000			03153nam a22004937a 4500
001			G80728
003			MX-TxCIM
005			20211006084755.0
008			121211s ||||f| 0 p|p||0|| |
020			_a970-648-120-6
040			_aMX-TxCIM
072		0	_aE16
072		0	_aP35
082	0	4	_a338.16 _bFRI
100	1		_aKamara, A.Y. _uIntegrated Approaches to Higher Maize Productivity in the New Millennium
110	0		_aCentro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT) Kenya
111	2		_a7. Proceedings of the Eastern and Southern Africa Regional Maize Conference _cNairobi (Kenya) _d5-11 Feb 2002
245	0	0	_aVertical root-pulling resistance in maize is related to nitrogen uptake and yield
260			_aNairobi (Kenya) _bKARI|CIMMYT : _c2002
300			_ap. 228-232
340			_aPrinted
520			_aPoor soil fertility and recurrent drought are major constraints to maize production in the West African savanna. The development of maize cultivars with superior rooting system to absorb nitrogen and water efficiently from the soil is desirable. However. direct measurement of root characteristics for rapid selection of maize lines having tolerance to the two stresses is difficult. Vertical root-pulling strength. which has been shown to relate well to the rooting characteristics of the maize plant could be an alternative trait that can be used in improving the efficiency of selection of maize lines for tolerance to low-N stress and drought. This trait has effectively been used to select maize lines for resistance to corn root rot and lodging. Field evaluations were conducted during 2000 and 2001 to determine the root-pulling strength. yield. N-uptake and N-use of maize S1 lines derived from selected full-sib families from a Low-N tolerant population. There were significant differences in vertical root-pulling strength. N-uptake. N-use efficiency and yield among the maize breeding lines. Root- pulling strength positively correlated with N-uptake and maize yield. However. some S1 lines gave a higher grain yield despite low root-pulling strength. Other factors such as high numbers of cars per plant and high N-utilization efficiency were responsible for these yield increases. Because of the magnitude of the differences between S1 lines in root-pulling strength and the positive correlation of this trait with N-uptake. it can be used in selecting lines for variations in the rooting system and for high N uptake efficiency.
546			_aEnglish
591			_a0410|AGRIS 0401|AL-Maize Program
593			_aJuan Carlos Mendieta
595			_aCPC
650	1	0	_aAfrica
650	1	7	_aCultivation _gAGROVOC _2 _91071
650	1	0	_aDrought resistance
650	1	7	_aMaize _gAGROVOC _2 _91173
650	1	0	_aNitrofen
650	1	0	_aSeed production _91253
650	1	0	_aWater
650	1	0	_aYield factors
653	0		_aCIMMYT
653	0		_aKARI
650	1	0	_91314 _aZea mays _gAGROVOC
650	1	0	_91952 _aSoil fertility _gAGROVOC
700	1		_aAjala, S.O., _ecoaut.
700	1		_aFriesen, D.K.|Palmer, A.F.E. _eeds.
700	1		_aKling, J.G., _ecoaut.
700	1		_91818 _aMenkir, A.
942			_cBK
999			_c7376 _d7376