Row Length Research Articles

Performance Of Marvel Grass Varieties Under Different Levels Of Nitrogen In Irrigated Condition Of The Middle Gujarat Agroclimatic Zone Of Gujarat

Main Forage Research Station, ICAR Unit 9, Anand Agricultural University located in the middle agroclimatic zone of Gujarat India, has different Agroclimatic zone with a different agricultural pattern. Most of the farmers are doing agriculture as a first enterprise and dairy as a second one. The demand for fodder is higher in the different zone of Gujarat state. To improve cultural practices and reduced the shortfall of fodder with highly nutritive fodder these studies were carried out to evaluate the effect of the level of nitrogen on different marvel grass varieties in middle Gujarat. Continuous three years of experimentation on marvel grass, results revealed that marvel grass varieties did not show significant effects on growth, yield attributes, and yield as well as quality parameters. A perusal of experiment data revealed that application of 60 kg N/ha (30 kg N/ha at the time of transplanting or immediately after cutting and 30 kg N/ha at 30 DAS/ 30 Days after each cutting) noted higher growth parameters (height and several tillers per meter row length) also reported higher total green fodder yield and quality of marvel grass as well as higher net return and benefit-cost ratio.

Optimizing Carrot Harvesting Machine Design: Incorporating Soil and Crop Parameters

Mechanization in carrot harvesting is essential to save time and reduce labour-intensive work as well as harvesting costs. The aim of the study was to determine the soil properties and plant parameters for designing an appropriate carrot (cv: Madhuvan) harvesting machine, that would address the challenges faced by farmers. The physical characteristics of the soil and carrot plants significantly influence the design of the digging, conveying, de-topping, and collection units. These parameters include the digging depth, blade angle, forward speed, plant catch height, conveyor belt spacing, conveyor speed, and collection unit size. The mean values of shoot length, root length and shoot diameter at top of carrot were 62.5 cm, 26.5 cm, and 3.72 cm, respectively. The average weight of carrot root was 61.85 g. The mean values for spacing between ridges, height of ridge and width of ridge were 44.3 cm, 12.1 cm, and 42.8 cm, respectively. The mean number of carrots per meter row length was observed as 41. The black cotton soil with a mean moisture content of 19.77% (d.b.) at the harvesting stage of carrot, and its bulk density measured 1.31 g cm-3, while the average value of soil resistance was 2153.5 kPa. By utilizing this data, the machine's design can be fine-tuned to ensure effective digging performance while minimizing any potential damage to the carrot roots during the harvesting.

Identification of species of the genus Sylvaemus of northeastern Ukraine by metric characters

The reliable identification of representatives of the genus Sylvaemus is compli-cated by the huge coincidence of external and metrical characters, as well as by the fact that in most of their range, mice are in conditions of sympatry or even syntopy Moreover, identification is complicated by opposite clinal variability in size and geographic variability in fur colouration. The species are also similar in karyotypes, so their reliable identification is usually possible only based on biochemical or molecular analysis. The craniological collection of small mam-mals of O. V. Zorya and collection specimens of the Museum of Nature of V. N. Karazin Kharkiv National University were studied. In total, 436 speci-mens of three species of the genus Sylvaemus were analysed: Sylvaemus ura-lensis, Sylvaemus sylvaticus, and Sylvaemus tauricus. Analysed were 14 odon-tometric and 23 craniological characters. Among the metric characters, three odontometrical—width of first upper molar (WM1), length of second lower molar (LM2), length of lower molar row (LM123)—and seven craniometrical characters—length of first upper molar (LM1), length of foramen incisivum (LFI), length of upper molar row (LUM), width of choana (WCH), height of skull including bulla tympanica (HBCB), length of lower molar row (LLM), length of mandible (LM)—made the greatest contribution to the differentiation of mice of the genus Sylvaemus. Width of first upper molar (WM1), length of first lower molar (LM1), length of second lower molar (LM2), length of brain-case (LBC), least interorbital constriction (LIOC), width of braincase (WBC), distance between incisor and M3 (LIM3), length of upper molar row (LUM), condylobasal length of skull (CBL), palatal length (LPP), greatest length of skull (GLS), and length of lower molar row (LLM) are the least variable metric char-acters. Scatterplots linking LLM/CBL, LUM/CBL, and LUM/GLS appeared to be the most suitable for differentiating the specimens, with minimal overlap of species in the morphospace. In north-eastern Ukraine, the best distribution of mice of the genus Sylvaemus was obtained as a result of the analysis based on both odontometrical and craniological characters, when the correctness of the classification was 100%.

Spike performance transgression degree and frequency in F2 winter bread wheat hybrids

Purpose and Objectives. To analyze the spike performance transgression degree and frequency in F2 winter bread wheat hybrids.
 Materials and Methods. The study was carried out in the Laboratory of Genetic Resources of Cereals of the Plant Production Institute named after V.Ya. Yuriev of NAAS in 2019–2021. Thirty 30 F2 hybrids from diallel crossings and 20 F2 hybrids from tester crossings were investigated. The experiments were carried out in accordance with the requirements for field experiments in breeding. F2 hybrids and their parents were sown with a manual single-row planter within the optimal timeframe. The row length was 1 m; the interrow distance was 20 cm; the depth was 4–6 cm; wheat was sown after bare fallow. Twenty seeds per row were sown. Data were statistically processed, as B.A. Dospekhov recommended. The transgression degrees and frequencies for quantitative traits were determined by the formulae proposed by H.S. Voskresenskaya and V.I. Shpota.
 Results and Discussion. Analyzing the F2 hybrids from diallel crossings, positive transgressions of the “pike length” trait were found in all the analyzed hybrids. The highest degree of transgressions was recorded for Ladyzhynka / Dyvo (Td = 18.0%) and Vodohrai Bilotserkivskyi / Ladyzhynka (Td = 12.1%); the highest frequency of transgressions of this trait was observed in Ladyzhynka / Dyvo (Tf = 89.7%) and Khvala / Dyvo (Tf = 85.0%). The maximum degree of transgressions for the kernel number per spike was detected in Vodohrai Bilotserkivskyi / Khvala (Td = 12.9%), and the maximum frequency of transgressions of this trait was noted in Kubok / Ladyzhynka (Tf = 50.7%). Kubok / Dyvo was selected due to degree and frequency of spike weight transgressions (Td = 25.7%; Tf = 54.3%). The maximum advantage over the better parent in terms of the spikelet number per spike and the maximum frequency of transgressions of this trait were noted in Vodohrai Bilotserkivskyi / Khvala (Td = 18.6%; Tf = 88.7%). The maximum advantage over the better parent in terms of kernel weight per spike was detected in Kubok / Dyvo (Td = 27.7%); but the highest frequency of transgressions of this trait was recorded for Kubok / Korovaina (Tf = 54.3%). As to thousand kernel transgression degree and frequency, Kubok / Dyvo was distinguished (Td = 12.4%; Tf = 82.7%).
 Analyzing the F2 hybrids from tester crossings, the Khvala / Kanada (Td = 10.7%) and Dyvo / Arktis (Td = 10.6%) hybrids were distinguished by spike length transgression degree; Khvala / Kanada was noticeable for transgression frequency for this trait (Tf = 79.7%). As to the spikelet number per spike, the highest degree of transgressions were observed in Khvala / Viglanka (Td = 16.4%) and the highest frequency of transgressions - in Khvala / Viglanka (Tf = 51.3%) and Vodohrai Bilotserkivskyi / Arktis (Tf = 51.3%). The maximum advantage over the better parent in terms of the kernel number per spike was detected in Ladyzhynka / Arktis (Td = 13.6%); this combination was also noticeable for the maximum frequency of transgressions of this trait (Tf = 47.0%). By spike weight transgression degree, Ladyzhinka / Arktis was distinguished (Td = 26.2%); by transgression frequency for this trait – Vodohrai Bilotserkivskyi / Kanada (Tf = 60.7 %). The maximum degree of transgressions of kernel weight per spike was observed in Ladyzhynka / Arktis (Td = 29.7%) and the maximum frequency of transgressions of this trait - in Dyvo / Viglanka (Tf = 55.0%). By thousand kernel weight transgression degree, Dyvo / Donera (Td = 11.9%) and Vodohrai Bilotserkivskyi / Viglanka (Td = 11.2%) were selected and by transgression frequency for this trait - Vodohrai Bilotserkivskyi / Viglanka (Tf = 92.0%).
 Conclusions. The degree of positive transgressions of spike length among F2 hybrids from diallel crossings averaged 6.9% and the frequency – 52.6%; for the spikelet number per spike the corresponding parameters were 7.8% and 44.8%; for the kernel number per spike – 5.4% and 21.4%; for spike weight – 6.3% and 23.4%; for kernel weight per spike – 6.9% and 22.5%; and for thousand kernel weight – 0.1% and 31.2%. The degree of positive transgressions of spike length among F2 hybrids from tester crossings averaged 4.6% and the frequency – 36.5%; for the spikelet number per spike the corresponding parameters were 6.9% and 30.5%; for the kernel number per spike – 5.4% and 26.0%; for spike weight – 10.1% and 30.2%; for kernel weight per spike – 11.8% and 30.3%; and for thousand kernel weight – 2.4% and 34.0%.

Row-spacing and cultivar effects on sugarcane growth and yields in Florida histosols

Sugarcane (Saccharum spp. hybrids) is a major row crop in Florida. The effect of row-spacing on total row length per hectare can significantly effect the cost of major farm operations, including planting, harvesting and fertilizer application. In Florida, sugarcane is commonly planted at 1.5 m row-spacing. There is little information available on the effect of relatively narrow or wide spacing on the growth and yield of sugarcane, especially in new high-biomass cultivars. To determine sugarcane growth response to different row-spacing, a field trial was conducted in organic soil (Histosols) with four different row-spacings (1.2, 1.5, 1.8 m and a double row on a 1.5 m bed) and three sugarcane cultivars (CP 96-1252, CP 00-1101 and CP 01-1372). Data showed differential row-spacing effects on plant cane versus the first ratoon. In plant cane, depending on the cultivar, double row and 1.2 m spacing produced 17–46% and 23–42% greater sugar yield per hectare (TSH) than the current 1.5 m spacing, respectively. Overall, the combined average TSH of plant cane and the first ratoon in double and 1.2 m spacing was 20% and 26% greater than 1.5 m spacing. However, the yields in 1.5 m and 1.8 m row-spacing were similar. There was no significant effect in the first ratoon. There was no row-spacing effect on sucrose concentration. A similar response of cultivars to the tested row-spacings suggests that selecting cultivars for different row-spacings may not potentially show any yield improvements. Compared to the current 1.5 m spacing, narrow-spacing (1.2 m and double row) may potentially increase yields and wide (1.8 m) spacing reduce the production cost but further research is needed to understand the economic feasibility of different row configurations.

A STUDY OF THE EFFECT OF INTEGRATED NUTRIENT MANAGEMENT ON YIELD ATTRIBUTES AND YIELDS OF WHEAT AND ITS RESIDUAL EFFECT ON SUCCEEDING GREEN GRAM

The sandy loam soil and gentle slope of the test plot allowed for adequate water drainage. The top fifteen centimetres of the soil in the experimental field had a slightly alkaline response, was low in organic carbon and accessible nitrogen, and was medium in available phosphorus and potassium. In both 2018 and 2019, integrated nutrition management treatments had no detectable influence on plant population (per metre of row length) at either 30 DAS or harvest. There was no significant difference in plant height at 30 DAS between the integrated nutrition management treatments in either 2018–19 or 2019–20, or in the pooled result.

Effects of Integrated Use of Organic Manure and Bio-fertilisers on Crop Productivity: A Case Study of Rice (Oryza sativa L.) Crop

The present study conducted entitled, “Effect of Integrated use Organic manure and Bio-fertilizers on crop productivity under Rice (Oryza sativa L.) crop". Involved field trial conducted during Kharif season of year 2016-17 followed by laboratory analysis of the plant and soil samples in the Department of Soil science & Agriculture Chemistry, Udai Pratap Autonomous College, Varanasi (U. P). All grasses were removed from the experimental plots and soil samples have been taken from each replication plots at 30 DAT, 60 DAT and at harvesting. The experiment was conducted under randomized block design (RBD) with six treatment combinations. Treatments were replicated thrice making the total number of 18 plots. The effect of various treatments on dry matter production could be arranged in order of T6>T3>T5>T4>T2>T1 and the values were 70.25, 62.15, 59.45, 43.40, 41.25 and 35.59 gm-1 row length, respectively. Application of fertilizers alone or in combination with F.Y.M increased grain and straw yield of rice significantly over control. Further, the yield was significantly superior under the use of organic manure and bio-fertilizers over the sole use of chemical fertilizers. On the basis of data, the superiority of the treatments may be arranged as T6>T3>T5>T4>T2 and T1. Like dry matter yield, rice grain and straw yield was also highest in treatment where 50% NPK was substituted through FYM to rice crop. The integrated use of fertilizers with FYM and bio-fertilizers might have added huge quantity of organic matter in soil that increased grain and straw yield. In general, higher number of tillers (15.25 m-1 row length), plant height (92.50 cm), dry matter at 60 DAT (70.25 gm-1 row length), grain yield (46.25 Qha-1 ) and straw yield (91.25 Qha-1 ) obtained with T6 treatment followed by T3>T5>T4>T2>T1 (control).

Conservation and organic management practices influenced wheat (Triticum aestivum) productivity, profitability and weed dynamics

Present study was carried out during winter (rabi) seasons of 2018–19 and 2019–20 at the Agricultural Research Station of Agriculture University, Kota, Rajasthan to assess the effects of conventional and conservation tillage with organic and chemical management on growth, yield attributes, yields, economics and weed dynamics in wheat (Triticum aestivum L.) in Vertisols. Five different crop-management practices, viz. conservation tillage with organic management (CAO), conservation tillage with chemical management (CAC), conventional tillage with chemical management (CTC), conventional tillage with organic management (OCT) and package of practice (PoPs) were studied in a randomized block design (RBD) with 4 replications. Pooled data revealed that significantly higher plant height (97.7 cm), dry matter accumulation (169.24 g/0.5 metre row length), number of tillers (47.05/0.5 meter row length), chlorophyll content of leaves (2.186 mg/g), number of effective tillers (43.15/0.5 meter row length), spike length (12.86 cm), weight per spike (2.49 g), test weight (45.61 g), grain yield (5214 kg/ha), straw yield (7941 kg/ha), and net returns (` 90891/ha) were recorded under CAC practice over CAO and OCT, although it was observed to be comparable to the PoPs and CTC management practices. Comparing conservation tillage with chemical management to other crop management techniques at 60 DAS, it was found to be the most successful practice for controlling total weeds (9.40/m2) and decreasing the buildup of weed dry matter (167.21 kg/ha).

Influence of deep-cement-mixing column rows on the performance of geosynthetics-reinforced column-supported railway embankment

Knowledge regarding the stability of geosynthetics-reinforced column-supported railway embankment (GRCSE) on soft foundation is of great significance for transportation infrastructure safety design, and deep-cement-mixing (DCM) columns constructed under the toe of an embankment is used to improve the performance of GRCSEs. This study conducted two centrifuge model tests to simulate the failure of a constructed embankment in a 40-g environment. The failure mechanism of each component in the GRCSE system and the effect of additional DCM column rows near the embankment toe on the GRCSE performance were analysed. The particle image velocimetry (PIV) technique was used to draw further insights from the results. The tests revealed that a failed column within the GRCSE system led to the progressive failure of adjacent columns, coupled with the progressive and retrogressive propagation of shear strains in the soft soil, which resulted in embankment collapse. The addition of DCM column rows near the embankment toe reduced the local shear strain accumulation in the soft foundation and thus improved the overall stability. The incremental tensile strain of the geosynthetic reinforcement in various phases was different in the cases with and without additional DCM column rows. Moreover, the effects of various factors of DCM rows, including row number and length, on the GRCSE stability were numerically analysed.

A novel method for dense point cloud reconstruction and weld seam detection for tubesheet welding robot

Welding is not yet fully automated, which is mainly limited by the manual drawing of the welding model. A novel method of automatically establishing a dense point cloud model of the tubesheet and detecting the weld seam was proposed to solve the issue in this paper. The multi-sensor system was calibrated with a fast calibration method, and a laser filter algorithm was then applied to fuse the multi-sensor data. The vocabulary tree method was carried out for tubesheet image similarity analysis, followed by the Random Sample Consensus (RANSAC) algorithm used for feature matching, aiming to establish a point cloud model based on epipolar constraint, EPNP and PMVS algorithm. Finally, a weld seam detection algorithm based on voxel point cloud density was proposed to detect the weld seam in the point cloud. After comparison, the reconstruction method has better robustness than the reference. The point cloud measurement results showed that the average row and column length errors of the reconstructed point cloud were both less than 1 %, which can meet the requirements in current welding applications. And the proposed weld seam detection method can reduce the detection error rate from 20.83 % to 9.03 %.

Optimizing Cow Urine Application Rate at Varying Fertility and Zinc Levels on Wheat (Triticum aestivum L.) Productivity under Dairy Based Farming System in Varanasi Tract

This field investigation was carried out in two consecutive years of 2016-17 and 2017-18 at the Agricultural Research Farm, Banaras Hindu University, Varanasi (U.P.) to assess the effect of cow urine application at varying fertility and zinc levels on growth and yield of wheat (Triticum aestivum L.) under irrigated condition of Varanasi. Results showed that application of the fertilizer at 100% recommended dose of fertilizers (RDF) recorded significantly higher growth parameters viz. plant height, number of tiller m-1 row length; yield attributes viz. number of effective tiller m-2, spike length, grains spike-1 and test weight as well as grain and straw yield than 75% RDF during both the years. Among the zinc levels, zinc applied at 10 kg ha-1 though remained comparable to 5 kg Zn ha-1, recorded significantly higher values of these parameters over control. Cow urine at the rate of 12000 l ha-1 applied equally at sowing, CRI (Crown Root Initiation) and spike emergence (SE) stages gave higher values of plant height, number of tiller m-1 row length, spike length and number of grain spike-1 which being at par with 4000 l ha-1 cow urine each at sowing and CRI, both recorded significantly higher values than control. However, with respect to effective tillers m-2, grain and straw yield, significant increase was noticed with each increment of cow urine, recording maximum at 12000 l ha-1 during both the years.

Inheritance of spike productivity elements in F1 winter bread wheat hybrids

Inheritance of spike productivity elements in F1 winter bread wheat hybrids

Effects of different mulching materials on yield and yield components of maize (Zea mays L.)

Two field experiments were conducted during dry season (October, 2019 to March, 2020) at Yezin Agricultural University farm and Sepin research farm, Yamethin, Myanmar to investigate the effect of different mulching materials on yield and yield components of maize. No mulching and six mulching materials (rice straw mulching, rice husk mulching, maize stover mulching, mung bean stover mulching, soybean stover mulching and white plastic polyethylene mulching) were laid in a Randomized Complete Block Design (RCB) with three replications on NK-621 variety. The longest days to 50% tasseling (69.67) at Yezin and (71.67) at Yamethin were obtained in no mulching while the shortest days to 50% tasseling (62.00) at Yezin and (64.33) at Yamethin were observed from rice straw mulching at Yezin and white plastic polyethylene mulching at Yamethin. Number of kernel row-1, rows ear-1, row length, kernels ear-1, thousand grains weight were significantly different among different mulching materials at Yezin. The maximum grain yield (5.72 ton ha-1) and (10.39 ton ha-1) were observed from rice straw mulching at Yezin and Yamethin. According to the results, rice straw mulching resulted in the highest yield and yield components of maize at two locations.

Use of different selection indices for improving the genetic gain in maize (Zea mays L.)

Plant breeding relies heavily on artificial selection for improving grain yield through various yield contributing traits. The selection of complex quantitative traits like maize grain yield is difficult due to less heritability and a greater influence of the environment. The present study was made using 25 maize inbred lines aimed at identifying yield-attributing traits and identifying simultaneous selection models based on discriminant functions. The expected genetic gain for grain yield when all the studied traits were included in simultaneous selection was higher (51.86) than that of selecting grain yield alone (33.96). There were four traits that made up the ideal discriminant function: grain yield, kernels per row, 100-grain weight and cob length which had 49.57 percent relative efficiency and 155.29 percent genetic advance. The relative efficiency of selection considering grain yield alone was at 106.38%, but when five (X1, X2, X3, X5, and X6) and six traits were simultaneously considered the efficiency increased to 160.37 and 162.47%. Based on the ideal discriminant function among the genotypes G17 was selected as the best inbred line with the highest selection score of 66.57 followed by G20 (65.19) and G22 (65.01). Whereas, G23 was the last with 17.05 selection score

Heterosis and Combining Ability Studies in A 5x5 Diallel Crosses of Maize Inbred Lines

The present study was conducted to evaluate the genetic architecture of five diverse maize genotypes using combining ability analyses. General combining ability (GCA) mean squares were non-significant for grain yield and its related components. Specific combining ability (SCA) mean squares were highly significant for grain yield, the number of grains per row and cob girth while non-significant for days to tasseling, days to silking, plant height, cob height and cob length. These studies suggested the preponderance of non-additive type of gene action for grain yield, cob girth and number of grains per row and additive gene action for days to tasseling, days to silking, plant height, cob height and cob length. The genotypes MIL2020-51 and MIL2020-52 were good general combiners for grain yield, grains per row, cob height and plant height. These lines were the poorest general combiner for days to 50% tasseling and days to 50% silking which suggested that these genotypes had sufficient genes for inducing earliness. The crosses MIL2020-51 x MIL2020-54, MIL2020-52 x MIL2020-53, MIL2020-51 x MIL2020-55, MIL2020-53 x MIL2020-55and MIL2020-52 x MIL2020-55 were the best performing combinations for grain yield. These crosses involved good x good and good x poor general combiners. The reciprocal cross combinations MIL2020-55 x MIL2020-53, MIL2020-52 x MIL20220-51, MIL2020-54I x MIL2020-52, MIL2020-55 x MIL2020-51, MIL2020-54 x MIL2020-51and MIL2020-55 x MIL2020-54 showed large positive estimates for grain yield suggesting that cytoplasmic inheritance also had a role in the expression of grain yield. SCA variances were higher than GCA variances for grain yield, plant height, cob height, number of grains per row, cob girth and cob length which highlighted major role of non-additive genes in the inheritance of these traits. Additive gene action was found more important for number of days to 50% tasseling and number of days to 50% silking

Role of Oxalic Acid in Expression of Resistance against the Pod Borer Helicoverpa armigera (Lepidoptera: Noctuidae) in Chickpea Varieties

Background: Pod borer is most serious problem to cultivation of chickpea across the world. In India, Madhya Pradesh rank first in both area and production of chickpea. This region is considered most affected yield of chickpea due to H. armigera. Host plant resistance is an important component for managing this pest. To develop cultivars with resistance to insects, it is important to understand the role of oxalic acid associated with resistance to this pest. The current study aimed to study the role of oxalic acid in expression of resistance against the pod borer Helicoverpa armigera (Lepidoptera: Noctuidae) in chickpea varieties under climate change. Methods: This investigation was carried out at Research Farm of Soybean Seed Production-Unit, College of Agriculture, JNKVV (MP) during Rabi season 2019-20 and 2020-21. The field experiment was laid out in split split plot design with 24 treatments and three replications. The treatments included three date of sowing i.e. 15th November, 30th November and 15th December as a main plots, two irrigation levels i.e. I0-no irrigation and I1- irrigation at 35 DAS as a sub plots and four chickpea varieties i.e. JG 12, JG 36, JG 14 and JG 24 as sub sub plots. The observation on number of eggs and larval population of H. armigera were recorded from one-meter row length (mrl). At five randomly selected places were averaged separately for each plot and made in to number of eggs and larval population per meter row length (mrl). The amount of oxalic acid in chickpea leaves was determined by UFLC method. The correlation was worked out with population of pod borer and amount of oxalic acid in chickpea varieties. Result: In this investigation, the ultra-fast liquid chromatography (UFLC) profiles of the leaf exudates of chickpea varieties exhibited amounts of oxalic acid significantly negative correlation with egg count and larvae incidence of H. armigera.

New species Eutobrilus Gagarini sp. n. and a review of species of the genus Eutobrilus from graciliformis-group (Nematoda: Tobrilida, Tobrilidae, Eutobrilinae)

A new species of Eutobrilus gagarini sp. n. from the Leningrad region is described, which is included in the morphological graciliformis-group of the genus Eutobrilus and differs from other species of the group by a high coefficient "b" and a smaller ratio of the length of the spicules to the length of the supplementary row and the ratio of the length of the spicules to the length of the body. A key for determining the Holarctic species of the graciliformis-group is given and the composition and structure of this group as a whole are discussed. The expediency of isolating the morphological graciliformis-group is discussed. The synonymization of the genus Peritobrilus Gagarin, 1993 with the genus Eutobrilus Tsalolikhin, 1981 is confirmed.

The tetrapod fauna of the upper Permian Naobaogou Formation of China: 9. A new species of Gansurhinus (Reptilia: Captorhinidae) and a revision of Chinese captorhinids

ABSTRACT Two previously studied specimens of Gansurhinus qingtoushanensis are restudied, accompanied by the description of a relatively complete skeleton from the Lopingian Naobaogou Formation of Nei Mongol, China. The new skeleton represents an immature individual of a new species of Gansurhinus, which can be diagnosed by the choana position posterior to the premaxillary teeth, maxillary tooth position numbers of tooth row 5 is about half of tooth row 4, and length of row 5 is much shorter than length of tooth row 4. IVPP V12026 from the Naobaogou Formation is referred to the new species. Gansurhinus is distinguished by a diastema on the upper jaw, five rows of teeth on maxilla and dentary, teeth on the multiple tooth-rowed region bearing cusp-like emargination on the crown, lacking dental tooth wear. The following features could be the diagnostic characters of the genus or autapomorphies of the new species: ectopterygoid present; adductor fossa short relative to the length of lower jaw, with small contribution of surangular to posterolateral border; trapezoidal coronoid eminence with nearly straight dorsal margin; and foramen intermandibularis caudalis absent. Gansurhinus is more closely related to Rothianiscus than Moradisaurus, supporting previous analyses. This study further confirms recent work suggesting that the moradisaurine clade is more diverse than currently recognized.

The Burge correspondence and crystal graphs

The Burge correspondence yields a bijection between simple labelled graphs and semistandard Young tableaux of threshold shape. We characterize the simple graphs of hook shape by peak and valley conditions on Burge arrays. This is the first step towards an analogue of Schensted’s result for the RSK insertion which states that the length of the longest increasing subword of a word is the length of the largest row of the tableau under the RSK correspondence. Furthermore, we give a crystal structure on simple graphs of hook shape. The extremal vectors in this crystal are precisely the simple graphs whose degree sequence are threshold and hook-shaped.

Genome-wide association studies revealed complex genetic architecture and breeding perspective of maize ear traits

BackgroundMaize (Zea Mays) is one of the world’s most important crops. Hybrid maize lines resulted a major improvement in corn production in the previous and current centuries. Understanding the genetic mechanisms of the corn production associated traits greatly facilitate the development of superior hybrid varieties.ResultIn this study, four ear traits associated with corn production of Nested Association Mapping (NAM) population were analyzed using a full genetic model, and further, optimal genotype combinations and total genetic effects of current best lines, superior lines, and superior hybrids were predicted for each of the traits at four different locations. The analysis identified 21–34 highly significant SNPs (−log10P > 5), with an estimated total heritability of 37.31–62.34%, while large contributions to variations was due to dominance, dominance-related epistasis, and environmental interaction effects ({h}_{D+}^2hat{=} 14.06% ~ 49.28%), indicating these factors contributed significantly to phenotypic variations of the ear traits. Environment-specific genetic effects were also discovered to be crucial for maize ear traits. There were four SNPs found for three ear traits: two for ear length and weight, and two for ear row number and length. Using the Enumeration method and the stepwise tuning technique, optimum multi-locus genotype combinations for superior lines were identified based on the information obtained from GWAS.ConclusionsPredictions of genetic breeding values showed that different genotype combinations in different geographical regions may be better, and hybrid-line variety breeding with homozygote and heterozygote genotype combinations may have a greater potential to improve ear traits.