Dry Edible Bean Desiccants
April 13, 2004
In 2002 and 2003, field research was conducted at three locations to evaluate desiccation of navy and pinto beans. In 2002, twelve registered and experimental herbicides were applied at recommended rates: Diquat, Gramoxone Extra (paraquat), Glyphosate, Rely (glufosinate), Desicate II (endothall), Aim (carfentrazone), Cobra (lactofen), Valor (flumioxazin), ET-751, caprylic acid, and S-3100. From the results of 2002 field research studies, seven of the most effective compounds were used in 2003 trials. In 2003, Diquat, Gramoxone Extra, Glyphosate, Rely, Desicate II, Cobra, and Valor were applied at recommended rates with most effective adjuvants if used. Navy bean sites were located at Hatton and Prosper, ND. At Prosper, only Desicate II and Valor gave greater than 80% leaf desiccation 7 days after application. Diquat, Gramoxone Extra, Glyphosate, and Rely caused less than 80% leaf desiccation. Leaf desiccation in the untreated check was 64%. At Hatton, leaf desiccation was similar to Prosper for all treatments, although Diquat, Rely and Cobra were slightly above 80%. Leaf desiccation in the untreated check was 49%. Diquat, Desicate II, and Valor gave greater than 73% vine desiccation in Prosper 7 days after application. Vine desiccation in the untreated check was 15%. In Hatton, Rely, Desicate II, Cobra, and Valor gave better than 76% vine desiccation compared to the untreated check of 19%. Seed moisture was taken 7 days after application. At Prosper, seed moisture ranged from 11 to 16% in treated plots and 22% in the untreated check. Seed moisture at Hatton ranged from 12 to 34% moisture in treated plots and 13% in the untreated check due primarily to accelerated dry down from bacterial blight. However, endothall treatments in Hatton resulted in navy bean blemishes and discoloration, and not observed at other locations and varieties. Pinto beans were planted at Prosper and Hatton, ND. At Propser and Hatton, Desicate II and Valor, caused more than 85% leaf desiccation 7 days after application comparted to 68% and 73% desiccation in untreated plots at the two locations. Desicate II and Valor, caused more than 45% vine desiccation at Prosper and greater than 53% in Hatton 7 DAA compared to 25% vine desiccation in the untreated check Prosper and 43% in Hatton 7 days after application. At Prosper, seed moisture ranged 14 to 21% in the treated plots and untreated at 23% 7 DAA. Seed moisture in Hatton ranged 13 to 15% and the untreated at 18% 7 days after application. A complimentary study was conducted in Erie, ND, to evaluate endothall and flumioxazin with adjuvants in navy bean. Endothall plus ammonium sulfate with or without a methylated seed oil (MSO) + basic blend (BB) adjuvant did not affect leaf and vine desiccation. Valor applied at 1.5 oz/A with MSO + BB adjuvant did not increase dry bean desiccation compared to 1 oz/A. Desicate II and Valor consistently gave greater and more rapid desiccation at all locations than other herbicides.