Rosidae I

1
Rosidae I

• Rosales - Santalales

2
Characteristics of Rosidae

• largest subclass of flowering plants with 18
  orders, 114 families, and ca. 58000 species (over
  1/3 of the dicot families)
• almost 75 of the species are classified in five
  orders Fabales, Euphorbiales, Myrtales, Rosales
  and Sapindales
• basal members are comparable to the primitive
  Magnoliidae while most advanced share features
  with members of the Asteridae

3

• members of the Rosidae tend to have perigynous or
  epigynous flowers
• those with hypogynous flowers usually bear a
  characteristic fleshy nectar ring associated with
  ovary
• members of the Rosidae occur in nearly all
  terrestrial ecosystems
• primitive orders with apocarpous gynoecia, orders
  primarily adapted to an aquatic, hemiparasitic,
  or parasitic existence (Rosidae I)

4
Orders of the Rosidae

• Rosales
• Fabales
• Proteales
• Podostemales
• Haloragales
• Myrtales
• Rhizophorales
• Cornales
• Santalales

• Rafflesiales
• Celastrales
• Euphorbiales
• Rhamnales
• Linales
• Polygalales
• Sapindales
• Geraniales
• Apiales

5
Crassulaceae

• family of succulent herbs and small shrubs
• Distribution distributed throughout the world,
  mainly in warm, dry regions but centered in South
  Africa
• like the other two succulent families (Aizoaceae
  and Cactaceae), they are found in hot, exposed,
  rocky habitats

6

• Crassulaceae have a wider range of adaptability
  species of Sempervirum and some of Sedum are
  frost-hardy and some species of Crassula and
  Sedum live in plentiful water supply, one
  Crassula (C. helmsii) being aquatic

7
Diagnostic Features

• perennial plants, soft-wooded and rarely larger
  than small shrublets
• Lvs. always /- fleshy and mostly entire,
  exstipulate and commonly packed tightly in
  rosettes which may reach the extreme of surface
  reduction in a sphere in Crassula columnaris
• full range of xerophytic specializations
  surfaces covered in papillae, hairs, bristles or
  wax

8
Crassula columnaris
9

• vegetative reproduction from offsets,
  adventitious buds and fallen leaves is common
• Flws. small but massed in showy corymbs or
  panicles, structurally simple
• Perianth normally five (3-30) free sepals and
  petals
• Androecium one or two whorls of stamens, equal
  to the number of petals

10

• Gynoecium ovary superior, unilocular
• Fruit cluster of follicles

11
Classification

• Division Magnoliophyta
• Class Magnoliopsida
• Subclass Rosidae
• Order Rosales
• Family Crassulaceae

12
Classification

• consists of about 35 genera and 1500 species
• divided in to two groups
• stamens as many as petals and lvs. opp. (Crassula
  and Rochea)
• stamens twice as many as petals and lvs. alt. or
  opp. (Kalanchoe, Sedum, Sempervirum)
• closely related to the non-succulent
  Saxifragaceae

13
Economic Uses

• valued mainly as ornamentals
• stonecrops (Sedum) for rock gardens
• houseleeks (Sempervirum) for alpine gardens
• Echeveria for summer bedding
• Kalanchoe and Rochea as house plants and
  florists flowers

14
Saxifragaceae (sensu stricto)

• large and widespread family consisting mainly of
  perennial herbs
• in the broad sense, Saxifragaceae consists of
  gooseberries and currants as well as popular
  garden flowers like hydrangeas and saxifrages
• Distribution on its wide interpretation, the
  family is almost cosmopolitan majority of the
  species are found in the north temperate zone
  with representation in the tropics, South Africa,
  Australia, and New Zealand scanty

15
Diagnostic Features

• Lvs. alt. opp. or all basal, simple,
  exstipulate
• Infl. terminal panicles or racemes
• Flws. perfect, actinomorphic, with hypanthium
• Perianth sepals 5, connate, petals 5, distinct
• Androecium stamens 5-10, distinct
• Gynoecium 2, distinct to connate, ovary
  superior or inferior
• Fruit capsule or cluster of follicles

16
Classification

• Division Magnoliophyta
• Class Magnoliopsida
• Subclass Rosidae
• Order Rosales
• Family Saxifragaceae

17
Classification

• consists of ca. 40 genera and 650 species with 22
  genera and 165 species in North America north of
  Mexico
• classification of Saxifragaceae is extremely
  controversial
• woody genera often included in the Saxifragaceae
  (sensu lato) are now included in other families
  like the Grossulariaceae
• the genus Penthorum often included in the
  Crassulaceae or its own family, the Penthoraceae
  is anomalous

18
Classification

• Saxifragaceae (sensu stricto) is divided into 2
  subfamilies
• Parnassioidae (staminodes present, flws.
  solitary, styles/stigmas appressed to fused,
  capsules loculicidal)
• Saxifragoideae (staminodes absent, flws. 2 or
  more, styles/stigmas mostly free, capsules
  septicidal or circumcissle)

19
Economic Importance

• Saxifragaceae (sensu lato) consists of the genus
  Ribes (Grossulariaceae) which has gooseberries,
  black, red, and white currants which are widely
  grown for their edible fruits
• many other genera such as Tolmeia, Tiarella,
  Saxifraga, and Heuchera are grown as garden
  ornamentals