A field survey was conducted to determine the effect of wind damage on Hevea clones in a 40-hectares polyclonal garden at the Rubber Research Institute of Nigeria (RRIN). Nine Hevea clones were evaluated for resistance to wind damage. These included six local (NIG. 800, 801, 802, 803, 804, 805) and three exotic (PR 107, GT1 and RRIM 707) clones. Parameters assessed were branch/trunk snapping, canopy load damage and root lodging.  A total of 463 trees planted in a sub plot were sampled for each clone replicated thrice in three blocks.  Wind velocity was evaluated for three months during the rain stormy period from August to October, 2006.  Results showed that mean percentage Hevea resistance to wind damage varied among the clones with the least and highest damage ranging from 2.23 to 8.05% in RRIM 707 and NIG 804 clones, respectively and with values between the two extremes.  The low damage level indicated that the clones are generally tolerant to wind damage.  However, the least level of resistance recorded in NIG 804 clone was significantly different from the other clones (LSD=5.83>4.10-3.85) except for NIG 805 clone (LSD= 3.02<3.85) and NIG 802 (LSD=2.94<3.85).  Average wind velocity was generally low (1.7m per sec.) to produce any significant wind damage effect on the branch and trunk.  Effect of wind damage on canopy load was significant (P<0.05).  NIG 804 clone was the most affected (87.83%) while the least affected was in NIG 800 clone (16.42%).  The high percentage of canopy load damage recorded in NIG 804 clone was significantly different from values obtained for other clones (LSD=39.77<71.41 – 46.15) except for NIG 802 clone (LSD=39.77>37.43). The susceptibility of canopy to wind damage was observed to be related to the heavy canopy load bearings. No appreciable incidence of root lodging was obtained.  The present study reports the evaluation of wind damage on Hevea clones which was generally low and also showed that wind damage may not be of serious economic consequence to rubber farmers.

Key words

clones, wind damage, canopy load, clonal garden

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