Search Results
Abstract
Succinic acid 2,2-dimethylhydrazide (Alar) has been found to have many physiological effects on growth and development of several plant species. (1,3,4,5,6). Hall and Aalders (2) in 1966 reported the effects of this growth regulator on highbush and lowbush blueberries but gave no specific data. These early preliminary data may be of some interest to researchers working with growth regulators.
Abstract
Preharvest spray and postharvest dip treatments of N6-benzyladenine (N6-BA) have been found effective in prolonging storage life of green leafy vegetables (4). It has been suggested that this effect can be explained on the basis of respiration inhibition (1). Dedolph et at (2) observed significant reductions of CO2 evolution and oxygen uptake with N6-BA treated broccoli at 21° and 30°C. Freshly harvested asparagus spears treated with N6-BA and then held in the dark for 136 hours also showed a lower respiration rate as measured by CO2 evolution (1). This compound has also been shown to delay visual manifestations of senescence which occur during storage and was effective in maintaining the green color and appearance of several kinds of vegetables (4). In fruits, Smock et al (3) found that dip treatment or spraying of N6-BA depressed the rate of respiration of apples during the post climacteric phase but accelerated respiration in the preclimacteric phase,
Abstract
Leaves of cultivated highbush blueberry (Vaccinium corymbosum Ait.) displayed a markedly altered anatomical structure following sprays of succinic acid −2,2-dimethylhydrazide (daminozide, SADH). Alterations include an increased number of stomata per unit area, increased length of palisade cells, and a larger, more distinct secondary palisade layer and total spongy mesophyll complex, both of which contributed to increased lamina thickness.
Abstract
A method we have used to study the external characteristics, including stomata, of leaves may be of interest to other horticulturists. We do not know who originated the method but it was first brought to our attention by research workers of United Fruit Company. The method involves making a negative impression of the leaf surface and using the negative to make a positive transparent film which may be studied under a microscope.
Abstract
Preharvest sprays of (2-chlorethyl)phosphonic acid (ethephon) and succinic acid-2,2-dimethylhydrazide (daminozide) and postharvest dips of diphenylamine (DPA) were evaluated for their effects on scald development of ‘Cortland’ apples (Malus domestica Bork.) The total number of scalded fruit and the severity of scald were increased in all years by ethephon treatments. Daminozide treatments reduced scald incidence and severity either alone or in combination with ethephon. DPA dips (2000 ppm) resulted in best scald control. It is postulated that advanced ripeness of the fruit due to ethephon contributed to increased scald incidence.
Abstract
Examination of the cuticle of ‘Cortland’, ‘Mcintosh’ and ‘Golden Delicious’ apple under a scanning electron microscope (SEM) showed differences between cultivars in structure of the wax coating. A possible relationship was observed between wax structure and the occurrence and nature of surface breaks to scald susceptibility. Cuticle thickness had no apparent bearing on susceptibility to scald.
Abstract
Respiration is of primary importance to the plant since it liberates energy to do chemical work in synthesizing energy-rich materials involved in growth. Although the respiratory rate of many plant tissues and organs have been studied (1), no data on respiratory rate of blueberry leaves was found in a search of the literature. It is felt that data on the respiratory rate of highbush blueberry (Vaccinium corymbosum L.) would be of value since it will provide basic information for comparison with other genera.
Abstract
A dichotomous key for the identification of ten commercially important highbush blueberry (Vaccinium corymbosum Ait.) cultivars introduced since 1949 was constructed based on gross morphological characteristics.
Abstract
Highbush blueberries (Vaccinium corymbosum L.) of 7 cultivars were harvested and visually separated into color grades: immature green, mature green, green-pink, blue-pink, blue and ripe. The rates of respiration over a 5 year period and ethylene evolution over a 3 year period of each color grade were determined using an infrared gas analyzer and a gas chromatograph, respectively. The rate of respiration of the berries generally increased from the immature green to a peak at the green-pink or blue-pink stage. Ethylene generally increased to a peak at green-pink. Both patterns are characteristic of climacteric type fruit.
Abstract
Earlier ripening cultivars of blueberry (Vaccinium corymbosum L.) usually produced more vegetative growth flushes than later ripening cultivars. Multiple flower buds were found most frequently on thick wood regardless of cultivar. Most distal buds on any flush were flower buds, while proximal buds were usually vegetative.