Study on Integrated Effect of Inorganic Fertilizers and Organic Manure on Available Nutrients, Yield and Nutrient Uptake in Scented Rice

Field experiments were conducted at the Instructional-cum-Research (ICR) Farm, Assam Agricultural University, Jorhat during the year 2017 and 2018 to study the integrated effect of inorganic fertilizers and organic manure on available nutrients, yield and nutrient uptake in scented rice. Before the test crop experiment, fertility gradient experiment was conducted by using kharif rice (cv. Ranjit) as an exhaust crop to create three fertility gradient strips. After harvesting the gradient crop, test crop experiment was conducted in the same field with scented rice (cv. Keteki joha) by superimposing 24 combination treatments consisting of five levels of N (0, 10, 20, 40 and 60 kg ha-1), four levels of P2O5 (0, 5, 10 and 20 kg ha-1), three levels of K2O (0, 10 and 20 kg ha-1) and three levels of vermicompost (0, 2 and 3 t ha-1) in each of these fertility gradient strips. Results show that application of integrated nutrient management approach brought about a positive influence on organic carbon, nutrient availability, crop yield and nutrients uptake by scented rice. Combined application of 60 kg N, 10 kg P2O5 and 10 kg K2O per hectare along with 3 tons of vermicompost per hectare resulted in the highest concentration of available NPK in soils, the highest crop yield and uptake of nitrogen, phosphorus and potassium by rice.

Soil test based fertilizer prescriptions under integrated plant nutrient management system for carrot in an Inceptisol

A field experiment was conducted at Agricultural Research Farm, Banaras Hindu University, Varanasi in an Inceptisol during rabi 2020-21 to develop a targeted yield equation for carrot crop. After developing three levels of fertility gradient with respect to available NPK in soil, the main experiment was conducted by taking carrot as a test crop. Initial soil data, carrot yield and NPK uptake by carrot crop were used for obtaining four important basic parameters, viz., nutrients required to produce a quintal of carrot roots (NR%), contribution of nutrients from fertilizers (CF%), contribution of nutrients from soil (CS%) and contribution of nutrients from organic matter (%C-OM). It was found that 0.65, 0.11 and 0.83 kg of N, P2O5 and K2O, respectively were required for producing one quintal carrot yield. The per cent contribution of nutrients from soil, fertilizer and FYM were 45.33, 65.91 and 67.26 for N; 58.45, 67.86 and 108.12 for P2O5 and 5.54, 3.35 and 10.53 for K2O, respectively. The ready reckoner for fertilizer doses with NPK alone and integrated use of NPK and FYM was also made using developed basic parameters for varying soil test values and desired yield targets of carrot yield.

Changes of ground vegetation after shelter wood cuttings in pine forests, the hemiboreal zone, Lithuania

Sustainable forestry plays an important role in applying forest management measures. In many forests, management is oriented towards closer natural forest processes. Silvicultural systems that retain some part of the trees in the stand, such as shelter wood cuttings have been introduced. The aim of the study was to evaluate the early changes of ground vegetation after shelter wood cuttings in sites of different soil fertility gradient in pine dominated stands on sandy soils in the European hemiboreal zone. The Scots pine stands in which first step of shelter wood cuttings was applied were investigated. The stands were selected in fresh (normal humidity) sites according to soil fertility gradient: very poor, poor and medium fertility soils. All mosses, lichens, herbaceous vegetation and dwarf shrubs were recorded, and projection cover was estimated in June - August. Ellenberg’s indicator figures were used to evaluate site conditions. In shelter wood cuttings (5-6-year-old) the number of species was higher in medium fertile sites than in very poor sites. After shelter wood cuttings the abundance of herbaceous species increased in all sites, while the abundance of mosses and lichens decreased. Within the first year after shelter wood cuttings, the abundance of Ericaceae species decreased, and abundance of Rosaceae and Poaceae species increased. Average Ellenberg’s indicator values showed that site conditions changed after shelter wood cuttings. The changes were more intensive in medium fertile sites than in poor sites. After shelter wood cuttings the richness and abundance of ground vegetation changed. The intensity of change differed in sites of certain soil fertility and was caused by alteration of site conditions, which were more homogenous in sites of the certain fertility in uncut stands than in cuttings. Key words: herbs, mosses, non-clear cuttings, vegetation

CoupModel (v6.0): an ecosystem model for coupled phosphorus, nitrogen, and carbon dynamics – evaluated against empirical data from a climatic and fertility gradient in Sweden

This study presents the integration of the phosphorus (P) cycle into CoupModel (v6.0, referred to as Coup-CNP). The extended Coup-CNP, which explicitly considers the symbiosis between soil microbes and plant roots, enables simulations of coupled carbon (C), nitrogen (N), and P dynamics for terrestrial ecosystems. The model was evaluated against observed forest growth and measured leaf C∕P, C∕N, and N∕P ratios in four managed forest regions in Sweden. The four regions form a climatic and fertility gradient from 64∘ N (northern Sweden) to 56∘ N (southern Sweden), with mean annual temperature varying from 0.7–7.1 ∘C and soil C∕N and C∕P ratios varying between 19.8–31.5 and 425–633, respectively. The growth of the southern forests was found to be P-limited, with harvested biomass representing the largest P losses over the studied rotation period. The simulated P budgets revealed that southern forests are losing P, while northern forests have balanced P budgets. Symbiotic fungi accounted for half of total plant P uptake across all four regions, which highlights the importance of fungal-tree interactions in Swedish forests. The results of a sensitivity analysis demonstrated that optimal forest growth occurs at a soil N∕P ratio between 15–20. A soil N∕P ratio above 15–20 will result in decreased soil C sequestration and P leaching, along with a significant increase in N leaching. The simulations showed that Coup-CNP could describe shifting from being mostly N-limited to mostly P-limited and vice versa. The potential P-limitation of terrestrial ecosystems highlights the need for biogeochemical ecosystem models to consider the P cycle. We conclude that the inclusion of the P cycle enabled the Coup-CNP to account for various feedback mechanisms that have a significant impact on ecosystem C sequestration and N leaching under climate change and/or elevated N deposition.

Evaluation of Fertilizer Doses for Kharif Brinjal (Solanum melongena L.) through Soil Test Crop Response Approach in Mollisols of Uttarakhand

A Field experiment was conducted at N. E. Borlaug Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar (Latitude 290N, Longitude 79030’ E and Altitude 243.84 m above MSL) during kharif season of 2018-19 in Mollisols of Uttarakhand, India for brinjal through Soil Test Crop Response (STCR) to recommend desired fertilizer nutrients. In the Initial phase of the investigation the artificially fertility gradient was setup to create heterogeneity in experimental soil for the test crop. Further, in second phase response of brinjal to selected combinations of three levels of FYM (0, 10 and 20 t ha-1), four levels of nitrogen (0, 60, 120 and 180 kg N ha-1), four levels of phosphorus (0, 30, 60 and 90 kg P2O5 ha-1) and four levels of potassium (0, 30, 60 and 90 kg K2O ha-1) in different soil fertility strips was also worked out in a Fractional Factorial Design (Latin Square type). Using the data of soil analysis, nutrient uptake and yield the basic data for fertilizer prescription were computed. Fertilizer adjustment equations were generated with the help of basic data. Fertilizer prescription equation helps in evaluating fertilizer requirement for kharif brinjal at different soil test values and yield targets as per farmers’ economic conditions. Before their use by soil testing laboratories/farmers, the equations must be verified at farmer’s field.

CoupModel (v6.0): an ecosystem model for coupled phosphorus, nitrogen and carbon dynamics – evaluated against empirical data from a climatic and fertility gradient in Sweden

This study presents the integration of the phosphorus (P) cycle into CoupModel (Coup-CNP). The extended Coup-CNP enables simulations of coupled carbon (C), nitrogen (N) and P dynamics for terrestrial ecosystems which explicitly consider mycorrhizal interactions. The model was evaluated against observed forest growth and measured leaf C/P, C/N and N/P ratios in four managed forest regions in Sweden. The four regions form a climatic and fertility gradient from 64° N in the North to 56° N in South Sweden with the mean annual temperature varying between 0.7–7.1 °C and the soil C/N and C/P ratios between 19.8–31.5 and 425–633, respectively. The growth of the southern forests was found to be P-limited, with harvested biomass representing the largest P loss over the studied rotation period. The simulated P budgets revealed that southern forests are losing P while northern forests are close to a steady state in P availability. Mycorrhizal fungi account for half of the total plant P uptake across all four regions, which highlights the importance of fungal-tree interactions in Swedish forests. Sensitivity analysis results demonstrated that the highest forest growth occurs at a soil N/P ratio of 15 to 20. A soil N/P ratio above 15–20 resulted in decreased soil C sequestration and total P leaching, but significantly increased N leaching. The development and evaluation of the new Coup-CNP model demonstrate that P fluxes need to be further considered in studies of how climate change will influence C turnover and ecosystem responses. We conclude that the potential P-limitation of terrestrial ecosystems highlights the need of a proper consideration of the P cycle in biogeochemical models. The inclusion of the P cycle is necessary in order to make models reliable tools for assessing long-term impacts of climate change and N deposition on C sequestration and N leaching.

Evaluation Of Soja Productivity (Imperial Variete And Canada) In Association With Maize (Bamboo Variete) In The Ecological Conditions Of Sustainable Use Of Sake / Nord Kivu

With a view to using land capital in an efficient and effective manner with a view to encouraging sustainable development in this ecological area of North Kivu; and to help minimize land-use conflicts, we have thought of establishing a combination of crops (soybean and maize) as a technique that can help maximize yields / ha and household income, while maintaining the fertility gradient of the soil. The effectiveness of Soybean-maize associations offers interesting prospects for improving the sustainability of production systems.The trial was arranged in randomized randomized blocks with 5 treatments and 3 replicates. For this study we used 2 soybean varieties that are: imperial and canada, with a variety of corn (bamboo).The arrangement of the association was of the type MBILI-MOJA which means two Soya lines intercepted by a corn line. The parameters studied were the phenological and productive parameters which are: survey rate, neck diameter, height at flowering, number of leaves per foot, average number of pods per plant for soybean, average number of seeds of soybean pod, percentage of pod burst, soybean biomass removal, number of ears per plant, weight of 100 soybean and corn seeds, plot production (in kg), yield per tonne per hectare and the LER.The GENSTAT descovery software allowed us to analyze the variance of our data and the averages were separated using the PPDS at the 5% threshold.The performance of the associations was as follows:Imperial: 1,6 L.E.R =, L.E.R> 1 (there is a productive advantage in this association with corn bamboo); Canada: 2,33 LER =, LER> 1 (there is a productive advantage in this association with bamboo maize.) In both cases, there is maintenance of biodiversity and soil fertility.with maize as the imperial variety, that of 2.33 by the performance of LER. Fertility of the soil has been maintained from this technique which promotes soil and atmospheric nitrogen which crops need for their growth and productivity. Keywords: Soybean, maize, Association, Development sustainability, LER, SAKE / North Kivu