selected based on their relevance to the application of the BMP in reducing nutrients in runoff or irrigation water losses for container-grown plants. Results and discussion In this paper, for consistency, we will refer to each BMP by number as they are
Transplants of `Ohio 8245' tomato grown in 48-cell plastic trays received 5 potassium chloride concentrations and were stressed by withholding water during the 6th week of growth. Gravimetric water loss differed between treatments with decreased water loss associated with increased potassium chloride concentration. As water was withheld, incidence of wilt was greater and more evident at an earlier stage with plants supplied with lowering KCL concentrations. Root and shoot dry weights, plant height and leaf area were not affected by treatments. This indicates an apparent increase in water use efficiency in tomato transplants supplied with KCL at greater concentrations than supplied under standard fertilizer regimes.
Plantlets of Solarium tuberosum L. `Russet Burbank', `Sangre', and `Centennial Russet' were grown in vitro from nodal cuttings. A medium overlay was used to reduce the humidity of the in vitro environment. This treatment was tested for its effect on plant growth and on the rate of water loss from detached leaves. The latter was assayed as indicative of hardening and consequent survival of plantlets once removed from in vitro culture. The paraffin medium overlay reduced the rate of water loss from detached leaves of cultured plantlets, but also reduced root growth.
Freeze-damaged ‘Valencia’ oranges [Citrus sinensis (L.) Osbeck] were tightly covered with polyethylene bags while still on the tree, and their dehydration rates were compared to those of nonbagged fruit. The bags significantly reduced water loss from fruit over a period of 11 weeks after the freeze. After fruit were harvested and removed from the bags, previously bagged fruit had higher water loss rates than nonbagged fruit. These data indicate a significant amount of water in the fruit is lost through the peel after freeze damage has occurred. The dryness cut method did not quantitatively determine dehydration of freeze-damaged oranges.
evapotranspired water ( W ET ), water loss ( W L ), total water use ( W use ), number of nutrient solution discharges (flushing events), leaching fraction (LF = W L / W use ), and loss of nutrient ions (NO 3 − , K + , and PO 4 3− ) of Hippeastrum grown in
of water ( Ye et al., 2016 ), can aid in reducing water loss and improving crop yields ( Khodadadi Dehkordi, 2016 ). Many studies have shown that different types of SAPs have varying effects on soil, water retention, and fertilizer retention; however
Reduced atmospheric pressures may be used to minimize mass and engineering requirements for plant growth habitats used in some extraterrestrial applications. A chamber with high vacuum capability and thermal control at Kennedy Space Center was used to measure water loss of lettuce plants at reduced atmospheric pressures. A test stand with three, high-pressure sodium vapor lamps was used to determine short-term plant responses to reduced pressure. Initial experiments with lettuce showed that a pressure of 10 kPa (≈0.1 atm) resulted in a 6.1-fold increase in the rate of water loss compared to water loss at ambient pressure. However, due to low relative humidity, plants wilted after 30 minutes exposure to 10 kPa. A follow-up experiment in which relative humidity was controlled between 70% and 85%, demonstrated that water loss was directly proportional to the vapor pressure gradient, regardless of atmospheric pressure in the pressure range of 10 to 101 kPa. However, the response was curvilinear, suggesting effects on the pathway resistance. Results indicate that plant growth at atmospheric pressures of 5 to 10 kPa should be achievable. Further work will necessitate better relative humidity control and carbon dioxide control in order to separate vapor pressure deficit effects from diffusion effects.
A simple to use, accurate, inexpensive, recording evaporation gauge for lysimetric studies with plants in small containers is described. Water losses as large as 264g/day, and as small as lg/hr, were recorded in seedling geraniums grown in a peat-lite medium in 10-cm plastic pots from Jan. 31 to May 23, 1970.
Quality of deciduous tree fruits is determined by several factors, including appearance (size, shape, color, absence of decay and other defects), texture, flavor, and nutritive value. Harvesting methods, especially those involving a once-over procedure, may determine uniformity of maturity at harvest, which, in turn, influences these quality attributes. Maturity also affects susceptibility of the fruit to water loss and mechanical injury.
Sixty-two agents were tested for their ability to prevent chilling injury of bananas (Musa sapientum L.). Postharvest treatment of dimethylpolysiloxane, safflower oil, and mineral oil were effective in preventing underpeel discoloration of banana from up to a 48 hr treatment at 9°C (48°F). Increased shelf life and decreased water loss occurred after treatment.