indian society of plant genetic resources - Bioversity International

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Results and Discussion
The Patterns of Use of Intra-specifi c Diversity
This survey revealed that over the course of three years
between 2008-2010 farmers grew a total of 51 distinct
pearl millet seed lots during the Kharif (monsoon) season.
For purposes of simplicity we split pearl millet varieties
into four major classes of seed varieties: public hybrids,
private hybrids, landraces, and other. Public hybrids
are those varieties that are developed by public sector
research institutes and multiplied by the Rajasthan State
Seed Corporation (RSSC) using hybrid seed production
methods. Some of these varieties are also produced by
private seed companies under licensing agreements
between the state and the private company responsible for
the seed production. Private varieties are those varieties
developed and produced by private companies. Many of
these varieties are developed by multi-national corporations
under the auspices of their nationally recognized entity.
However, in India there are regional-based private seed
companies that are increasingly becoming integrated in
the seed supply and production system. Landraces refer to
any of a number of traditional farmer developed varieties,
which are commonly traded informally and known to be
locally adapted, heterogeneous populations, with various
distinct phenotypic characteristics. The “other” category
refers to advanced generation hybrids, composite varieties,
which are populations or landrace selections that have
been conventionally bred without hybrid technologies, or
commercial grain that has been purchased from the market.
Details regarding these categories and the varieties that
are included therein can be found in Annex 1.
Trend (percentage) in the Cultivation of Pearl Millet
Varieties 2000, 2008-2010
Figure 1 illustrates the trend (percentage) in the use of the
four types of pearl millet varieties. Over the period 2000
to 2008, there has been an increase in the use of hybrid
varieties with a concomitant decrease in the use of landrace
varieties (Fig. 1), but thereafter no signifi cant changes
have been observed. Pearl millet farmers in Rajasthan
still heavily rely on landrace varieties in order to cope
with the marginal, drought-prone environment prevalent
in this region. Nevertheless, over the last 10 years the
predominance of landrace varieties has decreased. It is
suspected that the genetic purity of landrace seed lots is
uncertain in many locations where hybrids are frequently
cultivated. Since this study did not rely on genetic or
morphological characterization of each individual seed
Indian J. Plant Genet. Resour. 25(1): 85–96 (2012)
Curan A Bonham et al.
100
80
60
40
20
0
2000 2008 2009 2010
Private hybrids Public hybrids Landrace Other
Fig. 1: Trend (percentage) in the cultivation of pearl millet
varieties 200, 2008-2010
lot, as has been performed in similar studies (vom Brocke,
2003; Abay et al., 2009), the exact varietal identifi cation
cannot be definitively ascertained. The definitive
categorization of highly cross pollinating crops, such as
pearl millet, by farmers as landraces is diffi cult because of
the genetic plasticity that is exhibited from year to year.
Many farmers may claim to be growing desi (landraces),
but in reality they may be growing advanced generation
hybrids that have taken on the phenotypical qualities of
a landrace due to cross pollination and natural changes
in gene frequencies occurring from one generation to
the next. Therefore, it is expected that the proportion of
farmers claiming to cultivate pure desi landrace varieties
that are in fact actually growing pure landrace varieties
may be much less (Fig. 2).
Number of Farmers Reporting Use and Availability
of Landrace Seed in All Districts
Figure 2 shows the extent to which landrace varieties
are available to farmers in all districts surveyed. In all
districts except in Jalore, farmers tend to use landraces
where available. However, a smaller proportion of farmers
actually utilize the available landraces. Despite the fact
that many varieties are acquired by farmers over time, it
is only a few key varieties which are utilized on a large
scale. Landraces are the most important type of variety
due to their cultivation over an extensive area and frequent
presence on farm. However, private hybrids although not
cultivated on as much land area, are more frequently found
on farms than landraces. Public hybrids are cultivated on
fewer farms, but over a larger area than private hybrids.
Relative Importance of the Four Types of Pearl
Millet Varieties
The relative importance of these variety types is illustrated
in Fig. 3. Of the over 50 varieties recorded by the study,