Search Results

You are looking at 11 - 20 of 21 items for

  • Author or Editor: R.W. Young x
Clear All Modify Search

Abstract

Accessions, breeding lines, and varieties of Lycopersicon spp. and one accession of Solarium pennellii Correll were evaluated for sensitivity to controlled concentrations of O3 and to ambient air at Waltham, Massachusetts. The plant material was exposed in different stages of development to controlled O3 concentrations of 0.25 ppm for 3 hours, 0.05 ppm for 2 weeks and to 0.10 ppm for 4 weeks. Based upon the degree of foliar injury, the tested material was separated into tolerant, intermediate and sensitive populations. The highest degree of tolerance was observed in L. esculentum Mill, and the highest degree of sensitivity in L. pimpinellifolium. Germination of pollen from inflorescences exposed to 0.10 ppm was reduced 40% in sensitive accessions of L. pimpinellifolium when placed on artificial medium. No significant reduction was observed in the most tolerant accession of L. esculentum. Differences in percent germination were not observed when pollen of sensitive and tolerant accessions was placed on artificial medium and exposed to 0.10 ppm O3 for a six-hour period. Reciprocal cross pollinations between exposed and unexposed populations led to normal fruit development with viable seeds.

Open Access

Abstract

Avocado (Persea americana Mill.) fruit from various locations in California were analyzed for oil and subjected to taste tests every 2 weeks throughout the fruiting season over a period of 5 years. Oil content at acceptable taste differed among cultivars, and the 8% requirement was too low to serve as a good maturity standard for many cultivars. While the date of acceptable taste of fruit grown at the same location was not significantly different from year to year, it varied significantly among and within the widespread avocado production areas. Dry weight, which was highly correlated with increasing oil content, was evaluated as a maturity index. The dry-weight analysis with a microwave oven was much easier than determining oil content. The average dry weight at 8% oil (the existing legal standard in California) was 19.4% for ‘Bacon’, 19.1% for ‘Fuerte’, 19.8% for ‘Hass’, 18.9% for ‘Pinkerton’, and 18.4% for ‘Zutano’ fruit. Dry weight at acceptable taste was 20.0% for ‘Bacon’, 21.0% for ‘Fuerte’, 22.8% for ‘Hass’, 20.0% for ‘Pinkerton’, and 20.2% for ‘Zutano’.

Open Access

Abstract

‘Ouachita Gold’ peach (Prunus persica (L.) Batsch) was released by the Louisiana Agricultural Experiment Station to provide a high quality, large freestone fruit that ripens about 20 days after ‘Elberta’ or about August 5 in north Louisiana.

Open Access

Abstract

‘Majestic’ peach {Prunus persica (L.) Batsch) was released by the Louisiana Agricultural Experiment Station to provide a large, excellent quality freestone fruit in the ripening sequence between ‘Harvester’ and ‘Red Globe’ or from June 22 to July 1 in north Louisiana (1).

Open Access

Abstract

Shading of nectarine [Prunus persica (L.) Batsch] scaffold limbs 45-58 days after full bloom caused seed discoloration and fruit abscission. Shading of peach [Prunus persica (L.) Batsch] scaffold limbs from 31-41 days after full bloom caused greater fruit adscisson than shading from 11-21 or 21-31 days after bloom. The photosynthetic inhibitor, 3-tert-butyl-5-chloro-6-methyluracil (terbacil), applied to whole trees 35 days after full bloom induced fruit abscission. Terbacil at 500 ppm or higher caused excessive thinning. Fruit size was larger than hand thinned fruit, since overthinning occurred. Fruit color, soluble solids, and firmness of fruit from the 500 ppm treated trees were similar to fruit from hand thinned trees. No leaves abscissed, but marginal chlorosis occurred on less than 30% of the leaves at harvest. Flower bud numbers per cm of terminal length were similar to the hand thinned trees, but much greater than unthinned trees. Residue analysis of fruit at harvest from the 500 ppm terbacil treatment revealed 0.07 ppm in the fruit.

Open Access

Abstract

‘La Festival’ peach [Prunus persica (L.) Batsch] was released to provide a yellow flesh cultivar with a good quality fruit requiring 400 to 500 hr chilling. ‘La Festival’ produces a heavy crop of medium to large freestone fruit that ripen about 25 June, or about 20 days before ‘Elberta’ in southern Louisinna

Open Access

Abstract

‘La Pecher’ peach [Prunus persica (L.) Batsch] was released to provide a good quality yellow flesh cultivar with a 400 to 500 hr chilling requirement. ‘La Pecher’ produces a heavy crop of medium to large semifreestone fruit that ripen 39 days before ‘Elberta’ or about 6 June in southern Louisiana.

Open Access

Abstract

‘La White’ peach [Prunus persica (L.) Batsch] was released to provide a 600-700 hr chilling requirement, low acid, white flesh cultivar adapted to conditions in southeastern Louisiana. ‘La White’ produces a heavy crop of medium to large semi-freestone fruit that ripen 27 days before ‘Elberta’ or about 18 June in southeastern Louisiana.

Open Access