The Iowa soil-test interpretations and fertilizer recommendations for phosphorus (P) and potassium (K) were last updated in 1996 and 1999. The 1996 update involved the most important changes compared with previous recommendations. New soil-test P and K interpretation classes (very low, low, optimum, high, and very high) were developed to classify soil-test values into two sets corresponding to ...

Tomato  (L.ycopersicon esculentum  Mill.) cv. Rio Grande  seedlings were nutritionally conditioned with solutions complete fertilizer N(60% NO3+40% NH4)-P-K (20-20-20) , N(30%NO3+70% NH4)-P-K (15-5-30) , the first two week   N(60% NO3+40% NH4)-P-K (20-20-20) and later two week  N(30%NO3+70% NH4)-P-K...

Narrow-row soybean [Glycine max (L.) Merr.] production in corn [Zea mays L.]–soybean rotations results in various distances of soybean rows from previous corn rows, yet little is known about soybean responses to proximity to prior corn rows in no-till systems. The objective of this study was to evaluate the impacts of preceding corn rows on potassium (K) nutrition and yield of subsequent no-til...

Effect of different nitrogenous fertilizers on the growth and yield of three years old tea (Camellia sinensis L) plants was investigated at National Tea Research Institute, Shinkiari, (Mansehra) during 2005-06. The nitrogenous fertilizers used were ammonium sulphate, calcium ammonium nitrate, urea and nitrophos along with control receiving no fertilizer. All the nitrogenous fertilizers were app...

In classical aquaponics (coupled aquaponic systems, 1-loop systems) the production of fish in recirculating aquaculture systems (RAS) and plants in hydroponics are combined in a single loop, entailing systemic compromises on the optimal production parameters (e.g. pH). Recently presented decoupled aquaponics (2-loop systems) have been awarded for eliminating major bottlenecks. In a pilot study,...

An alternative method for fertilizer spread pattern determination was developed based on predicting where individual fertilizer particles land on the ground, in contrast to the traditional method of collecting the particles in bins (ASAE Standard S341.2). A small broadcast granular fertilizer spreader (Lowery 300) was equipped with an optical sensor designed to measure the velocity and diameter...

Nitrogen utilization by corn (Zea mays L.) is influenced by the form of inorganic N present in the root zone. A field experiment was conducted on Enon sandy loam (fine, mixed, thermic Ultic Hapludalf) to determine N use efficiency and its partitioning in various plant parts of corn. Ammonium nitrate labeled either as NH4-N or NO3-N and applied at 50, 100, or 200 kg N ha" was evaluated. Microplo...

The commodity market super-cycle and food price crisis have been associated with rampant food insecurity and the Arab spring. A multitude of factors were identified as culprits for excessive volatility on the commodity markets. However, as it regards fertilizers, a clear attribution of market drivers explaining the emergence of extreme price events is still missing. In this paper, we provide a ...

Ionomics is the study of elemental accumulation in living organisms using high-throughput elemental profiling. In the present study, we examined the ionomic responses to nutrient deficiency in maize grown in the field in long-term fertilizer trials. Furthermore, the available elements in the field soils were analyzed to investigate their changes under long-term fertilizer treatment and the iono...

Minimizing runoff losses from grasslands may benefit the producer and abate potential eutrophication of aquatic systems. This study was conducted to evaluate the effects of fertilizer source and soil aeration on the volume and quality of runoff from grassed plots. Sixteen tall fescue [Festuca arundinacea Schreb.]–bermudagrass [Cynodon dactylon L.] plots were established on Altavista sandy-loam ...