This Bachelor Thesis focusses on elucidating out superior genotypes for varietal development of maize, analyzing the correlation study of grain yield with other parameters and estimating the direct and indirect effects of various parameters on grain yield.
Maize was domesticated around 7000 years ago in Central Mexico. Maize belongs to family Poaceae and tribe Maydae. Maize is grown in different ranges of environment condition. Thus, through introduction and breeding, it has gained adaptation all over the world. The spread of maize cultivation in the world was due to its diversity, high adaptability and versatility. The reasons for its popularity include high yields per unit area, husk protection against birds and rain, fairly easy to weed as well as possession of a good competition rate with weeds because of its rapid vertical growth. In Nepal, maize is the second most important cereal crop in terms of area and production.
Farmers and breeders want successful new maize hybrids that show high performance for yield and other essential agronomic traits. Their superiority should be reliable over a wide range of environmental conditions. The basic cause of difference between genotypes in their yield stability is the occurrence of genotype-environment interaction (GEI). Genotype – environment interaction may be expected to be high when environmental differences are high as in Ghana. Hence, it is important to assess the importance of interactions in the selection of genotypes across several environments besides calculating the average performance of the genotypes under evaluation.
Table of Contents
1. INTRODUCTION
1.1 Background
1.2 1.2 Objectives
2. LITERATURE REVIEW
2.1 Variance analysis
2.2 Correlation
2.3 Path coefficient analysis
3. MATERIALS AND METHODS
3.1 Research site
3.2 Climatic condition and season
3.3 Experimental details/materials/selection of genotype
3.4 Data collection
3.5 Statistical Analysis
4. EXPERIMENTAL RESULTS
4.1 Mean performance of genotypes
4.2 Analysis of variance
4.3 Correlation studies
4.4 Path coefficient analysis
5. DISCUSSION
5.1 Variability
5.2 Association of characters
5.3 Path coefficient analysis
6. SUMMARY AND CONCLUSION
Research Objectives and Topics
This study aims to evaluate the performance of various maize genotypes to improve productivity in Nepal, specifically addressing the yield gap through the identification of superior varieties and the analysis of key agronomic traits and their associations with grain yield.
- Identification of high-performing maize genotypes for breeding and development.
- Statistical assessment of yield variability across different genotypes.
- Correlation analysis between grain yield and various morphological yield components.
- Determination of direct and indirect effects of agronomic traits on yield using path coefficient analysis.
Excerpt from the Book
1.1 Background
Maize (Zea mays L.) was domesticated around 7000 years ago in Central Mexico. Maize belongs to family Poaceae and tribe Maydae. Maize is grown in different ranges of environment condition. Thus, through introduction and breeding, it has gained adaptation all over the world. The spread of maize cultivation in the world was due to its diversity, high adaptability and versatility. The reasons for its popularity include high yields per unit area, husk protection against birds and rain, fairly easy to weed as well as possession of a good competition rate with weeds because of its rapid vertical growth.
In Nepal, maize is the second most important cereal crop in terms of area and production (Kandel et al., 2017; Kandel et al., 2018; Sharma et al., 2018; Thapa et al., 2019). Maize is grown in an area of 891583 ha with a total production of 2231517 metric tons and productivity of 2.503 ton/ha (MoAD, 2015/16). The contribution of maize to national GDP is 3.15% and to agricultural GDP is 9.5% (MoAD, 2013). Out of total maize cultivated area in Terai region, 95.95% area is under improved maize and 4.05% under local maize. In plain, it is grown as Rabi maize and spring maize with irrigation (Paudel et al., 2001). In Nepal, the productivity of maize is very low compared to other developed countries.
Summary of Chapters
1. INTRODUCTION: Provides the background of maize cultivation globally and specifically in Nepal, highlighting the need for improved varieties to overcome low productivity.
2. LITERATURE REVIEW: Summarizes previous research on variance analysis, character correlations in maize, and the application of path coefficient analysis.
3. MATERIALS AND METHODS: Describes the experimental site, climatic conditions, the ten maize genotypes used, and the statistical methods applied for data analysis.
4. EXPERIMENTAL RESULTS: Presents the findings regarding genotype performance, variance analysis, character correlations, and path coefficient results.
5. DISCUSSION: Interprets the results by comparing them with previous studies, focusing on variability, trait association, and the implications for selection.
6. SUMMARY AND CONCLUSION: Recaps the main findings of the research and suggests promising maize lines for future varietal development.
Keywords
Maize, Zea mays L., Genotypes, Grain yield, Path coefficient analysis, Correlation, Agronomic traits, Nepal, Breeding, Variability, Yield components, Selection, Plant height, Tasseling, Silking
Frequently Asked Questions
What is the primary focus of this research?
The research focuses on evaluating ten different maize genotypes to identify superior varieties that show stable and high performance in terms of grain yield and other agronomic traits under the environmental conditions of Nepal.
What are the central themes of this work?
The central themes include the assessment of genotypic variability, the study of character associations between yield and its components, and the determination of direct and indirect effects of these components on final grain yield.
What is the core research objective?
The primary objective is to elucidate superior maize genotypes for varietal development, analyze correlations between grain yield and other parameters, and estimate the direct and indirect influence of various morphological traits on grain yield.
Which scientific methods are utilized?
The study employs a Randomized Complete Block Design (RCBD) for field experiments, followed by Analysis of Variance (ANOVA), correlation analysis using SPSS, and path coefficient analysis to determine the contribution of yield-attributing traits.
What content is covered in the main body of the work?
The main body covers the materials and experimental design, detailed results on the performance of the genotypes, and a discussion on how these findings reflect existing scientific literature and the effectiveness of selecting specific traits for breeding.
Which keywords best characterize this study?
Key terms include Maize, Genotypes, Path coefficient analysis, Correlation, Yield components, Variability, and Breeding.
Which genotypes were identified as the most promising?
The study identified ZM-627 (4984 kg/ha) and Across 9942/Across 9944 (4523 kg/ha) as the most promising genotypes based on their grain yield performance.
How does the anthesis-silking interval impact the results?
The study observed that the anthesis-silking interval (ASI) recorded a high positive direct effect on grain yield, suggesting it is a significant factor to be considered alongside other morphological attributes during selection.
- Citar trabajo
- Bishnu Prasad Kandel (Autor), Bijay Kumar Sharma (Autor), Subarna Sharma (Autor), 2019, Varietal Screening of Winter Maize Genotypes in Terai Region of Nepal, Múnich, GRIN Verlag, https://www.grin.com/document/463903
