Method for improving eclosion rate of larvae or nymphs of macadamia nut juice-eating leaf insects

Abstract

The invention discloses a method for improving the eclosion rate of larvae or nymphs of macadamia nut juice-eating leaf insects, and belongs to the technical field of insect feeding. The invention discloses a method for improving eclosion rate of larvae or nymphs of macadamia nut juicy leaf insects, which comprises the following steps: covering the larvae or nymphs and newly-drawn tender shoots with a white nylon mesh bag with 200-300 meshes, and tightening the bag opening with a rope, so that the larvae or nymphs cannot escape. If the tender leaves are completely eaten or the tender shoot juice is completely sucked, larvae or nymphs need to be transferred to another newly-drawn tender shoot until the larvae pupate and eclosion, and adults are collected for research. By means of the method, the eclosion rate of larvae or nymphs can be increased to 80% or above.

Description

Technical Field

[0001] The present invention relates to the technical field of insect breeding, and more particularly to a method for improving the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects. Background Art

[0002] Macadamia nuts (Macadamia spp.), also known as macadamia nuts, Australian walnuts, Queensland nuts, etc., are evergreen tree fruit trees of the genus Macadamia (Macadamia F.Muell.) of the Proteaceae family. They are native to the subtropical rainforest areas along the southeastern coast of Queensland and northeastern New South Wales, Australia, and are known as the "Queen of Dried Fruits". Macadamia nuts are rich in nutritional value and high in oil content. They are superior edible nuts and important woody oils. In addition to being cultivated in Australia, they have been introduced and cultivated in more than 20 countries including my country, South Africa, Kenya, Guatemala, the United States, and Brazil. By the end of 2023, the global macadamia planting area is about 8.5585 million mu, of which 5.2336 million mu are in China, accounting for 61.15%. In my country, macadamia nuts are mainly planted in southwestern provinces, of which Yunnan Province has planted 4.0995 million mu, accounting for 78.33% of the country. Yunnan has become the world's largest macadamia planting base.

[0003] With the continuous expansion of planting areas and the extension of planting years, the number of insects that harm macadamia nuts has also continued to increase. It is reported that there are more than 330 species. Most of these insects are important pests. They greatly reduce the quality and yield of macadamia nuts and reduce the economic benefits of macadamia nuts. Among these pests, insects that feed on the sap and leaves of macadamia trees (i.e., sap-eating leaves) account for a large proportion. During field surveys and collections, larvae (or nymphs, all larvae mentioned below include nymphs) of sap-eating leaf insects are often collected. These larvae mostly belong to Lepidoptera, Hemiptera or Coleoptera (such as geometrid moths, wax cicadas, leaf beetles, etc.). Because the current larval identification system is missing or imperfect, the specific species cannot be identified based on the larval morphology, and it cannot correspond to the adult morphology. In order to accurately identify these insects, make adult specimens or establish experimental populations for subsequent biological and ecological studies, it is necessary to bring these larvae back indoors to raise them to adults and multiply them. In this process, the larvae are difficult to hatch into adults (i.e., difficult to raise smoothly). In the actual process, the hatching rate (survival rate from larvae to adults) is less than 40%, and the larvae often die midway. The cause of death is related to the breeding method.

[0004] At present, the commonly used larval rearing method is indoor rearing, including the following: ① Sealed rearing in bags. For example, put the larvae and the detached leaf shoots together in a self-sealing bag, and feed the leaf shoots continuously until the larvae emerge as adults. The advantage of this is that it is easy to observe, and the larvae's every move can be seen, and the larvae will not escape, and will not be threatened by natural enemies. The disadvantage is that the bag is not breathable, and after a few hours, the top of the bag will be filled with water vapor or water droplets. The relative humidity in the bag is 100%, which is too humid for insects, and the leaves will mold in one or two days. In actual application of this method, the larval emergence rate is very low. ② Rearing in small breeding cages. This method is to place the larvae on detached branches and leaves, and then put them together in a breeding cage and wait for the larvae to emerge. Because the breeding cage is breathable and does not retain water, the branches and leaves wilt in one or two days, and the larvae are no longer willing to feed. Therefore, fresh branches and leaves must be collected almost every day, and the larvae must be carefully transferred to the newly collected branches and leaves, which is time-consuming and laborious. The larvae are constantly disturbed and struggle to survive in hunger and fullness. The emergence rate is very low, and this method is not feasible for some insects. For example, many old larvae and adults of scale insects need to be fixed to cause harm. Frequent replacement makes it impossible for them to be fixed and unable to survive. ③ Raise in medium and large breeding cages. Place the larvae on the tender shoots of potted seedlings, and then put them into the breeding cage together with the potted seedlings for breeding. This method requires preparing potted seedlings first, which invisibly increases a lot of workload. And the potted seedlings will lose vitality and gradually die if they cannot see the sun for a long time. Or place the larvae on the macadamia tree in the field base, and then cover the whole nut tree with a medium and large breeding cage for outdoor breeding. The biggest problem with this method is that if small insects are placed on a large seedling for a long time, they will escape, which not only makes it inconvenient to observe their life history, but also makes it impossible to find the insects in the end; and in the process of covering the whole tree with a breeding cage, it is inevitable that predatory and parasitic natural enemies will be covered together, and these natural enemies will feed on the larvae, thereby reducing the emergence rate. Based on this, it is necessary to find a simple, easy and effective breeding method to improve the emergence rate of sap-feeding leaf larvae collected in the wild.

[0005] Therefore, providing a method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] In view of this, the present invention provides a method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects, comprising the following steps:

[0009] (1) Collecting larvae or nymphs in the wild:

[0010] Collect healthy live larvae or nymphs of macadamia nut juice-feeding leaf insects from the wild, put them into a ziplock bag of appropriate size along with an appropriate amount of tender shoots, and bring them back indoors;

[0011] (2) Look for new shoots:

[0012] Look for new shoots on the macadamia trees at the base or on the macadamia seedlings in the lab pot;

[0013] (3) Net bags cover larvae or nymphs and tender shoots:

[0014] Transfer the insect larvae or nymphs to the newly grown tender shoots found, then use a net bag to completely cover the larvae or nymphs and the newly grown tender shoots, tie the bag mouth with a rope, and tie it to the branches near the base of the tender shoots, so that the larvae or nymphs cannot escape;

[0015] (4) Transfer larvae or nymphs when necessary:

[0016] If the larvae or nymphs have eaten all the leaves on the tender shoots, they need to be promptly transferred to the next new tender shoot until they emerge as adults.

[0017] (5) Collecting adults:

[0018] The newly emerged adults were collected and brought to the laboratory for subsequent research.

[0019] Furthermore, the larvae or nymphs of the sap-feeding leaf insects in step (1) are larvae or nymphs of Lepidoptera, Hemiptera or Coleoptera insects that feed on macadamia nut juice or leaves.

[0020] Furthermore, the top of the newly emerged tender shoots in step (2) contains tender leaves that have not yet fully emerged and unfolded, and the newly emerged tender shoots are tender shoots in the middle and lower layers of the macadamia nut tree.

[0021] Furthermore, the mesh size of the mesh bag in step (3) is 200-300 mesh and it is a white nylon mesh bag.

[0022] It can be known from the above technical solutions that, compared with the prior art, the present invention discloses a method for improving the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects. This method avoids the drawbacks of being filled with water vapor or water droplets and being too humid during "sealed breeding in bags", makes up for the deficiency of wilting of in vitro branches and leaves during "breeding in small breeding cages", and prevents the escape of target insects during "breeding in medium and large breeding cages". At the same time, because the larvae are confined in the net bag, their development process can be observed in real time. The barrier of the net bag also effectively avoids the predation of predatory natural enemies on the larvae and effectively avoids the parasitism of parasitic natural enemies on the larvae, thereby ensuring that the larvae successfully emerge into adults. The tender shoots in the middle and lower layers are effectively protected from direct sunlight, preventing excessively high temperatures from affecting the growth and development of the larvae, and preventing high temperatures from killing the larvae, thereby improving the emergence rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0024] Figure 1 The accompanying drawings are embodiments of the present invention;

[0025] Figure 2 The attached figure shows the closed feeding state in the bag;

[0026] Figure 3 The attached figure shows the state of breeding in a small breeding cage;

[0027] Figure 4 The attached figure shows the breeding conditions in a medium to large breeding cage. DETAILED DESCRIPTION

[0028] 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.

[0029] The culture environment and culture conditions used in the present invention do not need to be particularly limited, as long as they can ensure the normal growth and development of the insect larvae or nymphs.

[0030] Example 1

[0031] A method for increasing the emergence rate of nymphs of macadamia nut juice-feeding leaf insect white moth wax cicada:

[0032] The third-instar nymphs of the white moth were taken and four methods (the present invention - rearing on potted macadamia seedlings ( Figure 1 ), sealed in bags ( Figure 2 ), raised in small cages ( Figure 3 ), raised in medium to large cages ( Figure 4 )) were used for breeding, 20 heads were raised for each method; the experiment was repeated 3 times; the emergence rate was calculated after the nymphs of the white moth wax cicada completely emerged into adults.

[0033] The method of the present invention comprises the following steps: using potted macadamia nut seedlings, selecting newly sprouted tender shoots whose tops contain tender leaves that have not been completely sprouted and unfolded, and are tender shoots at the middle and lower layers; transferring nymphs to the newly sprouted tender shoots that have been found, using a white nylon mesh bag (the mesh size is 300 meshes, and the length×width of the mesh bag is 26 cm×38 cm) to completely cover the nymphs and the newly sprouted tender shoots, tying the bag mouth with a rope, and restraining the bag on branches near the base of the tender shoots, so that the nymphs cannot escape.

[0034] Sealed breeding in bags: No. 11 self-sealing bags (length × width = 38 cm × 26 cm) were used.

[0035] Raise in a small breeding cage: The size of the breeding cage is 60cm×60cm×60cm.

[0036] Raise in medium to large breeding cages: The size of the breeding cage is 100cm×100cm×160cm.

[0037] The results of emergence rate are shown in Table 1.

[0038] Table 1 The emergence rate of the third instar nymphs of the white moth with different rearing methods

[0039]

[0040] Note: Different capital letters after numbers in different rows indicate extremely significant differences.

[0041] The results in Table 1 show that the emergence rate of the method of the present invention is significantly higher than that of the other three methods.

[0042] Example 2

[0043] A method for increasing the emergence rate of larvae of macadamia nut juice-feeding leaf insect Lymantria thunbergii:

[0044] The third instar larvae of the Oryctolagus thunbergii were taken and raised using four methods (the present invention - raising on potted macadamia nut seedlings, raising in a closed bag, raising in a small-sized raising cage, and raising in a medium-sized and large-sized raising cage), with 10 larvae raised using each method; the experiment was repeated 3 times; and the emergence rate was counted after the larvae of the Oryctolagus thunbergii completely emerged into adults.

[0045] The method of the present invention comprises the following steps: using potted macadamia nut seedlings, selecting newly sprouted tender shoots whose tops contain tender leaves that have not been completely sprouted and unfolded, and are tender shoots at the middle and lower layers; transferring nymphs to the newly sprouted tender shoots that have been found, using a white nylon mesh bag (with a mesh size of 200 meshes, and a mesh bag length×width=26 cm×38 cm) to completely cover the larvae and the newly sprouted tender shoots, tying the bag mouth with a rope, and restraining the bag on branches near the base of the tender shoots, so that the larvae cannot escape.

[0046] Sealed breeding in bags: No. 11 self-sealing bags (length × width = 38 cm × 26 cm) were used.

[0047] Raise in a small breeding cage: The size of the breeding cage is 60cm×60cm×60cm.

[0048] Raise in medium to large breeding cages: The size of the breeding cage is 100cm×100cm×160cm.

[0049] The results of emergence rate are shown in Table 2.

[0050] Table 2 The emergence rate of larvae of the gypsy moth under different rearing methods

[0051]

[0052]

[0053] Note: Different capital letters after numbers in different rows indicate extremely significant differences.

[0054] The results in Table 2 show that the emergence rate of the method of the present invention is significantly higher than that of the other three methods.

[0055] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects, characterized in that: The following steps are involved: (1) Collecting larvae or nymphs in the wild: Collect healthy live larvae or nymphs of macadamia nut juice-feeding leaf insects from the wild, put them into a ziplock bag of appropriate size along with an appropriate amount of tender shoots, and bring them back indoors; (2) Look for new shoots: Look for new shoots on the macadamia trees at the base or on the macadamia seedlings in the lab pot; (3) Net bags cover larvae or nymphs and tender shoots: Transfer the insect larvae or nymphs to the newly grown tender shoots found, then use a net bag to completely cover the larvae or nymphs and the newly grown tender shoots, tie the bag mouth with a rope, and tie it to the branches near the base of the tender shoots, so that the larvae or nymphs cannot escape; (4) Transfer larvae or nymphs when necessary: If the larvae or nymphs have eaten all the leaves on the tender shoots, they need to be promptly transferred to the next new tender shoot until they emerge as adults. (5) Collecting adults: The newly emerged adults were collected and brought to the laboratory for subsequent research.

2. A method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects according to claim 1, characterized in that: The larvae or nymphs of the sap-feeding leaf insects in step (1) are larvae or nymphs of Lepidoptera, Hemiptera or Coleoptera insects that feed on the sap or leaves of macadamia nuts.

3. The method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects according to claim 1, characterized in that: The top of the newly grown shoots in step (2) contains young leaves that have not yet fully grown out and unfolded, and the newly grown shoots are the middle and lower shoots of the macadamia nut tree.

4. The method for increasing the emergence rate of larvae or nymphs of macadamia nut juice-feeding leaf insects according to claim 1, characterized in that: The mesh size of the mesh bag in step (3) is 200-300 meshes and it is a white nylon mesh bag.

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