Row Distance Research Articles

Technical evaluation of transplanters' performance for potted seedlings

This research was conducted to evaluate the performance of disc, carrousel and dibble-type transplanters for potted tomato and watermelon seedlings in field conditions. Intra row distance, transplantation depth, the gripping force of seedlings to the soil, vertical position, damage of seedling and seedling survival rate were determined to evaluate performance of transplanters. The disc and carrousel-type transplanters place the seedlings into furrow and the dibble-type transplanter places the seedlings into the holes. According to field experiment results, distribution uniformity of intra row distance of dibble and carrousel-type transplanters were very well with the coefficient of variations between 3.52% and 5.55%. The highest transplantation depth was obtained when the carrouseltype transplanter was used. The disc and carrousel-type transplanters placed the seedlings into furrow, increasing the gripping force between seedlings and soil. The angle between the seedlings and vertical plane was under the 30° for all transplanters used. Only the disc-type transplanter damaged seedlings over 3%. The survival rate of seedlings for all transplanters were higher than 90% and this rate is acceptable for transplanting vegetable seedlings.

Field Response of Brassica Germplasm against Alternaria Leaf Spot Disease and its Management

Brassica is an edible oilseed crop and world’s third most important oilseed source. Alternaria leaf spot disease of Brassica, caused by Alternaria brassicae (Berk) is major limiting factor for its yield loss. In current study forty-two Brassica germplasm (B. napus = 17, B. juncea = 25) were evaluated against Alternaria leaf spot disease at research area of Plant Pathology Research Institute (PPRI), Ayub Agricultural Research Institute (AARI), Faisalabad, Pakistan. These germplasms were sown in augmented design with 10 cm plant x plant and 60 cm row x row distance in single replication. A susceptible check KJ-159 was sown after every two entries. Data were recorded on 0-9 disease severity rating scale. Out of 17 germplasm of B. napus no germplasm was found to be immune. Two germplasm exhibited highly resistant while eight germplasm showed resistance response against the disease. Six germplasm were moderately resistant and only one showed moderately susceptible response. Similarly, out of 25 germplasm of B. junceas even were found moderately resistant and ten showed moderately susceptible response. Seven were susceptible while only one germplasm was highly susceptible. Then in-vitro efficacy of different fungicides was evaluated against A. brassicae. For evaluation of fungicides Potato Dextrose Agar (PDA) amended with five different fungicides at different concentrations (10, 50, 100 and 200 ppm) was used. Experiment was conducted in completely randomized design with ten replications. Data were recorded on mycelial growth (mm) of fungus. Mancozeb (Ethylene bisdithiocarbamate) and Nativo (Tebuconazole) significantly inhibited the growth at all concentrations while Antracol (Propineb) was significantly least effective against A. brassicae. The current research provided the new resistance source of Brassica germplasm to the breeders against Alternaria leaf spot disease and its management.

Matching crop row and dripline distance in subsurface drip irrigation increases yield and mitigates N2O emissions

Intensive irrigation and nitrogen (N) fertilization are often linked to low N-fertilizer efficiency, and to high emissions of the greenhouse gas nitrous oxide (N 2 O). Efficient irrigation systems (e.g. subsurface drip irrigation [SDI]) combined with N-fertigation in a no-till agroecosystem can promote N-use efficiency, thereby curbing N 2 O emissions without depressing crop yield. Yet, crop type and SDI plant settings (and management) such as dripline spacing may determine the agronomic and environmental performance of SDI. In this two-year field study on maize ( Zea mays L.) - soybean ( Glycine max [L.] Merr.) rotation with conservation agriculture management (no-till and cover crops), we investigated the effects of three different irrigation/fertilization systems (SDI with a narrow dripline spacing (70 cm) + fertigation with ammonium sulphate, SDI with a large dripline spacing (140 cm) + fertigation with ammonium sulphate, and sprinkler irrigation [SPR] + granular urea application) on yield, N-fertilizer efficiency, and N 2 O emissions in a fine-textured soil. We hypothesized that SDI systems (especially with narrow dripline distance) would increase yield and mitigate N 2 O compared with SPR, and particularly for maize due to its higher water and nutrient demand. We found that SDI increased maize yield (+31%) and N-fertilizer efficiency (+43–71%). These positive results were only observed during the drier year in which irrigation supplied ca. 80% of maize water requirements. The narrower dripline spacing mitigated N 2 O emissions compared with sprinkler irrigation (by 44%) and with the wider spacing (by 36%), due to a more homogeneous distribution of N in soil, and to a lower soil moisture content. Soybean yield and N-use efficiency were not affected by the irrigation systems. We also found that SPR enhanced cover crop residue decomposition, thus promoting the release of C and N into the soil and increasing N 2 O emissions. Overall, our study provides important insights on key management decisions that define the sustainability of novel irrigation systems; in particular SDI with a 70 cm dripline distance should be promoted for maize to increase productivity and decrease N 2 O emissions in fine-textured soils. • Benefits of SDI increases with high water and N demanding crops. • SDI increases maize yield and N-fertilizer efficiency during dry years. • Narrow dripline distance (0.70 m) mitigates N 2 O emissions. • N release from litter decomposition may play a major role in N 2 O emissions.

Experiment and design approach of steel-to-laminated bamboo lumber screwed connections under load parallel to grain

As a new type of green building material, laminated bamboo lumber (LBL) has attracted more and more attention in the field of civil engineering. Dowel connections is one of the most significant connection methods for LBL, in which screw has the advantages of low cost and simple installation. This paper experimentally investigates screwed connections with LBL as main members and steel plate as side members, in which the effects of screw diameter, anchorage depth, end distance, center-to-center distance and row distance are studied. 45 single-screwed connection specimens were tested by symmetrically configured lateral resistance tests and 2 failure modes of screw pull-out and screw cut-off were observed, corresponding to 2 yield modes of screws. 18 double-screwed connection specimens were tested to propose design recommendations to avoid brittle failure between screw holes in LBL. Then the test results were compared with the predicted values calculated by NDS-2018, Eurocode 5 and GB/T 50005-2017. Based on the assumption of ideal elastoplastic model, a theoretical formula was derived and verified by test results. Besides, experimental load-slip curves were compared with those of Foschi model, which showed that Foschi model can be used to predict load-slip curves under the appropriate relative stiffness between fasteners and members. This research provides a scientific basis and favorable information for the engineering design and applications of LBL structures with screwed connections.

Research on the Stability of Anti-Slip Pile Support Structures for Railway Pile Slopes

The accumulation slope is widely distributed in the mountainous area of China; this paper takes the slope of the Chengdu–Lanzhou Railway as the engineering background and analyzes the stability of the slope and the mechanical properties of the anti-slip pile under symmetrical train loads. First, the finite element software Midas GTS NX was used to analyze the effect of the slope after the anti-slip pile support and the stability of the slope at different pile spacings, pile row distances, and pile positions. Then, the finite element analysis results of the pile-side earth pressure and landslide thrust were compared with those of earth pressure theory, the standard method, and field-measured data. The results of this paper are as follows: (1) The anti-slip pile support increased the slope stability coefficient from 1.175 to 1.680. (2) The slope stability gradually decreased with increases in anti-slip pile spacing and pile row distance and rose first and then decreased with an increase in pile position. (3) The active earth pressure values behind the pile by Coulomb theory were slightly smaller than the finite element analysis result; the theoretical values of the passive pressure before the pile were much larger than the finite element analysis results. (4) The landslide thrust was calculated by the transfer coefficient method when the safety factor K = 1.00. The results of explicit method and implicit method were the same, which were 8–19% higher than the finite element simulation value; when the safety factor K = 1.35, the theoretical value of the explicit method was about three times the simulated value, and the theoretical value of the implicit method was about 2.3 times the simulated value. (5) The measured values verified that the simulated values had a certain degree of reliability, and the relative deviation between the two was 5–17%.

The frequency of spring harvest and row distance affect the seed and forage production of alfalfa (Medicago sativa L.) under irrigated Mediterranean conditions

Aim of study: The effect of the number of spring harvests (1 or 2) for forage before letting alfalfa (Medicago sativa L.) grow for seed, combined with three different row distances, on seed production was evaluated over a three-year period. Area of study: Irrigated Mediterranean environment (NE Spain). Material and methods: Seed yield, forage production and seed weight were evaluated, as well as final plant stands and the economic implications of different decisions. Main results: The study revealed significant differences (p < 0.01) in seed yield between the number of forage harvests prior to letting the crop grow for seed in two of the three years of the study, with an overall average of 500 kg ha-1 for one spring harvest and 450 kg ha-1 for two spring harvests, but with significant differences associated with row distance in two of the three years. The average annual production of forage was 8.08 Mg of dry matter (DM) ha-1 for the case of two spring harvests and 7.57 Mg for one, with significant differences in one of the three years. Row distances of 20, 40 and 60 cm did not significantly affect forage DM production although, on average, higher forage yields were achieved with narrow row distances. From an economic point of view, our results suggest that the 1-harvest treatment before letting alfalfa grow for seed is slightly more profitable than the 2-harvest treatment (higher gross margin of about 54.5 € ha-1). Research highlights: Under irrigated Mediterranean conditions, alfalfa harvested only once in spring before letting the crop grow for seed production maximizes the gross margin.

Refining Fertilizers Rate Recommendation for Wheat (Triticum aestivum) at Kafa Zone Adiyo Wereda

To refining the effect of different fertilizers NPKS with common Zn and B has significant higher yields in each fertilizer levels on wheat, an experiment were conducted at Adiyo Wereda Kaffa Zone. The experiment was laid out in simple randomized complete block design having three replications. Plot size of 9m2(3 m x 3 m), seed rate of 150 kg ha -1 and row to row distance of 20 cm was used. Various combinations of each fertilizers N (0, 46, 92,138,176 and 222 kg ha -1 with 69p 2 o 5 ,80k 2 o,30s,2 Zn and 1B), P (,0,23 ,46,69,92and115 kg ha -1 with 92N,90k 2 o,30s,2 Zn and 1B), K (0,18,36,54,72and 90 kg ha -1 with 92N,69p 2 o 5 ,30s,2 Zn and 1B) and S (0,10,20,30,40 and 50 kg ha -1 with 92N,69p2o5,90k2o,2Zn and 1B with additional treatments, control and recommended NP in each fertilizers were used. N=urea; P=TSP; K= KCl; S= CaSO 4; Zn=ZnSO 4 ; B = Borax were used as a sources of NPKSZnB. Recommended rates of NP (64:20 kg ha-1) were applied. Nitrogen was applied in two split doses half at sowing and half about 35-45 days after sowing. Variety Digalo was used during the experiment. Plant height, Spike length, Grain yield and biomass were significantly affected by different fertilizers levels. Grain Yield significant at different fertilizer levels 176 N kgha -1 (3400.3kgha -1 ), 115P kgha -1 (4221.2 kgha -1 ), 90K kgha -1 (4128.9 Kg ha-1) and 40S kgha -1 (3987.0 kgha -1 ) were produced respectively in the interaction of ZnB. Based on the results, it is recommended a combined application of NPKS (176 kg N ha -1 ,115 kg P ha -1 , 90 kg K 2 O ha -1 and 40 kg S ha -1 with 2kg Zn ha -1 and 1kg B ha -1 ) fertilizers to achieve sustainable bread wheat production on the study area. Keywords: fertilizer rates, wheat DOI: 10.7176/FSQM/120-03 Publication date: October 31 st 2022

Enovoltaics: Symbiotic integration of photovoltaics in vineyards

In this study, we propose the symbiotic integration of photovoltaic (PV) systems into previously built vineyards structures, so as to reduce land intervention, visual impact and costs while suppressing impact over crop production and quality. For this purpose, we have identified grape trellises as an ideal crop type to implement this concept based on a simulation study that analyzes the shading patterns and the PV energy generation of different PV design configurations using Photovoltaic Geographical Information System’s solar radiation data and system performance tool. Our proposal consists in the vertical integration of photovoltaic surfaces over the vines, using the same trellis structure, therefore minimizing cost and land building. We found that a ratio between row distance and trellis height equal or greater than 1.5 allows for the PV integration without generating significant shadowing between consecutive lines, while vertical orientation of the panels allows complete irradiation to the plants below. Different module configurations have been proposed and evaluated, resulting in a range of 40–60% installable capacity (compared to a ground mounted installation) with negligible shadowing over the leaves and grapes. Land equivalent ratio for the proposed architectures ranges between 1.27–1.50, therefore confirming the viability of this proposed agrivoltaic solution.

3D printing of alginate/thymoquinone/halloysite nanotube bio-scaffolds for cartilage repairs: experimental and numerical study.

One of the newest advances in 3D printing is the printing process of bio-scaffolds. The 3D printing of true materials for cartilage repairs accelerates cell growth and proliferation. In this study, a novel biomaterial was developed for the 3D printing of cartilage scaffolds composed of alginate, thymoquinone and halloysite nanotube. Calcium chloride was used as a cross-linker to form hydrogels. Experimental and numerical studies such as scanning electron microscopy, experimental tensile tests, and compression tests, chondrocyte cell seed, and MTT assay were also done. According to the results, alginate and halloysite nanotube increased the printing quality and mechanical performance of biomaterials. Tensile strength in bio-ink with the 30mg/ml of alginate, 40mg/ml of halloysite nanotube with 5% of thymoquinone increased up to 372 ± 42kPa, while compressive stress reached 894 ± 39kPa. Numerical results indicated that tensile and compressive properties of the scaffold structure depend on the space between printed rows. The best structure was obtained when the distance of rows was chosen at 0.4mm, and the nozzle diameter was 0.3mm. Finally, the biomaterial with the 30mg/ml of alginate, 40mg/ml of halloysite nanotube with 5% of thymoquinone showed a high mechanical and biological performance, compared to pure alginate bio-scaffolds. Biomaterials included alginic acid sodium salt/thymoquinone/halloysite nanotube mixed and 3D printed in high technology bioprinter, then mechanical and biological properties of printed bio-scaffolds obtained by different experimental tests.

P16. Biomechanical assessments of the spine during a 2000M ergometer row test

<h3>BACKGROUND CONTEXT</h3> Ergometer rowing has gained popularity as a "low-impact" form of exercise. Lumbar spine injuries are the most common injury in rowers. Previous studies have shown ergometer training to be associated with an increased risk of injury. Muscular fatigue and spine range of motion may correlate to pain or injury in ergometer rowing. <h3>PURPOSE</h3> The purpose of the present study is to utilize 3D motion capture and electromyography (EMG) assessments to 1) evaluate how muscular activation relates to lumbar spine mechanics; 2) determine the impact of fatigue on back muscle activation and biomechanics. <h3>STUDY DESIGN/SETTING</h3> Prospective analysis. <h3>PATIENT SAMPLE</h3> Seventeen rowers (M=8, F=9) with a mean age of 38 ± 9.1 years and a VO2 max of 44.4 ± 7.8 ml·kg·min-1. <h3>OUTCOME MEASURES</h3> Pull force, kinematics and muscle activation were recorded at 200m, 600m, 1000m, 1400m and 1800m distances. Spine flexion (degrees) was investigated. <h3>METHODS</h3> Seventeen rowers (m=8, F=9; age=38±9.1 years, VO2max=44.4±7.8 ml·kg·min-1) participated and performed a 2000-meter row on an ergometer. Pull force, kinematics and muscle activation were recorded using a load cell, motion capture system and a wireless EMG, respectfully. Data was recorded at 200m, 600m, 1000m, 1400m and 1800m distances. Spine flexion was calculated at three points in the sagittal plane and labeled as upper-, mid- and lower-spine. A mixed-model ANOVA repeated on row distance and a Tukey's post-hoc test was used to compare biomechanical assessments. Type-I error was set at a=0.05. <h3>RESULTS</h3> Average time to complete the test was 8.4 ± 1.0 min. Trapezius and mid-spinal erector activation was maintained through the row. A steady decrease in mean and peak latissimus dorsi activation was observed with increasing distance (p < 0.05), paired with an increase in peak lumbar spinal erector activation (p < 0.05), indicating fatigue of the upper back musculature followed by compensatory reliance on low back muscles to maintain/increase force. Upper spinal flexion (min and max) increased by 1000m, indicating an increase in the overall state of flexion with progressing distance (p < 0.05). Mid-spinal flexion demonstrated increased min flexion (indicating reduced peak extension) beginning at 1400m (P < 0.05). Lumbar spine flexion was maintained throughout the row, indicating that the primary mechanics fatigue change was a result of upper back rounding due to upper back muscle fatigue. Results indicate that low back pain and injuries associated with rowing may not be because of altered flexion/extension of the lumbar spine but rather, a result of increased workload placed on low back musculature to compensate fatiguing muscles and changes in the row mechanics of the upper and mid spine. Although ergometer rowing is often considered "low-impact," given the high number of contractions over a short time (<10min), it may be advisable for rowers to avoid multiple days of fatiguing row ergometer training per week. <h3>CONCLUSIONS</h3> The present findings will provide greater insight into the potential mechanisms of fatigue during ergometer rowing. Results will also give medical professionals a better understanding of the origins and presentation of soft tissue injuries in the spine in recreational rowers. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Evaluation of oat accessions for different agronomic traits under agro-climatic conditions of narc Islamabad

Oat is one of the most commonly planted forages and a significant component of crop rotation in a farming system. Keeping in view the importance of oat crop, seven oat accessions were evaluated at National Agriculture Research Center, Islamabad during Rabi season 2020-21. Randomized complete block design with three replications with row to row distance 30 cm was maintained for sowing the aforementioned oat accessions. Significant variation was observed for all the studied traits except plant height and leaves tiller-1. Highest mean values were observed for Jasper and Local Saryab for number of tillers plant-1 whereas Jasper was found to have maximum values for leaf area tiller-1 and leaf area index as well. Maximum flag leaf area was displayed by accession PP2-LV65 while the highest plant height was achieved by accession Local DIK. Maximum leaves tiller-1 was exhibited by S. 2000 while Local T.Jam achieved maximum green fodder yield and maximum dry matter yield t/ha. On the basis of high values for green fodder and dry matter yield Local T.Jam can be used for onward use for variety development.

Assessment of Genetic Diversity in Rice (Oryza sativa L.) Genotypes for Grain Yield Characters

A set of 55 genotypes of rice were evaluated for “assessment of genetic diversity in rice genotypes for grain yield characters”. The experiment was conducted in a Randomized Block Design with three replications during the kharif season, of 2021 at Naini Agriculture Institute, Naini. The plant to plant distance was 15 cm and row to row distance was 20 cm. The data were recorded from five randomly selected plants for each genotypes from all the replicates for thirteen characters. Analysis of variance showed significant differences among genotypes for all 13 characters indicating that the material has adequate genetic variability to support the breeding programme for improving the grain yield of rice. Out of 55 rice genotypes evaluated for various characters, 5 genotypes were found superior for different characters. These 5 genotypes were found better for more than one character. Among the lines SHUATS DHAN -6 (62.133g) recorded the highest grain yield per hill followed by the genotypes BPT-3291 (51.8g), SHIATS Dhan -2 (51.467g), SIGNET-5455 (50.467g) and SIGNET-5455 (50.4). All these genotypes were significantly higher as compared to the check NDR - 359 (CHECK) (22.67g). High estimate of heritability coupled with high genetic advance as percent of mean was recorded for Grain yield per hill, Biological yield, Number of spikelets per panicle, Harvest Index, Flag leaf length, Number of tillers per hill, Number of panicles per hill, Flag leaf width, Test weight, and Plant height. These traits are governed by additive gene effects and therefore, may be improved through direct selection. Further the characters viz., Biological yield, Harvest Index, Number of tillers per hill, Days to fifty percent flowering, Flag leaf length and Test weight, had the highest direct positive effect and indirect effect (through each other) on grain yield per hill. Thus, selections for these characters will prove efficient for the improvement of grain yield of rice. All the 55 rice genotypes were classified using Mahalanobis D2 statistics involving 13 quantitative characters of 55 genotypes grouped into 6 clusters In the present study, the highest inter cluster distance was observed between cluster IV and cluster V (368.37) followed by cluster II and cluster V (361.04).

Soybean performance under moisture limitation in a temperate tree-based intercropping system

CONTEXTTree-based intercropping (TBI) systems show promise in reducing the vulnerability of field crops to increasing water stress. TBI can generate several above- and belowground interactions between trees and crops. These interactions remain poorly documented, especially in the context of moisture limitation. OBJECTIVEThe objective of this study was to determine the performance of soybean within a TBI system under moisture limitation. We hypothesized that TBI generates both positive (near the alleyway centre) and negative (near the trees) effects on soybean performance and that these effects are accentuated when moisture availability decreases. METHODSA partial rainfall interception treatment (50% of the soil surface) in a soybean crop (stages R1 to R7) was installed for two years (2018 and 2019) in a TBI (50 trees/ha planted in 2012) in southern Quebec. TBI was composed of hybrid poplars (Populus deltoides × P. nigra) and different high-value hardwood species that were planted alternately within rows. A tree root-pruning treatment was also applied to understand belowground effects of tree roots on soybean growth under moisture limitation. Various microclimatic (light availability, wind speed and soil moisture) and soybean performance variables (leaf traits, 100-grain weight and yield) were measured at four distances from the tree row (4, 12 and 20 m, and control). RESULTS AND CONCLUSIONSRainfall exclusion decreased soil moisture and had a negative effect on soybean yield (−14%). The effect of the rain exclusion treatment on soybean performance was similar across all tree row distances and in both root-pruning treatments, which is contrary to our prediction. In 2018, an abnormally dry and warm season, yield near the alley centres was higher than near the tree row and tended to outperform the control. In 2019, a season with normal rainfall and temperature, soybean yield within the alleys was consistent among the different measured distances and did not differ from that in the control. Moderate shading at 4 m (−26% of PAR) was not associated with a change in soybean yield or leaf traits compared to other distances where shading was negligible or absent. Root pruning negatively affected soybean yield in 2018 (−14%) and 2019 (−22%), which is contrary to our prediction. SIGNIFICANCEThis case study adds to our knowledge regarding interactions between crops and trees in widely spaced TBI systems. TBI effects on spatial patterns of crop yield may vary substantially depending upon inter-annual variation in climatic conditions. This study suggests that more facilitative effects would prevail in dryer and warmer years, in contrast to near neutral effects in normal years.

Analysis of aerosol spreading in a German Inter City Express (ICE) train carriage

This paper focuses on the propagation of aerosols in a rolling stock passenger compartment. Extensive measurements were carried out in our stationary test vehicle DIRK, an ICE 2 rail car, operated in a climate chamber.It is shown that the propagation of aerosols only occurs for a distance of a few seat rows. Furthermore, the maximum percentage of particles exhaled by a passenger and inhaled by another passenger is less than 0.35%. A mouth-nose-protection (surgical mask) at the aerosol source reduces this value to a maximum of 0.25%. Moreover, the use of a mouth-nose-cover reduced the propagation lengths. Here, only the effect of the mask at the source was considered, a further reduction of inhaled aerosols will be achieved when the receivers also wear masks.It is concluded that, for this type of passenger coach, the indirect propagation of aerosols, i.e., via the HVAC system, is nearly irrelevant compared to the direct propagation from one passenger to another. However, there is a non-zero aerosol transport via the HVAC system, resulting in local inhaled particles far away from the source of around 0.015–0.026%, which is more than one order of magnitude lower than on the most highly contaminated seats.

Kahramanmaraş Koşullarında Çörek Otu (Nigella Sp.) Genotiplerinde Farklı Sıra Arası Mesafelerin Verim ve Kaliteye Etkilerinin Belirlenmesi

Bu çalışmada, farklı sıra arası mesafelerinin N. sativa L., N. damascena L., ve tescilli çeşit olan Çameli (N. sativa) genotipleri üzerinde tarımsal ve kalite özelliklerinin belirlenmesi amaçlanmıştır. Çalışma 2019-2020 vejetasyon dönemlerinde Kahramanmaraş Sütçü İmam Üniversitesi Ziraat Fakültesi Tarla Bitkileri Bölümü Araştırma ve Uygulama arazisinde sıra arası mesafeleri 20, 30, 40 ve 50 cm olacak şekilde yürütülmüştür. Deneme, tesadüf bloklarında bölünmüş parseller deneme desenine göre 3 tekerrürlü olarak kurulmuştur. Farklı sıra aralıklarında ekilerek yetiştirilen çörek otu genotiplerin de; bitki boyu 30.25-56.90 cm, ilk dal yüksekliği 1.58-15.62 cm, ilk kapsül yüksekliği 11.52-30.70 cm, dal sayısı 5.40-7.10 adet bitki-1, kapsül sayısı 8.37-28.37 adet bitki-1, kapsüldeki tane sayısı 7.00-26.33 adet kapsül-1, bin tane ağırlığı 2.18-2.71 g, tohum verimi 51.39-155.00 kg da-1, sabit yağ oranı %28.65-36.40, protein oranı %19.28-22.32, uçucu yağ oranı %0.58-1.12, sabit yağ verimi 20.36-53.35 kg da-1ve uçucu yağ verimi 0.34-1.74 L da-1 olarak bulunmuştur. Yürütülen bu çalışmada; genotip olarak Çameli çeşidinden (N. sativa) ve sıra arası mesafede ise; istatistiki olarak aynı grupta yer alan 30 (155.00 kg da-1 tohum verim) cm ve 20 (151.39 kg da-1 tohum verim) cm sıra arası mesafelerinden en yüksek tohum verimi elde edilmiştir.

English

The objective of this work was to evaluate the agronomic characteristics of maize intercropping with Eucalyptus urophylla at agroforestry system in two triple row distance (alleys) at different sampling distances and positions in relation to the eucalyptus external row (transect), and three positions in relation to the cardinal points: east side, west side and middle. Eucalyptus (E. urophylla) seedlings were planted with spacing of 1.5 m between plants and 3.0 m between rows (triple rows) and two triple row distances: 16.5 and 37.1 m apart, with the spatial exposure of the rows towards north and south, ranging from 888 to 464 plants ha-1. It was observed that treatments differed in relation to the number of ears ha-1 and grain yield in both seasons. In addition, in relation to the final plant density ha-1, in the 2014/2015 season, the maize at 4.2 m distance from eucalyptus at 16.5 m triple row distance had lower number of ears ha-1 and grain yield, and maize at 8.2 m from eucalyptus at 37.1 m triple row distance had greater number of ears and grain yield. The cardinal positions (W/E) in relation to the eucalyptus did not influence the agronomic characteristics of the maize. Key words: Cropping systems, integrated systems, Zea mays.

Calculation model of shotcrete support thickness based on elastic thin plate theory

In order to accurately calculate the thickness of shotcrete in tunnel, the support load, inter-anchor row distance and concrete mechanical properties are selected as influencing factors, and a mechanical model of shotcrete support thickness is established based on the elastic thin plate theory to derive the relationship between support load, inter-anchor row distance, concrete mechanical properties and concrete thickness. The controlled variable method (CVM) was used to study the variation law of support load and inter-anchor row distance with concrete thickness. The results show that: the mechanical properties of the concrete slurry remain unchanged, the required thickness of the concrete support increases with the increase of the support load, in a power of 1/2 relationship, with the increasing thickness of the shotcrete, the concrete is prone to shear damage to tensile damage until the thickness meets the engineering requirements; the support load remains unchanged, the thickness of the concrete support is linearly related to the anchor rod spacing, with the increase of the anchor rod spacing As the anchor spacing increases, the required thickness of concrete support also increases linearly. This paper successfully defines the relationship between the required concrete support thickness, support load and anchor rod parameters for shear and tensile damage, and through the analysis of the anchor spraying case, it is believed that the calculation model is reasonable and the results can provide a theoretical basis for the quantitative design of the support system.

Rapid prediction of the ultimate moment of flush endplate connections at elevated temperatures through an artificial neural network

Steel connections are vulnerable structural components, and their failure can lead to the collapse of the whole structure in a fire. Hence, it is crucial to predict the connection behaviors accurately to enable a precise prediction of structural performance in the fire. This paper proposes an efficient approach for predicting the ultimate moment of flush endplate connections at elevated temperatures using the finite element method and an Artificial Neural Network (ANN). Firstly, a finite element model considering both geometric and material nonlinearities is developed and verified with existing experimental results conducted by others. Based on the validated finite element model, an ABAQUS plug-in, namely COinFIRE, is implemented in ABAQUS to facilitate the parametric study. Consequently, 886 finite models are generated and used as training data for developing the ANN model. Accordingly, the endplate thickness, the pitch of bolts, the bolt row distance, the outer edge distance, the gage distance, the bolt diameter, the number of bolt rows, and the material properties at elevated temperatures are considered input variables. Meanwhile, the output is the ultimate moment. The obtained results show that the proposed ANN model can accurately predict the ultimate moment of flush endplate connections (R2 = 1.0, 1.0, 1.0, RMSE = 0.811 kN.m, 1.627 kN.m, 1.256 kN.m, and a20-index = 1.0, 1.0, 1.0 for the training, testing and validation datasets, respectively). Finally, closed-form formulas and a graphical user interface (GUI) tool are developed to evaluate the ultimate moment of flush endplate connections at elevated temperatures for practical use. The proposed approach shows great promise as a powerful design tool for steel connections at elevated temperatures.

Subsurface banding poultry litter influences edamame yield, forage quality, and leaf greenness

AbstractPoultry litter is generated in large quantities throughout the southeastern United States and is an excellent nutrient source for increasing crop yields. However, surface applications result in nutrient losses to air, soil, and water. Subsurface banding poultry litter is a promising technology for reducing nutrient losses to surface and groundwater, but information is needed on optimum crop seeding distance from bands. This study evaluated edamame [Glycine max (L.) Merr. ‘Edamame’] yield (residue, pod, and total plant), crop quality, and leaf greenness. Subsurface banded poultry litter and crop row distances (13, 25, and 38 cm) were compared with surface‐applied poultry litter (all received 168 kg ha−1 total N) under irrigated and nonirrigated conditions from 2019 to 2020. Both chlorophyll and edamame total yields were greatest (P ≤ .05) under subsurface banding litter, relative to surface applications, regardless of distance. Overall, greatest total crop yields were observed for 13‐ and 25‐cm banding distances under irrigation and the 38‐cm distance, irrespective of irrigation, relative to surface applications. Residue nutritive value for the 13‐cm distance was greater under irrigation than dryland. Both systems provided high levels of nutritive residual mass, thus edamame could be used as a vegetable crop and a forage following harvest. Overall, subsurface banding poultry litter in conservation tillage systems is a viable replacement to surface applications for edamame production (vegetable and fodder), particularly in organic systems. Results can be used to develop nutrient management plans for organic edamame and other specialty crop production systems in the Mid‐South.

Barrier effect against Bemisia tabaci and the control of tomato yellow leaf curl virus in a tomato-maize intercropping system

We examined the barrier effects against Bemisia tabaci and the potential to control the tomato yellow leaf curl virus (TYLCV) of different tomato-maize intercropping modes. Tomatoes (variety Jinshan 511) were planted at a fixed row distance either as a monoculture or together with maize (variety Xianyu 335) at the distances of 10, 20, and 30 cm. We investigated the viral index for TYLCV and the population density of B. tabaci. Compared with tomato monoculture, the natural barrier established by the maize stabilized the growth environment for tomato. When the maize spacing was 10, 20, and 30 cm, the average temperature of tomato plants from 6:00 to 20:00 decreased by 3.01, 2.26, and 1.45 ℃, the average relative humidity increased by 13.0%, 8.8%, and 6.0%, and the mean light intensity reduced by 26.1%, 20.4%, and 14.5%, respectively. The changes of those factors alleviated the adverse environmental conditions (i.e., intense light, high temperature, and lack of moisture) that promote the spread of virus-related diseases during the high-temperature period of the day, with the most effective planting distance for the maize being 10 cm. Our results suggested that the intercropping of tomato and maize had a barrier effect against B. tabaci and was able to control the TYLCV in tomato. When the planting distance for the maize was 10, 20, and 30 cm, the number of B. tabaci was 88.7%, 82.0%, and 73.9% lower than tomato monoculture, respectively. The TYLCV was inhibited, with the viral disease index being decreased by 67.3%, 59.4%, and 44.5%, respectively. Tomato-maize intercropping was also beneficial for tomato plant growth and fruit set, which could enhance tomato yield. Such effect was strengthened under higher maize density.