Research on Azadirachta indicaand its Planting at Research Institute of Resource Insects, Chinese Academy of Forestry

Foreword

Neem (Azadirachta indica) is not a native species in China. It was first successfully introduced to China (Hainan Province) in 1986. It was introduced to Yunnan and researched in a planned way in 1995. Now it has been cultivated on a large scale.

1 Objective• To afforest ecologically in the dry-hot valley area

to improve its environmental conditions• To establish neem plantation for raw material of

high quality and high output

2 Contents• Study seed sources and technique of introduction• Select fine breed• Explore normal areas• Research on techniques of growing seedlings

and neem afforestation on a large scale• Elementary and concerned research on

afforestation of high quality and high efficiency

3 Methord3.1 Organize a multi-learning team

3.2 Lay emphasis on technological study, demonstration and popularization

3.3 Introduce techniques

• Introduce seed sources from different origin areas

• Collect technical data• Investigate abroad and invite foreign experts

3.4 Renew the introduced techniques

• Comparative tests of seed sources• Comparative tests of different site factors• Verification on the introduced techniques of

growing seedlings and afforestation

3.5 Research on the techniques of growing seedlings and afforestation of neem on a large scale

• Draw lessons from foreign techniques of growing seedlings and afforestation of neem and other similar home species of trees

• Research on the key techniques of growing seedlings on a large scale

• Form a complete set of the concerned techniques with their verification

3.6 Lay down technical specification and operating regulations

3.7 Demonstration and popularization

4 Result of technological study• Some adaptive seed sources were decided• Some individuals were selected with both high

content of Aza-A (max. up to 0.91%) and higher output as well

• Put forward practicable techniques of growing seedlings and afforestation of vast scale and successful popularization in area covered about 20000ha.

5 Some valuable results of researches and tests with new ideas

5.1 The mature criterion of the fruit

When the fruits being mature and with seed-fall of about 30%, collect the whole fruits on a tree (about 63000 fruits) and then separate the yellow from the green ones, both of them were washed and dried in the air.

The test shows that the fruits becoming yellow is not only the standard of seed mature and collection.

0.440.380.32Kernel Aza-A content /%

47.550.7－Kernel yield /%

89.291.438.0Germination rate /%

177.5184.9172.6Kilo-grain weight /g

Seeds from the green

Seeds from the yellow

Seeds from the ground

5.2 Variation of Aza-A content of the kernelThe test result of the seeds exposed to the sun in the production area when the seeds were fresh

0.50The seeds in room

0.44not covered

0.52covered with the netPlastic film on grassland and the seeds on the film

0.50not covered

0.49covered with sun shade netThe seeds on cement ground

Aza-A% *of kernelMethod to dry

* Water content 10%-12% of the determined seeds

The test result of the dry seeds exposed to the sun

0.4459.88

0.4664.56

0.4273.34

0.4670.12

0.4978.00

Aza-A% of kernelGermination rate /%Days exposed to the sun

Aza-A content change of the greensh and yellow to the kernels from the stored seeds

0.31－53

－0.4030

－0.4412

0.460.536

Seeds from MyanmarSeeds from ChinaDuration of store

/months

The determined result of the kernels with different color

0.280.320.530.55Aza-A%

Brown and blackBrownshYellowGreenshColor of

the kernel

5.3 The relationship between Aza content of kernels and the morphology and autumn of the seeds

• No relation between Aza content and autumn of the seeds on the same tree

• The length and width of the seeds and Azacontent is positively correlative(This will be accounted in detail by Dr. Zhang Yanping the next day)

5.4 GeneticsBlossom and pollination

• Blossoming time in a day appears at 18:00-23:00 with the peak time at around 20:00. In the next morning, the pollen will shrink and change to brown

• The result of pollination under artificial control shows the fruits of self-pollination consist of 1%-3% of the fruits under natural condition

• The test by means of RAPD proved that the average outcrossing of neem is 96.27%

96.27Average of cumulative outcrossing rate /%

95.6595.6510010091.3095.6595.65Cumulative outcrossing rate /%

22222323212222Nos. of filial generation

GFEDCBAMaternal plant

Morphological variation

The test by means of AFLP showed that the difference of inter-provenances was less than the difference of intra- provenances

Individual difference in seed output and Aza content

• The capability of seed yield of an individual is comparatively stable

• Difference of seed yield of an individual in a seed source is significant

• Different of Aza-A content of kernel between individuals is relatively significant (from 0.27% to 0.91%)(This will be accounted in detail by Dr. Zhang Yanping the next day)

Vegetative propagation

• Vegetative propagation of neem has been reported abroad

• Our test and practice show that the technique of vegetative propagation can be widely used in growing seedlings of neem and improvement of neem trees. As to the tissue culture, the cost of it is rather high

• Neem can be grafted on Melia toosendan or M. azedarach and the survival rate is not only very high but also the young trees grow faster than those reproduced by seeds

GraftingCan flower after only two months

Grafting is the best way to improve the quality of the seedling. Neem trees developed from grafted seedling can keep their parent characteristics.

Azadirachta indica grafted on Melia toosendan

5.5 The impact of low temperature on growth of neem

Branches, even young trees died, no ripe seedNormalNormalNormalGrowth

HeavyFewA fewNilDegree of cold damage

77785368Annual mean relative humidity /%

1096.41253.7611.1801.2Annual mean rainfall /mm

10.81.82.00.7Annual mean frost days /d

1.50.00.00.0Annual mean days of ≤0 ℃ /d

-1.40.2-1.32.0Extreme low temperature /℃

10.913.014.916.5Mean temperature of the coldest months /℃

18.320.222.023.8Annual mean temperature /℃

JingdongJingguYuanmouYuanjiang

Essential climatic factors and damage done by low temperature to neem trees in test points

The essential climatic factors in the period (1999.12.21-12.31) of the rarely low temperature throughout 40 years and the damage causedby them

0.40.02.00.0Rate of trees of dead stem /%

90.60.317.60.0Rate of trees with dead branches /%

0.780.340.360.0Damage index100.097.798.50.0Rate of the damaged trees /%

76766871Mean relative humidity /%

4000Freezing days /d0230Days with heavy frost /d5558Days with light frost /d4040Days of ≤0 ℃ /d7380Days of <2℃ /d

-1.40.9-1.32.0Extreme low temperature /℃7.29.27.910.5Mean temperature /℃

JingdongJingguYuanmouYuanjiang

On the basis of the above two tables we draw the following preliminary conclusions:

• Extremely low temperature ≥ 2℃ causes no cold damage to neem tree and they grow normally

• Extremely low temperature > 0 ℃ -2℃ causes partial leaves to wither and leaf-fall, but the trees grow normally

• Extremely low temperature ≤ 0 ℃ leads the branches and a part of slender or younger stems to wither and the trees can not grow normally

• Duration of low temperature and damage degree is positively correlative

• When harmful low temperature appears, high humidity causes heavier damage and severe frost and freeze increase much more damage

• The older or stronger trees are more resistant to cold.

6 The experience of growing seedlings on a large scale with seeds of very low germination

• Sow germinated seeds in containers

• Transplant sprouting from pre-germination bed into seedling containers

7 StandardizationQuantitative Degree Standard of Azadirachta indica Seeds

≥80≥90≥95Goodness percentage(%)

<12 <11 <10 Percent moisture (%)

>40 ≥60≥80Germination rate(%)

≥90≥95≥98Cleanliness degree(%)

Grade 3 Grade 2 Grade 1

Grade Item

Quantitative Degree Standard of Azadirachta indica Seedlings

Planting regulation of Azadirachta indica

• Range • Cited document • Cultivation object • Selection of site and provenance • Ground preparation • Harvesting seeds • Seedlings cultivation • Planting • Plantation management • Pest management

Acknowledgment

We sincerely express our thanks to:

Experts from China and other countries

Farmers of production areas

The enterprises and organizations

Thanks !