Thouron of Pennsylvania, Dick Ryan of South Africa, and Glasshouse Works, Ohio, and added to the program. In 1984, a seedling from a 1980 cross bloomed with keeled tepals. This was unexpected, and led to new breeding goals of multipetaled flowers and
Large weeds, particularly amaranths, are a serious impediment to mechanical harvesting of jalapeno peppers. Several herbicides were applied in 1998 and 1999 postemergence topical (PT) to commercial fields when peppers had four to six leaves, or postdirected (PD) with a shielded sprayer ≈1 month later, and evaluated for crop injury, weed control, and effects on yield. Treatments were applied to four-row plots 9 m long with a CO<subscript>2 backpack sprayer. PT treatments included pyrithiobac sodium at 0.036, 0.053, or 0.071 kg·ha–1 a.i. with nonionic surfactant or crop oil concentrate, metolachlor at 1.68 kg·ha–1 a.i., and oxyfluorfen at 0.14 or 0.28 kg·ha–1 a.i.. PD treatments consisted of the same rates of pyrithiobac sodium with nonionic surfactant only, and the same rates of oxyfluorfen. Pyrithiobac sodium PT caused significant chlorosis (reduction in SPAD chlorophyll) in new foliage and reduction in plant height after 1 week, but plants recovered with no effect on final plant height, chlorophyll, or yield. No significant difference was observed between the two adjuvants. Metolachlor had no measurable effect on pepper growth or yield. Oxyfluorfen PT killed young apical tissue and caused chlorosis of immature leaves. Plants recovered, but plant height was reduced by 14% to 28% and yield by 11% to 43%. PD treatments had no effect on pepper growth or yield. All herbicides provided adequate weed control under light pressure. Pyrithiobac sodium appears to have potential as a postemergence herbicide for control of amaranth in jalapeno peppers.
Several experiments were conducted to determine release rates of five oxadiazon-coated fertilizers. Five fertilizers and 4-mm glass beads (nonabsorbent control) were coated with 14C-oxadiazon + formulated oxadiazon, then placed in a separatory funnel and leached with 20 ml of water for 14 days. 14C-oxadiazon was quantified by use of liquid scintillation spectrometry. For glass beads, Nutricote, Meister, and Osmocote, 70% to 80% of the 14C-oxadiazon was recovered in the first two leaching events. Oxadiazon leached from Polyon was 47% during the first two events and remaining oxadiazon was slowly released over the next 12 leaching events. 14C-oxadiazon from the other fertilizers over the last 12 days of leaching was less than that recovered from Polyon. Evaluation of the total surface area of a 50-g sample revealed Polyon had the greatest total surface area of the five fertilizers. Scanning electron micrographs before and after leachingindicated potential erosion of the Polyon surface compared to little or no change in the surfaces of the other fertilizers.
1 Professor. 2 Research Specialist. Appreciation to Seth Combs, Heath Combs, Jean Engleman, Maurice Keeler, and Harriet Keeler for data collection, analysis, and technical assistance.
Abstract
Lima bean, Phaseolus lunatus cv. Early Thorogreen, is primarily self-pollinated. Morphological characteristics of reproductive structures which facilitate self-pollination include the stage of floral development at the time of anther dehiscence and the relative positions of anthers and stigma within the keel at the time of pollen shedding. Coincidental maturation of pollen and receptivity of the stigmatic surface also enhance the capacity for self-pollination. The varying degrees of cross-pollination frequently reported may be facilitated by extrusion of the stigma from the keel, which occurs in connection with insect visitation at an thesis, and also by the prolonged period of stigma receptivity, which extends from the white bud stage through anthesis.
, Valent BioScience Corp., Libertyville, IL, and AgroFresh Inc., Spring House, PA. Appreciation to Maurice Keeler, Harriet Keeler, Jean Engelman, and Tim Stern for data collection, and technical assistance.
Abstract
Frequency of natural hybridization of P. vulgaris and P. coccineus was observed over two seasons. Natural hybridization ranged from zero to 6.79%, and was dependent upon parental combination. Bumblebees appeared to be the principal insect pollinators. The best P. coccineus pollen parent, P.I. 223803, had scarlet flowers and was relatively early in maturity. The P. vulgaris cultivar which hybridized most frequently, ‘Tender-green’, had a high frequency of atypical flowers. In many of the atypical flowers the standard and keel petals were not fully developed, thereby leaving the reproductive parts exposed to insect pollinators. It is suggested that natural hybridization might be useful in transferring P. coccineus genes for disease resistance into P. vulgaris lines.
broadest, densely striated RHS red–purple 57A, especially the upper, with darker markings at the throat ( Table 2 ), and faint RHS white 155D keels; margins are irregularly RHS white 155D. Tepal outer surfaces are more lightly striated with infusions of RHS
). The standard form is entire, 4.5 cm long and 5.8 cm wide. The wings are moderately incurved, 3.9 cm long, and 3.2 cm wide. The keel is 2.7 cm long and 1.5 cm wide. Pistil is present. Calyx is campanulate and not pigmented. The density of
proportionally reducing carrier volume with herbicide rate may yield unrealistic results and confound the results obtained ( Everitt and Keeling, 2009 ; Marple et al., 2008 ). Visual ratings of plant injury based on a scale of 0 (no effect) to 100 (plant death