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L. Chercuitte, J.A. SulIivan, Y.D. Desjardins, and R. Bedard

The waiting-bed (WB) system has the potential to significantly increase the length of the strawberry (Fragaria Xananassa Duch.) production season. In the WB phase of this system the plants were deblossomed and runners were removed to stimulate the production of a multiple crowned plant. The objective of this study was to examine the influence of planting date and cultivar on yield potential and vegetative growth of the strawberry plants in the WB and cropping beds (CB). Experiments were conducted in Ontario and Quebec. Early establishment of the WB favored the production of large multicrown plants. `Kent' appeared to be the best cultivar among five tested due to the many berries produced because of good fruit set. Yield potential was not realized in late-planted CB. The highest yields per plant (273 g) were obtained in Quebec with plants from the earliest WB. Yields in CB decreased with later plantings due to stress of transplanting when air and soil temperatures were high. Berry count was identified as the yield component most affected by the later planting date of the CB. The WB system has potential for season extension in strawberry, but WB must be established early in the season to encourage the development of a plant with high yield potential.

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Ricardo Goenaga, Adolfo Quiles, and A. Graves Gillaspie

. Tolerance is defined in this study as the ability of a genotype to produce a good crop even when it is infected with a pathogen ( Agrios, 2005 ). The present study was conducted with the objective of determining yield potential and seed protein of various

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Paige Hanning, Dyremple B. Marsh, and Helen Swartz

The use of cowpea as a forage for Central Missouri has been limited. High mid summer temperatures and frequent drought suggest that an alternative forage for livestock may be advantageous during the hot summer months. The ability of cowpea to withstand drought, high temperature and maintain high foliage protein, justifies research of the forage potential of this crop. Forage yield potential of two cowpea cultivars was evaluated in field experiments in 1968 and 1989, For both years a split plot experimental design was utilized with cowpea cultivar the main plot and harvest date the subplot Dry matter yields for both cultivars were similar at the early harvest dates. However, both fresh and dry shoot yields of Vita 3 (V3) were significantly higher than that of California Blackeye #5 (CB #5) at the later harvest stages. CB #5 plants produced a significantly higher stem dry weight while V3 produced higher leaf dry matter. Foliage regrowth after clipping was substantial for both cowpea cultivars. However, V3 produced 30% higher growth than CB #5. In vitro dry matter digestibility (IVDDM) varied with sample date (plant age) and plant parts sampled. IVDDM was 77% for leaves and 60% for stems of CB#5, and 80% for leaves and 65% for stems of V3.

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Justine E. Vanden Heuvel, John T.A. Proctor, and J. Alan Sullivan

Trellising and cane density treatments were applied to vigorous raspberry (Rubus idaeus L.) cv. Titan plants in Southern Ontario to determine their effects on yield, yield potential, and canopy microclimate during the 1997 and 1998 seasons. The trellising treatments compared were hedgerow (control), V-trellis, and single-sided shift-trellis (shift-trellis). Cane densities (9, 16, 23, and 30 canes/m2) were established before budbreak each season. The treatments significantly affected yield and yield components. Path analysis indicated that interrelationships among yield components were significantly affected by trellising system. In the second season, plants trained on the V-trellis yielded more than did those in a hedgerow system, while those trained on a shift-trellis had the lowest yield because of a smaller fruiting framework. Fruit quality was lower on the shifttrellis than in the other two systems. These differences were related to light penetration into the three canopies. While an optimum cane density was not found for any system, the maximum cane density (30 canes/m2) produced the highest yields. Yield potential per cane decreased as cane density increased; however, the increase in cane number compensated for this decrease, resulting in an increase in total yield per unit area. Fruit quality also decreased as cane density increased, but cane density did not affect canopy microclimate.

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Neil O. Anderson and Peter D. Ascher

Commercial chrysanthemums are short day (SD) plants. Recently, several day neutral (DN) garden genotypes have been identified. Both glasshouse and garden cultivars vary in heat delay insensitivity (HDI). This research analyzed yield components (seed set, germination, yield potential) and tested a DN/HDI ideotype for its effectiveness. Progeny from a 6 × 6 diallel were embryo rescued, clonal ramats were grown in two environments (glasshouse—long days; field—long to short days) and evaluated for flowering, early flowering response groups, thermozero temperature response, low long day leaf number (LDLN), high leaf initiation rates, and low mean stem lengths of the terminal shoot. Self seed set ranged from 0% to 8% while outcross seed set was 0% to 92%. General and specific combining ability were highly significant for seed set, the reciprocals, and their interactions. Germination averaged 67%, while yield potential was 44%. Cotyledon pigmentation in embryo rescued seedlings was 7% albinos, 15% anthocyanin (transposable elements), and 78% normal (green). SD parents did not flower in either photoperiod although PPSL-10 carried alleles for DN. SD x DN crosses produced some DN progeny and fit a 1:3 chi square ratio (DN:SD), indicating DN to be recessive. However, DN x DN crosses also fit a 3:1 chi square ratio, due to HDI. No progeny flowered within the 3 to 6 week ideotype; visible bud date had a heritability of h 2 = 0.50. Most progeny were within the LDLN range (h 2 = 0.72). Several leaf initiation rates exceeded the ideotype (h 2 = 0.003); plant height also matched the ideotype (h 2 = 0.66). Both visible bud and flowering dates require significant improvement before progeny match the DN/HDI ideotype.

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Kathryn M. Kleitz, Marisa M. Wall, Constance L. Falk, Charles A. Martin, Marta D. Remmenga, and Steven J. Guldan

Field studies were conducted in 1995 and 1996 at Las Cruces, New Mexico, and Alcalde, New Mexico, to compare direct seeding to transplanting for stand establishment and yield estimates of calendula (Calendula officinalis), catnip (Nepeta cataria), lemon balm (Melissa officinalis), stinging nettle (Urtica dioica), and globemallow (Sphaeralcea spp.). Calendula established well from seed or transplants at both sites. Transplanting increased establishment of lemon balm, catnip, stinging nettle, and globemallow. Lemon balm establishment was increased by 230% to 400% at Las Cruces, and catnip establishment was increased by 84% to 100% at Alcalde by transplanting. Direct seeding resulted in little or no stand establishment for stinging nettle and globemallow at Alcalde. In 1996, transplants increased lemon balm and stinging nettle dry weight yields by a factor of three or more at both sites. Dry weight yields of transplanted catnip were 4.86 t·ha−1 in 1995 and 7.90 t·ha−1 in 1996 in Las Cruces. Alcalde yields for transplanted dried catnip were 2.43 t·ha−1 in 1995 and 5.12 t·ha−1 in 1996. Transplanted globemallow dry weight yields were 6.04 t·ha−1 in 1995 and 9.17 t·ha−1 in 1996 for Las Cruces. Transplanted stinging nettle yield in Alcalde was 5.91 t·ha−1 for plants that overwintered and were harvested in the second season. Transplanting versus direct seeding medicinal herbs has the potential to substantially increase stand establishment and yield in New Mexico, particularly in the more northern and cooler part of the state.

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Kathryn M. Kleitz, Marisa M. Wall, Constance L. Falk, Charles A. Martin, Steven J. Guldan, and Marta D. Remmenga

Field studies were conducted to determine the production potential of echinacea (Echinacea purpurea), valerian (Valeriana officinalis), mullein (Verbascum thapsus) and yerba mansa (Anemopsis californica) medicinal herbs at two sites in New Mexico. Las Cruces, N.M., is at an elevation of 3,891 ft (1,186 m) and has an average of 220 frost free days per year, whereas Alcalde, N.M., is at an elevation of 5,719 ft (1,743 m) and averages 152 frost-free days per year. In-row plant spacings of 12, 18 and 24 inches (30.5, 45.7, and 61.0 cm) were compared at both locations. The corresponding plant densities for the 12, 18 and 24 inch spacings were 14,520 plants/acre (35,878 plants/ha), 9,680 plants/acre (23,919 plants/ha), and 7,260 plants/acre (17,939 plants/ha), respectively. Data were collected on growth rates, fresh yield, and dry yield for the herbs grown at each site. All crops at both sites had highest plot yields at the 12-inch spacing, suggesting that optimum in-row plant spacings are at or below the 12-inch spacing. Yields of 1.94 ton/acre (4.349 t·ha-1) of dried yerba mansa root, 0.99 ton/acre (2.219 t·ha-1) of dried echinacea root, and 2.30 ton/acre (5.156 t·ha-1) of dried mullein leaves were realized at the 12-inch spacing at Las Cruces in southern New Mexico. Yields of 1.16 ton/acre (2.600 t·ha-1) of dried valerian root, 0.93 ton/acre (2.085 t·ha-1) of dried echinacea root, and 0.51 ton/acre (1.143 t·ha-1) of dried mullein leaves were harvested at the 12-inch spacing at Alcalde in northern New Mexico. Yields of fresh echinacea flowers were 1.56 ton/acre (3.497 t·ha-1) in Las Cruces. Yields of dried mullein flowers were 0.68 ton/acre (1.524 t·ha-1) in Las Cruces and 0.66 ton/acre (1.479 t·ha-1) in Alcalde.

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S. Perez-Gonzalez

The garambullo is a native cactus that grows wild in the semiarid region of central and northeastern Mexico. It is highly appreciated by local people for the quality of its fruits and as a pigment source for the food industry. However, there is no information available about its real production potential. The main objective of this work is to collect field data about tree density, phenology, and yield components of natural stands. Six plots (2000 m2 each) were randomly selected where garambullo grows wild in southwestern Querétaro and the following data was collected: number and distance among trees, age distribution, blossom and harvest season, fruit weight and number/tree, fruit/areole, areoles/fruiting arm, arms/branch and branches per tree. Tree density and yield varied greatly among plots and trees, from less than 20 to 237 trees/ha, and from less than 100 to 10,000 fruits/tree. Average fruit weight was 0.97 g and mean yield/tree was 2.79 kg. Possibilities for increasing yield efficiency will be discussed.

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Michael W. Smith

, the bearing surface receiving adequate sunlight could be reduced to 1 ha·ha −1 , substantially reducing orchard yield potential. Canopy volume was relatively low when trees were small (25 ML·ha −1 canopy volume with 0.02-m 2 cross-sectional trunk

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Harbans L. Bhardwaj and Anwar A. Hamama

Even though mothbean (Vigna aconitifolia), a drought- and heat-tolerant crop, may have potential in the eastern United States, information about its production in this region is not available. To characterize potential seed yields and preliminary nutritional quality, 54 accessions were grown near Petersburg, VA, during 2011, 2012, and 2013. The seed yields varied from 48 to 413 lb/acre. The mean concentrations of protein, calcium, iron, and zinc in mature mothbean seed were 21.9%, 0.17%, 64.8 ppm, and 37.5 ppm, respectively. These values compared well with those in mungbean (Vigna radiata) and tepary bean (Phaseolus acutifolius). The results demonstrated that mothbean has considerable potential as an alternative, new food legume crop in Virginia and eastern United States.