Method for building isolation belt to obstruct diaphorina citri

Abstract

The invention discloses a method for building an isolation belt to obstruct diaphorina citri, which comprises the following steps: planning an area for planting king grass around a citrus orchard to form an isolation belt, then planning the citrus orchard for planting citrus, selecting fresh, thick and strong stems of Hongyan No.4 king grass without diseases as seed stems, and planting the seeds in the isolation belt; cutting the seed stem into a section according to 2-3 sections to serve as seedlings for planting, performing water, fertilizer and disease and insect pest management, clipping the king grass for 4-6 times within one year to manage and protect an isolation belt formed by the king grass, and performing scientific water and fertilizer management after each time of clipping. The method solves the problems that the diaphorina citri migrates into a citrus orchard, directly harms citrus plants and spreads citrus huanglongbing in the citrus orchard, so that pesticide and labor cost investment is large, the service life of citrus trees is shortened, and ecological imbalance is caused.

Description

Technical Field

[0001] The invention relates to the technical field of pest management, and in particular to a method for establishing an isolation belt to block citrus psyllids. Background Art

[0002] Citrus psyllid (Diaphorina citri Kuwayama) belongs to the Hemiptera order, the Psyllidae family, and is one of the main pests on citrus. Its nymph stage is divided into 5 instars, and the adult body is about 3mm long. The body is emerald green when it first emerges, and then turns blue-gray with brown spots. The wings are white at the beginning of emergence, and the compound eyes are red. Then the forewings gradually turn translucent with black-brown spots, and the hind wings are transparent with obvious claws. When the adult is resting or feeding, the head is bent down, and the abdomen is tilted up at a 45° angle to the leaves. It is phototactic and likes to live on the periphery of the canopy and in sparse branches and leaves. Therefore, psyllids often stop and cause damage on the periphery of the canopy and the top of the tree. At the same time, it tends to be yellow, red, and tender leaves. Psyllids have strong jumping ability, and once they touch the branches, it is difficult to track their direction. The ability to migrate is weak, and long-distance damage is mainly accompanied by wind. The farthest it can fly is 100 meters, and the height can reach 7 meters. In dry and hot areas, the life span of adults is long, generations overlap seriously, and insect sources can be seen all year round.

[0003] Citrus psyllids can not only harm the tender shoots of plants through piercing and sucking by adults and nymphs, causing the tender parts of the plants to wither, deform, and twist, but the adults and nymphs can also attach to the plants through the secretion of honeydew, inducing sooty mold disease in the plants and affecting photosynthesis. More importantly, citrus psyllids are also the vector insects of Citrus Huanglongbing (HLB), a devastating disease in the citrus industry. Citrus Huanglongbing can infect a variety of Rutaceae plants such as Citrus, Trifoliate Orange, Fortunella, and Murraya Fragrant. Infected trees show various symptoms, including leaf chlorosis, twig dieback, fruit drop, deformity, small fruit, etc., resulting in reduced fruit quality, shortened economic life of the plants, and ultimately leading to the death of the fruit trees. In citrus orchards, the disease is mainly caused by citrus psyllids feeding on plants with Huanglongbing and laying eggs to produce a large number of adult insects with the disease. After the adults migrate in the orchard and feed on harmful healthy plants, they spread, transfer and spread the Huanglongbing pathogen (Candidatus Liberobacter asiaticus) in the orchard, which poses a devastating threat to the sustainable development of the citrus industry. However, no effective agent for treating HLB has been developed yet, and once the disease occurs, it can only be eliminated. Therefore, the prevention and control of citrus psyllids is still a key measure to control the spread of HLB. In field production, the prevention and control of citrus psyllids mainly adopts chemical control methods. The long-term use of chemical pesticides not only increases management costs, but also damages the environment, causes ecological imbalance, and causes excessive pesticide residues, affecting the health of fruit trees and humans. What is more serious is that the long-term use of chemical control makes the resistance of citrus psyllids to some pesticides more and more obvious. With the development of the industry, some orchards use nets to block citrus psyllids, but due to the high construction and maintenance costs, and the influence of environmental factors such as terrain, it has not been widely promoted and applied; some fruit farmers hang color plates and traps in the orchard to kill psyllids, but hanging color plates and devices not only kill psyllids but also kill many color-attracting natural enemies, which seriously affects the ecological balance between species in the orange orchard. At the same time, it will also lure insect sources outside the orchard into the orchard, resulting in the disadvantages of artificially introducing pests and indirectly causing Huanglongbing to enter the orchard. Therefore, low-cost, simple, and practical physical prevention and control is becoming more and more important. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] Therefore, the present invention solves the problem that citrus psyllids migrate into citrus orchards, directly harm citrus plants and spread citrus Huanglongbing disease in citrus orchards, resulting in large investment in pesticides and labor costs, shortening the life of citrus trees and causing ecological imbalance.

[0006] To solve the above technical problems, according to one aspect of the present invention, the present invention provides the following technical solutions:

[0007] A method for establishing an isolation zone to block citrus psyllids, the steps are as follows:

[0008] S1. Plan an area for planting king grass around the citrus orchard to form an isolation zone, and then plan the citrus orchard for planting citrus;

[0009] S2, select fresh, strong, disease-free Reyan No. 4 king grass stems as seed stems, then cut the seed stems into sections of 2-3 nodes for planting as seedlings, and manage water, fertilizer, diseases and pests;

[0010] S3. Mow the royal grass 4-6 times a year to maintain the isolation zone formed by the royal grass, and perform water and fertilizer management after each mowing.

[0011] As a preferred embodiment of the method for establishing an isolation zone to isolate citrus psyllids according to the present invention, in step S1, an area for planting king grass is planned around a citrus orchard, and then the specific steps of planning the citrus orchard for planting citrus are as follows:

[0012] First, the 2m wide plot around the citrus orchard was plowed 40cm deep. Secondly, 7 planting trenches with a width of 30cm and a depth of 20cm were dug. Then, farmyard manure was spread at a rate of 500-1000kg per mu or compound fertilizer was spread at 50kg / mu. Finally, 5cm of soil was covered and waiting for planting.

[0013] When the royal grass grows to about 1m in height, the entire citrus field is sterilized and insecticidal, then deep plowing and ridge making are carried out. During deep plowing, decomposed organic fertilizer and arbuscular mycorrhizal fungi are added, mixed evenly and then returned to the pond for ridge making. The ridge height is 20-40cm, the bottom width is 2m, and the ridge spacing is 2m.

[0014] As a preferred embodiment of the method for establishing an isolation zone to block citrus psyllids described in the present invention, the deep plowing depth is 80 cm.

[0015] As a preferred embodiment of the method for establishing an isolation zone to block citrus psyllids described in the present invention, in step S2, the specific steps for planting the seedlings are as follows: soak the seedlings in rooting powder for 30 minutes before planting, then insert the royal grass obliquely in the planned planting ditch at a spacing of 0.3m per section, cover with soil, and water enough to establish roots.

[0016] As a preferred embodiment of the method for establishing an isolation zone to block citrus psyllids described in the present invention, in step S2, the steps of water and fertilizer are as follows: water once 2-3 days after planting to ensure that the planting furrows are moisturized at all times, start intertillage and weeding when the seedlings are 50 cm tall, and water frequently during the seedling stage to moisturize the roots. When the plants are 50 cm tall, combine intertillage and weeding with topdressing of farmyard manure to promote tillering and elongation of the seedlings.

[0017] As a preferred embodiment of the method for establishing an isolation zone to isolate citrus psyllids described in the present invention, in step S2, the steps of pest management are as follows: reduce the humidity of the royal grass environment, drain the accumulated water in time after rain, spray fenpropimorph and pyraclostrobin after the disease occurs, and use sugar wine or poisonous rice bran to lure and kill the larvae.

[0018] As a preferred embodiment of the method for establishing an isolation zone to isolate citrus psyllids described in the present invention, the poisonous rice bran includes fried rice bran, dichlorvos and brown sugar, wherein the ratio of fried rice bran: dichlorvos: brown sugar = 1000g: 500g: 10g.

[0019] As a preferred embodiment of the method for establishing an isolation belt to block citrus psyllids described in the present invention, in step S3, the step of mowing the king grass is as follows: mowing the king grass when its height is above 2m, leaving a stubble height of 15cm each time when mowing, not mowing on rainy days, and breaking it up after mowing and spreading it between plants and rows in the citrus orchard to suppress the grass, retain water and keep warm;

[0020] When mowing, do it from the inside of the garden to the outside. In the early stage, mow the inner 3 rows first. When the inner three rows grow to 1m high, mow the 4th row. When the 4th row grows and the previously mowed 3 rows grow to more than 2m, mow the outer 3 rows. Subsequent mowing is done in this order. When the 4th row of the shed expands to 15cm wide, no more mowing is done. The 4th row of royal grass is interspersed and arranged into a fence shape. Only the inner 3 rows and the outer 3 rows are mowed. The mowing height is more than 2m.

[0021] As a preferred embodiment of the method for establishing an isolation zone to block citrus psyllids described in the present invention, in step S3, the steps of water and fertilizer management for the mowed royal grass are as follows: replenish water in time after each mowing to ensure soil moistening, and replenish sufficient nutrients in time, use 15:15:15+TE water-soluble fertilizer of Yuntianhua for replenishment, and spread it at a ratio of 20kg per mu. The last mowing before winter, after mowing, the nutrition supplement is a mixture of urea + organic fertilizer or decomposed farmyard manure. Urea is first applied at a ratio of 50kg; then organic fertilizer is applied at a ratio of 1000kg per mu.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention prevents citrus psyllids from entering the citrus orchard by planting the royal grass "Reyan No. 4" around the citrus orchard in advance, changing the current method of trapping and killing citrus psyllids and indirectly introducing citrus psyllids into the orchard, causing citrus psyllids to harm citrus, and bringing pathogens into the orchard to spread and spread, and preventing citrus psyllids from entering the citrus orchard to harm citrus, and preventing citrus psyllids from bringing in, spreading and spreading citrus Huanglongbing, extending the growth period of citrus, and solving the problem of cutting down and removing Huanglongbing when citrus fruits are just bearing fruit or just entering the peak production period. It also changes a series of problems such as fruit quality pollution, environmental pollution, resistance of psyllids, and large investment of manpower and material resources caused by spraying pesticides in large quantities in the orchard to prevent and control citrus psyllids many times to prevent and control citrus psyllids, and achieves the effect of reducing costs and obtaining high-quality returns, and is one step closer to green production.

[0024] 2. Cutting and crushing the royal grass and spreading it in the garden can suppress the weeds, achieving the goal of using grass to suppress weeds while retaining water and heat to improve the microclimate in the garden. After the royal grass rots, it can also add organic matter to the soil in the garden, improve soil fertility, improve the soil microbial flora in the garden and increase its diversity. It realizes a good ecosystem of the orange garden of "taking from the soil and returning to the soil"; it builds a healthy ecological environment above the trees and underground, and fertilizes the soil in the orange garden. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in combination with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0026] Figure 1 The present invention is a flow chart of a method for establishing an isolation zone to block citrus psyllids. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] Secondly, the present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] The present invention provides a method for establishing an isolation belt to block citrus psyllids, comprising the following steps:

[0031] (I) Planning: After selecting the plot, the area around the orchard should be planned in advance. First, the area around the citrus orchard should be planned and the king grass should be planted. Then the middle plot should be planned and citrus should be planted.

[0032] 1. Planning of isolation belt

[0033] First, deep plow the 2m wide plot around the orchard to 40cm; secondly, dig 7 planting trenches with a width of 30cm and a depth of 20cm; then, spread farmyard manure at a rate of 500-1000kg per mu or compound fertilizer at a rate of 50kg / mu; finally, cover with 5cm of soil and wait for planting.

[0034] 2. Planning of citrus orchard

[0035] When the royal grass grows to a height of about 1m, the entire citrus field is sterilized and insecticidal, and then deep plowing and ridge making are carried out. The deep plowing depth can be 80cm. When deep plowing, add decomposed organic fertilizer and arbuscular mycorrhizal fungi (AMF), mix them evenly and then return them to the pond for ridge making. The ridge height is 20-40cm, the ridge bottom width is 2m, and the ridge spacing is 2m.

[0036] To sum up, planning the isolation zone in advance is to build the isolation zone first and serve as a barrier; sterilization and pest control will be carried out in the citrus planting area after the isolation zone is built in order to artificially kill the existing pests and diseases in the garden and establish a clean and safe growth environment for the citrus seedlings to enter.

[0037] (2) Planting king grass

[0038] 1. Seed stem selection

[0039] Select fresh, thick, disease-free stems of Reyan No. 4 King Grass as seed stems, and then cut the seed stems into sections of 2-3 nodes as seedlings.

[0040] 2. Planting

[0041] Soak the plant in rooting powder (according to the concentration in the instructions) for 30 minutes before planting. Then, insert the king grass obliquely into the planned planting ditch at a spacing of 0.3m per section, cover with soil, and water enough to establish roots.

[0042] 3. Post-planting water and fertilizer management

[0043] Water once every 2-3 days after planting, and keep the planting furrow moist at all times; start intertillage and weeding when the seedlings are about 50cm tall, and be careful not to damage the roots and stems. Water frequently during the seedling stage to moisten the roots. When the plants are about 50cm tall, combine intertillage and weeding with topdressing of farmyard manure to promote tillering and elongation of the seedlings.

[0044] 4. Post-planting pest and disease management

[0045] Reyan No. 4 Wangcao has strong resistance to diseases and pests, and rarely suffers from diseases and pests. In some places, anthrax may occur in cold and rainy seasons; underground pests may harm some areas. The symptoms of the disease are: brown circular patches with small black or pink colloid particles on them. When dry, the lesions die and become sunken. Prevention and control methods: reduce the humidity of the environment, drain the accumulated water in time after rain; after the disease occurs, spray agents such as fenpropimorph and pyraclostrobin. For underground pests such as cutworms and grubs, black light can be used to lure and kill adults, and sugar wine or poisonous rice bran (fried rice bran: dichlorvos: a small amount of brown sugar = 1000g: 500g; 10g) can be used to lure and kill larvae. If other diseases and pests occur, normal pesticide control can be used.

[0046] In summary, choosing fresh, disease-free stems is conducive to the growth of healthy and strong stem buds; selecting 2-3 nodes as a section can better utilize the stem seeds; soaking the stems in rooting powder before planting is conducive to replenishing water and rooting and growing stem buds faster; oblique planting is also for faster growth of stem buds.

[0047] (III) Management and maintenance of isolation zones

[0048] 1. Mowing

[0049] Reyan No. 4 Wangcao can be mowed 4-6 times a year, and mowed when the grass is above 2m, leaving a stubble height of 15cm each time. Mowing is not allowed on rainy days. After mowing, it is broken and spread between the plants and rows in the citrus orchard to suppress weeds, retain water and keep warm; thereby reducing a large amount of weeding work in the orchard, playing the role of "controlling weeds with grass"; after it is decomposed, it can also provide a large amount of organic fertilizer for the orange orchard, so that the orange orchard only needs to apply organic fertilizer in the first year, and no organic fertilizer needs to be added later.

[0050] Mowing should be done from the inside to the outside. In the early stage, mow the inner three rows first, and when the inner three rows grow to 1m high, mow the fourth row. When the fourth row grows and the previously mowed three rows grow to more than 2m, mow the outer three rows. Subsequent mowing is carried out in this order. When the fourth row of the shed expands to about 15cm wide, no more mowing is carried out. The fourth row of king grass is interlaced and arranged into a fence shape, and only the inner three rows and the outer three rows are mowed. The mowing height is above 2.

[0051] 2. Water and fertilizer management after mowing

[0052] After each mowing, water must be added in time to ensure that the soil is moist and sufficient nutrients are added in time. The main supplement is to use Yuntianhua's water-soluble fertilizer of 15:15:15+TE, at a rate of 20kg per mu. The last mowing before winter, after mowing, the nutrient supplement is a mixture of urea + organic fertilizer or decomposed farmyard manure. This time, urea is first applied at a rate of 50kg; then organic fertilizer is applied at a rate of 1000kg per mu, and farmyard manure can be applied more, but it must be decomposed before application.

[0053] (IV) Occurrence of pests and diseases in orange orchards

[0054] The present invention is mainly used to block citrus psyllids. After many years of continuous investigation, no citrus psyllids have been found in the orchard, and the number of times the pesticides are used in the orchard is significantly lower than that in the adjacent citrus orchard. At the same time, it is found that the density of citrus psyllids in the adjacent citrus orchards shows an increasing trend year by year during the same phenological period of citrus, and the citrus Huanglongbing disease has a tendency to spread in the citrus orchard. It is also found that the density of citrus red spider mites, thrips, and lepidoptera pests in the orchard within the isolation zone is also significantly lower than that in the adjacent citrus orchard.

[0055] After mowing, the royal grass was broken into pieces and spread between the plants and rows in the orchard. In the plots where it was spread, weeding was only done once in the first year of planting. In the second year, as the citrus trees grew and were covered with royal grass debris, weeding was almost not done. Only a small amount of weeds occasionally grew in the orange orchard, which had no impact on the trees.

[0056] In summary, compared with the neighboring citrus orchards, the orchard of the present invention prevents the direct and indirect harm to citrus trees caused by citrus psyllids entering the citrus orchard; it also reduces the number of times of using medicines to prevent and control citrus psyllids, reduces the types of medicines used, and the amount of medicines used; reduces the amount of organic fertilizers used in the citrus orchard, and establishes a good ecosystem in the citrus orchard; realizes the virtuous cycle of "using grass to control grass, using grass to nourish the land, and using grass to promote nutrition" in the orchard; and ultimately extends the growth period of citrus trees and produces high-quality, healthy fruits.

[0057] After using the scheme of the present invention, not only can external citrus psyllids be blocked, but also most of the pests and diseases that harm citrus can be blocked outside the orchard. More importantly, the dangerous disease - citrus Huanglongbing can be blocked outside the orange orchard.

[0058] After using the present invention, a good ecosystem of the orange orchard is artificially established, a healthy ecological environment on the trees and underground is formed, the soil of the orange orchard is fertilized, and the planting period of citrus is extended to the maximum extent.

[0059] The use of the present invention can change the "three R" problems caused by multiple spraying of chemical pesticides to control citrus psyllids, and also greatly shorten the labor input and chemical pesticide input, thus achieving a virtuous cycle of reducing input, improving quality and output value.

[0060] After using the present invention, the harm caused by weeds in the orchard can be reduced, the labor of weeding can be reduced, the content of organic matter in the orchard can be increased, the water retention and temperature control capabilities of the orchard soil can be improved, and the soil microbial population can be increased, providing a high-quality soil environment for the growth of citrus roots.

[0061] Although the present invention has been described above with reference to the embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed in the present invention may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for establishing an isolation zone to block citrus psyllids, characterized in that: Here are the steps: S1. Plan an area for planting king grass around the citrus orchard to form an isolation zone, and then plan the citrus orchard for planting citrus; S2, select fresh, strong, disease-free Reyan No. 4 king grass stems as seed stems, then cut the seed stems into sections of 2-3 nodes for planting as seedlings, and manage water, fertilizer, diseases and pests; S3. Mow the royal grass 4-6 times a year to maintain the isolation zone formed by the royal grass, and perform water and fertilizer management after each mowing.

2. A method for establishing an isolation zone to block citrus psyllids according to claim 1, characterized in that: In step S1, the specific steps of planning an area for planting royal grass around the citrus orchard and then planning the citrus orchard for planting citrus are as follows: First, the 2m wide plot around the citrus orchard was plowed 40cm deep. Secondly, 7 planting trenches with a width of 30cm and a depth of 20cm were dug. Then, farmyard manure was spread at a rate of 500-1000kg per mu or compound fertilizer was spread at 50kg / mu. Finally, 5cm of soil was covered and waiting for planting. When the royal grass grows to about 1m in height, the entire citrus field is sterilized and insecticidal, then deep plowing and ridge making are carried out. During deep plowing, decomposed organic fertilizer and arbuscular mycorrhizal fungi are added, mixed evenly and then returned to the pond for ridge making. The ridge height is 20-40cm, the bottom width is 2m, and the ridge spacing is 2m.

3. A method for establishing an isolation zone to block citrus psyllids according to claim 2, characterized in that: The deep plowing depth is 80cm.

4. The method for establishing an isolation zone to isolate citrus psyllids according to claim 1, characterized in that: In step S2, the specific steps for planting the seedlings are as follows: soak them in rooting powder for 30 minutes before planting, then insert the royal grass obliquely into the planned planting ditch at a spacing of 0.3m per section, cover them with soil, and water them enough for the roots to take root.

5. The method for establishing an isolation zone to isolate citrus psyllids according to claim 1, characterized in that: In step S2, the steps of water and fertilizer are as follows: water once every 2-3 days after planting to ensure that the planting furrows are moisturized at all times, start inter-row cultivation and weeding when the seedlings are 50 cm tall, and water frequently during the seedling stage to moisturize the roots. When the plants are 50 cm tall, combine inter-row cultivation and weeding with topdressing of farmyard manure to promote tillering and elongation of the seedlings.

6. The method of establishing an isolation zone to block citrus psyllids according to claim 1, characterized in that: In step S2, the steps of pest management are as follows: reduce the humidity of the royal grass environment and drain the accumulated water in time after rain; spray fenpropimorph or pyraclostrobin after the disease occurs; when insect pests occur, use sugar wine or poisonous rice bran to lure and kill the larvae.

7. A method for establishing an isolation zone to block citrus psyllids according to claim 6, characterized in that: The toxic rice bran includes fried rice bran, dichlorvos and brown sugar, among which, fried rice bran: dichlorvos: brown sugar = 1000g:500g:10g.

8. The method of establishing an isolation zone to isolate citrus psyllids according to claim 1, characterized in that: In step S3, the steps of mowing the king grass are as follows: mowing the king grass when its height is above 2m, leaving a stubble height of 15cm each time when mowing, not mowing on rainy days, breaking it up after mowing and spreading it between plants and rows in the citrus orchard to suppress the grass, retain water and keep warm; Mowing is done from the inside of the garden to the outside. In the early stage, the inner 3 rows are mowed first. When the inner three rows grow to 1m high, the 4th row is mowed. When the 4th row grows and the previously mowed 3 rows grow to more than 2m, the outer 3 rows are mowed. Subsequent mowing is done in this order. When the 4th row of the shed expands to 15cm wide, no more mowing is done. The 4th row of royal grass is interspersed and arranged into a fence shape. After that, only the inner 3 rows and the outer 3 rows are mowed, and the mowing height is more than 2m.

9. The method for establishing an isolation zone to isolate citrus psyllids according to claim 1, characterized in that: In step S3, the steps of water and fertilizer management for the mowed royal grass are as follows: replenish water in time after each mowing to ensure soil moistening, and replenish sufficient nutrients in time. When replenishing, use 15:15:15+TE Yuntianhua's water-soluble fertilizer, and spread it at a rate of 20kg per mu; the last mowing before winter, the nutritional supplement after mowing is a mixture of urea + organic fertilizer or decomposed farmyard manure. This time, urea is first applied at a rate of 50kg; then organic fertilizer is applied at a rate of 1000kg per mu.

Images