Principles of Horticulture production 102 (APM) - Practical Sections PDF

Pomology department Principles of Horticulture production 102 (APM) – Practical sections Section 2 – Nurseries and sexual propagation Nursery A nursery is a managed site, designed to produce seedlings grown under favorable conditions until they are ready for planting in the permanent pl...

Pomology department Principles of Horticulture production 102 (APM) – Practical sections Section 2 – Nurseries and sexual propagation Nursery A nursery is a managed site, designed to produce seedlings grown under favorable conditions until they are ready for planting in the permanent place. Components of a good nursery The nursery site should be located in the nutrient rich/medium soil, near to water source, free from soil pathogens and insects. availability of cheap and skilled labors and has good access to the main road for easy transportation. Plant propagation structures A greenhouse is a framed, infrastructure covered with a transparent material in which crops can be grown under at least partially controlled environment. Various designs of greenhouse viz., shade net house, plastic film green house, glass house and natural green houses may be designed according to the need and resource availability. Growth media Sand Clay Peat moss  Sexual propagation Sexual propagation in plants involves seeds or spores and takes advantage of meiosis and recombination of genetic material. In this case, resulting offspring contains genetic material from both male and female parents. Sexual propagation starts when compatible pollen is sprayed/ dropped on the flower’s stigma, which fertilizes the egg in the ovary by growing down through style of the carpel. The embryo formed by the union of pollen and an egg develops into a seed which is often contained in a fruit or similar structure. Advantages of Sexual Plant Propagation It is the easiest and least expensive method of plant propagation. Seedling trees are harder and have longer life span. Plants which are difficult to propagate by vegetative method e.g. papaya,. can only be propagated by seed. The rootstocks for budding and grafting are obtained by means of sexual propagation. Sexually propagated plants are more resistant to pests and disease. Polyembryonic varieties (give rise to more than one seedling from one seed) can be propagated by seed. Disadvantages of Sexual Plant Propagation Seedlings take more time to bear fruits (late bearing) Quality of existing plants cannot be improved by sexual propagation Plants propagated sexually are large in size, thus the cost of manuring, pruning and spraying increases Due to cross pollination and segregation, there is no assurance about genetic purity of plant. Identification of sex in seedling is difficult.