In March 1992 treatments were established in a split plot design to compare vegetable yield and nutrient buildup effects of 94 kg of 34-0-0, 1345 and 2692 kg/ha spent poultry litter under fallow or wheat rotation cover. The 2692 kg litter treatment caused a nonsignificant decrease in `Crimson Sweet' watermelon yield. Wheat was planted on half the plot area in September 1992 and harvested in March 1993. Fertilizer and litter treatments were reapplied in April and `Merit' sweet corn was planted. Corn plant growth was more vigorous and yield was significantly higher in fallow plots irrespective of litter treatment. Sweet corn yield was highest in plots treated with 2692 kg liter/ha. NO3, K, SO4, and Mg content of the top 30 cm of soil was decreased by wheat. Soil nitrate level remained below the pretreatment level after the first year except for the 2692 kg litter/fallow treatment. Soil P at the 0-30 cm depth remained the same as or higher than the initial level in all treatments. Soil K content exceeded initial test levels in all fallow treatments and one wheat treatment.
B.D. McGraw and B. Bostian
L. Brandenberger, L.K. Wells, and B. Bostian
Because of the limited number of herbicides in spinach, beet, and swiss chard, a screening study was initiated to identify new preemergence herbicides. Field soil at the study was a fine sandy loam. The study was initiated on 8 Apr. 2004 at Bixby, Okla. Each plot had four direct seeded rows of spinach, beet and chard. 22 treatments were replicated four times in a RBD that included a nontreated check. Treatments used 12 preemergence herbicides. Herbicides were applied PRE with a research sprayer at 20 GPA in a 6-ft swath perpendicular to crop rows. The experimental area received 0.5 inch of irrigation after application. Callisto (mesotrione) and V10146 (Valent exp. compound) both resulted in 100% death of beet, chard and spinach seedlings. Herbicides that had injury at or below Dual Magnum included Pyramin (pyrazon), Nortron (ethofumesate), Lorox (linuron), and Bolero (thiobencarb) tank-mixed with Bio-Power. Yields were zero for the nontreated check and several treatments due to weed competition and the lack of crop plants in some plots. Treatments with the highest beet yields included Dual Magnum at 0.5 lbs/acre, Pyramin at 3.6 lbs/acre, and Outlook (dimethenamid-P) at 0.25 lbs/acre (11,822, 8,034, 8,010 lbs/acre respectively). Highest chard yields were from Dual Magnum at 0.5 lbs/acre, Pyramin at 3.6 lbs/acre, Outlook at 0.5 lbs/acre + Bio-Power, and Outlook at 0.5 lbs (12,753, 12,596, 11,495, and 10,563 lbs/acre, respectively). Spinach yields were highest for Dual Magnum at 0.5 lbs/acre, Define (flufenacet) at 0.3 lbs/acre, and Outlook at 0.5 lbs/acre + Bio-Power (4,465, 4,259, and 3,207 lbs/acre, respectively).
J.E. Motes, B. Bostian, and N. Maness
The objective of this study was to evaluate the possible causes for greater pungency in pepper (Capsicum annuum) pods of two chile selections when produced at eastern and western Oklahoma locations. Pungency tests over several years have demonstrated that peppers grown in western Oklahoma consistently produce pods with ≈25% greater pungency than peppers grown in eastern Oklahoma. Data from Oklahoma Mesonet stations located near each production location indicated the western Oklahoma location had higher temperatures and wind speed but lower relative humidity than the eastern Oklahoma location during pod development. Mature dry pods were dissected into cap and stem, seeds, and pod wall. Comparisons of pod component differences between the locations showed pods were similar in dry weight; however, western Oklahoma produced more cap and stem in both selections, and in one selection produced more pod wall but less seed. Pungency was 24% and 28% greater in the two selections when grown in western Oklahoma. More pod wall and less seed could account for some of the pungency increase in only one of the selections. The more stressful production environment in western Oklahoma appears to be the major factor in pungency differences between the locations.
Lynn P. Brandenberger*, Lynda K. Wells, and Bruce B. Bostian
The objectives of this trial were to collect yield and quality data on a fall planted carrot trial. Fifteen different carrot varieties were included in the trial. Plots were 20 feet by 2.5 feet and consisted of two rows of carrots with 15-inch row centers. Plots were replicated 4 times in a RBD. Carrots were direct seeded on 8 Aug. 2003 at 20 seeds per foot. Plots were fertilized with 90 lbs/acre of nitrogen and received overhead water as needed. Yield and quality data were recorded on 5 Dec. 2003. Data included exterior root color, interior root color, percentage of split and forked roots, overall yield, average root length and weight. Exterior root color did not vary significantly for any of the cultivars in the trial, but interior root color varied significantly for several cultivars. `First Class', `Bolero', and `C 7105' had the most distinct differences between the pith and out ring colors as indicated by the interior root color ratings and `Ingot' had the lowest. Interior root color ratings for these four cultivars were 3.8, 3.6, 3.1, and 1.4, respectively. Crispness did not vary for either the initial or second ratings that were recorded. Of potential defects only the percentage of forked roots varied significantly and of these four cultivars had less than 10% forked roots. `Florida', `Kamaran', `Pipeline', and `C 7105' had 5%, 7%, 9%, and 9% forked roots, respectively. `Samantha' had 31% forked roots, the highest percentage recorded in the trial. No differences were recorded for root weight, diameter or length. The three highest yielding cultivars in the trial were `Ingot', `Heritage', and `Neptune' that had overall yields of 24.9, 20.6, and 20.6 tons/acre. `Bremen' recorded the lowest yield in the trial with 13.7 tons/acre.
L. Brandenberger, L.K. Wells, J. Sanchez, and B. Bostian
Trials were conducted to determine southern pea performance in two different production environments in Oklahoma. Plots consisted of one row 20 feet long with 30 or 36 inches between rows. Seed were spaced 10 seed per foot and were inoculated with Rhizobium at planting. The trials were seeded on 15 June 2004 at Bixby, Okla. (elevation836), and on 16 June 2004 at Goodwell, Okla. (elevation 3293). Trials included at least three replications in a RBD for the 15 cultivar/breeding lines. Plots received a PRE application of Dual Magnum at 1.0 lb ai/acre tank-mixed with Pursuit at 0.063 lb a.i./acre. Supplemental water was applied with overhead irrigation. Maturity before harvest was rated as percentage of dry pods. TX158BEgc, LA 96-4, and US-1076 had the highest percentage of dry pods at both Bixby and Goodwell for blackeye, cream, and pinkeye types, respectively. Yields are given as imbibed lb/acre. Peas with consistent yields at both Bixby and Goodwell included blackeye types AR 00-178 with yields of 2,558 and 4,738 lb/acre, respectively, and ARK Blackeye #1, which had yields of 2,605 and 4,406 lb/acre, respectively. The highest yielding cream type at Bixby was LA 96-4, at Goodwell it was Early Acre, these had yields of 2,346, and 3,983 lb/acre, respectively. The highest yielding pinkeye types included AR 96-854 at Bixby and AR 01-1293 at Goodwell which yielded 3,593 and 4,366 lb/acre, respectively. LA 96-18 had yields of 2,886 and 2,853 lb/acre at Bixby and Goodwell, respectively, and was the most consistent yielding pinkeye for both sites.
N.E. Maness, J.E. Motes, B. Bostian, and R.J. Schatzer
Sage is a perennial, semi-evergreen herb and is a multiharvest crop. In a 4-year field study in Bixby, Okla., three N rates, including 60, 120, and 180 kg/h, and four fall harvest dates, including 40 and 20 days before the average first freeze date in Bixby, the average freeze date, and 20 days past the average freeze date were evaluated on sage (Salvia officinalis) production. The fall harvest dates were ≈20 Sept., 10 Oct., 1 Nov., or 20 Nov. each year. Plots were established with transplants in Spring 1990. On all plots, growing-season harvests were executed once in spring and once in summer, followed by the final harvest in the fall annually (1991 to 1994). Results indicated N effects on yield and the N × final fall harvest date interaction were not significant for any of the years. Yields were significantly reduced in the 40 and 20 days prefreeze date harvest treatment plots in 1992, 1993, and 1994 by a hard freeze of –7C on 2 Nov. 1991 with no prior killing frost. Plant stand loss was 61% and 8% in the 40 and 20 days prefreeze harvested plots, respectively. Injury, but not plant loss, in the 20 days prefreeze harvested plots contributed to the yield reduction. Yields in the two later final harvest treatment plots were not affected.