000			03528nam a22004337a 4500
001			G70466
003			MX-TxCIM
005			20240919021053.0
008			121211s ||||f| 0 p|p||0|| |
020			_a92-9146-058-3
040			_aMX-TxCIM
072		0	_aF30
072		0	_aH20
090			_aLook under series title
100	1		_aBoshoff, W.H.P. _uRegional Wheat Workshop for Eastern, Central and Southern Africa, 10; University of Stellenbosch, South Africa; 14-18 Sep 1998
110	2		_aCentro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), Addis Ababa (Ethiopia)
245	0	0	_aStripe rust: _b a new threat to wheat production in South Africa
260			_aAddis Ababa (Ethiopia) _bCIMMYT : _c1999
340			_aPrinted
500			_aAbstract only
520			_aStripe (yellow) rust, caused by Puccinia striiformis Westend. f. sp. tritici Eriks., is one of the most important diseases of wheat (Triticum aestivum L.). Yield losses as high as 84% have been recorded under severe epidemic conditions. During August 1996, stripe rust was observed for the first time on bread wheat in the Western Cape, South Africa. Ensuing surveys during 1996 indicated that stripe rust spread to most of the wheat producing areas in the winter rainfall region of the Western, Southern and Eastern Cape and to irrigated wheat in the summer rainfall area south of Kimberley. In 1997 the disease was observed early in the season in the Western Free State from where it spread to the rest of the province, KwaZulu-Natal, Gauteng, the North West and Northern province. In the Southern Cape and Eastern Free State the pathogen over-summered successfully on volunteer wheat plants. Infected grass species, serving as accessory stripe rust hosts, were also observed in the Western Cape and Eastern Free State. The rapid dispersal of stripe rust during the 1996 and 1997 wheat seasons, the ability of P. striiformis to over-summer in both the winter and summer rainfall regions, susceptibility of several wheat cultivars, favourable climatic conditions in many wheat growing areas in South Africa, and additional costs of fungicide application, qualify stripe rust as a damaging disease with strong impact in local wheat production. A low percentage of both winter and spring cultivars expressed complete resistance, presumably controlled by race-specific genes, towards pathotype 6E 16 of P. striiformis f. sp. tritici. The high mutation potential of the stripe rust pathogen could drastically alter the current resistance status in these cultivars. Future breeding efforts should be directed towards strategies to obtain effective and durable resistance against stripe rust. The release of cultivars containing only race-specific resistance genes should be strongly discouraged. Selection of resistance sources for application in breeding programs should focus almost entirely on genotypes with known durability.
546			_aEnglish
591			_a0007|AGRIS 0101|AL-Wheat Program
593			_aJose Juan Caballero
595			_aCPC
650	1	7	_aBreeding methods _gAGROVOC _2 _91030
650	1	0	_aDisease control
650	1	0	_aFood production _91116
650	1	7	_aPlant diseases _gAGROVOC _2 _91206
650	1	0	_91842 _aPuccinia striiformis _gAGROVOC
650	1	7	_aRusts _gAGROVOC _2 _91251
650	1	0	_aSouth Africa
653	0		_aCIMMYT
650	1	0	_91296 _aTriticum aestivum _gAGROVOC
650	1	7	_aPlant breeding _gAGROVOC _2 _91203
700	1		_aVan Niekerk, B.D., _ecoaut.
700	1		_9654 _aPretorius, Z.A.
942			_cPRO
999			_c4520 _d4520