CSISA 1

CEREAL SYSTEMS INITIATIVE FOR SOUTH ASIA (CSISA)

7 June 2011, IRRI Office, Dhaka

Phases and stages of rice plant

3 Phases:1. Vegetative phase2. Reproductive phase3. Ripening phase

Ripening phase-: 30 days,Reproductive phase: 30 daysRest part vegetative phase

Growth phases of rice plant (Varietals differences)

Vegetative Phase100 days

Reproductive Phase

30 days

Ripening Phase

30 days

BRRI dhan29(160 days)

Vegetative Phase80 days

ReproductivePhase

30 days

RipeningPhase

30 days

BRRI dhan28(140 days)

Impact of temperature on growth phases (BR 3)

Vegetative Phase110 days

Reproductive30 days

Ripening30 days

Boro(170 days)

Vegetative Phase70 days

Reproductive30 days

Ripening30 days

Aus(130 days)

Vegetative Phase85 days

Reproductive30 days

Ripening30 days

T. Aman(145 days)

Vegetative phase

Basic vegetative phase: Lag vegetative/ photosensitive phase

• Period of this stage: Generally 35-65 days. However, some varieties it takes 20 days and some other takes 85 days

Photoperiod sensitive rice

PI depends on day length

Takes more time after completing of basic vegetative phase

Example of photosensitivity

Photo insensitive Veg. Rep. Ripen. 13 hrs day

Veg. Rep. Ripen 11 hrs day

Photo insensitive/ photosensitive Veg. Rep Ripen. 13 hrs day

Veg. Rep. Ripen. 11 hrs dayActive

Lag

Stages of Rice1. Germination stage:

Coleorhiza starts before coleoptile

But coleoptile comes out earlier than coleorhiza

Soaking for 24-48 hrs and incubation for 24-72 hrs: germinattion occurs

Seedling stage

Seedling stage: germination to 5 leaf stage

Leaf number and tiller relationship

X leaf -3 (L-3)

1-3 = -2 (no tiller)

2-3 = -1 (no tiller)

3-3 = 0 (no tiller)4-3 = 1 (no probability for tillering as leaf 1 is

not fully expanded)

5-3 = 2 (Tiller from 2 node)

In 200 c, 5 days/leaf In 250 c, 4 days/leaf

Transplanting stage

Transplanting to establishment In T. Aus and T. Aman 5-7 days In Boro 10-15 days 0 day in DSR

Tillering stage

a¡lfl kMe 3u d¡ fl L¤¢n N¡S¡u aMe S¢j d¡e N¡ R i l k¡uz

Stem elongation stage

Not visible up to 9 days1.0 t0 1.5 mm after 10 days

Panicle development

Female organs

Male organs

Pollination

Flowering at different parts of panicle

•

90-100 % paddy hard and yellow colouy

Leaf died

Intercultural operations at different stages of rice life cycle

• Weeding

• Fertilizer

• Irrigation

• Yield is the function of number of panicle, filled spikelet and

mean individual grain weight

CSISA 49