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- Author or Editor: Joan R. Davenport x
To examine the impact of N fertilizer rates and timing on cranberry (Vaccinium macrocarpon Ait.) yield and the fruit quality factors total anthocyanin, average berry weight, and field and storage rot, plots were established for 3 to 4 years. The cranberries received a total of 0, 22, or 44 kg N/ha over the growing season applied in three, four, or five applications, which varied by growth stage. There were eleven possible treatment combinations in Massachusetts on `Early Black' and `Howes' and in Wisconsin on `Stevens' and `Searles', and seven possible treatments in New Jersey on `Early Black' and in Washington on `McFarlin'. The results showed a nationwide response to N that suggests the experimental middle rate of 22 kg·ha-1 would result in high yields with moderate rot. However, the best timing for applying the fertilizer varied by both state and cultivar, where three late season applications were best on `Early Black' in New Jersey versus four early season applications on the same cultivar in Massachusetts, and applying N fertilizers across five applications was optimal for `Stevens' in Wisconsin.
Potato (Solanum tuberosum L.) is grown extensively throughout the Pacific Northwest as a high-value crop in irrigated rotations with other row crops such as wheat (Triticum aestivum L.) and corn (Zea mays L.)—both field and sweet. Center pivots are predominant irrigation systems. Soil texture ranges from coarse sands to finer textured silt loams and silts and can vary within one field, often with very hilly topography. Site-specific management is being evaluated as an approach to help to optimize inputs (water, seed, agricultural chemicals) to maintain or enhance yield and reduce the potential of negative environmental impacts in these farming systems. Currently variable rate fertilizer application technology and harvest yield monitoring equipment are commercially available for these systems. Variable rate seeding and variable rate irrigation water application technologies are developed but not fully commercialized and variable rate pesticide application equipment is in development. At the Irrigated Agr. Res. and Ext. Ctr. in Prosser, Wash., we have a team of research scientists (both university and USDA/ARS), interested individuals from local industry, and other key organizations (e.g., local conservation districts) who are working together to evaluate different site specific technologies, improve the ability to use available tools, and to improve decision-making ability by conducting research both on farm and in research plots.
Leaf yellowing (chlorosis) is not unique to Concord grape, yet occurs with great intensity in the arid, irrigated central Washington state growing region. Past research on nutrients has not shown a clear cause and effect relationship between soil and/or plant nutrient status and chlorosis. We investigated both nutritional and climatic conditions for their association with chlorosis occurrence. Six vineyard sites were selected, 2 each with no history of chlorosis (achlorotic), occasional chlorosis, and annually reoccuring chlorosis (chronically chlorotic) and monitoring sites in chlorotic and achlorotic areas were established. Nutrient elements K, Ca, Mg, Mn, and Cu plus the nonnutrient elements Na and Al were monitored in soil (surface, 0 to 30 cm, and subsurface, 30 to 75 cm, depths) and leaf tissue (both petioles and blades) prebud burst (soil only), at bloom, and preveraison at 650 degree days at all vineyard sites for the 2001, 2002, 2003, and 2004 growing seasons. In addition, both soil temperature and moisture were monitored. To evaluate the intensity of chlorosis at each site, chlorotic vines were GPS marked and mapped post-bloom each year. Overall, chlorosis incidence was more widespread in 2001 and 2003 than in 2002 or 2004. There were few relationships with soil or tissue nutrient concentrations. However, soil moisture was consistently higher and soil temperature lower in the period between bud burst and bloom in the chlorotic sites. This suggests that a cold, wet soil environment prior to bloom impedes grape root growth and/or function and triggers plant chlorosis. Yearly differences strongly support this finding.
Potatoes (Solanum tuberosum L.) are grown extensively throughout the Pacific northwestern United States as a high value crop in irrigated rotations with other row crops such as wheat (Triticum aestivum L.) and both field and sweet corn (Zea mays L.). Center pivots are the predominant irrigation systems. Soil texture ranges from coarse sands to finer textured silt loams and silts and can vary within one field, particularly in fields with hilly topography. Site specific management is being evaluated as an approach to help to optimize inputs (water, seed, agricultural chemicals) to maintain or enhance yield and reduce potential negative environmental impacts from these farming systems. Currently, variable rate fertilizer application technology and harvest yield monitoring equipment are commercially available for potato. Variable rate seeding and variable rate irrigation water application technologies are developed but not fully commercialized and variable rate pesticide application equipment is in development. At the Irrigated Agricultural Research and Extension Center in Prosser, Wash., we have a team of research scientists, interested individuals from local industry, and other key organizations (e.g. local conservation districts) who are working together to evaluate different site specific technologies, improve the ability to use available tools, and to improve decision-making ability by conducting research both on farm and in research plots.
Understanding how grape (Vitis L.) vines store nutrients in permanent tissues, how much nutrient vines take up from the soil, and how nutrients are partitioned and redistributed throughout the plant is critical to the development of sound nutrient management practices. This study investigated the seasonal patterns of macronutrient uptake and redistribution in whole ‘Concord’ grape (Vitis labruscana Bailey) vines. The study was conducted in a 42-year-old own-rooted ‘Concord’ vineyard. The site was a furrow-irrigated fine sandy loam. In 2006 and 2007, four vines were excavated at winter pruning, budbreak, three- to four-leaf stage, bloom, veraison, harvest, and postharvest. Each vine was separated into different organs, dried, and weighed to determine biomass, and then ground and analyzed for C, N, P, K, Ca, and Mg. The results showed that the seasonal dynamics of nutrient contents shared a consistent pattern: translocation of nutrients from woody tissues to actively growing organs at the beginning of the season; nutrient uptake from bloom to veraison (P and Mg in 2006), bloom to harvest (N, P, K, and Ca), or veraison to harvest (P and Mg in 2007); and nutrient movement to woody tissues occurring after veraison until leaf fall with no further nutrient uptake. There was a very high accumulation of Ca in permanent structures of the vine, reflecting the high Ca and CaCO3 found in the soils of the region. As a result, the vines had a higher Ca content than all other nutrients throughout the growing season, which is different from findings in other growing areas.
This study investigated the distribution of the micronutrients boron (B), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in 42-year-old ‘Concord’ grapevines (Vitis labruscana Bailey) grown in a calcareous soil to understand seasonal partitioning and distribution of micronutrients throughout various grapevine tissues. In 2006 and 2007, four vines each were excavated at winter pruning, budbreak, the three- to four-leaf stage, bloom, veraison, harvest, and postharvest. Separated plant organs were measured for biomass and analyzed for B, Fe, Mn, Cu, and Zn. The results showed that seasonal patterns of micronutrient concentrations varied considerably with respect to organ and growth stage. Leaf blades, shoot tips, and petioles had the highest concentration of B at bloom and Mn at harvest, whereas Fe, Cu, and Zn concentrations were highest in fine roots but values varied over time each year. Whereas seasonal patterns of Fe, Cu, and Zn contents differed year by year, B and Mn contents had a similar pattern over both years. Translocation of B and Mn from woody tissue to actively growing organs occurred at the beginning of the season. The majority of B uptake occurred between bloom and veraison, whereas that of Mn occurred between bloom and harvest. There were similar B concentrations in shoot tips and leaf blades. Boron remobilization to woody tissues from the leaves occurred between veraison and harvest, suggesting moderate, late-season, phloem mobility of B in ‘Concord’ grapevines. Microsite differences in soil pH likely contribute to variable nutrient availability around the root system, demonstrated by high variability of Fe, Cu, and Zn contents in different vine organs.
Cranberry (Vaccinium macrocarpon Ait.) has the opportunity to partition resources into sexual and/or asexual (stolons) modes of reproduction. Nitrogen status has been shown to impact the degree of stoloniferous growth. To determine whether there is a genotypic response to varying nitrogen levels, six hybrid and four native cultivars were treated with three annual rates of nitrogen fertilizer (17, 34, or 67 kg·ha-1) for 4 years. Fruit yield was determined each year and asexual vegetative growth (stolons) weight was removed and measured in all but the first year of the experiment. Cultivars exhibited different patterns of yield and stolon weight response over the three nitrogen rates. Not all cultivars exhibited significant yield decreases at the high N levels. Vegetative growth (stolon weight) generally increased with increasing N, however, not all cultivars responded similarly over three N rates. Partitioning between yield and stolon production favored fruit yield at the lower N rates in three of the four native cultivars studied (`Cropper', `Early Black', and `Howes'). Yield over N rates was more stable for four of the six hybrid cultivars, which may be the result of greater heterozygosity in hybrids than natives, and/or genetic gain from one breeding and selection cycle, offering increased tolerance to nitrogen stress. This study indicates that genetic variation exists for yield, yield stability, and stolon production relative to nitrogen level, and that genetic gain in cranberry is possible for these traits. Future studies involving cranberry physiology and nutrition should consider the genotypes used.
It has been speculated that cranberries are susceptible to chloride injury. If this is the case, it is possible that applications of high rates of 0-0-60 (KCl) fertilizer as a K source could be detrimental to cranberry productivity. Grower anecdotes of using 0-0-60 to “shut down the plants” persist. Supposedly, using 225+ kg·ha-1 of this material slows or arrests vegetative growth. In fact, growers have claimed it can overcome the production of rank vegetation that results when too much N fertilizer has been applied. Field plots were initiated to determine the suitability of KCl and to determine if high K rates could overcome the deleterious effects of excess applied N. Plots were set up in a split-block plot design with N doses [three each “normal” (28-34 kg·ha-1 N) vs. “high” (56-67 lb N/A)] in one direction and potassium/chloride treatments in the other direction (KCl or K2SO4 at 115 or 225 kg K2O; CaCl2 to give the equivalent Cl as in the high-rate KCl treatment, and a nontreated control) for a total of 36 2 × 2-m plots per each of three cultivar locations. Plots were treated and evaluated for three consecutive years. There were no significant differences in yield among the K2SO4 and KCl treatments, indicating that at rates as high as 225 kg·ha-1 K2O, 0-0-60 and 0-0-50 perform similarly. Further, treatment with CaCl2 had no significant effect on yield. In the third year, plots receiving no K treatment had significantly lower yield than those receiving either rate or form of K (single degree of freedom comparison, significant at 0.03). These results indicate that at the rates used in this study, KCl is an adequate K source. The effect of N rate was more pronounced than that of the K treatments. In years two and three, the low N rate strips had significantly greater yield compared to that in the high N rate strips. By year two, the high N strips were visually different, with rank overgrowth. There was no significant interaction of N rate and the K treatments. While there was a trend for greater difference between the 0 K and 115 kg K rates in the high N plots compared to the moderate N plots, the addition of K never entirely overcame the negative yield effects of high N rate.
Surface sand application to cranberry (Vaccinium macrocarpon Ait.) is commonly practiced for a combination of vine and insect management. However, the efficacy of sanding on crop production has been poorly documented. This study determined the effect of three rates of sand application using a barge sanding technique on two different cultivars—`Early Black' and `Stevens'. Beds were sanded to a depth of 0, 1.3, or 2.5 cm in November and monitored at the end of the following three growing seasons for yield, berry weight, and upright distribution. The 2.5-cm sanding rate adversely affected yield in `Early Black' during the first two growing seasons. In `Stevens' yields were not reduced until the third season and then only by the 2.5-cm rate. Although the 2.5-cm sanding rate increased vegetative upright density in both cultivars in the first growing season, yield and number of fruiting uprights were not significantly influenced the next year. Application of 1.3 cm of sand could improve insect pest management without negatively impacting yields of `Early Black' and `Stevens'.