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Clonal selection of European winegrapes (Vitis vinifera) allows the exploitation of an important source of genetic diversity. In the 1980s, many `Pinot noir' clones, previously unavailable in the U.S., were imported from France. To provide information on their performance under Oregon soil and climate conditions, 20 `Pinot noir' clones were established in a replicated trial in Alpine, Ore., planted in 1989. In this study, yield components, pruning weight, and juice composition of the 20 clones were measured for the 1995 through 1999 seasons. Skin anthocyanin concentration was measured for the 1996 through 1999 seasons. Clones included in the trial were Colmar (COL) 538, Dijon (DJN) 10/18, DJN 113, DJN 114, DJN 115, DJN 375, DJN 60, Espiguette (ESP) 236, ESP 374, Foundation Plant Services (FPS) 2A, FPS 4, FPS 10, FPS 16, FPS 17, FPS 22, FPS 23, FPS 29, FPS 31, FPS 32, and FPS 33. For all responses except juice pH and skin anthocyanin concentration, there were significant clone by year interactions. COL 538 had the highest 5-year mean yield (2.93 kg/vine); FPS 29 had the lowest (1.21 kg/vine). DJN 10/18, FPS 4, FPS 22, and FPS 31 were among the five highest-yielding clones. Other low-yielding clones included DJN 115, ESP 374, FPS 17, and FPS 23. Pruning weights were generally correlated with yields. COL 538 had the highest 5-year mean pruning weight (0.81 kg/vine) and FPS 17 had the lowest (0.48 kg/vine). Other clones with relatively high pruning weights were FPS 2A, FPS 4, and FPS 22. Other clones with low pruning weights were FPS 23 and FPS 29. FPS 22 and FPS 17 had the highest (1.13 g/berry) and lowest (0.93 g/berry) 5-year mean berry weights, respectively. Clones with 5-year mean cluster weights >100 g included DJN 10/18, ESP 236, and FPS 31. Those with cluster weights <80 g were DJN 115, FPS 17, and FPS 29. FPS 2A had the highest 5-year mean juice soluble solids concentration (SSC) at harvest (23.8%). FPS 10, FPS 29, DJN 113, and DJN 115 also had relatively high SSC. DJN 60 had the lowest 5-year mean SSC at harvest (22.0%). FPS 22, FPS 33, COL 538, and ESP 374 also had relatively low 5-year mean SSC at harvest. DJN 115 had the highest 5-year mean juice pH (3.15). DJN 113, FPS 29, and FPS 10 also had relatively high juice pH. FPS 22 had the lowest 5-year mean juice pH at harvest (2.97), and DJN 10/18, FPS 2A, and FPS 17 also had relatively low pH. Clones with higher SSC and pH generally had lower titratable acidity. FPS 2A had both high SSC and high titratable acidity. FPS 23 and FPS 17 had the highest skin anthocyanin concentration (2.10 and 2.07 mg·g-1 berry, respectively). The range of skin anthocyanin concentration among the other clones was relatively narrow (1.17-1.47 mg·g-1 berry). FPS 2A, FPS 4, and FPS 10 generally had above mean SSC and yield. FPS 29, DJN 113, DJN 114, and DJN 115 consistently had above mean SSC but below mean yield.
Germination trials of three seedlots were conducted over a temperature gradient for 14 days to determine the optimal germination temperature for the Black-eyed Susan (Rudbeckia fulgida Ait.). The optimal germination temperature for R. fulgida seeds was 30 ± 1C. All three seedlots began germination (radicle emergence) on the second day at 30.2C. By day four, all seedlots sur-passed 50% germination, with three seedlots germinating 53%, 52%, and 73%. Mean germination percentages were higher between 28.3 and 32.6C than at temperatures above or below this range. Significantly higher germination percentages and enhanced germination rates attained at the elevated temperatures may save time, cut production costs, and decrease exposure to detrimental pre-emergent pathogenic fungi.
Carfentrazone is a broadleaf weed control herbicide that is also used for control of silvery-thread moss (Bryum argenteum) in creeping bentgrass (Agrostis stolonifera) putting greens. Field studies were initiated in June 2006 and May 2007 to evaluate silvery-thread moss control with carfentrazone alone, carfentrazone applied with nitrogen (N) and/or topdressing (TD), N alone, TD alone, and mancozeb plus copper hydroxide. All treatments except for mancozeb plus copper hydroxide and the non-treated control reduced silvery-thread moss populations 16 weeks after initial treatment. Carfentrazone applied alone and carfentrazone followed by N decreased silvery-thread moss populations by 39%. Carfentrazone followed by TD and carfentrazone followed by N + TD decreased silvery-thread moss populations by 73% and 66%, respectively. These data indicate the importance of using cultural practices to control silvery-thread moss on creeping bentgrass putting greens.
Over-fertilization (i.e., the application of fertilizer nitrogen (N) in excess of the tree or vine capacity to use it for optimum productivity) is associated with high levels of residual nitrate in the soil, which potentially contribute to groundwater and atmospheric pollution as a result of leaching, denitrification, etc. Overfert-ilization also may adversely affect productivity and fruit quality because of both direct (i.e., N) and indirect (i.e., shading) effects on flowering, fruit set, and fruit growth resulting from vegetative vigor. Pathological and physiological disorders as well as susceptibility to disease and insect pests also are influenced by the rate of applied N. Over-fertilization appears to be more serious in orchard crops than in many other crop species. The perennial growth habit of deciduous trees and vines is associated with an increased likelihood of fertilizer N application (and losses) during the dormant period. The large woody biomass increases the difficulty in assessing the kinetics and magnitude of annual N requirement. In mature trees, the N content of the harvested fruit appears to represent a large percentage of annual N uptake. Overfertilization is supported by a) the lack of integration of fertilizer and irrigation management, b) failure to consider nonfertilizer sources of plant-available N in the accounting of fertilizer needs, c) failure to conduct annual diagnosis of the N status, and d) the insensitivity of leaf analysis to over-fertilization. The diversity of orchard sites (with climatic, soil type, and management variables) precludes the general applicability of specific fertilization recommendations. The lack of regulatory and economic penalties encourage excessive application of fertilizer N, and it appears unlikely that the majority of growers will embrace recommended fertilizer management strategies voluntarily.
Sixteen cultivars of green bell peppers (Capsicum annuum) were evaluated on the basis of yield in three locations across Pennsylvania during the growing seasons of 2008–09. Cultivars were evaluated in comparison with the cultivar Paladin. In central Pennsylvania, all the cultivars trialed had marketable yields (based on weight) not different than ‘Paladin’ except ‘Lynx’, ‘Socrates’, and ‘Escape’. In terms of fruit number, all cultivars were not different than ‘Paladin’ except ‘Socrates’. For large-sized fruit, all the cultivars trialed are recommended. In southeastern Pennsylvania, all the cultivars trialed except SP-05–47 had marketable yields not different than ‘Paladin’. For large-sized fruit, ‘Revolution’ outperformed all other cultivars, including ‘Paladin’. In southwestern Pennsylvania, all the cultivars trialed except Lynx and SP-05–47 produced comparable marketable yields to ‘Paladin’. None of the cultivars evaluated, including Paladin, consistently outperformed Revolution in terms of large fruit. Statewide, all the cultivars, except Lynx and SP-05–47, are recommended on the basis of marketable yields. For growers looking for large-sized fruit to meet market demand the cultivar Revolution is recommended over ‘Paladin’.
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.
Cost and return estimates are presented for selected medicinal herbs grown in a plant-spacing study at two sites in New Mexico. The selected herbs were echinacea [Echinacea purpurea (L.) Moench], valerian (Valeriana officinalis L.), and yerba mansa (Anemopsis californica Nutt.). Significant returns to land and risk were observed in the crops grown at the closest plant spacing, 12 inches (30 cm). Return to land and risk after two growing seasons from echinacea was estimated for a 10-acre (4-ha) farm to be $16,093/acre ($39,750/ha) in Las Cruces and $14,612/acre ($36,092/ha) in Alcalde.
To provide growers with regional and statewide recommendations, 23 cultivars of bicolor and white synergistic sweet corn (Zea mays) were evaluated in southwestern, central, and southeastern Pennsylvania. ‘Temptation’ was the standard. Despite differing production practices used in all locations, all cultivars were not different or produced more marketable primary ears compared with Temptation. Paydirt was the only cultivar to produce lower marketable yields by weight than Temptation in 2 site years or more. However, ‘Paydirt’ has an early maturity, which improves its acceptability. Very few ears were unmarketable. In terms of ear size, measured as diameter and length, overall all cultivars were not different from Temptation. ‘Temptation’ is early maturing and ear size was expected to be smaller than later maturing cultivars. This was not observed. Ease of hand harvesting was determined by measuring two factors: distance from the base of the primary ear to the soil line and ease of picking (1–5 rating scale where 1 = difficult and 5 = easy). The closer the primary ear was to the soil line was thought to be more difficult to harvest. ‘Synergy’, ‘Espresso’, ‘Kristine’, and ‘Paydirt’ ears were lower than ‘Temptation’ on the culm in 2 site years or more. ‘Whiteout’, ‘Synergy’, and ‘Mattapoisett’ were rated as more difficult to pick than ‘Temptation’ in 2 site years or more. Distance from the soil line to the primary ear and picking ease ratings were not observed to be closely related to each other and a combination of these and other factors may more accurately reflect the ease of hand harvesting. Overall, growers in our region have access to a lot of synergistic sweet corn cultivars with acceptable yield, quality, and ease of hand harvesting characteristics giving them a wide range of options.
Field studies were conducted in three Florida locations (Bradenton, Gainesville, and Quincy) during 1998-99 and 1999-2000 to: 1) compare the performance of two transplant systems under diverse MBr alternative programs in `Chandler' strawberry (Fragaria ×ananassa), and 2) determine the efficacy of these treatments on soilborne pest control in strawberry. Fumigant treatments were: 1) nonfumigated control, 2) methyl bromide plus chloropicrin (MBr + Pic) at a rate of 350 lb/acre, 3) Pic at 300 lb/acre and napropamide at 4 lb/acre, 4) 1,3-dichloropropene (1,3-D) plus Pic at 35 gal/acre and napropamide at 4 lb/acre, 5) metam sodium (MNa) at 60 gal/acre and napropamide at 4 lb/acre, and 6) MNa followed by 1,3-D at 60 and 12 gal/acre and napropamide at 4 lb/acre, respectively. Strawberry transplants were either bare-root or containerized plugs. There were no significant fumigant by transplant type interactions for strawberry plant vigor and root weight per plant, whereas ring nematode (Criconema spp.) and nutsedge (Cyperus rotundus and C. esculentus) populations, and total marketable fruit weight were only infl uenced by fumigant application. The nonfumigated plots had the lowest strawberry plant vigor and root weight per plant in all three locations. In most cases, plant vigor and root biomass per plant increased as a response to any fumigant application. With regard to the transplant type, bare-root transplants had similar plant vigor as plugs in two of the three locations. Fumigation improved nutsedge and ring nematode control. All fumigants had higher early and total marketable yield than the nonfumigated control, whereas transplant type had no effect on total fruit weight.
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.