000			03686nab a22004217a 4500
001			G448453
003			MX-TxCIM
005			20231002172253.0
008			210810s2002 xxu|||p|op||| 00| 0 eng d
022			_a1435-0653 (Online)
024	8		_ahttps://doi.org/10.2135/cropsci2002.1882
040			_aMX-TxCIM
041			_aeng
072		0	_aF01
072		0	_aF30
090			_aCIS-3496
100	1		_9832 _aPixley, K.V. _gGenetic Resources Program _8INT1617
245	1	0	_aStability of grain yield, endosperm modification, and protein quality of hybrid and open-pollinated quality protein maize (QPM) cultivars
260			_aUSA : _bCSSA : _bWiley, _c2002.
340			_aPrinted|Computer File
500			_aPeer review
500			_aPeer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=0011-183X
520			_aQuality protein maize (Zea mays L.) (QPM) can help alleviate human malnutrition and reduce costs of animal feed because it contains the opaque-2 mutation, which results in increased lysine and tryptophan concentrations and a higher biological value as a food than normal maize. To be commercially successful, however, QPM cultivars must be agronomically competitive with normal-endosperm alternatives while consistently achieving expected protein quality and endosperm modification (i.e., translucent or near-normal phenotype) standards. To assess stability of grain yield, protein content and quality, and endosperm modification of QPM cultivars, we evaluated 18 single-cross, 18 three-way, and 18 double-cross hybrids, and eight open-pollinated cultivars (OPCs) grown at 13 tropical locations on four continents. Hybrids averaged 13% higher grain yield than OPCs (5.97 and 5.17 Mg ha−1), whereas protein concentration in grain was 2% greater for the OPC relative to hybrid cultivars (94.6 and 92.4 g kg−1). Endosperm modification score and tryptophan concentration in protein were similar for all cultivar types. Genotype × environment interactions and sums of squares for deviations from linear regression S2d for grain yield and protein concentration in grain were largest (indicating least stability) for single-cross hybrids, followed by three-way, double-cross, and open-pollinated cultivars (OPCs), successively. The reverse trend was observed for endosperm modification score, suggesting that more homogeneous cultivars had greater stability for this trait. Additive main effects and multiplicative interactions (AMMI) analysis indicated that genotype × environment interaction effects for grain yield and endosperm modification score were different for hybrids than OPCs; certain environments favored either hybrids or OPCs. In conclusion (i) protein quality and endosperm modification score were always within expected values for QPM and (ii) tryptophan concentration in protein was the most stable trait, followed by protein concentration in grain, then endosperm modification score and finally grain yield.
536			_aGenetic Resources Program
546			_aText in English
591			_a0211|Crop Science Society of America (CSSA)|AL-Wheat Program|R01JOURN
594			_aINT1617
650		7	_91173 _aMaize _2AGROVOC
650		7	_91224 _aProteins _2AGROVOC
650		7	_91313 _aYields _2AGROVOC
650		7	_96574 _aOpen pollination _2AGROVOC
650		7	_91151 _aHybrids _2AGROVOC
650		7	_91303 _aVarieties _2AGROVOC
700	1		_aBjarnason, M. _97750
773	0		_tCrop Science _n631653 _gv. 42, no. 6, p. 1882-1890 _dUSA : CSSA : Wiley, 2002. _wG444244 _x1435-0653
856	4		_yAccess only for CIMMYT Staff _uhttps://hdl.handle.net/20.500.12665/1004
942			_cJA _2ddc _n0
999			_c22514 _d22514