Project Progress Report:Implementation of the IPM program using weaver ants as a major component for cashew growers in Vietnam - MS7 " ppt

Data obtained from the field experiments and field surveys showed that • The common insect pests damaging flushing terminals, cashew apples and/or nuts were tea mosquito bugs, shoot bore

Ministry of Agriculture & Rural Development

Project Progress Report

029/05VIE:

Implementation of the IPM program using weaver ants as

a major component for cashew growers in Vietnam

MS7: Research/technical Report

Renkang Peng, Keith Christian, La Pham Lan and Nguyen Thanh Binh

31 July 2008

1 Institute Information

Project Name Implementation of the IPM program using weaver

ants as a major component for cashew growers in Vietnam

Vietnamese Institution Institute of Agricultural Science of South Vietnam

Vietnamese Project Team Leader Mr La Pham Lan

Australian Organisation Charles Darwin University

Australian Personnel Prof Keith Christian and Dr Renkang Peng

Date commenced February 2006

Completion date (original) January 2009

Completion date (revised)

Reporting period July 2008

Contact Officer(s)

In Australia: Team Leader

Name: Keith Christian Telephone: 61 8 89466706

Position: Professor Fax: 61 8 89466847

Organisation Charles Darwin

University Email: keith.christian@cdu.edu.au

In Australia: Administrative contact

Name: Jenny Carter Telephone: 61 08 89466708

Position: Research Manager Fax: 61 8 89467199

Organisation Charles Darwin University Email: jenny.carter@cdu.edu.au

In Vietnam

Name: La Pham Lan Telephone: 84 0913829560

Position: Head of Plant Protection

Department

Fax: 84 8 8297650

Organisation Institute of Agricultural

Science of South Vietnam

Email: lphlan@yahoo.com

Summary

To assist our cashew IPM TOT training program, field experiments, field surveys and observations, laboratory experiments and rearing were conducted in Binh Phuoc, Dong Nai and Dak Lac provinces between July 2006 and March 2008

Data obtained from the field experiments and field surveys showed that

• The common insect pests damaging flushing terminals, cashew apples and/or nuts were tea mosquito bugs, shoot borers, coreid bugs, thrips, apple-nut borers, leaf rollers, leaf miners, aphids and mealy bugs, among which tea mosquito bugs, shoot borers, leaf rollers and apple-nut borers were the major pests during the flowering and fruiting period The branch borer and the stem-root borer were the major pests damaging branches and trunks

• Weaver ants were similar to insecticides for controlling a range of insect pests, such as tea mosquito bugs, shoot borers, apple-nut borers, leaf rollers and leaf miners

• Cashew yields were similar between the IPM plot and the farmer’s plot, but nut quality was higher in the IPM plot than in the farmer’s plot because of the foraging behaviour of weaver ants

• Mealy bugs and aphids, that are currently determined to be minor pests, were unlikely to become major ones after the main pests are controlled by weaver ants A total of 12 species of natural enemies of aphids and 9 species of natural enemies of mealy bugs were determined, and these natural enemies were more frequently seen in the IPM plot than in the farmer’s plot, showing that when weaver ants were present, mealy bugs and aphids were present, and predators and parasitoids of these pests were also present, resulting in very little damage

to the cashew crop

• The key to successfully manage the IPM plot was to keep weaver ant

populations high and stable The boundary fighting between weaver ant colonies and the competition between weaver ants and other ant species were determined to be very important for the reduction of weaver ant populations Solutions for these competitive interactions were provided and discussed Data obtained from field observations, laboratory experiments and rearing showed that

• A soft chemical (Abamectine) was effective in controlling thrips, on which weaver ants have a little effect, and it was not harmful to weaver ants

• The bio-ecology of the branch borer and the stem-root borer were extensively studied Based on their ovipositing behaviour, initial damage symptoms and their life cycles, an integrated management strategy for each of the pests was recommended These strategies include three components (monitoring,

removal of young larvae based on initial damage symptoms, and chemical injection)

• Control strategies developed for thrips, branch borers and stem-root borers are compatible with the other components of the cashew IPM program

Based on the above results and general farming practice, a cashew IPM program which is suitable for cashew growing conditions in Vietnam has been developed and

is described in Appendix 1

Introduction

To assist our cashew IPM TOT training program, field experiments, field surveys and observations, laboratory experiments and rearing were conducted in Binh Phuoc, Dong Nai and Dak Lac provinces (the three biggest cashew growing provinces in Vietnam) between July 2006 and March 2008 The field experiments were conducted

in three demonstration orchards, each of which was divided into two plots: a farmer’s plot that was managed with chemical insecticides, and an IPM plot that was managed

by using the weaver ants (Oecophylla smaragdina) The field surveys were also

conducted in three orchards at different time of the cashew developmental stage At each orchard, the main insect pest damage was assessed in tree groups: trees with weaver ants, trees with other species of ants, and trees without ants The objectives of the field experiments and surveys were:

(1) letting TOT trainees observe and assess the main cashew insect pests and diseases (morphs, damage symptoms and life history) and their natural

enemies at different cashew developmental periods, and make comparisons between the farmer’s plot and the IPM plot,

(2) letting TOT trainees assess the effective control of the main insect pests by the most important bio-control agent - weaver ants,

(3) demonstrating how to use weaver ant colonies properly in cashew orchards, (4) demonstrating how to use different farming strategies at the different periods

of the year to grow healthy cashews, and

(5) collecting technical data to comprise the cashew IPM curriculum and the cashew IPM photo book

This report will summarise the effectiveness of weaver ants in controlling the main cashew insect pests, which directly damage flushing terminals, apples and nuts, and their effect on cashew yield and nut quality through comparisons between the farmer managed plots and the IPM plots and between trees with weaver ants and trees

without the ants

The following problems have been addressed during this period of the project:

(1) The branch borer (Rhytidodera integra) and the stem-root borer (Plocaederus

obesus) larvae cause the damage inside branches and the trunk, often resulting

in the death of main branches or even the whole tree Our preliminary

observations revealed that although weaver ants can catch or repel some adults from trees, they have no ability to control the larvae when they bore into branch or tree trunk In order to develop control methods that can manage the pests without negative effect on weaver ants, the bio-ecology for each of these two pests in southern Vietnam is needed However, no such information is available

(2) Thrips (Rhynchothrips sp and Scirtothrips dorsalis) that damage cashew

flowers, apples and nuts are not the main pests in insecticide control orchards

because insecticides used to control tea mosquito bugs (Helopeltis antonii and

H theivora), shoot borers (Alcidodes sp) and flower caterpillars also control

thrips However, the use of weaver ants is incompatible with the use of toxic insecticides Thrips damage on apples and nuts is increasing in some areas Weaver ants can reduce the thrips populations, but they cannot reduce the thrips damage below the economic injury level Therefore, it is necessary to find locally available low toxic insecticides that are effective in controlling the thrips, but that are not harmful to weaver ants

(3) Weaver ants have a mutual relationship with aphids (Toxoptera sp and Aphis

gossypii) and mealy bugs (Dysmicoccus brevipes and Ferrisia virgata), many

cashew growers are concerned about whether these minor insect pests will become major ones after the weaver ant is used The results from our research

in different cashew growing regions show that aphids and mealy bugs in cashew orchards with weaver ants are unlikely to become major insect pests Their populations can be naturally reduced by their natural enemies on which weaver ants have limited effect To demonstrate this relationship for TOT trainers and cashew farmers, apart from our regular monitoring on these pests between the farmer’s plot and the IPM plot at our demonstration orchards, determination of natural enemy species of aphids and mealy bugs in cashew orchards is important This work has never been done in Vietnam

Extensive field observations, laboratory experiments and rearing were conducted in Hong Loc Centre to understand the behaviour and the life cycle of the branch borer and the stem-root borer, to select locally available soft chemicals to control thrips, and

to determine natural enemy species of aphids and mealy bugs The results from this work will also be summarised in this report together with a discussion of how the suggested control methods of these pests fit the cashew IPM program, which uses weaver ants as a major component

Materials and methods

Field experiments

Three long-term field experiments were conducted in three demonstration orchards:

Mr Ty’s orchard in Dong Phu District of Binh Phuoc province, Hong Loc Centre orchard, and Mr Bi’s orchard in Trang Bom District of Dong Nai province

Mr Ty’s orchard

This orchard has about 2 ha of cashew trees grown from seeds To limit the effect of soil nutrition, half of this orchard was equally divided into two plots across the slight slope: farmer’s plot (70 trees) and IPM plot (70 trees) Around the IPM plot, a row of cashew trees was used as a buffer zone For insect pest control, chemical insecticides were used in the farmer’s plot, and sprays were done by the orchard owner based on his own experience In the IPM plot, weaver ants were used, and they were managed

by an experimentalist The other farming activities, such as weeding, pruning,

fertilizer application and the use of fungicides, were done the same for the farmer’s plot and the IPM plot and were conducted by the orchard owner

Due to regular insecticide use, this orchard had no weaver ants before it was used as our demonstration orchard To establish and manage weaver ant colonies in the IPM plot, the following 5 steps were followed:

(1) the dominant ant species in each tree of the plot was determined We found all

the trees were fully occupied by the crazy ant (Anoplolepis gracilipes), which

is a competitor with weaver ants;

(2) to reduce the crazy ant populations, a contact-killing insecticide (Motox ®) was sprayed at the tree bases while fallen leaves were raked to expose the ant nests;

(3) a week later, about 5 - 10 trees were grouped together with twisted polystrings

if their side branches were not attached in preparation for receiving new weaver ant colonies Due to the fighting behaviour of weaver ants between colonies, each group of trees received only one colony;

(4) a total of 10 weaver ant colonies were transplanted to the trees at a rate of 4 –

5 nests /tree in November 2006; and

(5) fresh minced fish meat was provided to each ant colony during the period of tree dormancy

Two weeks later and onwards after weaver ant colonies were transplanted, all the ant colonies were regularly monitored Weaver ant abundance was expressed as a percent per tree by the following method: (the number of main branches with a weaver ant trail in a tree / the number of the main branches in the tree) x 100 Weaver ants on a tree were treated as“Abundant”, if > 50% of the main branches had ant trails

The major insect pest damage between the two plots was regularly monitored The damage symptoms for each of the major insect pests on flushing shoots, flowers and nut was easily recognized and separated in the field by experimentalists who were preliminarily trained with such knowledge All the trees in each plot were numbered

in sequence Two-weekly monitoring occasions were also numbered in sequence In each plot, trees with odd numbers were inspected in odd numbered weeks, and trees with even numbers were inspected in even numbered weeks, so that freshly damaged shoots would not be repeatedly counted (because soft foliar or floral flushes were

hardened before the next monitoring occasion) Preliminary observations suggested that all the main insect pests were more active in the lower tree canopy than in upper levels Therefore, the monitoring was concentrated in the lower level of the tree canopy For each tree, we recorded the total number of flushing shoots (including foliar or/and floral flushing terminals) and the number of freshly damaged shoots by each major pest, and percent damage was calculated

The cashew yields were measured in each plot one week before harvest by the following formula: total numbers of nuts counted on the half canopy of each tree on the same side × canopy score Four canopy scores (1, 1.33, 2 and 4) were used based

on the size and thickness of each tree canopy: score = ‘1’, if the canopy was 100% goodness (the canopy being biggest and thickest); score = ‘1.33’, if the canopy was 75% goodness; score = ‘2’, if the canopy was 50% goodness; score = ‘4’, if the canopy was 25% goodness Cashew nut quality was generally assessed on site based

on overall nut appearance: shine and clean skin

Hong Loc Centre orchard

The orchard is next to Dong Nai TOT training Centre, which is very convenient for TOT trainees to do field experiments and observations The orchard had ten cultivars, each of which occupied one row, and each row was divided into two parts (farmer’s part and IPM part) A total of 10 farmer’s parts made a farmer’s plot, with 67 trees A total of 10 IPM parts made an IPM plot, with 71 trees There were 14 existing weaver ant colonies randomly distributed in this orchard In the farmer’s plot, weaver ants on most of the trees were manually removed to the trees without weaver ants in the IPM plot, and then chemical insecticides were used to remove the remaining ants to make sure no weaver ants were in the farmer’s plot In the IPM plot, after existing weaver ant colonies were combined with the transplants from the farmer’s plot, almost every

tree had weaver ants Apart from weaver ants, we also found ghost ants (Tapinoma

unidentified black ant in this orchard, but we did not bait them because they were not found to compete with weaver ants The experiment began in September 2007 The field management, weaver ant monitoring, insect pest monitoring, and yield, and nut quality assessment followed the same protocol as Mr Ty’s orchard (see above)

Mr Bi’s orchard

This orchard has two blocks next to each other, and each block is about one ha Block

1 was used from September 2006 to July 2007, and because of the disturbance of the site caused by the owner, block 2 was used from September 2007 to May 2008 In each block, 120 cashew trees of the same cultivar and similar size were used, and they were divided into two plots (farmer’s plot – 60 trees and IPM plot – 60 trees) Due to regular insecticide use, cashew trees in this orchard had no weaver ants, but they were

occupied by mud-nesting crematogaster ants (Crematogaster sp), ghost ants and an

unidentified black ant

In 2006, to establish weaver ant colonies in the IPM plot, these ant species were baited by an ant bait (fresh minced fish meat mixed with Regent®) A week after baiting, these ant populations were greatly reduced, and weaver ant colonies were transplanted into the IPM plot in early December 2006 The field experimental design, field management, weaver ant monitoring, insect pest monitoring and yield

assessment followed the same protocol as Mr Ty’s orchard (see above)

Surprising results were obtained from December 2006 to July 2007, showing lower cashew yield and nut quality and heavier pest damage on foliar and floral shoots in the IPM plot compared to the farmer’s plot Through a detailed examination

in April 2007, the following phenomenon was observed:

(1) boundary fighting between weaver ant colonies and weaver ants dispersal to orchard boundary trees resulting in 30% of the trees being without weaver ants, and 30% of the trees had very low numbers of weaver ants (the ant abundance being < 30%) These trees were either fully or partly occupied by ghost ants, and they were heavily damaged by tea mosquito bugs, shoot borers and fruit-nut borers

(2) on the remaining 40% of the trees, weaver ants were abundant on tree trunks and the main branches, but they did not forage on aphid-free foliar and floral shoots, resulting in the heavy damage on flushing shoots, flowers and

developing nuts by tea mosquito bugs, shoot borers and fruit-nut borers The first phenomenon was mainly due to the experimentalist who lacked the

experience in managing weaver ant colonies Ghost ants are very small (about 1.1 mm), and they were incorrectly thought not to be very competitive with weaver ants For the second phenomenon, 7 field surveys were conducted in different types of cashew orchards with weaver ants together with interviews of the orchard owners for information about farming practice Through comparisons, it seemed that heavy leaf fertilizer sprays (3 applications done in the IPM plot between December 2006 and January 2007) may suppress or change the level of extra floral nectar secreted by flushing terminals, which made them unattractive to weaver ants

In 2007, therefore, more attention was paid to weaver ant colony management and no leaf fertilizers were used in the IPM plot The other management, such as baiting other ant species, weaver ant transplantation, weaver ant monitoring, insect pest monitoring and yield assessment, followed the same protocol as in the first year Field survey

A total of 6 field surveys were done in three cashew orchards: Mr Quang’s orchard in Dong Xoai district of Binh Phuoc province, Mr Be’s orchard and Mr Sau’s orchard in Trang Bom District of Dong Nai province

Mr Quang’s orchard

This orchard had 60 cashew trees grown from seeds (14 trees over 10 years old and 46 trees about 3 years old) This orchard was surrounded by two patches of mahogany trees and cassava crop Because no insecticides were used, there were three existing weaver ant colonies on big cashew trees and mahogany trees, and the ants had

dispersed to some of the young cashew trees when we did the first survey in July

2006 As big cashew trees were too tall to make an accurate assessment of the main pest damage, each survey was concentrated on the 46 small trees On each survey, all the 46 trees were inspected, and for each tree, we recorded the dominant ant species

on the tree, the total numbers of flushing foliar and/or floral terminals on the tree and the number of terminals damaged by each major pest, and the percentage damage was calculated A total of three surveys were done in this orchard: July 2006, December

2006 and April 2007

Mr Be’s orchard

Two surveys were done in this orchard which has several blocks of cashews The first survey was conducted in July 2006 in a block of about 3 ha In this block, trees were over 20 years old, but there were 18 young trees (about three years old) randomly growing among the big trees due to the replacement of the dead trees Insecticides were not regularly used in this block (about one or two times a year), and therefore, there were some existing weaver ant colonies on big trees, and they had dispersed to some of the young trees Because big cashew trees were too tall to make assessment

of the main pest damage, this survey was concentrated on the 18 small trees

The second survey was conducted in another block of the orchard in August

2007 in collaboration with a field practical of the TOT training This block was about one ha, and trees were 4 years old of similar size This block was closely surrounded

by old cashew trees (> 10 years) There were several weaver ant colonies on the big trees, and they had dispersed to some of the young trees A total of 50 young trees were surveyed

For each survey, the methods used were the same as in Mr Quang’ orchard

Mr Sau’s orchard

This is an abandoned orchard, and it had 53 medium sized cashew trees of unknown age There were three existing weaver ant colonies: one in the orchard, and another

two colonies originally on the Eucalyptus trees on the edge of the orchard, which had

dispersed to a few cashew trees A survey was done in July 2006 The survey methods used were the same as in Mr Quang’ orchard

Field observations and laboratory rearing

Field observations and laboratory rearing were conducted in Hong Loc centre, Hong Loc Centre orchard, Mr Sau’s orchard and some orchards in Dak Lac province The observations concentrated on the bio-ecology of the branch borer and the stem-root borer, including the behaviour of larvae and their life cycle This was done by

dissecting branches and stems at different cashew developmental periods The adult emergence, activity and oviposition were also observed in evenings

The laboratory rearing was concentrated on natural enemy species of aphids, mealy bugs and shoot borers

In order to find a suitable soft chemical that will reduce thrips populations on developing nuts, but will not be harmful to weaver ants, lab experiments were

conducted using the locally available soft chemicals using four treatments: developing nuts and apples with thrips were treated with Applaud, D.C Tron oils, Abamectine and water, respectively

Data analysis

For field experimental data analyses, on each monitoring occasion, two plots (farmer and IPM) were ranked, based on mean percentage damage by each major pest All the monitoring occasions in the flowering and fruiting period and in the dormant or leaf flushing period were separately compared by a non-parametric Friedman 2-way ANOVA by ranks using SYSTAT statistics software The percentage yield data and

field survey data were analysed by a Kruskal-Wallis one-way ANOVA by ranks to test for a difference between plots and between trees with or without weaver ants

Results

Field experiments

Mr Ty’s orchard

The weaver ant populations in the IPM plot were high and stable from December

2006 to July 2007, and the average ant abundance was over 80% (Fig 1) However, from August 2007 to January 2008, the ant populations gradually decreased from 70%

to 28% (Fig 1) This was mainly due to fighting between weaver ant colonies

7 Jul 14 Nov 24 Dec 4 Jan 12 Jan

statistically similar (P > 0.05; Table 1)

Table 1 The average number of flushing shoots per tree for the farmer’s plot and the

IPM plot during the period of pre-flowering flush and nut development (November – March), Binh Phuoc province, Vietnam

/tree + SD

Rank sum

Friedman two–way ANOVA Xr2 =3.600; df = 1; P = 0.058

Based on the monitoring data, the common insect pests in this orchard were

tea mosquito bugs, shoot borers, leaf miners (Acrocercops syngramma), aphids, the apple-nut borer (Nephopteryx sp), leaf rollers and branch borer The population

fluctuations in the IPM plot and the farmer’s plot for tea mosquito bugs, shoot borers, leaf miners and aphids, are shown in Figs 2, 3, 4, and 5, respectively

7 Jul 24 Dec 4 Jan 12 Jan

| 06 | - 2007 -| 08 |

Fig 2 Mean % foliar or floral flushing shoots damaged by tea mosquito bugs in the

farmer’s plot and the IPM plot at Binh Phuoc province, Vietnam

7 Jul 24 Dec 4 Jan 12 Jan

|-06-| -2007 -|-2008 |

Fig 3 The mean % flushing shoots damaged by shoot borers in the farmer’s plot and

the IPM plot at Binh Phuoc province, Vietnam

|-06-| -2007 -|-2008-|

Fig 4 The mean % shoots damaged by leaf miners in the farmer’s plot and the IPM

plot at Binh Phuoc province, Vietnam

7 Jul 24 Dec 4 Jan 12 Jan

|-06-| -2007 -| -2008 -|

Fig 5 The mean % shoots with aphids in the farmer’s plot and the IPM plot at Binh

Phuoc province, Vietnam

During the period of pre-flowering flush to nut development (November to March), the damage level of cashew flushing shoots, flowers or young nuts by tea mosquito

bugs, shoot borers, leaf miners, aphids and leaf rollers was similar between the

farmer’s plot and the IPM plot (P > 0.05; Figs 2-5; Table 2) However, the average level of developmental nuts damaged by the fruit-nut borer was lower in the IPM plot than in the farmer’s plot (P = 0.018; Table 2)

Table 2 The mean % shoots damaged by insect pests in the farmer’s plot and the IPM

plot of the demonstration orchard at Binh Phuoc province, Vietnam

Friedman two–way ANOVA Pest name Treatment Mean % shoots

damaged /tree + SD Rank sum Statistic

Tea mosquito

Xr2 = 0.400; df = 1; P = 0.527

Shoot borers

Xr2 = 0.400; df = 1; P = 0.527

The leaf miner

Xr2 = 0.111; df = 1; P = 0.739

Aphids

Xr2 = 0.111; df = 1; P = 0.739

*, Mann-Whitney U test is used

During the cashew dormant or leaf flush period (April to July), the damage on flushing shoots by tea mosquito bugs, shoot borers and leaf miners was significantly lower in the IPM plot than in the farmer’s plot (Figs 2-4; Table 3) However, the average level of shoots with aphids was more in the IPM plot than in the farmer’s plot (Fig 5; Table 3)

Table 3 The mean % shoots damaged by insect pests in the farmer’s plot and the IPM

plot during the tree dormancy or leaf flush period at Binh Phuoc province, Vietnam

Friedman two–way ANOVA Pest name Treatment Mean % shoots

damaged /tree + SD Rank sum Statistic

Tea mosquito

Xr2 = 8.000; df = 1; P = 0.005

Shoot borers

Xr2 = 8.000; df = 1; P = 0.005

The leaf miner

Xr2 = 4.500; df = 1; P = 0.034

Aphids

Xr2 = 8.000; df = 1; P = 0.005

In 2007, we missed the opportunity to assess the number of nuts on tree canopies before harvest However, after the harvest, the orchard owner told us that the nuts produced were cleaner and shinier in the IPM plot than in the farmer’s plot

In 2008, the assessment of the number of nuts on tree canopies was done one week before harvest, and it showed that the number of nuts per tree was significantly

higher in the farmer’s plot than in the IPM plot (Table 4) Based on regular

monitoring, we found that weaver ant populations in the IPM plot were very low (from 48% in December 2007 to 28% in January 2008; Fig 1), and the trees with low numbers of ants were heavily damaged by tea mosquito bugs and shoot borers during the flowering and fruiting time However, there were 20 trees which had reasonable numbers of weaver ants (the ant abundance was > 35%), and these were much less damaged by these pests When comparing the 20 trees in the IPM plot with the 70 trees in the farmer’s plot, there was no significant difference in the numbers of nuts per tree (Table 5)

Table 4 The average number of cashew nuts per half canopy in the farmer’s plot and

the IPM plot of the demonstration orchard at Binh Phouc province, Vietnam

Plot (Treatment) Mean number of nuts

/tree + SD

Number of trees

Rank sum Farmer (use insecticides) 558.3 + 380.3 70 5482.5 IPM (use weaver ants only) 431.5 + 336.3 70 4387.5 Mann-Whitney U test U = 2997.5; df = 1; P = 0.022

Table 5 The average number of cashew nuts per half canopy in the farmer’s plot and

the IPM plot of the demonstration orchard at Binh Phouc province, Vietnam

Plot (Treatment) Mean number of nuts

/tree + SD

Number of trees

Rank sum Farmer (use insecticides) 558.3 + 380.3 70 3200 IPM (use weaver ants only) 526.9 + 332.3 20 894

Mann-Whitney U test U = 7150500; df = 1; P = 0.880

Hong Loc Centre orchard

Fig 6 shows that weaver ant abundance was over 60%, and the ant populations were stable during the period of cashew flowering and fruiting (December 2007 – February 2008)

Fig 6 Average abundance

of weaver ants in the IPM plot

at Hong Loc Centre, Dong Nai

province, Vietnam

The average number of flushing shoots was more in the IPM plot than in the farmer’s plot, but they were not statistically different (Table 6)

0 20 40 60 80 100 120

22 Dec 07 5 Jan 08 19 Jan 08 2 Feb 08 16 Feb 08