Cucurbits claim the crown

Outstanding results from global bitter gourd and pumpkin breeding programs

AVRDC showcased its treasure trove of bitter gourd breeding lines during Bitter Gourd Open Field Days from 9-23 August 2015 at AVRDC East and Southeast Asia’s Research and Training Station, Kasetsart University, Kamphaeng Saen, Thailand. Seventeen cucurbit breeders and plant pathologists from 11 leading seed companies in Asia took to the plots to examine 400 advanced breeding lines and select the best for their purposes.

These lines belong to different market segments popular with growers and consumers in different regions of Asia. Lines have been bred for resistance to diseases such as powdery mildew, downy mildew, and Cercospora leaf spot, as well as enhanced fruit quality (soft seed during harvest at marketable maturity stage; proper fruit color development; improved yield; extended shelf life). Some lines were rated field-resistant to viruses by the visitors.

Visitors focused on vine stem vigor, profuse branching patterns, disease resistant traits, fruit quality and yield. Seed company breeders also showed keen interest in AVRDC’s recurrent selection program in the field, which aims to breed genetically broad bitter gourd lines possessing multiple disease resistance and improved fruit quality and yield.

Aerial view of the 400 bitter gourd lines in the demonstration trial.

Aerial view of the 400 bitter gourd lines in the demonstration trial.

Breeders from the seed sector discussed with Cucurbit Breeder Narinder Dhillon how to exploit these lines to develop elite hybrids best suited to the needs of growers and consumers. Narinder is building a cucurbit support group among seed companies so that breeders can benefit more from the Center’s current cucurbit breeding research. “The energy, enthusiasm, dedication, and competitive breeding skills of my highly motivated cucurbit team supervised by Research Assistant Supannika Sanguansil has brought this huge breeding success,” said Narinder.

Fenton Beed, East and Southeast Asia Regional Director, agrees. “The cucurbit breeding program is the jewel in the AVRDC East and Southeast Asia crown,” Fen said with pride.

In 2010 the breeding program was transferred from the Center’s headquarters in Taiwan to Thailand, where field conditions are more favorable to cucurbit production. The presence of numerous fungal and viral cucurbit diseases allows breeders to select the best lines demonstrating resistance in the field. In the hot but relatively calm climate (no typhoons), breeders can grow three crops per year, and thus produce more lines to evaluate for suitability. During the dry season of April-May, when the day temperature fluctuates between 36-40 °C, breeders can select cucurbits for the ability to set fruit in high temperatures.

Cucurbits for Thailand’s highland communities

The Highland Research and Development Institute (HRDI) is a public organization in Thailand that works closely with the Royal Project Foundation to encourage the use of technologies and innovations by highland communities in the country. In March 2015, an HRDI delegation led by Kesaraporn Sreechun (Ket), Head of the Research Program at HRDI Chiang Mai, visited AVRDC East and Southeast Asia’s Research and Training Station at Kasetsart University, Kamphaeng Saen, Thailand. The visitors saw pumpkin and bitter gourd breeding trials, traits of AVRDC cucurbit lines, the demonstration garden and integrated pest management laboratory. HRDI showed immense interest in the pumpkin and bitter gourd lines, which they planned to evaluate in local farmers’ fields.

AVRDC Cucurbit Breeder Narinder Dhillon, Research Assistants Supannika Sanguansil (Breeding) and Sopana Yule (Entomology), and Regional Training Office Somchit Pruangwitayakun visited HRDI stations in Chiang Mai and Kanchanaburi on 28-29 July and 21 August 2015, respectively to select suitable sites for the cucurbit trials. They also set out to evaluate consumer preference for these two crops by visiting local markets and meeting with growers.

Staff from AVRDC and HRDI discuss trial site selection in Chiang Mai.

Staff from AVRDC and HRDI discuss trial site selection in Chiang Mai.

At both sites, Narinder and Supannika gave presentations on the horticultural traits, including disease resistance, of the Center’s bitter gourd and pumpkin lines. They also discussed consumer-preferred traits, seed availability, planting season, method of planting, and the sites selected for first-year trials. Based on these participatory trials, HRDI will select one or two AVRDC lines for multilocation participatory trials to promote adoption among highland communities.

The aim is to motivate people in the highlands of Huay Pao (Chiang Mai) and Huay Kayaeng (Kanchanaburi) provinces to grow nutritious vegetables such as bitter gourd and pumpkin for their consumption first, and then sell any extra produce in the local market to augment their income. Somchit outlined the strategy of establishing home gardens in these regions and the components of the garden, illustrating with examples of successful garden projects. She explained how AVRDC could extend its expertise in this area to make HRDI’s home garden project a success.

Sopana identified the role of integrated pest management in HRDI’s self-sufficiency project and emphasized the knowledge and value AVRDC’s IPM group can bring in this area. “We see an excellent opportunity for AVRDC and HRDI to cooperate on the adoption of AVRDC cucurbit lines by our local highland communities,” remarked Ket during AVRDC’s visit to Chiang Mai. “This will support our current food security research program.”

Story and photos: Narinder Dhillon

A breeder from VNR Seeds observes traits of bitter gourd lines.

A breeder from VNR Seeds observes traits of bitter gourd lines.

The "Cucurbit Crew" at AVRDC East and Southeast Asia.

The “Cucurbit Crew” at AVRDC East and Southeast Asia.

Your solid recurrent selection program, well-planned crossing blocks and variety evaluation blocks were well worth seeing. There is an enormous good effort here on breeding multiple disease resistant bitter gourd lines. We feel this program will be very useful to small- and medium-sized companies like us to reach farmers by using AVRDC lines.Gopalkrishna Hegde, Director Research, Noble Seeds, India
Thank you for showing your amazing bitter gourd breeding material. Your team has made available to us a collection of different valuable traits in bitter gourd for our breeding program, especially for powdery mildew and virus resistance.S. Thippeswamy, Cucurbit Breeder, Bayer Crop Science Vegetable Seeds, India