In situ and Ex situ Conservation of Commercial Tropical Trees - ITTO

158Number of individual trees sampled at each population.From the basic sampling strategy developed above the number of individualtrees was determined as follows:1. Identify about 15 populations, 9 populations from Kalimantan and 6populations from Sumatera2. Select about 5 sub-populations per population3. Sample systematically 10 unit areas per sub-population4. Sample randomly 10 points, consisting of 5 plus trees and 5 average treesper point areaBased on the above sampling strategy the project has selected 250 plus treesand 250 average trees per population.Number of wildings collected.Wildings identified from sampled parent trees (both plus and average tree)were collected. Each parent tree is represented by 10 wildings. The total wildingscollected in this scheme are thus 2500 from average trees and 2500 from plustrees per population.Nursery establishmentPermanent and temporary nurseries were established in 6 State Owned ForestCompanies. Wildings obtained from target population were raised in each nursery,identified by sampling point and sub-population, and maintained until they wereready to be planted at identified sites. Materials destined for ex situ geneticconservation should remain representative of the source population from whichthey were derived. Thus, nursery technique and maintenance are moreexpensive than routine nursery practices to maintain this genetic identity.Ex situ plantation establishmentEstablishment and maintenance of ex situ conservation plantations is expensive.However, ex situ plantations can be used (1) to safeguard genetic resources oftarget species, (2) as identifiable genetic resources for future breeding andbiotechnology. The criteria for ex situ plantation establishment consists of: (1)site selection, (2) design and size of stand, and (3) isolation between populations.