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- Author or Editor: John D. Abbott x
- HortScience x
Abstract
Roots of flooded highbush blueberry (Vaccinium corymbosum L.) plants examined by light and scanning electron microscopy exhibited enlarged epidermal cells, compressed cortical cells, and disrupted vascular tissue. The stems of flooded plants showed disrupted epidermal tissue, condensed outer cortical cells, and large aerenchyma-like mid-cortical tissue. Leaves from flooded plants showed an increase in intercellular spaces in the spongy mesophyll and a disrupted palisade layer. There were no apparent differences in inflorescence bud anatomy, although inflorescences were small and delayed in development.
Abstract
Two-year-old container-grown highbush blueberry plants (Vaccinium corymbosum L. ‘Bluecrop’) were flooded outdoors, beginning in December, April, and August, to determine the seasonal effects of root-zone flooding on reproductive growth. Flooded plants had 61-77% fewer flower buds and 55-66% fewer flowers per bud, compared to nonflooded plants. Anthesis was delayed about 6 days in flooded plants. Fruit set was decreased 45% and fruit abscision increased with flooding. Fruit weight, fruit size, and percentage of soluble solids from flooded plants were reduced significantly.
Abstract
Watered split-root portions of 2-year-old plants of ‘Bluecrop’ blueberry (Vaccinium corymbosum L.) exhibited significantly greater shoot dry weight, shoot thickness, shoot length, mean number of shoots, and leaf dry weight than nonwatered portions. Watered portions blossomed, produced fruit, and set new flower buds while existing flower buds died and no new flower buds formed on the nonwatered portions.
Four fungicides were evaluated for their effects on in vitro pollen germination of muskmelon (Cucumis melo L.) cultivars TAM-Uvalde and Magnum 45. Cupric hydroxide, mancozeb, and chlorothalonil reduced the percentage of pollen that germinated and rate and length of germ-tube elongation, regardless of cultivar. Benomyl had very little overall effect on pollen germination or germ-tube elongation. With the effective pollination period of ≈ 10 to 14 days in commercial production, each day is critical for maximum crown set. Based on our results. some fungicides may be contributing to reduced fruit set in muskmelon.
Three cold-climate strawberry production systems, conventional matted row, advanced matted row, and cold-climate annual hill plasticulture, were compared for consumer preference in a pick-your-own (PYO) setting. Replicated 6 × 15 m plots were established in 2002 in Maryland and cropped in 2003 and 2004. To simulate PYO marketing, volunteers were recruited to harvest 3.6-m plots in each of the three production systems and to complete a five-part questionnaire. The questionnaire collected demographic information and allowed volunteers to compare the three systems both prior to and after their harvesting experience. Harvests were carried out twice weekly, with 75 participants in 2003 and 45 participants in 2004. The 2003 season was cool and wet, with frequent rainfall and a high incidence of fruit rot. Spring 2004 was unseasonably hot, resulting in an unusually short harvest season. Consumer preference differed between years and among harvests within a season. The annual hill system was favored early in the 2003 season, with preference shifting to the other systems as the season progressed. The advanced matted row was favored early in the 2004 season. Many of the participants' comments, both positive and negative, were directed at the plastic mulch and raised beds. In several cases, participants indicated that their preferences after picking from each system did not match their initial impressions. Implications of this research to the social components of sustainability will be discussed.
Abstract
Crack-susceptible and crack-resistant tomato (Lycopersicon esculentum L. Mill.) cultivars were grown in soil beds and in bags filled with a peat-vermiculite mix. Plants in soil were drip-irrigated 1 or 4 times daily, or hand-watered every day or as needed based on soil moisture tension. Plants in bags received only drip-irrigation treatments. Genotype had the greatest effect on fruit cracking, with 3.8% by weight cracked fruit in the crack-resistant compared to 35.3% in the crack-susceptible cultivar. Growing plants in bags reduced the weight and the percentage of cracked fruit per plant, but, in both cultivars, total and No. 1 fruit weights were greatest from the soil treatments with drip-irrigation. Irrigation frequency and method did not affect fruit weight except in the crack-resistant cultivar grown in bags where increasing irrigation frequency increased weights. Cracking was decreased by 22% in tomatoes irrigated manually every day, compared to those irrigated only when needed. In the soil treatment, raising the irrigation frequency significantly decreased cracking in the susceptible, but not in the resistant cultivar. In the soilless treatment, frequent irrigation increased cracking in both cultivars.