Sign up for email alerts of new Fluid Journal issues!
Fluid Journal : Fluid Journal 1996-1998
2 Fluid Journal Fall 1995 Favorable weather conditions existed through mid and late summer. Though average populations were near or below the minimum proposed as necessary to maximize yield, yields were excellent and seemingly unaffected by the reduced plant populations. Frost damage. In 1995, the June 13 planting was not completely mature when killing frost occurred on September 21. Though yields for this planting were good to excellent, harvested seed contained significant frost-damaged beans. Hybrid variance. In 1995, average frost damage was 13 percent for Bill Z pinto and 21 percent for Midland navy. It is uncertain how much of the yield reduction for the June 13 planting resulted from frost and how much was caused by other environmental factors. The reduction was likely greater for Midland than for Bill Z. Green pods were still present on Midland at the time of frost, but almost all of the pods on Bill Z had matured. Mean yields were significantly greater for Bill Z pinto than Midland navy for all planting dates in both years (Figures 1 and 2). Bill Z plants were larger at V4 for all planting dates, but by flowering (RI), Midland plants were larger. Dry matter at pod fill (R8) was similar between varieties in 1994 and greater for Bill Z in 1995. Growth. Early growth was greatest for late plantings but did not translate to greater yields in 1995. Early plantings emerge and grow slowly during cool weather. Flowering and pod fill then occurs during warm weather and long days. Late plantings grow rapidly during warm summer days but flower and fill pods during shorter (and usually cooler) late summer and early fall days. September temperatures were warmer than normal in 1994 and allowed late plantings to fill pods during warmer conditions. Disease incidence. In 1994, disease symptoms were present throughout the plot but were most severe in the May 10 planting. Hot, dry winds during flowering seemed to cause some flower abortion, but no data were collected to verify this observation. Irrigation immediately after the May 10 planting created cold, wet soil conditions during germination and seedling development. Emergence time was longest for this planting and probably reflected conditions created by irrigation. Irrigating after this planting probably contributed to a greater incidence of Yield - bu/A 4,500 4,250 4,000 3,750 3,500 3,250 3,000 2,750 2,500 May 11 Planting Date Figure 2. Dry bean yield response to planting date at Powell, WY, 1995. May 19 May 30 June 13 Bill Z. Midland 4,000 Yield - lbs/A 1994 1995 3,800 3,600 3,400 3,200 3,000 2,800 2,600 0 0 20+0+0 20+0+0 N + P2O5 +Zn formulation - lbs/A Figure 3. Dry bean yield response to starter fertilizers at Powell, WY. 20+0+0 20+0+0(bc)
Fluid Journal 1993-1995
Fluid Journal 1999-2001