medicine, light, and temperature according to crop growth rules or research purposes. The required water, fertilizer, and medicine are applied through the water outlet; light and temperature are controlled through the growth environment.

[0040] Further preferably, according to the research needs, each root growth observation container can be connected to one water outlet for adding only water or multiple water outlets with different water, fertilizer and medicine as needed. At the same time, each feeding module can be connected to one growth observation container or multiple growth observation containers, but it is necessary to ensure that the water adding equipment allocation capacity of different materials for the same treatment in each experiment is the same. The duration, frequency and flow rate of watering (or fertilizer, medicine) or different combinations of water, fertilizer and medicine can be remotely controlled through the network, and the automatic watering mode can be set according to the experimental design.

[0041] Preferably, in step (5):

[0042] The root stress identification is carried out by examining the phenotype, physiological and biochemical indicators of the above-ground and underground roots of the plants, combined with image data obtained by taking photos and imaging during the growth process, to identify the root stress of fruit and vegetable crops.

[0043] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0044] 1. The present invention aims at the defects of existing research methods for identifying root stress of fruit and vegetable crops. By using a low-cost simple device (root growth observation container and feeding module), the actual growth environment of fruit and vegetable crops can be simulated to conduct remote and automated identification of various single or combined stresses of water, fertilizer, medicine, etc., including simultaneous continuous treatment of different stress factors at regular or irregular intervals, treatments of different durations, treatments of different sequences, and treatments of different intensities, etc., and continuous remote observation research of the response of roots or roots and aboveground parts to stress can be conducted, which can be used for cultivation technology research, germplasm resource evaluation and identification, variety breeding, physiological and biochemical research, etc.

[0045] 2. The root growth observation container used in the research method of the present invention can better realize the comprehensive observation of the root growth and development of the fruit and vegetable crops planted therein through the transparent side and the container gap of 1-3 cm, and there is no need to damage the roots; at the same time, the optimal restoration state of the root growth without light can be achieved by disassembling and assembling the opaque shielding layer on the opaque side (the outer side of the first long side wall is detachably provided with an opaque shielding layer), and the opaque shielding layer can be removed at any time for observation and recording, as well as comparison with the transparent state on the other side; the root growth observation container can be filled with various growth media, and the effects of various growth media and growth medium compactness and other conditions on the root growth and development of fruit and vegetable crops in the seedling stage can be studied, as well as the synergistic interaction between the growth medium and the stress environment such as water, fertilizer and medicine; the microorganisms and pathogens in the growth medium can be designed to study and observe their effects on root development, and observe and analyze the appearance and physiological manifestations of the whole process of root diseases and insect pests.

[0046] 3. The research method for identifying root stress of fruit and vegetable crops at the seedling stage of the present invention can be used for studying the interaction between species or between varieties within a species by planting two or more different crops or different varieties in a growth observation container, and continuous observation and research on the seedling interaction between species can be carried out through the root growth observation container, which is of great value for real-time observation and research of roots.

[0047] 4. The research method for identifying root stress of fruit and vegetable crops at the seedling stage of the present invention can obtain complete root specimens at different stress stages through the combination and disassembly of growth containers, which can be used for teaching, popular science, and research on root development, and has good practicality and economic promotion value.

[0048] 5. The research method for identifying root stress of fruit and vegetable crops at the seedling stage of the present invention realizes automatic and precise acquisition of data through remote and automated addition of water, fertilizer, and medicine, combined with network equipment, connecting automated guide rails and detection, photography, and video equipment, and realizes high-throughput root stress identification, which can save a lot of manpower, improve accuracy, and reduce human errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic structural diagram of the root growth observation container (opaque shielding layer separated state) provided in Example 1 of the present invention.

[0050] Figure 2 It is a schematic diagram of the structure of the root growth observation container provided in Example 1 of the present invention.

[0051] Figure 3 It is a schematic diagram of the structure of the root identification research device provided in Example 2 of the present invention.

[0052] Figure 4It is a schematic diagram of the structure of the water outlet head described in an embodiment of the present invention. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0055] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0056] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0057] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0058] At present, there is a lack of dedicated equipment and methods for existing root growth and development research methods. In order to solve the above technical problems, the present invention proposes a method for identifying root stress in the seedling stage of fruit and vegetable crops, in which a low-cost simple device can be used to simulate the growth environment of fruit and vegetable crops in the seedling stage, and to conduct research on the identification of continuous or regular single or compound stress in the roots.

[0059] Example 1 Identification test of drought stress on roots of wild watermelon seedlings

[0060] Specifically, this embodiment provides a research method for identifying root water stress of wild watermelon seedlings, a vegetable and fruit crop, comprising the following steps:

[0061] (1) Assembly of the root identification research device

[0062] like Figure 1 and Figure 2 As shown, the root identification research device comprises a root growth observation container 10, a feeding module 30, a container support, a receiving tray and an observation device 20 that are matched and arranged;

[0063] The root growth observation container is a transparent rectangular flat barrel structure, including a first long side wall 11, a first short side wall 12, a second long side wall 13, a second short side wall 14 and a container bottom plate 15; the first short side wall 12 and the second short side wall 14 are arranged opposite to each other and have the same width, and the width W of the first short side wall 12 and the second short side wall 14 are 1 cm respectively; the first long side wall 11 and the second long side wall 13 are arranged opposite to each other and have the same width, and the width W of the first long side wall 11 and the second long side wall 13 are 50 cm respectively ; An opaque shielding layer 16 is detachably provided on the outer side of the first long side wall 11, a ruler is provided on the second long side wall, and the upper and lower sides of the second long side wall are respectively provided with a set of length and angle measuring rulers that can slide left and right and are connected to the upper and lower sides by clips 17, and an observation device is provided on the outer side of the second long side wall; A plurality of bottom holes are provided on the bottom plate of the container; An observation device 20 is provided on the outer side of the second long side wall; A plurality of bottom holes are provided on the bottom plate of the container, and a push-pull plate is provided to adjust the size and opening and closing of the bottom holes;

[0064] The feeding module 30 includes a hose 31 and a filter valve 32, a watering device 33, a check valve 34, a tee 35 and a water outlet 36 arranged in sequence on the hose 31; the water outlet end is arranged in the root growth observation container; the water outlet is arranged at one third of the height of the root growth observer; Figure 4As shown, the middle pipe of the water outlet head 36 is a spiral structure 361, and a plurality of spiral water outlet holes 362 are arranged on the spiral structure 361 of the water outlet head 36. The arrangement of the plurality of water outlet holes 362 and the spiral structure 361 can effectively slow down the water flow speed and reduce the impact force of water on the growth medium, so as to reduce the damage of the water flow to the surrounding roots and the formation of cavities in the growth medium;

[0065] The first long side wall, the first short side wall, the second long side wall, the second short side wall and the container bottom plate of the root growth observation container are assembled into a root growth observation container with a rectangular flat barrel structure; the filter valve 32, the watering device 33, the check valve 34, the three-way 35 and the water outlet 36 of the feeding module are connected to the hose in sequence, and the two water outlets are set in the root growth observation container; the observation device is placed outside the first long side wall;

[0066] A total of 12 root growth observation containers were installed, and a QR code was pasted on the corner of the second longest side wall of each root growth observation container to set the material name and research group;

[0067] (2) Filling the growing medium and assembling the automatic watering equipment

[0068] Fill the root growth observation container installed in step (1) with the wetted seedling medium, and the compactness is in accordance with the common seedling standard;

[0069] (4) Seedling cultivation and planting

[0070] Three holes were dug evenly at intervals above the gap filled with growth medium above the root growth observation container, and one soaked and germinated seed was sown in each hole, and then covered with growth medium; two wild watermelon rootstock varieties, Warrior and Wild Zhuang No. 1, were used in the experiment, both of which were commercially available seeds; each seed was sown in 6 containers, with a total of 18 plants, and a conventional water supply control and drought stress treatment were set;

[0071] (5) Plant growth management

[0072] The customized root growth observation container for seedling cultivation is placed on a plastic drain rack (container rack), with one container placed on each drain rack, and a collecting tray is placed at the bottom to collect excess water flowing out of the bottom of the root growth observation container; the overall 12 containers are arranged in a circle, and a bracket that can be remotely controlled to rotate according to the set frequency is installed in the middle. A camera, a far-infrared imager and a chlorophyll fluorescence imaging device are installed on the bracket, all of which can be connected to a mobile phone and a computer through the network for data and image collection; the chlorophyll fluorescence imaging device can take a 45° overhead shot of the aboveground part of the plant through a connecting rod, the camera takes a bird's-eye view of the aboveground part and a horizontal shot of the underground part, and the far-infrared imager takes a horizontal shot of the underground part; the plant growth environment temperature is set to 24°C for light, 16°C for darkness, 16h for light, and 8h for darkness; the light intensity is 20,000 lux; after the seeds emerge to 1 leaf and 1 heart, start processing and start the feeding module equipment; the feeding module of the treatment group is set to water once every 4 days, each time for 9 seconds, and the feeding module of the control group is set to water once every 3 days, each time for 18 seconds; treatment for 12 days;

[0073] (6) Observation of plant root growth and development

[0074] The camera at the base of the root growth observation container rotates once every 30 minutes to record the video, and takes a photo every 30° rotation; the far-infrared thermal imager and the chlorophyll fluorescence imaging system are the same; after the treatment, the container is opened to examine the aboveground and underground phenotypes and physiological performances such as MDA;

[0075] (7) Identification results

[0076] Finally, Ye Zhuang No. 1 was more drought-resistant than Yongshi. The degree of influence was calculated according to (treatment-control)*100 / control. The results showed that the aboveground fresh weight of Ye Zhuang No. 1 was 20% lower than that of Yongshi, the underground fresh weight was 26% lower, the chlorophyll content was 25% lower, the MDA of aboveground leaves was 28% lower, and the underground roots were 32% lower. The far-infrared temperature of the roots of the two material control and treatment groups showed obvious differences on the 5th and 7th days of treatment, respectively. The difference narrowed after each watering of the treatment group, and then continued to increase. The overall trend of expansion between the materials was wave-like. Among them, the expansion trend of the difference between the control and treatment of Yongshi continued to increase compared with Ye Zhuang No. 1. The photosynthetic fluorescence images showed that Yongshi showed stress symptoms 2 days earlier than Ye Zhuang No. 1, and the growth rate of stress symptoms was greater than that of Ye Zhuang No. 1.

[0077] Example 2 Identification test of water and fertilizer deficiency stress on pumpkin rootstock roots during seedling stage

[0078] In this example, Sizhuang No. 7 (Indian-Chinese hybrid pumpkin type) was selected and purchased from Ningbo Fengdeng Seed Technology Co., Ltd. to study the effects of water and fertilizer deficiency on the root growth and development of pumpkin rootstock seedlings.

[0079] Specifically, this embodiment provides a method for identifying water and fertilizer deficiency stress in the roots of pumpkin rootstocks at the seedling stage, comprising the following steps:

[0080] (1) Assembly of equipment for root identification research (such as Figure 3 (shown)

[0081] The root identification research device comprises a root growth observation container, a feeding module, a container support, a receiving tray and an observation device that are matched and arranged;

[0082] The root growth observation container is a transparent rectangular flat barrel structure, comprising a first long side wall, a first short side wall, a second long side wall, a second short side wall and a container bottom plate; the first short side wall and the second short side wall are arranged opposite to each other and have the same width, and the widths of the first short side wall and the second short side wall are 2.5 cm respectively; the first long side wall and the second long side wall are arranged opposite to each other and have the same width; an opaque shielding layer is detachably arranged on the outer side of the first long side wall, a ruler is arranged on the second long side wall, and an observation device is arranged on the outer side of the second long side wall; and four bottom holes are arranged on the container bottom plate;

[0083] The length and height of the first long side wall and the second long side wall of the root growth observation container are designed according to the width and length of the A4 size, respectively. The opaque shielding layer is pasted with yellow adhesive paper. The bottom hole is a 1 cm long hole. Each bottom hole is covered with 800 mesh gauze to prevent sand loss. A total of 12 root growth observation containers are installed. A QR code is pasted on the corner of the second long side wall of each root growth observation container, and the material name and research group are set.

[0084] The feeding module 30 includes a hose 31 and a filter valve 32, a watering device 33, a check valve 34, a tee 35, and a water outlet 36 arranged on the hose 31 in sequence; the end of the water outlet 36 is arranged in the root growth observation container; the water outlet 36 is arranged at one-third of the height of the root growth observer. The middle pipe of the water outlet 36 is a spiral structure 361, and the spiral structure 361 of the water outlet 36 is provided with a plurality of spiral water outlet holes 362. The arrangement of the plurality of water outlet holes 362 and the spiral structure 361 can effectively slow down the water flow speed and reduce the impact of water on the growth medium, so as to reduce the damage of the water flow to the surrounding roots and the formation of cavities in the growth medium.

[0085] Assemble the first long side wall, the first short side wall, the second long side wall, the second short side wall and the container bottom plate of the root growth observation container into a rectangular flat barrel-shaped root growth observation container; connect the filter valve 32, the watering device 33, the check valve 34, the tee 35 and the water outlet 36 of the feeding module to the hose in sequence, and set the water outlet in the root growth observation container; place the observation device on the outside of the first long side wall;

[0086] The feeding module comprises a hose and a filter valve, an automatic watering device, a check valve, a cross-way, a tee and a water outlet arranged on the hose in sequence; the water outlet end is arranged in the root growth observation container; the three subsequent water outlet ends of the cross-way are respectively connected to a tee, and the subsequent water outlet ends are each connected to two water outlets, and the two water outlets of each tee are connected to a root growth observation container; a total of 12 sets are assembled, of which 6 sets are used to connect to the water supply container and 6 sets are connected to the fertilizer supply container; each growth observation container is connected to 2 water supply and fertilizer supply outlets respectively;

[0087] Assemble the first long side wall, the first short side wall, the second long side wall, the second short side wall and the container bottom plate of the root growth observation container into a root growth observation container with a rectangular flat barrel structure; connect the filter valve, the watering device, the check valve, the tee and the water outlet of the feeding module to the hose in sequence, and set the two water outlets in the root growth observation container; place the observation device on the outside of the first long side wall;

[0088] (2) Filling the growing medium and connecting the automatic watering and detection equipment

[0089] The root growth observation container installed in step (1) is filled with sand; the filled growth observation container is placed on a plastic drain rack (container rack), one container is placed on each drain rack, and a collecting tray is placed at the bottom to collect excess water flowing out of the bottom of the root growth observation container; the 12 root growth observation containers are arranged in a straight line, and a guide rail 21 is installed at 40 cm parallel to the root growth observation container, and a bracket is provided on the bracket, and a bracket that can be remotely controlled to move back and forth at a set speed is installed on the bracket, and a camera and a chlorophyll fluorescence imaging device are installed on the bracket, which can be connected to a mobile phone and a computer through the network to collect data and images; the chlorophyll fluorescence imaging device takes a bird's-eye view of the aboveground part of the plant through a connecting rod, and the camera takes a bird's-eye view of the aboveground part and a horizontal view of the underground part;

[0090] (3) Nutrient solution preparation

[0091] The nutrient solution was prepared according to the method in the literature (Huang Yunping, Xing Nailin, Fu Yujing, et al. Effects of different types of rootstock grafting on cadmium content in watermelon fruit [J]. Shanghai Journal of Agriculture, 2020, 36(4):5);

[0092] (4) Seedling planting and water and fertilizer supply

[0093] Three holes were dug at an even interval on the upper part of the growth medium filled in the gap above the root growth observation container, and one soaked and germinated seed was sown in each hole, and then covered with the growth medium; a total of 36 plants were sown, and 4 treatments were set up, and the treatments began at the 1-leaf and 1-heart stage. Treatment A was an excessive water and fertilizer treatment, with water and fertilizer applied 3 times a day for 3 seconds each time; Treatment B was a normal water and fertilizer supply, with water and fertilizer applied 2 times a day for 3 seconds each time; Treatment C was an insufficient water and fertilizer supply, with water and fertilizer applied 2 times a day for 2 seconds each time; Treatment D was normal water and insufficient fertilizer, with water applied 2 times a day for 3 seconds each time and fertilizer applied 2 times a day for 2 seconds each time;

[0094] (6) Plant growth management

[0095] The experimental environment was set at 24℃ light, 16℃ dark, 16h light, 8h dark; light intensity was 20000lux; water and fertilizer supply in the early stage was carried out according to treatment 2, and water and fertilizer supply was divided into 4 treatments starting from the 1 leaf 1 heart stage; observation was carried out 10 days after treatment;

[0096] (7) Observation of plant growth and development

[0097] The camera on the bracket records the video once every 30 minutes, and takes a photo of each growth observation container once every hour; the chlorophyll fluorescence imaging system takes a photo of each container once every hour; after the treatment, the container is opened to examine the aboveground and underground phenotypes and physiological performances such as MDA;

[0098] (8) Results

[0099] With normal water and fertilizer supply as the control, the degree of influence was calculated according to (treatment-control)*100 / control; the fresh weight of the aboveground and underground parts of treatments CD decreased, with the aboveground fresh weight decreasing by 21.4% and 20.7%, respectively, and the underground fresh weight decreasing by 14.3% and 15.6%, respectively; the fresh weight of the aboveground and underground parts of treatment A increased, with the aboveground and underground parts increasing by 8.2% and 4.7%, respectively; the fluorescence images showed that the stress began to appear 3 days after the start of the treatment, and then the differences between different treatments continued to increase in waves, among which treatment C was the most serious, followed by treatment A in the early stage, and treatment D after the middle stage.

[0100] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0101] 1. The present invention aims at the defects of existing research methods for identifying root stress of fruit and vegetable crops. By using a low-cost simple device (root growth observation container and feeding module), the actual growth environment of fruit and vegetable crops can be simulated to conduct remote and automated identification of various single or combined stresses such as water, fertilizer, and medicine. The continuous growth and development observation research of root stress response can be carried out, which is used for cultivation technology research, germplasm resource evaluation and identification, variety breeding, physiological and biochemical research; and can be used for making specimens or taking root samples.

[0102] 2. The root growth observation container used in the research method of the present invention can better realize the comprehensive observation of the root growth and development of the fruit and vegetable crops planted therein through the transparent side and the container gap of 1-3 cm, and there is no need to damage the roots; at the same time, the optimal restoration state of the root growth without light can be achieved by disassembling and assembling the opaque shielding layer on the opaque side (the outer side of the first long side wall is detachably provided with an opaque shielding layer), and the opaque shielding layer can be removed at any time for observation and recording, as well as comparison with the transparent state on the other side; the root growth observation container can be filled with various growth media, and the effects of various growth media and growth medium compactness and other conditions on the root growth and development of fruit and vegetable crops in the seedling stage can be studied, as well as the synergistic interaction between the growth medium and the stress environment such as water, fertilizer and medicine; the microorganisms and pathogens in the growth medium can be designed to study and observe their effects on root development, and observe and analyze the appearance and physiological manifestations of the whole process of root diseases and insect pests.

[0103] 3. The research method for identifying root stress of fruit and vegetable crops at the seedling stage of the present invention can be used for studying the interaction between species or between varieties within a species by planting two or more different crops or different varieties in a growth observation container, and continuous observation and research on the seedling interaction between species can be carried out through the root growth observation container, which is of great value for real-time observation and research of roots.

[0104] 4. The research method for identifying root stress of fruit and vegetable crops at the seedling stage of the present invention can obtain complete root specimens at different stress stages through the combination and disassembly of growth containers, which can be used for teaching, popular science, and research on root development, and has good practicality and economic promotion value.

[0105] 5. The research method for identifying root stress of fruit and vegetable crops in the seedling stage of the present invention realizes high-throughput root stress identification through remote and automated addition of water, fertilizer, and medicine, combined with network equipment, connection of automated guide rails and detection, photography, and video equipment, which can save a lot of manpower, improve accuracy, and reduce human errors.

[0106] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for identifying root stress of fruit and vegetable crops at the seedling stage, characterized in that: The steps include: (1) Assembly of the root identification research device The root identification research device comprises a root growth observation container, a feeding module, a container support, a receiving tray and an observation device that are matched and arranged; The root growth observation container is a transparent rectangular flat barrel structure, comprising a first long side wall, a first short side wall, a second long side wall, a second short side wall and a container bottom plate; the first short side wall and the second short side wall are arranged opposite to each other and have the same width, and the widths of the first short side wall and the second short side wall are 1-3 cm respectively; The first long side wall and the second long side wall are arranged opposite to each other and have the same width, and the widths of the first long side wall and the second long side wall are 10-80 cm respectively; an opaque shielding layer is detachably arranged on the outer side of the first long side wall, a ruler is arranged on the second long side wall, and the upper and lower sides of the second long side wall are respectively provided with a set of length and angle measuring rulers that can slide left and right and are connected to the upper and lower sides by clips, and an observation device is arranged on the outer side of the second long side wall; a plurality of bottom holes are arranged on the bottom plate of the container; The feeding module comprises a hose and a filter valve, a watering device, a check valve, a tee and a water outlet arranged on the hose in sequence; the water outlet end is arranged in the root growth observation container; Assembling the first long side wall, the first short side wall, the second long side wall, the second short side wall and the container bottom plate of the root growth observation container into a root growth observation container with a rectangular flat barrel structure; Connect the filter valve, watering device, check valve, tee and water outlet of the feeding module to the hose in sequence, and place the water outlet in the root growth observer; place the observation device on the outside of the first long side wall; (2) Growth medium filling Filling the root growth observation container installed in step (1) with growth medium; (3) Seedling cultivation and planting After the growth medium is filled in step (2), a hole is dug on the upper surface of the growth medium in the root growth observation container, and the seeds of the fruit and vegetable crops used for stress identification are sown with the radicle facing downward, and then covered with the growth medium; (4) Plant growth management The root growth observation container is placed on the container support, and the receiving tray is arranged below the container support at a position corresponding to the bottom hole; water is added to the watering device end of the feeding module, and stress factors are added according to the needs of the stress identification research; the water outlet of the feeding module is inserted into the growth medium, and the water outlet is arranged around the seeds of fruit and vegetable crops or between two seeds; the stress factors of water, fertilizer, and bacteria are added and the growth management is carried out through the feeding module; (5) Observation of plant roots and overall growth and development The plant roots are photographed, recorded and observed by the observation device arranged on the outside of the second long side wall; and the opaque shielding layer on the outside of the first long side wall is opened for observation and recording, and the difference in root development exposed to external light and that not exposed to external light can be compared; by observing and recording the photographic results and data of root stress of fruit and vegetable crops, root stress of fruit and vegetable crops can be identified.

2. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: In step (1): The root growth observation container is prepared by using a transparent plastic plate.

3. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: The bottom hole is a hole with a diameter of 1 cm; The root growth observation container also includes a gauze mesh, which is adhered and covered on the inner side of the container bottom plate and matches the bottom hole.

4. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: The opaque shielding layer is at least one of opaque paper, cloth or board.

5. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: The water outlet is arranged at one third of the height of the root growth observer; The middle pipe of the water outlet head is a spiral structure, and a plurality of spiral water outlet holes are arranged on the spiral structure of the water outlet head.

6. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: The observation device includes at least one of devices for video recording, photographing or observation. When there are many observation devices, an automatic guide rail can be installed to perform cyclical timed shooting and monitoring. It can also be combined with network equipment for remote control, inspection, information acquisition and change of research methods.

7. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: In step (2): The growth medium is at least one of a seedling medium, sand, gravel or farmland soil; the growth medium used is added with corresponding stress factors according to the needs of the root adversity stress experiment, and the stress factors include at least one of stress factors such as high salt, high alkali or water and fertilizer deficiency.

8. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: In step (3): The vegetable and fruit crop seeds are soaked and germinated before sowing; During the sowing process, seeds of two or more different crops can be sown to study the mutual influence relationship between the roots of the crops during the process of adverse environment stress.

9. The method for identifying root stress of fruit and vegetable crops at the seedling stage according to claim 1, characterized in that: In step (4): The stress factor is at least one of high salt, high alkali or water and fertilizer deficiency stress factors; if the stress factor needs to be mixed with water for irrigation, it is added to the watering device together with water for mixing and then added; if the stress factor does not need to be mixed with water for irrigation, the stress factor can be applied alone; The growth management specifically involves processing water, nutrition, medicine, light, and temperature according to crop growth rules or research purposes. The required water, fertilizer, and medicine are applied through the water outlet; light and temperature are controlled through the growth environment.

10. The method for identifying root stress of fruit and vegetable crops at seedling stage according to claim 1, characterized in that: In step (5): The root stress identification is carried out by examining the phenotype, physiological and biochemical indicators of the above-ground and underground roots of the plants, combined with image data obtained by taking photos and imaging during the growth process, to identify the root stress of fruit and vegetable crops.

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