Number Of Spikes Research Articles

Effects of spraying cycocel and delaying nitrogen application on lodging resistance and yield formation of winter wheat.

We conducted a 3-year (2017-2020) field experiment in the wheat base of Jinzhong Agricultural Hi-tech Industries Demonstration Zone, aiming to determine the measures of nitrogen topdressing and the regulatory effect of cycocel in spring to increase wheat yield. Four nitrogen topdressing dates were set up under the condition of cycocel spraying and control (CK) during the rising period: 10 days (D10), 20 days (D20), 30 days (D30), and 40 days (D40) after regreening stage, to analyze the impact of different N topdressing dates on winter wheat yield and the regulation effect of cycocel on stem characteristics, lignin content and related synthetase activities. The results showed that compared to other nitrogen topdressing dates, D30 increased spike number by 1.4%-5.2%, grain number per spike by 0.4%-12.0%, 1000-grain weight by 1.7%-9.4% and yield 8.8%-22.1% respectively. Compared to D10 and D20, D30 significantly improved the activities of phenylalanine ammonia-lyase (PAL) at 0-21 days and 35-42 days after the formation of the second section and increased that of tyrosine ammonia-lyase (TAL) at 0-42 days after the formation of the second section, and increased the lignin content of stem, the internode quality, and the breaking resistance of stem, reduced plant height, and thereby improved the lodging resistance. However, D40 increased grain number per spike by 4.5%-10.1% and yield 0.04%-11.3%, but reduced the activities of PAL and TAL at 0-42 days after the formation of the second internode, reduced the lignin content, weakened the stem strength, and increased the risk of lodging. After spraying cycocel, plant height decreased significantly, the activities of PAL and TAL enhanced, the lignin content in internodes increased, the stem strength advanced, and reached a significant level under D30. Under the condition of nitrogen topdressing combined with cycocel spraying in spring, PAL and TAL activities were significantly positively correlated with lignin content. Lignin content was significantly positively correlated with stem breaking resistance. Stem breaking resistance was significantly positively correlated with lodging resistance index. Yield and its components were significantly posi-tively correlated with internode diameter, weight and breaking resistance, and significantly negatively correlated with plant height and internode length. Overall, nitrogen topdressing combined with spraying cycocel 30 days after regreening could promote the synthesis and accumulation of lignin, and improve stem plumpness, plant lodging resistance and yield.

Influence of crop management on stability rye yield and some grain quality traits

AbstractThe study explored the performance of hybrid and population rye (Secale cereale) cultivars under two different crop management intensities in Poland: moderate‐intensity and high‐intensity management. The focus was grain yield, grain quality, yield components, and variety stability in two growing seasons (2018/2019 and 2019/2020) at three locations. Hybrid cultivars consistently yielded higher grain yields (9.81 t ha−1) than population cultivars (7.90 t ha−1), with increase of 24.9%. However, hybrid cultivars had lower protein content (8.94%) than population cultivars (9.77%). Spike number was the most influential factor on yield, followed by 1000‐grain weight and grains per spike, regardless of cultivar type. Hybrid cultivars displayed a lower degree of stability as assessed using the ranking sum of the Shukla variance and the multi‐trait stability index. Hybrid cultivars were strongly dependent on resistance to fungal diseases, including Septoria (Mycosphaerella graminicola), and increased stability under moderate‐intensity management. Resistance to soil acidification became more important for cultivar stability under high‐intensity management.

Rice Growth and Leaf Physiology in Response to Four Levels of Continuous Drought Stress in Southern China

Exploring the growth and physiological response mechanisms of rice under continuous drought stress circumstances can provide a significant scientific foundation and technological assistance for meeting drought difficulties, improving drought resistance and rice (Oryza sativa L.) output, and ensuring food security. In this study, a rice field experiment was conducted under a rain shelter with five different treatments set up: P1 (drought stress from tillering stage), P2 (drought stress from jointing–booting stage), P3 (drought stress from heading–flowering stage), P4 (drought stress from grain filling stage), and CK (adequate water management throughout the growth stage). Continuous drought stress from different growth stages with four levels (mild, medium, moderate, and severe). The results showed that the effects of different drought stress treatments on rice growth varied significantly. Compared with the CK treatment, plant height was reduced by 12.10%, 8.14%, 3.83%, and 1.06% in the P1, P2, P3, and P4 treatments, respectively, and the number of tillers was reduced by 23.83%, 18.91%, 13.47%, and 8.68%, respectively. With the increase in drought stress levels, SPAD values and Rubisco activity of rice leaf continued to decrease; SOD activity showed a decreasing trend, but the decreasing trend of POD and CAT activities was not significant, while MDA content showed an increasing trend. For yield components, continuous drought stress significantly reduced spike length of rice by an average of 3.5%, effective number of spikes by 18.9%, thousand grain weight by 3.7%, grain number per spike by 11.6%, and fruiting rate by 1.8%, respectively, compared to CK treatments during the growth period. In general, continuous drought stress during the early growth period affected the effective spike number and the grain number per spike. Continuous drought stress after the grain filling stage had the least effect on yield (17.62% of yield reduction), and water use efficiency (1.76 kg m−3) was much higher than other treatments. These researchers’ findings provide insight into how rice physiology and growth react to continuous drought stress, which is significant for agricultural operations.

Winter wheat source‐sink relationships under various planting modes, complementary irrigation, and planting densities

AbstractVarious agronomic practices can affect the processes of aboveground dry matter accumulation (source) and grain filling (sink), resulting in yield differences. Improved source‐sink relationships can facilitate the production and accumulation of assimilates to increase the productivity of winter wheat (Triticum aestivum L.). A two‐season field experiment was undertaken on winter wheat during 2020–2021 and 2021–2022. In a split‐split‐plot design with three replicates (randomized blocks), we compared two planting modes (ridge‐furrow planting with plastic mulching [RFPM]; traditional flat planting [TF]), two complementary irrigation levels (I30+30: 30+30 mm; I0: no irrigation), and three planting densities (D1, D2, and D3: 240, 360, and 480 plants m−2). The results showed that RFPMI30+30 significantly increased maximum yield by 28.5% compared with TFI0. Although D3 increased the number of effective spikes per unit area and duration of grain filling compared to D2, it reduced the number of grains per spike, 1000‐grain weight, and average filling rate. Compared to TF and I0, RFPM and I30+30 improved the sink/source ratio by 5.3% and 6.5%, respectively. Grain yield peaked at D2 in the RFPM and at D3 in the TF. Medium planting density (D2) and complementary irrigation (I30+30) during the wintering and reviving periods under RFPM can achieve better source‐sink balance relationships and the maximum grain yield of winter wheat. Overall, we believe that in most cases, wheat yields are source‐limited and can be improved by ridge‐furrow planting with plastic mulching, complementary irrigation, and planting density regulation.

Investigation of Physiomorphological Characteristics of Sirvan Wheat Cultivar Using Amendment Materials

In order to investigate the effect of some amendment materials on physiomorphological characteristics of the Sirvan wheat cultivar, a randomized complete block design experiment and replicated three times, was carried out in the years 2018-2019 on a farm in Dasht-e Armou, Dareshahr Ilam Province, Iran. The aim of this study was to investigate and compare the effects of two factors, namely the type of amendment materials and the number of insoluble matters (alfalfa residues at 5, 10, and 15 t/ha, straw and wheat straw at 5, 10 and 15 t/ha, poultry manure at 2, 4 and 6 t/ha and the required 100-percent mineral fertilizer) on the plant. The results showed that the use of amendment materials significantly increased the number of spikes (15 to 143 percent), chlorophyll index (18 to 122 percent), number of leaves (8 to 51 percent), relative water content (6 to 21 percent), plant height (5 to 16 percent) and leaf area index (5 to 33 percent) of wheat. The highest number of leaves (19), plant height (115 cm), leaf area index (5.76), and relative water content (70 percent) were observed in 15 t/ha of alfalfa residues while the highest number of spikes (5.67) and chlorophyll index leaf (18.6) was obtained in 6 t/ha of poultry manure. Based on findings, it can be stated that the use of amendment materials, especially in raw form and poultry manure, will have beneficial effects on the growth and yield of wheat.

Glial Response and Neuronal Modulation Induced by Epidural Electrode Implant in the Pilocarpine Mouse Model of Epilepsy.

In animal models of epilepsy, cranial surgery is often required to implant electrodes for electroencephalography (EEG) recording. However, electrode implants can lead to the activation of glial cells and interfere with physiological neuronal activity. In this study, we evaluated the impact of epidural electrode implants in the pilocarpine mouse model of temporal lobe epilepsy. Brain neuroinflammation was assessed 1 and 3 weeks after surgery by cytokines quantification, immunohistochemistry, and western blotting. Moreover, we investigated the effect of pilocarpine, administered two weeks after surgery, on mice mortality rate. The reported results indicate that implanted mice suffer from neuroinflammation, characterized by an early release of pro-inflammatory cytokines, microglia activation, and subsequent astrogliosis, which persists after three weeks. Notably, mice subjected to electrode implants displayed a higher mortality rate following pilocarpine injection 2 weeks after the surgery. Moreover, the analysis of EEGs recorded from implanted mice revealed a high number of single spikes, indicating a possible increased susceptibility to seizures. In conclusion, epidural electrode implant in mice promotes neuroinflammation that could lower the seizure thresholds to pilocarpine and increase the death rate. An improved protocol considering the persistent neuroinflammation induced by electrode implants will address refinement and reduction, two of the 3Rs principles for the ethical use of animals in scientific research.

Spike-Based Neuromorphic Hardware for Dynamic Tactile Perception with a Self-Powered Mechanoreceptor Array.

A self-powered mechanoreceptor array is demonstrated using four mechanoreceptor cells for recognition of dynamic touch gestures. Each cell consists of a triboelectric nanogenerator (TENG) for touch sensing and a bi-stable resistor (biristor) for spike encoding. It produces informative spike signals by sensing a force of an external touch and encoding the force into the number of spikes. An array of the mechanoreceptor cells is utilized to monitor various touch gestures and it successfully generated spike signals corresponding to all the gestures. To validate the practicality of the mechanoreceptor array, a spiking neural network (SNN), highly attractive for power consumption compared to the conventional von Neumann architecture, is used for the identification of touch gestures. The measured spiking signals are reflected as inputs for the SNN simulations. Consequently, touch gestures are classified with a high accuracy rate of 92.5%. The proposed mechanoreceptor array emerges as a promising candidate for a building block of tactile in-sensor computing in the era of the Internet of Things (IoT), due to the low cost and high manufacturability of the TENG. This eliminates the need for a power supply, coupled with the intrinsic high throughput of the Si-based biristor employing complementary metal-oxide-semiconductor (CMOS) technology.

Wheat yield and grain-filling characteristics due to cultivar replacement in the Haihe Plain in China.

The Haihe Plain plays an important role in wheat production and food security in China and has experienced continuous cultivar replacement since the 1950s.This study assessed the evolution of the yield and grain-filling characteristics of the main winter wheat cultivars in the Haihe Plain over the last seven decades (1950s to date). Cultivar characterization indicated that the increase in yield was negatively affected by spike number and positively affected by the number of kernels per spike before the 2000s and kernel weight after the 2000s. Field trials were conducted across two ecological zones over two consecutive wheatgrowing seasons. The results showed that genetic gains in grain yield, spike number, and kernel weight during 1955 to 2021 were 0.629%, 0.574%, and 0.332% year-1 on a relative basis or 39.12 kg ha-1, 24,350 hm-2, and 0.15 g year-1 on an absolute basis, respectively. However, the increase in the kernel number per spike was not significant. Moreover, cultivar replacement explained 25.6%, 12.8%, and 37.5% of the total variance in grain yield, spike number, and kernel weight, respectively. In summary, during the initial grain-filling stage, wheat cultivar replacement led to the shortening of grain-filling duration and rapid grain-filling rate. However, a longer active grain-filling duration was produced by prolonged durations of rapid and late grain-filling. Additionally, the experimental year had a greater effect on the kernel number, which explained 53.2% of the total variance. Ultimately, modern wheat cultivars had a greater kernel weight. Although the increase in kernel weight has affected grain yield during cultivar replacements in the Haihe Plain, the potential for further yield increase through kernel weight enhancement alone is limited. Consequently, future breeding efforts and cultivation practices should focus on improving spike traits and canopy architecture to enhance productivity.

Improvement of grain weight and crop water productivity in winter wheat by light and frequent irrigation based on crop evapotranspiration

Efficient use of scarce water resources to maximize yield and crop water productivity (WPc) is a common goal of sustainable and ecological agriculture in the North China Plain. To clarify whether light and frequent (LF) irrigation under the same or reduced amount of irrigation is beneficial to achieve this goal, and to further tap the water saving potential. Based on drip irrigation conditions, a three–year (2020–2023) field experiment was conducted to investigate the effect of four irrigation treatments (CK, conventional irrigation at the jointing and anthesis stages; LF1, 100 % ETc, ETc is the crop evapotranspiration; LF2, 75 % ETc, LF3, 50 % ETc) on yield, water consumption characteristics, leaf photosynthetic physiology and grain filling process. The results showed that compared with CK, LF1 and LF2 significantly increased the photosynthetic rate and chlorophyll content of flag leaves at 18 days after anthesis, promoted grain filling, and finally enhanced dry matter accumulation after anthesis, 1000–grain weight (TGW) and grain yield. LF irrigation management mode also increased the consumption of deep soil water (1.4–2.0 m), reduced soil water consumption and evapotranspiration, and significantly improved WPc and irrigation water productivity. However, LF1 and LF2 did not have significant yield enhancement in the wet year, but had one less irrigation than in the normal year. The LF2 achieved the highest WPc in three years (2.1 kg m–3), in the 25 % (37.5 mm) and 40 % (60 mm) less irrigation water in the normal and wet years, respectively. Meanwhile, the LF3 treatment reduced the number of spikes, TGW and dry matter accumulation to different degrees in three years, resulting in significantly lower yields (13.9 %–18.4 %), which cannot be used as a reference for an efficient irrigation system. Therefore, LF irrigation based on 75 % ETc is the best irrigation strategy to improve water utilization and yield in the North China Plain.

Oil-Coated Ammonium Sulfate Improves Maize Nutrient Uptake and Regulates Nitrogen Leaching Rates in Sandy Soil

Ammonium sulfate (AS) has been utilized in agriculture; however, there is a dearth of research on its application in maize cultivation subsequent to the implementation of nitrification inhibitors or coating treatments. This study aimed to analyze the impacts of various combinations of AS fertilizers on soil nutrients, plant nutrient uptake, yield, and fertilizer utilization efficiency in maize cultivation to establish an optimal and stabilized disposal method for AS. A completely randomized design was employed with five treatments (AU, the control using urea; AS, treatment using ammonium sulfate; ASN, treatment using ammonium sulfate with a nitrification inhibitor; ASG, treatment using oil-coated ammonium sulfate; and ASD, treatment using oil–humic acid-coated ammonium sulfate). The results show the following: (1) Compared with AU and AS, ASN, ASG, and ASD decreased the leaching rates of total nitrogen (TN), ammonium nitrogen (NH4+-N), and nitrate nitrogen (NO3−-N), and more residual N had accumulated in the soil. The first-order kinetic equation Nt = N0(1 − e−kt) could better fit the process of N accumulation and release, and the N-release rate constant was in the order of AU > CK > AS > ASG > ASN > ASD. (2) Compared with the AU and AS treatments, the plant dry weight, grain dry weight, spike width, spike length, and yields of maize increased by 8.85–11.08%, 12.98–14.15%, 2.95–3.52%, 5.50–5.65%, and 43.21–51.10%, respectively, under the ASG treatment. A path analysis revealed the main decision coefficient of the effective spike number on the maize yield. Furthermore, the accumulation levels of N, P, and K within above-ground plants significantly increased under the ASG treatment compared with those under the AU and AS treatments. N, P, and K partial factor productivity under the ASG treatment increased by 47.12%, 47.15%, and 73.40% on average, while grain N, P, and K balance increased by 50.45%, 47.10%, 55.61% on average, compared with the AU and AS treatments. Therefore, the ASG treatment exhibited the optimal slow-release effect on nutrients and achieved excellent performance in enhancing the production and efficiency of maize.

Spectral-genomic chain-model approach enhances the wheat yield component prediction under the Mediterranean climate.

In light of the changing climate that jeopardizes future food security, genomic selection is emerging as a valuable tool for breeders to enhance genetic gains and introduce high-yielding varieties. However, predicting grain yield is challenging due to the genetic and physiological complexities involved and the effect of genetic-by-environment interactions on prediction accuracy. We utilized a chained model approach to address these challenges, breaking down the complex prediction task into simpler steps. A diversity panel with a narrow phenological range was phenotyped across three Mediterranean environments for various morpho-physiological and yield-relatedtraits. The results indicated that a multi-environment model outperformed a single-environment model in prediction accuracy for most traits. However, prediction accuracy forgrain yield was not improved. Thus, in an attempt to ameliorate the grain yield prediction accuracy, we integrated a spectral estimation of spike number, being a major wheat yield component, with genomic data. A machine learning approach was used for spike number estimation from canopy hyperspectral reflectance captured by an unmanned aerial vehicle. The spectral-based estimated spike number was utilized as a secondary trait in a multi-trait genomic selection, significantly improving grain yield prediction accuracy. Moreover, the ability to predict the spike number based on data from previous seasons implies that it could be applied to new trials at various scales, even in small plot sizes. Overall, we demonstrate here that incorporating a novel spectral-genomic chain-model workflow, which utilizes spectral-based phenotypes as a secondary trait, improves the predictive accuracy of wheat grain yield.

Genetic Variability and Character Association Analysis in Wheat (Triticum aestivum L.) in Saline Water Condition

The study was conducted to evaluate eight germplasms/varieties of wheat during the rabi season (November-April, 2022–23) using a randomized block design with three replications at the research farm of Agricultural Research Sub-Station (ARSS), Nagaur (Rajasthan), India to estimate the variability parameters and characters association for nine characters. The results were revealed that mean sum of squares due to genotypes showed significant differences for all the nine characters under study, suggested that the genotypes were genetically divergent. The phenotypic coefficient of variation values was higher than genotypic coefficient of variation values for all the nine traits which reflect the influence of environment on the expression of traits. Spike length and number of spikelets were showed higher PCV and medium GCV. High heritability estimates were recorded for all the nine characters. High genetic advance as percentage of mean along with high heritability was observed for number of spikelets, spike length, number of effective tillers plant-1, seed yield and number of grains spike-1. This indicated the existence of lesser environmental influence and prevalence of additive gene action in their expression and these traits possessed high selective value. These characters could be further improved through individual plant selection. Grain yield had highly significant and positive genotypic and phenotypic correlations with plant height, number of effective tillers plant-1, spike length, number of spikelets and number of grains spike-1. These characters can be considered as criteria for selection for higher grain yield as these were mutually and directly associated with grain yield.

Growth and yield response of four bread wheat cultivars, (Triticum aestivum L.), to spraying with NPK nano fertilizer

Abstract A field experiment was carried out during the agricultural season 2021-2022 in two locations within the administrative borders of Nineveh Governorate, the first location in the Gleokhan area within the borders of Mosul Center and the second location within the administrative borders of Namrod district, which is 45 km from the center of Mosul district, in order to know the effect of the balanced NPK 20:20:20 compound fertilizer nano the growth and yield of four varieties of bread wheat. The global experiment was carried out, which consisted of two factors, a randomized complete block design, and three replications. The first factor was fertilizer levels with four levels (1, 2, and 3 gm.L-1) added in two phases. The first is in the tillers stage (Z 2-1) and the second stage is at the beginning of the boating stage (Z 4-0) on the Zadoks scale, in addition to the comparison treatment, which was the traditional farmer’s method of fertilization (adding urea and dab fertilizer according to the times and quantities recommended by the Ministry Iraqi Agriculture), the second factor, four varieties of local bread wheat (Bhoth 22, Abu Ghraib, Rashid and Jihan), the following characteristics were studied: plant height, number of tillers, flag leaf area, total chlorophyll content of flag leaf, number of days up to 50% flowering, number of spikes, spike length, number of grains per spike, grain yield, weight of 1000 grains. The most important results of the study were as follows: The comparison treatment (the traditional farmer's method) excelled in the total chlorophyll content of the Gleokhan site and in the number of spikes and weight of 1000 grains in the Namrod site, with values of (28.41 Spad, 267.75 spikes.m-2, and 44.91 g), respectively. The 1 g spray treatment excelled in the characteristics of the number of tillers, number of spikes, length of spike, grain yield, and weight of 1000 grains at the Gleokhan site, and in the two characteristics of leaf area and spike length at the Namrod site, with averages of (178.17 tiller.m-2, 100.08 spikes.m-2, 8.58 cm , 128.83 g.m-2, 35.20 g, 34.46 cm2 and 10.85 cm) in the aforementioned order. The 3 g spray treatment was superior in the characteristics of plant height for both sites, the number of days up to 50% flowering, and grain yield of the Namrod site, with rates of (54.42 cm, 80.77 cm, 135.83 days, and 332.17 g.m-2), respectively. No significant differences were recorded between the levels of fertilizer in terms of flag leaf area and number of days up to 50% flowering for Gleokhan site and number of grains per spike for both sites. The cultivar Bhoth 22 excelled in terms of total chlorophyll content and the weight of 1000 grains at the Gleokhan site, and for the characteristics of the number of tillers, number of days up to 50% flowering, number of spikes, and grain yield of the Namrod site, as averages were recorded (27.29 Spad, 34.23 g, 302.75 tiller.m-2, 134.92 days, 290.17 spike.m-2 and 405.42 g m-2) respectively. The Abu Ghraib cultivar achieved superiority in the number of grains per spike at Al-Namrod site, with an average of (46.43 grains.spike-1). The cultivar Rashid excelled in the characteristics of the number of tillers, number of spikes, and spike length at the Gleokhan site, and for the two characteristics of the flag leaf area and spike length at the Namrod site, where the rates were recorded (169.08 tiller.m-2, 104.58 spike.m-2, 8.56 cm, 34.55 cm2 and 12.98 cm), respectively. The cultivar Jihan achieved superiority in the two characteristics of the number of days up to 50% flowering and grain yield at Gleokhan site, with values of (131 days and 108.08 g.m-2), respectively. No significant differences were recorded between the cultivars included in the study in the characteristics of plant height, flag leaf area, number of grains per spike for Gleokhan site, and for the two characteristics of total chlorophyll content and weight of 1000 grains for Namrod site. The interaction of 1 g spray treatment with Jihan cultivar recorded the highest average grain yield at Gleokhan site, and the 3 g spray treatment with Bhoth 22 cultivar had the highest average grain yield at Namrod site with values of (301 and 487.67 g.m-2), respectively.

Deep tillage combined with straw biochar return increases rice yield by improving nitrogen availability and root distribution in the subsoil

ContextAfter over 20 years of practicing shallow rotary tillage combined with straw direct return in the middle and lower Yangtze regions of China, the yield potential has gradually disappeared, and new alternative tillage practices are required to continuously increase rice yield. ObjectiveThis paper investigates the yield effect and mechanism of deep tillage combined with straw return through two consecutive years of a field experiment. MethodsThree tillage depths (shallow tillage 6–7 cm, ST; medium tillage 12–14 cm, MT; and deep tillage 25–28 cm, DT) plus three straw management methods (no straw return, NR; straw direct return, SR; and straw biochar return based on the same amount of carbon input as SR, BR) were set up as experiment treatments. The aboveground and belowground growth traits of rice and soil nitrogen (N) status were determined. ResultsCompared with ST and MT, the DT enlarged rice root distribution and increased soil N content in the middle and lower soil layers (7–28 cm) and decreased the root–shoot ratio at the flowering stage, which was conducive to absorbing more soil nutrients from the subsoil and allocating more photosynthetic products to the aboveground parts and grain. The MT and DT increased spike number and rice yield compared with ST. Compared with NR, both SR and BR increased soil total and available N contents, and the remaining soil available N content at the harvest stage of BR was lower than that of SR. Straw return (SR and BR) improved rice yield by increasing spike number and kernels per spike, and the effect of BR on increasing rice yield was greater than that of SR. ConclusionsThe DT combined with BR increased root distribution and N content in the subsoil, promoted the utilization of subsoil's nutrients, and increased rice yield. It is therefore a promising tillage practice for achieving high rice yields.

Performance evaluation of advanced durum wheat genotypes under irrigated condition at Bhairahawa, Nepal

A field research was carried out at the National Wheat Research Program (NWRP) in Bhairahawa, Nepal in 2022 to investigate elite durum wheat genotypes and key traits contributing to grain yield. The experiment was performed in an alpha lattice design with two replications. Thirty distinct durum wheat genotypes were assessed, focusing on fourteen quantitative traits including days to booting, days to heading, days to maturity, plant height, spike length, peduncle length, number of tillers per square meter, number of spikes per square meter, number of grains per spike, grain weight per spike, thousand kernel weight, grain yield, biomass yield, chlorophyll content. The studied genotypes were grown under irrigated condition. Genotype NL1779 attained the highest grain yield of 3828 kg/ha, followed by NL1769 (3784 kg/ha), NL1772 (3726 kg/ha), NL1789 (3640 kg/ha) and NL1784 (3570 kg/ha). Principal components analysis revealed that eight traits were the major loadings on the first two principal components that describe 53.4% of the total morphological variance at irrigated condition. Cluster analysis grouped the different genotypes into four clusters, with each cluster showing variation in performance for different traits under irrigated conditions. Cluster III is characterized by genotypes exhibiting the highest grain yield, biomass yield, spike length, number of grains per spike, and number of spikes per square meter. Notably, the high-yielding genotypes NL1779, NL1769, NL1772, NL1789, NL1784, and NL1773 identified within this cluster could serve as potential candidates for inclusion in the national breeding program. These superior genotypes could be recommended for irrigated environment after further evaluation. Integrating them into national breeding programs offers an opportunity for genetic improvement, contributing to establishing a robust durum wheat production system in Nepal, meeting the growing demand for durum wheat products while promoting dietary diversity and sustainable agriculture.

Cortico-striatal action control inherent of opponent cognitive-motivational styles.

Turning on cue or stopping at a red light requires the detection of such cues to select action sequences, or suppress action, in accordance with cue-associated action rules. Cortico-striatal projections are an essential part of the brain's attention-motor interface. Glutamate-sensing microelectrode arrays were used to measure glutamate transients in the dorsomedial striatum (DMS) of male and female rats walking a treadmill and executing cued turns and stops. Prelimbic-DMS projections were chemogenetically inhibited to determine their behavioral necessity and the cortico-striatal origin of cue-evoked glutamate transients. Furthermore, we investigated rats exhibiting preferably goal-directed (goal trackers, GTs) versus cue-driven attention (sign trackers, STs), to determine the impact of such cognitive-motivational biases on cortico-striatal control. GTs executed more cued turns and initiated such turns more slowly than STs. During turns, but not missed turns or cued stops, cue-evoked glutamate concentrations were higher in GTs than in STs. In conjunction with turn cue-evoked glutamate spike levels, the presence of a single spike rendered GTs to be almost twice as likely to turn than STs. In contrast, multiple glutamate spikes predicted GTs to be less likely to turn than STs. In GTs, but not STs, inhibition of prelimbic-DMS projections attenuated turn rates, turn cue-evoked glutamate peaks, and increased the number of spikes. These findings suggest that turn cue-evoked glutamate release in GTs is tightly controlled by cortico-striatal neuronal activity. In contrast, in STs, glutamate release from DMS glutamatergic terminals may be regulated by other striatal circuitry, preferably mediating cued suppression of action and reward tracking.

A Grain Number Counting Method Based on Image Characteristic Parameters of Wheat Spikes

In order to measure wheat yield and wheat spike phenotypes, the grain number of wheat spikes is counted manually at present, but acquiring the grain number of wheat spikes is laborious and time-consuming. Counting the grain number of wheat spikes with an image processing method is promising, yet the application of this method is flawed due to its low accuracy. In this work, images of wheat spikes were collected and processed with technical procedures, including image cropping, image graying, histogram equalization, image binarization, eroding operation, removing small objects, filling image holes, revolving vertical spikes, cutting off stems, and removing stems. Wheat stems in binary images were eliminated by the sum pixels method, and the morphological characteristic parameters of the image areas of wheat spikes and lengths of wheat spike axes were calculated. Mathematical models relating the image areas of wheat spikes and lengths of the wheat spike axes to the grain number were established, and the mathematical models were verified. The results showed that the characteristic parameters of the image areas of wheat spikes and the lengths of the wheat spike axes for the spike images were linear relative to the grain number, and the maximum determination coefficients R2 were 0.9336 and 0.9012, respectively. The maximum determination coefficients R2 for the practical and predicted grain numbers were 0.9552 and 0.9369, respectively, and the minimum average absolute error was 2.3, while the average relative error for the mathematical models was 5.65%. The mathematical models relating the image areas of wheat spikes and the lengths of the wheat spike axes to the grain number were practical and accurate, and the mathematical model comparing the image area of wheat spikes and the grain number was superior to that comparing the length of the wheat spike axis and the grain number. The grain number of wheat spikes could be acquired accurately and quickly by the image processing method extracting the characteristic parameters of wheat spikes.

Studies on the Impact of Spacing, Pinching and Growth Retardants on Vegetative Growth and Flowering Behaviour of Salvia

The present investigation entitled “Studies on the impact of spacing, pinching and growth retardants on vegetative growth and flowering behaviour of Salvia” was conducted at College of Agriculture, Odisha University of Agriculture and Technology, Bhubaneswar, Odisha during December 2021 to April 2022. The experiment was laid out in a Factorial Randomized Block Design (FRBD) with three replications, comprising of 12 treatment combinations which includes the first factor spacing with two levels i.e., S1 (20 cm x 25 cm) and S2 (25 cm x 25 cm), second factor pinching with two levels i.e., P0 (no pinching) and P1 (pinching) and the third factor application of growth retardants with three levels i.e., G0 (control), G1 (CCC @500ppm) and G2 (MH @100ppm). The findings revealed that pinching and the application of growth retardants had a greater impact on critical flowering attributes than the spacing experimented with in this study. Treatment combination S2P1G1 i.e., T11 was proved to be better and yielded significant improvements. Based on the results it was concluded that pinching and application of CCC resulted in better growth and development in salvia regarding vegetative and flowering characters. Thus, the treatment combination S2P1G1 i.e., T11 was found to be superior for vegetative growth characters like plant height, the number of branches, the number of leaves and flowering characters like the number of flower spikes per plant, length of flower spike, and length of florets.

Semantic Segmentation of Solar Radio Spikes at Low Frequencies

Solar radio spikes are short lived, narrow bandwidth features in low frequency solar radio observations. The timing of their occurrence and the number of spikes in a given observation is often unpredictable. The high temporal and frequency of resolution of modern radio telescopes such as NenuFAR mean that manually identifying radio spikes is an arduous task. Machine learning approaches to data exploration in solar radio data is on the rise. Here we describe a convolutional neural network to identify the per pixel location of radio spikes as well as determine some simple characteristics of duration, spectral width and drift rate. The model, which we call SpikeNet, was trained using an Nvidia Tesla T4 16GB GPU with ~100000 sample spikes in a total time of 2.2 hours. The segmentation performs well with an intersection over union in the test set of ~0.85. The root mean squared error for predicted spike properties is of the order of 23%. Applying the algorithm to unlabelled data successfully generates segmentation masks although the accuracy of the predicted properties is less reliable, particularly when more than one spike is present in the same 64 X 64 pixel time-frequency range. We have successfully demonstrated that our convolutional neural network can locate and characterise solar radio spikes in a number of seconds compared to the weeks it would take for manual identification.

Improved YOLO-FastestV2 wheat spike detection model based on a multi-stage attention mechanism with a LightFPN detection head.

The number of wheat spikes has an important influence on wheat yield, and the rapid and accurate detection of wheat spike numbers is of great significance for wheat yield estimation and food security. Computer vision and machine learning have been widely studied as potential alternatives to human detection. However, models with high accuracy are computationally intensive and time consuming, and lightweight models tend to have lower precision. To address these concerns, YOLO-FastestV2 was selected as the base model for the comprehensive study and analysis of wheat sheaf detection. In this study, we constructed a wheat target detection dataset comprising 11,451 images and 496,974 bounding boxes. The dataset for this study was constructed based on the Global Wheat Detection Dataset and the Wheat Sheaf Detection Dataset, which was published by PP Flying Paddle. We selected three attention mechanisms, Large Separable Kernel Attention (LSKA), Efficient Channel Attention (ECA), and Efficient Multi-Scale Attention (EMA), to enhance the feature extraction capability of the backbone network and improve the accuracy of the underlying model. First, the attention mechanism was added after the base and output phases of the backbone network. Second, the attention mechanism that further improved the model accuracy after the base and output phases was selected to construct the model with a two-phase added attention mechanism. On the other hand, we constructed SimLightFPN to improve the model accuracy by introducing SimConv to improve the LightFPN module. The results of the study showed that the YOLO-FastestV2-SimLightFPN-ECA-EMA hybrid model, which incorporates the ECA attention mechanism in the base stage and introduces the EMA attention mechanism and the combination of SimLightFPN modules in the output stage, has the best overall performance. The accuracy of the model was P=83.91%, R=78.35%, AP= 81.52%, and F1 = 81.03%, and it ranked first in the GPI (0.84) in the overall evaluation. The research examines the deployment of wheat ear detection and counting models on devices with constrained resources, delivering novel solutions for the evolution of agricultural automation and precision agriculture.