A method for measuring the quality of rice machine-transplanted seedlings

Abstract

The present invention discloses a method for measuring the quality of mechanically transplanted rice seedlings. The quality level of the seedlings is measured by the ratio of plant height to leaf age. K = (0.9<supgt;(n‑2)< / supgt;)*h / N, (2≤N≤5.5, n = ⌊N⌋), where h represents the plant height of the seedlings, N represents the leaf age of the seedlings, (0.9<supgt;(n‑2)< / supgt>) is the K-value correction coefficient, n is the value obtained by rounding N downwards, the reasonable range of the K-value is 2.7-4.2, the larger the K-value, the weaker the quality of the seedlings, and the smaller the K-value, the higher the quality of the seedlings. The present invention can quickly and immediately measure the quality of the seedlings and classify the quality; in addition, it can compare the quality of the seedlings horizontally and vertically through this index, and has wide applications.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural cultivation, and specifically relates to a method for measuring the quality of mechanically transplanted rice seedlings. Technical Background

[0002] With the vigorous development of cultivation techniques and supporting machinery, as well as the implementation of the national land transfer system, the scale of farms is expanding day by day and agricultural service organizations are emerging and growing, which has promoted the large-scale and mechanized planting of rice. For the mechanized planting of rice, the large-scale cultivation of mechanically transplanted seedlings requires strict population control to make their quality meet the predetermined indicators and achieve the goal of efficiently and safely cultivating high-quality mechanically transplanted seedlings.

[0003] At present, the quality indicators for seedling populations are mainly divided into two types: one is objective evaluation, mainly used in scientific research work. By sampling and examining various indicators of seedlings, a series of trait indicators are analyzed by laboratory means, and the quality of seedlings is comprehensively evaluated through an index set. It requires certain professional knowledge and professional equipment. Although the evaluation results are accurate and reliable, they require a certain amount of analysis time and have time lag, making it difficult to provide immediate guidance for production practice. The other is subjective evaluation, mainly used in production practice activities to provide opinions and basis for field management. The evaluation work is carried out by the intuitive observation of workers in the field (auxiliary with some simple indicators such as leaf age, plant height, root bundling situation, leaf color, etc.). It depends on the professional level and experience of the evaluator, and the standard is highly subjective. Different results are often obtained due to subjective differences among evaluators, making the evaluation results uncertain or unreliable, which brings risks to the seedling management work. Neither of these two methods has an objective and single index that can quickly, conveniently, immediately, and objectively evaluate and compare the quality of seedlings. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a method for measuring the quality of mechanically transplanted rice seedlings, which can quickly and immediately measure the quality of seedlings and classify the quality; in addition, it can horizontally and vertically compare the quality of seedlings through this index.

[0005] The present invention is realized through the following technical solutions:

[0006] A method for measuring the quality of mechanically transplanted rice seedlings,

[0007] using the ratio of plant height to leaf age to measure the quality level of seedlings, K = (0.9 （n-2） ) * h / N, (2 ≤ N ≤ 5.5, n = ⌊N⌋), where h represents the plant height of the seedlings, N represents the leaf age of the seedlings, (0.9 （n-2） ) is the K-value correction coefficient, and n is the value obtained by rounding N downwards, ， The reasonable range of the K value is 2.7 - 4.2. The larger the K value, the weaker the quality of the seedlings, and the smaller the K value, the higher the quality of the seedlings.

[0008] A further improved technical solution of the present invention is that according to the value of K, the seedling quality is divided into 5 levels:

[0009] K1 K2 K3 K4 K5 K-value range ＜2.7 2.7-3.2 3.2-3.7 3.7-4.2 ＞4.2 Quality evaluation Stunted seedlings Strong seedlings Normal seedlings Weak seedlings Extra-long seedlings

[0010] The order of seedling quality from high to low is: K2 > K3 > K4 > (K1, K5).

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] I. Immediacy: It can quickly and immediately obtain indicators, judge and compare the seedling quality, which can be measured and obtained in the field immediately, quickly judge the seedling quality, take corresponding measures in time, avoid lagging treatment, and can be well used to guide production activities and improve the seedling raising technology.

[0013] II. Simplicity: Only the plant height and leaf age of rice seedlings need to be measured and converted by borrowing a formula, without the need for professional knowledge and professional equipment, and it does not consume a lot of time; nor will it produce subjective deviation.

[0014] III. Versatility: It can be used for horizontal and vertical comparison of seedlings, and is applicable to seedlings implemented at different times, different locations or different subjects. It is suitable for summarizing cultivation measures in production and obtaining a set of suitable cultivation technology systems. Description of the Drawings

[0015] Figure 1 It is a correlation linear diagram of the plant height and leaf age of rice seedlings.

[0016] Figure 2 It is a dynamic change diagram of the ratio of plant height to leaf age of seedlings under the same treatment. Specific Embodiment

[0017] I. Proposal of the index "ratio of plant height to leaf age"

[0018] According to the synchronous growth law of rice leaves, there is a close connection and specific law between the elongation of leaves and the emergence of new leaves, which is intuitively manifested in the relationship between plant height and leaf age. By analyzing the relationship between the two indexes of plant height and leaf age, the index "ratio of plant height to leaf age" is proposed and used to timely, accurately and reliably evaluate the seedling quality and growth situation, and classify the seedling quality.

[0019] Using Lianjing 9 as the rice variety for the experiment, wet seedling raising was carried out by open-air soft disk machine transplanting (the soft disk specification is 58 cm x 28 cm). Three different sowing density treatments were set, and the seeding rates of A90, A120, and A150 were 90 g / disk, 120 g / disk, and 150 g / disk respectively. The fertilization level, management method, and others were kept consistent. Sowing was carried out on June 5th, and the film was removed on June 14th. Samples were taken from each treatment at 13 d, 17 d, 21 d, 25 d, and 29 d after sowing, and various traits of the seedlings (such as plant height, leaf age, stem base width, root growth conditions, etc.) were investigated, and root activity, nutrient content, etc. were measured.

[0020] 1. Correlation between plant height and leaf age

[0021] Analyze the correlation between plant height and leaf age. For example, Figure 1 , the correlation coefficients R between plant height and leaf age of the three treatments A90, A120, and A150 are 0.984, 0.953, and 0.990 respectively. The relationship between plant height and leaf age is close, and there is a significant positive correlation. Under the same growth environment (experimental treatment, management measures, climatic conditions, etc.), the larger the leaf age, the corresponding larger the plant height; conversely, when the plant height increases, the leaf age also increases accordingly.

[0022] From Figure 1 , it can be seen that because there is a close linear positive correlation between plant height and leaf age, we can assume that for the same seedling, at a certain growth time point, the ratio of its plant height to leaf age is constant, and the ratio between the two can be used to evaluate the growth state (quality) of this seedling. Considering the convenience of numerical comparison, the ratio of plant height (h) to leaf age (N) is used to represent the plant height to leaf age ratio, denoted by the letter K, to measure and compare the seedling quality. Since the seedling quality during the normal growth period of the seedbed is being investigated, seedlings with a relatively small seedling age (N < 2) and over-aged stages (N > 5.5) are not within the scope of this discussion.

[0023] K = h / N (2 ≤ N ≤ 5.5)

[0024] For machine-transplanted seedlings, the strong seedlings we need to cultivate should be short and strong seedlings (that is, at the same leaf age, seedlings with a shorter plant height, thicker stems, and well-developed roots), which have the advantages of being conducive to transplanting, having tough stems, strong resistance to transplanting injury, and strong root activity. The K value can be simply understood as the increase in plant height of the seedling for each additional leaf growth. Therefore, the smaller the K value, the smaller the corresponding plant height of the seedling, indicating that the quality of the seedling is higher. However, for old and stunted seedlings (stunted and not growing), this index will be inaccurate.

[0025] 2. Correction of the K value ("plant height to leaf age ratio")

[0026] The processing analysis involves sampling and measuring various traits of the rice seedlings every four days. To eliminate the influence of weather on the growth of rice seedlings, the growth time of the rice seedlings is converted into effective accumulated temperature for representation. Figure 2 It shows the dynamic changes in the ratio of plant height to leaf age of the rice seedlings under the same treatment. During the seedbed growth period of the rice seedlings, the change range of the ratio of plant height to leaf age is generally between 2.5 and 5.5. For rice seedlings with similar qualities (consistent growth), the ratio of plant height to leaf age at the same leaf age stage is basically constant. However, from the perspective of a single treatment, the ratio of plant height to leaf age gradually increases during the growth period. The reason why the K value of rice seedlings with the same quality increases with the increase of seedling age is that under the condition of unchanged seedling quality, the rate of change of seedling age and the rate of change of plant height are not in the same proportion, but the rate of change of plant height is higher than the rate of change of leaf age.

[0027] If the K value can be adjusted to the same leaf age stage, the K value can be effectively corrected. When examining rice seedlings with the same quality, the K values at the 2-leaf stage, 3-leaf stage, and 4-leaf stage of the rice seedlings are respectively denoted as K2, K3, and K4. After statistics, it is found that the ratios of K3 / K2 and K4 / K3 are basically stable around 1.11. That is, on the premise of unchanged seedling quality, for each increase in one seedling age, the K value correspondingly becomes 1.11 times larger (approximate value). By uniformly adjusting the K values at other leaf age stages to the K value at the 2-leaf stage, we can obtain:

[0028] K = (0.9 （n-2） ) * h / N, (2 ≤ N ≤ 5.5, n = ⌊N⌋),

[0029] where h represents the plant height of the rice seedlings, N represents the leaf age of the rice seedlings, and (0.9 （n-2） ) is the K value correction coefficient (used to correct the non-linear relationship between leaf age and plant height. This coefficient is an empirical coefficient, n is the value obtained by rounding down N, and (n - 2) represents the corresponding adjustment of this coefficient with the increase of leaf age).

[0030] 3. Use of the K value

[0031] According to the size of the K value, the seedling quality of the rice seedlings is divided into 5 levels ("K value seedling quality table"):

[0032] Table 1 K value seedling quality table

[0033] K1 K2 K3 K4 K5 K-value range ＜2.7 2.7-3.2 3.2-3.7 3.7-4.2 ＞4.2 Quality evaluation Stunted seedlings Strong seedlings Normal seedlings Weak seedlings Extra-long seedlings

[0034] When the K value is within the reasonable range (2.7 - 4.2), the smaller the K value, the higher the seedling quality; when the K value is not within the reasonable range, the seedling quality is low and not involved in the comparison; the order of seedling quality from high to low is: K2 > K3 > K4 > (K1, K5)

[0035] II. Verification of the K value of the index "ratio of plant height to leaf age"

[0036] 1. Correlation between plant height and leaf age ratio (K) and other traits

[0037] For seedlings at the same leaf age stage, from the perspective of individual traits, the larger the basal stem width, the higher the seedling quality, and the same trend is also shown in indicators such as root-shoot ratio, root activity, and nitrogen content. Since the basal stem width increases continuously with growth, "basal stem width / N" is used for simple processing to represent the increase in basal stem width when increasing one leaf age, and the root-shoot ratio represents the ratio of dry weight of roots to above-ground parts.

[0038] It can be concluded from Table 2 that the K value has a correlation with several traits, and shows a negative correlation, that is, the smaller the K value, the better the performance of several related traits and the better the seedling quality, indicating that the K value can be used to evaluate the seedling quality.

[0039] Table 2 Correlation between K value and other traits

[0040] <![CDATA[R 2 > Stem base width / N Root-shoot ratio Root activity Nitrogen content <![CDATA[K A90 > 0.8262 0.8658 0.9138 0.8241 <![CDATA[K A120 > 0.8165 0.8535 0.9322 0.8356 <![CDATA[K A150 > 0.8339 0.8389 0.9286 0.8472

[0041] 2. Practical verification

[0042] 2.1 Take the seedlings grown in the seedbed, and according to the empirical judgment combined with some basic traits of the seedlings (plant height, leaf age, basal stem width, root system, leaf color, etc.), divide the taken seedlings into 3 categories, denoted as Class I seedlings, Class II seedlings, and Class III seedlings. Randomly select 50 plants from each of these three categories of seedlings to examine their K values, denoted as K1, K2, and K3. It can be seen from Table 3 that the evaluation of seedling quality by the K value is basically consistent with the empirical evaluation.

[0043] Table 3 Quality evaluation of seedlings in three categories

[0044] Empirical classification Seedling description Empirical evaluation K-value K-value evaluation Evaluation consistency Type I seedlings Seedling age: 20 days, leaf age: 4.0 - 4.2, plant height: about 15 cm, 4 leaves are basically green, the first leaf is slightly yellow, the leaves are thick, wide and dark green, the stem is thick, flat, and the roots are thick, white and well-knotted. Strong seedlings K1=2.86 Strong seedlings Consistent Type II seedlings Seedling age: 20 days, leaf age: 3.7 - 4.0, plant height: about 14 cm, the leaves are basically green, the leaves are dark green, the stem is relatively strong, and the roots are thick, white and well-knotted. Normal seedlings K2=3.34 Normal seedlings Consistent Type III seedlings Seedling age: 20 days, leaf age: 2.5 - 3.1, plant height: about 10 - 13 cm, the leaves are slender and lighter in color, the stem is slender and weak, the roots are short and dark brown, and there is basically no knotting ability. Weak and small seedlings K3=3.93 Weak seedlings Consistent

[0045] 2.2 Select 5 seedling beds with different qualities, and mark them as No. 1 field, No. 2 field, No. 3 field, No. 4 field, and No. 5 field respectively. The specific situations of the fields are as follows:

[0046] Table 4 Description of the situations of five fields

[0047] Field Seedling raising method Rice variety Seeding rate (g / tray) Seedling age Leaf age Field No. 1 Open-air soft disk seedling raising Huai Rice 5 140g 19d 3.7-3.9 Field No. 2 Open-air soft disk seedling raising Nanjing 9108 140g 22d 4.1-4.3 Field No. 3 Hard disk darkening seedling raising Huai Rice 5 125g 16d 3.3-3.5 Field No. 4 Hard disk darkening seedling raising Nanjing 9108 120g 16d 3.3-3.5 Field No. 5 Hard disk darkening seedling raising Huai Rice 5 125g 14d 2.8-3.1

[0048] Invite a jury composed of 2 rice seedling experts and 3 practitioners with rich seedling raising experience, a total of 5 people, to evaluate the seedling quality of these 5 fields. At the same time, take 50 representative and uniformly growing seedlings from each of these 5 fields to examine their K values.

[0049] The jury reached the following conclusions:

[0050] No. 1 field seedlings: The plant height and leaf age are relatively appropriate, and they are in the right planting period. The leaves are wide and dark green, the stems are of moderate thickness, the root system is well developed, and the coiling ability is good. They are high-quality seedlings.

[0051] Seedlings in Field No. 2: The plant height is relatively high, which has a certain impact on field planting operations. The leaves are wide and long with good leaf color, but the first leaf in the seedling tray is seriously dead and yellow. The stems are thick but not tough enough. The root system is well developed and the coiling ability is good. The quality is acceptable but it is over the age limit.

[0052] No. 3 field seedlings: The plant shape is compact and upright, the leaves are wide and dark green, the stems are strong, the root system is well-developed, the roots are numerous and thick and white, and the coiling ability is good. It is a high-quality seedling.

[0053] Seedlings in Field No. 4: The performance is basically the same as that of the seedlings in Field No. 3.

[0054] Seedlings in field No. 5: The plants are thin, the stems are not tough enough, the leaves are light yellow, and the roots are dark brown. They are seedlings of poor quality.

[0055] The ranking of comprehensive quality is: No. 3, No. 4 > No. 1 > No. 2 > No. 5

[0056] Compared with the "K value seedling quality table", the K value performance is shown in Table 5, and the seedling quality ranking is: No. 3> No. 4> No. 1> No. 2> No. 5, among which No. 3 and No. 4 are not much different. This conclusion is consistent with the conclusion given by the judging panel.

[0057] Table 5 K values ​​and quality evaluation of five plots

[0058] Field Plant height (cm) Leaf age K-value Quality evaluation Field No. 1 15.3 3.86 3.57 Normal seedlings Field No. 2 20.6 4.22 3.95 Weak seedlings, over-aged seedlings Field No. 3 12.6 3.42 3.31 Normal seedlings, close to strong seedlings Field No. 4 12.5 3.48 3.23 Normal seedlings, close to strong seedlings Field No. 5 12.2 2.87 4.25 Extra-long seedlings

[0059] Conclusion

[0060] Combined with the above analysis, the K value is objective and accurate and can be used to evaluate the quality of seedlings.

[0061] 4. The effective application scope of the present invention:

[0062] 1. Used for immediate evaluation of seedling quality: For farm or large-scale planting practitioners, it is necessary to know the growth status of seedlings in a timely manner, such as whether they are strong and whether the plant height is appropriate, so as to guide the production activities of machine transplanting and cultivation in a timely manner. If laboratory analysis methods are used, the process is not only cumbersome, but also takes a lot of time, which is easy to cause delays in the implementation of countermeasures; if subjective judgment methods are adopted, it is heavily dependent on the judge and his experience, and it is easy for judges to disagree. The plant height to leaf age ratio (K) can be obtained immediately on site, quickly judge the quality of seedlings, and take countermeasures in time.

[0063] 2. For the horizontal and vertical comparison of the quality of machine-transplanted rice seedlings: For scientific researchers, a batch of experimental treatments are designed, such as the fertilizer ratio experiment during seedling cultivation. According to different fertilizer formulas, they are divided into treatments A1, A2, A3, etc. By collecting the plant height to leaf age ratio (K) of A1, A2, A3, etc. at different times a1, a2, a3, etc., the respective quality change trends of A1, A2, A3, etc. can be obtained, and the quality differences between A1, A2, A3, etc. can also be compared. In addition, others have also conducted fertilizer ratio experiments, and the treatments are B1, B2, B3, etc. The value of the plant height to leaf age ratio (K) can be obtained based on their plant height and leaf age data, and the quality of the seedlings treated by oneself can be compared with it to compare the advantages and disadvantages of one's own method.

[0064] 3. For tracking the quality changes of the same rice seedlings at different times: For scientific researchers and large-scale producers (such as farms, large growers, etc.), it is necessary to track the quality changes of rice seedlings. For example, a certain farm centrally cultivates a certain area of machine-transplanted rice seedlings during the production season, and the plant height to leaf age ratio (K) of the rice seedlings can be recorded at regular intervals to know the quality change trend of the rice seedlings. When the K value changes abnormally, analyze the reasons in time and take corresponding measures to keep the growth of the rice seedlings on the right track. And through the change trend of the K value of the rice seedlings, summarize the cultivation measures in production and obtain a suitable cultivation technology system.

[0065] 4. For the effect evaluation of machine-transplanted rice seedling raising services: The machine-transplanted rice seedling raising service organization A signs a machine-transplanted rice seedling cultivation contract with its service object B. The two parties agree that A will provide qualified rice seedlings on the specified date, and the measurement index is that the plant height to leaf age ratio (K) is within a certain range. B needs to pay the corresponding rice seedling price a. When delivering the goods, B judges whether the rice seedlings provided by A are qualified according to the actual K value of the rice seedlings. If they are qualified, the two parties will fulfill the contract smoothly. If they are unqualified, the two parties will negotiate separately. In addition, A can divide the quality of the rice seedlings into different grades X1, X2, X3... according to the K value, corresponding to different prices a1, a2, a3... and put them on the market.

Claims

1. A method for measuring the quality of mechanically transplanted rice seedlings, characterized in that: Use the ratio of plant height to leaf age to measure the quality level of rice seedlings, \(K=(0.9 （n-2） \)*h / N, (2≤N≤5.5, n = ⌊N⌋), where h represents the plant height of the rice seedlings, N represents the leaf age of the rice seedlings, (0.9 （n -2） \) is the correction coefficient of the K value, n is the value obtained by rounding N downwards. According to the size of the K value, the quality of the rice seedlings is divided into 5 levels. The reasonable range of the K value is 2.7 - 4.

2. The larger the K value, the weaker the quality of the rice seedlings, and the smaller the K value, the higher the quality of the rice seedlings; the K values and corresponding levels are as follows: The order of seedling quality from high to low is: K2 > K3 > K4 > (K1, K5).

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