Methiozolin is a new isoxazoline herbicide being investigated for selective POST annual bluegrass control in creeping bentgrass putting greens. Glasshouse and field research was conducted from 2010 to 2012 in Tennessee and Texas to evaluate annual bluegrass control efficacy with methiozolin. Application placement experiments in the glasshouse illustrated that root absorption was required for POST annual bluegrass control with methiozolin at 1,000 g ai ha−1. Soil-plus-foliar and soil-only applications of methiozolin reduced annual bluegrass biomass greater than treatments applied foliar-only. Field experiments evaluated annual bluegrass control efficacy with two application rates (500 and 1,000 g ha−1) and six application regimes (October, November, December, October followed by [fb] November, November fb December, and October fb November fb December) on sand- and soil-based putting greens. Annual bluegrass control with methiozolin at 1,000 g ha−1on sand-based greens ranged from 70 to 72% compared to 87 to 89% on soil-based greens. Treatment at 500 g ha−1controlled annual bluegrass 57 to 64% on sand-based greens compared to 72 to 80% on soil-based greens. Most sequential methiozolin application regimes controlled annual bluegrass more than single applications. On sand-based greens, sequential application programs controlled annual bluegrass 70 to 79% compared to 85 to 92% on soil-based greens. Responses indicate that methiozolin is a root-absorbed herbicide with efficacy for selective control of annual bluegrass in both sand- and soil-based creeping bentgrass putting greens.

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Cherry trees display vigorous upright growth, which tends to reduce precocity, flower bud formation and fruit quality. Three trials were performed in the 2010-2011 season on mature 'Lapins' and 'Sweetheart' sweet cherry trees in the Angol area (37°48'50"S, 72°37'36"W). The effects of prohexadione calcium (P-Ca) on shoot growth, leaf area, yield, fruit quality and flower differentiation were assessed. Two rates were evaluated (150 mg L-1 and 250 mg L-1), which were sprayed when shoots were 15 cm long and 15 days later or after harvest. The P-Ca treatment reduced the elongation of terminal shoot in both cultivars, which was due to reducing both length and number of internodes, resulting in a reduction in total leaf area. This led to better light penetration and distribution in tree canopies. Applications of P-Ca to shoots 13 to 15 cm in length controlled shoot growth adequately, while the effect was excessive when the spray was repeated after 15 days. No additional effect was detected when the second application was applied after harvest. P-Ca treatments increased the number and size of reproductive buds and the number of floral primordia per bud. The development of floral structures in the buds was more advanced compared to the control. Regarding fruit quality, soluble solids concentration and fruit size there were no significant effect from P-Ca application, while the fruit firmness increased. One single application of P-Ca at 250 mg L-1 in spring appears to be the most effective treatment to control vegetative growth, to increase the number of flower buds and to improve fruit firmness.

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Indaziflam is an alkylazine herbicide that controls winter and summer annual weeds in bermudagrass (Cynodon sp.) turf by inhibiting cellulose biosynthesis. Research was conducted in Tennessee and Texas during 2010 and 2011 to evaluate the effects of indaziflam applications on overseeded perennial ryegrass (Lolium perenne) establishment and summer annual weed control. In Texas, perennial ryegrass cover on plots treated with indaziflam at 0.75 and 1.0 oz/acre measured 37% to 48% compared with 88% for the untreated control 257 days after initial treatment (DAIT). Perennial ryegrass cover following applications of indaziflam at 0.5 oz/acre measured 84% 257 DAIT and did not differ from the untreated control on any evaluation date. Inconsistent responses in crabgrass (Digitaria sp.) control with indaziflam at 0.5 oz/acre were observed in Tennessee and Texas. However, control was similar to the 0.75-oz/acre rate and prodiamine at 7.8 oz/acre at each location. A September application of indaziflam at 0.75 oz/acre followed by a sequential treatment at 0.5 oz/acre in March of the following year provided >90% control by June 2011. Indaziflam application regimes of this nature would allow for successful fall overseeding of perennial ryegrass every two years and control winter annual weed species such as annual bluegrass (Poa annua).

The effect of decreasing levels of organic N-fertilization on fruit production, mineral composition and fruit quality was evaluated in organically cultivated "Granny Smith" apples trees. Treatments included the application of decreasing levels of N fertilization (100 kg N ha -1 , 75 kg N ha -1 , 50 kg N ha -1 and 0 kg N ha -1 ) applied as fossilized red guano (50% of the total amount of N) and blood meal (50% of the total amount of N) to twelve years old Granny Smith apple trees. Yield was not affected by the treatments (yield ranged from 0.28 to 0.4 kg cm -2 SCSA). Fruit mineral concentration and ratios were not affected by treatments. Fruits showed low Ca concentrations (2.8 to 3.3 mg Ca 100 g -1 FW), high levels of K (118.6 to 130.1 mg K 100 g -1 FW) and high values for K+Mg/Ca (> 12) and K/Ca (> 30) ratios. Mineral concentration on leaves was not affected by treatments (normal concentrations for macro and microelements). Bitter pit was only detected after 60 days of storage (100 kg N ha -1 tree, 1.1 in a scale 1-4). Besides orchard nitrogen management, fruit mineral ratios and Ca foliar applications should be considered for managing fruit production and quality in organic apples.