000 03169nam a22004577a 4500
001 G73047
003 MX-TxCIM
005 20240919020957.0
008 121211s ||||f| 0 p|p||0|| |
020 _a81-7663-888-9
040 _aMX-TxCIM
072 0 _aF01
072 0 _aF30
090 _aCIS-3266
100 1 _aSingh, R.P.
_gGlobal Wheat Program
_8INT0610
_9825
245 0 0 _aGenetics of slow disease development:
_b The Puccinia and Triticum system
260 _aJalandhar (India)
_bKalyani publishers :
_c2001
300 _ap. 246-255
340 _aPrinted
520 _aLeaf (or brown) rust caused by Puccinia triticina and yellow (or stripe) rust causcd by P. striiformis tritici are the two most important production constraints in several wheat growing regions of the world. Growing resistant cultivars has no cost to farmers and is the most environmentally friendly control measure. Resistance to rust diseases that is based on racc-specific genes is usually effective for about five years. An alternative approach to achieve resistance durability is to breed cultivars that have race-nonspecific type of resistance, Our studies show that durable resistance can be achicved by combining genes that confer slow rusting. Named slow rusting genes. viz. Lr34 and lr46 for leaf rust and Yr18 for yellow rust resistance. are associated with an increased latent period and reduced infection frequency and uredial size (or length of stripe in yellow rust). This indicates that the components of slow rusting are under pleiotropic genetic control: hence a single mechanism at the cellular level. formation of cell wall appositions. must be affecting all components, A single slow rusting gene confers only a small to moderate reduction in disease progress. but gene combinations result in additive effects with improved resistance, Between 3 to 4 genes for leaf rust and 4 to 5 for yellow rust must be combined to reduce disease progress to a level that only trace severity is seen at maturity under high disease pressure. Such resistance has been developed in CIMMYT wheats and is considered to be durable and race-nonspecific, Cultivars with slow rusting resistance must be released and promoted to permit long term rust control and enable breeders to emphasize breeding for higher yield potential and other desired traits. Diagnostic molecular markers for slow rusting genes are not yet available. so high priority must be given to obtaining them rather than identifying markers for race-specific genes.
536 _aGlobal Wheat Program
546 _aEnglish
591 _a0111|R99-00PROCE|AL-Wheat Program|AL-ABC Program|3
593 _aMaria del Carmen Nava
594 _aINT0610
595 _aCSC
650 1 7 _aCultivation
_gAGROVOC
_2
_91071
650 1 0 _aDiseases
650 1 0 _aGenes
650 1 0 _aGenetic control
_91694
650 1 0 _aGrowth
650 1 0 _aMexico
650 1 0 _aPuccinia
650 1 7 _aRusts
_gAGROVOC
_2
_91251
650 1 0 _aWheat
653 0 _aCIMMYT
700 1 _aNagarajan, S|Singh, D.P.
_eeds.
700 1 _aHuerta-Espino, J.
_gGlobal Wheat Program
_8CHUE01
_9397
700 1 _9661
_aRajaram, S.
_ecoaut.
942 _cPRO
999 _c4882
_d4882