Organic Inputs Research Articles

Productivity of Wheat Landraces in Rainfed and Irrigated Conditions under Conventional and Organic Input in a Semiarid Mediterranean Environment

Wheat landraces are locally adapted populations that are suitable for low-input agronomic management and constraining pedo-climatic conditions. The productivity of landraces under high-input and optimal conditions is usually lower than modern wheat varieties. The present study compared the response of Sicilian wheat landraces and modern varieties to organic management, including organic fertilization, and conventional management, including mineral fertilization and chemical weed control, under rainfed condition and supplementary irrigation in a field trial conducted on a xerofluvent soil in a semiarid Mediterranean climate. Modern varieties were on average more productive than landraces, although certain landraces achieved comparable yields, in particular under organic management. The increase in grain yield under conventional management in comparison with the organic management was higher for modern varieties than landraces. The loss of productivity in rainfed conditions was lower for landraces compared to modern varieties. The grain quality traits were similar between landraces and modern varieties and in both cases the conventional management led to an improvement of the traits. These findings highlight the resilience and adaptability of traditional wheat landraces to low-input agricultural systems and offer valuable insights into improving the sustainability and productivity of wheat production in Mediterranean environments.

Effect of Kappaphyscus alvarezii seaweed liquid extract on growth, yield and chemical constituents of Geranium (Pelargonium graveolens l’ Herit. ex Aiton)

The application of seaweed-based fertilizers is an important renewable resource and gaining considerable attention in the present scenario of agriculture and horticulture as organic nutrient input and growth promoters. The present study was conducted to examine the effect of seaweed liquid extract on growth, yield, and chemical constituents of the important aromatic plant geranium. The experiments were conducted in the CSIR-CIMAP, Research Center, Bengaluru (Karnataka, India) during the Rabi season of 2018–2019 and 2019–2020. The results of pooled data over two years revealed that application of Kappaphycus alvarezii seaweed liquid extract (KSWE) along with RDF at a concentration of 15% significantly improved the plant height (71.37 ± 0.69 cm), plant canopy (68.24 ± 1.60 cm), herb yield (42.71 ± 2.45 t ha−1year−1) and oil recovery (0.36 ± 0.02%) as compared over RDF. An account of 23.14% and 23.87% increase in herbage and essential oil yield was recorded over RDF. The functional relationship between herb and oil yield of geranium with different concentrations of seaweed extract applied at different crop stages was strongly correlated (r 2=0.97 and r 2=0.91, respectively). The chemical profile of essential oil reveals that higher amounts of linalool (7.5%) isomenthone (6.65%), geranial (1.29%), geranyl formate (3.81%), and the highest citronellol to geraniol (C:G ratio) ratio of 2.14 was noticed in the treatment which receives 15% KSWE along with RDF. The study clearly exhibits the notable benefits in the performance of geranium with the application of 15% of aqueous seaweed extract from Kappaphyscus alvarezii both in quantitative and qualitative terms.

Impact of bulky manures and fermented liquid formulations in enhancing the quality parameters of sweet pepper

Indigenous fermented liquid formulations (Panchagavya, Jeevamrut and Amritpani) are rich sources of beneficial microflora and fauna, vitamins, minerals and growth-promoting hormones. Small and marginal farmers of North-West Himalayan region popularly grow sweet pepper as commercial crop. Poultry manure and vermicompost are two cheap nutrient sources, popular among these growers. So, inorder to investigate the combined effect of these organic inputs, two-year field experiment with seven treatments and three replications; with randomized block design; comprised of 100, 90, 80, 70, 60, 50, 40 per cent recommended dose of nutrients (RDN) which was applied through vermicompost and poultry manure along with Panchagavya (5%), Jeevamrut (5%), Amritpani (5%) and plant growth promoting rhizobacteria which was isolated from experimental location, applied to all treatments, except T1; was carried out to study the response of these inputs on quality parameters of sweet pepper. Results revealed that treatment T2 that comprised of 90% RDN including Panchagavya, Jeevamrut, Amritpani and PGPR led to noticeably improvement in growth and quality parameters viz. chlorophyll-a (0.52 mg g−1), chlorophyll-b (0.73 mg g−1), ascorbic acid (29.47 mg 100 g−1), protein content (28.90%), capsaicin content (0.23 mg g−1), number of primary branches (8.20), average fruit weight (62 g), fruit yield (290.58 quintals ha−1), number of flowers per plant (24.97), leaf area index (4.73) and shelf life (6.03 days). Hence, it is concluded that the combined use of these inputs has the potential to enhance growth and quality characteristics of sweet pepper in achieving sustainable crop productivity.

Effect of Organic Nutrient Sources on Growth, Seed Yield and Seed Quality of Radish (Raphanus sativus L.) cv. Chinese Pink

Seed is the ultimate economic input in any crop production programme. Two field experiments were conducted to study the effect of organic inputs on seed production of radish at Organic Block of Department of Vegetable Science, Dr YS Parmar University of Horticulture and Forestry, Nauni, Solan (HP) during Rabi season of 2019-20 & 2020-21. Various combinations of organic and liquid manures were replicated thrice in the form of twelve treatments in Randomized Block Design (RBD) Factorial. The pooled data of two years revealed that treatment with Vermicompost @ 8 t/ha + Jeevamrit @ 10 per cent was rated as best treatment for majority of characters like days to 50 per cent initiation of bolting (61.00), days to 50 per cent flowering (93.33), number of primary branches per plant (11.13), plant height (171.50 cm), pod length (5.82 cm), number of seeds per pod (5.01), seed yield per plot (225.25 g) & hectare (417.13 kg) and seed quality parameters like 1000 seed weight (12.02 g), seed germination (97.03 %), seedling length (28.26 cm), seedling dry weight (8.87 mg), seed vigour index-I (2742.07) and seed vigour index-II (860.42). Vermicompost along with jeevamrit recorded 61.41 per cent increase in yield over control. Hence application of vermicompost @ 8 t/ha + jeevamrit @ 10 per cent can be recommended for getting higher seed yield and better growth for organic seed production of radish.

Organic geochemistry and 1D-basin modeling in the Taranaki Basin, New Zealand: Implications for deltaic-source rocks of the cenozoic oil and condensate reservoirs

The Taranaki Basin in New Zealand is an area of active exploration for oil and condensate. This research focuses on integrating geochemical characteristics and 1-D basin modeling to Late Cretaceous to Miocene source rock systems, along with oil and condensate data from fifty-seven wells in the Taranaki Basin. The geochemical study reveals that the oil and condensate samples were generated from clay-rich source rocks, containing mixed organic matter, with large amounts of terrestrial organic matter input. These source rocks were deposited in fluvial to fluvio-deltaic environments under oxic conditions. The presence of oleanane in both oil and condensate samples suggests that the source rocks had a significant terrestrial component and deposited during the Late Cretaceous to Cenozoic. Using various biomarker proxies, oil-source rock correlation along with 1-D basin modeling revealed that the oil and condensate were mainly derived from the Late Cretaceous Rakopi and Paleocene Farewell formations at different maturity stages. The oils were generated within the peak-mature oil window, while the condensates primarily resulted from the secondary cracking of oil taking place in the source rock within the gas generation window. This finding is consistent with the 1-D basin modeling results. The model shows that the Paleocene Farewell source rock has achieved the primary stage of oil generation (0.55–0.95 Easy %Ro), contributing to most of the discovered oils in the Cenozoic reservoir rocks. Meanwhile, the Late Cretaceous Rakopi source rock reached the gas window with a higher vitrinite reflectance of more than 1.30 Easy %Ro, indicating greater gas generation potential.

Distinct contributions of microbial and plant residues to SOC during ecosystem primary succession in a Tibetan glacier foreland

Soil organic carbon (SOC) rapidly accumulates during ecosystem primary succession in glacier foreland. This makes it an ideal model for studying soil carbon sequestration and stabilization, which are urgently needed to mitigate climate change. Here, we investigated SOC dynamics in the Kuoqionggangri glacier foreland on the Tibetan Plateau. The study area along a deglaciation chronosequence of 170-year comprising three ecosystem succession stages, including barren ground, herb steppe, and legume steppe. We quantified amino sugars, lignin phenols, and relative expression of genes associated with carbon degradation to assess the contributions of microbial and plant residues to SOC, and used FT-ICR mass spectroscopy to analyze the composition of dissolved organic matter. We found that herbal plant colonization increased SOC by enhancing ecosystem gross primary productivity, while subsequent legumes development decreased SOC, due to increased ecosystem respiration from labile organic carbon inputs. Plant residues were a greater contributor to SOC than microbial residues in the vegetated soils, but they were susceptible to microbial degradation compared to the more persistent and continuously accumulating microbial residues. Our findings revealed the organic carbon accumulation and stabilization process in early soil development, which provides mechanism insights into carbon sequestration during ecosystem restoration under climate change.

Partial replacement of inorganic fertilizer with organic inputs for enhanced nitrogen use efficiency, grain yield, and decreased nitrogen losses under rice-based systems of mid-latitudes

In the rice-based system of mid-latitudes, mineral nitrogen (N) fertilizer serves as the largest source of the N cycle due to an insufficient supply of N from organic sources causing higher N losses due to varying soil and environmental factors. However, aiming to improve soil organic matter (OM) and nutrients availability using the best environmentally, socially, and economically sustainable cultural and agronomic management practices are necessary. This study aimed to enhance nitrogen use efficiency (NUE) and grain yield in rice-based systems of mid-latitudes by partially replacing inorganic N fertilizer with organic inputs. A randomized complete block design (RCBD) was employed to evaluate the effects of sole mineral N fertilizer (urea) and its combinations with organic sources—farmyard manure (FYM) and poultry compost—on different elite green super rice (GSR) genotypes and were named as NUYT-1, NUYT-2, NUYT-3, NUYT-4, NUYT-5, and NUYT-6. The study was conducted during the 2022 and 2023 rice growing seasons at the Rice Research Program, Crop Sciences Institute (CSI), National Agricultural Research Centre (NARC), Islamabad, one of the mid-latitudes of Pakistan. The key objective was to determine the most effective N management strategy for optimizing plant growth, N content in soil and plants, and overall crop productivity. The results revealed that the combined application of poultry compost and mineral urea significantly enhanced soil and leaf N content (1.36 g kg− 1 and 3.06 mg cm− 2, respectively) and plant morphophysiological traits compared to sole urea application. Maximum shoot dry weight (SDW) and root dry weight (RDW) were observed in compost-applied treatment with the values of 77.62 g hill− 1 and 8.36 g hill− 1, respectively. The two-year mean data indicated that applying 150 kg N ha⁻1, with half provided by organic sources (10 tons ha⁻1 FYM or poultry compost) and the remainder by mineral urea, resulted in the highest N uptake, utilization, and plant productivity. Thus, integrated management of organic carbon sources and inorganic fertilizers may sustain the productivity of rice-based systems more eco-efficiently. Further research is recommended to explore root and shoot morphophysiological, molecular, and biochemical responses under varying N regimes, aiming to develop N-efficient rice varieties through advanced breeding programs.

Blue Carbon Assessment in the Salt Marshes of the Venice Lagoon: Dimensions, Variability and Influence of Storm‐Surge Regulation

AbstractSalt marshes are intertidal coastal ecosystems shaped by complex feedbacks between hydrodynamic, morphological, and biological processes. These crucial yet endangered environments provide a diverse range of ecosystem services but are globally subjected to high anthropogenic pressures, while being severely exposed to climate change impacts. The importance of salt marshes as “blue carbon” sinks, deriving from their primary production coupled with rapid surface accretion, has been increasingly recognized within the framework of climate mitigation strategies. However, large uncertainties remain in salt marsh carbon stock and sequestration estimation. In order to provide further knowledge in salt marsh carbon assessment and investigate marsh carbon pool response to management actions, we analyzed organic matter content in salt marsh soils of the Venice Lagoon (Italy) from 60 sediment cores to the depth of 1 m and estimated organic carbon stock and accumulation rates in different areas. Organic carbon stocks and accumulation rates were highly variable in different marshes, being affected by organic and inorganic inputs and preservation conditions. Our estimates suggest that the studied marshes store 17,108 ± 5,757 tons of carbon per square kilometer in top 1‐m of soil and can accumulate 85 ± 25 tons of carbon per square kilometer per year. However, flood regulation may reduce the annual marsh CO2 sequestration potential by more than 30%. Our results contribute valuable information for regional carbon assessments, reinforcing the need for integrated coastal management policies to preserve the ecosystem services of coastal environments, and underscore the importance of considering local variability and methodological variations.

Different patterns of bacterioplankton in response to inorganic and organic phosphorus inputs in freshwater lakes - a microcosmic study

Phosphorus (P) is a limiting factor in fresh waters and is also the main cause of water eutrophication and deterioration, However, the practical effect of elevated P level on bacterioplankton is less evaluated. In this study, we investigated the bacterioplankton in a 96 hours microcosm experiment with P additions in two forms (organic/inorganic P, OP/IP) and three levels (final conc., 0.040, 0.065 and 0.125 g/L), aiming to find out the response pattern of bacterioplankton in coping with the increasing P levels. Results showed a more dramatic change of water properties and bacterioplankton between P forms (OP and IP) than among the addition levels, and a more remarkable effect of OP addition than the IP. Both OP and IP treatments significantly decreased the water pH, dissolved oxygen (DO), Electrical Conductivity (EC), Nitrate Nitrogen (NO3--N) and Total Organic Carbon (TOC), and reduced the α-diversity of bacterioplankton and relative abundance of Cyanobacteria, but increased the abundance of Proteobacteria. The IP addition decreased Actinobacteria abundance (especially for HgcI) and showed higher denitrification potentials, while the OP addition depressed the Bateroidota and exhibited lowed methylotrophic functions, but such trends decreased with increasing addition concentrations. The network analysis showed that both IP and OP additions increased the proportion of positively correlated edges and reduced the network complexity and stability, but the OP network was more stable than the IP network. The study clarifies the response pattern of bacterioplankton to the P input with different forms and levels, and deepens our understanding of the eutrophication process, which provides a scientific basis for the management and control of freshwater lakes facing eutrophication.

Economic optimization of sustainable soil management: a Dutch case study

Soil quality is pivotal for crop productivity and the environmental quality of agricultural ecosystems. Achieving sufficient yearly income and long-term farm continuity are key goals for farmers, making sustainable soil management an economic challenge. Existing bio-economic models often inadequately address soil quality. In this study, we apply the novel FARManalytics model, which integrates chemical, physical, and biological indicators of soil quality indicator, quantitative rules on how these indicators respond to farmers’ production management over time, and an economic calculation framework that accurately calculates the contribution of production management decisions towards farm income. This is the first study applying this model on existing arable farms. FARManalytics optimizes crop rotation design, cover crops, manure and fertilizer application and crop residue management. Nine Dutch arable farms were analyzed with a high variation in farm size, soil type, and cultivated crops. First, we assessed farm differences in soil quality and farm economics. Second, we optimized production management to maximize farm income while meeting soil quality targets using farm-specific scenarios. Third, we explored the impact of recent policy measures to preserve water quality and to increase the contribution of local protein production. The results show that the case farms already perform well regarding soil quality, with 75% of the soil quality indicators above critical levels. The main soil quality bottlenecks are subsoil compaction and soil organic matter input. We show that even in front-runner farms, bio-economic modeling with FARManalytics substantially improves economic performance while increasing soil quality. We found that farm income could be increased by up to €704 ha−1 year−1 while meeting soil quality targets. Additionally, we show that to anticipate on stricter water quality regulation and market shift for protein crops, FARManalytics is able to provide alternative production management strategies that ensure the highest farm income while preserving soil quality for a set of heterogenous farms.

Exploring possibilities of broccoli (Brassica oleracea L. var. italica) production under organic management

Broccoli (Brassica oleracea L. var. italica) was introduced as part of the Indian government's efforts to diversify and modernize agriculture in the region. Its introduction has helped J&K farmers to increase their income through higher market prices and to gain access to new markets and trade opportunities. It being a nutrient-demanding crop, farmers use high doses of chemical fertilizers, pesticides and herbicides and if consumed as salad or half-boiled in many culinary dishes, these chemicals are likely to impact the health of consumers and affect the environment. Therefore, alternative usage to these chemicals using combinations of organic inputs was aimed at producing a healthy crop of broccoli. It was concluded that the application of FYM@ 25 t/ha as a basal dose in the presence of seedling dip treatment of biofertilizers (Azotobacter @ 0.5 kg/ha + Phosphate-Solubilizing Bacteria @l kg/ha + Potassium-Mobilizing Bacteria @ 750 ml/ha) along with the scheduled application of Neem oil +Baeuveria bassiana at 1, 3, 7 and 15 days of interval after disease symptoms was found superior in obtaining higher curd yield (109.57 q/ha) and seed yield (604.96 kg/ha).

Effect of Different Tillage and Organic Inputs on Soil Properties and Yield of Cotton on Vertisols

The present investigation was carried out at Research Farm, Department of Soil Science, Dr. PDKV, Akola during Kharif 2023-24 to study the effect of different tillage practices and organic inputs on soil properties and yield of cotton on Vertisols. Intensive tillage accelerates the loss of soil organic carbon (SOC) and reduces soil quality and yields, particularly in rainfed areas. This is further worsened by imbalanced fertilization and insufficient recycling of organic residues. Conservation tillage, when combined with organic inputs like FYM, vermicompost and phospho-compost, can help to restore soil structure, increase SOC and promote sustainable agricultural practices. The study aimed to assess the effect of different tillage practices and organic inputs on soil properties and on yield of cotton. The factorial randomized block design with two factors and four tillage treatments as factor A and four sources of manure as factor B were adopted. The treatments were composed of factor A consisting of four tillage operations [conventional tillage (T1), reduced tillage (T2), minimum tillage (T3) and zero tillage (T4)] and factor B consisting of organic manures such as farmyard manure (10 t ha-1) (M1), vermicompost (5 t ha-1) (M2), phospho-compost (5 t ha-1) (M3) and no manure (M4) replicated thrice. The results clearly indicated that conventional tillage resulted in the significantly highest seed cotton yield (14.10 ha-1), stalk yield (27.78 ha-1), total uptake of N (46.46 ha-1), P (7.86 ha-1) and K (33.05 ha-1) relative to other tillage practices examined. Among the organic manure treatments the highest seed cotton yield (11.21 ha-1), stalk yield (21.95 ha-1), total N (37.27 ha-1), P (6.57 ha-1) and K (31.25 ha-1) uptake by cotton was observed with phospho-compost application. Based on the observed results, it was notable that the available soil N, P and K were significantly influenced by the distinct tillage practices and organic manures. Among the tillage practices, the highest content of available soil N (182.14 kg ha-1), P (17.14 kg ha-1) and K (312.95 kg ha-1) were exhibited by the reduced tillage. The use of vermicompost resulted in the highest available soil N (185.93 kg ha-1) and K (316.68 kg ha-1), while the highest available soil P (18.22 kg ha-1) was observed with phospho-compost. The results revealed that conventional tillage combined with phospho-compost improves cotton yield and nutrient uptake, while reduced tillage along with the application of vermicompost and phospho-compost improves soil fertility. Therefore, combined use of tillage and organic inputs could be beneficial for enhancing soil properties and higher productivity of cotton in Vertisols as well as the whole of Maharashtra.

Biopriming using microbial consortia and biostimulants as a technique to increase seed quality of Solanum melongena L. by modifications in morphological and metabolic constituents

Brinjal (Solanum melongena L.) is a widely cultivated vegetable in tropical and subtropical regions. High-quality seeds are crucial for successful crop production, necessitating rapid and uniform field emergence. In the new wave of the Green Revolution, organic wastes were replaced by agrochemicals. This study was conducted from January to March 2024 to standardize biopriming techniques for brinjal using various organic inputs and microbial cultures to improve seed quality. Brinjal seeds cv. PLR 2 were treated with organic inputs (Panchagavya, Egg fermented extract, Fish fermented extract and effective microorganism solution) and liquid microbial cultures (Azospirillum and Pink Pigmented Facultative Methylotroph). The bioprimed seeds were assessed for their physiological attributes and anatomical and biochemical changes. Compared with the control, biopriming with 2% Fish fermented extract significantly improved the germination rate (19.4%), germination energy (40.9%), root length (44.4%), shoot length (24.4%) and seedling vigour index (68.1%). This increase was attributed to the nutritional and bioactive compounds in the fish by-products, which promoted root development and nutrient absorption. The biochemical parameters revealed increased ?-amylase activity, protein, and amino acid content in the bioprimed seeds. Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed beneficial root volatile compounds in the roots of treated seeds. An evaluation of the plant growth-promoting activities of the biopriming agents revealed the superiority of fish-fermented extract over other bioagents. Therefore, this method promotes sustainable agriculture and improved crop productivity, providing a scientific basis for biopriming as a viable alternative to conventional seed treatments.

Geochemical characteristics of crude oils and source rocks in the Malaysia-Thailand Joint Development Area (MTJDA), North Malay Basin

The Malaysia-Thailand Joint Development Area (MTJDA) that located in the North Malay Basin has been investigated in this study to resolve few issues concerning to petroleum potential and resources which has been abandon for decades. Despite Malay Basin having been proven to contain prolific oil and gas resources, the MTJDA which located in the Northern area however contains mainly gas with very minor oil. Thus, this study aimed to investigate the main factor that controls the hydrocarbon generation, type and distribution in this basin. The investigation involves biomarker characterization, thermal maturity assessment of source rock, crude oil and condensate, together with oil-oil and oil-source correlation that has never been established before. The geochemical data as indicated by bitumen extraction, GC-MS and Py-GC analyses on 40 cutting samples and 8 liquid samples (six oil samples and two condensate samples) revealed that the cutting samples were moderate in quality with variable richness based on TOC (total organic carbon) and a variable degree of maturity based on the biomarker proxy parameters of isoprenoid, hopanoid and steroid. The organic matter input for the source rock was derived from a mixed marine-terrestrial and terrestrial source and deposited in fluvial-deltaic/estuarine settings having oxic to sub-oxic depositional conditions. Based on biomarker fingerprints and proxy parameters, the oil and condensate samples were essentially of the same group, originating from a similar source rock, with some facies variation due to variations in organic matter input and degree of maturity. The results also indicated that the crude oil samples were originated from the coaly and carbonaceous shales of Group I, with mixed kerogen of type II/III that could produce gas with minor oil. There is also the possibility that these hydrocarbons were generated from a deeper interval of Group E (higher thermal maturity), deposited in a similar setting as Group I.

Flow-weighted sourcing of freshwater runoff from Pacific-draining continental and coastal basins in south-western Patagonia (41-56° S): characterizing regional inputs to Chilean fjords

Global estimates of the supply of dissolved and suspended materials to the ocean, in order to be relevant at either political or ecological scales, belie a finer-scale analysis necessary for understanding specific terrestrial-marine interactions. This is especially true for continental runoff to the marine critical zone of inland fjords and channels, where mechanisms, drivers, and predictions need to be elaborated in the context of changing land use and shifting climate forcing. In fjords in south-western Patagonia, runoff from small coastal and large continental basins (~310 x103 km2), sourced from a diverse geography and wide climatic gradient (<150 – 6,000+ mm/year), correspond with a very low density of hydrological and water quality observations. Based on the recently developed regional runoff model (FLOW), we estimated the coastal freshwater discharges and characterized flow-weighted sourcing (land use-cover type, climate, glaciers/geology, and soil province) for Pacific drainages from 41° to 56° south latitude. An estimated 692 km3/year (mean across 1979-2018), or 2% of worldwide total, is more than 85% of previous estimates for the much larger Pacific South American input. Based on limited water quality observations and inference from runoff sourcing, we predict general patterns of export for four groups of continental resources important for marine productivity, including: significant regional variation in flow seasonality, a N-S gradient in declining input of silicic acid and increased glacial input of sediment and iron, and potential shift in dissolved organic matter input sources from rainforest (potentially labile) to peatlands (refractory). Finally, we emphasize the temporal and spatial consequences of near-reference condition river runoff for marine ecosystem productivity and function in the Patagonian fjords, with specific recommendations for water quality standards and sustained monitoring for coupled river and marine ecosystems.

Effects of integrated fertilizer application on selected soil properties and yield attributes of common bean (Phaseolus vulgaris L.) on different soil types

In Ethiopia, common bean (Phaseolus vulgaris L.) productivity remains low because of low soil fertility. However, both plant production and soil fertility benefit from integrated application of fertilizers. Thus, this study investigates the effect of integrated application of inorganic, organic and biofertilizers on selected soil properties and yield components of common bean. A field experiment was conducted at three sites in southern Ethiopia, under two consecutive cropping season (2021 and 2022). The experiment was conducted using a randomized complete block design (RCBD) with three replications. The treatments included three levels of inorganic fertilizer (Triple Superphosphate, TSP), applied at 0, 42.5, and 85 kg TSP ha⁻1 for Kokate; 0, 29, and 58 kg TSP ha⁻1 for Hawassa; and 0, 35.5, and 71 kg TSP ha⁻1 for Alage, tailored to the specific conditions of each site. Additionally, the experiment incorporated three levels of organic inputs 0, 5 t biochar ha⁻1, and 5 t compost ha⁻1 as well as Rhizobium inoculation (HB-429) applied at 500 g ha⁻1. These treatments were designed to assess the combined effects of inorganic, organic and biofertilizers on soil health and crop performance. Results showed that the integrated application of inorganic, and organic fertilizers significantly (p ≤ 0.05) improved soil pH, soil organic carbon, and available P compared with the sole fertilizer application plots. Similarly, the integrated use of inorganic, organic and biofertilizers increased nodule numbers, seed weight, grain yield, and biomass yield. We also found that 23 and 24 % higher grain yield were achieved with integrated applications of TSP fertilizer with compost on Hawassa and Alage sites than sole inorganic fertilizer application. On the other hand, the integrated application of TSP fertilizer with biochar increased by 18 % grain yield on Kokate over the sole application of inorganic fertilizer. The highest economic benefit of 69,460 and 63,250 ETB was obtained from the integrated application of TSP fertilizer with compost at Hawassa and Alage sites, respectively. The highest economic benefit for the Kokate site was 53,583 ETB at TSP fertilizer with biochar application. Overall, the study confirms that site-specific integrated soil fertility management appears to be a prerequisite for sustainable and profitable common bean production over sole fertilizer application in southern Ethiopia.

Effect of organic inputs on the productivity of confectionery sesame (Sesamum indicum L.)

Organic farming is gaining momentum nowadays and the demand for organic food is increasing day by day. Field investigations were carried out during five consecutive summer seasons (2016, 2017, 2018, 2019, and 2020) at the Regional Research Station, Vridhachalam to optimize the organic inputs and to develop an organic production package for sesame. The field experiment comprised eight treatments with different organic inputs [farm yard manure (FYM), neem cake, biofertilizers, panchakavya] applied in different forms. The experiment was laid out in a randomized complete block design replicated thrice. The experimental results showed that the application of FYM @ 12.5 t/ha + seed treatment (Azospirillum + Phosphobacteria + PGPR each @ 600 g/ha of seed) + soil application of biofertilizer (Azospirillum + Phosphobacteria + PGPR each @ 2 kg/ha of seed) and foliar application of 3% panchagavya at 35 and 45 DAS recorded a higher seed yield (783 kg/ha).

Differences in soil biological activity and soil organic matter status only in the topsoil of Ferralsols under five land uses (Allada, Benin)

Land use change on the Ferralsols of the Allada Plateau in southern Benin has led to a slight decline in soil organic carbon (SOC) stocks over the last two decades. However, as in many African landscapes, detailed characterisation and quantified data on the SOC stocks and soil biological activity under major land uses are still poorly understood. The aim of this study was to characterise the biological activity and organic matter status of Ferralsols (0–30 cm) under the five major land uses on the Allada Plateau, i.e., forests, tree plantations, young and adult palm groves, and croplands (pineapple, maize). Soil biological activity was assessed using the standardised litter decomposition method (Tea bag index) and soil respiration (during a 28-day soil incubation). Soil organic matter status was characterised by quantifying SOC pools: soil microbial biomass carbon (MB-C), potassium permanganate oxidisable carbon (POX-C), and SOC associated to soil particle-size fractions (e.g. particulate organic matter, POM, and SOC associated to the clay soil fraction). The results indicated that SOC pools and biological activity were lower in tree plantations than in forests. The standardised litter decomposition was also slower in tree plantations than in forest. In croplands and palm groves, SOC pools and soil microbial biomass and respiration were lower than in forests and tree plantations. This high level of biological activity in forests, and at a lesser level in tree plantations, was effective in accumulating carbon in C pools associated to the clay fraction. Agricultural land uses, such as croplands and palm groves decreased all the soil C pools even those associated to the clay fraction, except for POX-C. However, these land-use effects on SOC pools decreased strongly with depth. At 10–30 cm, the differences in SOC pools or soil respiration between the five land uses were no more noticeable. Our results indicated that the amount of organic inputs was an essential factor to sustain high soil biological activity and SOC stabilisation in the clay size fraction, but only in the topsoil. Maintaining forests in the landscape is a priority in order to preserve SOC stocks and soil biological activity, which neither monospecific tree plantations nor cultivation can do at the same level.

INFLUENCE OF MINERAL NUTRITION ON THE SOIL HEALTH AND PRODUCTIVITY OF COCONUT PALMS (Cocos nucifera L.) IN TROPICAL LAND USE SYSTEMS

Perennial plantation crops, such as coconut trees require the systematic addition of nutrients for sustained growth and productivity. This study aimed to understand plant and soil nutrient dynamics, root health and soil biological properties upon addition of specific nutrients in tropical land use systems. Field experiments in randomised block design were conducted in Agro-Ecological Unit-3 (AEU-3) and Agro-Ecological Unit-9 (AEU-9) from 2014 to 2020. Treatments were T1 (site-specific nutrient management practices (SSNM), T2 (SSNM without sodium chloride); T3 (SSNM without gypsum); T4 (SSNM along with the 50 g microbial formulation Kera Probio); T5 (Farming practice without any amendments or nutrients). Root health parameters, cumulative nut yield and nutrient dynamics in soil and leaf samples were estimated at the beginning and the end of the study. Systematic provision of all the essential nutrients resulted in significant increase content of N (1.39%), P (0.164%), K (1.71%), Ca (0.406%) and Mg (0.175%) in index leaves of coconut trees in sandy soils. Foliar nutrient levels of coconut trees grown in laterite soils were 1.21% N, 0.142% P, 1.27% K, 0.504% Ca and 0.146% Mg. In AEU-3, treatment that received all amendments and nutrients showed highest organic carbon content at the three depths as 6.79 g kg-1soil, 5.39 g kg-1 soil and 3.82 g kg-1, soil, respectively. In AEU-3, 61% increase in yield was observed, while in AEU-9,40% increase was recorded. Application of gypsum resulted in downward displacement of K and Mg indicating that gypsum is required for the amelioration of sub soil acidity in sandy soils. However, the displacement effect was less pronounced in laterite soils and beneficial effect of gypsum was evident with the enhancement of exchangeable Ca. Hence sandy soils require application of inputs as per T3 (T1 without gypsum), with external organic inputs and palm residues whereas in laterite soils application of treatments as per T1 is required with in situ palm residue recycling. Key words: coconut, leaf nutrients, sandy soil, laterite soil, root health, dehydrogenase.

The Early Cretaceous Sembar Formation, Southern Indus Basin, Pakistan: Biomarkers and Trace Element Distributions to Investigate the Sedimentary Palaeoenvironment and Organic Matter Input.

The Early Cretaceous clay-rich facies of the Sembar Formation represent the most significantly occurring organic-rich sediments in the Southern Indus Basin of Pakistan. In this study, detailed geochemical research of total organic carbon, biomarker, mineralogy and trace elemental compositions, together with kerogen microscopic analysis, were carried out and used to understand the organic matter input and the dispositional environmental setting of the organic-rich Sembar shale. The Sembar shales have high organic matter, as indicated by the total organic carbon (TOC) content of up to 2.31 wt %. These shales contain a high abundance of liptinites (i.e., alginite and bituminite), with significant reactive vitrinite maceral, reflecting a mixed-organic matter with a high contribution of marine-derived input. The biomarker distributions evidence the finding of mainly marine organic matter. The biomarker characteristics such as Pr/Ph, Pr/n-C17, Ph/n-C18, and tricyclic terpane ratios together with C27-C29 regular sterane distributions show that the source of organic matter was primarily marine-derived from mainly phytoplankton algae, along with amounts of land plant input, and accumulated under a low oxygenated environment. The Sembar shale facies are characterized by high Mo trace element content and high V/Ni and Mo/TOC ratios, suggesting anoxic and nonsulfidic environmental conditions during time deposition. The geochemical proxies such as the Sr/Ba ratio and gammacerane/C30 hopane (G/C30) index suggest that the Sembar shale facies were deposited in a relatively low moderate stratified water column. The higher gallium (Ga) than rubidium (Rb), with high Ga/Rb ratios, indicates a high abundance of the kaolinite mineral, thereby deducing the subaerial weathering during the warm and humid climatic conditions. In this case, these warm and humid climatic conditions cause an influx of masses of nutrients, which could be attributed to increasing marine primary bioproductivity. These large masses of nutrients into the photic zone are also attributed to the presence of the upwelling system during the deposition time. Therefore, such conditions of bioproductivity and preservation of organic matter (OM) resulted in the accumulation of organic carbon in the shale facies of the Early Cretaceous Sembar Formation.