Photosynthesis

• Light absorption occurs in the thylakoid membranes of chloroplasts.
• Seed has a greater effect on longevity than temperature.
• For each one percent (1%) increase in moisture content (MC), the longevity of seed decreases by half (Harrington, 1972).
• This rule applies to seed moisture content between 5% and 13%.
• Above 13% MC, seed storage fungi and increased heating due to respiration cause longevity to decline at a faster rate.
• Plant traits can either be qualitative or quantitative and requires specific and efficient breeding methods.
• Sexually- and asexually-reproduced crops differ in genetic structure and segregates at different generations.
• Several breeding methods are available for germplasm improvement.
• Conventional plant breeding involves the development or improvement of cultivars using conservative tools for manipulating plant genome within the natural genetic boundaries of the species.
• Non-conventional methods of breeding for abiotic tolerance include the use of saline-tolerant lines in somatic variations, F1 anther culture, and Marker-assisted Selection for saltol QTL.
• Abiotic Tolerance refers to the ability of a plant to survive in harsh environmental conditions such as drought, flood, and extreme temperatures.
• Conventional methods of breeding for abiotic tolerance include the Pedigree method, Modified bulk pedigree method, and Backcross method.
• Conventional plant breeding includes four main procedures in manipulating plant genome: selection, hybridization, polyploidy, and induced mutation.
• Non-conventional plant breeding, also known as modern plant breeding, involves the use of biotechnology tools to improve the plants’ genetic make-up.
• The most important methods in non-conventional plant breeding are plant tissue culture, marker-assisted selection/breeding, and genetic engineering/plant genetic transformation.
• Conventional plant breeding methods include selection, mass selection, pureline selection, clonal selection, recurrent selection, backcross method, and hybrid seed technology.
• Non-conventional plant breeding methods include plant tissue culture, marker-assisted selection/breeding, and genetic engineering/plant genetic transformation.
• Conventional plant breeding methods also include polyploid breeding and mutation breeding.
• Salinity Tolerance is the ability of the plant to tolerate salt stress.
• Genetic Engineering, also known as Plant Genetic Transformation, is the direct manipulation of a plant’s genes using biotechnology.
• Marker-Assisted Selection (MAS) involves the use of markers to identify plants with specific traits.
• Insect resistance is the property that enables a plant to avoid, tolerate, or recover from injury by insect populations that would cause greater damage to other plants of the same species under similar environmental conditions.
• Abiotic Tolerance includes traits such as Drought Tolerance, which is the ability of the plants to give good yield under moisture deficit conditions, and Flood Tolerance, which is the ability of the plant to tolerate flooding.
• Biotic Resistance can be monogenic, controlled by one or few major genes, or polygenic, controlled by several minor genes.
• Abiotic Tolerance is based on the activation and regulation of specific stress-related genes, mostly controlled by Quantitative Trait Loci (QTLs).
• Disease resistance is the inherent capacity of the plant to prevent or restrict entry or subsequent activity of pathogenic agent.
• Breeding for Specific Traits involves improving plants for specific agronomic characteristics such as yield, plant height, maturity, etc., which are mostly quantitative traits and are controlled by many genes and environment.
• Non-conventional plant breeding methods also include hybridization-selection methods such as pedigree method, bulk method, and single seed descent method.
• Selection methods in conventional plant breeding include mass selection, pureline selection, clonal selection, recurrent selection, backcross method, and hybrid seed technology.
• Selection methods in non-conventional plant breeding include plant tissue culture, marker-assisted selection/breeding, and genetic engineering/plant genetic transformation.
• Selection methods in conventional plant breeding also include polyploid breeding and mutation breeding.
• Selection methods in non-conventional plant breeding also include hybridization-selection methods such as pedigree method, bulk method, and single seed descent method.
• Backcross Method is a system of breeding in which repeated backcrosses are made to transfer a specific character to a well-adapted variety for which the variety is deficient.
• Single Seed Descent Method is a modified form of bulk method, a breeding procedure with segregating populations of self-pollinated species in which plants are advanced by single seeds from one generation to the next.
• Pedigree method is used in self- and cross-pollinated crops.
• Recurrent selection is an extension of Mass selection.
• The general steps in Hybrid Seed Technology are: develop purelines as parentals, develop a system for pollen control, maintain parental lines, and controlled pollination.
• Recurrent selection is a cyclic selection that is used to improve the frequency of desirable alleles for a character in a breeding population.
• Recurrent selection is used in all crop types.
• Recurrent selection is a general method which involves reselection generation after generation with interbreeding of selects to provide for genetic recombination.