Growth Stages of the Rice Plant Part 1

Growth Stages of the Rice Plant Part 1: Understanding the Palay. Check System

We can’t talk to our plants, or even ask them. So how do we know what they need and when they need them? Hey, how are you? We can observe the changes in their growth stages.

For example

Stages in the VEGETATIVE PHASE

Stage 0 Germination to emergence • Embryo starts to germinate • Variety, temperature, water and air affects growth • End of stage 0: 3 DAS first leaf appears

Stage 1 Seedling • Leaves continue to develop at the rate of 1 every 3 -4 days during the early stage. • Secondary adventitious roots replace the temporary radicle. • 20 to 25 -day-old seedling ready for transplanting.

Stage 2 Tillering • Tillers displace a leaf as they grow and develop • Extends from first tiller to maximum tillering • At maximum tiller stage, some tillers die or level off

Stage 3 Stem elongation • Begins before panicle initiation in late-maturing varieties • In short-duration varieties, stem elongation and panicle initation occur simultaneously.

Stages in the REPRODUCTIVE STAGE

Panicle at 7 -10 days after initiation Stage 4 Panicle initiation to booting • Begins with panicle primordium initiation at the tip of growing shoot • End of stage 4: young panicle is about to emerge • Spikelets become distinct. ‘Pagbubuntis’ You may get a shoot and open it, showing the spikelets, to know if seedling is at booting stage (nagbubuntis)

Stage 5 Heading • ‘Head’ of the grain shows up • 50% of the panicles have exerted • Usually takes 10 -14 days for all plants to complete heading

Stage 6 Flowering • • ‘Anthesis’-- flowering At flowering, the florets open, anthers protrude, pollen is shed florets then close Occurs about 25 days after visual panicle initiation Plant is most sensitive to stress

Stages in the RIPENING STAGE

Stage 7 Milk grain § The grain starts to fill with a white milky liquid that can be squeezed out. § The top of the panicle bends gently in an arc. § The panicle and the 3 uppermost leaves are green

Stage 8 Dough grain • Noticeable changes: yellow spikelets remaining leaves dry up scenescence

Stage 9 Mature grain Grains are fully developed, mature, golden yellow, and hard • Most of the upper leaves are dry and the panicles bent down •

ACKNOWLEDGMENT: IRRI, Phil. Rice

This farmer, Manong Fred… At which stage/s do my plants need water?

Which do you think are the stages where plants need water? q Germination to emergence q Heading q Seedling stage q Flowering q Tillering q Milk grain q Stem elongation q Dough grain q Panicle initiation to booting q Mature grain

Stage 0 Germination to emergence Management Considerations: Water • Waking the seed • Metabolic activities • Translocation of food • Proper soaking of seeds Air • Respiration • Limited oxygen in water • Slow growth • Weak seedlings Temperature • Hasten activities • Above 40 C no germination • Below 10 C no germination • IDEAL 30 C

Stage 1 Seedling Management Considerations: Care of seedlings in the seedbed • Sufficient water • Fertilizer application at 10 DAS Seedling pulling • Avoid stress Transplanting • Minimize transplanting shock

Stage 2 Tillering Management Considerations: Water management • 3 -5 cm water depth Nutrient management • Sufficient P-fertilizer (early tillering) • Sufficient N-fertilizer (mid-tillering) Weed management

Stage 3 Stem elongation Management Considerations: - Variety selection - Time of planting

Stage 4 Panicle initiation to booting Management Considerations: - sufficient K-fertilizer - 5 -7 cm water depth THINK: Drinking too much water will be bad for you; drinking less than what you need will be too.

Stage 5 Heading Management Considerations: -manage drought, it will cause significant yield -protect plants from diseases, especially Blast

Stage 6 Flowering Management Considerations: -manage drought -temperature -strong wind and rain What do you think happens when there is not enough water at this stage? Basic science tells us that water is essential in growth. Water will be essential for grain filling.

Stage 7 Milk grain Management Considerations: -manage rice bug; rice bug is destructive at this stage

Stage 8 Dough grain Management Considerations: - drain water

Stage 9 Mature grain Management Consideration: - harvest at 80 -100% grain maturity or when most of the grains are golden yellow

Which do you think are the stages where plants need water? q Germination to emergence q Heading q Seedling stage q Flowering q Tillering q Milk grain q Stem elongation q Dough grain q Panicle initiation to booting q Mature grain But not so much; too much can reduce tillering.

CREDITS Instructional presentation designer: Ms. Ella Lois T. Bestil and Mr. Alfred Real Sources of technical content/reviewers of presentation: Mr. Alfred Real Note: Adapted from a powerpoint presentation developed by: Mr. Alfred Real You may use, remix, tweak, For more information, visit: & build upon this presentation non-commercially. However, always use with acknowledgment. Unless otherwise stated, the names listed are Phil. Rice staffers. Produced in 2011. Text: 0920 -911 -1398