Course : Grain QualityModule 2 : Seed to Seed QualityLesson 1 : How do operations of a farm affect quality?

Transportation

Variety

LandPreparation

W aterM anagem ent

NutrientM anagem ent

W eedM anagem ent

Planting

Harvesting

C leaning

Drying

Storage

SEED TO SEED CYCLE

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 2 : Selection of variety’s affect quality

CONSIDERATIONS: RICE VARIETY SELECTION

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 3 : Three requirements of good crop management

Water Management

To manage water, fields must be level and bunds or levees maintained. Uniform water depth across the field will contribute to:

• a more uniform crop • higher grain yields • consistent moisture content in the grain

Building bunds.

REQUIREMENTS: GOOD CROP MANAGEMENT

Nutrient Management

The right application levels of suitable fertilizers for the variety and growing conditions is essential. Prudent application of nitrogen is essential to get an evenly maturing crop with full grain size and high protein levels.

NOTE: Excessive or uneven application of nitrogen can stimulate late tiller production which results in heads on the main culm ripening a number of days faster than the tillers. This results in more immature and green heads as well as higher moisture content that increases the chance of fissuring and spoilage.

Conversely insufficient nitrogen can lead to reduced grain size and protein content.

Farmers using the Leaf Color Chart (LCC) for determining appropriate Nitrogen application.

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 3 : Three requirements of good crop management

REQUIREMENTS: GOOD CROP MANAGEMENT

Planting

Establishing the correct plant population during planting is essential to maximize:

• Water efficiency • Nutrient efficiency

Appropriate plant density is essential to maximizing a variety's yield potential.

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 3 : Three requirements of good crop management

REQUIREMENTS: GOOD CROP MANAGEMENT

If Then

the plant population is too low,

the yield and quality of the variety can be reduced due to:• increased tillering which increases variation in panicle

maturity. • increased weed populations.

the plant population is too high,

the yield and quality of the variety can be reduced due to:• competition for water and nutrients, resulting in reduced grain

size. • mutual shading resulting in reduced photosynthesis. • lodging (falling over of the plant).

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 3 : Three requirements of good crop management

REQUIREMENTS: GOOD CROP MANAGEMENT

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 4 : Harvesting timing and threshing

A farmer carrying his harvest in Ninh Binh province, Vietnam.

If Then

harvesting is too early,

there will be many immature grains that will reduce head rice yield and quality. Further, these immature rice kernels are very slender and chalky and will result in excessive amounts of bran and broken grains.

harvesting is too late,

many grains are lost due to shattering or drying-out and are cracked during threshing. Cracked grains break during milling.

moisture content is allowed to vary,

grain fissuring (cracking) can occur, along with spoilage through yellowing and the development of odors.

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 4 : Harvesting timing and threshing

Farmer threshing rice panicles in the field.

Settings Value

Drum speed Drum tip speeds for a peg tooth thresher should be 12-16m/sec, or approximately 600rpm. Higher speeds result in higher levels of grain damage while lower speeds increase the amount of grain retained in the panicle.

Fan speed 800-850rpm

Sieve oscillation speed 800-850rpm

Clearance between peg teeth and concave

~25mm

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 5 : The importance of clean paddy

Why is clean paddy rice important?

• has a higher value than grain that is contaminated with straws, chaff, weed seeds, soil, rubbish, and other non-grain materials

• improves the storability of grain • reduces price penalties at the time of milling • improves milling output and quality.

                           

                                                                                

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 5 : The importance of clean paddy

                                                                                                           

Winnowing (100 kg to 3 tonnes per hour) is an important technique for cleaning grain at the farm level. If there is not enough wind, simple electric air fans can be used to separate lighter materials from the grain.

A mechanical seed cleaner, capable of cleaning 10-30 tonnes per hour.

WINNOWING CLEANING GRAIN MECHANICALLY

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 6 : The correct moisture content for storage

Wet spots in the grain due to uneven drying or weed seeds can lead to off odors and discoloration of the grain.

SUNDRYING

Course : Grain QualityModule 2 : Seed to Seed QualityLesson 7 : The correct storage for paddy

                              

                                                                             

Traditional Hermetic

Farmers often store seed and grain in claypots or woven plastic bags. Grain stored under these conditions is often exposed to moisture fluctuation, insects and rodents.

Recycled oil drums and PVC containers can be used as low-cost sealed storage devices for paddy seed and grain.

STORAGE METHODS