A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment... more A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment rate and timing treatments on the growth, yield, berry size and soluble solids of black currants (Ribes nigrum ‘Titania’). Bushes were planted in the spring of 2009 at two sites with black plastic mulch as a weed control without irrigation, and fertilized with seven fertility treatments in either the spring, the summer or split between spring and summer. Rates were 50, 100 and/or 150 kg estimated available N from a blend of crab meal and poultry manure (Nutriwave®). Yield and berry soluble solids were measured in 2010 and 2011. Plants at the site with leaf P and K deficiencies showed lower growth and yield (492-2,540 kg ha-1), but had significant differences in growth response to amendments compared with the site that had adequate levels of P and K, which had no significant difference among treatments in yield in 2011 (3,935-5,016 kg ha-1) or growth among treatments in any of the three years. Where significant differences in growth were found, the medium spring fertility treatment gave the greatest growth and yield, followed by the high spring fertility treatment. The high spring treatment had the highest growth in 2010, but the lowest growth and yield in 2011.
ABSTRACT What is it? The potato crop can be propagated in two ways, vegetatively (clonally) and s... more ABSTRACT What is it? The potato crop can be propagated in two ways, vegetatively (clonally) and sexually (true seeds). Currently, commercial potato production throughout the world is almost completely based on vegetative propagation. True seeds are predominantly used only in breeding work for introduction of new cultivars. Although the potato plant is multiplied using a number of different techniques, in vitro nodal cuttings are probably the most common propagules used in early stages of commercial seed potato production. Since the genetic stability and the production of uniform, true-totype plant material are very important for the industry, the multiplication methods which utilize nodal or apical cuttings and microtubers are preferred in seed potato production. New plants are produced from existing buds assuring identical genetic make-up of the parent plants. In in vitro nodal cutting systems, plantlets are regenerated and multiplied under artificial, aseptic conditions in the laboratory. Depending on the genotype or potato cultivar, 5 to 10 fold multiplication rates per 4 weeks are reported under lab conditions. If virus elimination is needed, cultures are initiated from meristems (dissected portions of the meristematic region of a shoot tip) from plants exposed to a heat treatment or to chemotherapy (i.e. Virozole) prior to culturing. Normally, up to 40% regenerants from meristems are virus-free. Meristems of the treated plants are all disease-free as the pathogens have not been able to enter the less differentiated cells of the meristem. The meristems are then placed on the liquid nutrient media (usually on paper bridges in test tubes) for plant regeneration. They grow into plantlets in approximately 6–8 weeks and then the disease tests are performed on them. Once the disease/virus-free status is determined, the meristem-derived plantlets are used for further rapid multiplication by the in vitro nodal cutting system. The healthy plant material is cut into individual stem portions (single-node
American burnweed is an increasingly common annual weed in wild blueberry fields in Atlantic Cana... more American burnweed is an increasingly common annual weed in wild blueberry fields in Atlantic Canada and Maine. Knowledge of seed dormancy characteristics and potential for this species to form persistent seedbanks in wild blueberry soils, however, is lacking. A series of experiments were therefore conducted to investigate potential mechanisms regulating American burnweed seed dormancy in wild blueberry fields. Seeds were dormant at maturity and did not germinate in dark or light under warm conditions. Cold moist stratification (CMS) at 4 C for 90 d followed by exposure to warm conditions (22/15 C day/night) and light caused >90% germination, and germination was generally maximized following 80 d CMS. Exogenous potassium nitrate applied as a 5% solution did not stimulate germination, but nearly all seeds (>95%) germinated following treatment with 200, 400, 600, or 800 ppm (w/v) gibberellic acid (GA3) solution. Physical removal of the seed coat or seed exposure to short durations of dry heat did not increase germination. Seed exposure to 1 s of direct flame increased germination, but germination was low relative to germination following CMS and treatment with GA3. Based on these results, we conclude that American burnweed seeds in wild blueberry fields exhibit non–deep physiological dormancy that is most readily broken by CMS and light or seed treatment with GA3. Seeds will likely be exposed to favorable conditions for breaking dormancy (cold temperatures and light) in wild blueberry fields due to lack of tillage and seed burial, indicating high potential for this weed species to proliferate in wild blueberry fields if not properly managed.
Flazasulfuron was evaluated for crop safety and efficacy on hair fescue (Festuca filiformis Pourr... more Flazasulfuron was evaluated for crop safety and efficacy on hair fescue (Festuca filiformis Pourr.) in wild blueberry (Vaccinium angustifolium Ait.) fields. Treatments consisted of flazasulfuron applied at 38 and 50 g a.i. ha−1in fall of the bearing year and spring and fall of the non-bearing year. Industry standard fall bearing year pronamide (2240 g a.i. ha−1) and spring non-bearing year terbacil (2000 g a.i. ha−1) and foramsulfuron (35 g a.i. ha−1) applications were included for comparison. Pronamide consistently reduced flowering hair fescue tuft density in the non-bearing and bearing years across sites. Terbacil reduced flowering tuft inflorescence height in the non-bearing year, but did not reduce total or flowering tuft density in either year. Foramsulfuron reduced flowering tuft density and flowering tuft inflorescence number and height in the non-bearing year, but hair fescue recovered in the bearing year. Fall bearing year flazasulfuron applications did not reduce total or flowering tuft density or flowering tuft inflorescence number and height. In contrast, spring non-bearing year flazasulfuron applications reduced flowering tuft density and flowering tuft inflorescence number and height, though hair fescue recovered in these treatments in the bearing year. Fall non-bearing year flazasulfuron applications reduced hair fescue total tuft density, flowering tuft density, and flowering tuft inflorescence number in the bearing year. No treatments caused significant injury to wild blueberry. Flazasulfuron may contribute to improved hair fescue management in wild blueberry, and this herbicide should be evaluated further to confirm crop tolerance and identify potential use patterns with currently registered herbicides.
A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment... more A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment rate and timing treatments on the growth, yield, berry size and soluble solids of black currants (Ribes nigrum ‘Titania’). Bushes were planted in the spring of 2009 at two sites with black plastic mulch as a weed control without irrigation, and fertilized with seven fertility treatments in either the spring, the summer or split between spring and summer. Rates were 50, 100 and/or 150 kg estimated available N from a blend of crab meal and poultry manure (Nutriwave®). Yield and berry soluble solids were measured in 2010 and 2011. Plants at the site with leaf P and K deficiencies showed lower growth and yield (492-2,540 kg ha-1), but had significant differences in growth response to amendments compared with the site that had adequate levels of P and K, which had no significant difference among treatments in yield in 2011 (3,935-5,016 kg ha-1) or growth among treatments in any of the three years. Where significant differences in growth were found, the medium spring fertility treatment gave the greatest growth and yield, followed by the high spring fertility treatment. The high spring treatment had the highest growth in 2010, but the lowest growth and yield in 2011.
ABSTRACT What is it? The potato crop can be propagated in two ways, vegetatively (clonally) and s... more ABSTRACT What is it? The potato crop can be propagated in two ways, vegetatively (clonally) and sexually (true seeds). Currently, commercial potato production throughout the world is almost completely based on vegetative propagation. True seeds are predominantly used only in breeding work for introduction of new cultivars. Although the potato plant is multiplied using a number of different techniques, in vitro nodal cuttings are probably the most common propagules used in early stages of commercial seed potato production. Since the genetic stability and the production of uniform, true-totype plant material are very important for the industry, the multiplication methods which utilize nodal or apical cuttings and microtubers are preferred in seed potato production. New plants are produced from existing buds assuring identical genetic make-up of the parent plants. In in vitro nodal cutting systems, plantlets are regenerated and multiplied under artificial, aseptic conditions in the laboratory. Depending on the genotype or potato cultivar, 5 to 10 fold multiplication rates per 4 weeks are reported under lab conditions. If virus elimination is needed, cultures are initiated from meristems (dissected portions of the meristematic region of a shoot tip) from plants exposed to a heat treatment or to chemotherapy (i.e. Virozole) prior to culturing. Normally, up to 40% regenerants from meristems are virus-free. Meristems of the treated plants are all disease-free as the pathogens have not been able to enter the less differentiated cells of the meristem. The meristems are then placed on the liquid nutrient media (usually on paper bridges in test tubes) for plant regeneration. They grow into plantlets in approximately 6–8 weeks and then the disease tests are performed on them. Once the disease/virus-free status is determined, the meristem-derived plantlets are used for further rapid multiplication by the in vitro nodal cutting system. The healthy plant material is cut into individual stem portions (single-node
American burnweed is an increasingly common annual weed in wild blueberry fields in Atlantic Cana... more American burnweed is an increasingly common annual weed in wild blueberry fields in Atlantic Canada and Maine. Knowledge of seed dormancy characteristics and potential for this species to form persistent seedbanks in wild blueberry soils, however, is lacking. A series of experiments were therefore conducted to investigate potential mechanisms regulating American burnweed seed dormancy in wild blueberry fields. Seeds were dormant at maturity and did not germinate in dark or light under warm conditions. Cold moist stratification (CMS) at 4 C for 90 d followed by exposure to warm conditions (22/15 C day/night) and light caused >90% germination, and germination was generally maximized following 80 d CMS. Exogenous potassium nitrate applied as a 5% solution did not stimulate germination, but nearly all seeds (>95%) germinated following treatment with 200, 400, 600, or 800 ppm (w/v) gibberellic acid (GA3) solution. Physical removal of the seed coat or seed exposure to short durations of dry heat did not increase germination. Seed exposure to 1 s of direct flame increased germination, but germination was low relative to germination following CMS and treatment with GA3. Based on these results, we conclude that American burnweed seeds in wild blueberry fields exhibit non–deep physiological dormancy that is most readily broken by CMS and light or seed treatment with GA3. Seeds will likely be exposed to favorable conditions for breaking dormancy (cold temperatures and light) in wild blueberry fields due to lack of tillage and seed burial, indicating high potential for this weed species to proliferate in wild blueberry fields if not properly managed.
Flazasulfuron was evaluated for crop safety and efficacy on hair fescue (Festuca filiformis Pourr... more Flazasulfuron was evaluated for crop safety and efficacy on hair fescue (Festuca filiformis Pourr.) in wild blueberry (Vaccinium angustifolium Ait.) fields. Treatments consisted of flazasulfuron applied at 38 and 50 g a.i. ha−1in fall of the bearing year and spring and fall of the non-bearing year. Industry standard fall bearing year pronamide (2240 g a.i. ha−1) and spring non-bearing year terbacil (2000 g a.i. ha−1) and foramsulfuron (35 g a.i. ha−1) applications were included for comparison. Pronamide consistently reduced flowering hair fescue tuft density in the non-bearing and bearing years across sites. Terbacil reduced flowering tuft inflorescence height in the non-bearing year, but did not reduce total or flowering tuft density in either year. Foramsulfuron reduced flowering tuft density and flowering tuft inflorescence number and height in the non-bearing year, but hair fescue recovered in the bearing year. Fall bearing year flazasulfuron applications did not reduce total or flowering tuft density or flowering tuft inflorescence number and height. In contrast, spring non-bearing year flazasulfuron applications reduced flowering tuft density and flowering tuft inflorescence number and height, though hair fescue recovered in these treatments in the bearing year. Fall non-bearing year flazasulfuron applications reduced hair fescue total tuft density, flowering tuft density, and flowering tuft inflorescence number in the bearing year. No treatments caused significant injury to wild blueberry. Flazasulfuron may contribute to improved hair fescue management in wild blueberry, and this herbicide should be evaluated further to confirm crop tolerance and identify potential use patterns with currently registered herbicides.
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