Planting Material Selection and Preparation PDF

PLANTING MATERIAL SELECTION AND PREPARATION  Two General Types of Plant Reproduction 1. Sexual Reproduction seed as the primary propagule involves fusion of male and female gametes that are derived either from two different paren...

PLANTING MATERIAL SELECTION AND PREPARATION  Two General Types of Plant Reproduction 1. Sexual Reproduction seed as the primary propagule involves fusion of male and female gametes that are derived either from two different parents or from a single parent Cultivars a group of one or more genotypes which have a combination of characters giving it distinctness, uniformity and stability (DUS) Distinctness - proven to be new and distinct from other already available cultivars Uniformity - related to the level and type of variation which is exhibited (usually phenotypic) between different plants within the cultivar Stability - must remain true to its description when it is reproduced or propagated Types of cultivars Pure-line cultivars Open-pollinated cultivars Hybrid cultivars Clonal cultivars Apomictic cultivars Transgenic cultivars 1. Pure-line cultivars developed for species that are highly self-pollinated Homogeneous and homozygous in genetic structure (attained through a series of self-pollination) often used as parents in the production of other kinds of cultivars have a narrow genetic base ✓ Genetically dissimilar plants constitute heterogenous populations. ✓ Genetically similar plants constitute homogenous populations. 2. Open-pollinated cultivars developed for species that are naturally cross-pollinated genetically heterogeneous and heterozygous have a broad genetic base Types of open-pollinated cultivars: Landraces Composites Synthetics  Landraces developed under a set of farmers’ practices of seed selection and field management adapted to local environments genetically heterogeneous Composite varieties formed by mixing genotypes from several sources with a desired array of characteristics and allowing the genotypes to intermate Synthetic synthesized by crossing a number of genotypes developed by inbreeding (inbred lines) the synthetic variety is maintained by open pollination 3. Hybrid cultivars produced by crossing inbred lines Product of the exploitation of hybrid vigor (or heterosis) to produce superior yields Heterosis - superiority of the progeny over both its parents in terms of yield and some other characters) homogeneous but highly heterozygous more widespread in cross-pollinated species (e.g., corn, sorghum) Types of Hybrids Single-cross formed by crossing two genotypes, usually inbred lines Three-way formed from three inbred lines; a single-cross hybrid formed from two inbred lines is crossed to another (a third) inbred line Double-cross produced from crossing two single-cross hybrids each of which has been produced from two inbred lines. Topcross hybrid produced by crossing an inbred line and an open-pollinating variety 4. Clonal cultivars propagated by using plant parts other than seed (vegetative parts such as stems and roots) plants with identical genotypes (homogeneous) genetically highly heterozygous sexually reproducing but are propagated clonally (vegetatively) by choice (improved through hybridization) clonally propagated hybrid cultivars may be harvested and used for planting the next season without adverse effects 5. Apomictic cultivars Apomixis – phenomenon where seed is produced without the benefit of the union of male and female gametes (i.e., without fertilization) seed harvested genetically identical to the mother plant asexual reproduction via seed agamospermy have the same benefits of clonally propagated ones they have the convenience of vegetative propagation through seed common in perennial forage grasses 6. Transgenic cultivars a cultivar which will produce a plant that contains a gene or genes that have been artificially inserted instead of the plant acquiring the gene or genes through pollination Examples: Corn Soybean Rice Papaya Cotton Breeder, Foundation, Registered and Certified Seeds Breeder seeds (BS) From breeding institutions (IRRI, UPLB, and PhilRice). According to the National Seed Quality Control Services (NSQCS), BS should be 100% pure with no mixture of any other seeds except for inert matter White tag Foundation seeds (FS) From BS that were planted by the different branches of PhilRice and select member of R&D network Certified by NSQCS as 99% pure (unlike BS, FS can have 1-2 seeds from other varieties in every 500g) Red tag  Registered Seeds (RS) Seed multiplication of (RS) is done by certified seed multiplier farmers or farmer’s organization Certified by NSQCS as 98% pure (not more than 5 seeds from weeds, 2% inert matter, 1 seed from red rice in every 500g, and 5 seeds from other varieties in every 500g green tag Certified Seeds (CS) Multiplied by select seed multiplier farmers or farmer’s organization 98% pure (not exceeding to 0.1% seeds from weeds and other plants,2% inert matter, 2 seeds from red rice in every 500g, and 20 seeds from other varieties in every 500g. blue tag Distributed to farmers for commercial production Using good, clean, and healthy seed What is good seed? Obtaining good seed pure (of the chosen variety) full and uniform in size Buy certified seed that is viable (more than 80% pure and labelled germination with good seedling get farmer-produced good vigor) seed, or free of weed seeds, seed-borne select your own good seed diseases, pathogens, insects or other matter Seed should be properly labeled Pre-germination Treatment 1. Seed treatment with fungicides Vegetable and Leguminous Seeds – Captan, Arasan, Spergon, Semesan Corn Seed – apply Metalaxyl to provide protection against downey mildew 2. Seed Inoculation Bio N MykoPlus BioGroe MYKOVAM BioPlasma NitroPlus BioSol-P Oryzinc Maizinc MycoGroe PhosphoLink You may visit https://biotech.uplb.edu.ph/products-and-technologies/ 2. Asexual reproduction Natural Methods include strategies used by the plant to propagate itself Bulb, Corm, Rhizome, Stolon, Tuber Artificial Methods employed to give rise to new, and sometimes novel, plants include grafting, cutting, layering, and micropropagation Natural Asexual Propagation Bulb (modified leaves) - a modified shoot consisting of a very much shortened stem enclosed by fleshy leaves (e.g. Onion) Natural Asexual Propagation Corm (modified stem) - a swollen stem base bearing buds in the axils of scale-like remains of leaves from the previous years growth (e.g. taro) Natural Asexual Propagation Rhizome - an underground stem with buds in the axils of reduced leaves (e.g. ginger) Natural Asexual Propagation Tuber - a swollen stem that grows beneath the soil surface bearing buds (e.g. Potato) Natural Asexual Propagation Stolon - a horizontally growing stem that roots at nodes (e.g. Strawberry) Preparation of Vegetative Plant Material Cassava (mature portion of the stem, at least seven months old, is used and cut into 20-25 cm length) Sugarcane (top portion of the stalk is used; seed pieces called “lalas” should have 3 nodes)  Sweet Potato and Kangkong (vine cuttings 25 to 30 cm long from tip portion are used) Potato (tuber is cut into seedpieces, each having a bud) Recommended Varieties Kindly visit: https://nsic.buplant.da.gov.ph/registry.php