Cold Resistance Analysis of Neem Provenances

Neem grows well in the hot-dry valley in China, but it is easy to be harmed by cold.The cold resistance of 4 provenances was valued through tissue browning method, membrane fatty acid analysis and the electric conductivity method which Logistic equation was used to determine the inflexion temperature.The results showed that:(1)neem is a plant which has low cold resistance,short cold temperature below 0 ℃ can damage its tender leaves, and 1h temperature below -1 ℃ will lead part of infant seedlings to death; (2) the cold resistant capability has no distinct difference among neem provenances; (3) membrane fatty acid content of leaves has no correlative relation with cold resistance; (4)the medium lethal temperatures of 4 neem provenances are -1.651,-1.675,-1.75,-1.682 ℃.According to the results above-mentioned and the results of freezing experiment, the cold resistance sequence of neem provenances is IND95003IND95004IND95001IND95002.The results showed that it should be careful to import neem to cold zones in China, and IND95003 can be used in the zones with light frost.