000			02937nam a22003977a 4500
001			G66304
003			MX-TxCIM
005			20211006075459.0
008			121211s ||||f| 0 p|p||0|| |
020			_a970-648-001-3
040			_aMX-TxCIM
072		0	_aF07
072		0	_aH20
082	0	4	_a633.1194 _bDUV
100	1		_aKrupinsky, J.M. _uHelminthosporium Blights of Wheat: Spot Blotch and Tan Spot. Proceedings of an International Workshop; El Batan, Texcoco (Mexico); 9 - 14 Feb 1997
110	2		_aCentro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), Mexico DF (Mexico)
245	0	0	_aLeaf spot diseases of wheat in a conservation tillage study
260			_aMexico, DF (Mexico) _bCIMMYT|UCL|BADC : _c1998
340			_aPrinted
520			_aA conservation tillage cropping systems project was initiated 12 years ago to study the influence of crop rotation, tillage practice, fertility level, and crop cultivar on the severity of leaf spot diseases. The experiment included the following experimental variables in all combinations with three replicates: 1) two cropping rotations (spring wheat-fallow and spring wheat- winter wheat-sunflowers); 2) three tillage treatments (conventional till, minimum till, and zero till); 3) three nitrogen (N)fertilizer rates; and 4) two cultivars of each crop grown. Pyrenophora tritici-repentis and Stagonospora nodorum (syn. Septoria nodorum) were the main causal agents of a leaf spot disease complex. Higher levels of necrosis and chlorosis were associated with the no additional N (crop-fallow) and the low N (continuous cropping) treatments compared to higher N levels. When significant differences were evident among tillage treatments, in general higher levels of necrosis and chlorosis were associated with wheat leaves from zero till plots than those from minimum or conventional till plots. The winter wheat cultivar Roughrider had higher levels of necrosis and chlorosis compared to Norstar; however, the differences between the spring wheat cultivars Stoa and Butte 86 were not consistent. With some disease ratings, the effect of tillage on leaf spot diseases varied depending on N level. With the no additional N and low N treatments, leaf spot severity was higher under zero tillage than conventional tillage, but at the higher N treatments the differences in leaf spot severity among tillage treatments was greatly reduced or eliminated.
546			_aEnglish
591			_a9806|AGRIS 9802
593			_aJose Juan Caballero
595			_aCPC
650	1	7	_aCropping systems _gAGROVOC _2 _91068
650	1	7	_aPlant diseases _gAGROVOC _2 _91206
650	1	0	_aSpots
650	1	0	_aZero tillage
653	0		_aCIMMYT
650	1	7	_aTriticum _gAGROVOC _2 _91295
650	1	0	_91056 _aConservation tillage _gAGROVOC
700	1		_aBlack, A.L, _ecoaut.
700	1		_aDuveiller, E.|Dubin, H.J.|Reeves, J.|McNab, A. _eeds.
700	1		_aHalvorson, A.D., _ecoaut.
942			_cPRO
999			_c3851 _d3851