Annual Research Report 1999: lowland tropical - HQ maize subprogram
Inter-population improvement using reciprocal recurrent selection (RRS) in the tropical lowland, has been enhanced focussing on selection against biotic and abiotic stresses, with the support of the Entomology, Pathology and Physiology units. In the tropical subprogram one cycle of S2 recurrent selection will be completed in two years. The formation of new experimental varieties will be speeded-up. Two new sets of populations heterotic to each other (2 white and 2 yellow) are being formed. 22 new synthetic, OPVs were formed, advanced to F2 and tested in international trials; new synthetic cultivars are more uniform and more appealing to farmers. Yield in the synthetics is similar to the normal experimental varieties. Six synthetics resistant to insects (FAW), to drought and low nitrogen, were developed, advanced to F2 and will be tested in international trials in the year 2000. New com stunt disease (CSD) resistant synthetics: P73 NICI, P73 NIC2, P73 NISAl, yielded up to 7 .2 tons per hectare, under non infested conditions with a minimal decrease in yield of 7.1, 5.3 and 7.9% respectively under heavy CSD infection. The single cross hybrid CML24 7 x CML254 suffered a yield reduction of 4 7%. All 3 synthetics were resistant to B. maydis and P. polisora. 10 lines with good GCA adapted to tropical lowland, were identified and proposed for immediate release; some lines are resistant to insects, drought, low-N, foliar diseases and ear rot. 6 new white and yellow tropical elite inbred lines 'testers' were identified and are in current use. The new testers will eventually replace the earlier tropical testers. More than 1500 tropical new hybrid combinations with adaptation to tropical lowland, in Latin America and Asia were tested in several locations in stressed and non-stressed environments in 1999. Superior hybrids outyielded the best seed industry check up to 30% and, possessed superior agronomic traits. 8 QPM hybrids with tropical adaptation were released by INIFAP. The ceremony was attended by the Mexican Secretary of Agriculture, Prof. Timothy Reeves and Dr. Norman Borlaug. The best hybrids yield 10% better than the best seed industry checks and contain 60 to 100% more triptophan and lysine. It is planned to plant 500,000 ha of QPM in Mexico soon. In collaboration with RS and PRM, we released QPM hybrid HQ-61 in El Salvador. The ceremony was attended by the Vice President, Minister of Agriculture, Minister of Foreign Relations, Vice President of Nicaragua, public, private and seed industry representatives, Dr. Norman Borlaug and Dr. Shivaji Pandey and other CIMMYT Staff. The government of El Salvador presented a plan to cover 70% of the area planted with QPM maize in four years. The plan for seed production in 2000 is to produce 800 tons of seed to enable the planting of 40,000 hectares by 2001. In Guatemala we released HB-PROCTICTA with similar results as in El Salvador. In 1999 we tested 23 tropical QPM hybrids at 28 locations in Asia and Latin America. Best QPM hybrids outyielded the best seed industry checks by region and countries. Research in swine feeding conducted in September 1999 and January 2000 in El Salvador and in Guatemala is very promising and very similar to the earlier studies conducted in the 1970's and in 1994. In both cases, pigs fed with QPM gained 600 g/day while the ones fed with normal maize gained only 300 g/day. In collaboration with R5 and SAMP in Venezuela, FONAIAP tested tropical and CIMMYT Cali hybrids in seven locations in the State of Portuguesa. Results across several locations indicate that the CIMMYT hybrid CL02198 x CML274 yielded 10.5 t/ha and the best check 8.5 t/ha, while the Pioneer hybrid yielded 6.5 t/ha. QPM results in Venezuela are also very exciting. The hybrid (CML142 x CML15) x CMLl 76 topped the trial at Guarico with 6.5 t/ha, 15% more than the seed industry check. The best selected hybrid will be tested in strip tests in 2000. In Peru tropical yellow hybrids yielded up to 14 t/ha up to two tons more than the best checks. Superior hybrids identified will be evaluated in strip tests in 2000. In Colombia yellow QPM hybrid CML161 x CML165 and white endosperm (CML144 x CML159) QPM hybrids outyielded the best seed industry check G-5324 and Cargill C-343 respectively, by more than 1 t/ha with double lysine and triptophan content. QPM hybrids are being proposed for release in 2001. We have shipped 12 trials including QPM hybrids to Ecuador, Paraguay and Bolivia for the purpose of testing in multi-location trials in 2000. In Thailand G2 in collaboration with R2 and ARMP, tested six different trials at the Suwan Farm site. In each trial at least two entries outyielded the best seed industry check by 1-2 t/ha. Even allowing for heavy residual herbicide damage, CIMMYT tropical hybrids demonstrated superiority for yield potential and resistance to ear rot and P. polysora. G2 in collaboration with F4 identified 8 new white endosperm elite QPMs with good GCA for immediate release. The lines were identified from the results of advanced test crosses conducted in 10 locations during 1999/A and B cycles. New F2 pedigree breeding population using elite QPM lines and normal white and yellow elite coded inbred lines have been developed and pedigree selection will be continued in 2000. A very important alliance emerged between the CIMMYT Maize Program and Grupo Maseca-Central America Andean Region. Grupo Maseca visited the CIMMYT Maize Program in early February and expressed their desire to join forces with CIMMYT in promoting QPM hybrid maize in Central America (Guatemala, El Salvador, Honduras, Nicaragua and Costa Rica) and South America (Colombia, Venezuela) through promoting and recommending our hybrids released by National Programs in "El Club del Maiz de Maseca", using the most advanced agronomic technologies and the best QPM hybrids available. We had a meeting with the Directors also in Guatemala during the release of HBProticta. They are prepared to purchase the hybrid seed from small private companies in each country and distribute to farmers, eliminating the intermediaries. Our collaboration with SG2000 was enhanced during the meeting held at CIMMYT in November 1999. We presented a progress report on QPM development and transfer that was regarded as impressive by most of the members. An enhanced collaboration emerged from that meeting with the promise of more interaction for the promotion of our products to farmers. 1999 was very positive scenario for the relationship between CIMMYT's Maize Program and NARS in Mexico. A true partnership between INIFAP and CIMMYT was also established, with INIF AP providing 200 kg. of basic seed that was sent to Guatemala, for hybrid seed production. There also has been mutual public recognition of QPM development. Fundación Mexicana para la lnvestigaci6n Agricola also recognized our effort by granting 100,000 to CIMMYT to continue research on QPM. CIMMYT and Texas A&M have initiated a partnership by identifying areas of common interest and developing a joint proposal with emphasis on tolerance to drought and heat, aflatoxins and breeding for QPM hybrid development. In association with QPM germplasm improvement, assistance from the University of Arizona has allowed CIMMYT to produce antibodies that react with the maize elongation factor 1 a, that is highly correlated to lysine content of the endosperm. Antibodies were produced and provided to NARs with germplasm improvement programs for QPM maize. Serological tests will help in the selection process needed to develop QPM maize, using the ELISA technique.
| Main Authors: | , , , , , , , |
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| Format: | Annual Report biblioteca |
| Language: | English |
| Published: |
CIMMYT
1999
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| Subjects: | AGRICULTURAL SCIENCES AND BIOTECHNOLOGY, GERMPLASM, MAIZE, QUALITY, RESEARCH PROJECTS, VARIETIES, ZEA MAYS, |
| Online Access: | http://hdl.handle.net/10883/3673 |
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