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  • Author or Editor: L. Chapman x
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Pecan nuts from eleven different locations ranging from 1000 heat units at Chetopa, Kansas during the twelve weeks prior to shuck split to 1675 heat units in Zavala County, TX. Monounsaturated and polyunsaturated fatty acids increased and decreased respectively in `Mohawk' in 1991 and 1992 as the temperature increased during the kernel development period Fatty acids in `Pawnee' responded the same as in `Mohawk' in 1992 but were variable in 1991. Limited data showed a reversal of mono and polyunsaturated fatty acids in `Osage' in response to kernel development temperature. Higher temperatures caused the testas of `Cheyenne' to be darker in 1991 and 1992. Total oil content of `Mohawk' increased heat units. However, higher temperatures decreased oil content in `Pawnee'. Clinical evaluation of pecans is needed to confirm Grundy's safflower work.

Free access

Four year old `Loring' peach trees on `Lovell' rootstock were treated with single applications of 0, 50, and 100 ppm GA3 alone and in combination with 100 ppm ethephon on 15 November 1988, 1989, and 1990 to determine the effect on bloom delay the following spring. Flower bud number was not affected by any of the treatments the next spring. Ethephon had the greatest effect on bloom delay the following spring. The 50 and 100 ppm GA3 treatments resulted in a slight delay of bloom. The combination of 50 and 100 ppm GA3 and 100 ppm ethephon resulted in less of a bloom delay than ethephon alone but greater than the GA3 treatments alone. Fruit set was increased by ethephon treatments in 1989 and 1991 but not in 1990. Ethephon treatments delayed fruit maturity whereas GA3 did not. Total fruit yield for 1989, 1991, and the three year average was not effected by treatments. However, in 1990 50 ppm GA3 resulted in the highest yields. Ethephon treatments reduced the average fruit weight in 1990 and 1991 but not in 1989 or the three year average.

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Abstract

‘Atlas’ and ‘Monika’ alstroemeria (Alstroemeria hybrida L.) were grown in cooled (12 to 16C) and noncooled (15 to 18C) gravel substrate in four temperature-controlled greenhouse compartments having mean day/night air temperatures of: 20/14, 20/13, 22/13, and 24/14C. Total flower production of ‘Atlas’ in all compartments was 1.6 times greater than for ‘Monika’. The greatest production of ‘Atlas’ occurred with 20C average daytime air temperatures combined with root substrate temperatures 12C to 14C, which favored year-round production. Warmer day temperatures tended to improve flower grade and stem length of ‘Monika’; however, the higher yield in cooler air temperatures outweighed the contributions of warmer air temperatures to quality. ‘Atlas’ stems were significantly longer and of better quality than ‘Monika’ in all temperature regimes.

Open Access

The primary goal of this study was to determine the optimum number of substrate moisture sensors needed to accurately determine substrate water content for 10 tree species in a containerized nursery. We examined variation in volumetric water content (VWC, m3·m−3) within containers, within species, among species, and over time. Across time, differences among species were not significant (P = 0.14). However, differences among time periods and the interaction effect between species and time periods were significant (P < 0.001). Seasonal differences in within-species variation were also evident in nine of the 10 species. In an attempt to understand species-specific mechanistic factors that influence within-species variation in VWC, we accounted for physiological and morphological differences affecting transpiration with a spatially explicit mechanistic model, MAESTRA. Neither estimated transpiration rate per whole crown or m2 of leaf area could explain variation in VWC. Based on our results, we recommend species-specific sensor deployment and report sensor quantities that estimate the mean substrate VWC of each species within a confidence interval of ± 5% VWC. Given the economic value of water and its control on biomass production, we conclude that nursery managers can maintain optimal substrate moisture with minimal sensor deployment.

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This study was carried out to determine the influences of planting date (June, July) and soil applications of Trichoderma harzianum (strain T-95) and a fungicide containing ethazole + thiophanate (BanrotR) on flower production of standard carnation cvs. Improved White and Tanga. The one-year production data showed that the fungicide treatment increased flower yield by 7.3% (33.5 flowers/m2) and 4.8% (23.3 flowers/m2) in Improved White and Tanga, respectively, for June planting. Improved White produced more flowers and fancy grades when planted in July as compared to June planting. Planting date did not influence either the yield or the flower quality in Tanga. The effectiveness of Trichoderma as a biological control agent on flower yield and quality was not evident. The patterns of weekly flower production for the two cultivars were determined and graphically illustrated.

Free access