Improvement Of Grain Yield Research Articles

Evaluate the Genetic Divergence and Principal Component Analysis in Bread Wheat (Triticum aestivum L.)

The current investigation was carried out on some bread wheat (Triticum aestivum L.) genotypes throughout spring season to evaluate their heat tolerance via Cluster Analysis and principal component analysis (PCA). The experiment was accomplished in an augmented block design with 60 genotypes and three replications. Evaluations were carried out on 26 quantitative traits. Cluster analysis showed five clusters, cluster I with 56 genotypes and clusters II, III, IV and V with only one genotype each. The clusters II, III, IV and V have only one genotype each, so their intra-cluster distances were zero. The intra-cluster distance for cluster I was 57.879. The maximum and minimum inter cluster distance was found between cluster II and III (267.377) and between cluster I and II (86.469), respectively. Cluster I showed the earliest (76.689 days) average for early maturity (days to 50% heading) and cluster III showed the maximum (27.664) average for grain yield (grain yield per plant). PCA indicated that the five principal components (PC1 to PC5) accounted for 65.61% of the total variance. PC1 accounted for 11.51% of the total variance and showed positive factor loading for almost traits. Harvest index, grain yield per plant, flag leaf width and leaf rolling showed the highest factor loadings for PC1. As a result of the foregoing data and analysis, it is possible to conclude that there is great potential for effective genetic improvement for grain yield and correlated traits in the present wheat genotypes.

Assessment of Heterosis and inbreeding Depression for Yield, and its Associated Components Traits in Rice (Oryza sativa L.)

The present investigation entitled was carried out at Main Rice Research Centre, Navsari Agricultural University, Navsari during kharif-2023 with an objectives to obtain information on manifestation of heterosis and extent of inbreeding depression involved in the inheritance of various yield attributing characters in rice (Oryza sativa L.). This study comprised three crosses using four diverse lines. The experimental material comprised of five generations each cross of pair parents i.e. P1, P2, F1, F2 and F3 of three different crosses were conducted in Compact Family Block Design with three replications during kharif 2023. For grain yield per plant all the three crosses (IRBB 55 × Mahisagar, IRBB 55 × GR-11 and IRBB 55 × TN-1) exhibited significant and positive relative heterosis as well as heterobeltiosis. Among them the highest mid parent heterosis of 39.67% and heterobeltiosis of 7.56% were exhibited by cross IRBB 55 × GR-11. This hybrid showed positive and significant relative heterosis for all the four important characters viz., productive tillers per plant, panicle length, grains per panicle and 100 grain weight. While, the inbreeding depression was found significant and positive for all the three crosses which is not desirable for grain yield per plant. Here, all the three crosses exhibited positive heterosis followed by positive inbreeding depression indicated that trait is under influence of non-additive type of gene action and heterosis breeding would be found rewarding for improvement for grain yield per plant.

Teosinte-Derived Advanced Backcross Population Harbors Genomic Regions for Grain Yield Attributing Traits in Maize

Maize is a highly versatile crop holding significant importance in global food, feed and nutritional security. Grain yield is a complex trait and difficult to improve without targeting the improvement of grain yield attributing traits, which are relatively less complex in nature. Hence, considering the erosion in genetic diversity, there is an urgent need to use wild relatives for genetic diversification and unravel the genomic regions for grain yield attributing traits in maize. Thus, the current study aimed to identify quantitative trait loci (QTLs) linked with grain yield and yield attributing traits. Two BC2F2 populations developed from the cross of LM13 with Zea parviglumis (population 1) and LM14 with Zea parviglumis (population 2) were genotyped and phenotyped in field conditions in the kharif season. BC2F2:3 lines in both populations were phenotyped again for grain yield and attributing traits in the spring season. In total, three QTLs each for ear height (EH), two QTLs for flag leaf length (FLL) and one QTL each for ear diameter (ED), plant height, flag leaf length (FLL), flag leaf width and 100 kernel-weight were identified in population 1. In population 2, two QTLs for kernel row per ear (KRPE) and one QTL for FLL were detected in. QTLs for EH, FLL and KPRE showed consistency across seasons. Among the identified QTLs, six QTLs were found to be co-localized near identified genomic regions in previous studies, validating their potential in contributing to trait expression. The identified QTLs can be utilized for marker assisted selection, transferring favorable alleles from wild relatives in modern maize.

Drought Priming Promotes Nitrogen Use Efficiency in Wheat (Triticum aestivum L.) Under Drought Stress During Grain Filling

ABSTRACTDrought stress significantly challenges wheat production globally, and drought priming has emerged as an effective strategy to mitigate yield loss under drought stress events. However, the effect of drought priming on plant nitrogen use efficiency (NUE) remains insufficiently understood. This study investigates the effects of drought priming at the six‐leaf stage on NUE under drought stress during grain filling in four wheat varieties with distinct responses to drought priming. Our results indicate that there is no correlation between inherent drought tolerance and the effects of drought priming among the wheat varieties studied. In priming‐sensitive varieties, drought‐primed plants exhibited significant improvements in grain yield and NUE under drought stress compared to non‐primed plants. Conversely, priming‐insensitive varieties showed no significant differences in yield or NUE between primed and non‐primed plants under similar conditions. Notably, under drought stress, primed plants exhibited higher yield and NUE than non‐primed plants in drought priming positive variety, while the opposite trend was observed in drought priming negative response variety. The enhancement of NUE through drought priming was associated with improved nitrogen uptake efficiency and its allocation to spikes, with abscisic acid accumulation playing a pivotal role. These findings provide valuable insights into the mechanisms by which drought priming enhances NUE under drought stress, contributing to the development of sustainable agricultural practices amid climate change.

Comparison of Agronomic and Physiological Characteristics for Rice Varieties Differing in Water Use Efficiency under Alternate Wetting and Drying Irrigation

Rice (Oryza sativa L.) stands as one of the most critical staple crops globally, with its yield and water use efficiency (WUE) being pivotal for food security. This study aimed to evaluate the agronomic and physiological traits and WUE of six rice varieties under two irrigation regimes: alternate wetting and drying (AWD) and conventional irrigation (CI). The results showed the significant improvements in grain yield and WUE with variety improvement under both irrigation treatments. Under AWD, high water use efficiency varieties (HWVs) demonstrated pronounced enhancements, including tillers and spikelet production, filled grain rate, 1000-grain weight, harvest index, leaf area index, non-structural carbohydrate remobilization, photosynthesis and catalase and peroxidase activities of leaf, root and shoot biomass, and root activity. AWD was observed to synchronize and amplify grain yield (2–14%) and WUE, including both leaf-level (13.94–20.72%) and yield-level (23.20–30.87%) water use efficiencies (WUEL and WUEY). The water use potential for HWVs was substantially enhanced under AWD. The integration of variety improvement with AWD irrigation strategies effectively achieves the dual objectives of high yield and WUE, offering a promising approach for sustainable rice production.

Studies on Estimates of Heritability and Genetic Advance for Certain Quantitative Traits in Fieldpea (Pisum sativum L. var. arvense)

Twenty two field pea genotypes were evaluated for estimation of variability, heritability and genetic advance. The Fieldpea genotypes were sown in, Randomized Block Design with three replications at the experimental farm of department of Genetics and Plant Breeding, Faculty of Agriculture, Kamla Nehru Institute of Physical and Social Sciences Sultanpur 228118 (U.P.) India, during Rabi, season 2022-2023. Phenotypic data were recorded for nine characters viz. days to 50% flowering, days to maturity, plant height, number of branches per plant, number of pods per plant, 100-grain weight, grain yield per plant and biological yield per plant. It was reported that in general the value of phenotypic coefficient of variance (PCV) is slightly higher than the value of genotypic coefficient of variance (GCV) indicating the importance of environment in the phenotypic performance of the genotypes studied. The maximum value of GCV was observed for plant height (31.94), grain yield per plant (20.02). High estimates of heritability in broad sense (h2b) were recorded for plant height (97.28), days to 50% flowering (83.96), 100-grain weight (78.48) and days to maturity (64.83). High estimates of genetic advance as percent of mean were recorded for plant height (64.89), 100-grain weight (25.28) and grain yield per plant (25.15). Thus, the characters (plant height, days to 50% flowering, 100-grain weight etc) having high value of GCV, heritability as well as genetic advance may be exploited in Fieldpea breeding program for further improvement in grain yield.

Defining the target population of environments for wheat (Triticum aestivum L.) breeding in Italy based on historical data

AbstractGrain yield plateau is a serious concern in many countries, including Italy. A specific‐adaptative strategy might apply to contrast this unfavourable condition. This study aimed to investigate the gain in grain yield and yield‐related traits of bread wheat in Italy over a 16‐year period. A historical dataset concerning 105 sites across Italy and observations on grain yield, heading date, plant height and thousand kernel weight was used. The target population of environments (TPEs) were defined using several environmental parameters. The results showed that while there was a general increase in thousand kernel weight over the 16 years, there was no significant improvement in grain yield and heading date. By contrast, plant height showed a slight decrease over the years. The study also identified five TPEs presenting different climate scenarios in Italy. The TPEs showed varying levels of performance for the traits of interest, with the Po valley (TPE4) showing the highest values for grain yield and thousand kernel weight. The study also identified the best‐performing genotypes for each TPE, providing valuable insights for future wheat breeding programmes in Italy.

Drought tolerance improvement for grain yield of a modern rice variety based on morphological and physiological response

Growth of rice (Oryza sativa L.) is severely affected by drought stress, which leads to decreased rice production in rainfed ecosystems worldwide. Particularly, modern rice varieties are more susceptible to drought stress rather than traditional rice varieties. In the present study, a modern short-term rice variety, ADT37, abundantly cultivated in the Cauvery delta region of the southern part of India, was improved for grain yield by introducing qDTY1.1 through the conventional backcross method. Positive F1 progenies were identified using RM431 linked with qDTY1.1 in PCR amplification. In phenotypic selection, rice progenies with suitable plant height to avoid linkage drag as well as high degree of drought tolerance to manage the drought stress were selected and advanced through the backcrossing process up to the BC3 generation. Finally, two near isogenic lines with equal plant height to the recurrent parent and high degree of drought tolerance were selected. A positive effect of qDTY1.1 on plant height and fertile seeds was revealed. In the future, the selected superior near isogenic lines would be useful to rice researchers and farmers facing unexpected water crises. Moreover, the morphological marker associated with the performance of crops according to the intensity of stress will support climate resilient agriculture.

Correlation and Path Coefficient Analyses for Grain Yield and Its Contributing Traits in Bread Wheat (Triticum aestivum L. em. Thell)

The study on bread wheat for fourteen characters viz., days to heading (50%), days to maturity, plant height (cm), number of productive tillers per plant, chlorophyll content , spike length (cm), number of spikelets per spike, number of grains per spike, weight of grain per spike(g), 1000 grain weight (g), biological yield (g), harvest index (%),protein content (%) and grain yield per plant (g) was conducted by making crosses among ten diverse genotypes in half diallel fashion grown in Randomized Block Design in three replication during Rabi 2022-2023 at SIF, C. S. Azad University of Agriculture & Technology, Kanpur, U.P. to assess the correlation and path coefficient. At genotypic level grain yield per plant showed positive and significant correlation with biological yieldper plant followed by number f productive tillers per plant, weight of grain per spike, harvest index, 1000 grain weight, chlorophyll content and days to maturity. In F2 generation correlation coefficients at genotypic level higher than the corresponding phenotype correlation coefficient for all characters and eight characters viz., biologic yield per plant, weight of grain per spike, number of productive tillers per plant, harvest index, 1000 grain weight, days to maturity, protein content and number of grain per spike showed positive and significant correlation with grain yield per plant. At genotypic level the highest positive direct effect on grain yield per plant was exerted by biological yield per plant followed by harvest index, number of spikelets per spike, spike length, days to 50% heading, 1000 grain weight, number of productive tiller per plant, weight of grain per spike, chlorophyll content and protein content in F1s.At phenotypic level the highest positive direct effect on grain yield per plant was exerted by biological yield per plant followed by harvest index, spike length, days to maturity, number of productive tiller per plant, weight of grain per spike, chlorophyll contend and protein content in F2s. Hence these characters may be considered for selection and improvement of grain yield in bread wheat.

Selection of extra-early white quality protein maize (Zea mays L.) inbred lines for drought and low soil nitrogen resilient hybrid production

In West and Central Africa (WCA), drought and low soil nitrogen (low N) impede increased maize (Zea mays L.) productivity and production. Due to climate change, the two stresses usually occur together, leading to food, nutritional, and economic insecurity in the sub-region. There is, therefore, the need for the development and availability of high-yielding extra-early maturing white Quality Protein Maize (QPM) synthetics and hybrids with resilience to the prevailing stresses through the identification of superior climate smart (extra-early maturing) QPM inbreds under stress (drought and low soil N) conditions. The study was conducted to identify stress-resilient QPM inbred lines for hybrid production and assess the association between grain yield and other studied characters. During the 2012 minor and major rainy seasons, 96 extra-early white QPM inbreds and four (4) normal endosperm maize inbred checks were assessed in multi-location trials under stress and optimal conditions in Nigeria. The experiments were laid out in a 10 × 10 simple lattice design with two replications. Data were recorded on grain yield and other agronomic traits. Significant variations (p < 0.01) were detected among the inbred lines for measured characters, indicating adequate genetic variability among the inbreds to allow for selection and improvement of grain yield and other measured traits. Grain yield was interrelated with all the traits used in the selection index. Moderate to high estimates of heritability were observed for most of the measured traits under stress conditions, indicating that the traits could be easily transmitted to the progenies. Fifty-seven out of the 96 QPM inbreds evaluated exhibited varying degrees of resilience to drought and low N. The QPM inbreds with desired traits may be used as genetic resources for the incorporation of tolerance genes into QPM populations in the tropics, as well as for the development of drought and low N resilient synthetics and hybrids in WCA.

Auxin synthesis promotes N metabolism and optimizes root structure enhancing N acquirement in maize (Zea mays L.).

Foliar NAA increases photosynthate supplied by enhancing photosynthesis, to strengthen root activity and provide a large sink for root carbohydrate accumulation, which is beneficial to acquire more nitrogen. The improvement of grain yield is an effective component in the food security. Auxin acts as a well-known plant hormone, plays an important role in maize growth and nutrient uptake. In this study, with maize variety Zhengdan 958 (ZD958) as material, the effects of auxin on nitrogen (N) uptake and assimilation of seedling maize were studied by hydroponic experiments. With water as the control, naphthalene acetic acid (NAA, 0.1mmol/L) and aminoethoxyvinylglycine (AVG, 0.1mmol/L, an auxin synthesis inhibitor) were used for foliar spraying. The results showed that NAA significantly improved photosynthetic rate and plant biomass by 58.6% and 91.7%, respectively, while the effect of AVG was opposite to that of NAA. At the same time, key enzymes activities related N assimilation in NAA leaves were significantly increased, and the activities of nitrate reductase (NR), glutamine synthetase (GS) and glutamate synthase (GOGAT) were increased by 32.3%, 22.9%, and 16.2% in new leaves. Furthermore, NAA treatment promoted underground growth. When compared with control, total root length, root surface area, root tip number, branch number and root activity were significantly increased by 37.8%, 22.2%, 35.1%, 28.8% and 21.2%. Root growth is beneficial to N capture in maize. Ultimately, the total N accumulation of NAA treatment was significantly increased by 74.5%, as compared to the control. In conclusion, NAA foliar spraying increased endogenous IAA content, and enhanced the activity of N assimilation-related enzymes and photosynthesis rate, in order to build a large sink for carbohydrate accumulation. In addition, NAA strengthened root activity and regulated root morphology and architecture, which facilitated further N uptake and plant growth.

Synthesis, characterization and evaluation of novel manganese nanoclay polymer composite and nano‐MnO2 in wheat

AbstractBackgroundManganese (Mn) deficiency due to nutrient mining by high yielding cereal–cereal cropping patterns and forgetfulness of Mn fertilizer applications becomes potential challenge in crop production.AimNano‐enabled Mn fertilizers can be safer and more nutrient efficient than conventional Mn fertilizers (nutrient use efficiency ≈ 1%–3%). However, studies about nano‐Mn fertilizer synthesis and their behaviour in soil–plant system are rare.MethodsIn this study, two novel nano‐Mn fertilizers, that is nano‐MnO2 (NMO) and manganese nanoclay polymer composites (Mn‐NCPC), were synthesized, characterized (dynamic light scattering, X‐ray diffraction, Scanning electron microscopic and energy‐dispersive X‐ray, Fourier transform infrared spectroscopy etc.) and investigated for their impact on growth, yield and nutrient acquisition by wheat crop (Triticum aestivum L., variety HD‐2967) in a pot culture experiment. Treatment comprised 25%, 50% and 100% of recommended dose of Mn (RDMn) through NMO along with 100% RDMn through MnSO4·H2O (MS). Effect of exposure route was also investigated using foliar spray of NMO at tillering stage. Mn‐NCPC was found to be most efficient Mn fertilizer in terms of yield, Mn uptake and use efficiency by wheat crop.ResultsNano‐sized formulations improved the solubility of Mn in soil due to its higher active surface area (NMO) and slow‐release behaviour (Mn‐NCPC); thus, minimal losses happened due to the fixing of Mn in oxide/hydroxide forms. Application of 25% RDMn through NMO fertilizers maintained equitant diethylenetriamine pentaacetate Mn content to 100% RDMn through MnSO4·H2O. Mn‐NCPC stimulated the soil enzymatic activities, namely dehydrogenase, acid–alkaline phosphatase activities. Mn‐NCPC and NMO at 100% RDMn recorded 3.51% and 5.20% improvement in grain yield, respectively, when compared to MnSO4·H2O 100%.ConclusionsMn fertilizer doses can be reduced up to 25% of RDMn when applied through NMO or Mn‐NCPC fertilizers. However, effects of Mn‐NCPC and NMO need to be critically evaluated in long‐term field experiments in various cropping systems especially under cereal–cereal sequences for economic profitability and wide‐scale farmer's adaptability.

MSH7 confers quantitative variation in pollen fertility and boosts grain yield in maize.

Fertile pollen is critical for the survival, fitness, and dispersal of flowering plants, and directly contributes to crop productivity. Extensive mutational screening studies have been carried out to dissect the genetic regulatory network determining pollen fertility, but we still lack fundamental knowledge about whether and how pollen fertility is controlled in natural populations. We used a genome-wide association study (GWAS) to show that ZmGEN1A and ZmMSH7, two DNA repair-related genes, confer natural variation in maize pollen fertility. Mutants defective in these genes exhibited abnormalities in meiotic or post-meiotic DNA repair, leading to reduced pollen fertility. More importantly, ZmMSH7 showed evidence of selection during maize domestication, and its disruption resulted in a substantial increase in grain yield for both inbred and hybrid. Overall, our study describes the first systematic examination of natural genetic effects on pollen fertility in plants, providing valuable genetic resources for optimizing male fertility. In addition, we find that ZmMSH7 represents a candidate for improvement of grain yield.

Transforming Agriculture through Nanotechnology: A Comprehensive Overview

Nanotechnology has emerged as a transformative force in agriculture, offering innovative solutions to address critical challenges in food production, sustainability, and resource management. This comprehensive overview explores the multifaceted impact of nanotechnology on agriculture, providing insights into its potential to revolutionize the sector and by elucidating the fundamental principles of nanotechnology and its applicability in agriculture, emphasizing nanomaterials’ unique properties that enable precise manipulation at the molecular and nanoscale levels. It explores diverse applications, including nanoparticle-based nutrient delivery systems, nanoencapsulation for controlled release of agrochemicals, and the development of nanosensors for real-time monitoring of crop health and environmental parameters. Furthermore, this delves into the emerging field of precision farming enabled by nanotechnology, where data-driven decision-making and targeted interventions optimize resource utilization, minimize environmental impacts, and maximize crop yields. It examines the potential of nano pesticides in integrated pest management, highlighting their eco-friendly nature and reduced environmental contamination. Nanotechnology’s role in soil management and remediation is also discussed, showcasing its capacity to improve soil health, remediate contaminated lands, and enhance nutrient availability. The review sheds light on the application of nanofertilizers, which not only enhance nutrient use efficiency but also mitigate nutrient runoff, contributing to sustainable agriculture. While nanotechnology holds immense promise, it is imperative to consider safety and environmental implications. This examines the challenges and regulatory considerations surrounding the use of nanomaterials in agriculture, emphasizing the need for responsible development and rigorous risk assessment.

Evaluation of zinc application methods and integrated nutrient management on variation in growth, yield and yield contributing factors in wheat

Zinc is an important micro nutrient and plays an important role in improving the crop growth and productivity. Intensive agricultural practices due to rise in population have accelerated the use of chemical fertilizers which resulted in depletion of soil fertility. In this regard, a 2 year field experiment was conducted at Agricultural Research Farm of Lovely Professional University during rabi season in 2021-2022 and 2022-23 to examine the effect of different zinc application methods and integrated nutrient management on growth, yield and yield contributing factors on wheat. Three types of zinc application methods along with various levels of integrated nutrient management approaches were used for the study. The results revealed that a significant interaction between zinc application methods and integrated nutrient management practices was observed with dry matter accumulation (g/m2), Leaf area index, spikes/m2, spike length (cm), number of grains per spike and grain yield of wheat crop. Maximum improvement in grain yield (5.5 t/ha) was obtained when soil+foliar application of zinc was combined with 75% recommended dose of fertilizer + 2.5 t/ha farm yard manure + Zinc solubilizing bacteria. Additionally, these studies need to be repeated at many locations with various agro-climatic circumstances.

Physiological Analysis of Source-Sink Relationship in Rice Genotypes with Contrasting Grain Yields.

Rice is a major staple food, and, hence, doubling its productivity is critical to sustain future food security. Improving photosynthesis, source-sink relationships and grain-filling mechanisms are promising traits for improvement in grain yield. To understand the source-sink relationship and grain yield, a set of contrasting rice genotypes differing in yield and biomass were studied for physiological, biochemical and gene-expression differences. The physiological and yield component traits of selected rice genotypes were analyzed in 2016 and 2017 under field conditions. This led to the categorization of genotypes as high yielding (HY) and high biomass, viz., Dular, Gontra Bidhan 3, Way Rarem, Patchai Perumal, Sahbhagi Dhan, Indira Barani Dhan-1, MTU1010, and Maudamani; while, low yielding (LY) and low biomass, viz. Anjali, Ghanteswari, Parijat, Khao Daw Tai, RKVY-104, Ghati Kamma Nangarhar, BAM4510 and BAM5850. The HY genotypes in general had relatively better values of yield component traits, higher photosynthetic rate (Pn) and chlorophyll (Chl) content. The study revealed that leaf area per plant and whole plant photosynthesis are the key traits contributing to high biomass production. We selected two good-performing (Sahbhagi Dhan and Maudamani) and two poor-performing (Ghanteswari and Parijat) rice genotypes for a detailed expression analysis of selected genes involved in photosynthesis, sucrose synthesis, transport, and starch synthesis in the leaf and starch metabolism in grain. Some of the HY genotypes had a relatively high level of expression of key photosynthesis genes, such as RbcS, RCA, FBPase, and ZEP over LY genotypes. This study suggests that traits, such as leaf area, photosynthesis and grain number, contribute to high grain yield in rice. These good-performing genotypes can be used as a donor in a breeding program aimed at high yields in rice.

Correlation and Path Coefficient Studies of Three Line Rice Hybrids

Thirty-one three-line rice hybrids and three commercial checks were used in the current study for correlation and path coefficient analysis. In Kharif 2021, the experiment was carried out at the TCA Hybrid Rice field in Dholi, Pusa, Bihar, India. The experimental design adopted was a Randomized Complete Block Design (RBD) with three replications that included 18 quantitative attributes. Plant height, number of tillers per plant, number of panicles per plant, leaf length, leaf area, kernel length, kernel width, root fresh weight, root dry weight, spikelet fertility, and test weight showed a positive significant correlation with grain yield per plant. Hence, selection for any one of these characteristics would ultimately bring improvement in grain yield. The traits number of tillers per plant, plant height, root fresh weight, leaf length, no. of panicles per plant, leaf width, kernel length, and root volume revealed a significant direct impact on grain yield per plant. Thus, breeding for these characteristics could end up resulting in a higher grain yield.

Evaluation on Genetic Variation, Correlation and Path Analysis in Zaid Maize (Zea mays L.) for Quantitative Characters

The present investigation was carried out to evaluate genetic variability parameters, correlation and path analysis in twenty-one maize genotypes for 21 quantitative traits in Zaid 2023 at Field Experimentation Centre, Department of Genetics and Plant Breeding, Naini Agricultural Institute, Sam Higginbottom University of Agriculture Technology and Sciences, Uttar Pradesh in Randomized Block Design replicated thrice. Analysis of Variance for all characters revealed that treatment differences were highly significant under study at 1% level. Genotype MZ-1917 depicted highest grain yield in the grown environment. The values of PCV were higher than GCV values for all the characters and large differences PCV between the values of PCV and GCV of characters like number of leaves per plant, leaf length, tassel length, cob length, cob girth and shelling percentage indicating that environmental factors significantly influenced the expression of these traits. All the traits studied had higher heritability, high genetic advance coupled with high heritability was observed for anthesis-silking intervals, ear height, cob weight, number of kernels per row, shank weight, 100 kernels weight, biological yield and grain yield per plant indicating the presence of large proportion of additive genetic action deciding these traits. Correlation and path coefficient analysis suggest that selection based on characters cob length, cob weight, shank weight, 100 kernels weight had positive correlation and direct effects with grain yield per plant. Therefore, it concludes that effective selection must be attempted for these traits, which would help in improvement of grain yield in maize genotypes grown during Zaid season of eastern Uttar Pradesh.

Heritable variability in winter wheat at the interaction of genotype with factors of high genetic activity

Identification of new opportunities in the use of certain ecogenetic factors for the genetic improvement of winter wheat is a vital component of improving existing cereal agrocenoses within the framework of the food security strategy. The purpose of this study was to demonstrate the potential of substances with prominent genetic activity in inducing potentially beneficial changes and to establish the possibility of obtaining optimised schemes for obtaining new forms and more controlled trait variability. Mutations were detected by visual observation and biometric and biochemical analysis from the second generation to the sixth, with the inheritance of the detected traits in subsequent generations being checked. The study presented the possibilities of the mutation process for certain genetic and breeding-value forms, the specific features of induction of such traits, which makes it possible to increase the predictability of obtaining the necessary mutant lines and partially controlled high variability in certain traits. It was found that the most promising for use is the complex application of moderate doses of sodium azide and dimethyl sulphate as ecogenetic factors. It was shown that in combination with three varieties among the ones under study (Kalancha, Polyanka, Pochayna), it is possible to create highly efficient genotype-mutagenic systems with increased yield of valuable forms. The increase in mutagenic depression using more harmful substances can be substantially offset by an increase in the proportion of beneficial changes. The negative side is their complex nature. The nature of the ecogenetic factor is no less significant than the concentration of the mutagen or the genotype of the original form, which is sometimes overlooked. It was confirmed that the use of these factors is quite promising in terms of obtaining small biochemical changes (micromutations). Several promising mutant lines were identified that have a comprehensive improvement in grain yield and quality without additional negative changes. The findings of this study can be used in breeding programmes to create new varieties of winter wheat

Optimal nitrogen management to achieve high wheat grain yield, grain protein content, and water productivity: A meta-analysis

Nitrogen (N) addition is commonly employed to enhance wheat production, and the effectiveness is strongly influenced by site-specific factors encompassing environmental conditions and crop management practices. However, the current understanding fails to adequately account for the intricate and variable interactions among these factors. Consequently, we conducted a global meta-analysis to quantify the combined contributions of these factors to wheat yield, grain protein content (GPC), and water productivity (WP) and provide recommendations for optimizing N management. The results revealed a significant improvement in grain yield (14.85%), GPC (6.62%), and WP (10.79%) following the application of N. Moreover, higher N addition rates, the utilization of coated N fertilizer, post-anthesis fertilization, and multiple N applications exhibited enhanced outcomes in terms of yield, GPC, and WP in wheat systems. It was observed that applying 100–200 kg/ha of N was the optimal rate for maximizing yield, GPC, and WP. Medium soil texture and humid climate conditions showed a more pronounced increase in yield in response to N addition. Additionally, wheat yield demonstrated a stronger response to N addition benefits when the annual temperature was below 14 °C, while GPC showed a higher increase with temperatures exceeding 14 °C. Furthermore, adopting common N fertilization practices alongside irrigation and implementing pre-anthesis N addition in medium soil texture and humid climate conditions also contributed to achieving optimal wheat performance. The finding of this study serves as a guideline to support on-site N addition practice for wheat and to offer a reference to N management policy design across specific site conditions.