Geographical location of kokum accessions
Kokum trees were spread throughout the geographical area of Goa, right from northernmost taluk Pernem that adjoins neighbouring state Maharashtra to the southernmost taluk Canacona adjoining Karnataka. All taluks towards coast as well as uplands were covered in the study. The longitude ranged from N 150 45’ 33.8” to N 140 54’ 36.5” (North to South) and the latitude ranged from E 730 42’ 21.6” to E 740 13’ 19.3” (West coast towards inland border). Parthasarathy et al. (2006) conducted a similar biodiversity study on pepper in Kerala.
Geographical Information System (GIS) has been successfully used to study geogr aphical distribution of cultivated species as well as pests of agricultural crops (Hijimans and Spooner, 2001 and Ganeshaiah et al., 2003). Distribution of kokum trees throughout Goa depicted in Goa map shows rich distribution in taluks like Pernem, Bicholim, Ponda and Canacona.
Altitude (in meters from mean sea level) ranged from 6 m to a maximum of 178 m, followed by 153 m and 128 m. Trees located at 6 to 10 m altitude are found towards coast or on river banks of backwaters especially in taluks adjoining coast like Pernem, Bardez, Quepem, Canacona etc. Even trees like Kharekazan-2, 3, 4 and 5 (Acc. Nos. 72, 73, 74 and 75) in Bicholim taluk recorded 6-8m altitude, as they were found along bank of a freshwater stream in Western Ghat region.
Trees at higher altitudes like Gokuldem-1 (Acc. No.198 at 178 m MSL) in Quepem taluk and Cotigaon-1 (Acc. No. 209) and 2 (Acc. No. 210) in Canacona were found on slopes of wildlife sanctuaries of Western Ghats. Other trees found on higher altitudes were Savoi Kamini-3 (Acc. No. 151 at 110m MSL) and Savoi Verem-3 (Acc. No. 153 at 128 m MSL) both found in Ponda taluk. Accessions located in altitude range of 145 to 178 m (red) followed by 112-145 m (orange), 79-112 m (yellow), 46 to 79 m (light green) and 6-46 m (dark green)
3.3.1. Tree shape Canopy shape of each accession studied was recorded. The canopies were basically either pyramidal or conical or of spreading. In total, out of 268 trees studied, 59 (22.01 %) were conical, 111 (41.42 %) were pyramidal, 71 (26.49 %) were pyramidal and spreading, 15 (5.60 %) were spreading, 9 (3.36 %) were pyramidal and drooping and 3 (1.12 %) were conical and medium spreading (Plate 2a to 2e). All types were found in all the taluks. Subash Chandran (1996) reported different canopy shapes viz., drooping and pyramidal shape in kokum trees with 10-15m height. Similar findings were also reported by Korikanthimath et al. (2008), Shinde et al. (2001) and Gawankar et al. (2001) in kokum.
Number of branches
Number of primary branches that arose from main trunk varied from a minimum of one (in several accessions) to a maximum of 42 branches in the accession 119. The number of primary branches was found to have no correlation with the shape of the tree. Number of secondary branches that arose from primary branches ranged from 0 to 156 number and did not play a significant role in deciding the shape of the canopy.Number of tertiary branches that branch out of secondary branches varied from 0 to a maximum of 210 in accessions 20, 260 and 267 followed by 205 branches in accession 36 and 202 branches in accession 51. Presence or absence of tertiary branches was observed to be crucial in deciding the shape of the canopy. Accessions with more number of tertiary branches were either spreading or pyramidal and spreading in shape.
- Central Coastal Agricultural Research Institute, Ela, Old Goa, Goa