Growth Stages of the Rice Plant Part 1: Understanding the PalayCheck System

We can observe the changes in their growth stages. 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

Stage 4 Panicle initiation to booting 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

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 7 Milk grain

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

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

ACKNOWLEDGMENT: IRRI, PhilRice

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

Which do you think are the stages where plants need water? Germination to emergence Seedling stage Tillering Stem elongation Panicle initiation to booting Heading Flowering Milk grain Dough grain Mature grain You may do this as a group activity. Ask participants to defend their answers. If it is a group activity, ask a representative to report and defend their answers.

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

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

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

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

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

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

Stage 6 Management Considerations: Flowering -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 Management Considerations: Milk grain -manage rice bug; rice bug is destructive at this stage

Stage 8 Dough grain Management Considerations: - drain water

Stage 9 Management Consideration: Mature grain - 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? Germination to emergence Seedling stage Tillering Stem elongation Panicle initiation to booting Heading Flowering Milk grain Dough grain Mature grain But not so much; too much can reduce tillering.

CREDITS Mr. Alfred Real Note: 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 PhilRice staffers. Produced in 2011. Text: 0920-911-1398