The early prognosis of tuber yield based on nitrogen status in potato tops

The pattern of nitrogen net change (ΔN) in potato tops during the period extending from BBCH 33 to BBCH 40 is crucial for tuber yield (TY). This hypothesis was verified based on data from field experiments (2006–2008) with sequentially added nutrients (0, NP, NPK, NPKS, NPKSMg) to potato. The water shortage in June/July 2006 and in June 2008 significantly affected N content, and in turn TY. The TY was reduced by 38% in 2006 and by 23% in 2008, as compared to 2007 (53.7 t/ha). The N content in potato tops at BBCH 40 of 2.5% indicated the lowest TY, whereas 4.3% the maximum TY. The ΔN of +0.4% within the period from BBCH 33 to BBCH 40 determined the optimal range of the N content for the maximum TY (3.9–4.3%). The ΔN trend depended on the change of phosphorus and potassium contents. The key reason of N inefficiency was the shortage of potassium (K), resulting in its negligible change within this period. The pattern of zinc content at BBCH 40 reflected fairly well disturbances in N as well as K supply to potato. A good supply of K and Zn to potato can improve N management just before tuber initiation.

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Estimating Crop Nutritional Status Using Smart Apps to Support Nitrogen Fertilization. A Case Study on Paddy Rice

Sensors ◽

10.3390/s19040981 ◽

2019 ◽

Vol 19 (4) ◽

pp. 981 ◽

Cited By ~ 4

Author(s):

Livia Paleari ◽

Ermes Movedi ◽

Fosco Vesely ◽

William Thoelke ◽

Sofia Tartarini ◽

...

Keyword(s):

Environmental Sustainability ◽

Field Experiments ◽

Cropping Systems ◽

Diagnostic System ◽

N Fertilization ◽

Paddy Rice ◽

N Content ◽

Area Index ◽

Widespread Availability ◽

N Management

Accurate nitrogen (N) management is crucial for the economic and environmental sustainability of cropping systems. Different methods have been developed to increase the efficiency of N fertilizations. However, their costs and/or low usability have often prevented their adoption in operational contexts. We developed a diagnostic system to support topdressing N fertilization based on the use of smart apps to derive a N nutritional index (NNI; actual/critical plant N content). The system was tested on paddy rice via dedicated field experiments, where the smart apps PocketLAI and PocketN were used to estimate, respectively, critical (from leaf area index) and actual plant N content. Results highlighted the system’s capability to correctly detect the conditions of N stress (NNI < 1) and N surplus (NNI > 1), thereby effectively supporting topdressing fertilizations. A resource-efficient methodology to derive PocketN calibration curves for different varieties—needed to extend the system to new contexts—was also developed and successfully evaluated on 43 widely grown European varieties. The widespread availability of smartphones and the possibility to integrate NNI and remote sensing technologies to derive variable rate fertilization maps generate new opportunities for supporting N management under real farming conditions.

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Potato (Solanum tuberosum L.) Tuber Yield and Yield Components as Influenced by Different Levels of Nitrogen, Phosphorus and Potassium in Rwanda

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-155 ◽

2019 ◽

Vol 39 (03) ◽

Author(s):

Adrien Turamyenyirijuru ◽

Guillaume Nyagatare ◽

Robert Morwani Gesimba ◽

Rhoda Jerop Birech

Keyword(s):

Yield Components ◽

Field Experiments ◽

Tuber Yield ◽

Solanum Tuberosum L ◽

Block Design ◽

Yield Potential ◽

Ecological Zones ◽

Growing Seasons ◽

Yield And Yield Components ◽

Phosphorus And Potassium

Despite potato yield potential, its intensification level remain low in Rwanda, translating into low yield occasioned mainly by the decline in soil fertility. Field experiments were conducted in Birunga, Mudende [L1]) and Buberuka, Rwerere [L2] highlands Agro-Ecological Zones (AEZs), during September- December 2016 and March-June 2017 crop growing seasons to determine the effects of varying rates of N, P and K on potato tuber yield and yield components. The experiments were laid out using randomized complete block design with factorial arrangement, with four replicates. Factors were N rates (NX) i.e N1-0 kg ha-1, N2 – 50 kg ha-1, N3 – 100 kg ha-1 ; P2O5 rates (PX) i.e P1-0 kg ha-1, P2 – 50 kg ha-1, P3 – 100 kg ha-1and K2O rates (Kx) i.e K1- 0 kg ha1and K2- 50 kg ha-1. Number of tubers per plant, fresh tuber weight, small tuber yield, medium tuber yield, large tuber yield and total tuber yield were measured. Analysis of variance, performed using SAS-version 9.2, revealed that interaction effects of N×P×K were very highly significant on all parameters. Generally, N3×P3×K2 performed better than other treatments and recorded highest tuber yields in all situations: (32.73 ± 0.43) t ha-1[L1] and (29.36 ± 0.41) t ha-1 [L2] and (31.05 ± 0.52) t ha-1for pooled ANOVA. Contrarily to what happened at L2, N3P3K2 andN2P3K2 were not significantly different at L1. N2P3 K2 is recommended to L1 whereas N3P3K2 is recommended to L2.

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Influence of Nitrogen Nutrition Management on Biomass Partitioning and Nitrogen Use Efficiency Indices in Hydroponically Grown Potato

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.129.1.0134 ◽

2004 ◽

Vol 129 (1) ◽

pp. 134-140 ◽

Cited By ~ 13

Author(s):

Gregory D. Goins ◽

Neil C. Yorio ◽

Raymond M. Wheeler

Keyword(s):

Biomass Production ◽

Nutrient Solution ◽

Tuber Yield ◽

N Use Efficiency ◽

Tuber Initiation ◽

N Supply ◽

Long Duration ◽

Use Efficiency ◽

N Management ◽

N Use

The National Aeronautics and Space Administration (NASA) has been conducting controlled environment research with potatoes (Solanum tuberosum L.) in recirculating nutrient film technique (NFT)-hydroponic systems as a human life support component during long-duration spaceflight. Standard nutrient solution management approaches include constant pH regulation with nitric acid (HNO3) and daily adjustment of electrical conductivity (EC) equivalent to half-strength modified Hoagland's solution, where nitrate (NO3-) is the sole nitrogen (N) source. Although tuber yields have been excellent with such an approach, N use efficiency indices are expected to be low relative to tuber biomass production. Furthermore, the high amount of N used in NFT-hydroponics, typically results in high inedible biomass, which conflicts with the need to minimize system mass, volume, and expenditure of resources for long-duration missions. More effective strategies of N fertilization need to be developed to more closely match N supply with demand of the crop. Hence, the primary objective of this study was to identify the optimal N management regime and plant N requirement to achieve high yields and to avoid inefficient use of N and excess inedible biomass production. In separate 84-day cropping experiments, three N management protocols were tested. Treatments which decreased NO3--N supply indirectly through lowering nutrient solution EC (Expt. I), or disabling pH control, and/or supplying NH4+-N (Expt. III) did not significantly benefit tuber yield, but did influence N use efficiency indices. When supplied with an external 7.5 mm NO-3--N for the first 42 days after planting (DAP), lowered to 1.0 mm NO3 -N during the final 42 days (Expt. II), plants were able to achieve yields on par with plants which received constant 7.5 mm NO3--N (control). By abruptly decreasing N supply at tuber initiation in Expt. II, less N was taken up and accumulated by plants compared to those which received high constant N (control). However, proportionately more plant accumulated N was used (N use efficiency) to produce tuber biomass when N supply was abruptly lowered at tuber initiation in Expt. II. Hence, a hydroponic nutrient solution N management system may be modified to elicit greater plant N-use while maintaining overall high tuber yield as opposed to achieving high tuber yields through excess N supply and shoot growth.

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Reduced Dosage of Methyl Bromide for Controlling Verticillium Wilt of Potato in Experimental and Commercial Plots

Plant Disease ◽

10.1094/pdis.1997.81.5.469 ◽

1997 ◽

Vol 81 (5) ◽

pp. 469-474 ◽

Cited By ~ 27

Author(s):

A. Gamliel ◽

A. Grinstein ◽

Y. Peretz ◽

L. Klein ◽

A. Nachmias ◽

...

Keyword(s):

Verticillium Wilt ◽

Methyl Bromide ◽

Large Scale ◽

Field Experiments ◽

Tuber Yield ◽

Total Yield ◽

Effective Control ◽

Large Scale Field ◽

Commercial Applications

The use of gas-impermeable films to reduce the dosage of methyl bromide (MB) required to control Verticillium wilt in potatoes was examined in field experiments, conducted in soils naturally infested with Verticillium dahliae. The incidence and severity of Verticillium wilt were significantly reduced (by 74 to 94%) by fumigation with MB at 50 g/m2 under standard low density polyethylene (LDPE) or at 25 g/m2 under gas-impermeable films. Fumigation at 25 g/m2 under LDPE was less effective. Disease severity was inversely correlated (r2 = 0.89 to 0.91) with chlorophyll content in the leaves. Fumigation also reduced (by 89 to 100%) stem colonization by the pathogen. Potato yield in the fumigated plots was significantly higher (26 to 69%), than in their nonfumigated counterparts, and was inversely correlated with disease index (r2 = 0.69 to 0.9). The percentage of high-value tubers (above 45 g) was 52 to 56% of total yield in the fumigated plots as compared with 32 to 40% in the nonfumigated controls. Thus, fumigation also improved the commercial quality of tuber yield. Effective control of V. dahliae and yield increases following MB fumigation at the recommended dosage or at a reduced dosage with gas-impermeable films was also observed in a consecutive crop. These results were verified in a large-scale field experiment using commercial applications, further demonstrating the feasibility of reducing MB dosages under farm conditions, without reducing its effectiveness in terms of disease control and yield improvement.

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Effect of nitrogen, phosphorus and potassium application on yield of potato tubers (Solatium tuberosum L.)

The Journal of Agricultural Science ◽

10.1017/s0021859600079326 ◽

1987 ◽

Vol 108 (2) ◽

pp. 321-329 ◽

Cited By ~ 13

Author(s):

U. C. Sharma ◽

B. R. Arora

Keyword(s):

Field Experiments ◽

Sandy Loam ◽

Farmyard Manure ◽

Potato Tubers ◽

Solatium Tuberosum ◽

Loam Soil ◽

Potassium Application ◽

Phosphorus And Potassium ◽

Grade Increase ◽

Nitrogen Phosphorus

SummarySix field experiments, three each during 1982–3 and 1983–4, were conducted on a sandy loam soil to study the effect of varying levels of nitrogen, phosphorus and potassium, in the absence and presence of farmyard manure (FYM) (30 t/ha), on the number of tubers and yield of potato in three grades. Increase in nitrogen, phosphorus and potassium application, in the absence or presence of FYM, did not significantly affect the total number of tubers/m2 but did affect the number of tubers in different grades. An increase in nitrogen and potassium significantly decreased the number of tubers/m2 in small (< 25 g) and increased in medium (25–75 g) and large (> 75 g) grades at 45, 60, 75 and 90 days after planting. Increase in the application of phosphorus increased the number of tubers/m2 in the small grade and decreased it in the large grade but did not affect the number in the medium grade. Increase in nitrogen and potassium application decreased the tuber yield in the small grade and increased it in the medium and large grades. Applied phosphorus increased the yield in the small and medium grades and decreased it in the large grade. The increase in the yield of tubers with increase in nitrogen and potassium application was found to be caused by an increase in the number of tubers in the medium and large grades at the expense of the small grade; however, with applied phosphorus the increase in yield was due to increase in the weight of individual tubers within the small and medium grades. FYM application decreased the number of tubers in the small grade and increased it in the medium and large grades. The response of potato to nitrogen increased and to phosphorus and potassium decreased with the application of FYM.

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Enhancing Soil Fertility through Intercropping, Inoculation and Fertilizer

Biological Sciences - PJSIR ◽

10.52763/pjsir.biol.sci.59.1.2016.1.5 ◽

2016 ◽

Vol 59 (1) ◽

pp. 1-5

Author(s):

Muhammad Arshad Ullah ◽

Nazir Hussain ◽

Helge Schmeisky ◽

Muhammad Rasheed

Keyword(s):

Plant Uptake ◽

Field Experiments ◽

Fertilizer Application ◽

Research Centre ◽

Vicia Sativa ◽

Soil N ◽

N Content ◽

Seed Inoculation ◽

Crop Harvest ◽

Total Soil N

The present study was conducted to investigate the effects of intercropping grass (Panicummaximum) and legumes (Vicia sativa and cowpeas) alone or coupled with inoculation or fertilizer on soilfertility. The study comprised of two field experiments conducted under rain fed conditions for two years(June, 2005 to September, 2007) at National Agriculture Research Centre, Islamabad, Pakistan. In oneexperiment intercropping (33, 50 and 67%) of grass and legumes alone as well as coupled with seedinoculation were studied while, same set of treatments was combined with fertilizer application at the ratesof 25, 75 and 50 kg/ha (N, P2O5 and K2O) in the second experiment. Total soil N increased by 0.008% dueto symbiotic fixation in addition to plant uptake under best treatment when compared with grass alonewhile, soil organic matter increased by 0.19%. After crop harvest soil N content was determined to behigher in all the treatments of the experiment compared with growing grass alone. Legumes caused rhizobialN fixation that caused an increase in soil N. Similarly, intercropping and inoculation increased this soilcharacteristic that was found to be non-significant in the first crop but later on became significant, especiallywhen intercropping of grass with legumes after seed inoculation was investigated or fertilizer wassupplemented to the crops. Thus, not only grass used the symbiotically fixed N by companion legumesbut also enhanced the soil N content. The effect of fertilizer was not measurable statistically in case of soilorganic matter. This parameter, in general, was not affected significantly when assessed after first cropharvest. Nevertheless, legumes alone or intercropped within grass increased this important soil constituent.Inoculation proved further beneficial in this regard but combination of intercropping (especially 67%)either with seed inoculation or application of fertilizer was found as the best technique for increasing soilorganic matter.

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The effects of the growth-regulating compounds methyl decanoate and 2, 3, 5-triiodobenzoic acid on potato tuber size

The Journal of Agricultural Science ◽

10.1017/s0021859600054708 ◽

1976 ◽

Vol 86 (2) ◽

pp. 251-255

Author(s):

D. C. E. Wurr

Keyword(s):

Potato Tuber ◽

Size Distribution ◽

Tuber Yield ◽

Potato Crop ◽

Total Yield ◽

Tuber Size ◽

Tuber Initiation ◽

Triiodobenzoic Acid ◽

Tuber Size Distribution ◽

Methyl Decanoate

SummaryApplication of methyl decanoate to a potato crop about the time of tuber initiation reduced the total yield and the yield of tubers in the grade 2·5–5·5 cm though neither of these reductions were significant. However, application of 2,3,5-triiodobenzoic acid increased the yield of tubers 2·5–5·5 cm by up to 20% while having no significant effect on total tuber yield. This change in the tuber size distribution was due to a more even partition of photosynthate between tubers and not to an increase in the total number of tubers.

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Effects of potassium and magnesium fertilizers on yield and size distribution of potatoes

The Journal of Agricultural Science ◽

10.1017/s0021859600058007 ◽

1973 ◽

Vol 80 (3) ◽

pp. 369-373 ◽

Cited By ~ 4

Author(s):

K. Simpson ◽

P. Crooks ◽

S. McIntosh

Keyword(s):

Seed Potato ◽

Field Experiments ◽

Total Yield ◽

Tuber Initiation ◽

Factorial Experiments ◽

K Fertilizer ◽

Dry Conditions ◽

History Of ◽

Potato Crops ◽

Low K

SummaryThirteen field experiments were made during 6 years on seed-potato growing farms in south-east Scotland, comparing three rates, 70, 140 and 280 kg K/ha as potassium chloride and four rates of 0–54 kg Mg/ha as kieserite in 3 × 4 factorial experiments.More than 70 kg/ha of potassium increased total yield only at one site, which had a recent history of low K application and very low available K. Yields were decreased by more than 70 kg/ha of potassium at three sites in a season with abnormally dry conditions just after planting. Applied magnesium had little effect on total yield.Extra potassium increased ware yield but decreased seed yield, both consistently, probably because the fertilizer damaged some stolons at or before tuber initiation and fewer tubers developed. The ware/seed ratio was generally increased by extra K, but after the dry spring this ratio was unaltered or reduced. Applied magnesium had little effect on the ratio.Our results suggest that the present rates of K fertilizer, used for commercial seed-potato crops (114–138 kg K/ha) in south-east Scotland are excessive, and a much lower rate of approximately 70 kg K/ha would be adequate except on very low K sites.

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Use of a simple model to study factors affecting the size distribution of tubers in potato crops

The Journal of Agricultural Science ◽

10.1017/s0021859600081788 ◽

1987 ◽

Vol 109 (3) ◽

pp. 563-571 ◽

Cited By ~ 15

Author(s):

K. Z. Travis

Keyword(s):

Mathematical Model ◽

Size Distribution ◽

Field Experiments ◽

Tuber Yield ◽

Tuber Size ◽

Simple Mathematical Model ◽

Factors Affecting ◽

Tuber Size Distribution ◽

Two Parameters ◽

Potato Crops

SummaryA simple mathematical model of the distribution of potato tuber yield between size grades is presented. It has two parameters, μ, a measure of crop tuber size and σ, a measure of the spread of yield across size grades. The model is shown to be useful for the analysis of field experiments, the prediction and physiological study of tuber size distribution, and the economic analysis of management decisions. The model is applied to a variety of dataandthe practical control of tuber size discussed.

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