scholarly journals Evaluating Phosphorous Fertilization and Commercial Biostimulants for Producing Cabbage

1995 ◽  
Vol 5 (4) ◽  
pp. 298-300 ◽  
Author(s):  
Joseph R. Heckman
Keyword(s):  
Brassica Oleracea ◽  
Plant Tissue ◽  
Soil Test ◽  
Nutrient Analysis ◽  
P Fertilizer ◽  
Soil Test P ◽  
Yield Responses ◽  
Very High

Yield responses of `Blue Vantage' cabbage (Brassica oleracea L.) to P fertilizer and two commercially available biostimulants—ROOTS and ESSENTIAL-were evaluated on soils very high in P fertility. Head yield was not increased with P fertilizer when cabbage was transplanted into soil with Mehlich-3 soil test P indexes ≥ 112 ppm (112 mg·kg-1). Neither of the biostimlants applied as a root drench at transplanting influenced head yield or plant tissue nutrient analysis.

scholarly journals Managing Phosphorus for Citrus Yield and Fruit Quality in Developing Orchards

HortScience ◽  
2008 ◽  
Vol 43 (7) ◽  
pp. 2162-2166 ◽  
Author(s):  
Thomas A. Obreza ◽  
Robert E. Rouse ◽  
Kelly T. Morgan
Keyword(s):  
Fruit Quality ◽  
Fruit Production ◽  
Soil Test ◽  
Citrus Paradisi ◽  
Soil P ◽  
Volume Yield ◽  
Canopy Volume ◽  
P Fertilizer ◽  
Soil Test P ◽  
Very High

No calibrated phosphorus (P) soil test exists to guide Florida citrus fertilization. Applying P fertilizer to citrus when it is not needed is wasteful and may cause undesirable P enrichment of adjacent surface water. The objective of this study was to establish guidelines for P management in developing Florida grapefruit (Citrus paradisi Macf.) and orange (Citrus sinensis L. Osb.) orchards by determining the effect of P fertilizer rate on soil test P and subsequently calibrating a P soil test for citrus yield and fresh fruit quality. Two orchards were planted on sandy soil with 3 mg·kg−1 (very low) Mehlich 1 soil test P. In Years 1 through 3, P fertilization increased soil test P up to 102 mg·kg−1 (very high). In Years 4 through 7, canopy volume, yield, and fruit quality did not respond to available soil P as indexed by soil testing. As tree size and fruit production increased, leaf P was below optimum where soil test P was below 13 mg·kg−1 (grapefruit) or 31 mg·kg−1 (oranges). Total P in the native soil at planting was ≈42 mg·kg−1, which was apparently available enough to support maximum tree growth, fruit yield, and fruit quality for the first 7 years after planting. Trees were highly efficient in taking up P from a soil considered very low in available P. Citrus producers can likely refrain from applying P fertilizer to young trees on Florida sandy soils if soil test P is very high or high and probably medium as well.

EFFECTS OF NITROGEN, PHOSPHORUS, POTASSIUM, AND MANURE FACTORIALLY APPLIED TO POTATOES IN A LONG-TERM STUDY

1973 ◽  
Vol 53 (2) ◽  
pp. 205-211 ◽  
Author(s):  
W. N. BLACK ◽  
R. P. WHITE
Keyword(s):  
Solanum Tuberosum L ◽  
Starch Content ◽  
Leaf Tissue ◽  
Soil Test ◽  
Term Study ◽  
Long Term Study ◽  
Soil Test P ◽  
Yield Responses ◽  
Nitrogen Phosphorus

The effects of N, P, K, and manure factorially applied to potato (Solanum tuberosum L.) yields, starch content, and soil and tissue nutrient levels were evaluated on continuous plots over 12 yr in a 4-yr potato, grain, hay, hay rotation. Although yield responses were observed with N, P, and K applications, manure application substantially increased yields above yield levels due to applied N, P, and K. Increasing rates of KCl strongly depressed tuber starch contents. Soil test P and K levels increased with repeated fertility applications, and leaf tissue levels were increased with N, P, and K treatments.

Relationship of soil phosphorus fractions to phosphorus soil tests and fertilizer response

2003 ◽  
Vol 83 (4) ◽  
pp. 443-449 ◽  
Author(s):  
R. H. McKenzie ◽  
E. Bremer
Keyword(s):  
Available P ◽  
Soil Test ◽  
Strongly Correlated ◽  
P Fractions ◽  
Soil Tests ◽  
Fertilizer Response ◽  
Inorganic P ◽  
Soil P ◽  
P Fertilizer ◽  
Soil Test P

Soil tests for available P may not be accurate because they do not measure the appropriate P fraction in soil. A sequential extraction technique (modified Hedley method) was used to determine if soil test P methods were accurately assessing available pools and if predictions of fertilizer response could be improved by the inclusion of other soil P fractions. A total of 145 soils were analyzed from field P fertilizer experiments conducted across Alberta from 1991 to 1993. Inorganic P (Pi) removed by extraction with an anion-exchange resin (resin P) was highly correlated with the Olsen and Kelowna-type soil test P methods and had a similar relationship with P fertilizer response. No appreciable improvement in the fit of available P with P fertilizer response was achieved by including any of the less available P fractions in the regression of P fertilizer response with available P. Little Pi was extractable in alkaline solutions (bicarbonate and NaOH), particularly in soils from the Brown and Dark Brown soil zones. Alkaline fractions were the most closely related to resin P, but the relationship depended on soil zone. Inorganic P extractable in dilute HCl was most strongly correlated with soil pH, reflecting accumulation in calcareous soils, while Pi extractable in concentrated acids (HCl and H2SO4) was most strongly correlated with clay concentration. A positive but weak relationship as observed between these fractions and resin P. Complete fractionation of soil P confirmed that soil test P methods were assessing exchangeable, plant-available P. Key words: Hedley phosphorus fractionation, resin, Olsen, Kelowna

scholarly journals Finnish trends in phosphorus balances and soil test phosphorus

2008 ◽  
Vol 16 (4) ◽  
pp. 301 ◽  
Author(s):  
R. UUSITALO ◽  
E. TURTOLA ◽  
J. GRÖNROOS
Keyword(s):  
Agricultural Soils ◽  
Animal Production ◽  
Plant Production ◽  
Major Influence ◽  
Soil Test ◽  
P Loss ◽  
P Concentration ◽  
Soil Test P ◽  
Soil Test Phosphorus ◽  
Yield Responses

Soil test phosphorus (P) concentration has a major influence on the dissolved P concentration in runoff from agricultural soils. Thus, trends in soil test P partly determine the development of pollution potential of agricultural activities. We reviewed the changes of soil test P and P balances in Finnish agriculture, and assessed the current setting of P loss potential after two Agri-Environmental Programs. Phosphorus balance of the Finnish agriculture has decreased from +35 kg ha–1 of the 1980’s to about +8 kg P ha–1 today. As a consequence, the 50-yr upward trend in soil test P concentrations has probably levelled out in the late 1990’s, as suggested by sampling of about 1600 fields and by a modelling exercise. For the majority of our agricultural soils, soil test P concentrations are currently at a level at which annual P fertilization is unlikely to give measurable yield responses. Soils that benefit from annual P applications are more often found in farms specialized in cereal production, whereas farms specialized in non-cereal plant production and animal production have higher soil test P concentrations. An imbalance in P cycling between plant (feed) and animal production is obvious, and regional imbalances are a result of concentration of animal farms in some parts of the country. A major concern in future will be the fate of manure P in those regions where animal production intensity is further increasing.;

Yield benefit of phosphorus fertilizer for wheat, barley and canola in Alberta

2003 ◽  
Vol 83 (4) ◽  
pp. 431-441 ◽  
Author(s):  
R. H. McKenzie ◽  
E. Bremer ◽  
L. Kryzanowski ◽  
A. B. Middleton ◽  
E. D. Solberg ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Brassica Napus ◽  
Hordeum Vulgare ◽  
Soil Types ◽  
Yield Response ◽  
Soil Test ◽  
Fertilizer Response ◽  
Wide Range ◽  
P Fertilizer ◽  
Soil Test P

Crop responsiveness to P fertilizers on the Canadian Prairies has likely declined during the past three to four decades due to regular application of P fertilizer and reduced tillage. Its relationship to extractable soil P as determined by various soil tests may also have changed. The objective of this study was to evaluate five soil test P methods for three major crops across a wide range of soil types and environmental conditions. Small-plot P fertilizer trials were conducted at 154 locations across Alberta from 1991 through 1993. At each location, fertilizer responses were determined for one, two, or three crops: barley (Hordeum vulgare L.), spring wheat (Triticum aestivum L.) or canola (Brassica napus L.). Fertilizer treatments consisted of seed-placed monoammonium phosphate at rates of 0, 6.5, 13.1 and 19.6 kg P ha-1. The average increase in seed yield due to application of P fertilizer was 10%, with little difference among crop types. Relative yield increases were significantly greater in Gray soils (Dark Gray Chernozemics, Dark Gray-Gray Luvisols) than in Black (Black Chernozemics) or Brown soi ls (Brown and Dark Brown Chernozemics). The maximum variation in P fertilizer response accounted for by any soil test P was 27% for barley, 15% for wheat and 7% for canola. The Kelowna method and its derivatives generally provided the best fit with P fertilizer response. Only a modest increase in the proportion of variation that could be accounted for by soil test was achieved by multiple regressions with soil pH, clay or organic matter or by separate analyses of different soil types or years. The probability of a profitable yield response due to P fertilizer application did decline with increasing soil test P. However, profitable yield responses were frequent at all levels of soil test P for the first increment of 6.5 kg P ha-1 and low at all levels of soil test P for the third increment of 6.5 kg P ha-1 (19.6 kg P ha-1). The poor relationship of soil test P to fertilizer response was attributed to frequent but variable starter effects of P fertilizer and the infrequent occurrence of highly responsive sites. Key words: Soil testing, Olsen, Bray, Kelowna, fertilizer response functions, Hordeum vulgare, Triticum aestivum, Brassica napus

Yield response of barley and rapeseed to P fertilizer: Influence of soil test P level and method of placement

1993 ◽  
Vol 24 (1-2) ◽  
pp. 1-10 ◽  
Author(s):  
S. S. Malhi ◽  
M. Nyborg ◽  
D. C. Penney ◽  
L. Kryzanowski ◽  
J. A. Robertson ◽  
...  
Keyword(s):  
Yield Response ◽  
Soil Test ◽  
P Fertilizer ◽  
Soil Test P ◽  
Method Of Placement

scholarly journals Tomato Yield and Fruit Size Did Not Respond to P Fertilization of a Sandy Soil Testing Very High in Mehlich-1 P

HortScience ◽  
1999 ◽  
Vol 34 (4) ◽  
pp. 653-656 ◽  
Author(s):  
George Hochmuth ◽  
Osmar Carrijo ◽  
Ken Shuler
Keyword(s):  
Fruit Size ◽  
Yield Response ◽  
Soil Test ◽  
P Fertilization ◽  
Marketable Yield ◽  
Size Category ◽  
Tomato Yield ◽  
P Fertilizer ◽  
P Application ◽  
Very High

Tomato (Lycopersicon esculentum Mill.) was grown in southeastern Florida on sandy soils that tested very high in Mehlich-1 P to evaluate the yield response to P fertilization. One location was used in 1995–96, another in 1996–97. Prefertilization soil samples contained 290 (location 1) and 63 (location 2) mg·kg–1 Mehlich-1 P. Both soil test results were interpreted as very high in P, and P fertilizer was not recommended for the crop. Fertilizer treatments at both sites were 0, 25, 50, 100, 150, and 200 kg·ha–1 P. Neither total marketable yield nor yield in any fruit size category was affected by P fertilization in either season. Amounts of cull (undersized or misshapened) fruits increased quadratically with P fertilization in the second season. Whole-leaf P concentrations increased linearly or quadratically with P application, depending on sample periods, and were always above sufficiency values. Although many tomato growers apply P fertilizer irrespective of soil test recommendations, our results showed that added P was not needed on soils testing very high in P. Furthermore, withholding P applications to soils with high P concentrations will minimize potential P pollution of surface water and groundwater.

scholarly journals Effects of repeated phosphorus fertilisation on field crops in Finland 1.Yield responses on clay and loam soils relation to soil test P values

2008 ◽  
Vol 15 (2) ◽  
pp. 106 ◽  
Author(s):  
I. SAARELA ◽  
Y. SALO ◽  
M. VUORINEN
Keyword(s):  
Ammonium Acetate ◽  
Field Studies ◽  
Soil Test ◽  
P Values ◽  
Extractable P ◽  
Soil Test P ◽  
Significant Yield ◽  
The Mean ◽  
Yield Responses ◽  
Phosphorus Fertilisation

In order to update phosphorus (P) fertiliser recommendations for the Finnish clay and loam soils enriched with applied P, the effects of repeated P fertilisation on the yields of cereal and other crops were measured at eight sites over a period of 12-18 years. Yield results of some earlier field studies were also used in calibrating the soil test P values determined by the Finnish acid ammonium acetate method (PAc). Significant yield responses to P fertilisation were obtained on soils which had low PAc values or medium levels of PAc and too low or too high pH values (< 6.0 or 7.5 in water suspension). The mean relative control yield (RCY, yield without applied P divided by yield with sufficient P multiplied by 100) of the eight sites was 94.6% (n = 128, mean PAc 15.5 mg dm-3) varying from 87% at PAc 2.8 mg dm-3 to 100% at high PAc. A PAc level of 5-7 mg dm-3 was adequate for cereals, grasses and oilseed rape on the basis of the RCY value of 95% at optimal pH. At this PAc replacing the amounts of P in the crops (14 kg in 4 t grain) and the fixation of extractable P (about 6 kg ha-1 a-1) produced almost maximum yields in favourable seasons and were considered optimal.;

scholarly journals 651 PB 025 FERTILIZER BANDING REDUCES P INPUTS INTO COMMERCIAL LETTUCE PRODUCTION ON HISTOSOLS

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 526a-526
Author(s):  
N. M. El-Hout
Keyword(s):  
Field Experiments ◽  
Soil Test ◽  
Band Placement ◽  
Pooled Data ◽  
P Fertilizer ◽  
P Rate ◽  
Soil Test P ◽  
Large Production ◽  
Use Efficiency ◽  
Environmentally Sensitive

Band placement has been recognized as an effective strategy for improving P fertilizer-use efficiency on Histosols, which are often characterized as environmentally sensitive wetlands, and for reducing P loading of drainage waters from these soils. Recent studies indicate that crisphead lettuce (Lacruca sativa L.) yields can be optimized with a band-P rate one-third of that required with broadcast applications. However, such findings have not been verified in large production plots. Five field experiments were conducted between 1991 and 1993 to evaluate the response of crisphead lettuce produced commercially on Histosols to band P rates. Liquid P fertilizers were placed in lo-cm-wide strips, 8.5-cm below the seed at planting in rates ranging from 0 to 224 kg P ha-1. Lettuce yields increased significantly with P rate in all experiments. Irrespective of initial soil-test-P index, lettuce yields within each experiment were maximized with a band rate 54% of that required in a broadcast. The pooled data for all experiments showed a similar trend. These findings provided a means of making alternative band fertilizer recommendations by utilizing an existing preplant broadcast soil test.

Soil properties as predictors of yield response of clover (Trifolium subterraneum L.) to added P in soils of varying P sorption capacity

Soil Research ◽  
2003 ◽  
Vol 41 (4) ◽  
pp. 653 ◽  
Author(s):  
R. F. Brennan ◽  
M. D. A. Bolland
Keyword(s):  
Soil Properties ◽  
Response Curve ◽  
Maximum Yield ◽  
Trifolium Subterraneum ◽  
Stepwise Multiple Regression ◽  
Yield Response ◽  
Soil Test ◽  
Organic Carbon Content ◽  
Soil Test P ◽  
Yield Responses

Thirty-five unfertilised soils collected in south-western Australia were used to measure the effect of soil properties on (i) shoot yield responses of 50-day-old clover (Trifolium subterraneum L. cv. Nungarin) plants to applied phosphorus (P), and (ii) extractability of bicarbonate soil test P (slope of the linear relationship between Colwell P and the amount of P applied). Data for the relationship between shoot yield and the amount of P applied were fitted to a rescaled Mitscherlich equation to calculate the amount of P required to produce 50% and 90% of the maximum yield (P50% and P90%) and determine the curvature (c) and n coefficients of the equation. When the value of n is 1.00, the response curve is exponential, and as the value of n increases above 1.00 the response curve becomes more sigmoidal. The c, n, P50%, P90%, and extractability values were related to properties of the 35 soils.There was a significant (P < 0.05) trend for the values of c and extractability to decrease as the capacity of the soil to sorb P increased. Consequently, as the soil sorbed more P, the trend was that (1) more P needed to be applied to produce the same yield, so both P50% and P90% tended to significantly (P < 0.05) increase; (2) shoot yield responses to applied P became more sigmoidal so the value of the n coefficient tended to significantly (P < 0.05) increase; (3) more P needed to be applied to a soil to produce the same soil test P value; and (4) larger soil test P values were needed to produce the same yield. No single soil property adequately predicted P50%, P90%, extractability, c, or n. Stepwise multiple regression indicated that (1) clay content and P buffer capacity (PBC) of soil together accounted for 48% of the variation in P50%, 56% of the variation in P90%, and 52% of the variation in c; (2) PBC and soil pH together accounted for 17% of the variation in n; and (3) PBC, percentage clay and percentage organic carbon content of soil together accounted for 68% of the variation in extractability.

Sign in / Sign up

Export Citation Format

Share Document