WORKSHOP RECOMMENDATIONS

Participants in the International Rice Research Workshop grouped specific recommendations for future cooperation on rice research problems of mutual interest under five major areas:

INTERNATIONAL RICE TESTING PROGRAM

The Chinese participants requested the following nurseries for testing in 7 provinces during the 1980 rice-growing season:

INNOVATIVE BREEDING METHODOLOGIES

1. Hybrid riceThe participants agreed to initiate collaborative research on hybrid rice with the following objectives:

Compare different cytoplasmic male sterility systems available now and search for better sources;

Develop cytoplasmic male-sterile lines with disease and insect resistance and adaptability to tropical and subtropical conditions using the presently available cytosterile sources;

Study the nature of hybrid vigor and identify lines with better general and specific combining abilities;

Identify germplasm with large stigmas and longer flower-opening times, and transfer those traits to male-sterile lines;

Study the ratooning potential of F1 hybrids; Study the inheritance of fertility restoration; Investigate the ways and means of perpetuating the F1 hybrids such as by converting them to

apomictics. Study the techniques of hybrid seed production. Scientists from the People's Republic of China (PROC), India, and IRRI will initially participate in

the project. Representatives of Sri Lanka, Bangladesh, Thailand, and Indonesia will discuss the project with

their colleagues and possibly join after they develop more manpower.

2. Tissue culture

It was agreed that collaborative work on tissue culture will be initiated with major emphasis on standardizing the culture media. Seeds of about 30 crosses should be sent from IRRI to Mr. Zhang Zen-Hua by March 1980. He will select about 15 combinations, process them through anther culture techniques, and send seeds of 400-600 fixed lines back to IRRI for evaluation under specific environmental conditions and stresses.

Crosses of the following combinations may be considered: Indica/japonica Indica/indica Japonica/japonica Indica/glaberrima

Participants from PROC, Bangladesh, Sri Lanka, and IRRI expressed interest in joining the collaborative project.

Representatives of Indonesia and India will discuss the project with their colleagues.

3. Exchange of early-generation materials for early maturityScientists agreed that the exchange of early-generation materials of crosses for early maturity would be of mutual benefit. IRRI will initially send 11 sets of about 300 early generation breeding lines (10 g seed of each line) to China.

The seed will be distributed to the agricultural academies of Guangdong, Guangxi, Zhejiang, Hunan, and Jiangsu provinces and to the Chinese Academy of Agricultural Sciences (CAAS), Beijing. The materials will be evaluated in the two cropping seasons of those five provinces. A single plot consisting of about 4 rows, each 5 m long, will be grown. Observations on the growth duration and other traits will be recorded and selections for local trials will be made. The Chinese academies will similarly supply seed of their early-generation materials to IRRI. Scientists in Sri Lanka, Bangladesh, India, and Indonesia will also exchange early-generation materials.

RICE DISEASES

1. Virus diseases

Because the major virus diseases in China differ from those in South and Southeast Asia, the cooperative work with China will be limited to an exchange of literature and information on virus diseases.

2. Bacterial blightThe objectives of the existing international collaborative project on pathogenic strains of Xanthomonas oryzae and host resistance in rice are:• Establishment of a standard set of rice differentials in an isogenic background for a monogenic basis for strainal studies, • Study of the virulence and variability of the bacteria in Asia, and • Identification of diverse genes for resistance and incorporating them into improved germplasm.

Chinese scientists expressed their interest in participating in the project in four provincial academies: Guangdong, Zhejiang, Jiangsu, and Guangxi. Scientists in Bangladesh, India, Indonesia, and Thailand will continue to cooperate.

3. Rice blastThe group suggested the need for a collaborative project to study differentials for races of Pyricularia oryzae with the following objectives:

• Establishment of an improved international set of differentials to study the races of the fungus. • Monitoring the distribution of races of Pyricularia oryzae and varietal resistance of commercial varieties.

It was suggested that the project be discussed further during the International Rice Research Conference at IRRI in April 1980.

RICE INSECTS

1. BPH collaborative projectThe PROC scientists would like to carry on the collaborative project on the brown planthopper in the following locations:

Scientists from Bangladesh, India, Indonesia, Sri Lanka and Thailand will continue to participate.

2. Gall midge biotype collaborative project

Chinese scientists at the Guangdong Academy of Agricultural Sciences (AAS) will conduct the trial.

3. Special screening setsThe Chinese scientists of Jiangsu AAS will conduct screening trials to identify:

• varieties resistant to all known BPH biotypes, • thrips-resistant varieties, and • leaffolder-resistant varieties.

4. Biological control of rice insect pests

To further the study of parasites and predators of stern borers, leaffolders, and planthoppers, there will be an exchange of preserved parasite and predator specimens to identify natural enemies that are native to certain countries and lacking in others. Natural field parasitism at IRRI and in China will be compared.

5. Insecticides

Literature on insecticide evaluation studies, application methods, etc. will be exchanged between IRRI and China.

CAAS-IRRI COLLABORATION ON GERMPLASM COLLECTION AND MAINTENANCE

The objectives of this project are:• Expansion of the exchange of germplasm among institutions so that Chinese scientists in various provinces can supply fresh seed to IRRI every year as the seeds are rejuvenated. • The inventory of Chinese accessions and comparison with those in the IRRI collections. • CAAS and IRRI cooperation in field collection, characterization, seed storage, and data systems. • Development of a procedure to inform both national and provincial agencies concerned on seed exchange activities.

• Seed increase at IRRI and as has been done in other instances, making seeds available to rice researchers of other countries upon request. Similarly, Chinese researchers can freely obtain from IRRI seeds of the deposited accessions to replace those that may have been lost.

Since the development of the exchanges of germplasm is very important for raising efficiency of rice breeding, the Crop Germplasm Institute at CAAS will take charge of coordinating the work in China and the cooperative work with IRRI.

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Anonymous. 1980. Anonymous. 1980. Workshop recommendations and glossary. Pages 293-307. In: Thomas R. Hargrove (editor). Rice improvement in China and other Asian countries. International Rice Research Institute and Chinese Academy of Agricultural Sciences, 307 p.

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Citation: Anonymous. 1980. Workshop recommendations and glossary. Pages 293-307. In: Thomas R. Hargrove (editor). Rice improvement in China and other Asian countries. International Rice Research Institute and Chinese Academy of Agricultural Sciences, 307 p.

Keywords: Oryza sativa, rice breeding, wide crosses, plant maturity, plant disease, pathogen strain, insect pest, host plant resistance, brown planthopper Nilaparvata lugens, biotype, leaffolder Cnaphalocrocis medinalis, thrips Stenchaetothrips biformis, natural enemies, parasitoid, predator, germplasm exchange