Biochar as agricultural soil amendment to improve soil physico-chemical properties, crop productivity and sustainable soil fertility management is a well-known practice. A field experiment was conducted to evaluate the effect of biochar on growth and yield components of carrot and selected soil physic-chemical properties. The study was carried by employing a randomized complete block design with factorial arrangement of four level of biochar (0, 4, 8 and 12 tons ha-1) and four level of Nitrogen/Phosphorus (N/P) fertilizer rate (0/0, 60/10, 90/15 and 120/20 kg ha-1) with four replications. Biochar significantly influenced physico-chemical properties of soils, such as bulk density, total porosity, pH, EC, SOC, TN, Av. P and CEC respectively, as compared to control. The results revealed substantial responses to biochar and N/P fertilization on growth and yield components of carrot with increasing level of biochar and N/P fertilizer rate. None of the others yield parameters were significantly affected by the interaction of two factors. From the present study, it can be concluded that dung cake biochar should be applied to enhance and improve soil physical and chemical properties for favourable plant growth.

Field experiments were carried out during the dry seasons in (2012-2013 and 2013-2014) to study the impact of Integrated Nutrient Management on some soil properties and nutrients uptake by red onion (Allium cepa L.) in Moda, Michika, Adamawa state, Nigeria. Soil samples were randomly collected and analysed for pH, EC, organic carbon, organic matter, total nitrogen, available phosphorus before and at the completion of the experiment. Total nitrogen, phosphorus and potassium contents of the onion bulbs were determined. There was an improvement in the fertility status of the soil as a consequence of integrated nutrient management. Combined organic and inorganic fertilizer application influenced the uptake of nitrogen, phosphorus and potassium by red onion. The highest nitrogen, phosphorous and potassium uptake by onions of 0.76, 43.82 and 2.42kgha-1 occurred when all treatments were combined. Uptake of N and K increased as treatment level increased. The P uptake was highest at lower treatment levels and could be linked to sufficiency of indigenous soil P for plant growth resulting in high P uptake with minimal addition of nutrient inputs. Integrated Nutrient Management could be adopted to improve soil fertility status and N, P and K uptake by red onions.

Şekerpancarı üretiminde verim ve kalite için azot (N) ve bor (B) gübrelemesi önemlidir. Fakat fazla azotlu (N) gübreler kalite parametreleri üzerinde olumsuz etkilere neden olmaktadır. Hayvan yemi olarak kullanılan şeker pancarı yapraklarında nitrat birikiminin artması da olumsuz etkilenen kalite parametrelerinden birisidir. Bu çalışmanın amacı, şeker pancarına farklı dozda azot ve bor uygulamasının bitki yapraklarında nitrat birikimi üzerine etkisini incelemektir. Çalışma, Kahramanmaraş ili Elbistan İlçesinde 2017 yılında B içeriği 0,56 mg kg-1 olan bir arazide yürütülmüştür. Deneme tesadüf blokları faktöriyel deneme desenine göre 3 tekerrürlü olarak kurulmuştur. Denemede 5 farklı N dozu (0, 9,18, 27, 36 kg N da-1) ve 4 farklı B dozu (0, 200, 400, 600 g B da-1) uygulanmıştır. Araştırmada temmuz, ağustos, eylül ve ekim aylarında yaprak örnekleri alınmıştır. Araştırma sonuçlarına göre N dozu arttıkça yaprakların nitrat içeriği istatistiksel olarak önemli derecede artmıştır. Bor uygulamasının yaprakların nitrat içeriği üzerine etkisi önemli bulunmamıştır. Hasat dönemine doğru yaprakların nitrat içeriği istatistiksel olarak önemli düzeyde azalmıştır. Sonuç olarak hasat sonrası şekerpancarı yapraklarının hayvan yemi olarak kullanması, nitrat bakımından hayvanlar için bir risk oluşturmamaktadır.

The aim of this study is to determine the stable isotope ratios of anchovy caught in the Black Sea and Marmara Sea. Stable carbon and nitrogen isotope ratios (δ13C, δ15N) of European anchovy (Engraulis encrasicolus) were estimated at four sampling sites (İğneada, İstanbul, Trabzon and Hopa) in the Black Sea and Marmara Sea (Turkey). δ13C and δ15N values of European anchovy ranged from -22.31 to -19.19 ‰ and from 3.81 to 12.79 ‰, while C/N ratios ranged from 2.01 to 6.21 in muscle tissue of European anchovy, respectively. İğneada station had more depleted δ13C values and more enriched δ15N values than other stations. This difference might be due to the terrestrial input and agricultural activities in this region.

The objective of the study was to determine the effect of three different biochars (Pin, Poplar, and Oak biochars), four different biochar doses (0, 1, 2, and 4%), and four different nitrogen rates (0, 70, 140, and 210 mg kg-1) on soil fertility, growth, and nutrient uptake of corn plants. The experiment was conducted in a greenhouse, and corn (Zea mays L.) was used as the test plant. The biochar types, biochar doses, and nitrogen rates significantly affected many soil and plant parameters. The highest leaf dry matter yield was obtained with a combination of the poplar biochar, 4% biochar dose, and 140 mg kg-1 N application.

Agronomic practices for the newly released shallot variety have not been conducted in Eastern Ethiopia. To assess the effect of nitrogen fertilizer rates and intra-row spacing, a field experiment was conducted in 2017 which consisted of seven rates of nitrogen (0, 25, 50, 75,100,125 and 150 kg N ha-1) and three intra-row spacing (7.5, 10 and 12.5 cm) in factorial combination and it was laid out in a RCBD with three replications. Results of the analysis revealed that all bulb yield and yield components of the variety were highly significantly influenced by the main effects of nitrogen fertilizer and intra-row spacing. Moreover, the interaction of nitrogen fertilizer and intra-row spacing significantly influenced days to maturity, plant height, and average bulb weight and bulb dry matter. The application of 125 kg N ha-1gave high total and marketable bulb yield advantage of 32.45% (13.89 t ha-1) and 40.8% (15.47 t ha-1), respectively over the control. Plants spaced at 7.5 cm had total and marketable bulb yield advantage of 35.94% (14.54 t ha-1) and 32.83% (12.42 t ha-1), respectively over plants spaced at 12.5 cm. Therefore, intra-row spacing of 7.5 cm with the application of 125 kg N ha-1 is used for optimum yield in the study area although further research should be needed to come up with conclusive recommendation.

The present study was carried out to evaluate the effect of nitrogen on growth and yield of chili (Capsicum annuum L.) under rooftop conditions. The single factorial experiments were laid out in Randomized Complete Block Design (RCBD) with three replications. Four levels of nitrogen N0: 0 kg N ha-1, N1: 90 kg N ha-1, N2: 110 kg N ha-1 and N3: 130 kg N ha-1 were used in this experiment. Growth and yield contributing parameters significantly influenced by different doses of nitrogenous fertilizers. The dose of N2 gave the highest plant height (80.97 cm) and most of the morphological parameters increased with increasing nitrogen levels up to N2. The treatment N3 gave the highest fruit length (4.93 cm), yield of fruits plant-1 (165.33 gm), average fruit yield plot-1 (0.66 kg), individual fruit weight (1.97 g) and average fruit yield (5.533 kgha-1). Based on the present results, it can be suggested that use of 130 kg N ha-1 increased plant growth and fruit yield of chili in rooftop garden.

Proper nitrogen (N) management is vital for gaining potential yield benefits of a variety. Adjusting transplanting time enables the plant taking benefit from natural conditions favorable for its growth. In light of these, an investigation was carried out in the Boro season at the Agronomy Field Laboratory, Bangladesh Agricultural University from November 2022 to April 2023 to investigate the impact of various transplanting dates and N levels on the yield of Nizershail rice. The study involved four dates of transplanting viz. 16 December, 31 December, 15 January, 30 January and four nitrogen (N) levels viz. 0, 50, 100 and 150% of the recommended dose (RD) of N from urea where the recommended dose was 90 kg urea per ha. The trial was replicated thrice using Randomized Complete Block Design (RCBD). Results showed that the tallest plant, the uppermost grains/panicle and 1000 grains weight were detected in 16 December transplanting and the maximum grain yield was observed in 31 December transplanting. For N, total tillers and effective tillers/hill, grains/panicle, the highest grain and straw yields were found from 100% RD of N and the highest panicle length and sterile spikelets/panicle were found from 150% RD of N. In interactions, the maximum effective tillers/ hill and straw yield were observed from 100% RD of N in combination with 15 January transplanting. The maximum 1000 grains weight and the grain yield were obtained from 100% RD of N in combination with 16 December transplanting. From the result, it may be assumed that to get the maximum yield of Nizershail rice in Boro season could be transplanted between 16 December to 15 January with 100% RD of N from urea.

In Ethiopia livestock feed shortage and soil acidity are serious problems. In recent years sweet lupins (white and blue species) were introduced as multipurpose crops in the country. However, there is no information about their nodulation potential. This study was conducted to evaluate nodulation potential of these sweet lupins and their effect on nitrogen (N) and phosphorous (P) content of the soil. Seven lupin varieties were evaluated using factorial arrangement (seven varieties * two inoculations) in a randomized complete block design in two locations for two years. The result showed that effect of inoculation and location was not significant (P > 0.05) on biomass, seed, nodule number and soil parameters. While the effect of variety was significant (P < 0.05) on nodule parameters. Its effect on dry biomass and seed yields was also significant in either of the years. Variety and year had no effect on soil N and P contents. In the first year, blue sweet lupin entries had the highest nodule number per plant, 222 nodules.  In the second year similar nodulation performance was observed among species and varieties. Soil N and P were not affected by varieties and inoculation. In addition to their yield advantage, compared to the sweet white entries, blue sweet lupin varieties had high potential in nodulation. Therefore, these introduced sweet blue lupins can be used as multipurpose crops in acidic soils of Ethiopia.