chapter 12 Senescence Physiology
chapter 12 Senescence Physiology
复习: Chapter 5: Plant reproductive physiology Induction Signal Competent: Expressed Able to respond in Able to follow same expected manner developmental The apical meristem when given the Photoperiod program even after Hormones? undergoes ppropriate removal from its normal position in morphogenesis developmental Vegetative growth Flowers Chapter 6: Plant maturation and senescence a Fertilized nucleus (3n) Quiescent Developing egg (2n)
Chapter 5:Plant reproductive physiology Chapter 6:Plant maturation and senescence 复习:
Plant maturation and senescence Obiectives of this chapter. Formation of fruit and seed(Parthenocarpy Physiological changes during seed and fruit development (conversion of organic compound,, respiration climacteric) >Understand the concept and categories of dormancy General types of plant senescence > The physiological and biochemical changes during senescence >Mechanism of plant senescence > Environmental influences on senescence
Plant maturation and senescence Objectives of this chapter: ➢Formation of fruit and seed (Parthenocarpy) ➢Physiological changes during seed and fruit development (conversion of organic compound,, respiration climacteric) ➢Understand the concept and categories of dormancy ➢General types of plant senescence ➢The physiological and biochemical changes during senescence ➢Mechanism of plant senescence ➢Environmental influences on senescence
Plant maturation and senescence Objectives of this chapter: Formation of fruit and seed Physiological changes during seed and fruit development(conversion of organic compound, Parthenocarpy, respiration climacteric) >Understand the concept, categories, causes of dormancy General types of plant senescence The physiological and biochemical changes during senescence Mechanism of plant senescence >Environmental influences on senescence
Plant maturation and senescence Objectives of this chapter: ➢Formation of fruit and seed ➢Physiological changes during seed and fruit development (conversion of organic compound, Parthenocarpy, respiration climacteric) ➢Understand the concept, categories, causes of dormancy ➢General types of plant senescence ➢The physiological and biochemical changes during senescence ➢Mechanism of plant senescence ➢Environmental influences on senescence
Origin of fruit and seed Pollination Stigma柱头 Ovule develops to seed Style The fertilized egg(zygote) grows Pollen tube into the embryo(2n) Ovule Oary子房 The fertilized endosperm nucleus 胚珠 eD+ Integument珠被 forms the nutritive endosperm(3n) The integument forms the seed coat E (testa)(2n) Fertilization Female Fertilized gametophyte nucleus (n) Cotyledons Ax Fertilized Embryogenesis
Ovule 珠被 子房 柱头 胚珠 Ovule develops to seed The fertilized egg (zygote) grows into the embryo (2n) The fertilized endosperm nucleus forms the nutritive endosperm (3n) The integument forms the seed coat (testa) (2n) Origin of fruit and seed
Fruit formation Pollination The ovary(2n) tissues usually form the fruit(strawberry is an exception igma the receptacle花托 swells) Ovary Pollen tube Integument Hormones(e.g auxins) released from the seed control fruit growth. When ertilization seeds are removed, fruit growth is affected Female mesophyte m
Ovary ▪ Hormones (e.g. auxins) released from the seed control fruit growth. When seeds are removed, fruit growth is affected ▪ The ovary (2n) tissues usually form the fruit (strawberry is an exception: the receptacle花托 swells) Fruit formation
Parthenocarpy(单性结实) The formation of fruits without fertilization and seed production Examples: seedless grapes ,, nave oranges Two types of parthenocarpy 1. Caused by the flow of plant hormones to the ovary from the parent plant 2. Achieved commercially for some species by spraying IAA) Thompson seedless grape
▪ The formation of fruits without fertilization and seed production ▪ Examples: seedless grapes,, navel oranges ▪ Two types of parthenocarpy 1.Caused by the flow of plant hormones to the ovary from the parent plant 2. Achieved commercially for some species by spraying IAA) Thompson seedless grape Parthenocarpy （单性结实）
Plant maturation and senescence Objectives of this chapter: >Origin of fruit and seed Physiological changes during seed and fruit development >Understand the concept and categories of dormancy >General types of plant senescence The physiological and biochemical changes during senescence > Mechanism of plant senescence >Environmental influences on senescence
Plant maturation and senescence Objectives of this chapter: ➢Origin of fruit and seed ➢Physiological changes during seed and fruit development ➢Understand the concept and categories of dormancy ➢General types of plant senescence ➢The physiological and biochemical changes during senescence ➢Mechanism of plant senescence ➢Environmental influences on senescence
Physiological changes during seed 1. Reserve deposition 2. Increased respiration (to provide energy for reserve synthesis). 3. Hormones increase in the turn of: cytokinin, gibberellin and auxin, ABa Fertilized endosperm nucleus (3n) Cotyledon As⑧ Quiescent Developing Fertilized embo egg (2n) Embryo
1.Reserve deposition 2. Increased respiration (to provide energy for reserve synthesis). 3. Hormones increase in the turn of: cytokinin, gibberellin and auxin, ABA Physiological changes during seed development
1. Reserve deposition 2. Increased respiration(to provide energy for reserve synthesis). 3. Hormones increase in the turn of: cytokinin, gibberellin and auxin. ABa Soybean(大豆) protein amino acids A Wheat(小麦) starch sucrose(glucose, fructose Canola(油菜) lipidsucrose (glucose, fructose? During seed maturation, Proteins or starches or lipids(based on the seed types) are synthesized using soluble carbohydrates, amino acids from their parent plants
? Soybean（大豆）protein amino acids Wheat （小麦）starch sucrose (glucose, fructose) During seed maturation, Proteins or starches or lipids (based on the seed types) are synthesized using soluble carbohydrates, amino acids from their parent plants. Canola （油菜）lipid sucrose (glucose, fructose) 1.Reserve deposition 2. Increased respiration (to provide energy for reserve synthesis). 3. Hormones increase in the turn of: cytokinin, gibberellin and auxin, ABA