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Recent Developments in Potato Storage in Europe
Recent development trends and perspectives are to find alternative methods and materials like breeding new varieties, finding biological sprout suppressants, or investing in innovative storage facilities and technologies to meet consumer demands, climatic changes, and regulations. Paper discusses applicability of controlled atmosphere or modified atmosphere storage to potatoes. Forced application of ethylene in sealed store-rooms has been proved to control dormancy. Ozone is used to suppress bacteria in order to reduce the risk of spreading diseases. The use of volatile oil as sprout suppressant is of high interest to small scale organic growers. Main advantages of bin boxes compared to bulk storage are high variability and transportability, gentle handling, and ability to smaller partitioning of varieties. The free convective ventilation of big bin box stores needs special strategies to obtain homogeneous temperature. Absorption refrigerator can be used as cooling system for potato stores. The heat may be provided by a biogas generator plant. Modern climate controllers can be equipped with modules to control CO2 and air humidity. They can be extended with algorithms for potato surface drying and anti-condensing control. Newer control systems have options for weather forecast and online control or monitoring via mobile telephone.
Growth Rates for Potato in India and their Implications for Industry
As potato output increased from 1.3 million t to over 34 million t over the last six decades, India became the planet's second largest potato producer. Nonetheless, this spectacular increase masks a series of less readily apparent tendencies in the growth rates for potato production, area, and yields. While area harvested expanded, the growth for area harvested experienced a series of peaks and valleys; as yields per hectare continuously rose, the growth rate for productivity gradually ground to a halt. This paper analyses the evolution of these and other growth rates for potato in an effort to provide sharper insights into the driving factors behind the increases in production, area harvested, and yields; the most likely future scenario for the potato sector; and, the implications for industry intended to sustain output and utilization in the years ahead. Sub-sector specific recommendations include greater eco-efficiency in cold storage, efforts to explore niches for small-scale processing of French fries to complement industrial scale operations, and renewed promotion of the potato´s nutritional attributes.
Integrated Nutrient Management in Potato Based Cropping Systems in South Bihar Alluvial Plains
A field experiment was conducted at Patna from 2005–06 to 2007–08 on clay loam soil under Trans Gangetic plain to evaluate the effect of four fertility management schedules viz. application of recommended dose of fertilizer to all the crops in the system either alone or in combination with in situ crop residue incorporation in all the crops in the system, in situ green manuring with Sesbania in rice and FYM @ 10 t/ha applied only to winter crop of potato, on productivity and resource use efficiency in three potato based cropping systems viz. potato (Solanum tuberosum L.) – greengram (Vigna radiata L) – rice (Oryza sativa L.), potato-maize (Zea mays L)-rice and potato-onion (Allium cepa L) – rice. Maximum production (60.24 t/ha), net returns (
98,990/ha), B:C ratio (1.13), production efficiency (190.99 kg/ha/day) and monetary return efficiency ( 313.6/ha/day) were recorded in potato-onion-rice cropping system. Potato-greengram-rice cropping system recorded highest value of sustainable yield index, organic C, available N and P in the soil. Green manuring of Sesbania in the cropping system resulted in maximum production, land use efficiency, organic C, available N, P and K in soil, while application of FYM @ 10 t/ha to potato crop in the system resulted in highest net returns, B:C ratio, production efficiency, monetary return efficiency and sustainable yield index.
Long-Term Effect of Organic Fertilizers on Soil Properties
Consequences of the use of different organic fertilizers (green manure, cereal straw, manure at 35 and 70 t ha-1 every 3 years and cattle slurry at 60 m3 ha-1 every 3 years) and mineral fertilizer (four doses nitrogen) are tested in Changins since 1976. This study analyses their long-term effect on organic, chemical and biological soil properties. After 34 years of trial, when crops receive optimal nitrogen fertilizer, the soil organic matter (SOM) content decreases 0,50 g/100 g of soil for the treatment «mineral fertilizer», 0,20 g/100 g for the treatments «greenmanure» and «straws» and 0,18 g/100 g for the treatments «manure 35 t ha-1 every 3 years» and «slurry 60 m3 ha-1 every 3 years». Only the treatment «manure 70 t ha-1 every 3 years» shows an increase in the SOM content of 0,15 g/100 g. Organic fertilizers do not significantly affect the main soil chemical properties, except for trace element contents. The treatments receiving manure and cattle slurry present higher amounts of copper, iron, zinc and manganese extractable in ammonium acetate EDTA than the control «mineral fertilizer». Organic fertilizers have also a positive significant effect on the activity and microbial biomass and seems to change the composition of this last.
Long-Term Effect of Organic Fertilizers on Crop Yield and Nitrogen Fertilization
Consequences of the use of different organic fertilizers (green manure, cereal straw, manure at 35 and 70 t ha-1 every 3 years and cattle slurry at 60 m3 ha-1 every 3 years) and mineral fertilizer (four doses nitrogen) are tested in Changins since 1976. This study analyses the long-term effect (34 years) on crop yield, the need for nitrogen fertilizer and the stock of mineral nitrogen (N) in the soil. When N is not limiting, organic fertilizers have different effects on grain yield. The year of organic input and the subsequent years, manure and slurry increase yields compared to the control without organic fertilizer, while green manure and systematic restitution of the cereal straw decrease it. However, on average over the past 34 years, these effects remain weak. On the contrary, when nitrogen is limiting, all forms of organic fertilizers have a positive long term effect on crop yields. The direct effect of organic fertilizer (first year of field application) may be positive or negative. The non fertilized green manure increases the need for nitrogen fertilizer during the year of its destruction but reduces it the following year. When fertilized with 60 kg N ha-1, it decreases the need for nitrogen fertilizer the year of its destruction as well as the following year. The fertilizing value of the cereal straw is negligible. Manure and slurry reduce significantly the need for N fertilizer on the three years following the application. When the fertilizer value of manure is not taken into account, the stock of mineral N in the soil present at harvest was higher in treatments with manure than in the control without organic fertilizer.
Potential for Drip Irrigation in Potato Production Under Changing Climatic Conditions
From 2008 to 2010 Agroscope Reckenholz-Tänikon Research Station ART examined the effectiveness of drip irrigation with the potato varieties Agria and Charlotte. Irrigation hoses were laid out between the rows or in each ridge of the furrow with an identical water supply. Only in 2008 there was a tendency for the gross yields produced by the irrigated methods to be higher. In 2008 and 2009, the Agria variety produced 12 to 16 per cent higher marketable yields with the irrigated methods. The percentage yield of oversized tubers (>70 mm) was the lowest in all three years of the trial with ridge irrigation. With irrigation, Agria's yield share in ware size rose by 2 to 9 absolute per cent in all the years of the trial. With the Charlotte variety, no effects of irrigation were noted on the percentage of ware size tubers. In two of the three years, the irrigated tubers of both varieties displayed a higher starch content. Irrigated tubers showed a higher infestation rate with powdery scab, but a lower infestation rate with common scab in netted, deep pitted and raised form respectively than non-irrigated tubers. Drip irrigation is a water- and energy-saving method for future yield and quality assurance in potato production.
Potassium Response and Requirement in Crops Grown in Vertisols: Experiences from Long-Term Fertiliser Experiment
Long-term fertilizer experiments (LTFE) were initiated with the aims to monitor the response of crops to nutrient in different soils and cropping systems to sustain productivity and food security of the country. The results generated over the years in LTFE, it indicate the responses to applied K in the soils, which were earlier considered rich in K. So to assess the response of crop to applied K, the data generated over the years were examined for K response. The results revealed that at Jabalpur gradual response to potassium was seen since inception of the experiment in soybean. However, in case of wheat response to applied K was observed since inception with a magnitude higher than the soybean. At Akola both sorghum and wheat showed responses to applied K, which increased with time in-spite of available K content more than the yard sticks prescribed for K. Analysis of soil K status revealed that absence of K in fertilizer schedule resulted decline in K status at the rate 2.1 to 9.7 kg ha-1 and addition of P accelerated the mining of K. Decline in available K status was arrested with the addition of K and some cases led to increase in available K form. Thus results indicate the need to modify or raise the K limits for rating the Vertisols as high and accordingly K recommendation be made in Vertisols.
Economics of Potassium Fertiliser Application in Rice, Wheat and Maize Grown in the Indo-Gangetic Plains
Potassium (K) fertilizer cost has increased considerably over the past three years. The sharp increase in price has raised doubts about the profitability of potassium application in cereals where the Minimum Support Prices (MSP) is low. On-farm K response studies in rice, wheat and maize, spread across the Indo-Gangetic Plains, highlighted that grain yield response to fertilizer K is highly variable and is influenced by soil, crop and management factors. Average yield losses in rice, wheat and maize in farmers' fields due to K-omission were 622, 715 and 700 kg/ha, respectively. This suggests that skipping application of K in the three cereal crops will cause variable yield and economic loss to the farmers of the region and will affect overall cereal production in the country. The return on investment of applied potassium in rice, wheat and maize were R.S. 5.5, 4.4 and 3.2 respectively per rupee invested on K. Economic assessment based on projected cost of K fertilizer and projected MSP of the cereals also showed favourable return on investment for K fertilizer. Considering the high variability in K response, blanket K recommendations would most likely lead to economic loss for farmers due to under or over application in most cases. A site specific potassium management strategy, based on the expected crop response to K at a location, would improve yield and profitability of cereal farming.
Flow and Deformation Behavior at the Microscale of Soils from Several Long-Term Potassium Fertilization Trials in Germany
The effect of K fertilization on microstructural soil stability is rarely analyzed until now although the ambiguous impact on bulk soil structure was reported quite often, e.g., with regard to higher erodibility on the one hand and higher water storage on the other. Soil material from different long-term fertilization trials in Germany was examined rheologically by means of an amplitude sweep test where the samples were subjected to oscillating shearing with increasing deflection. The resulting shear stress was recorded, and the maximum stress denoted the maximum shear strength of the sample. Results showed an ambiguous influence of K which depends strongly on the soil properties. On the one hand, an increased ion concentration in the soil solution leads to increasing attractive forces as defined by the DLVO theory and therefore higher shear resistance. With increasing desiccation, K+ like other salts can precipitate at the contact areas between particles and lead to cementation. On the other hand, K+ as a monovalent ion impedes covalent and ionic bonding between clay minerals which holds true for most of the examined soil types while only sandy soils showed an increase in soil strength due to K fertilization. Potassium depletion further resulted in increased interaction of fertilization with other impact factors, e.g., climate and soil properties. Thus, the destabilizing effect of K+ was more pronounced under liming as without liming. Subsequent modeling with selected soil parameters confirmed the high influence of matric potential. The modeling also revealed the interactions with other soil parameters, e.g., pH, oxides, texture, exchangeable cations as well as lack or surplus of K in relation to recommended K content. In conclusion, microstructural stability of soil depends on several soil parameters and requires the inclusion of many chemical and physical soil properties.
Critical Carbon Inputs to Maintain Soil Organic Carbon Stocks under Long-Term Finger Millet (Eleusine coracana [L.] Gaertn.) Cropping on Alfisols in Semiarid Tropical India
Enrichment of soil organic carbon (SOC) stocks through sequestration of atmospheric CO2 in agricultural soils is important because of its impacts on adaptation to and mitigation of climate change while also improving crop productivity and sustainability. In a long-term fertility experiment carried out over 27 y under semiarid climatic condition, we evaluated the impact of crop-residue C inputs through rainfed fingermillet (Eleusine coracana [L.] Gaertn.) cropping, fertilization, and manuring on crop yield sustainability and SOC sequestration in a Alfisol soil profile up to a depth of 1 m and also derived the critical value of C inputs for maintenance of SOC. Five treatments, viz., control, farmyard manure (FYM) 10 Mg ha–1, recommended dose of NPK (50 : 50 : 25 kg N, P2O5, K2O ha–1), FYM 10 Mg ha–1 + 50% recommended dose of NPK, and FYM 10 Mg ha–1 + 100% recommended dose of NPK imposed in a randomized block design replicated four times. Application of FYM alone or together with mineral fertilizer resulted in a higher C input and consequently built up a higher C stock. After 27 y, higher profile SOC stock (85.7 Mg ha–1), C build up (35.0%), and C sequestration (15.4 Mg C ha–1) was observed with the application of 10 Mg FYM ha–1 along with recommended dose of mineral fertilizer and these were positively correlated with cumulative C input and well reflected in sustainable yield index (SYI). For sustenance of SOC level (zero change due to cropping) a minimum quantity of 1.13 Mg C is required to be added per hectare per annum as inputs. While the control lost C, the application of mineral fertilizer served to maintain the priori C stock. Thus, the application of FYM increased the C stock, an effect which was even enhanced by additional amendment of mineral fertilizer. We conclude that organic amendments contribute to C sequestration counteracting climate change and at the same time improve soil fertility in the semiarid regions of India resulting in higher and more stable yields.
Assessment of Soil Phosphorus and Potassium following Real Time Kinematic-Guided Broadcast and Deep-Band Placement in Strip-Till and No-Till
Fertilizer placement may cause non-uniform nutrient distribution in the soil, making it difficult to determine whole-field fertility by traditional sampling strategies. Our objectives were to determine P and K distribution after repeated applications in no-till and strip-till soils and to develop improved sampling procedures to estimate soil P and K levels on a corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation with crops planted at 76-cm row spacing. Three trials near Pesotum, IL, received blends of 0–0, 22–42, 33–62, 44–83, 55–104, 66–125, and 77–145 kg P–K ha−1 in fall 2007 and 2009 before corn planting. Applications were broadcast-applied in no-till (NTBC) and strip-till (STBC) and deep-banded in strip-till (STDB) 15 cm below the surface in the crop row (IR) using real-time kinematic (RTK) satellite navigation. Every year soil P and K was measured at 10-cm increments to a 30-cm depth at 0, 19, 38, and 57 cm from the IR. Subsurface banding reduced P and K levels in the surface and increased them at the point of application, or deeper with the highest rate, while broadcast applications increased surface levels. Soil-surface K levels were greater at IR likely because of K leaching from senescing standing crops. Soil-test results indicated no need to adjust fertilizer rate based on tillage or fertilizer placement. A sampling ratio of 1:3 IR to between the crop rows (BR) seemed adequate to estimate soil fertility across a wide range of P- and K-fertilizer rates and soil test levels where the location of the fertilizer band or planting row is maintained constant.
Distribution of Soybean Roots, Soil Water, Phosphorus and Potassium Concentrations with Broadcast and Subsurface-Band Fertilization
In conservation tillage, fertilizer placement is designed to improve nutrient availability. Our objective was to determine the effect of tillage (no-till and strip-till) and P and K rate and placement on the distribution of soybean [Glycine max (L.) Merr.] roots and on water, P, and K levels in soil. A 3-yr field experiment was conducted near Urbana, IL, with soybean following corn (Zea mays L.). Rates of 0–0, 36–0, 0–168, and 36–168 kg P–K ha−1 yr−1 were applied as no-till/broadcast (NTBC), no-till/deep band (15 cm beneath the planted row) (NTDB), and strip-till/deep band (STDB). Roots and soil water, P, and K levels were measured periodically at in-row (IR) and between-rows (BR) positions at 0- to 5-, 5- to 10-, 10- to 20-, and 20- to 40-cm depths. Deep banding increased P and K soil test levels beneath the row and lowered soil surface test-values compared to broadcast applications, but had no effect on root distribution. Compared to NTBC and NTDB, STDB had a 20% increase in soil water content during the seed-fill period at BR within the top 10 cm of soil where greatest apparent nutrient uptake (estimated by changes in soil-test levels) occurred. Within that zone, NTBC produced and maintained a larger root system than STDB. However, STDB had 23% greater P and 30% greater K accumulation in shoots and also greater apparent nutrient uptake and greater apparent nutrient uptake rate per unit of root surface area. The results indicate that STDB provides overall better soil conditions for P and K uptake compared to the NTBC and NTDB systems.
Alfalfa Yield Components and Soil Potassium Depletion as Affected by Potassium Fertilization
Potassium fertilization recommendations for alfalfa (Medicago sativa L.) vary depending on the area of production, soil levels, and crop management. The objectives of this study were to determine the impact of K fertilization on irrigated alfalfa yield, yield components, and soil exchangeable K (Ke) values in a Mediterranean climate. A field experiment was conducted during a period of 4 yr (2002–2006) in Spain, on a soil with moderate levels of Ke (161 mg K kg−1). The treatments applied were five annual rates of K (0, 100, 200, 300, and 400 kg K ha−1). Total 4-yr dry matter (DM) yields averaged 74.9 Mg ha−1 without differences between K fertilizer rates, although the unfertilized control produced the lowest DM yields. The 4-yr crop uptake of K reached 1738 kg ha−1 with the application of 400 kg K ha−1 yr−1, and 756 kg K ha−1 for the 0 K fertilization. The removal was greater than the K applied. The results suggest that large amounts of K should not be applied to alfalfa because the crop uses excess K without increasing yield. Soil Ke concentrations decreased every year for all K rates except for the highest treatment of 400 kg K ha−1 yr−1. Lack of K fertilization did not affect stand density but the shoot weight was the yield component most closely related to K fertilization.
June 2012
English