CN119285392A

CN119285392A - A method for preventing and controlling late blight of potatoes planted on red soil sloping farmland

Info

Publication number: CN119285392A
Application number: CN202411835701.7A
Authority: CN
Inventors: 李雨频; 李朝丽; 查丽霞; 邓立人; 郑毅; 杨丽
Original assignee: Yunnan Agricultural University
Current assignee: Yunnan Agricultural University
Priority date: 2024-12-13
Filing date: 2024-12-13
Publication date: 2025-01-10

Abstract

The invention provides a method for preventing and controlling late blight of potato planted in red soil slope farmland, wherein the fertilizer comprises urea, calcium superphosphate and potassium sulfate, and the mass ratio of the urea to the calcium superphosphate to the potassium sulfate is 15:12-13.5:16.5. The method uses phosphite to replace pesticide completely or partially during cultivation to prevent and treat potato late blight. Compared with the conventional fertilizer application in the field, the optimized fertilizer reduces the usage amount of the fertilizer without obviously affecting the content of soil nutrients and the accumulation of plant nutrients. In addition, phosphite is used for replacing pesticides, and has a prevention and treatment effect on potato late blight. The method for preventing and treating late blight by using the fertilizer and phosphite with optimized formula has important significance for good development of potato industry.

Description

Late blight control method for planting potatoes in red soil slope farmland

Technical Field

The invention belongs to the technical field of crop planting, and particularly relates to a late blight control method for planting potatoes in red soil slope farmland.

Background

Potato (Solanum tuberosum) originates from annual herbs of the genus solanum of the family solanaceae in the mountain range of south america, is the fourth largest food crop worldwide, and the first place in China. Research on potatoes has not only been concerned with the efficiency and yield of agricultural production, but has also been closely related to global food supply and environmental sustainability. The potato research is not only related to the efficiency and stability of agricultural production, but also is closely related to grain supply, environmental protection and scientific innovation, and has important social and economic significance. The potato is a main food source in many areas, the optimized production directly affects the food supply and human nutrition for food safety, the potato is an important commercial crop for economic development, helps farmers to increase income and promote agricultural economic development, and reduces pesticide use and improves drought resistance and disease resistance for environmental protection, thereby being beneficial to protecting ecological environment and soil health.

Fertilization is an effective means for improving potato yield, and nitrogen, phosphorus and potassium required for potato growth are obtained from soil except for a small part, and are mainly provided by fertilization, so that when soil nutrients are insufficient, the soil nutrients need to be supplemented by fertilization. Due to the outstanding problems of unreasonable fertilizer formula, imbalance of nitrogen, phosphorus and potassium proportions, insufficient application of organic fertilizers and the like of potato fertilization, imbalance of nitrogen, phosphorus and potassium nutrient proportions in soil nutrients, reduced content of soil organic matters, hardening and low fertilizer utilization rate, the fertilization cost is increased and the quality is poor. The optimized fertilization is to seek reasonable nitrogen, phosphorus and potassium proportion, and improve the physicochemical property of the soil while not affecting the soil nutrient, thereby achieving the effect of increasing the yield.

Late blight of potato is caused by phytophthora infestans, is highly destructive, can cause 100% yield loss, and causes serious harm to potato planting in the global scope. The rapid spread and high degree of destructiveness of this disease makes it one of the major challenges in agricultural production. Late blight is transmitted mainly through spores, humid and cool climatic conditions provide the most ideal environment for its transmission, and rain and wind can transmit spores to healthy plants, causing new infections. Disease symptoms of late blight appear first on potato leaves, appearing as water-soaked spots and black mold patches. As the disease progresses, the plant leaves gradually wither and decay, and the stems and tubers may also become infected, resulting in reduced yields.

For a long time, scientific researchers develop intensive researches on pathogenic bacteria characteristics, propagation rules and prevention measures. At present, the biological characteristics of pathogenic bacteria of late blight, disease resistance of host plants, disease resistance mechanism and the like are well known. From the aspect of action mechanism, the action mechanism of the existing medicament is relatively concentrated on the aspects of interference or obstruction of mitochondrial respiration, damage of a membrane structure, influence of substance metabolism and synthesis, inhibition of related functional enzymes and the like, and most of the medicaments have high selectivity, the action target point is single, but due to the obvious physiological differentiation and rapid genetic variation characteristics of oomycetes, the single-target fungicide has serious resistance problems due to easy resistance generation, such as pyraclostrobin, cyazofamid, metalaxyl and the like, and novel medicaments such as fluorothiazole pyraclostrobin, fluoroether bacteria amide and the like have high resistance risks, so that the medicaments for developing the novel action mechanism are hot spots for preventing and treating potato late blight in the future. In addition, the adoption of the mode of mixing agent to improve the control effect and delay the occurrence of resistance is also a practical and effective means. Therefore, the search for a reasonably effective new compounding regimen is another research hotspot for future control of potato diseases. Meanwhile, as the biological source medicaments such as eugenol, shenqimycin and the like have better control effect, and most of the biological source medicaments have the advantages of green safety, low toxicity, difficult generation of drug resistance and the like, the biological source medicaments at the present stage have fewer varieties, so that the search for developing new biological source medicaments is also an important research direction for controlling potato late blight in the future.

Disclosure of Invention

The invention aims to provide a method for preventing and controlling late blight of potato planted in red soil slope farmland, so as to solve the problem of epidemic late blight caused by excessive fertilization in the potato planting process in slope farmland.

The invention firstly provides a fertilizer for planting potatoes in red soil slope farmland, which comprises urea, calcium superphosphate and potassium sulfate in a mass ratio of 15:12-13.5:16.5;

As a specific description of the embodiment, the fertilizer is characterized in that the mass ratio of urea, superphosphate and potassium sulfate is 15:13.5:16.5 or 15:12:16.5;

in a further aspect, the invention provides a method for planting potatoes in red soil slope farmland, wherein the method comprises the steps of applying the fertilizer during the planting process;

The method is to apply 1200-1500Kg of fertilizer per hectare, wherein two thirds of the fertilizer is applied as base fertilizer and one third of the fertilizer is applied as topdressing;

Wherein the topdressing is carried out when the potatoes enter the tuber expansion period.

Still further, the method is to use phosphite to replace pesticide in whole or in part during planting to control potato late blight.

As a specific description of the examples, the treatment was carried out by a blade spraying method in which the phosphite was used at a concentration of 2.5mM.

Compared with the conventional fertilizer application in the field, the optimized fertilizer reduces the usage amount of the fertilizer without obviously affecting the content of soil nutrients and the accumulation of plant nutrients. In addition, phosphite is used for replacing pesticides, and has a prevention and treatment effect on potato late blight. The method for preventing and treating late blight by using the fertilizer and phosphite with optimized formula has important significance for good development of potato industry.

Drawings

FIG. 1 shows the total phosphorus content of soil in each growth period of potatoes, wherein CK (no fertilization+pesticide), T1 (local conventional fertilization: 15-15-15+pesticide), T2 (optimized fertilization 1 (15-13.5-16.5+pesticide), T3 (optimized fertilization 2 (15-12-16.5+pesticide), T4 (local conventional fertilization+phosphite), T5 (optimized fertilization 1+phosphite), T6 (optimized fertilization 2+phosphite). Different lowercase letters a, b and c represent the same growth period, differences among different treatments are remarkable (P < 0.05), and the upper-case A, B, C letters represent tuber forming period, tuber swelling period and starch accumulating period respectively, and the reference numerals in each figure are consistent with those in FIG. 1.

FIG. 2 is a graph showing the total potassium content of potatoes in each growth period;

FIG. 3 is a graph showing the organic matter content of soil in each growth and nutrition period of potatoes;

FIG. 4 shows the alkaline hydrolysis nitrogen content of soil in each growth period of potatoes;

FIG. 5 shows the quick-acting phosphorus content of soil in each growth period of potatoes;

FIG. 6 shows the content of quick-acting potassium in each growth period of potato;

FIG. 7 is a graph of potato plant total content, wherein FIG. A, B, C shows a graph of plant total nitrogen content, plant total phosphorus content, and plant total potassium content, respectively.

Detailed Description

According to the invention, under the condition that the consumption of different fertilizers of potatoes is reduced, the influence of phosphite to the occurrence and development of potato nutrients, yield and late blight of red soil slope farmland is studied, and the phosphite can be determined to be used as a green bactericide for preventing and controlling potato late blight. And a novel plant phosphorus and weed control system is established, so that the practical problems in agricultural production such as excessive application of phosphate fertilizer and herbicide, low utilization rate of soil phosphorus, super weeds and the like can be simultaneously solved, and weight losing and synergy can be effectively realized.

The hillside cultivated land refers to dry land with poor flatness, outstanding water and fertilizer running and low crop yield, which is distributed on the hillside. The concept of the main characteristic "sloping field" generally refers to a landform type of 6-25 degrees (after reclamation, the main characteristic is called as sloping field).

Red loam, also known as red loam, brick red loam, refers to a soil rich in iron oxide, aluminum oxide, and is generally considered to be formed in hot, humid tropical areas. Almost all laterites appear to be rust-red due to the high iron oxide content. The laterite soil has obvious structure and good ventilation and drainage. The soil is acidic, is not suitable for planting crops, is rich in viscosity and plasticity and poor in productivity, and can be matched with proper fertilizer cultivation management to improve the yield.

The present invention will be described in detail with reference to the following examples and the accompanying drawings.

Example 1 Material and method information relating to the invention

1. Summarizing the test site

The field test is carried out in the village of small hundred households in Qing county, qing-Liang county, jing, yunnan province at 8 months of 2023-2023 at 12 months. The soil type in the area is red soil, the pH of the test land is 4.85, the average elevation is 1870m, the annual average air temperature is 14-14.7 ℃, and the annual rainfall is about 1000 mm.

2. Test material

The tested variety is Lishu No. 6, and the winter potato variety has the advantages of high yield, high benefit and high quality.

The basic physicochemical properties of the test soil, red soil, and the plough layer (0-20 cm) soil are shown in Table 1.

The tested fertilizer varieties comprise urea, superphosphate and potassium sulfate.

TABLE 1 basic physicochemical Properties of soil tested

3. Test design

This example was performed using a field test method from 2023, 8, 1, to 2023, 12, 10, using a randomized block design, with each treatment repeated 3 times (n=3), for a total of 21 cells. The area of each cell is 55m ², and 16 rows of potatoes (320 plants, 27cm plant spacing and 62cm row spacing) are planted together. The test field was kept for 2 meters of protection.

The test set 7 treatments, respectively:

CK (no fertilizer + pesticide),

T1 (local conventional fertilization: 15-15-15+ pesticide), 1500 kg/ha, disposable basal application;

T2 (optimized fertilization 1:15-13.5-16.5+pesticide) 1200 kg/ha,2/3 as base fertilizer and 1/3 as additional fertilizer;

T3 (optimized fertilization 2:15-12-16.5+ pesticide), 1200 kg/ha,2/3 as base fertilizer, and 1/3 as additional fertilizer;

T4 (local conventional fertilization+phosphite), 1500 kg/ha, disposable basal application;

t5 (optimized fertilization of 1+ phosphite), 1200 kg/ha, 2/3 as base fertilizer and 1/3 as additional fertilizer;

T6 (optimized fertilization of 2+ phosphite), 1200 kg/ha, 2/3 as base fertilizer and 1/3 as top dressing.

T4, T5 and T6 replace chemical pesticides completely with phosphites.

Wherein 15-15, 15-13.5-16.5, 15-12-16.5 of T1, T2 and T3 represent the mass ratio of urea, superphosphate and potassium sulfate.

The potato enters the tuber expansion period for topdressing, the topdressing formula is consistent with the base fertilizer, and the topdressing is carried out once in the whole process.

The pesticide and phosphite are applied in such a way that after the potato enters the tuber forming growth period (4 weeks after sowing), the late blight prevention and control work is started. The pesticide conventionally used in the field is silver-method (Bayer company), and the main component is fluoxastrobin. Phosphite was used under the brand name of carboplox at an applied concentration of 2.5mM (PO ₃ ^3-). The pesticide and the phosphite are treated by adopting a leaf spraying mode, and the autumn potato diseases are relatively serious, so that the test agent is relatively frequently controlled, and is sprayed once every 7 days, and each time the pesticide is sprayed to a leaf full wet state (run off). The entire trial was applied 13 times in total.

4. Sample preparation

Plant samples of potato in vegetative growth phase, i.e., tuber forming phase, tuber expanding phase, starch forming phase and harvesting phase, were collected. According to the random principle, 3 cells were treated each, ten plants (excluding plants for disease observation) were randomly collected per cell, and a total of 210 potatoes were collected per growth period. And (3) naturally air-drying after collection, and grinding the obtained product by using a sieve with 0.5mm to determine the nitrogen, phosphorus and potassium nutrient content of the plant.

5. Measurement index

1) Plant sample assay

The plant total nitrogen is determined by Nahnsonian colorimetric method, the total phosphorus is determined by vanadium molybdenum Huang Bise method, and the total potassium is determined by flame photometer method.

2) Yield determination

During harvesting, four ridges which are not subjected to destructive sampling are randomly selected for theoretical yield measurement in each cell.

3) Determination of plant diseases

36 Potatoes are selected for each community to carry out disease investigation. Investigation was performed every two weeks until harvest. According to the disease stage number, calculating disease index and control effect by using McKinney disease index formula, and performing significance test on the control effect and phosphite control effect. The disease grading criteria are shown in Table 2

The disease index calculation formula:

Disease index = Σ (number of disease plants at each stage x corresponding number of stages)/total number of plants investigated x 5 x 100

Control effect (%) = Σ (treatment area control disease index-treatment area disease index)/treatment area control disease index×100%.

TABLE 2 Standard Table for grading the disease conditions of late blight of potato

Grade disease characterization

The whole plant 0 has no visible disease characteristics, and the color is normal and has no fading;

1, less than 1/4 of the whole plant leaves and stems show visible diseases, and a small amount of tissues fade;

2, the disease characteristics of 1/4-1/2 leaves and stems of the whole plant appear, and a proper amount of tissue fades;

3, 1/2-3/4 of the whole plant leaves and stems fade a large amount, and the leaves curl;

More than 3/4 of the stems of the whole plant become black, and all the leaves on the stems die;

5 dead whole plant

6. Data statistics and analysis

Data conditioning was performed using Excel, with SPSS13.0 alignment and normalization tests followed by one-way anova, duncan's and LSD test to test for significant differences (P < 0.05).

Example 2 results and data analysis

1. Soil nutrient content for each growth nutrient period of potatoes

Tuber forming period (figure 1A) T4 total phosphorus content is 2.91g/kg, T4 total phosphorus content is obviously higher than that of conventional fertilization and CK, CK treatment and conventional fertilization are respectively improved by 263.75% and 304.16%, tuber expanding period (figure 1B) is free from obvious difference among all treatments of soil total phosphorus, starch accumulating period (figure 1C) is obviously higher than that of CK, and T3 and T6 are respectively improved by 402.32% and 355.81% compared with CK.

The tuber forming period (figure 2A) has no significant difference between the soil total potassium and the T2 and the T5, the rest treatments have no significant difference, the tuber expanding period (figure 2B) has no significant difference between all treatments of the soil total potassium, and the starch accumulating period (figure 2C) has no significant difference between all treatments. The optimized fertilization formula improves the content of potassium.

2. Soil organic matter content of potato in each growth nutrition period

In the tuber forming period (figure 3A), the organic matter content of T6 is 29.17g/kg, and significant differences exist between the treatment (T4, T5 and T6) of the CK and the Shi Ya phosphate control treatment of the optimized formula, wherein the soil organic matters of T4, T5 and T6 are obviously higher than those of the CK treatment, and compared with the CK treatment, the CK is respectively improved by 29.62%,27.06% and 33.13%. There were no significant differences in all treatments during the tuber expansion period (fig. 3B) and in all treatments during the starch accumulation period (fig. 3C).

3. Soil available nutrient content of potato in each growth nutrition period

The alkaline hydrolysis nitrogen content of the soil between the T6 and CK treatments has a significant difference in tuber forming period (figure 4A), the CK in T6 is improved by 53.98% compared with the CK, the tuber expanding period (figure 4B) has no significant difference in all treatments, and the starch accumulating period (figure 4C) has no significant difference in all treatments.

The soil quick-acting phosphorus under the treatment of the tuber forming period (figure 5A) is obviously higher than that under the treatment of the conventional fertilization and the treatment of the T2 and the T4, however, the soil quick-acting phosphorus content is not obviously different between the conventional fertilization and the optimized fertilization, the soil quick-acting phosphorus under the treatment of the conventional fertilization and the treatment of the T4 and the T5 in the tuber expanding period (figure 5B) is obviously higher than that under the treatment of the other fertilization, and the soil quick-acting phosphorus under the treatment of the conventional fertilization, the treatment of the T1, the treatment of the T2, the treatment of the T5 and the treatment of the T6 is obviously higher than that under the treatment of the CK and the treatment of the T3 in the starch accumulating period.

Soil quick-acting potassium content at each growth stage (FIG. 6) there was a significant difference between the soil quick-acting potassium under T2 treatment and CK, conventional fertilization and T4 treatment during tuber formation, and no significant difference between the remaining treatments. The tuber expanding period has no significant difference in all treatments, the starch accumulating period has significant difference between CK and T4, T5 and T6, the CK is respectively increased by 60.82%,39.96% and 73.02% compared with the CK, the T4 and T6 are respectively increased by 44.93% and 26.10% compared with the conventional fertilization.

4. Content of potato plants in full

There was no significant difference between all treatments of plant total nitrogen (fig. 7A), however the optimized formulation had a total nitrogen content reduced by 45kg/ha compared to the local convention. All treatments of plant total phosphorus (fig. 7B) were not significantly different, while total phosphorus content was reduced in both optimized formulations, and it was seen that potatoes in this area had the potential for phosphate reduction. In addition, the phosphite is sprayed without significantly affecting the total phosphorus content of the plants. Of the total potassium content of the plants (fig. 7C), there was no significant difference between the three treatments (T4, T5, T6) with phosphite applied as late blight control, whereas the total potassium content of the T6 treatment was significantly lower than that of the T2 and CK treatments.

5. Impact on late blight of potato

As shown in Table 3, compared with the control of the fertilization and the pesticide, the optimized fertilization and the phosphite instead of the pesticide have the control effect on the potato late blight. During tuber formation, there was no significant difference between the disease index of the conventional fertilization of pesticide treatment T1, T3 and phosphite treatment T5, all significantly higher than the other treatments. There was no significant difference between the control effect of phosphite treated T4 and T6 on late blight and pesticide treated T2. In the tuber expanding period, the disease index is obviously increased in all other treatments except the T2 and T3 treatments compared with the tuber forming period. In terms of prevention and treatment effects, there is no obvious difference between the phosphite treated T4 and T6 and the pesticide treated T3, but the T2 prevention and treatment effects of adding and subtracting 15% of phosphorus outside the pesticide are optimal, and the T5 treatment effect is least obvious. The starch accumulation period is significantly higher than the tuber swelling period, and the disease index between treatments is significantly increased. In this stage, the treatment effect of T6 and T3 is optimal, which is significantly higher than that of other treatments, and the treatment effect of T5 is least obvious.

TABLE 3 prevention and treatment effects of potato late blight with phosphite instead of pesticide under different fertilization formulas

Note that T1 (local conventional fertilizer: 15-15-15+ pesticide), T2 optimized fertilizer 1 (15-13.5-16.5+ pesticide), T3 optimized fertilizer 2 (15-12-16.5+ pesticide), T4 (local conventional fertilizer+phosphite), T5 (optimized fertilizer 1+phosphite), T6 (optimized fertilizer 2+phosphite). Different capital letters A, B, C represent the same growth period, with significant differences between treatments (P < 0.05). Different lower case letters a, b, c represent the same treatment, the difference between different birth periods is significant (P < 0.05).

The results show that the accumulation of available nutrients in the soil is reduced by reducing the fertilizer consumption in the whole nutritional growth period of the potatoes, and the optimized fertilization formula improves the total nutrients in the soil and the physicochemical properties of the soil. And Shi Ya phosphate is sprayed to replace pesticide in the whole nutrition growth period of the potato, so that the potato seedling blight prevention and control method has good prevention and control effect on potato late blight. The optimized fertilization formula (T6) with 30 percent of phosphorus reduction has the best effect of preventing and controlling late blight and has no obvious difference with pesticide for preventing and controlling late blight, and the formula (T5) with the T6 treatment being obviously higher than 15 percent of phosphorus reduction, so that the Shi Ya phosphate has a certain effect on reducing the investment of phosphate fertilizer.

In conclusion, compared with conventional fertilization, the optimized formula fertilization treatment disclosed by the invention does not influence the content of soil nutrients and the accumulation of plant nutrients on the basis of fertilizer decrement, so that the experimental land has the potential of fertilizer decrement, and phosphite is used for replacing pesticides, so that the experimental land has a good prevention and treatment effect on potato late blight.

Claims

1. A method for planting potatoes on red soil sloping farmland, characterized in that the method comprises applying fertilizer for planting potatoes on red soil sloping farmland during the planting process; the fertilizer comprises urea, superphosphate and potassium sulfate, and the mass ratio thereof is 15:12-13.5:16.5; and during the planting period, phosphite is used to completely or partially replace pesticides to prevent and control potato late blight.

2. The method for planting potatoes on red soil sloping farmland as claimed in claim 1, characterized in that the mass ratio of urea, superphosphate and potassium sulfate is 15:13.5:16.5.

3. The method for planting potatoes on red soil sloping farmland as claimed in claim 1, characterized in that the mass ratio of urea, superphosphate and potassium sulfate is 15:12:16.5.

4. The method according to claim 1, wherein the method comprises applying 1200-1500 kg of fertilizer per hectare.

5. The method according to claim 4, characterized in that in the method, two thirds of the fertilizer is applied as basal fertilizer and one third of the fertilizer is applied as top dressing.

6. The method as claimed in claim 5, characterized in that the topdressing is carried out when the potatoes enter the tuber expansion stage.

7. The method according to claim 1, characterized in that the phosphite is applied by foliar spraying to control potato late blight.

8. The method of claim 7, wherein the phosphite is used at a concentration of 2.5 mM.