GB/T 29371.3-2012Technical rules for seed producing system of two-line hybrid rice - Part 3: Technical rules for seed multiplication of photo/thermo-sensitive genic male sterile line (English PDF)

2.1 Insulation

Breeding field isolation spacing of indica shall be >=200 m; for japonica rice, it shall be >=300 m; or the time interval BETWEEN initial heading stage of other rice AND breeding male sterile line in isolation area shall be >=25d.

2.2 Quarantine

The breeding field is centralized and contiguous, with adequate sunlight, without the same-family plant quarantine objects.

2.3 Cold irrigation breeding water source

With adequate water source, water temperature shall be <=19°C. Capacity of reservoir shall match with available breeding area:

- Capacity of reservoir is below 1×10

7 m

3 , and the available breeding area is below 3 hm

2

;

- Capacity of reservoir is 1×10

7 m

3

- 2×10

7 m

3 , and the available breeding area is

3hm

2

- 13 hm

2

;

- Capacity of reservoir is above 2×10

7 m

3 , and the available breeding area is 13 hm

2 or above.

2.4 Cold irrigation breeding drainage facility standard

The irrigation drainage facility of cold irrigation breeding field shall be based on meeting the inlet water temperature 19 - 20°C of breeding field; the outlet water temperature shall lines

According to the sensitized characteristics of photo-sensitive genic male sterile lines and sowing time at breeding place to determine the initial sowing period of sterile line, it shall arrange the heading and flowering period of male sterile line to be before safe heading period of local rice production.

4.1 Requirement for seeds

4.1.1 Quality

The male sterile line seeds used for breeding shall be basic seeds, with purity of above

99.9%.

4.1.2 Sowing quantity

Male sterile line sowing quantity of early season rice and late season rice is 1.5 kg / 667 m

2

- 2.0 kg / 667 m

2

. The sterile line sowing quantity of middle season rice is 1.0 kg / 667 m

2

- 1. 5 kg / 667 m

2

. And sowing quantity of japonica photo-sensitive genic male sterile lines is 2.0 kg / 667 m

2

- 2.5 kg / 667 m

2

.

Adjust appropriately according to the level of germination rate, weight and size of thousand-seeds, growth duration, and strength of tillering ability. For those with higher germination rate, or lower-weight of thousand-seeds, or longer growth period, or stronger tillering ability, the sowing quantity shall be reduced, otherwise it shall be increased.

4.2 Seed soaking for accelerating germination

For the same breeding base, unify the seed soaking for accelerating germination. Use

"Day soaking - night dew, multiple rise – multiple drop" method to soak seeds. It shall use drug-liquid to soak the seeds for disinfection. Accelerate the germination timely after the seeds absorb adequate water.

4.3 Sowing and seedling

4.3.1 Method of raising seedling

4.3.1.1 Moist seedling

The rice field is ditched and divided by plots. Flat the plot surface. Sow uniformly, with the sowing quantity of 10 kg / 667 m

2

- 15 kg / 667 m

2 , and step-valley after sowing. It shall use thin film to cover, for the early spring sowing.

4.3.1.2 Two-stage seedling

The first stage is dry nursery seedling. Select adequate sunlight and flat dry land for seed bed with the width of 1.2m. Firstly spread a layer of lime or plant ash; then lay abundant

6.1.1 Basal fertilizer

Fertilize 1,000 kg - 1,250 kg of decomposed field-yard manure and 8 kg - 10 kg in total amount of pure N per 667 m

2 , 4 kg - 6 kg in total amount of P 2O5, and 8 kg - 10 kg in total amount of K2O, as the basal fertilizer.

6.1.2 Topdressing

5d-7d after transplanting, topdress 10 kg / 667 m

2

- 12 kg / 667 m

2 of urea, Apply fertilizer depending on the growth of the seedlings. For cold irrigation breeding field, 3 d-6 d before cold water irrigation, topdress 10 kg / 667 m

2 of potassium chloride. Hainan winter breeding should be fertilized in multiple times. The number and the amount of topdressing are determined and depended on the field fertility and the condition of water and fertilizer.

6.2 Irrigating

For cold irrigation breeding field, in addition that it is irrigated by deep water when conducting irrigation treatment, the rest period shall be conducted according to rice planting management method.

6.3 Control and prevention of diseases and pests

It shall be operated by referring to the local control and prevention methods for the same-season rice planting. For cold irrigation breeding field, it shall strength the control and prevention for banded sclerotial blight and rice blast. For autumn breeding field, it shall pay attention to the control and prevention for false smut and rice blast.

7.1 Determination of beginning and ending of cold irrigation

7.1.1 Beginning of cold irrigation

When the groups young-ear differentiation indica-type reaches the end of stage IV (differentiation period of male and female pistil); when the japonica type reaches the end of stage III (differentiation period of spikelet primordia).

7.1.2 Ending of cold irrigation

When the groups panicle differentiation reaches the end of stage VI (meiosis stage).

7.2 Water temperature of cold irrigation field

Keep the water temperature at 2°C - 3°C lower than sterility starting temperature of breeding male sterile lines.

7.3 Cold irrigation depth

Water depth shall be subject to completely submerge the young-ear, and gradually

Remove the single-plant whose particle shape, apiculus color, stigma color, plant height, and plant shape are different from the standard sterile plant. And remove the single-plant whose seed ripening rate of the whole-plant is obviously higher than the standard sterile plant.

8.3 Field inspection

8.3.1 Full heading stage inspection

According to the breed typicality to inspect the uniformity of the group agronomic trait, and according to the anther form and anther dehiscence powder situation to inspect the consistency of the sterile starting point temperature, it is required that the mixed strain rate of the field is <=0.02%,

8.3.2 Inspection before the harvest

According to the breed typicality to re-inspect the uniformity of the group agronomic trait,

According to the single-plant’s ripening situation to inspect the consistency of the group sterile starting point temperature, it is required that the mixed strain rate of the field is

<=0.01%,

9.1 Reaping

It shall be timely to reap when the grain maturity reaches above 85%. Clean up the reaping machinery, containing bags or baskets, etc. before reaping the seeds.

9.2 Drying

Clean the sunning yard, sunning pad, and containing tools before sunning the seeds. The threshed seeds after reaping cannot be heap-covered. Timely clean out the grass impurities. Dry the moisture to 13% (indica) or 14% (japonica) below. When the seeds are bagged, the labels need to be attached inside and outside of the bags, indicating the variety names, origin, and date of manufacture.

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