Improvement of vegetable production and postharvest management systems in Cambodia and Australia

Objective 1- To map supply chains and identify constraints to improvement of the Cambodian vegetable industry. (Cambodia)

Objective 2- To develop and demonstrate improved production and postharvest strategies that will underpin quality improvement and industry development (Cambodia and Australia)-

Objective 3- To improve R&D capacity in Cambodia in vegetable research, by ensuring maximum sharing of technology and know-how between Australian, AVRDC and Cambodian partners. (Cambodia, Australia and AVRDC).

Project activities commenced in October 2005 with a project planning workshop in Phnom Penh. All project partners including NSW Department Of Primary Industries (NSW DPI), Cambodian Agricultural Research and Development Institute (CARDI), Department of Agronomy and Agricultural Land Improvement (DAALI) and the Asian Vegetable Research and Development Centre (AVRDC World Vegetable Centre), were in attendance. The overall objective of this project is to improve the profitability and quality of Cambodian vegetables for the domestic market and to develop sustainable system improvements which can be readily adapted to other commodities and across the transport, storage, processing and export sectors.

At the workshop, dry season activities, including research station and field trials for tomatoes were designed, sites selected and survey questionnaires drafted. Several projects including the AusAID funded Agricultural Quality Improvement Project (AQIP), and non government organisations, including Intermediate Development Enterprises (IDE) and CARE Cambodia were also consulted, and joint activities including evaluations of the IDE low tech drip irrigation system were planned.

The dry season research trials included the following;
2 replicated tomato variety trials at DAALI and CARDI Research Stations
1 replicated on farm tomato variety trial
1 non replicated on farm tomato and chilli variety demonstration (shared with ADB/DAALI project)
1 replicated tomato nitrogen rate trial (DAALI)
1 non-replicated tomato drip irrigation trial (DAALI)
1 replicated processing tomato trial (Australia)

Postharvest assessments were carried out on the two replicated variety trials and the nitrogen trial.

The tomato variety entries included AVRDC varieties compared to existing grower varieties and as yet untested hybrid varieties, which were donated to the project by commercial seed companies. The trial sites varied in soil type and management system, and therefore the results gave good indication of suitability of the entries Some of the traditional varieties although relatively high yielding have poor shelf life, and other undesirable traits such as a tendency to split and crack.

In terms of fruit yield, the best performing open pollinated lines include CLN 1462A and CLN2764 and the traditional line K!, and the best performing hybrids Dalila (East West Seeds), HET2 (AVRDC) and Jetayu (Marco Polo Seeds). Overall, the best performing line at Dey Eth was CLN1462A, with the fruit yield significantly higher than all other varieties (at the 5% level), although higher plant populations probably influenced yield. Some of the commercial hybrid varieties, including Dalila and Jetayu performed consistently well at both sites. Further trials with these varieties would be required to determine if they perform consistently well enough to justify higher seed prices generally paid for hybrids. There was some variation between results at the CARDI and Dey Eth sites, the most notable being the poorer performance of CLN 1462A at CARDI.

Of the AVRDC lines, tomato breeder Dr. Peter Hanson suggests keeping CLN1462A and CLN2764 for next season's trials. He also noted that in Mali, researchers there had reported CLN2764 as Gemini virus resistant, which would important trait for Cambodia. Of the AVRDC hydrids, TLCV15 and HET2 could be dropped out as their performance was not exceptional when compared to some of the commercial hybrids such as Dalila.

The postharvest trial evaluated the fruit quality and postharvest storage life of the 13 tomato varieties. Varieties varied in their tolerance to postharvest disease with K1 having the highest disease ratings. In terms of sweetness, CLN2777-168-27-1-7 had a TSS of 5.9%, compared to 4.5% for K1. Postharvest storage life also varied with variety with CLN2764-99-13-18-10 having an average storage life of 11.1 days at 20C, compared with 8.8 days for K1. A complete analysis of the data is currently being undertaken

Ly Serievuth from DAALI has produced a draft tomato information sheet in Khmer language. It is based on the outcomes from the tomato variety work in the ACIAR project this year. Following thorough editing, this information sheet will be distributed to farmers, resellers and advisers working with vegetable crops. (A copy can be seen in Attachment 3 PDF file)

A replicated trial at Dey Eth Station comparing the effect of various rates of nitrogen on fruit yield and quality has been analysed. Fruit yields and postharvest assessment measures were taken from the various treatments which included rates of 0, 100, 120, 150 and 180 kgs/ha of nitrogen. The control treatment (0 kgs nitrogen/ha) has a significantly lower marketable yield than the treatments where nitrogen is applied. , Although there was no significant difference between the 100 to 180kgs/ha rates of nitrogen, there was a linear response to the level of nitrogen applied with higher levels of applied nitrogen increasing marketable yield. Early results from the postharvest analysis suggest there are no differences in shelf life between the treatments. Further work will be required before a recommendation on an economic rate for nitrogen for tomatoes can be made.

In conjunction with trials sponsored by the ADB- Post Harvest project, several variety trials were conducted, and a handful of AVRDC lines were identified as showing promise for production in Cambodia. This includes 'Susan's Joy', and 'Longthick/ Berke's Joy' (CCA4860; PP0337-7562), elite OP lines. Seed on hand at AVRDC will be made available for increases and trial blocks within Cambodia, and additional seed multiplication plantings will be established in the Fall 2006 trials at AVRDC. Trials evaluating post-harvest deterioration of chillies focused on the potential impact of resistance to anthracnose, not only in increasing harvestable crop, but in extending the crops shelf-life with minimal losses. A summary of results can be found in Attachment 2.

Although not replicated, the drip irrigation trials at Kbal Koh were successful and showed some promise for commercial use of the system. The drip system out performed the conventional hand watered plots in both yield and water use efficiency. Total marketable fruit yield from the drip block (12.62 tonnes/ha) was 26% higher than the hand watered block (9.98 tonnes/ha). Average fruit weight from the 1st pick of the drip block was also higher on the drip block at 83.2gms compared to 71.0gms for the hand watered block. Water use efficiency was higher in the drip block at 5.63 tonnes/ML compared to 3.18 tonnes/Ml for the hand watered plots. (See the full report in Attachment 1)

Postharvest training for CARDI, DAALI staff and two participants from Laos on setting-up postharvest trials, quality and shelf life assessment was provided during the Australian teams February visit. This training coincided with harvesting time for the tomato variety trials enabling skills to be implemented immediately with the setting up of the postharvest evaluation of the variety trial and fertiliser trial.

Surveys were conducted in Saang, Kiensvay and Mok Ampil districts in Kandal province, with the tomato grower survey of 50 farmers completed in June, complimenting the earlier ADB survey of market agents, collectors and transporters in late 2005. The chilli survey is currently being drafted, and will be conducted in the next few months. In the ADB project (which we collaborate with closely) survey, 91% of farmers sold tomatoes to collectors, with only 9 % selling directly to wholesalers. 77% of tomatoes handled by the collectors was then on sold to wholesalers, with the remaining product sold to street vendors. 77% of tomatoes sold to wet market vendors arrive in plastic bags, with the remainder packed in cartons, bamboo baskets or styrofoam boxes (8% each). 60% of farmers also reported losses at the farm level due to spoilage.

As part of the Australian component of the project several activities were undertaken including;
a replicated processing tomato variety trial in Barooga, south western NSW
a survey of Cambodian tomato growers in Western Sydney
a consultation meeting with the Cambodian vegetable growers
planning for three 2006/07 cherry tomato grower trials

A drip irrigated replicated processing tomato trial was established at Barooga. The purpose of the trial was to provide practical training for Cambodian scientists in management of on-farm experiments. The Cambodian scientists participated in the harvest of the trial and fruit quality analysis at the Yanco laboratory in late March 2006. While the results were not critical to the project, the data confirmed larger non-replicated machine harvest trial results. H9035 was the best performer in terms of fruit yield at 132 tonnes/ha, while AB2 had the highest total soluble solids content at 5.7% TSS.

Following a meeting with Cambodian growers in February, at which one their priority issues identified was cherry tomato varieties and their postharvest performance, three grower trials in Western Sydney and one glasshouse trial at Gosford has been planned for 2006/07.

In March and April 2006, four scientists (2 from CARDI and 2 from DAALI) visited Yanco Agricultural Institute and Gosford Horticultural institute as part of a project study tour. The scientists received training in a range of field and postharvest trial management methods, data management and analysis, and crop agronomy/ breeding. A tour report was authored by the tour participants.

Objective 1- To map supply chains and identify constraints to improvement of the Cambodian vegetable industry. (Cambodia)

Objective 2- To develop and demonstrate improved production and postharvest strategies that will underpin quality improvement and industry development (Cambodia and Australia)-

Objective 3- To improve R&D capacity in Cambodia in vegetable research, by ensuring maximum sharing of technology and know-how between Australian, AVRDC and Cambodian partners. (Cambodia, Australia and AVRDC).

The project completed its second full year of field and laboratory experiments, conducting cultivar evaluation and post harvest assessment work in chillies and leafy vegetables in addition to the ongoing tomato evaluations. A total of fifteen research station and on-farm replicated and demonstration trials were conducted in Cambodia, and three replicated tomato trials completed in Australia. A series of postharvest experiments and evaluations were also completed at postharvest laboratory now functioning at the Cambodian Agricultural Research and Development Institute (CARDI). On farm commercial testing of the best tomato varieties evaluated in Cambodia so far commenced in the 2006/07 season. Extensive grower and market surveys for tomato and chilli were completed, and these surveys will form a basis for the research and extension components for the second half of the project. Several training activities were also conducted in the 2006/07 period, with training courses involving CARDI, DAALI and the Royal University of Cambodia in biometrics, vegetable pest and disease identification and irrigation management. The project team also delivered a three day irrigation management training course to over 30 technicians working with the NGOs CARE and IDE in Prey Veng Province. In addition, a project study tour to the Mekong Delta and Dalat regions of Southern Vietnam was conducted in late May involving ten Cambodian scientists, one farmer and a representative from both AVRDC World Vegetable Centre and NSW Department of Primary Industries. One of the major outcomes from the pest and disease identification training activities has been the placement, commencing late September 2007, of an Australian Youth Ambassador (AYAD) to work with the Department of Agronomy Plant Protection Team to establish a comprehensive horticultural pests collection. One of the key members of the CARDI project team, NIn Charya also commenced study in a Masters program at Sydney University in August 2007. His major project will focus on the tomato field and postharvest evaluation program as part of this project's Australian component.

Following two years of research conducted mainly on research station sites as part of HORT/2003/045, the project moved into an extension phase, with an increased number of demonstrations and replicated trial plots established on farms. The project also shifted its focus from Kandal province out to other vegetable production regions such as Siem Reap and Kompong Cham.
Selections from the tomato and chilli trials were grown on eleven separate farms across three provinces, Kandal, Siem Reap and Kompong Cham. District and provincial staff assisted Cambodian Agricultural Research and Development Institute (CARDI) and Department of Agronomy and Agricultural Land Improvement (DAALI) team members in managing the sites, and conducting the field days, which were held in February 2008. AVRDC World Vegetable Centre plant breeders also attended the field days. Farmers participated in assessment of the varieties at the CARDI sites in Siem Reap, and this information fed into the evaluation process. Yield and marketability of each variety has been collected and will be reported at the project annual workshop in September 2008. Some of results are presented in this report.
The top three tomato varieties included in the on farm trials were Neang Pich, Neang Tamm and CLN1462A, with these compared with farmers standards at each site. The top yielding tomato variety was Neang Tamm, with marketable yield of 44.5 tonnes per hectare compared with the local variety at 23 tonnes per hectare. The chilli varieties were CCA 321, 9955-15 and PBC 142. These varieties also featured in the mulching and drip irrigation demonstrations.
Screening trials of 32 tomato lines and chilli lines were also conducted at CARDI. There were fourteen varieties of tomato including CLN2777E and CLN2777B showed some commercial potential, and will be advanced to the next stage of testing.
Production trials also moved on farm, with drip irrigation and mulching trials in three locations in Kandal and Kompong Cham. Field days were conducted by the DAALI team at the drip irrigation trial in Kandal, and the mulching / variety trials in Kompong Cham. CARDI also conducted a replicated drip irrigation trial at the CARDI site, while the DAALI team continued their nitrogen rate experiments on chilli at the Dey Eth Research Station.
The establishment of the postharvest laboratory at CARDI is now complete with the installation of the coolroom in April 2008. Assessment of tomato chilli and Chinese kale varieties continued, and results from previous seasons research was presented to farmers at the Siem Reap and Kompong Cham field days. The supply chain surveys for chillies and tomatoes were also completed.
An economic impact case study carried out by a related project, AVRDC managed RETA 6208 with a Kandal farmer demonstrated the benefits flowing from this project. Using improved tomato varieties and production methods (drip irrigation, fertiliser management and trellising) has resulted in an increase in net income for Mr Pho Pich from 3 to 4 million riel in 2005/06 to 6 to 7 million riel income in 2007/08. From one small 10m x 5m demonstration of CLN 1462A with drip irrigation, Mr Pich has harvested over 500 kgs of fruit worth in excess of $100 US, and was still harvesting at the time of the interviews.
A CARDI team member, Nin Charya, commenced a Masters Course at Sydney University under an AusAID scholarship. He completed his major project on tomatoes as part of the Australian component of the project, working with Dr Suzie Newman at the postharvest laboratory at Gosford Horticultural Institute. The project assessed the benefits of using 1-Methylcyclopropene (1-MCP) to extend shelf life of eleven different cultivars of tomatoes.
An adjunct to the vegetable development work occurring at DAALI is the placement of an Australian Youth Ambassador (AYAD) with the DAALI plant protection team to establish a horticultural pest collection. Adelle Dunn arrived in Cambodia in September 2007, and completes her assignment at the end of June 2008. the main focus of the collections will be on pests of vegetables. Apart from field work and preparation of specimens for display, Adelle has also provided training for staff in collecting, storage, preservation and mounting of specimens.
A shortlist of four varieties has emerged from the extensive series of varietal assessments conducted in the Sydney Basin and Gosford. Field yields, postharvest assessments, commercial marketability and taste tests were completed as part of the process. Cherry tomatoes Messina, Felicity, 392-6 and grape tomato TTC8925 were rated the best across a series of field and postharvest assessments over two seasons of autumn and spring trials. A Farmer Field School format, similar to the popular FAO program used in Cambodia, was also tested in during the 2008 tomato season with the Cambodians in Western Sydney.