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This study investigated trends in lily (Lilium hybrids) cultivars and challenges for growing cut lily flowers using a survey of producers in the South Korean lily industry. A questionnaire requested information on various topics including the total growing area, length of farming experience, cultivars grown, factors considered when purchasing bulbs, cultivation systems, horticultural practices, disease and pest problems, and horticultural problems. The survey targeted the membership of the Korea Lily Producer Association and the number of respondents corresponded to 43% of all lily farmers in the country. Oriental-Trumpet (OT) hybrid ‘Yelloween’ and Oriental hybrids ‘Siberia’, ‘Medusa’, and ‘Sorbonne’ were mainly cultivated in South Korea. The main flower colors were yellow, white, and pink. Factors considered in choosing cultivars were the prices of bulbs and cut flowers affecting income of the farm. More than 90% of respondents used soil culture in a greenhouse to grow cut flowers. There were various horticultural practices used from planting to harvest. The main pests harming bulb and flower productivity were fungus gnat (Bradysia difformis) and bulb mite (Rhizoglyphus robini), and the most common horticultural problem was leaf scorch. Overall, the survey suggested that the stable production of lily bulb with low cost and high quality was required and practical techniques should be developed for increasing the cut lily production efficiency. In addition, the pests, diseases, and horticultural problems in the given local environmental conditions should be considered when breeding new cultivars and developing production technology.

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The Wisconsin potato crop is managed intensively through multiple inputs of pesticide, fertilizer, and irrigation. Beginning in 1979, a multidisciplinary team at the Univ. of Wisconsin developed an effective Integrated Pest Management Program to address key management decisions associated with this crop. The program fostered the development of several private IPM businesses and continues to help increase the acceptance of IPM technology by the potato industry. Results of component and integrative research, funded by industry, state, and federal sources, provided the essential ingredients for development of computer software now used for managing the potato crop on ≈ 70,000 acres (28,330 ha) of potatoes in a multistate area. The software helps growers determine the need for and timing of critical crop inputs. By reducing or eliminating unneeded pesticide and irrigation applications, the software helps to improve overall production efficiency. Industry adoption of this software is providing the impetus for development of more comprehensive software that includes additional aspects of potato production as well as the production of crops grown in rotation with potato.

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Commercially available novel cultivars of poinsettia, obtained through interspecific hybridization, were subject to colchicine-based mutagenesis to recover their fertility, enabling subsequent breeding. Mutagenic treatment was conducted at different concentrations of colchicine with either lanolin or cotton serving as the matrix. The results indicated that 1 day was the optimal duration of colchicine treatment and that suitable colchicine concentration varied by cultivar. Moreover, one-time treatment gave higher rates of both polyploidy and morphological mutant production than two-times treatment. Specifically, the poinsettia cultivars Dulce Rosa (5 mg·g−1 colchicine with lanolin; 10 mg·mL−1 colchicine with cotton) and Princettia-Hot Pink (15 mg·g−1 colchicine with lanolin; 10 mg·mL−1 colchicine with cotton) yielded relatively high polyploidy production efficiency and morphological mutation rate. Consequently, a total of three polyploidy mutants of ‘Dulce Rosa’ and 19 polyploidy mutants of ‘Princettia-Hot Pink’ were obtained. Both cultivars had mutants with recovered fertility, with pollen germination rate of up to 27.5%. Moreover, unexpected non-polyploidy mutants with various morphological trait variations were also obtained.

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Annual shoot and trunk xylem growth increment of `Starkspur Supreme' in the 1984 NC-140 uniform rootstock trial was studied of 10 selected rootstocks representing a range of tree sizes. Shoot growth was measured weekly from budbreak through harvest in each of four seasons. After 11 seasons of growth, whole trees were cut, placed in water containing diffuse fuschin dye for 30 to 60 min during mid-day. After that, a section of trunk (10 to 15 cm long) was excised at 25 cm above the graft union. Trunk xylem thickness and percent of water transport active xylem were measured. Shoot length during the study was related to both the duration and rate of growth; however, growth duration contributed more to variation among stocks. In all stocks, it appears that almost all xylem translocated water and that there was very little “plugged” or active xylem. There were no differences among stocks for the relative percentage of active xylem. Annual xylem increment width varied with stock. The vegetative growth of these trees will be discussed relative to the production efficiency of scions on these stocks.

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Development of a crop production system that can be used on the International Space Station, long duration transit missions, and a lunar/Mars habitat, is a part of NASA's Advanced Life Support (ALS) research efforts. Selected crops require the capability to be grown under environmental conditions that might be encountered in the open cabin of a space vehicle. It is also likely that the crops will be grown in a mixed-cropping system to increase the production efficiency and variety for the crew's dietary supplementation. Three candidate ALS salad crops, radish (Raphanus sativus L. cv. Cherry Bomb II), lettuce (Lactuca sativa L. cv. Flandria) and bunching onion (Allium fistulosum L. cv. Kinka) were grown hydroponically as either monoculture (control) or mixed-crop within a walk-in growth chamber with baseline environments maintained at 50% relative humidity, 300 μmol·m-2·s-1 PPF and a 16-hour light/8-hour dark photoperiod under cool-white fluorescent lamps. Environmental treatments in separate tests were performed with either 400, 1200, or 4000 μmol·mol-1 CO2 combined with temperature treatments of 25 °C or 28 °C. Weekly time-course harvests were taken over 28 days of growth. Results showed that none of the species experienced negative effects when grown together under mixed-crop conditions compared to monoculture growth conditions.

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Traditional sweet cherry (Prunus avium L.) training systems in the United States are based upon vigorous rootstocks and multiple leader vase canopy architectures. The sweet cherry research lab at Washington State University has been investigating the potential of new rootstocks and training systems to improve production efficiency and produce high quality fruit. This paper describes the effects of three rootstocks—Mazzard (P. avium), `Gisela 6', and `Gisela 5' (P. cerasus × P. canescens)—and four training systems—central leader, multiple-leader bush, palmette, and y-trellis—on `Bing' sweet cherry tree vigor, fruit yield and quality over a seven year period. Compared to trees on Mazzard, trees on `Gisela 5' and `Gisela 6' had 45% and 20% lower trunk cross-sectional areas after 7 seasons, respectively. Trees on `Gisela 6' were the most productive, yielding between 13% and 31% more than those on `Gisela 5' and 657% to 212% more than trees on Mazzard, depending on year. Both Gisela rootstocks significantly improved precocity compared to Mazzard, bearing fruit in year 3 in the orchard. Canopy architecture had only moderate effects on tree vigor and fruit yield. Across rootstocks, bush-trained trees were about 25% less productive compared to the other systems, which exhibited similar cumulative yields (102 kg/tree). Fruit weight was negatively and closely (r 2 = 0.84) related to tree yield efficiency (kg·cm–2). Crop value was related positively to fruit yield.

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One way in which rootstocks may influence production efficiency is by altering the number of spurs, and in particular reproductive spurs. However, rootstock influences on the morpholgy of shoots have not been quantified. Measurements were made on `Starkspur Supreme Delicious' trees growing on 17 rootstocks and planted in 1984 as part of the NC-140 regional rootstock trial. In each of the 6 years from 1988-1993, the length of the 2-year old section of wood of selected branches was measured and the number of spurs, flowers and shoots counted. For all rootstocks, trunk cross-sectional area was closely related to shoot length. Trees on P.22 (the most dwarfing rootstock in the planting) had shoot lengths 40-50% of those of trees on seedling rootstocks. For each rootstock, there was a strong negative relationship between shoot length and spur density, but there was not a common relationship among rootstocks. Similarly, flower number per shoot was also related to shoot length with different relationships for each rootstock. Flower density was not related to vigor for any of the rootstocks.

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Abstract

Research to increase the yield of crop plants is of great long-term importance if we are to continue to meet the food and fiber needs of a rapidly expanding world population. In the short-term, the problem facing agriculture in the United States is not one of production but of profitability. Only improved efficiency and stability of production can ensure the survival of the American farmer in an increasingly competitive world market. The challenge facing agricultural research is to develop new knowledge of basic plant processes and to apply that knowledge toward improved production efficiency. This work must be done in the context of current crop surpluses and reductions in federal spending for such research. In this article, I discuss critical research needs in fields such as horticulture and agronomy in order to meet the challenge of increasing both the productivity and profitability of the producer. This result can be accomplished only by bringing the best technology to bear on the complex problems facing U.S. agriculture.

Open Access

Abstract

Coincident with the world food shortage, ever-increasing food prices and the shortage and high and rising costs of energy, attention is now being directed to the energy-efficiency of agricultural production (1, 5, 6, 12, 13, 18, 30, 31, 34, 40, 45, 47, 48, 52). Although the energy used annually for agriculture in the United States (48) and Canada is not a large percentage of the national totals some feel that to ensure energy supplies “agriculture must stake a claim” (27). The “claim” must stress the form of energy because current agricultural technology is so dependent on liquid fuels for machinery operation and natural gas for the production of nitrogen fertilizers (40). As an important segment of the agricultural industry, horticulturists must also “stake a claim” to energy if they believe fruits and vegetables make a legitimate contribution to food supplies. Fruit and vegetable production is considered energy-extravagant because of the high energy inputs needed compared to the usable energy output (13, 47), although few studies of the energy relationships of individual horticultural crops have been reported. Presented herein are energy calculations for the production of some fruits and vegetables for which production data in Ontario are available with a discussion of the place of fruits and vegetables in a food supply system and the flaws inherent in judging production efficiency solely on an energy basis.

Open Access

Production of passion fruit (Passiflora sp.) via cuttings is a way to eliminate genetic variation in the crop and also results in a faster establishment time. This could aid producers in increasing production efficiency while maintaining genetic lines. The objective of this research was to evaluate ease of rooting and determine the optimal auxin source for seven species of passion fruit. Semihardwood two-node cuttings were taken from the middle of the parent vine, and auxin treatments were applied to the basal end of the cutting. The cuttings were then stuck to a depth of 1 inch on 20 Aug. 2019. Treatments included three auxin sources and seven passion fruit species. Treatments were set up as a randomized complete block design blocking on species, with 10 single-plant replications per treatment. Data were collected 30 d after sticking cuttings and included percent rooted, total root number, average root length (of the three longest roots, measured in centimeters), root quality (0–5 scale, with 0 = dead and 5 = healthy, vigorous root system), root dry weight (measured in grams), and percent callus. Results showed that passion fruit cuttings receiving a hormone treatment had significantly positive effects on rooting responses, such as increased number, length, quality, and dry weight of roots. Blue passionflower (P. caerulea) was the only species in which hormone treatment did not increase rooting compared with the control. The use of hormone to aid in cutting propagation of passion fruit is recommended, depending on the species being propagated.

Open Access