DESC:
The present disclosure provides a pesticide formulation for coffee and tea plantations. In particular, the present disclosure provides an inorganic formulation for controlling Coffee White Stem Borer (CWSB) infestation in coffee and tea plantations.

BACKGROUND
Coffee production is the backbone of the economy of many developing countries in the tropics, and it ranks among the most valuable agricultural commodities in the world. Two species of coffee, arabica coffee (Coffea arabica L.) and robusta coffee (Coffea canephora Pierre), are cultivated on a commercial scale.
Several insect species have been recorded as pests of coffee plantations in Asian countries. Coffee white stem borer (Xylotrechus quadripes) is a menace in coffee estate specifically, for Arabica type of coffee plantation. The insect has a year-long life cycle of which nearly 80% is inside the plant. The phases, where this insect is out of the plant is in the adult phase (nearly 3 weeks life time) during which mating happens and the female lays as many as hundreds of eggs on the rough surfaces of the stems of the Arabica coffee. The eggs emerge into first instars in about 11 days which then start eating the bark and make inroad into the stem of the plant creating ridges. The circular path initially traced leads into a vertical downward movement of the insect for the next 8 months or more where they develop into an adult. With the faeces becoming a packing material for the path traced, the insect is, in fact, protected from both the ends and is therefore safe from any external stimuli. CWSB larvae produce galleries in the main stem and primary branches. CWSB larvae sometimes tunnel their way into the main root. After tunneling by a larva, under the bark region for about 2 months, a ridge develops on the surface of the stem, which is as an external symptom of borer attack. Consequently, the damaged plant withers, showing yellowing and wilting symptoms. Larvae tunnel in all directions in the stem, and each larva tunnels separately without interfering with the other. The severity of damage depends on the size of the larval population. An exit hole in the stem indicates the completion of the life cycle of the pest. It is found that about 84% of adults emerge from the main stem and 16% from the roots. Some infested plants survive for a long period, but produce empty fruits.
General practice recommended to avoid CWSB attack is to enable enough shading, wrapping the stems of coffee plant, lime coating, pheromone traps, rubbing the bark and smoothening the stem, and use of chlorpyriphos as a pesticide. However, in spite of all these efforts, the menace of CWSB has not come under control.
Shading can provide a bigger impact on the insect population but it is not a fool proof method to control CWSB. Wrapping the major primary and the main stem of the Arabica coffee plant will prevent the CWSB from laying eggs if the wrapping is absolutely well done. This is seen as a very effective way of preventing the insect fecundity on the plant. However, even if there is scope for one insect to access the stem through the wrapper, it becomes absolutely impossible to trace the extent of damage as monitoring is not possible due to the blocking wrap.
Rubbing the barks to remove the crevices is considered one of the effective methods for preventing the adult from laying the eggs on the stems. This is considered effective only if the infestation levels are low and the extent to which smoothening happens. However, even this method is not a fool proof method for pest control. Further, the rubbed barks make the plant susceptible for other infections.
Pheromone traps are used to trap one sex type of the CWSB. Since mating of white stem borers is a complicated process, pheromone traps is considered as one that has limited potential to control CWSB population.
As regards chemical pesticides, laboratory trials show that chlorpyriphos is more effective against eggs, while carbosulfan is more effective against the fifth-instar larvae, and a combination of chlorpyriphos and carbosulfan is effective against adults. Chlorpyriphos is more effective and less hazardous and is recommended for stem application during the peak emergence periods of CWSB. Such chemical pesticides are not biodegradable and environment friendly.

Applying lime on the ridges and crevices of the stem is one of the effective ways of preventing the eggs from being laid on the stems (since gaps and crevices are the place for egg laying by the adult). The high alkaline nature of lime prevents eggs from hatching and therefore prevents the CWSB population. In practice, since lime is not dispersible, it has to be mechanically applied with the help of a brush scrubbing through every part of the stem. Therefore, it is a labor intensive job and difficult to be considered as an effective estate practice.

Thus, there is a need for a formulation for controlling pests, specifically for coffee, which is inexpensive, easily dispersible and also does not suffer from the disadvantages of existing methods; and chemical toxicity to humans and the environment.

SUMMARY
A pesticide formulation is disclosed. The formulation comprises silica; a source of calcium; and water, wherein silica and calcium are in a concentration ratio of 1:1 to1:6.

DETAILED DESCRIPTION
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the disclosed composition, and such further applications of the principles of the invention therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
Reference throughout this specification to “one embodiment” “an embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in one embodiment”, “in an embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
The present disclosure provides a formulation (pesticide formulation) for controlling CWSB (pest/ insect) infestation in coffee plantations. In particular, the present disclosure provides a formulation for controlling CWSB infestation in coffee plantations comprising a source of calcium and silica.
In accordance with an embodiment, silica and the source of calcium are in a weight ratio range of 1:1 to 1:6 (w/w), preferably 1:3 to 1:5.
In accordance with an embodiment the pesticidal formulation has silica in a concentration range of 2 to 10 wt% of the formulation.
In accordance with an embodiment the pesticidal formulation has the source of calcium in a concentration range of 2 to 10 wt% of the formulation.
In accordance with an embodiment, the source of calcium is selected from calcium carbonate, lime, calcium oxalate and calcium oxide.
In accordance with an embodiment, the formulation comprises calcium carbonate and silica. In accordance with an embodiment, silica and calcium carbonate are in a weight ratio range of 1:1 to 1:6 (w/w), preferably 1:3 to 1:5.
In accordance with an embodiment, the formulation targets the adult pest and its eggs. The formulation possesses negative ions which facilitate rupture of the egg surface and silica provides dehydrating effect thereby acting as an ovicide.
In accordance with an embodiment, the material characteristics of both calcium and silica sources have been altered to enable water dispersibility. The silica and lime are in the particle size range of 100nm to 1000nm and free from any hydrophobic chemical moiety. The material characteristics can be altered to obtain individual water dispersible materials of calcium and silica respectively. In accordance with an embodiment, the individual water dispersible materials (of calcium and silica respectively) can be mixed with each other just before the application and normal practice of spraying is carried out for uniform application on coffee plantations.
In accordance with an embodiment, the formulation is in the form of a sprayable solution. In accordance with an embodiment, the formulation is in the form of a water dispersible concentrate.
In accordance with an embodiment, the formulation further comprises an adhesive which facilitates binding of the silica and lime to the stem which will help in reducing the washing away of silica and lime during rains. By way of an example, adhesive is DDL Fevicol.
The present disclosure also provides a method of preparation of the above disclosed formulation. Further, the present disclosure provides a method of application of the above disclosed formulation to coffee plantations.

Examples:
Example 1: The following table provides comparative data as regards application of the present formulation and the chemical pesticide (chlorpyriphos). Borer/ha indicates the number of plants infected with borers in 1 hectare of plantation and uprooted implies number of plants removed (uprooted) because of borer attack. Further, % indicates percentage of plants uprooted. Each round of tracing (inspection of the plantation) extends to nearly two months and there are 5 or 6 rounds in a year.
Table 1:

Example 2: Trial against CWSB during 2016/’17
CWSB Emergence season of adults of the borer is known as flight period. There are two peak flight periods i.e., one from April to May ie. Summer Flight period, which is short and the other from October to December ie. winter flight period, which is extended due to prevailing dry weather. However, emergence of beetles in small numbers are recorded during other months also. Cloudy and wet weather conditions delay the emergence of the beetles by a week or two.

ESTATE NAME Lime + Silica*
Area Sprayed (ha) Date of Spray
SUNTICOPPA
(North Coorg) Block – 09 (9.0 Ha) 07.05.2016 to 13.05.2016
JUMBOOR
(North Coorg) Block – 01 (18.10 Ha) 05.05.2016 to 02.06.2016
UBBAN (Bhagya)
(Sakleshpur) Block -05 (4.0 Ha) 03.06.2016 to 07.06.2016
TOTAL 31.10 Ha

- * - Dosage Dispersible Lime @ 26.7 kg + silica powder @ 6.7 Kg with @ 250gm of DDL Fevicol and final volume made to 200 litres

White stem borer is annual pest i.e. it will take ~ 1 year to complete the life cycle from Egg-Larva-Pupa-Adult. However, the treatment imposed during the winter flight period-2015. Observation will be continued till next winter flight period-2016. The treatment imposed during the summer flight period-2016: Observation will be continued till next summer flight period-2017.

Manual tracing: The WSB attacked plants can be easily detected by the presence of ridges on the generally smooth surface of the stem, which develops as a result of the feeding by the grub on the bark. The hatched out grub feed on the corky portion just under the bark for about 2 months and consequently the bark splits and appear as ridges on the stem. Later the larvae enters the main stem and spends rest of the life till it pupates and emerge as adult.

The process of monitoring the ridges made by the WSB larvae on the main stem and thick primaries is called as tracing which is carried out manually from plant to plant. Hence, tracing is an important cultural operation which is carried out round the year for identifying the infested stem, uprooting and destroying to eliminate the emergence of the adult. It is represented as borer infested plant uproot and destroyed, the data is given as borer per hectare. (i.e. borer/ha).
Thorough tracing is carried out mainly prior to the flight periods and during the flight periods, to avoid the re-infestation from the adult beetle.
To have systematic monitoring system, the following tracing period is formulated -
Period of Tracing:
• 1st Round Tracing (10th Feb -2016 to 10th April-2016) - Borer/ha.
• 2nd Round Tracing (11th April-2016 to 10th June-2016) - Borer/ha.
• 3rd Round Tracing (11th June-2016 to 20th Aug.-2016) - Borer/ha.
• 4th Round Tracing (21st Aug.-2016 to 10th Oct.-2016) - Borer/ha.
• 5th Round Tracing (11th Oct. -2016 to 10th Dec.-2016) - Borer/ha.
• 6th Round Tracing (11th Dec.-2016 to 9th Feb.-2017) - Borer/ha.
In the observation table (Table 2-4 below) manual tracing is control plot i.e., unsprayed area (None of the chemical/insecticide is applied).

Table 2

RESEARCH PROJECT ON WSB – Borer Tracing Details for the season-2016 (till 13.09.2016)
Time of treatment imposing winter flight-2015 (from 3rd week of Oct. to 4th week of Dec. -2015) and summer flight-2016 (1st week of May – 1st week of June-2016)

Bhagya Division – Ubban Estate (borer/ha.)
Sl. No. Treatment - Details Area of Trial 1st Round 2nd Round 3rd Round 4th Round Total
Block & Area in ha.
Borer /ha. Borer/ha. Borer/ha. Borer/ha. Borer/ha.
1 Silica + Calcium – Spray 5 – 4 Ha. 29 38 194 24 284
2 Manual tracing 6 – 8.2 Ha. 13 31 116 In progress 160

Table 3:
RESEARCH PROJECT ON WSB - Borer Tracing Details for the season-2016 (till 13.09.2016)
Time of treatment imposing winter flight-2015 (from 3rd week of Oct. to 4th week of Dec. -2015) and summer flight-2016 (1st week of May - 1st week of June-2016)
New Line Division - Jumboor Estate
Sl.No Area of Trial 1st Round 2nd Round 3rd Round 4th Round** Total
Treatment - Details Block & Area in ha.
Borer/ha. Borer/ha. Borer/ha. Borer/ha. Borer/ha.
1 Silica + Calcium - Spray Block - 01, 18.10 ha. 0.22 89 118 17 224
2 Manual tracing Block - 02, 16.30 ha. 0.70 9 45 In progress 54

Table 4:
RESEARCH PROJECT ON WSB - Borer Tracing Details for the season-2016 (till 13.09.2016)
Time of treatment imposing winter flight-2015 (from 3rd week of Oct. to 4th week of Dec. -2015) and summer flight-2016 (1st week of May - 1st week of June-2016)
Suntikoppa Estate (borer/ha.)
Sl. No. Area of Trial 1st Round 2nd Round 3rd Round 4th Round Total
Treatment - Details Block & Area in ha.

Borer/ha. Borer/ha. Borer/ha. Borer/ha. Borer/ha.
1 Silica + Calcium - Spray Block - 09, 9.0 ha. 5 11 39 In progress 55
2 Manual tracing Block - 10, 05.0 ha 2 24 26 In progress 52

Example 3:
To evaluate the efficacy of Lime and Silica on coffee WSB, trials were conducted in laboratory conditions in parallel to field application.
The infested stems were stored in enclosed well ventilated room to collect the emerging adult beetles. The collected adult insects were reared in the laboratory and allowed to mate and lay eggs. The eggs were collected every day, up to end of oviposition.
Application of Lime and Silica: Added 26.7 kg Lime slurry and 6.7 kg of Silica in 200 liters of water. Mixed the solution thoroughly for uniform distribution. Sprayed this solution on main stem and thick primaries of coffee plant using Knapsack Sprayer.
1st Method: The Lime and Silica sprayed stem at estate were brought to the laboratory. The eggs were allowed to hatch on treated stem and also on untreated stems. Stem were kept in the laboratory for observation.
OBSERVATION 1st Method:
• On treated stem, un-hatching of few eggs were observed, in few stems
• Hatched grubs were found crawling on the stem, struggling to feed / bite the stem
• It is observed that in untreated stem also, larva could not enter into the stem
2nd Method: Collected the neonate after hatching from the eggs and allowed on Lime + Silica treated and untreated stems and observed periodically.
OBSERVATION 2nd Method:
The neonates were crawling on stem and trying to enter in o the stem
• It was observed that the allowed grubs were dead on the stem after 1-2 days.
• Stems were periodically monitored for a month, and found that the larva has not entered the stem
• The same condition of larva not entering into the stem was observed in the untreated also.
Generally only 7 to 10% of the eggs will survive and hatch and neonate mortality is also observed depending on abiotic factor – rain, etc.
Hence, during 2016 season, the weak link for targeting WSB control is the eggs and larvae.

SPECIFIC EMBODIMENTS ARE DISCLOSED BELOW
A pesticide formulation comprising silica; a source of calcium; and water wherein silica and calcium are in a concentration ratio of 1:1 to1:6.
Such pesticide formulation(s), wherein silica and calcium are in a concentration ratio of 1:3 to 1:5.
Such pesticide formulation(s), wherein silica comprises 2 to 10 wt% of the formulation.
Such pesticide formulation(s), wherein the source of calcium comprises 2 to 10 wt% of the formulation.
Such pesticide formulation(s), wherein the source of calcium is selected from calcium carbonate, lime, calcium oxalate and calcium oxide.
Such pesticide formulation(s), wherein the formulation is sprayable solution or water dispersible concentrate.

INDUSTRIAL APPLICABILITY
The disclosed formulation is biodegradable, environmental-friendly and economical. The formulation provides promising bio-efficacy results against CWSB infestation in coffee plantations. The present disclosure provides a water dispersible sprayable formulation for an easy application to coffee plantation. Use of the disclosed formulation provides a sustainable way of controlling the CWSB attack and significantly brings down the CWSB attack on the coffee plantation. ,CLAIMS:We Claim:
1. A pesticide formulation comprising:
silica; a source of calcium; and water
wherein silica and calcium are in a concentration ratio of 1:1 to1:6.

2. A pesticide formulation as claimed in claim 1, wherein silica and calcium are in a concentration ratio of 1:3 to 1:5.

3. A pesticide formulation as claimed in claim 1, wherein silica comprises 2 to 10 wt% of the formulation.

4. A pesticide formulation as claimed in claim 1, wherein the source of calcium comprises 2 to 10 wt% of the formulation.

5. A pesticide formulation as claimed in claim 1, wherein the source of calcium is selected from calcium carbonate, lime, calcium oxalate and calcium oxide.

6. A pesticide formulation as claimed in claim 1, wherein the formulation is sprayable solution or water dispersible concentrate.

Dated this 28th day of September, 2015

Essenese Obhan
Of Obhan & Associates
Agent for the Applicant
Patent Agent No. 864