Tamarind monograph.pdf - Crops for the Future

eceptive period. All unpollinated flowers drop within two days. In contrast
in controlled cross pollination fruit set was more than 75% whilst controlled
self-pollination resulted in 2-6% fruit set (Table 6.3) (Nagarajan et al.,
1997). Usha and Singh (1996) also reported that controlled cross pollination
results in higher fruit set and retention in tamarind than when open or selfpollinated.
Fruit set was only 36% with open pollination whereas it increased
to 56% with cross-pollination.
Table 6.3 Fruit setting in tamarind cultivars under open and controlled
pollinations
Treatment Clone
NBN1 NBN2 NBN3 RDB
Open
pollination
(%)
Self
pollination
(%)
Cross
pollination
(%)
1.65
(1.28)
2.40
(1.51)
2.32
(1.51)
6.80
(2.59)
1.15
(1.07)
2.60
(1.59)
92
Patna
1.47
(1.21)
4.60
(2.13)
JRK
1.44
(1.19)
NA
SEM LSD CV
(%)
0.08
0.12
0.17
0.23
10.3
84.20 88.20 87.40 75.80 NA 0.18 0.39
(9.16) (9.39) (9.34) (8.70)
Source: Nagarajan et al., 1997.
Note: NBN, RDB Patna and JRK are tamarind clones identified from
Gottipura, Karnataka State, India. NA=Not available. SEM=Standard error
of means. The values in paranthesis are transformed means (square root
transformation).
Based on the results of controlled pollination experiments, Nagarajan et al.
(1997) suggested that tamarind is a self-incompatible species. No fruit set
was observed following exclusion of pollen during controlled pollination
experiments suggesting that tamarind is not an apomictic species. Similar
observations were also made in an on-going study in Sri Lanka. Although
different clones respond slightly differently in controlled pollination
treatments, the trend of results seems common for all types of tamarind
(Nagarajan et al., 1997).
Tamarind is a predominately outcrossing species with some level of selfing.
This may be the reason for bearing of fruits even in isolated trees. Shanthi
(2003) studied isozyme analysis of the mating system (with Aat, Adh and
Pdh loci) of tamarind using open pollinated seeds from 225 individuals from
Dharmapuri populations in India. Results revealed that single and multilocus
outcrossing rates of tamarind were 0.68 and 0.67 respectively. High
levels of within population variation and low levels of between population
variations observed by Shanthi (2003) also revealed that the species is highly
8.6
3.1