Heavy Grains Research Articles

The Effect of Foliar Application of Azolla Liquid Organic Fertilizer on Growth and Yield of Rice in Swampy Soil

Rice cultivation faces challenges due to limited land availability despite increasing demand. Utilizing swamp land for cultivation presents an alternative, albeit hindered by difficult-to-control water conditions and less effective fertilizer spread. To ensure optimal nutrient supply, foliar application of Azolla liquid organic fertilizer (LOF) is explored. This study investigates the ideal concentration and frequency of Azolla LOF application for rice growth and yield. Employing a split plot design, the main plot assesses LOF concentration (3%, 6%, 9%, 12%), while the subplot evaluates application frequency (1, 2, 3 times). Results indicate that a 9% LOF concentration yields the highest tiller count (17.99), longest panicle (25.788 cm), highest grain count per panicle (158.2978), heaviest grain weight per hill (45.878 g), and highest grain weight per plot (3457.52 g). However, the fastest flowering period (54 DAP) occurs with a 12% LOF concentration. Applying Azolla LOF three times achieves the earliest flowering (55.25 DAP), while two applications yield the longest panicle (25.03 cm). Notably, no interaction is observed between LOF concentration and application frequency on rice growth and yield. These findings provide insights into optimizing Azolla LOF application for enhanced rice cultivation in swamp lands.

Integration of molecular breeding and multi-resistance screening for developing a promising restorer line Guihui5501 with heavy grain, good grain quality, and endurance to biotic and abiotic stresses.

Rice, a critical staple on a global scale, faces escalating challenges in yield preservation due to the rising prevalence of abiotic and biotic stressors, exacerbated by frequent climatic fluctuations in recent years. Moreover, the scorching climate prevalent in the rice-growing regions of South China poses obstacles to the cultivation of good-quality, heavy-grain varieties. Addressing this dilemma requires the development of resilient varieties capable of withstanding multiple stress factors. To achieve this objective, our study employed the broad-spectrum blast-resistant line Digu, the brown planthopper (BPH)-resistant line ASD7, and the heavy-grain backbone restorer lines Fuhui838 (FH838) and Shuhui527 (SH527) as parental materials for hybridization and multiple crossings. The incorporation of molecular markers facilitated the rapid pyramiding of six target genes (Pi5, Pita, Pid2, Pid3, Bph2, and Wxb ). Through a comprehensive evaluation encompassing blast resistance, BPH resistance, cold tolerance, grain appearance, and quality, alongside agronomic trait selection, a promising restorer line, Guihui5501 (GH5501), was successfully developed. It demonstrated broad-spectrum resistance to blast, exhibiting a resistance frequency of 77.33% against 75 artificially inoculated isolates, moderate resistance to BPH (3.78 grade), strong cold tolerance during the seedling stage (1.80 grade), and characteristics of heavy grains (1,000-grain weight reaching 35.64 g) with good grain quality. The primary rice quality parameters for GH5501, with the exception of alkali spreading value, either met or exceeded the second-grade national standard for premium edible rice varieties, signifying a significant advancement in the production of good-quality heavy-grain varieties in the southern rice-growing regions. Utilizing GH5501, a hybrid combination named Nayou5501, characterized by high yield, good quality, and resistance to multiple stresses, was bred and received approval as a rice variety in Guangxi in 2021. Furthermore, genomic analysis with gene chips revealed that GH5501 possessed an additional 20 exceptional alleles, such as NRT1.1B for efficient nitrogen utilization, SKC1 for salt tolerance, and STV11 for resistance to rice stripe virus. Consequently, the restorer line GH5501 could serve as a valuable resource for the subsequent breeding of high-yielding, good-quality, and stress-tolerant hybrid rice varieties.

Coma and tail of Comet 67P/Churyumov–Gerasimenko during the 2021–2022 apparition

ABSTRACT We present results on the global activity of comet 67P/Churyumov–Gerasimenko (67P), the ROSETTA target, during its first perihelion passage after the mission and after an encounter with planet Jupiter. 67P was observed by broad-band filter imaging at 33 epochs during 2021 May 21 to 2022 June 1. The mean radial flux profiles suggest that ‘equilibrium’ conditions for the dust flow in the coma existed from around perihelion until about 100 d thereafter. We propose a scenario for the smaller and larger radial exponents, measured before and after the ‘equilibrium’ phase. Four coma fans with possible source regions at +40°, –10°, –50°, and –70° latitude on the nucleus are identified. The three fans at southern latitudes may be identical with fan sources seen during post-perihelion in 2015–2016. The rotation axis of 67P may not have changed at all or at least not much (<5°) from the orientation measured during the Rosetta mission at the comet. The dust streamers in the coma originated from observed coma fans, containing mostly dust emitted within days to weeks before observation. Two dust streamers, a long- and a short-lasting one, contained heavy dust grains from emission periods hundreds of days before perihelion. Similar emission periods are obtained for the dust seen in the tail region of the comet. Similarities and differences in the dust activity during the recent apparition with that of the Rosetta mission at the comet are found.

Natural variation in MORE GRAINS 1 regulates grain number and grain weight in rice.

Grain yield is determined mainly by grain number and grain weight. In this study, we identified and characterized MORE GRAINS1 (MOG1), a gene associated with grain number and grain weight in rice (Oryza sativa L.), through map-based cloning. Overexpression of MOG1 increased grain yield by 18.6%-22.3% under field conditions. We determined that MOG1, a bHLH transcription factor, interacts with OsbHLH107 and directly activates the expression of LONELY GUY (LOG), which encodes a cytokinin-activating enzyme and the cell expansion gene EXPANSIN-LIKE1 (EXPLA1), positively regulating grain number per panicle and grain weight. Natural variations in the promoter and coding regions of MOG1 between Hap-LNW and Hap-HNW alleles resulted in changes in MOG1 expression level and transcriptional activation, leading to functional differences. Haplotype analysis revealed that Hap-HNW, which results in a greater number and heavier grains, has undergone strong selection but has been poorly utilized in modern lowland rice breeding. In summary, the MOG1-OsbHLH107 complex activates LOG and EXPLA1 expression to promote cell expansion and division of young panicles through the cytokinin pathway, thereby increasing grain number and grain weight. These findings suggest that Hap-HNW could be used in strategies to breed high-yielding temperate japonica lowland rice.

OsLCD3 interacts with OsSAMS1 to regulate grain size via ethylene/polyamine homeostasis control.

A fundamental question in developmental biology is how to regulate grain size to improve crop yields. Despite this, little is still known about the genetics and molecular mechanisms regulating grain size in crops. Here, we provide evidence that a putative protein kinase-like (OsLCD3) interacts with the S-adenosyl-L-methionine synthetase 1 (OsSAMS1) and determines the size and weight of grains. OsLCD3 mutation (lcd3) significantly increased grain size and weight by promoting cell expansion in spikelet hull, whereas its overexpression caused negative effects, suggesting that grain size was negatively regulated by OsLCD3. Importantly, lcd3 and OsSAMS1 overexpression (SAM1OE) led to large and heavy grains, with increased ethylene and decreased polyamines production. Based on genetic analyses, it appears that OsLCD3 and OsSAMS1 control rice grain size in part by ethylene/polyamine homeostasis. The results of this study provide a genetic and molecular understanding of how the OsLCD3-OsSAMS1 regulatory module regulates grain size, suggesting that ethylene/polyamine homeostasis is an appropriate target for improving grain size and weight.

Mechanical transport revealed by optical textures of heavy minerals in aeolian sand: A case study in the Badain Jaran Desert, Northwestern China

Determining whether and to what extent the relative abundance of heavy minerals in original detrital assemblage has been modified by mechanical transport is beneficial for understanding regional historical climate changes and acquiring modern sediment provenance information. Utilizing the frequency of surface mechanical optical textures of heavy minerals may be an effective approach to address this question. However, the connection between the frequency surface mechanical optical textures of heavy minerals and the variations in the relative abundance of these minerals remains uncertain. In this study, 12 modern aeolian sand samples were collected from the Badain Jaran Desert in hyper arid region of northwestern China, characterized by weak weathering to analyze their relative contents of five major heavy minerals. Then, 3796 transparent heavy mineral grains were photographed under the parallel light of a polarizing microscope, and the frequency of 13 surface mechanical optical textures were calculated. The results reveal that the variations in the relative abundance of heavy minerals are substantially influenced by mechanical transport. The decrease in the relative abundance of heavy minerals with weak mechanical stability primarily attributed to mechanical collision. Conversely, the variations in the relative abundance of heavy minerals with strong mechanical stability are primarily influenced by mechanical abrasion. Therefore, mechanical transport impact on the relative abundance of heavy minerals in regions with weak chemical weathering. Establishing heavy mineral characteristic indices for provenance studies using the relative abundance of mechanically unstable minerals may not directly indicate transport distance but rather the strength of wind forces, which have significant potential in palaeo wind regime studies. This study expands the research field of sediment surface micromorphology and has potential applications in inferring past climate changes and determining modern sediment provenance.

Characteristics of heavy metals in surface sediments of the Van Don-Tra Co coast, northeast Vietnam

Eighteen surface sediment samples were collected from the Van Don-Tra Co coast, northwestern Gulf of Tonkin, for analyzing the concentration of heavy metals (Zn, Cr, As, Cu, Ni, Pb, Co, and Cd) and grain size. The statistical and contamination indices of heavy metals were calculated to evaluate the extent of pollution caused due to heavy metals and their potential harm to the environment. According to the analysis results, the contamination of heavy metals in the study area were higher than the background concentrations, except for Pb. The heavy metal concentrations in the study area followed the descending order of Zn > Cr > As > Cu > Ni > Pb > Co > Cd. The concentrations of heavy metals do not correlate with clay content, and almost heavy metals were non-correlated with silt and sand contents, except for Cr, implying that the grain size does not control heavy metals concentration in surface sediments in the region. The results of pollution indices imply that the contamination in the environment was due to excess accumulation of Cd, in contrast to that of Zn. The ecological pollution risk shows an increased risk of heavy metal pollution. According to the statistical index, the contamination of heavy metals in surface sediments in the study area could come from the same sources under the same environmental conditions and is related to the source of sedimentary material from the mainland near the study area.

Design and Fabrication of Gravity Separator for Grains and Dust

Gravity separators are machines used to separate grains and dust by using the difference in weight between grains and dust. They work by causing grains to fall at different speeds, with heavier grains falling faster and lighter dust falling slower. The new gravity separator design is more efficient and effective than previous designs, making it easier to clean and maintain. It has the potential to revolutionize the separation process, saving businesses time and money. The new gravity separator is more effective at separating grains from dust and other impurities, improving the quality of food products and mined minerals. Additionally, it is also reducing waste.

A Relevant Characterization and Compatibility for Reuse the Sediments from Reservoirs in Southern Italy

The damming of watercourses results in sediment accumulation and, therefore, in the reduction of useful storage capacity. The storage capacity can be recovered through dredging, but this process generates large volumes of sediments that require proper management. To avoid landfilling and promote recovery operations, sediment characterization is the preliminary step to any assessment and decision. This paper presents the results of tests on sediments sampled at two reservoirs in southern Italy, the Camastra and the San Giuliano, in Basilicata. These investigations include testing of organic matter, heavy metals grain size distribution, and the assessment of the pollution degree. A lack of correlation between the sampling point and the heavy metal content was observed in sediments, except Be, Cr and Ni for the San Giuliano reservoir. This may be attributed to the presence of agricultural activities and fertilizer use in its watershed. Similarly, there is no dependence between the organic carbon and the grain size distribution, the former being scarcely found in both reservoirs (on average 0.91% for the Camastra sediments and 0.38% for the San Giuliano sediments), the latter being predominantly characterized by sandy matrices downstream of the reservoirs (on average 64.3% ± 32.9%) and by silty-clayey matrices in the upstream areas (on average 65% ± 14.3%). Finally, the determination of the single pollution index Pi and the Nemerow integrated pollution index PN highlights that sediments are not contaminated with heavy metals. Most of them show values of the indices above between 0 and 1 (“unpolluted”) and, in a few cases, values between 1 and 2 (“poorly polluted”). The findings suggest that these sediments can be reused for environmental and material recovery, using them as secondary raw materials for sub-bases and embankments, for filling in disused quarries, for reprofiling and reconstructing the morphology of coastlines or riverbeds, for beach nourishment and in the agronomic and construction industry fields.

Provenance of Beach Sands in the Northern Gulf of Guinea, SW Cameroon

Abstract Petrographical, mineralogical and geochemical studies were carried out on the beach sands of Limbe (South-West Cameroon) to highlight their provenance, source rocks alteration and the tectonic framework. The Limbe beach sediments were classified as sandy litharenite type. The sediments were derived from mafic and andesite source rocks. The sediments are composed of quartz, olivine, augite, amphibole, pyroxene, plagioclase, potassium feldspar, muscovite and biotite, indicating the primary phases of magmatic source rocks; kaolinite and illite in the secondary phase; and rutile in their residual composition. The presence of ferromagnesian minerals indicates that they were derived from the mafic rocks, which are the basalts of the Cameroon Volcanic Line (CVL). However, the presence of quartz associated with plagioclase and feldspars suggests that alkaline granites played a minor role in the sedimentation of the Limbe beaches. Total Quartz - Total Feldspar - Total Lithic Fragments (Qt-Ft-Lt) mineralogical relationships demonstrate that these beach sediments would be formed in an undissected arc tectonic context, typical of volcanic sources with high relief producing black sands or sands enriched in iron oxides. Their microscopic characteristics of angular to subangular shapes suggest that the magmatic sources are proximal to the shoreline deposits. The characteristics of microporosity, iron oxide inclusions, conchoidal fracture, heavy mineral grains, and opaque minerals support this proximal source. The conchoidal fractures defining the angularity of these beach sediments would suggest its derivation from crystalline rocks. The predominance of heavy minerals suggests that the rocks proximal to the beach have been altered. The abundance of primary minerals associated with these secondary heavy minerals justifies the existence of unweathered lithic grains in the source rocks and an alteration that occurred under a tropical monsoon climate that ranged from semi-humid to humid. The use of the multi-element tectonic discrimination diagram implies an arc framework that is compatible with the geology of the study area.

Reproductive Development and Yield Components of Bario Sederhana Rice in Response to Photoperiod

A series of controlled environment treatments were conducted to quantify reproductive development and yield components of Bario Sederhana rice grown under five photoperiod regimes (8, 9, 10, 11, & 12 h). A ‘broken-stick’ linear regression of heading rate against photoperiod was used to determine the cardinal photoperiods for heading. The reproductive development towards photoperiod showed a delayed pattern in time to heading, anthesis, and maturity under lengthening photoperiod from 10 to 12 h. For example, under 10 h photoperiod the crops required 1680 °Cd (70.8 days) from emergence to heading but took an extended duration of 3147 °Cd (132.6 days) when they were sown at 12 h photoperiod. The prolonged time taken for reproductive development modified by photoperiod resulted in higher yield components. This is because the lengthening time from heading to maturity extended the duration of grain filling. The longest photoperiod of 12 h gave the highest percentage of filled spikelets (65.3%) thus consequently leading to the heaviest grain weight of 1.4 g per panicle. The base, optimum, and maximum photoperiod for heading were estimated to be 7.4 h, 10 h, and 14.8 h, respectively.

Mineral exploration using trace element composition of pyrite grains from till: A case study from the Petäjäselkä Au occurrence, northern Finland

Geochemical anomalies and indicator mineral studies in glacial sediments are commonly used to define mineral exploration targets in glaciated areas. Trace element composition of sediment-hosted heavy minerals, such as pyrite and chalcopyrite, can be potentially used to fingerprint mineral deposits. This study presents results from trace element compositions of pyrite in the heavy mineral concentrates of till and mineralized bedrock samples from the orogenic gold ore occurrences in the Petäjäselkä area, Central Lapland belt, northern Finland.The trace element contents of pyrite grains were evaluated by using a robust compositional data analysis workflow, including symmetric pivot coordinates and robust principal component analysis (PCA). Four different pyrite textures (A-D) were identified from the gold ore occurrences. Compositional data analysis showed that the heavy mineral pyrite correlated with Pyrite D in the ore occurrence and confirmed the discrimination power of pyrite in the heavy mineral grains as a tool for source characterization of transported sedimentary material. The study also discusses the difficulties of finding suitable grains for the LA-ICP-MS, highlighting the importance of proper heavy mineral grain recovery procedures and the factors of oxidization and weathering processes influencing the geochemical compositions of the pyrite grains.

Performance of Seed Rate on Wheat Crop (Triticum aestivum L.) under Late Sown Condition

A study was conducted to investigate the “Performance of seed rate on wheat crop (Triticum aestivum L.) Under late Sown Condition.” This experiment was carried out during the Rabi seasons of 2018-2019 and 2019-2 020 at the Pili-Kothi Student Research Farm and in the Laboratory Department of Agronomy at T.D.P.G. College Jaunpur. Increasing seed rates demonstrated a significant influence on various growth parameters, including initial plant population, shoot numbers, plant height, and dry matter production, with the highest values consistently observed at 140 kg/ha. In terms of yield-contributing characteristics, the 140 kg/ha seed rate led to increased spike counts, longer spikes, more grains per spike, and heavier grains. Yield significantly favored the 140 kg/ha rate, averaging 4.25-4.21 Mg/ha, surpassing the 120 kg/ha rate (4.08-4.07 Mg/ha) and markedly exceeding the 100 kg/ha rate (3.85-3.84 Mg/ha). The straw and biological yields further echoed this trend, cementing the prominence of the 140 kg/ha seed rate in augmenting late-sown wheat productivity.

Physiological Properties of Perennial Rice Regenerating Cultivation in Two Years with Four Harvests.

Crop perennialization has garnered global attention recently due to its role in sustainable agriculture. However, there is still a lack of detailed information regarding perennial rice's regenerative characteristics and physiological mechanisms in crop ratooning systems with different rice stubble heights. In addition, the response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice remains poorly documented. Here, we explored the regenerative characteristics and physiological mechanisms of an annual hybrid rice, AR2640, and a perennial rice, PR25, subjected to different stubble heights (5, 10, and 15 cm). The response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice were also investigated. The results show that PR25 overwintered successfully and produced the highest yield, especially in the second ratoon season, mainly due to its extended growth duration, higher number of mother stems, tillers at the basal nodes, higher number of effective panicles, and heavier grain weight when subjected to lower stubble heights. Further analysis revealed that PR25 exhibited a higher regeneration rate from the lower-position nodes in the stem with lower stubble heights. this was primarily due to the higher contents of phytohormones, especially auxin (IAA) and gibberellin (GA3) at an early stage and abscisic acid (ABA) at a later stage after harvesting of the main crop. Our findings reveal how ratoon rice enhances performance based on different stubble heights, which provides valuable insights and serves as crucial references for delving deeper into cultivating high-yielding perennial rice.

GW9 determines grain size and floral organ identity in rice.

Grain weight is an important determinant of grain yield. However, the underlying regulatory mechanisms for grain size remain to be fully elucidated. Here, we identify a rice mutant grain weight 9 (gw9), which exhibits larger and heavier grains due to excessive cell proliferation and expansion in spikelet hull. GW9 encodes a nucleus-localized protein containing both C2H2 zincfinger (C2H2-ZnF) and VRN2-EMF2-FIS2-SUZ12 (VEFS) domains, serving as a negative regulator of grain size and weight. Interestingly, the non-frameshift mutations in C2H2-ZnF domain result in increased plant height and larger grain size, whereas frameshift mutations in both C2H2-ZnF and VEFS domains lead to dwarf and malformed spikelet. These observations indicated the dual functions of GW9 in regulating grain size and floral organ identity through the C2H2-ZnF and VEFS domains, respectively. Further investigation revealed the interaction between GW9 and the E3 ubiquitin ligase protein GW2, with GW9 being the target of ubiquitination by GW2. Genetic analyses suggest that GW9 and GW2 function in a coordinated pathway controlling grain size and weight. Our findings provide a novel insight into the functional role of GW9 in the regulation of grain size and weight, offering potential molecular strategies for improving rice yield.

Enhancing coercivity and mechanical strength of sintered Nd-Fe-B magnets by heavy rare earth-free grain boundary diffusion

In addition to magnetic properties, mechanical strength is also an important factor in the stability of Nd-Fe-B magnets during service. Here, we proposed a strategy to simultaneously enhance magnetic and mechanical properties by grain boundary diffusion (GBD) without using heavy rare earths (HRE). For a 4.5 mm thick sintered magnet, the coercivity of Pr70Al20Cu10 and Al75Cu25 (at.%) diffused magnets can enhance from 1000 to 1346 and 1089 kA/m, respectively, due to the formation of continuous grain boundary (GB) layers for magnetic decoupling, respectively. The increased compressive strength and surface hardness of the magnet mainly result from the enhanced connection between 2:14:1 grains. Since the diffusion of HRE-free alloys improves GB phase by both increasing the wettability of GB phase and reducing the defects at the interface of 2:14:1 phase, more energy is required for the crack propagation which results in an increase in mechanical properties. Furthermore, this work generalizes the difference between the HRE and non-HRE diffusion sources in enhancement mechanisms of coercivity and mechanical strength. It is thus believed that GBD can be used to improve not only magnetic properties but also the other properties of magnets.

REALISATION OF PRODUCTIVITY POTENTIAL AND GRAIN QUALITY BY VARIETIES OF SPRING WHEAT OF DIFFERENT MATURITY GROUPS

In the Middle Trans-Urals, on less fertile derno-medium-podzolic loamy soils with limited growing seasons, a comparative trial of spring wheat varieties from three maturity groups was conducted over four years. It was established that early-maturing, mid-early, and mid-season spring wheat varieties can produce good yields, grain, and seed quality. The realisation of the genetic potential of productivity and grain quality of types is primarily influenced by abiotic conditions, the unfavourable course of which is not always correct with technological practices. In terms of grain yield over three years, among mid-early varieties, the Kalinka variety stood out, and among mid-season varieties, the Chernozemnyural'skaya 2 variety, with results of 243 and 266 g/m2, or 2.43 and 2.66 t/ha, respectively. Under favourable growth and development conditions, grain yields of early, mid-early, and mid-season varieties exceed 5 t/ha. Regional conditions allow grain protein content to generally exceed 23.0%, meeting the requirements of classes I–III, and gluten quality meeting the needs of groups I–II. The quality of spring wheat grain is determined to a greater extent by the prevailing abiotic conditions rather than the genetic characteristics of the variety. The requirements for forming spring wheat grain do not promote the formation of heavy grains; the 1000-seed weight usually amounts to around 30 g. Grain yields produced by early, mid-early, and mid-season group varieties are typically characterised by high laboratory germination values (over 92 %).

A study on seasonal dynamics of heavy mineral distribution and surface micro-textures of Beach sediment from Govindampalli – Durgarajupatnam Coast, East Coast of India

The main objective of this research is to investigate the distribution, concentration, and surface micro-textures of heavy minerals in beach sediments from four micro-environments: dune, backshore, berm, and foreshore. A total of forty-eight samples (twenty-four samples in each season) were collected along the Govindampalli (GP) to Durgarajupatnam (DP) Coast on the east coast of India, covering the pre-monsoon and post-monsoon periods from June 2016 to December 2016. The study revealed significant heterogeneity in beach sediment properties, heavy mineral distribution, and concentrations. Heavy mineral analysis was conducted on the coarse (+60), medium (+120), and fine (+230) fractions of the beach sediment. The analysis of weight percentage (wt%) demonstrated that a higher proportion of heavy minerals was associated with the fine fraction (+230) compared to the coarse and medium fractions at all stations. Opaque minerals, garnets, zircons, and monazites were found in promising quantities along the coast. The total concentrations of heavy minerals were higher during the pre-monsoon season compared to the post-monsoon season. The surface micro-textures of heavy mineral grains from various stations in the study area were primarily influenced by mechanical and chemical processes occurring on the grain surfaces. These micro-textures indicated significant mechanical influences at the estuary point and moderate to high wave energy in the beach deposits.

Effect of Severe Shot Peening on Mechanical Properties and Fatigue Resistance of Wire Arc Additive Manufactured AISI 316L

The wire arc additive manufacturing (WAAM) technology has become very popular recently. However, the properties of printed pieces are not yet examined properly. In this paper the effect of severe shot peening (SSP) on mechanical properties of wire arc additive manufactured AISI 316L is investigated. The effect of SSP on the surface hardness of the WAAM 316L is investigated by performing microhardness measurements. Changes to the surface microstructure caused by SSP are evaluated in the EBSD investigation. The effects of SSP on tensile and fatigue strength are investigated experimentally. The EBSD analysis showed that there has been remelting of each printed layer due to the heat input from the next printed layer, and heavy epitaxial grain growth was present in the microstructure. This led to coarse columnar grain structure. Investigation of deformed SSP surface layer indicated that the main deformation type was either conventional dislocation glide or twinning. This meant that no martensite formation was present on the surface. The SSP increased the surface hardness of WAAM printed 316L by 225% and the hardened layer was 0.4 mm thick. The SSP improved the yield strength of WAAM 316L by 34%. The SSP significantly improved WAAM 316L fatigue resistance in both low-cycle and high-cycle regime.

Effect of different fertilizer types on three millet crops grown in the humid tropics of Nigeria

Northern Nigeria is predominantly known to produce millet due to the low rainfall associated with the climate. However, Changes in climatic factors over the years has resulted in the shift in crop production as some crops that were adaptable to the semi-arid regions become increasingly adaptable to tropical rainforest regions. Hence there is the need to study millet in the humid tropics of Nigeria. The objectives of the studies was to determine the performance of 3 millet types treated with different fertilizers types in the humid tropics of Nigeria. The experiment was conducted in the Department of Crop Science Screen-house situated at the Research and Teaching Farm of the Faculty of Agriculture, University of Benin, Benin City. The experiment was a 3 x 6 factorial set up in a completely randomized design which includes 3 millet crop types (Gero, Maiwa and Tamba) and 6 fertilizer types (Abuscular mycorrhiza (AM), Trichoderma hazianum (TH), NPK (15:15:15; 60 kg/ha), AM+NPK (15:15:15 at 30 kg/ha), TH+NPK and Control (C)). Growth and yield variables were measured every 3 weeks for 12 weeks and the data obtained were subjected to analysis of variance. Means were separated using Fishers-protected LSD at 5% level of probability. Millet types were significantly different with Gero and Maiwa having higher mean performance over Tamba millet. However, Gero millet was the only plant to attain flowering and subsequent grain yield during the period of the study. The fertilizer types were significant only on yield and yield components. Grain yield of Gero millet with TH+NPK had the highest yield (>100g plant-1) and wider grain diameter (>2.0 mm) than other fertilizer types. AM fertilized plants had the heaviest grain weight and was significantly heavier than the grains obtained from plants in control pots. Millet types can be grown in the humid tropics of Nigeria under controlled condition as observed in the study. They can grow vegetatively with little or no fertilizer, but the grain yield could be enhanced with Abuscular mycorrhiza and Trichoderma hazianum as biofertilizers in combination with NPK fertilizer. Application of this finding will reduce the amount of inorganic fertilizer that will be solely required for millet production by 50% and consequently promote environmental sustainability. Under controlled conditions, Gero millet can be cultivated for both forage and grains whereas Maiwa and Tamba millets could be cultivated for forage in the humid tropics of Nigeria.