CLIMATE CHANGE IMPACT ON BLACK PEPPER AND CARDAMOM - Climate Dynamics in Horticultural Science - page 204

and night minimum temperature by 0.23 °C (Rao et al., 2009). Correlation
between pepper productivity and climatic parameters at Panniyur based
on climatic data for 11 years showed that maximum temperature and num-
ber of sunshine hours in the first fortnight of March had positive impact
on productivity, while mean relative humidity of the July first fortnight,
number of sunshine hours received during the February first fortnight and
April second fortnight, and mean maximum temperature during the June
second fortnight had negative influence on productivity (Pradeepkumar et
al., 1999). Most of the pepper growing areas of the country shows an in-
creasing trend in temperature and decreasing trend in productivity (Table
11.2).

TABLE 11.2 Trend Analysis of Climatic Variables and Black Pepper Productivity

Place Rainfall T max T Tmin) Productivity

Kerala
Ambalavayal (Wynad)
1979−2004

Decreasing Increasing Increasing No change

Pampadumpara (Idukki)
1986−2004

Decreasing - Increasing Increasing

Panniyur (Cannanore) Decreasing Increasing Increasing Decreasing

1974−2004

Trichur
1980−2004

Decreasing Decreasing No trend Decreasing

Tamil Nadu
Valparai (Coimbatore)
1976−2004

No trend No trend Decreasing No change

Nilgiris
1980−1992

Increasing Increasing Decreasing No change

Pepper productivity is generally higher in higher elevations such as
Wynad and Idukki. Relatively cool climate of these regions may have in-
fluence on productivity. Table 11.3 reveals that the temperature (both T max
and T Tmin) ) Idukki and Wynad is about 6-7 degree lesser than that of plains
viz. Cannanore or Trichur. The total rainfall of these two places is much
lesser when compared to that of Cannanore or Trichur (Table 11.3). This