In Partial Fulfillment of the Requirements
In Bi 160 and Bi 160.1
First Semester, AY 2012-2013
A Research Paper
Presented to
Anneke Padolina, Ph.D
Department of Biology
Ateneo de Manila University
Submitted by:
Medina, Kryzka
August 2012
I. Introduction
The life cycle of plants is characterized by the change in ploidy of generations; with diploid generations giving rise to haploid generations and vice versa. The diploid generation, commonly called the sporophyte, produces spores via meiosis. Through mitosis these haploid cells develop into a multicellular gametophyte that can be a separate plant in itself or a part of a plant. The gametophyte gives rise to male and female gametes that in turn produce sperm and egg cells, respectively. In gymnosperms and angiosperms, the haploid generations bring forth seeds through fertilization and subsequent growth and development (Solomon et al. 2008).
A seed is associated with the independence of the sporophyte generation. It is comprised of a young plant embryo, an endosperm, a perisperm, and a testa or seed coat making it physiologically and structurally equipped to propagate a new plant. The main function of seeds is to give rise to new plants; thus allowing the continuity of the generation. The emergence of a plant starts with seed germination. Dormant seeds have low moisture content and minimal metabolic activity; such seeds are called quiescent wherein none of the germination processes is occurring (Bewley and Black 1994, Bewley 1997).
Germination is instigated by the imbibition of water by a quiescent seed and concluded by the initiation of the elongation of the embryonic axis, usually the radicle. (Bewley and Black 1994, Bewley 1997). Seed germination consists of three phases: (1) water imbibition, (2) mitochondrial activity and protein
References: Bewley JD. Seed Germination and Dormancy. The Plant Cell. 1997 July;9:1055-1066. Huo J, Simpson G. Promoting Germination of Freshly Harvested Barley Grain with Alkaline Solutions. J. Inst. Brew. 1994 December;100:421-425. Koger C, Reddy K, Poston D. Factors affecting seed germination, seedling emergence and survival of texasweed (Caperonia palustris). Weed Science. 2004;52:989-995. Lin J, Li X, Zhang Z, Yu X, Gao Z, Wang J, Li Z, Mu C. Salinity-alkalinity tolerance in wheat: Seed germination, early seedling growth, ion relations and solute accumulation. African Jouranal of Agricultural Research. 2012 January 12;7(3):467-474. Perveen A, Naqvi, II, Shah R, Hasnain A. Comparative Germination of Barley Seeds (Hordeum vulgare) Soaked in Alkaline Media and Effects on Starch and Soluble Proteins. JASEM ISSN. 2008 September;12(3):5-9.