scholarly journals Effect of Spacing and Fertilization on the Yield of Potatoes

1969 ◽  
Vol 39 (2) ◽  
pp. 100-110
Author(s):  
Pablo Landrau, Jr. ◽  
Juan Pastor Rodríguez ◽  
George Samuels ◽  
Severiano Alers Alers ◽  
R. Gandía Caro
Keyword(s):  
Potato Variety ◽  
Clay Soil ◽  
Potato Seed ◽  
Phosphorus Fertilizers ◽  
The Mean ◽  
Phosphorus And Potassium ◽  
Potato Yields ◽  
Planting Distance ◽  
Nitrogen Phosphorus

Combined fertilizer and spacing experiments with potatoes were conducted at Corozal on Lares clay soil, at Isabela on a Coto clay soil, and at Aibonito on a Juncos clay soil. The experiments were planted in December 1953 and January 1954. The areas were located at different elevations with variation in soils and climate. The potato variety Kennebec, resistant to blight, was planted. The major results were: 1. Nitrogen did not consistently increase the yield of potatoes significantly. 2. Phosphorus increased the yield of potatoes most. 3. Potassium failed to increase the yield of potatoes significantly. 4. The Coto clay soil gave the highest yield increases attributable to the use of phosphorus fertilizers. 5. The 6-inch planting distance gave the highest potato yields in all three experiments. 6. The interaction between fertilizer and planting distance, or number of potato seed pieces planted per acre, was not significant. As the number of seed pieces increased there was no need for higher rates of fertilizer applications. 7. A highly significant correlation was obtained between number of potato seed pieces planted per acre and yield in all three experiments. This relationship indicates that, as the number of seed pieces increases, the yields also increase. 8. For all three experiments the mean reductions in yield caused by the omission of nitrogen, phosphorus, and potassium were 15.2, 28.5, and 6.3 percent, respectively. 9. Taking yield at 6-inch spacings as 100, the reduction in yield at 9 inches was 15.6, at 12 inches 20.5, at 15 inches 30.3, and at 18 inches 38.1 percent.

A comparison of the fine root component of a pure and a mixed coniferous stand

1988 ◽  
Vol 18 (11) ◽  
pp. 1416-1426 ◽  
Author(s):  
H. M. McKay ◽  
D. C. Malcolm
Keyword(s):  
Fine Roots ◽  
Standing Crop ◽  
Fine Root ◽  
Sitka Spruce ◽  
Nitrogen And Phosphorus ◽  
Mixed Stands ◽  
Method Of Calculation ◽  
The Mean ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

Fine roots were sampled at monthly intervals during 1984–1985 in pure plots of Sitka spruce (Piceasitchensis (Bong.) Carr.) and mixed plots of Scots pine (Pinussylvestris L.) and Sitka spruce established on an upland heath in 1969. Both types of planting had received phosphorus and potassium fertiliser but no nitrogen. The mean standing crop of live roots (<2 mm diameter) in the top 5 cm of pure spruce plots was 112 g • m−2, almost double that of mixed stands (37 g • m−2 of spruce plus 20 g • m−2 of pine). Necromass was 80% of total mass in both stand types. Concentrations of nitrogen and phosphorus were greater in pure plots than in mixed plots, but fine root capital of nitrogen, phosphorus, and potassium was greater in pure spruce than in mixed plots (biomass and necromass contained 11, 2, and 5 and 45, 4, and 7 kg • ha−1 of nitrogen, phosphorus, and potassium, in pure plots, and 7, 1, and 3 and 30, 3, and 3 kg • ha−1 of nitrogen, phosphorus, and potassium in mixed plots, respectively). Production of fine roots in pure and mixed stands was estimated at 181 and 97 g • m−2•year−1 or 715 and 367 g • m−2•year−1, respectively, depending on the method of calculation. Fine roots of pure plots were highly concentrated in the top 3 cm. In mixture, spruce roots had a less extreme vertical distribution and pine roots were more evenly distributed down to 9 cm.

scholarly journals RESPONSE OF FOUR SUGARCANE VARIETIES TO FERTILIZERS DURING THE FIRST ISABELA CYCLE, 1946-51

1969 ◽  
Vol 38 (2) ◽  
pp. 73-95
Author(s):  
Pablo Landrau, Jr. ◽  
George Samuels
Keyword(s):  
Dry Matter ◽  
Phosphorus Deficiency ◽  
Phosphate Fertilizers ◽  
Sugarcane Varieties ◽  
The Third ◽  
Fertilizer Experiment ◽  
The Mean ◽  
Phosphorus And Potassium ◽  
Yield Responses ◽  
Nitrogen Phosphorus

A variety-fertilizer experiment using four varieties of sugarcane grown at seven different fertilizer levels was carried on for a plant cane and three ratoons at the Isabela Substation on a Coto clay. The major results were: (1) Nitrogen gave the highest yield increases in hundredweights of 96° available sugar per acre. (2) Phosphate fertilizers gave significant increases in yields of cane for the ratoon crops. (3) Potasium fertilizers did not increase the yield of sugar per acre. (4) Applications of nitrogen, phosphorus, or potassium did not significantly influence sucrose concentrations in the cane. (5) The leading two varieties, P.R., 902 and P.R. 905, gave significantly greater yields of sugar per acre than the other two varieties, P.O.J. 2878 and M. 28. (6) All varieties maintained their relative yielding power when tested at various fertilizer levels. (7) The reductions in yield from the omission of a fertilizer element for the mean of four crops were 22, 14, and 4 percent for nitrogen, phosphorus, and potassium, respectively. (8) Foliar analysis was made for leaves of the third ratoon only. Nitrogen values below 1.39-percent dry matter in the leaf represented definite deficiency, and response to nitrogen applications could be expected. Values of 0.16 percent of phosphorus in the leaf represented phosphorus deficiency, while there was no response to phosphates when the percentage was 0.20 or above. The potassium leaf values were above 2 percent and no yield responses were obtained at any potash level.

Uptake of N, P and K by Irrigated and Unirrigated Pearl Millet (Pennisetum Typhoides)

1979 ◽  
Vol 15 (3) ◽  
pp. 217-223 ◽  
Author(s):  
P. J. Gregory
Keyword(s):  
Nutrient Uptake ◽  
Pearl Millet ◽  
Dry Weight ◽  
Grain Filling ◽  
Nutrient Content ◽  
Fertilizer Placement ◽  
Pennisetum Typhoides ◽  
The Mean ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

SUMMARYUptake of nitrogen, phosphorus and potassium was measured for irrigated and unirrigated crops of pearl millet grown at Hyderabad, India. Irrigation slightly increased the concentration of nutrients in the crop and this, together with a higher dry weight, resulted in the nutrient content at harvest (day 82) being approximately twice that of the dry crop. Nutrient uptake by the latter ceased at about day 40 whereas the irrigated crop continued to take up nutrients for a further 7–21 days. However, both crops showed the importance of redistribution of nutrients from leaves and stems during the grain filling. The mean rate of nutrient uptake per metre of root per day (inflow) fell throughout growth in contrast with the rate of nutrient uptake per plant, which reached a maximum at about days 26 to 33. These findings are discussed in relation to possible strategies for fertilizer placement.

scholarly journals Effect of cultivation distances on growth and productivity of two varieties of garlic under the conditions of El jabal Al-Akhdar

2019 ◽  
pp. 79-100
Author(s):  
Firas S. Abubaker ◽  
Ali M. Khalifa ◽  
Hasan B. Albaba ◽  
Suliman A. Jadallh
Keyword(s):  
Average Length ◽  
Total Yield ◽  
Dry Weight ◽  
Average Weight ◽  
Nitrogen And Phosphorus ◽  
Number Of Leaves ◽  
Total Crop ◽  
The Mean ◽  
Phosphorus And Potassium ◽  
Planting Distance

The research was carried out by the Department of Horticulture - Faculty of Agriculture - University of Omar Al-Mukhtar - White during the 2013-2014 and 2014-2015 planting seasons. To study the effect of four planting distances (5, 7.5, 10, 12.5 cm) on the behavior of two varieties of garlic (Egyptian "municipal", Chinese). The design of full randomized splitters was used once in three replicates. The mean of the treatments was measured according to the Duncan test at a significant level of 5%. The results showed that the gradual increase of the planting distance (5, 7.5, 10, 12.5 cm) resulted in a gradual and significant increase in the average length of the leaves, the average number of leaves, the paper area and the dry weight of the leaves in both cultivars. The best results for the leaf content of nitrogen and phosphorus at planting distance were 12.5 cm, while potassium was at a distance of 5 cm. The content of the leaves of chlorophyll (A, B) in both cultivars increased by increasing the distance of cultivation with the superiority of the Chinese class on the Egyptian. The results showed that increasing the planting distance to 12.5 cm increased the average weight of the bulb, the exportable yield and the exportable yield of the total crop, while the total yield decreased with the increase of the planting distance. The highest percentage of nitrogen was recorded at a distance of 12.5 cm for the Egyptian variety, while the Chinese category recorded the highest percentage of phosphorus and potassium. The results showed no significant differences in mean weight of the lobes between the four planting distances of the Egyptian and Chinese varieties during the first and second seasons. The best results were achieved for total dissolved solids at a distance of 12.5 cm in the Chinese and Egyptian varieties, respectively.

scholarly journals Chemical Properties of Soil Influence by Sewage Water Irrigation of Different District of Haryana

2019 ◽  
pp. 1-7
Author(s):  
Sushil . ◽  
R. S. Garhwal ◽  
Md. Sarware Alam ◽  
Deepika Rathi ◽  
Dinesh .
Keyword(s):  
Chemical Properties ◽  
Sewage Water ◽  
Mean Value ◽  
Well Water ◽  
The Mean ◽  
Tube Well ◽  
The Difference ◽  
Phosphorus And Potassium ◽  
Soil Influence ◽  
Nitrogen Phosphorus

The present study deals with the difference of chemical properties between sewage and tube well water irrigated soils. Samples were collected from sewage and tube well water irrigated soil of various site like Kaithal, Narwana and Jind district of Haryana state where these waters are directly used for irrigating the crops. Soil samples (0-15 and 15-30 cm) were also collected from fields irrigated with these waters and from nearby fields irrigated with non-sewage waters to determine the changes in soil chemical properties due to sewage irrigation. Total Zn, Cu, Mn, Fe, Cd, Pb, Co, and Cr along with nitrogen, phosphorus and potassium were estimated form the samples. The mean value of N (200.50 kg ha-1) was found highest in the soils irrigated with sewage water of Kaithal. The mean value of P (35.85 kg ha-1) and K (236.40 kg ha-1) was found highest in the soils irrigated with sewage water of Jind. The mean value of K (236.40 kg ha-1) was found highest in the soils irrigated with sewage water of Jind. The mean value of Zn (4.43 mg kg-1), Cu (3.33 mg kg-1) and Fe (19.43 mg kg-1) was found highest in the soils irrigated with sewage water of Jind. The mean value of Mn (15.13 mg kg-1) was found highest in the soils irrigated with sewage water of Kaithal. The DTPA extractable heavy metals like Cd, Pb and Co were found higher in the soils irrigated with sewage water as compared to soils irrigated with non-sewage water. The value of Cr content was found nil all the soils samples collected from different cities from sewage and non-sewage water irrigated sites.

Effects of Water-Nitrogen Interaction on Absorption, Translocation and Distribution of Nitrogen, Phosphorus, and Potassium in Rice

2010 ◽  
Vol 36 (4) ◽  
pp. 655-664 ◽  
Author(s):  
Yong-Jian SUN ◽  
Yuan-Yuan SUN ◽  
Xu-Yi LI ◽  
Rong-Ping ZHANG ◽  
Xiang GUO ◽  
...  
Keyword(s):  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

scholarly journals Effects of serpentinite fertilizer on the chemical properties and enzyme activity of young spruce soils

2016 ◽  
Vol 30 (4) ◽  
pp. 401-414 ◽  
Author(s):  
Ewa Błońska ◽  
Kazimierz Januszek ◽  
Stanisław Małek ◽  
Tomasz Wanic
Keyword(s):  
Enzyme Activity ◽  
Chemical Properties ◽  
Molar Ratio ◽  
Tree Roots ◽  
Forest Zone ◽  
Negative Effect ◽  
Phosphorus And Potassium ◽  
One Year ◽  
Nitrogen Phosphorus ◽  
Experimental Plots

AbstractThe experimental plots used in the study were located in the middle forest zone (elevation: 900-950 m a.s.l.) on two nappes of the flysch Carpathians in southern Poland. The aim of this study was to assess the effects of serpentinite in combination with nitrogen, phosphorus, and potassium fertilizers on selected chemical properties of the soil and activity of dehydrogenase and urease in the studied soils. All fertilizer treatments significantly enriched the tested soils in magnesium. The use of serpentinite as a fertilizer reduced the molar ratio of exchangeable calcium to magnesium, which facilitated the uptake of magnesium by tree roots due to competition between calcium and magnesium. After one year of fertilization on the Wisła experimental plot, the pH of the Ofh horizon increased, while the pH of the mineral horizons significantly decreased. Enrichment of serpentinite with nitrogen, phosphorus, and potassium fertilizers stimulated the dehydrogenase activity in the studied organic horizon. The lack of a negative effect of the serpentinite fertilizer on enzyme activity in the spruce stand soil showed that the concentrations of the heavy metals added to the soil were not high enough to be toxic and indicated the feasibility of using this fertilizer in forestry.

scholarly journals Effects of nitrogen, phosphorus and potassium rates on Microdochium patch

itsrj ◽  
2021 ◽  
Author(s):  
Brian McDonald ◽  
Alec Kowalewski ◽  
Clint Mattox ◽  
Emily Braithwaite ◽  
Charles Schmid
Keyword(s):  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

scholarly journals Phytotoxic effects of invasive Ageratina adenophora on two native subtropical shrubs in Nepal

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tej Bahadur Darji ◽  
Barsha Adhikari ◽  
Seeta Pathak ◽  
Shristi Neupane ◽  
Lal B. Thapa ◽  
...  
Keyword(s):  
Low Ph ◽  
Potential Mechanism ◽  
Phytotoxic Effects ◽  
Seedling Length ◽  
Ageratina Adenophora ◽  
Ir Analysis ◽  
Allelopathic Interference ◽  
Phosphorus And Potassium ◽  
Native Shrubs ◽  
Nitrogen Phosphorus

AbstractThe response of native plants to allelopathic interference of invasive species may differ from species to species. In this study, the phytotoxic effects of Ageratina adenophora were tested on two native shrubs (Osbeckia stellata and Elsholtzia blanda) of Nepal. Both the shrubs were grown in pots under treatments of A. adenophora fresh leaves and root leachates, and litter. Then, the seedling length and biomass were compared among the treatments. The results show that A. adenophora litter has stimulatory effects but the leachates from fresh leaves and root are phytotoxic to the growth and development of native shrubs. Infrared Spectroscopy (IR) analysis confirmed the presence of O–H (Hydroxyl), N–H (Amines), C≡C (Alkynes), and C–H stretching (Aromatic) or C–O–C stretching (Ethers) in the leachates representing harmful allelochemicals. The invaded soil by A. adenophora had low pH and a high amount of organic matter, total nitrogen, phosphorus, and potassium than the uninvaded soil. The results indicate that the native O. stellata and E. blanda are harmed by A. adenophora in nature by leaching of allelochemicals and probably by reducing the soil pH. Overall, this study has provided valuable insights regarding the effects of A. adenophora invasion on native shrubs and revealing the potential mechanism of its invasiveness.

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