IPI International Potash Institute
IPI International Potash Institute

K in the Literature: e-ifc No. 15, March 2008

K in the Literature

Evaluation of Zone Soil Sampling Approaches for Phosphorus and Potassium Based on Corn and Soybean Response to Fertilization. Sawchik, J., and A.P. Mallarino.
Agron. J. 99:1564-1578 (2007).

Soil sampling approaches have been compared based on soil-test variation. This study evaluated sampling approaches for P and K based on yield response to fertilization. Strip trials were established on four fields for P and three fields for K managed with corn (Zea mays L.) and soybean (Glycine max L. Merr.) rotations and evaluated 3 or 4 yr (27 site-years). Treatments replicated three to four times were fertilizer and no fertilizer application. Soil test results from a dense grid point sampling (DG) approach (0.08 to 0.27 ha) were used to simulate six approaches: (i) 1.0-ha grid cells (GC), and zones delineated based on (ii) soil series from digitized survey maps (SMZ); (iii) elevation (EZ); (iv) apparent soil electrical conductivity, ECa (ECZ); (v) EZ and ECZ (EECZ); and (vi) EZ, ECZ, and slope (EECSZ). Grain yield monitors, global positioning systems (GPS), and geographical information systems (GIS) were used to describe crop responses. Estimates of soil-test variation were largest for DG, intermediate for GC, and less for other approaches. Crops responded (P # 0.05) to fertilization in 20 site-years. Sampling approaches DG, GC, EZ, EECZ or EECSZ, ECZ, and SMZ identified a differential within-field yield response in 16, 8, 5, 3, 2, and 2 site-years, respectively. Differential yield responses seldom were explained by zone-mean soil-test values. Zone approaches often identified areas with different yield levels but were less effective than DG or GC at describing within-field variation of soil tests and yield response to fertilization. Zone approaches may be more effective in fields with shorter fertilization histories or soils with more contrast in properties.

Available 'K' Reserve of Two Major Crop Growing Regions (Alluvial and Shrink-Swell Soils) in India. Bhattacharyya, T., D.K. Pal, P. Chandran, S.K. Ray, S.L. Durge, C. Mandal, B. Telpande, and S.P. Wani.
Indian J. of Fertilizers 3:41.

The crop removal of K often equals or exceeds that of N. Under intensive cropping with high yielding varieties and imparity in nutrient use, K from soils getting depleted is evident from number of field experiments conducted across the county under the All India Coordinated Research Projects (AICRP) of The Indian Council of Agricultural Research (ICAR). The K is thus recognised as deficient element after N and P in Indian soils. The K fertilisers in India are mostly imported and since the gap between removal of K and its application to crop is widening, it is all the more important that the country makes the best use of them. To make such initiative successful, knowledge of K reserve in soils and periodic monitoring of changes in K status should form an essential part of such programme.

Foliar Diagnosis in the Orchard: Review of a 20 Years Study. Neyroud, J.A., S. Amiguet, G. Andrey, and Ch. Evequoz.
Revue suisse viticulture arboriculture horticulture 39:307-313 (2008), French.

This study presents a review of experiments made during 20 years with the foliar diagnosis method. Leaves samples of apricot, cherry, pear and apple trees have been collected at prescribed dates on healthy and productive orchards and analysed for their N, P, K, Mg and Ca-contents. Reference values were calculated according to average contents and statistical distributions of the results. In some cases, specific reference values had to be defined for some varieties, nutrient elements or years. Any other sample can then be analysed and compared to the proper reference values; differences from reference values are interpreted in terms of nutrient availability, equilibrium in nutrient uptake and tree vigour. Results obtained so far confirm the interest of the foliar diagnosis approach; this method might be further improved by a more precise definition of sampling time and by a more elaborate evaluation of nutrient contents and ratios, as realized in the DRIS model.

Agroscope Research Programs. Hilber, U., U. Bütikofer, H.P. Bachmann, Ch. Flury, and S. Pfefferli.
Revue Suisse d'àgriculture 39:271-276 (2007), French.

The three Agroscope research stations, Changins-Wädenswil ACW, Liebefeld-Posieux ALP and Reckenholz-Tänikon ART, will jointly carry out three multidisciplinary research programs during the period 2008-2011.

The "ProfiCrops" program aims at developing, preparing, evaluating and exchanging information in order to ensure a future for Swiss crop production in a largely liberalized market and to reinforce the confidence of consumers in Swiss products.

"NutriScope" aims at optimizing parameters determining quality, safety and health along the food chain, from "farm to fork", in order to offer consumers maximum value for money. Work will concentrate on the economically important food-stuffs manufactured from raw materials of Swiss agriculture.

The "AgriMontana" program is based on the idea that mountain areas can profit from a sustainable development while at the same time respond to the requirements of the local population and the whole of the social structure in mountain areas. Principles of action as well as political measures will have to be elaborated in this direction. Decision-making aids will be developed for the regional players along with a policy ensuring the sustainable development of mountain areas.

These research programs have a limited duration with clearly defined objectives, have a multidisciplinary orientation, and work in partnership with the customers who directly use and apply the research results. The creation of networks will allow us to bring together paramount know-how which will make it possible to answer essential questions in agriculture.

Effects of Suboptimal Fertilization on Arable Crops. Flisch, R., R.M. Hausherr, and E. Brack.
Revue Suisse d'àgriculture 40:11-16 (2008), French.

The production of high yields and adequate product quality requires a sufficient and balanced nutrients supply of the soil. The field trial, conducted since 1989 for purpose of demonstration, shows both the impact of different fertilizer forms (organic and mineral fertilizer) and the effects of an unbalanced fertilization. No differences in yield and product quality have been observed between the treatments "cattle slurry" and "mineral fertilizer", both well adapted to the nutrient demand of the crops. But the annual application of 250 dt/ha of farmyard manure decreased crop yield and product quality, due to the low availability of nitrogen to the crops and the low content of potash. The lack of a single nutrient element (N, P or K) in the mineral treatments affected crop yield, nutrient contents in crops and soil negatively already after few years. All crops have revealed deficiency symptoms of N, P or K in these treatments.

Comparison of No-Tillage and Conventional Plough Tillage: a Synthesis. Sturny, W.G., A. Chervet, C. Maurer-Troxler, L. Ramseier, M. M.
Revue Suisse d'àgriculture 39:249-254 (2008), French.

No-tillage and conventional plough tillage have been compared since 1994 in a crop rotation without fallow period and with mineral fertilizer only, in the long-term field trial "Oberacker" at the Inforama Ruetti in Zollikofen (Switzerland) on a slightly humic sandy loam deep and nutrient-rich soil.

Results obtained so far show continuous no-tillage of long duration to be an alternative to traditional plough tillage: no-tillage is ready for agronomical practice, leads to a biologically active soil of stable structure and thus of high load capacity, reduces risk of soil erosion, number of vehicle crossings and consumption of fuel and presents an overall more favourable life cycle assessment. After a seven-year conversion period, slightly higher plant yields of comparable quality were obtained in no-tillage, due to a better soil water preservation and continual supply to plant roots, as well as to a higher N-efficiency. Both cropping systems only received about 60% of the standard amounts of N-fertilizer.

Both systems shall be tested further and optimised for environmental sustainability and energy consumption by introducing more legume crops, ammonium-based N-fertilizer, and by reducing glyphosate application in no-tillage and tillage intensity in conventional plough tillage.

Emerging Nutrient Deficiencies in Different Soil Types under Rainfed Production Systems of India. Srinivasarao, Ch., and K.P.R. Vittal.
Indian J. of Fertilizers 3:37.

Soil samples from twenty one locations of the All India Coordinated Research Project for Dryland Agriculture (AICRPDA) were characterized for organic carbon and availability of nutrients such as nitrogen, phosphorus, potassium, sulphur, Ca, Mg, Zn, Fe, Mn, Cu and B. These twenty one locations cover agro-ecological regions from 2.3 to 12.3, semi-arid, arid and sub-humid climate, soils of Vertisols, Vertic sup-groups, Alfisols, Inceptisols and Aridisols. Rainfall ranged from 412 to 1378 mm among locations. Various physico-chemical properties of 21 profiles indicated the most of the locations were low in organic carbon showing less than 0.5% organic C. Clay content varied widely amoung soil types. Low organic matter in these soils is one of the important factors contributing to low soil fertility. Except few locations, most of the soils were low in available N. Available P varied from low to very high. Available K and sulphur varied from low to high. Available Zn was below critical limit in Rajkot, Anatapur, Rewa, Akola, Bellary, Bijapur and Solapur, Agra, S.K. Nagar, Arjia, Hoshiarpur and Rakh Dhiansar. Iron is deficient in Rajkot, Bellary and Bijapur. Surface layers of several profiles were deficient in available Ca (<1.5 me 100g1) such as Phulbani, Anantapur, S.K. Nagar and Bangalore. Surface layers of soils at Phulbani, Ranchi, Anantapur, Agra, Hisar, S.K. Nagar, Bangalore, Arjia, Hoshiarpur and Rakh Dhiansar were Mg deficient (<1.0 me 100g1). Out of 21 locations, 11 are boron deficient. Except Indore, all other soils were multinutrient deficient. Results suggest that dryland soils are multinutrient deficient and proper nutrient management strategies are needed even in dryland agriculture along with soil water conservation practices.

Effect of Irrigation and Potassium on the Yield and Yield Components of Carrot. Islam, M.M., R. Sen, S.A. Mallik, and M.S. Khan.
Bangladesh J. Agric. and Environ. 2006, 2:9-15.

A field trial was conducted in Grey Terrace Soil (Albaquepts) of Joydebpur to study the effect of different levels of irrigation and potassium on the yield and yield components of carrot during the Rabi seasons of 2000-01 and 2001-02. Sixteen treatment combinations comprising 4 levels each of irrigations [I0 = no irrigation, I1 = one irrigation at 20 days after sowing (DAS), I2 = one irrigation at 40 DAS and I3 = two irrigations each at 20 and 40 DAS] and potassium (F0 = 0, F1 = 75 kg, F2 = 100 kg and F3 = 125 kg K/ha) were tested in randomized complete block design with three replications. Irrigation and potassium alone and in combination influenced the yield and yield contributing characters. The highest root yield (19.0 t/ha in 2000-01 and 21.0 t/ha in 2001-02) was recorded from two irrigations each at 20 and 40 DAS with 125 kg K/ha (I3F3). Total water use by the crop varied from 13.61 to 18.74 cm in 2000-01 and 12.60 to 19.58 cm in 2001-02. The highest water use efficiency (1127 kg/ha/cm in 2000-01 and 1113 kg/ha/cm in 2001-02) was recorded from I2F3 treatment. Economic analysis showed that two irrigations with 125 kg K/ha (I3F3) gave the highest gross margin Tk. 1,47,840/ha and the highest marginal rate of return (4,852%) was obtained from two irrigations with 75 kg K/ha (I3F1) treatment.

Read on:

  • Farming A Climate Change Solution.
    This paper from ECOS, CSIRO Australia explains why farmers have a golden opportunity for reducing GHG with practices that accelerate carbon sequestration in soils. The results in this paper show that perennial grasses and tagasaste (a fast growing, perennial, leguminous shrub) were sequestering 7 mt/ha of CO2 per year more than traditional annual pastures. Read the full paper on
    For more K literature go to www.ipipotash.org/literature
    Note: All abstracts in this section are published with permission from the original publisher.
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