Replicate Plots Research Articles

Fire and ant interactions mediated by honeydew and extrafloral nectar in an australian tropical savanna

Fire is a major disturbance affecting ecosystems globally, but its impact on mutualisms has received minimal attention. Here, we use a long-term field experiment to investigate the impact of different fire regimes on globally important ant–honeydew and ant–extrafloral nectar (EFN) mutualistic interactions in an Australian tropical savanna. These interactions provide ants with a key energy source, while their plant and hemipteran hosts receive protection services. We examined ant interactions on species of Eucalyptus (lacking EFNs) and Acacia (with EFNs) in three replicate plots each of burning every 2 and 3 years early in the dry season, burning late in the dry season every 2 years, and unburnt for > 25 years. The proportions of plants with ant–honeydew interactions in Acacia (44.6%) and Eucalyptus (36.3%) were double those of Acacia plants with ant–EFN interactions (18.9%). The most common ants, representing 85% of all interactions, were behaviourally dominant species of Oecophylla, Iridomyrmex and Papyrius. Fire promoted the incidence of ant interactions, especially those involving EFNs on Acacia, which occurred on only 3% of plants in unburnt plots compared with 24% in frequently burnt plots. Fire also promoted the relative incidence of behaviourally dominant ants, which are considered the highest quality mutualists. Contrary to expectations, frequent fire did not result in a switching of behaviourally dominant ant partners from forest-adapted Oecophylla to arid-adapted Iridomyrmex. Our findings that frequent fire increases ant interactions mediated by honeydew and extrafloral nectar, and promotes the quality of ant mutualists, have important implications for protective services provided by ants in highly fire-prone ecosystems.

After the Megafires: Effects of Fire Severity on Reptile Species Richness and Occupancy in South-Eastern Australia

The Australian megafires of 2019–2020 were considered catastrophic for flora and fauna, yet little is known about their impacts on reptiles. We investigated the impacts of the 2019–2020 megafires on reptiles in Morton National Park, New South Wales, in eastern Australia. To understand how fire severity affects reptile species richness and occupancy, we surveyed 28 replicate plots across unburnt areas and areas affected by high and low fire severity. We estimated reptile species richness and occupancy by performing systematic searches for reptiles during five sampling occasions in 2023, three years after the megafires. We measured vegetation structure and quantified the thermal environment in shelter sites used by reptiles. Vegetation structure varied significantly between burn severity groups. High-severity plots had the least canopy cover and the thinnest leaf litter depth but had a taller understorey with more stems. The thermal quality within reptile retreat sites did not differ between fire severity classes. Despite strong differences in post-fire vegetation structure, there was no evidence that fire severity affected reptile species richness or occupancy of the delicate skink, Lampropholis delicata. These results highlight the complexity of reptile responses to fires and contribute to increasing our understanding of the impacts of megafires on reptile communities.

Differential Responses of Soil Nitrogen Forms to Climate Warming in Castanopsis hystrix and Quercus aliena Forests of China

Climate warming impacts soil nitrogen cycling in forest ecosystems, thus influencing their productivity, but this has not yet been sufficiently studied. Experiments commenced in January 2012 in a subtropical Castanopsis hystrix Hook. f. and Thomson ex A. DC. plantation and in May 2011 in a temperate Quercus aliena Blume forest, China. Four treatments were established comprising trenching, artificial warming (up to 2 °C), artificial warming + trenching, and untreated control plots. The plots were 2 × 3 m in size. In 2021 and 2022, soil nitrogen mineralization, soil nutrient availability, fine root biomass and microbial biomass were measured at 0–20 cm soil depth in 6 replicate plots per treatment. Warming significantly increased soil temperature in both forests. In the C. hystrix plantation, warming significantly increased available phosphorus (AP) and fine root biomass (FRB), but it did not affect soil microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP) and their ratios. Warming depressed the net mineralization rate (NMR) and net ammonification rate (NAR) of the C. hystrix plantation, probably because the competition for nitrogen uptake by fine roots and microorganisms increased, thus decreasing substrates for nitrogen mineralization and ammonification processes. Trenching and warming + trenching increased the net nitrification rate (NNR), which might be related to decreased NH4+-N absorption of trees in the trenched plots and the increased microbial activity involved in soil nitrification. In the Q. aliena forest, warming significantly increased NH4+-N, MBC/MBN, Root C/N, Root N/P, and decreased pH, MBN, MBN/MBP and Root P; and there was no effect of trenching. Notably, the NAR, NNR and NMR were largely unaffected by long-term warming. We attributed this to the negative effect of increasing NH4+-N and decreasing MBN/MBP offsetting the positive effect of soil warming. This study highlights the vulnerability of subtropical forest stands to long-term warming due to decreased soil N mineralization and increased NO3−-N leaching. In contrast, the soil N cycle in the temperate forest was more resilient to a decade of continuous warming.

Effect of Manure Dosage on the Growth and Yield of Bambara Beans through a Multilocation Test

The purpose of this study is to determine the suitability and productivity level of Bambara beans in the Special Region of Yogyakarta, especially to determine and examine the effect of the use of organic fertilizer from livestock manure on the growth and yield of Bambara beans. The implementation of the study involved a multi-location test of Bambara bean cultivation in three subdistricts, namely Tempel, Sedayu, and Cangkringan. In these three areas, manure was applied with 3 dose variations, namely 10 tons/Ha, 20 tons/ha and 30 tons/ha. The study was arranged in a Completely Randomized Design (CRD) where each treatment was carried out with 3 replication plots. The test results showed that the dose of manure was not significantly different from the production of Bambara beans. Therefore, a dose of manure of 10 tons/ha can be recommended to achieve higher economic benefits in Bambara bean cultivation. In addition, based on the evaluation of the growth phase and plant yield, the location of Bambara bean planting in Tempel gave higher yields compared to Sedayu and Cangkringan. Bambara bean cultivation in Tempel can produce 686.45 g/plot. Keywords: Bambara beans, Growth, Multilocation test, Organic fertilizer, Yield.

Simulated fire injury: effects of trunk girdling and partial defoliation on reproductive development of apple trees (Malus domestica)

Fire damage can significantly impact fruit productivity in orchards. However, the effects of nonlethal fire injuries on the reproductive development of apple trees remain poorly understood. To investigate these effects, we implemented three treatments: trunk girdling to simulate fire injury to xylem, defoliation of a third of the canopy (simulated crown fire injury), and a combined treatment (simulated surface fire injury), alongside a control. The experiment was conducted during the 2021–22 growing season using a randomised block design with four biological replicate plots. Girdling was less effective than crown and surface fire treatments in influencing fruit composition during the current growing season, and flowering and fruiting in the following season. The crown and surface fire treatments induced localised detrimental effects on fruit sugar and titratable acidity while stimulating peel blush. Additionally, these treatments led to reduced starch reserves by harvest, which likely disrupted subsequent flowering and crop load near the previously defoliated sections of the canopy. When surface fires damage leaves near the base of the canopy in addition to the trunk, fruit production in the lower part of the canopy is more likely to be compromised in the following season. Crown fires, which cause leaf loss near the apex of the canopy, appear to be particularly detrimental to tree productivity, as the top defoliation treatment impaired carbohydrate reserves in shoot terminals and roots. In conclusion, fire-induced loss of leaf area during fruit growth alters fruit composition in the current growing season and may lead to lower yields in the subsequent season.

Improvement of soil health and leaf nutrient status in strawberry (Fragaria × ananassa) using bioorganic formulations

In strawberry cultivation, a variety of factors influence production and fruit quality. Yield is the most crucial component in fruit production. Chemical fertilizers are typically used to boost yields, however because of their high production costs, negative effects on the environment and human health, organic fertilizers or natural amendments are being utilized instead of chemical fertilizers. The primary goals of substituting chemical fertilizers with bioorganic formulations made from natural sources for fruit production are to lower costs of production and maintain fruit production sustainability. Therefore, to study the impact of these bioorganic formulations the current investigations were conducted in open field conditions under sub humid mid hills conditions of Himachal Pradesh with 12 treatment combinations and three replicate plots. The tested plants were given various combinations of bioorganic formulations [Jeevamrit (JE) and Ghanjeevamrit (GHA)] as a source of nutrients. When compared to conventional practices, statistically significant improvements were discovered in the parameters of yield and nutrient content in the soil and plant. Significant higher yield (21.13 tonnes/ha), soil nutrients and total microbial content was recorded in T4. The results of this study provide support to the recommendation that bioorganic formulations, such as the tested ones, be used on their own or in combination as a substitute for chemical fertilizers in plant nutrition for the production of strawberries.

Unconventional Strategies for Aphid Management in Sorghum.

Since the invasion of the sorghum aphid Melanaphis sorghi (Theobald), farmers in the sorghum (Sorghum bicolor L. Moench) production region in the Great Plains of the U.S. have faced significant crop damage and reduced yields. One widely used practice to aid in managing sorghum aphids is pest monitoring, which often results in field-level insecticide applications when an economic threshold is reached. However, relying on this traditional management practice includes the application of insecticides to non-infested plants. To reduce insecticide usage in sorghum, we proposed spraying individual plants when aphids are present or absent compared to traditional spraying based on a standard economic threshold using field replicate plots over two summer seasons. The experimental results of this study indicated fewer aphids in plots managed with an economic threshold, followed by randomly sprayed and plant-specific treatments compared with the untreated control treatment. Therefore, compared with traditional management, those treatments can be alternative strategies for managing aphids on sorghum within our field plot study.

Influence of maize genotypes and harvest stages on in-silo fermentation quality and nutritional value of corn silage during hot summer condition of the tropics

The aim of the experiment was to evaluate the potential of promising summer maize genotypes and optimal stage of harvesting these genotypes for ensiling in terms of dry matter (DM), starch, and crude protein (CP) yields, silage fermentation quality, nutrients profile, total digestible nutrients, metabolizable energy (ME) content, Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate (CHO) subfractions composition, in vitro DM digestibility (DMD) and in situ starch degradation characteristics. Six maize genotypes were chosen for the study: DK9108 from Monsanto, P30Y87, P3939 from Pioneer, QPM-300 (quality protein maize) and W94 from the International Maize and Wheat Improvement Center (CIMMYT), and a local cultivar, Afgoii, from the Cereal Research Institute (Persabaq, KP). A total of 72 plots (8 m × 10 m) were blocked in three replicate fields, and within each field, each genotype was sown in four replicate plots according to a randomized complete block design. For the data analysis, the Proc-Mixed procedure of Statistical Analysis System with repeated measure analysis of variance was used. The DM yield was strongly influenced (P < 0.001) by maize genotypes, varying from 12.6 to 17.0 tons/ha. Except for total CHO and ammonia nitrogen (NH3-N), the contents of all measured chemical components varied (P < 0.001) among the genotypes. Further comparison revealed that, genotype P3939 had a higher (P < 0.05) content of CP (7.27 vs. 6.92%), starch (36.7 vs. 27.9%), DMD (65.4 vs. 60.0%), ME (2.51 vs. 2.30 Mcal/kg) and lactic acid (5.32 vs. 4.83%) and lowest content of NDF (37.3 vs. 43.1%), pH (3.7 vs. 4.10) compared to the local cultivar (Afgoii). Advancement of post-flowering maturity from 25 to 35% DM (23 to 41 days after flowering (DAF)) increased (P < 0.05) the DM yield (10.4 to 17.8 tons/ha), starch content (29.1 to 35.0%), DMD (65.3 to 67.3%) and ME (2.34 to 2.47 Mcal/kg), and decreased (P < 0.001) the contents of CP (7.42–6.73%), NDF (48.8–38.5%), pH (4.10 to 3.60), NH3-N (8.93–7.80%N) and effective degradability of starch (95.4 to 89.4). Results showed that for higher yields and silage nutritional and fermentation quality, maize crops should be harvested at whole crop DM content of 30–35% (34 to 41 DAF). It was further concluded that genotype P3939 is the most suitable summer maize genotype for silage production in terms of yields and silage nutritional and fermentation quality under the hot environmental conditions of the tropics.

Land-use intensification exerts a greater influence on soil microbial communities than seasonal variations in the Taihu Lake region, China

The Taihu Lake region has undergone intensive land-use conversions from natural wetlands (NW) to conventional rice-wheat rotation fields (RW) and further to greenhouse vegetable fields (GH). Nevertheless, the effects of these conversions on soil microbes, particularly in wetland ecosystem, are not well explicit. To explore the impact of land-use intensification on soil microbial communities, monthly soil samples were obtained from replicate plots representing three land-use types (NW, RW, and GH) in subtropical wetlands and then subjected to amplicon sequencing. Land-use intensification had direct effects on bacterial and fungal community composition, with a more pronounced impact on bacteria than on fungi. These changes in bacterial communities were closely correlated with variations in soil environmental variables, such as NO3−-N, pH, and electrical conductivity. Land-use intensification led to a decrease in bacterial deterministic processes, with an opposing trend observed in the fungal community. In addition, arable lands (RW and GH), which are affected by anthropogenic activities, exhibited more complex networks. Potential metabolic functional groups in GH had higher absolute abundance. Seasonal variations significantly influenced microbial diversity, composition, and potential metabolic functional groups within each land-use type, particularly in summer, although the magnitude of this impact was much smaller than the impact of land-use intensification. Our findings emphasize the importance of comprehending the ecological consequences of land-use intensification in wetlands for sustainable resource management and biodiversity conservation.

Anaerobic Soil Disinfestation and Vermicompost to Manage Bottom Rot in Organic Lettuce.

Rhizoctonia solani Kühn (teleomorph: Thanatephorus cucumeris [Frank] Donk) is an aggressive soilborne pathogen with a wide host range that survives saprophytically between crops, presenting a challenge for organic vegetable farmers who lack effective management tools. A 2-year field experiment was conducted at two organic farms to compare anaerobic soil disinfestation (ASD) and worm-cured compost (vermicompost) to manage bottom rot caused by R. solani subspecies AG1-IB in field-grown organic lettuce (Lactuca sativa). At each farm, four replicate plots of seven treatments were arranged in a randomized complete block design. Randomization was restricted by grouping treatments to evaluate ASD, and treatments to evaluate vermicompost in starter plugs. ASD experiment treatments were three different ASD carbon sources that are commonly used and widely available to local farmers in Vermont: compost, cover crop residues, and poultry manure fertilizer, as well as a tarped control. Vermicompost experimental treatments were vermicompost compared with two types of controls: a commercial biocontrol product (RootShield PLUS + G), and unamended (untarped control). This study demonstrated that the ASD method is achievable in a field setting on Vermont farms. However, neither ASD nor vermicompost produced significant disease suppression or resulted in higher marketable yields than standard growing practices. Given the laborious nature of ASD, it is likely more appropriate in a greenhouse setting with high-value crops that could especially benefit from being grown in plastic tarped beds (e.g., tomatoes and strawberries). This study is the first known attempt of field-implemented ASD for soil pathogen control in the northeastern United States.

Prolonged soybean absence in the field selects for rhizobia that accumulate more polyhydroxybutyrate during symbiosis

AbstractDuring symbiosis, C that rhizobia respire to power N fixation can be stored as polyhydroxybutyrate (PHB), shown to support rhizobia survival under laboratory starvation. We collected soil in 2015 from four replicate plots per treatment in two long‐term experiments at Waseca, MN. Treatments differed in the intervals between soybean [Glycine max (L.) Merr.] hosts. We measured PHB accumulation in eight nodules per plant from four soybean (cv. MN0095) trap plants per soil sample. Trap plants were arranged in a greenhouse, common‐garden experiment, and PHB accumulation was measured using flow cytometry. Treatments sampled after long intervals without soybean (greater than 2 years) showed a greater relative abundance of high‐PHB strains. Treatments sampled after the first year of soybean following 5 years of a non‐host crop showed a decreased relative abundance of high‐PHB strains, compared to treatments sampled after long intervals without soybean. The latter result is consistent with the hypothesis (not tested directly here) that some high‐PHB strains were “sanctioned” by plants as less beneficial. Our results suggest that rhizobia strains with the tendency to allocate more C to N fixation at the expense of PHB accumulation may be less likely to persist where soybean is grown infrequently or where soil conditions make PHB particularly valuable. However, with typical 2‐year rotations in Minnesota, differences in PHB storage are unlikely to have a major effect on the relative survival of strains.

Analysis of Genetic Diversity in Greengram (Vigna radiata L. Wilczek)

The current study titled “Analysis of genetic diversity in green gram [Vigna radiata (L.) Wilczek]” was carried out at Center for Crop Research (C.R.C.), Sardar Vallabhbhai Patel University of Agriculture &amp; Technology, Meerut. A set of twenty five mungbean genotypes were examined to investigate the essence and extend of divergence of genes using Mahalanobis’s D2 Statistics on twelve critical quantitative attributes. The study material was assessed using Randomized Block Design (RBD) with three replication plots of two rows of 4 meter length. Out of every replication, five plants were selected at random, marked, and observations were recorded for twelve quantitative attributes. Analysis of variance showed that there was significant variation among all characters examined. The twenty-five genotypes of mungbean have been split into seven distinct clusters. With seven genotypes apiece, Cluster I and Cluster IV were determined to be the largest. The intra cluster distance was maximum for Cluster IV. The maximum inter cluster distance between cluster V and cluster II suggests that the genotypes in these clusters doesn't correlate with one another and the minimal inter-cluster distance between cluster V and cluster IV demonstrates a high degree of connection between the genotypes in these clusters. Based on high inter cluster distances, hybridization programme could be taken up between the varieties of cluster II (Pusa Vaishali, IPM-02-19, IPM 02-19, OMG-1045, VBG-04-008) and cluster V (Pusa-0871, Pusa-0891, SMM-15-72, PDM-262).Hence, these nine genotypes are recognized as promising progenitors and can be employed in further breeding programme. Plant height, number of branches/plants, number of pods/plant, number of pods/clusters, pod length, biological yield, harvest index and seed yield per plant are vital for genetic diversity and were recognized as significant contributors to genetic divergence.

Large contribution of soil N2O emission to the global warming potential of a large-scale oil palm plantation despite changing from conventional to reduced management practices

Abstract. Conventional management of oil palm plantations, involving high fertilization rate and herbicide application, results in high yield but with large soil greenhouse gas (GHG) emissions. This study aimed to assess a practical alternative to conventional management, namely reduced fertilization with mechanical weeding, to decrease soil GHG emissions without sacrificing production. We established a full factorial experiment with two fertilization rates (conventional and reduced fertilization, equal to nutrients exported via fruit harvest) and two weeding methods (herbicide and mechanical), each with four replicate plots, since 2016 in a ≥ 15-year-old, large-scale oil palm plantation in Indonesia. Soil CO2, N2O, and CH4 fluxes were measured during 2019–2020, and yield was measured during 2017–2020. Fresh fruit yield (30 ± 1 Mgha-1yr-1) and soil GHG fluxes did not differ among treatments (P≥ 0.11), implying legacy effects of over a decade of conventional management prior to the start of the experiment. Annual soil GHG fluxes were 5.5 ± 0.2 Mg CO2-C ha−1 yr−1, 3.6 ± 0.7 kg N2O-N ha−1 yr−1, and −1.5 ± 0.1 kg CH4-C ha−1 yr−1 across treatments. The palm circle, where fertilizers are commonly applied, covered 18 % of the plantation area but accounted for 79 % of soil N2O emission. The net primary production of this oil palm plantation was 17 150 ± 260 kgCha-1yr-1, but 62 % of this was removed by fruit harvest. The global warming potential of this planation was 3010 ± 750 kgCO2eqha-1yr-1, of which 55 % was contributed by soil N2O emission and only &lt; 2 % offset by the soil CH4 sink.

GENETIC EVALUATION FOR SEED YIELD AND ITS COMPONENT TRAITS IN SUNFLOWER (HELIANTHUS ANNUUS L.) USING LINE × TESTER APPROACH

Sunflower is a vital oilseed crop, but yield improvement remains a major objective. Exploring germplasm and exploiting non-additive gene action can help overcome yield limitations and identify superior parental lines and crosses for hybrid development through GCA and SCA. Four parental lines (A-1, A-2, A-3, and A-4) were crossed with three testers (B-1, B-2, B-3) in a line × tester fashion to generate F0 seeds. These seeds were planted using a randomized complete block design (RCBD) with three replicate plots in the field to ensure unbiased results. Data on various growth and yield parameters is collected and analyzed using Analysis of variance and combining ability analysis. Lines A-3 and A-4 and tester B-3 demonstrated consistently positive GCA effects for several traits, signifying their broad genetic value for hybrid development. The hybrid A-4 × B-1 emerged as the top performer, exhibiting exceptional SCA effects in days to flowering, seed yield per head and height of the plant, indicating exceptional compatibility between these parental lines. Lines A-3 and A-4 displayed significant positive GCA effects for key parameters like head diameter and seed yield. Tester B-3 also contributed to enhanced yield traits in hybrid combinations. Lines A-3 and A-4, tester B-3, and hybrid A-4 × B-1 emerged as promising parents for sunflower hybrid development due to their superior GCA and SCA effects. These findings offer valuable resources for future breeding programs that enhance sunflower yield and productivity.

Integrating pastured meat chickens into organic vegetable production increased nitrogen and microbial biomass with variability in presence of E. coli and Salmonella spp

Abstract Integrating animals into a farm supports a closed or semi-closed production system where nutrients are recycled and off-farm inputs are reduced. In comparison to other livestock, chickens can be a low-investment option for animal-crop integration of small-scale, diversified, vegetable farms. Although crop-animal integration poses many potential benefits to farms, soils, and the environment, there are significant food safety risks when considering the production of vegetables in close proximity to raw manure. The objectives of this study were to examine the effects of poultry integration with meat chickens (broilers) in two different seasons on soil health, food safety, vegetable yield, and poultry feed efficiency in organic vegetable cropping systems. We explored these effects in an open field study with three rotation treatments (two that integrated chickens and a no-chicken control): vegetables-cover crop (V-CC; control treatment), vegetables-cover crop-poultry (V-CC-P), and vegetables-poultry-cover crop (V-P-CC). In response to crop rotation, over three years, we monitored soil nutrient status, soil microbial biomass carbon (MBC), permanganate oxidizable carbon (POXC), and microbial catabolic potential and diversity using Biolog® microplates. The presence or absence of foodborne pathogens in soil and vegetables was also measured. Nitrate–nitrogen (NO3–N) was higher in V-P-CC in year 2 as compared to both V-CC and V-CC-P (P = 0.001 and &lt;0.001, respectively). After poultry removal in the summer of year 2 and year 3 V-P-CC was on average two times higher in NO3–N as compared to V-CC and V-CC-P, respectively. After chicken removal in the autumn of year 3 V-CC-P was 2.1 and 1.8 times higher in NO3–N as compared to V-CC and V-P-CC, respectively. On average phosphorus (P) increased by 45% in year 2 and by 13.2% in year 3. Microbial biomass carbon (MBC) increased from after harvest (summer) in year 1 to the end of the season (autumn) of year 2 from 219.75 to 303.23 mg carbon (C) kg−1. Integrating poultry increased MBC by 25%, on average between both treatments across all sampling dates, compared to the V-CC (P = 0.042). The vegetable-cover crop control (V-CC) preferentially used carbohydrates, compared to V-P-CC which corresponded to greater amino acid usage. Escherichia coli O157:H7 was detected in all plots in the spring of year 3 and select replications of plots in the autumn of year 3. Salmonella spp. was found in one plot in year 2. No pathogens were detected on the spinach crop when leaf surfaces were tested. Integrating chickens into organic vegetable crop rotations increases NO3–N and has the potential for off-farm fertilizer reductions if time and stocking density are further examined. However, poultry feed is often an off-farm input and should be considered when determining the true N input of this system. Soil health may be improved, but MBC and other soil health indicators should be monitored with longer-term rotations. There are food safety risks that come with the integration of chickens into vegetable production and fields should be treated as if raw manure has been applied. Despite the potential benefits of integrating poultry into vegetable crop rotations, more research on these systems is required to determine optimum integration strategies that provide maximum benefit to the producer, the animals, and the environment.

Soil Quality Indicators under Different Smallholder Managed Cropping and Landuse Practices in Abuja, Nigeria

There are limited reports about the impacts of smallholder-managed cropping and land-use practices (CLUPs) on soil quality, especially in developing countries. This study investigates the impact of six different Cropping Land Use Practices (CLUPs) on soil quality parameters in Abuja, Nigeria, focusing on sesame mono-cropping (SM), guinea corn mono-cropping (GCM), yam mono-cropping (YM), maize + yam mixed cropping (MYM), maize mono-cropping (MM), and natural forest (NF). The objectives are to determine Soil Organic Carbon (SOC), Total Nitrogen (TN), and pH values in the six CLUPs and assess differences under various CLUPs and soil depths. The study conducted in the University of Abuja Permanent Site, covers 11,000 hectares and analyzes soil samples from three replicate plots per CLUP, considering topsoil (0-15cm) and subsoil (20-30cm). The results indicate slightly acidic soils with low SOC and TN contents. Significant differences in SOC, TN, and C/N ratio are observed among cropping systems, with mixed cropping (MYM) promoting higher SOC. The C/N ratio is consistently low across CLUPs, indicating accelerated decomposition. While intra-plot soil heterogeneity is low, significant declines in soil quality indicators are noted under cropping systems compared to the natural forest. The study recommends site-specific, sustainable land management practices tailored to each cropping system. Encouraging organic matter additions, such as using animal and farmyard manure, is proposed to enhance soil fertility and reverse degradation trends. The findings contribute to understanding how diverse cropping practices impact soil quality, providing valuable insights for sustainable land management in the Abuja region.

Comparing the yield of maize (Zea mays L.) hybrids in organic and conventional agriculture

The European Green Deal was published by the European Commission in 2019. The main aim of the program is to reach net zero greenhouse gas emissions by 2050, making Europe the first climate-neutral continent in the world. To achieve this, criteria are also set for agriculture: increasing the share of land under organic farming to 25%, reducing the use of fertilisers and pesticides. However, the benefits of organic farming are widely debated. The aim of our study was to compare the yield of maize (Zea mays L.) hybrids bred in Martonvasar in two different cropping environments. The silage yields of 20 different maize hybrids were evaluated in a three replicate small plot experiment in an organic field and an adjacent conventional field. The average green mass yield of the hybrids was 36,58 t ha-1 in the organic field and 43,03 t ha-1 in the conventional. The green mass yield in the organic area was 20% lower than in the conventional area, and the dry matter yield and digestible dry matter yield were about 18% lower. Hybrids of different maturity groups responded differently to organic cultivation. The yields of early hybrids decreased more and late hybrids less in the organic farming compared to the conventional production.

Fire regime shapes butterfly communities through changes in nectar resources in an Australian tropical savanna

AbstractFire‐dependent savanna provides key habitat for butterflies globally, but we know little about how fire regimes, including fire frequency and season, affect them. These impacts are likely to be primarily indirect, through changes in overall habitat structure, the abundance of larval host plants, and/or the provision of nectar resources for adults. We examined the relationships among fire regime, butterfly abundance and diversity, and vegetation structure and floral resources within a long‐term fire experiment near Darwin in the Australian monsoon tropics. We surveyed butterflies and floral resources throughout the 2019–2020 wet season in three replicate plots of each of six experimental treatments that had been operating for 15 years. All plots subject to fire had been burned in the previous dry season. We observed 24 butterfly species and 280 individuals representing all five butterfly families found in Northern Australia. Butterfly abundance was highest under early dry‐season (June) fire regimes (mean = 11.9 individuals per plot survey) compared with a late dry‐season (October) regime (mean = 6.7) and in the long‐term absence of fire (mean = 5.3), and this was correlated with the abundance of floral resources. The distribution of butterflies was also highly associated with floral resources within plots regardless of fire treatment. Butterfly species richness was significantly higher in early dry‐season (mean = 6.8) compared with unburned (mean = 3.3) plots but did not differ between early and late dry‐season (mean = 4.7) plots. Butterfly and floral diversity were similar across all early dry‐season fire treatments regardless of whether they had been burned every 1, 2, 3, or 5 years. Our finding that early dry‐season burning promotes butterfly diversity and abundance by increasing the supply of nectar resources has important implications for biodiversity management more broadly, given that nectar is a critical resource for many animal taxa.

The Effect of Giving Liquid Organic Fertilizer Made from Cow Urine Enriched by Agricultural Symbiotic Microbes on the Production of Taiwan Grass (Pennisetum purpureum Cv. Mott)

This research aims to determine the effect of adding liquid organic fertilizer (POC) made from cow urine and agricultural symbiotic microbes on the growth and production of Taiwan grass (Pennisetum purpureum Cv. Mott). The research location is Natai Raya Village, Kumai District, West Kotawaringin Regency. The research method used a unidirectional Randomized Block Design (RAK) with 3 fertilizer treatments applied to Taiwanese grass with 6 replication plots. Treatment consists of: P1 using chemical fertilizer (PK) 100% NPK 200 kg/ha (40 g/plant) or P2 using PK 100%+25% POC (100 ml/plant), and P3 using PK 100%+50 % POC (200 ml/plant). The parameters observed were: plant height, stem diameter, number of tillers, leaf length, fresh weight production (BS), dry matter production (DW) and organic matter production (BO). The results of the study showed that there was a significant increase (P&lt;0.05) with the addition of POC on the growth and production of Taiwan grass. Plant height increased significantly, the highest at P3 was 91.6 cm, an increase of 32.2% compared to P1 of 69.3 cm, at P2 it increased by 16.1%. The largest stem diameter in P3 was 2.18 cm, an increase of 29.9% compared to P1 of 1.68 cm, P2 increased 13.7%. The highest number of offspring at P3 18.56 increased 45.5% compared to P1 12.75, P2 increased 24.9%. The length of the longest leaf on P3 was 77.46 cm, an increase of 40.5% compared to P1 of 55.13 cm, P2 increased 34.55%. The highest BS production was at P3 28,550 tons/ha, an increase of 22.37% compared to P1 23.33 tons/ha, P2 increased 9.74%. BK production was highest at P3 13.38 tonnes/ha, an increase of 25.6% compared to P1 10.62 tonnes/ha, P2 increased 12.5%. The highest BO production was at P3 7,208 tonnes/ha, an increase of 30.62% compared to P1 5.51 tonnes/ha, P2 increased 15.92%. The conclusion of this research is that the higher the dose of liquid organic fertilizer made from cow urine, the higher the growth and production of Taiwanese grass. The optimal fertilizer dose is 100% chemical fertilizer treatment with added liquid organic fertilizer made from 50% cow urine. Keywords : Chemical fertilizer; liquid organic fertilizer; cow urine; agricultural symbiotic microbes; growth and production; Taiwan grass

Selüloz ve PLA Biyopolimer Nonwoven Malçların Toprak Sağlığına Etkisi

The nonwoven mulches produced from regenerated viscose and PLA fibres as well as conventional agro foil were placed on the soil by randomly arranged blocks of four replication plots. After 50 days, the soil samples beneath each mulch and on the control field were collected, where the bacteria and fungi population as well as the physio-chemical properties of the soil were measured. The severe reduction in bacterial population in soil under the agro foil and mulches made of PLA fibres occurs due to the prevalence of high soil temperature. The bacterial population of soil beneath the mulches made of viscose fibre significantly increased due to favourable anaerobic conditions, respectively soil temperature and moisture. Under all mulches, compared to the control field, a higher fungal population was observed. The fungal population under the nonwoven mulch produced by viscose fibres was 161% higher in comparison to the control field. The available nutrient contents of soils under the nonwoven mulches were higher compared to the control field. The control field showed higher available nutrient contents of soil than the field covered by conventional agro foil.&#x0D; The results of the study reveal that usage of nonwoven mulches made of viscose fibres is most appropriate for short-term mulching application since successfully increases microbial population and improves the physio-chemical properties of soil.