1999 Missouri Winter Wheat Performance Tests McKendry, Sweets, Wright, Tague, Salzman, Mattas 1999 Test Conditions -------------------- Field conditions during the fall of 1998 were wet at most locations where the performance tests were grown due to excessive fall rainfall. A relatively mild winter resulted in winter survival in excess of 90% in all regions except the southeast where significant unexplained stand reductions were noted. Spring conditions presented adequate rainfall and cool temperatures leading to good tillering and stand development at most locations. In the southeast, soil borne mosaic virus was identified at the Charleston location, (personal communication, Dr. Barb Corwin, Univ. of Missouri Plant Pathologist) which contributed to some differential lodging among varieties, lower yields, and a high experimental error for the test. Consequently, experimental errors for some traits at this location were higher than normal. In the southwest, excessive rainfall during grainfill resulted in significant levels of glume blotch and lodging prior to harvest at Mt. Vernon. Rainfall continued through the harvest period, delaying harvest of the hard wheat test at Mt. Vernon and the soft wheat test at Lamar. Sprouted kernels were observed in the harvested grain of both of these tests with the amount of sprouting being greatest in the hard wheat test. In addition, there was a significant amount of shattering at Lamar due to the delayed harvest. Yield reductions due to shattering were most severe in early varieties in the test. In the northern region, a cool spring with adequate moisture resulted in good stand development and the potential for above average yields. Bacterial streak and black chaff were confirmed (personal communication, Dr. Barb Corwin, Univ. of Missouri Plant Pathologist) in low areas of the test site at Columbia, reducing yields and test weights in susceptible varieties. In addition, both Septoria leaf blotch and leaf rust were observed and rated. Rainfall during the heading period resulted in some development of Fusarium head blight (scab) at Columbia which reduced both yields and test weights in many varieties. Drier conditions at both Novelty and Trenton resulted in these locations being the top yielding locations in the 1999 tests. 1999 Test Results ----------------- The state-wide yield of soft red winter wheats tested in 1999 was 56.5 bushels per acre, up 4 bushels per acre from the 1998 test average of 52.5 bushels per acre. State-wide yields were down 14.5 bushels per acre, however, from the record high yield (71.0 bu/acre) recorded in 1997. Average yields across the seven test locations ranged from 38.1 bushels per acre at Lamar to 66.4 bushels per acre at Trenton. Average regional yields ranged from 44.2 bushels per acre in the southwestern region to 53.9 bushels per acre in the southeastern region and 65.4 bushels per acre in the northern region of the state. 'Pioneer Variety 2568' was again the highest yielding soft red winter wheat tested, averaging 65.0 bushels per acre across the state (Table 6). Six proprietary varieties including: 'Pioneer Variety 25R26' (64.6 bu/acre), 'NK Coker 9663' (63.1 bu/acre), 'Lewis 400' (62.2 bu/acre), 'USG 3209' (62.2 bu/acre), 'AGRIPRO Patton' (61.5 bu/acre), and 'Terra Exp 216' (61.3 bu/acre), did not differ significantly in yield from Pioneer Variety 2568. 'Roane' (61.2 bu/acre), released by the Virginia Agricultural Experiment Station was the only released public variety that did not differ significantly from Pioneer Variety 2568. An experimental line from Georgia, 'GA 89482E7' (61.6 bu/acre), rounded out the top yield group. The eight hard wheat varieties tested (including 'Ernie' as a soft red winter wheat check) averaged 46.6 bushels per acre state-wide (Table 16). Ernie was the top yielding variety in the test, averaging 54.3 bushels per acre across the 3 locations. Released public varieties not significantly different from Ernie included 'Wesley' (50.6 bu/acre), 'Karl 92' (49.6 bu/acre), and '2137' (43.9 bu/acre). The proprietary variety 'Terra HR 217' (46.7 bu/acre), and the Kansas experimental line 'KS89180B2-1-1' (51.9 bu/acre) were also in the top yield group. Regional test weights varied significantly in 1999 due to differential environmental conditions and diseases at test locations. State-wide, the average test weight was 56.9 pounds per bushel (Table 6), not significantly different from the state-wide average (57.0 lb/bu) recorded for 1998. Location averages ranged from a low of 55.2 pounds per bushel at Columbia (Table 7) where disease pressure from scab, bacterial streak, and Septoria leaf blotch along with rainfall during harvest lowered test weights, to a high of 58.6 pounds per bushel at Portageville (Table 11). Among soft red winter wheat varieties tested, 'NK Coker 9474' had the heaviest test weight at 59.3 lb/bu (Table 6). Two public varieties, Roane (59.1 lb/bu) and 'Kaskaskia' (59.0 lb/bu) and two proprietary varieties, 'MFA Enterprise' (58.9 lb/bu) and 'NK Coker 9704', (58.5 lb/bu) did not differ significantly from NK Coker 9474. NK Coker 9474 has been the variety with the heaviest test weight in 3 of the past 4 years. Across the three locations of the hard wheat test, Karl 92 had the heaviest test weight at 56.7 lb/bu. Not significantly different from Karl 92 were 2137 (55.1 lb/bu), Wesley (54.7 lb/bu), Terra HR 217 (54.4 lb/bu) and the soft wheat check, Ernie (54.6 lb/bu). The Nebraska experimental line 'NE 93496' (55.8) was also in the top test weight group, ranking second behind Karl 92.