Rice Nursery and Early Crop Management

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Presentation transcript:

Rice Nursery and Early Crop Management V. Balasubramanian IRRI

IRRI: Rice Production Course Learning Objectives Describe different types of rice nursery management Describe the critical factors of the rice transplanting process Describe the advantages and constraints of manual transplanting and seedling broadcasting Describe preparation and leveling of fields for direct seeding IRRI: Rice Production Course

What is the goal of Crop Establishment?  To secure a uniform plant population that can produce high yields IRRI: Rice Production Course

Target panicles for high yield Number of panicles per unit area is the principal yield-determining factor Optimum number of panicles per unit area: Wet season: 350-400 panicles m-2 Dry season: 450-600 panicles m-2 Factors affecting number of panicles: Tillering capacity of the variety Initial plant population (based on CE method) Available N level at tillering IRRI: Rice Production Course

Most common method in small farms of Asia Transplanting: Most common method in small farms of Asia

Types of Rice Nursery Wet-bed Dry-bed Dapog (Mat) Modified mat Bubble Tray

IRRI: Rice Production Course Wet-bed Nursery-1 Compute the seed & seedbed area: 50 kg seed & 500 m2 seedbed area for TP one ha of main field Locate the seedbed away from electric light in a fertile field that is easy to irrigate & drain Start preparing the seedbed 2 weeks before planting time IRRI: Rice Production Course

IRRI: Rice Production Course Wet-bed Nursery-2 Add organic manures and/or fertilizers as needed Irrigate, plow, puddle and level the field Prepare beds of 1 to 1.5 m width, 4-5 cm height & any convenient length Pre-germinate the seeds 2 days before sowing: 24 h soaking & 24 h incubation Sow the pre-germinated seeds on beds IRRI: Rice Production Course

IRRI: Rice Production Course Wet-bed Nursery-3 Water the seedbed 2-3 DAS and then maintain a water level of 2-5 cm, depending on the height of seedlings Apply 20-40 g urea or DAP per m2 at 10 DAS, if needed Apply pesticide only when needed Seedlings are ready for TP from 20-25 DAS IRRI: Rice Production Course

Wet-bed Rice Nursery, Sri Lanka

Wet-Bed Rice Nursery: Cold Injury

Covering nursery bed in cold climate

Does anyone have questions or comments about wet nurseries? IRRI: Rice Production Course

IRRI: Rice Production Course Dry-bed Nursery-1 Compute the seed & seedbed area: 50 kg seed & 500 m2 seedbed area for TP one ha of main field Locate the seedbed away from electric light in a fertile field with light soil and easy access to a water source Start preparing the seedbed 2 weeks before planting time Add enough organic manures &/or fertilizers IRRI: Rice Production Course

IRRI: Rice Production Course Dry-bed Nursery-2 Plow and harrow the field Prepare raised seedbeds of 1.5 m width, 0.1-0.15 m height, and any convenient length Seed priming: weigh required quantity of clean seed, soak for 24 h and then dry in the shade Primed seed is reported to germinate faster than fresh dry seed Sow the primed seeds on raised beds & cover the seed lightly with soil or rice hull IRRI: Rice Production Course

IRRI: Rice Production Course Dry-bed Nursery-3 Water the seedbed till saturation after sowing Then water the bed periodically as seedlings emerge & grow Regulate the water supply, if necessary, to control the rate of seedling growth Apply pesticides to control pests, if needed Seedling are ready from 25-30 DAS IRRI: Rice Production Course

Dry-bed Rice Nursery

IRRI: Rice Production Course Dapog (Mat) Nursery-1 Less labor need Shorter period of raising seedlings Easy transport of seedling-mats to main field Preferred for mechanical transplanting IRRI: Rice Production Course

IRRI: Rice Production Course Dapog (Mat) Nursery-2 Select a level area near the household and/or a water source Mark out 1 m wide and 10 to 20 m long plots Spread a plastic sheet or banana leaves on the marked area Form the boundary with bamboo splits or banana sheath IRRI: Rice Production Course

IRRI: Rice Production Course Dapog (Mat) Nursery-3 Spread the pre-germinated seeds at the rate of 1 kg per 1.5 m2 area 40-50 kg seed sown in 60-75 m2 area is enough to plant one ha of main field Sprinkle water immediately after sowing and then as and when needed IRRI: Rice Production Course

IRRI: Rice Production Course Dapog or Mat Nursery-4 Protect the mat nursery from heavy rains for the first 5 DAS Seedlings will be ready for sowing in 8 to 15 DAS Roll out the seedling mats and transport them to the mail field IRRI: Rice Production Course

Dapog Nursery

Dapog Nursery: Seedling mat

Modified mat nursery-1: Why? Reduced nursery area: 100 m2 to plant 1 ha Establishing seedlings in a 4-cm layer of soil mix, arranged on a firm surface Robust, young seedlings (18-20 cm tall with 4 leaves) produced within 15 DAS Easy transportation of seedling-mats to main field Easy separation of seedlings for transplanting (minimum root damage) IRRI: Rice Production Course

Modified Mat Nursery-2: Preparing Soil Mix Soil : 70-80% Decomposed manure : 15-20% Rice husk : 5-10% Powdered DAP : 1.5 kg/100 m2 **4 m3 soil mix for 100 m2 nursery area IRRI: Rice Production Course

Soil + Manure + Fertilizer Mixture IRRI: Rice Production Course

Manure must be well decomposed, otherwise young seedlings suffer IRRI: Rice Production Course

ICM: Modified Mat Nursery-3 Prepare 100 m2 nursery area to plant 1 ha. Select a level area near the household and/or a water source Mark out 1 m wide and 10 to 20 m long plots Spread a plastic sheet or banana leaves on the marked area Place a wooden frame with 4-cm deep and convenient size segments Fill the frame with soil mixture IRRI: Rice Production Course

IRRI: Rice Production Course Frame for Filling Soil IRRI: Rice Production Course

Filling Soil Mix in Frames IRRI: Rice Production Course

ICM: Modified Mat Nursery-4 Seed: To plant 1 ha, use quality seed @ 9-12 kg seed (for 20 x 20 cm spacing at 1 seedling per hill) 18-25 kg seed (for 20 x 20 cm spacing at 2 seedling per hill) Sow pre-germinated seeds at the rate of 100 to 150 g per m2 area and cover the seed with dry soil and press it gently IRRI: Rice Production Course

Sowing Pre-germinated Seeds IRRI: Rice Production Course

IRRI: Rice Production Course After Sowing Seeds IRRI: Rice Production Course

Covering Seeds with Soil IRRI: Rice Production Course

ICM: Modified Mat Nursery-5 Sprinkle water immediately to soak the bed Then water the bed as and when needed to keep it moist all the time Protect the nursery from heavy rains for the first 5 DAS Continue watering until 15 DAS If the nursery can be flooded, flood the nursery area with 1 cm water level all around at 6-7 DAS IRRI: Rice Production Course

Sprinkling water to soak the bed IRRI: Rice Production Course

IRRI: Rice Production Course Lifting the Frame IRRI: Rice Production Course

Mat Nursery after Sowing IRRI: Rice Production Course

Watering Mat Nursery to Keep It Moist IRRI: Rice Production Course

IRRI: Rice Production Course Seedlings at 5 DAS IRRI: Rice Production Course

Aerobic or Flooded Nursery Beds MMN: Aerobic MMN: Flooded IRRI: Rice Production Course

Flood the nursery area with 1 cm water level at 6-7 DAS IRRI: Rice Production Course

ICM: Modified Mat Nursery-6 Optional: Sprinkle 0.5% urea solution at 9 DAS, if seedling growth is slow or leaves are yellowing (1.5 kg urea/300 l for 100 m2 area) Seedlings reach 18-20 cm tall at 15 DAS If flooded, drain the water 2 days before lifting the seedling-mats Lift & transport the seedling-mats to mail field Separate the seedlings and transplant them at 1-2 per hill at 20x20 to 25x25 cm spacing IRRI: Rice Production Course

Sprinkling 0.5% urea solution at 9 DAS IRRI: Rice Production Course

IRRI: Rice Production Course Seedlings at 15 DAS IRRI: Rice Production Course

Lifting the Seedling Mats IRRI: Rice Production Course

IRRI: Rice Production Course Seedling Mats at 15 DAS IRRI: Rice Production Course

Does anyone have questions or comments about mat nurseries? IRRI: Rice Production Course

Seedling Broadcasting (SB) 12-15-d old seedlings with root balls Seedlings raised on plastic trays Size: 59 cm x 34 cm with 434 embedded holes 750 trays ha-1 Seed bed area: 250 m2 to plant one ha Nursery in uplands, lowlands or near the house In lowlands, 75 cm wide and 9-12 cm high seed beds are used Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

IRRI: Rice Production Course A Plastic Bubble Tray IRRI: Rice Production Course Source: Dr. Sumith, RRDI, SL

Bubble Tray Nursery Preparation (250 m2 to plant 1 ha) Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

Bubble Tray Nursery: Seeding (Seed rate: 15-20 kg ha-1) Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

Bubble Tray Nursery: Seedlings with root balls Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

Does anyone have questions or comments about bubble tray nurseries? IRRI: Rice Production Course

Rice Nursery Types: Summary To plant 1 ha of main field Optimum seedling age, d Nursery area, m2 Seed rate, kg ha-1 Wet-bed 400-500 50 20-25 Dry-bed 500 25-30 Dapog (mat) 60-75 40-50 8-15 Modified mat 100 9-25 15 Bubble tray 250 15-20 12-15 IRRI: Rice Production Course

Transplanting: Critical Factors Proper nursery management Careful handling of young seedlings for fast revival and early growth after TP Shallow transplanting at 1-2 cm depth Optimum plant-to-plant spacing: 20 x 20 cm to 25 x 25 cm Optimum number of seedlings: 1-2 hill-1 IRRI: Rice Production Course

Effect of plant spacing & seedling number per hill on initial plant count and required tillers per plant

Modified Mat Nursery: Young Seedlings 16-18 cm tall 4 leaves No tillers IRRI: Rice Production Course

TP: Careful Handling of Seedlings IRRI: Rice Production Course

Square Planting (with 1-2 seedlings per hill) IRRI: Rice Production Course

Mechanical Weeding + Soil Disturbance Incorporates weeds at < 4-leaf stage Better root & shoot growth High tillering IRRI: Rice Production Course

IRRI: Rice Production Course ICM Crop at Heading IRRI: Rice Production Course

Manual Transplanting: what are the advantages? Good head start for plant growth over weeds Shorter duration in main field Easy to maintain uniform plant spacing & population, if planted in rows

Manual TP: What are the constraints?  Tedious & labor intensive, > 30 PD ha-1  Drudgery & back problem  Difficult to find labor to plant on time  Poor plant population due to contract TP on area basis

IRRI: Rice Production Course IRRI Manual Planter IRRI: Rice Production Course

 Chinese planter  Japanese planter

IRRI: Rice Production Course Seedling Broadcasting Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

Seedling Broadcasting-Manual IRRI: Rice Production Course Source: Dr. Sumith, RRDI, SL

IRRI: Rice Production Course Seedling Broadcasting by Machine IRRI: Rice Production Course

Seedling Broadcasting: What are the advantages Low seed rate: 15-20 kg ha-1 Less labor for CE (16 for SB vs. 30-36 for TP) No bird damage in the nursery and main field Early crop maturity by 7-8 days Water saving: 10 irrigations for SBR vs. 12 for TPR Less use of agro-chemicals as they can be applied directly to the nursery Source: Dr. Sumith, RRDI, SL IRRI: Rice Production Course

Seedling Broadcasting: What are the limitations? Farmers have to buy plastic trays Heavy rains just after SB may disturb the distribution of broadcasted seedlings IRRI: Rice Production Course

SB: On-station Yield Trials Stand Establishment Method Season 2002/03 Wet 2003 Dry Mean ------- Grain Yield (t/ha)------- Manual transplanting 6.09 5.66 5.87 Seedling b/casting (SB) 6.06 5.28 5.67 6.07 5.47 IRRI: Rice Production Course

IRRI: Rice Production Course On-farm Yield Trials Characteristic Site Weera Pedasa Jayanthipura Average SB TP No. of hills m-2 38 42 49 39 44 41 No. of panicles m-2 321 293 391 302 356 298 Grain yield (t ha-1) 8.8 8.5 9.0 8.9 IRRI: Rice Production Course

TP: Labor Need and Machine Costs CE method Nursery type Labor need (person-days ha-1) Machine cost (US$) Nursery Planting Total TP-manual Wet/Dry bed 12 25-30 37-42 -- Dapog (mat) 6 31-36 Modified mat 8 33-38 Seedling Broadcast Bubble tray 16 TP-machine (Dapog or seedling trays) IRRI: Walk on 6-7 12-13 600 Chinese 2-3 8-9 2,750 Japanese 1 7 15,000 IRRI: Rice Production Course

Direct Seeding of Rice: Why? To reduce labor input & drudgery To tackle labor shortage & high wages To establish crops on time To maintain optimum plant population IRRI: Rice Production Course

Direct Seeding of Rice: Incentives Availability of S.D. rice varieties Availability of cost-efficient, selective herbicides Faster and easier crop establishment IRRI: Rice Production Course

Direct Seeding Requirements Good LP & leveling Furrows to drain water (WDS) Saturated soil (WDS) & moist soil (DDS) for first 7-10 days Varieties: early seedling vigor, fast canopy dev., non-lodging Quality seed Effective weed control: cultural, mechanical, herbicides IRRI: Rice Production Course

Well-prepared and Leveled Fields for Direct Seeding Level field for DDS Level field for WDS

Direct Seeding: Benefits Faster and easier crop establishment Less labor need (1-2 vs. 25-30 for TP) Earlier crop maturity by 7-10 days More efficient water use & higher tolerance to water stress Reduced cost: US$ 60-80 per ha Less methane emission: DDS < WDS < TP IRRI: Rice Production Course

Direct Seeding Methods Wet direct seeding (WDS): puddled soil, broadcast- or row-seeded Surface WDS Subsurface WDS Water seeding Dry direct seeding (DDS): dry/moist soil, broadcast or drilled in rows IRRI: Rice Production Course

IRRI: Rice Production Course WDS: Broadcasting Most common wet seeding method Sprouted seeds Seed rate: 80-250 kg ha-1 IRRI: Rice Production Course

WDS: Drum Seeding in Rows  Sprouted seed Seed rate: 60-80 kg ha-1 Better plant stand    IRRI: Rice Production Course

IRRI: Rice Production Course Drum seeder, Vietnam 8 kg wt + 12 kg seed IRRI: Rice Production Course

Seed hoppers Seed holes Drum seeder

Dry Seeding Dry broadcasting Seeding behind plow Machine seeding Used in rainfed areas Dry seed Seed rate 300 kg ha-1 Germination with rainfall; drought High pest incidence Dry broadcasting Seeding behind plow Machine seeding

Zero-till drill and planting

Bed Planting

TPR-B: Transplanting seedlings on bed Good CE, but more labor Good plant growth & uniform tillering Less water use (by 20-30%) than that of TPR High yield as that of TPR IRRI: Rice Production Course

DSR-B: Dry drill seeding on beds Fast & efficient seeding, but poor CE May need saturated soil for the first 25-30 days Conserves rain water & avoids flooding Saving in water (~ 20-30%) Micro-nutrient deficiency: Fe, Zn, Cu, etc. Severe weed infestation, needs effective herbicides Termite problems

Can anyone briefly explain: Seedling broadcasting? Direct seeding? IRRI: Rice Production Course

T h a n k y o u

IRRI: Rice Production Course Rice Nursery: Some Calculations-1 1. What is the area per ha? 100m x 100m = 10,000 m2 2. How many hills per ha ? (at 20 x 20 cm spacing) 10,000 / (0.2 x 0.2) = 250,000 hills per ha 3. How many seedlings per ha? (at 4 per hill) 250,000 x 4 = 1,000,000 IRRI: Rice Production Course

IRRI: Rice Production Course Rice Nursery: Some Calculations-2 4. How many seeds you need per ha? 1,000,000 seeds per ha 5. What is the weight of 1000 seeds? Range: 20-30 g Mean : 25 g 6. How much seed you need to plant one ha? (1,000,000/1000) x (25/1000) = 25 kg IRRI: Rice Production Course

IRRI: Rice Production Course Rice Nursery: Some Calculations-3 7. What is the % germination for rice seed? Range: 50 to 90% Mean : 70% 8. At 70% germination, how much seed you need per ha? Seed: 25/0.7 = 36 kg 9. What % of seedlings survive in wet-bed nursery Range: 50-90% Mean : 70% 10. Finally how much seed you need for wet-bed nursery to plant one ha? Seed rate: 25/(0.7 x 0.7) = 51 kg per ha IRRI: Rice Production Course

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