WO2019053748A1

WO2019053748A1 - Biopesticidal composition

Info

Publication number: WO2019053748A1
Application number: PCT/IN2018/050604
Authority: WO
Inventors: Rahul Raju KANUMURU; Muthuvaduganathan NAGASUNDRAM; Perumal Shanthakumar SHANMUGAM
Original assignee: Fertis India Pvt. Ltd.
Priority date: 2017-09-18
Filing date: 2018-09-18
Publication date: 2019-03-21

Abstract

The present invention relates to a bio-pesticidal composition comprising a mixture of two tree oils and an insect cuticle desiccant for controlling or preventing insect infestation in agriculture, granaries and plantations. The present bio-pesticidal composition avoids the use of toxic organic solvents in its preparation; therefore, residues of the said composition in agricultural run-off do not have any adverse effect on the environment. The present composition is a stable solution with higher solubility efficiency in distilled water.

Description

BIOPESTICIDAL COMPOSITION

TECHNICAL FIELD OF THE INVENTION:

The present invention relates to a bio-pesticidal composition comprising a mixture of two tree seed oils and an insect cuticle degrading component.

Further, the present invention relates to a bio-pesticidal composition for controlling or preventing insect infestation in agriculture, granaries and plantations.

BACKGROUND AND PRIOR ART OF THE INVENTION:

Bio-pesticides are mass-produced, biologically based agents used for the control of plant pests. They can be living organisms such as nematodes or micro-organisms or naturally occurring compounds, such as phytochemicals present in plant extracts or insect pheromones. Microbial bio-controls might act as competitors or inducers of plant host resistance. Some act by inhibiting the growth, feeding, development or reproduction of a pest or pathogen. Still other bio-controls may be used to form a barrier on the host, so as to act as a feeding or infection inhibitor.

Plant extracts were likely the earliest agricultural bio-controls, as history records that nicotine was used to control plum beetles as early as the 17^th century. Experiments with mineral oils as plant protectants were also reported in the 19^th century. During the rapid institutional expansion of agricultural research during the early 20^th century, an ever-growing number of studies and proposal for bio-control agents were developed.

Bio-pesticides are being used on increasing scales and there is considerable interest in their potential as alternatives to conventional pesticides.

Pesticide products have been formulated from botanical and other natural sources. A widely used instance is that of the pyrethrin group of pesticides derived from the pyrethrum daisy, Chrysanthemum cinerariaefolium. Other examples include: rotenone, obtained from the roots of Derris lonchocatpus; ryania, stems of Ryania speciosa; and azadirachtin derived from the leaves, bark and seeds of Azadirachta indica. However, these synthetic varieties are highly commercialized and chemically refined, therefore contributing to eutrophi cation and bio-accumulation. These derivatives of these chemical compounds eventually reach the food chain causing harmful effects to humans, livestock and plants.

Therefore, there is an increasing trend to rely on bio-pesticidal and bio-pesticidal compositions comprising plant extracts that are non-toxic. However, there have been no successful attempts in to achieve such formulation that is non-toxic and highly efficacious.

There is abundant prior art literature relating to synergistic combinations of neem oil and karanja seed oil in the inhibition of insects.

Indian Patent No. 253066 relates to an herbal insecticidal formulation consisting of synergistically effective combination of tobacco dust extract, cold press vegetable oils from non-edible trees (preferably neem and karanj) either singly or in combination, pitch residue of essential oil and an appropriate amount and emulsifier. However, the said composition makes use of tobacco dust which is readily absorbed by the human body tissues resulting in respiratory tract diseases.

A research article titled, 'Synergistic action of neem and karanj to aphids and mites' published in Journal of Entomological Research,31 (2): 121-124, June 2007 authored by Vishal K et al. discloses the activity of a methanolic extract of neem (Azadirachta indica L.) and karanj (Pongamia pinnata Pierre) oil enriched in azadirachtin and karanj in respectively in combination against Tetranychus species and chrysanthemum aphid Macro siphoniella sanborni. Even though the synergistic action of neem oil and Pongamia oil is established by researchers Kumar. K et al, the composition disclosed in the research article when tested against aphids and mites showed minimum inhibition of the insects.

Therefore, there is a lasting need in the art to provide a bio-pesticidal composition with higher insecticidal potential when compared to the prior art literature that emphasize the use of the two active principles, i.e. neem oil and karanja oil. Further, prior art literature does not focus on blending potassium salts of fatty acid with tree seed oils to obtain a stable solution with higher solubility efficiency in distilled water.

Accordingly, the present inventors have provided a bio-pesticide product formulation that has high efficacy and which is prepared without the use of toxic organic solvents, thereby circumventing issues relating to eutrophi cation and bio- accumulation in the natural environment.

OBJECT OF THE INVENTION:

It is an object of the present invention to provide an eco-friendly, biodegradable, insecticidal composition as a solution without using any toxic organic solvents.

It is another object of the present invention to provide a bio-pesticidal composition for controlling infestation in agriculture, plantations and granaries by insect pests.

It is yet another object of the present invention to provide a suitable technique to blend fatty acids with tree seed oils to obtain a stable solution with higher solubility efficiency in distilled water.

SUMMARY OF THE INVENTION:

In an aspect, the present invention provides a bio-pesticidal in the form of a solution comprising a Millettia pinnata tree seed oil, Azadirachta indica tree oil, an insect cuticle desiccant and an inert carrier material. In another aspect, the present invention provides a process for preparing the present bio-pesticidal composition, the said process comprising;

(a) adding 20% to 70% potassium salts of fatty acid to distilled water at a temperature ranging from about 50°C to 100°C followed by stirring the mixture at 500 to lOOOrpm for 30 minutes;

(b) adding about 10% to about 20% of neem oil and about 10% to about 20% of Pongamia oil to the mixture of step(a) successively, followed by stirring the mixture at 500 to lOOOrpm for 30 minutes;

(c) transferring the mixture obtained in step (b) to a gravity separation funnel and collecting the solution obtained to provide the bio-pesticidal composition.

In yet another aspect, the present invention provides a method for preventing and controlling infestation of crops, the said method comprising contacting the insect cuticle with an insect debilitating effective amount of the composition or by application of insect pest lethal concentration of the composition to crop, foliage or grains.

DETAILED DESCRIPTION OF THE INVENTION:

The invention will now be described in detail in connection with certain preferred and optional embodiments, so that various aspects thereof may be more fully understood and appreciated.

Geographical Sources of biological material: The tree seed oils of Millettia pinnata and Azadirachta indica were commercially procured from M/s Sun agro products, 4/187 A, Sakthi Nagar, Dasanaikenpatty, Salem 636201, Tamil Nadu, India from the market.

For the purposes of the present invention, Azadirachta indica is referred to its common name "neem" and Millettia pinnata is referred to its common name "Karanja oil" or "Pongamia oil". In a preferred embodiment, the present invention provides a bio-pesticidal composition comprising a combination of Millettia pinnata tree oil, Az dirachta indica tree oil, and an insect cuticle desiccant.

More preferably, the present invention provides a bio-pesticidal composition comprising a combination of Millettia pinnata tree seed oil, Azadirachta indica tree seed oil, and an insect cuticle desiccant.

In a further embodiment, the present invention provides the bio-pesticidal composition comprises an inert carrier material.

In the most preferred embodiment, the present invention provides a bio-pesticidal composition comprising

a) 1% to 99% vol/vol Millettia pinnata tree oil containing Karanjin;

b) 1% to 99% vol/vol of Azadirachta indica tree oil containing Azadirachtin; and

c) 1%) to 99% by vol/vol of insect cuticle desiccant.

In an embodiment, the present invention provides a bio-pesticidal composition comprising;

a) 10% to 20% by volume/volume Millettia pinnata tree oil containing Karanjin;

b) 10% to 20% by volume/volume Azadirachta indica tree oil; containing Azadirachtin

c) 30%) to 40%) by volume/volume of an insect cuticle desiccant; and d) water as a diluent in a concentration ranging from 10%> to 50%>.

The concentration of the active herbal ingredients facilitates an increase in the cross flow velocity and the influx concentration of the said active ingredients from the mixture oil fatty layer to the aqueous layer. In an optional embodiment, the present invention provides a bio-pesticidal composition further comprising;

a) 0.5-5% by volume of silicone oil.

b) 0.5-5% by volume of salicylic acid, and

c) 1-10%) by volume of alcohol monosaccharide.

In another preferred embodiment, the present bio-pesticidal composition is formulated in the absence of toxic organic solvents, water being the only diluent employed in the present composition.

In one embodiment, the present invention provides the insect cuticle desiccant to be selected from salts of fatty acid. The salts of fatty acid are selected from the group comprising laureate, myristate, palmitate, stearate, oleate, behenate, linoleate and ricinoleate. More preferably, potassium salts of fatty acid are used. Accordingly, the potassium salts of fatty acids is selected from the group comprising potassium laureate, potassium myristate, potassium palmitate, potassium stearate, potassium oleate, potassium behenate, potassium linoleate and potassium ricinoleate. Fatty acids penetrate the insect cuticle and disrupt the insect cell membrane and surface lipoproteins. The cell contents leak out causing the insect to dehydrate and die. The fatty acids are selected from the group comprising fatty acids having carbon content in the range of C12 to C22. Potassium salts of fatty acids are prepared by adding potassium hydroxide to fatty acids present in animal fats and in plant oils.

The inert carrier is a diluent which is preferably water and constitutes 50% of the total weight of the formulation.

In another embodiment, the present bio-pesticidal composition possesses inhibitory activity against insects of the order selected from the group consisting of Hemiptera, Lepidoptera, Coleoptera and Diptera. More preferably, the bio-pesticidal composition is active against; (i) Nymphs and adult insects selected from the Order Hemiptera, and

(ii) 1^st instar, 2^nd instar and 3^rd instar larval stage of insect selected from Order Lepidoptera.

Accordingly, the present bio-pesticidal composition has inhibitory activity against a range of species selected from the following orders;

(a) Lepidoptera order selected from the group comprising of but not limited to Chilo partellus, Spodoptera exigua, Helicoverpa armigera

(b) Hemiptera order selected from the group comprising of but not limited to Bemisia tabaci, Aphis gossypii.

(c) Acaricidal activity against red spider mites group but not limited to Tetratnychus sp.

The present composition exhibits a mortality %ranging from about 70% to about 100% against a vast range of insect species.

In yet another embodiment, the present invention provides the present bio-pesticidal composition to be formulated as liquid formulations selected from the group consisting of a solution, suspension, emulsion or an emulsifiable concentrate, aerosol formulations and lyophilized formulations.

The emulsifiable concentrate formulation is prepared comprising the active herbal ingredients, and an agent that allows the formulation to be mixed with water to form an emulsion. The concentrates may be applied using different types of application equipment such as hydraulic sprayers, low volume ground sprayers, mist blowers and low volume air-craft sprayers.

The present formulation is not solely restricted to aforesaid carriers, biologically safe solvents or carriers that facilitate dissolution of the active herbal ingredients, or solid chemicals are incorporated in the present formulation to aid in the delivery of the active ingredient, and adjuvants often help make the pesticide adhere to or spread out on the application surface (i.e., plant foliage).

In one optional embodiment, the present invention provides the present composition to comprise an alcohol of monosaccharide selected from the group comprising sorbitol, mannitol, xylitol, maltitol, maltitol syrup, lactitol and erythritol.

The synergistic combination comprising sugar alcohol such as mannitol increased the attraction of insects to come in contact with the leaves sprayed or diet containing the present composition, thereby resulting in active ingredients acting upon the insect gut, spiracles of the insect blocking the respiration of insects and killing insects by asphyxiation.

Further, addition of 0.5% to 5% silicone oil and 0.5% to 5% salicylic acid increased insect pest mortality rate as observed in Tables 1 to 6.

Salicylic acid increases the efficacy of bio-pesticide composition on plant trials by presenting stress tolerance. Alcohol monosaccharide as an insect phagostimulant was observed to facilitate the insects to feed comprising the present pesticide composition.

In yet another preferred embodiment, the present invention provides a process for preparing the present bio-pesticidal composition, the said process comprising;

(a) adding 30% to 40% potassium salts of fatty acid to distilled water at a temperature ranging from about 50°C to 100°C followed by stirring the mixture at 500 to lOOOrpm for 30 minutes;

(b) adding about 10% to about 20% of neem oil and 10% to about 20% of Pongamia oil to the mixture of step(a) successively, followed by stirring the mixture at 500 to lOOOrpm for 30 minutes; (c) transferring the mixture obtained in step (b) to a gravity separation funnel and collecting the solution obtained to provide the bio-pesticidal composition.

The gravitational phase separation technique with a unique ratio of water, an amphoteric molecule and the neem and karanja oil mixture are advocated as essential in the preparation of a stable, efficient and environmentally safer insecticide product in the present invention.

In yet another optional embodiment, the present invention provides sequentially adding about 1 to about 1% silicone oil, about 1% to about 5% alcohol monosaccharide, about 1% to about 5% salicylic acid to the mixture obtained in step (b) followed by stirring the mixture at 500 to lOOOrpm for 30 minutes and then subjecting the mixture to gravitational phase separation to obtain the present composition.

In one preferred embodiment, the present invention provides a method for preventing and controlling infestation of crops, the said method comprising contacting the insect cuticle with an insect debilitating effective amount of the present composition or by application of lethal concentration of the composition to crop, foliage or grains.

Accordingly, the present composition in a liquid formulation may be applied by spraying the same in an amount ranging from about 500 ml to about 1000 ml per acre of crops in an agriculture filed that is infested or prone to insect infestation. Further, the present composition in a suitable formulation is sprayed in safe concentrations onto the inner surfaces of storage containers and grains. Advantages of the present invention:

1. The present inventors have circumvented the issue of release of agricultural effluents in the run-off by avoiding the use of toxic organic solvents in the present bio-pesticide composition;

2. Due to the absence of interfering chemical compounds in the present composition, the same may be used in the preservation of grains meant for human consumption.

Examples: Following examples are given by way of illustration therefore should not be construed to limit the scope of the invention.

Example 1: Insecticidal activity of bio-pesticidal composition

The insecticidal activity of the bio-pesticidal composition of the present invention and that of the active components when used alone was determined against nuisance causing insect pests in agriculture such as Whiteflies, Aphids, Mites, Tomato fruit borer, Maize stem borer and Beet army worm. About thirty (30) insects from each species were evaluated or treated with claimed composition and concentration and thirty (30) untreated insects were maintained as a control set. The below mention formulations are mixed with 1 liter distilled water.

Example 1(a): Insecticidal activity of bio-pesticidal composition against Aphis gossypii

The cotton aphid has a wide host range. Among cucurbit vegetables, it can affect watermelons, cucumbers, cantaloupes, squash and pumpkin.

Other vegetable crops attacked include pepper, eggplant, okra and asparagus. It also affects citrus, cotton and hibiscus. Aphis gossypii was treated with tree seed oils of Pongamia oil and Neem oil individually to obtain inhibition in insect growth as less as 40% and 60%, respectively. Treatment 10-(T10) which constituted the composition of the present invention caused insect inhibition of upto 100%. Table 1: Mortality% of Aphis gossypii treated with compositions Tl - T16

T: Treatment

PL: Potassium Laureate

Example 1(b): Acaricidal activity of bio-pesticidal composition against

Tetranychus

Nymphs and adults of the Cotton red spider mite belonging to the Tetranychus genusform fine a web on the under-surface of leaves and suck cell sap. Lamina starts reddening from its attachment to the petiole and extends to the entire lamina. The species attack Brinjal, Tomato, Pigeon pea etc. Individual seed oils used in the experimental treatment studies showed Tetranychus inhibition as less as 27% and 35%) when neem oil and karanja oil were used respectively, compared to inhibition of upto 85%o when treated with the present composition. Table 2: Mortality% of Tetranychus sp.treated with compositions Tl - T16

Example 1(c): Insecticidal activity of bio-pesticidal composition against Bemisia tabaci

Bemisia tabaci, also called as the silverleaf whitefly, is a parasite that feeds off of its host plants by penetrating the phloem surface of the leaf with its mouth and sucking out nutrients. Affected areas of the plant may develop spots, wilt and whither, or lose leaves. The white flies additionally secrete a sticky substance which can induce the growth of mold on plant surfaces thereby reducing the ability of the plant to absorb light leading to less growth and lower crop yield. The silverleaf whitefly also acts as a vector for plant disease transmitting viruses such as lettuce infectious yellows virus, tomato yellow leaf curl virus, and African cassava mosaic virus. The tree seed oils of Pongamia oil and neem oil when used individually showed comparatively lesser mortality% compared to the treatment composition (T10) of the present invention which showed 100% inhibition of the silverleaf whitefly.

Table 3: Mortality% of Bemisia tabaci treated with compositions Tl - T16

Example 1(d): Insecticidal activity of bio-pesticidal composition against Helicoverpa armigera

Helicoverpa armigera also called as cotton bollworm is a highly polyphagous species. The most important crop hosts are tomato, cotton, pigeon pea, chickpea, rice, sorghum and cowpea. The present composition displayed an effective reduction in the H. armigera growth of upto 60% and 75% when used in quantities of 5ml/L and lOml/L, respectively. Table 4: Mortality% of Helicoverpa armigera treated with compositions ΊΊ-

T16

Example 1(e): Insecticidal activity of bio-pesticidal composition against Spodoptera exigua

Spodoptera exigua also called as the beet armyworm or small mottled willow moth. The wide host range of the beet armyworm includes asparagus, beans and peas, sugar and table beets, celery, cole crops, lettuce, potato, tomato, cotton, cereals, oilseeds, tobacco, many flowers, and a multitude of weed species(Robinson, G. S., et al 2010. HOSTS - A Database of the World's Lepidopteran Hostplants. Natural History Museum, London. "). Spodoptera exigua insects when treated with the present treatment composition (T10) showed a maximum inhibition of upto 95%. Table 5: Mortality% of Spodoptera exigua treated with compositions Tl - T16

Example 1(f): Insecticidal activity of bio-pesticidal composition against Chilo partellus

C. partellus attacks several grass species which can be both cultivated and wild.

Cultivated crop hosts include but are not limited to maize, sorghum, pearl millet, rice, and sugarcane. Wild hosts include elephant grass (Pennisetum purpureum), reeds (Phragmites) and vossia (Vossia cuspidate).

Table 6: Mortality% of Chilo partellus treated with compositions Tl - T16

Treatments Treatment composition Mortality %

5 ml/L 10 ml/L

Tl Pongamiaoil (40%) + Isopropanol (10%) 10 15

T2 Neem oil (40%) + Isopropanol (10%) 15 25 T3 Pongamia oil (40%) + Isopropanol (10%) +Silicone oil 10 15

T4 PL (40%) 15 25

Τ5 Neem oil (40%) + Isopropanol (10%) +Silicone oil (0.5%) 17 25

Τ6 PL (40%) + Silicone oil (0.5%) 5 27

Τ7 PL (40%) + Pongamia oil (20%) + Silicone oil (0.5%) 32 40

Τ8 PL (40%) + Neem oil (20%) +Silicone oil (0.5%) 35 47

Τ9 PL (40%) + Neem oil (20%) + Pongamia oil (20%) + Silicone

oil (0.5%) +Salicylic acid (0.5%) 62 75

T10 PL (40%) + Neem oil (25%) + Pongamia oil (25%) 60 75

T11 PL (40%) + Neem oil (20%) + Pongamia oil (20%) + Silicone 62 74 oil (0.5%) + Salicylic acid (0.5%) + Mannitol (5%)

T12 Isopropanol (10 %) + Silicone oil (0.5%) 0 0

T13 Isopropanol (10 %) 0 0

T14 Salicylic acid (0.5%) 0 0

T15 Mannitol (5%) 0 0

T16 Distilled water 0 0

Example 2: Process for preparation of the present composition

400 ml of 40% of potassium salts of fatty acid was added to distilled water maintained at a temperature ranging of 75°C followed by stirring the mixture at lOOOrpm for 30 minutes. To the aforesaid mixture 200 ml of 25% of neem oil and 200ml of 25% of Pongamia oil were added successively, followed by stirring the mixture at lOOOrpm for 30 minutes. The entire mixture was later transferred to a gravity separation funnel and the solution obtained was collected to provide the bio insecticidal composition.

Claims

We claim,

1. A bio-pesticidal composition in the form of a solution comprising;

a) Millettia pinnata tree oil containing Karanjin in a concentration ranging from 10% to 20% volume by volume;

b) Az dirachta indica tree oil containing Azadirachtin in a concentration ranging from 10% to 20% volume by volume;

c) a salt of fatty acid an insect cuticle desiccant in a concentration ranging from 30%) to 40%) volume by volume; and

e) water as a diluent in a concentration ranging from 10%> to 50% by volume of water.

2. The bio-pesticidal composition as claimed in claim 1, wherein the insect cuticle desiccant is selected from a potassium salt of fatty acid.

3. The bio-pesticidal composition as claimed in claim 2, wherein the said potassium salt of fatty acid is selected from the group comprising laureate, myristate, palmitate, stearate, oleate, behenate, linoleate and ricinoleate.

4. The bio-pesticidal composition as claimed in claim 1, the said composition optionally comprises;

a) silicone oil in a concentration ranging from 0.5%to 5% by volume;

b) salicylic acid in a concentration ranging from 0.5% to 5% by volume; and c) an alcohol monosaccharide in a concentration ranging from 1% to 10% by volume.

5. The bio-pesticidal composition as claimed in claim 4, wherein the alcohol monosaccharide is selected from the group comprising sorbitol, mannitol, xylitol, maltitol, maltitol syrup, lactitol and erythritol. A process for preparing the bio-pesticidal composition as claimed in claim 1, the said process comprising;

(b) adding 10% to 20% of neem oil and 10% to 20% of Pongamia oil to the mixture of step(a), followed by stirring the mixture at 500 to lOOOrpm for 30 minutes;

(c) transferring the mixture obtained in step (b) to a gravity separation funnel and collecting the solution obtained.

The process for preparing the bio-pesticidal composition as claimed in claims 4 and 6, wherein the said process comprises optionally combining 0.5% to 1% silicone oil, 1% to 5% alcohol monosaccharide, 0.5% to about 5% salicylic acid to the mixture obtained in step (b) followed by stirring the mixture at 500 to lOOOrpm for 30 minutes and subjecting the mixture to gravitational phase separation to obtain a solution.