Tamarind monograph.pdf - Crops for the Future
Tamarind monograph.pdf - Crops for the Future
Tamarind monograph.pdf - Crops for the Future
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Table 7.1 Variation of characters observed <strong>for</strong> tamarind<br />
Character Variation<br />
Terminal shoot length Short-long<br />
Flowering behaviour Early-mid-late<br />
Number of primary branches 5-8<br />
Number of secondary branches 30-63<br />
Number of tertiary branches 45-91<br />
Number of inflorescences/branch 531-990<br />
Number of flowers/branch 5697-15587<br />
Number of fruits/branch 748-1595<br />
Pod length (cm) 4-30<br />
Pod width (cm) 1.9-4.0<br />
Pod weight (g) 4.5-60.0<br />
Amount of pulp in ripened fruit (%) 30-50<br />
Single seed weight (g) 0.8-1.2<br />
Number of seeds/pod 4-10<br />
Seed weight (g) 1.6-10.0<br />
Sweetness of pulp Sweet-sour<br />
Fibre content Low-high<br />
Pod yield per plant (kg) Very variable<br />
Source: Bennet et al., 1997; Challapilli et al., 1995; Divakara,<br />
2002; Shanthi, 2003<br />
The mean total genetic variation (HT) of <strong>the</strong> 10 tamarind populations was<br />
0.322. The total genetic variation within population (HS) was 0.291 whilst<br />
variation between populations (DST) was 0.03. The relative extent of gene<br />
differentiation among populations (GST) was identified as 0.115 (Shanthi,<br />
2003). Even though this showed a low level of genetic diversity it was<br />
mainly because <strong>the</strong> populations sampled were from a small geographic<br />
region. A high level of within population variation and low level of between<br />
population variations also revealed that <strong>the</strong> species is highly outcrossing, and<br />
<strong>the</strong>re is ample individual variation to use in genetic improvement.<br />
Based on <strong>the</strong> assessment of candidate ‘plus’ trees and <strong>the</strong>ir progenies,<br />
Shanthi (2003) concluded that pod size, tree height, number of flowers,<br />
number of inflorescences and number of tertiary branches could be used as<br />
measures <strong>for</strong> evaluating tamarind trees in order to select superior trees <strong>for</strong><br />
fur<strong>the</strong>r evaluation.<br />
The experiments carried out in Coimbatore revealed that <strong>the</strong> highest<br />
phenotypic variation occurred <strong>for</strong> pod length and <strong>the</strong> lowest <strong>for</strong> seed weight<br />
whilst <strong>the</strong> maximum genotypic variation has been observed <strong>for</strong> pulp weight.<br />
The highest phenotypic and genotypic coefficients of variation have been<br />
recorded <strong>for</strong> pulp weight (Chundawat, 1990; Challapilli et al., 1995;<br />
96