Premium
Chemical aids to drying seeds of beans (Phaseolus vulgaris) before harvest
Author(s) -
HOLE C. C.,
HARDWICK R. C.
Publication year - 1978
Publication title -
annals of applied biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.677
H-Index - 80
eISSN - 1744-7348
pISSN - 0003-4746
DOI - 10.1111/j.1744-7348.1978.tb00734.x
Subject(s) - phaseolus , diquat , water content , biology , horticulture , agronomy , moisture , crop , zoology , paraquat , chemistry , biochemistry , geotechnical engineering , organic chemistry , engineering
SUMMARY The effects on seed moisture content of seven different chemical formulations applied to bean (Phaseolus vulgaris) crops in two successive years were observed. Those containing bipyridyl herbicides caused the biggest effects. In 1974, diquat (0–59 kg a.i. ha ‐1 ), applied to a French bean crop cv. Processor 26 days before harvest, decreased seed moisture content by 98 mg g _1 dry weight below a control value of 438 mg g _1 . In 1975, diquat applied at the same rate to a navy bean crop cv. Seafarer 16 days before harvest, decreased seed moisture content by 123 mg g _1 below a control value of 364 mg g _1 . Diquat applied at a lower rate (0–3 kg a.i. ha ‐J ) caused a decrease of 79 mg g _1 and paraquat decreased seed moisture by 147 mg g _1 . In both years smaller effects were observed for dimexan (15 kg a.i. ha ‐1 ) which decreased seed moisture content by 32 mg g ‐1 in 1974 and 72 mg g _1 in 1975 and for ethephon (1‐0 kg a.i. ha ‐1 ) which caused decreases of 78 mg g _1 in 1974 and 31 mg g _1 in 1975. In 1975, metham‐sodium (70 kg a.i. ha ‐1 ) a soil sterilant, proved almost as effective as the bipyridyls, decreasing moisture content by 105 mg g _1 . Trimming the roots mechanically reduced seed moisture by 67 mg g _1 . Other chemical treatments, tried in 1975 only, were less effective and decreased seed moisture content by 31–60 mg g _1 . These were Wiltz‐65 (pentanoic and hexanoic acids, 14‐6 kg a.i. ha ‐1 ), N252 (dihydro‐dimethyl‐dithiin tetroxide, 0–56 kg a.i. ha ‐1 ) and an application of diquat (0–3 kg a.i. ha ‐1 ) to plants treated 10 days before with ethephon (1‐0 kg a.i. ha ‐1 )‐ In addition to the effects on seed moisture content, all treatments decreased seed yield. The largest decreases were caused by diquat and were attributable mainly to effects on mean seed weight. The paper concludes with an economic analysis which shows that at present prices chemical drying of beans in the field is not worthwhile because the yield loss nullifies any savings in drying costs.