abstracts - INCDCSZ Brasov

EVALUATION OF YIELD PERFORMANCES OF SOME POTATO CULTIVARS
FROM DIFFERENT MATURITY GROUPS IN A MEDITERRANEAN-TYPE
ENVIRONMENT IN TURKEY
Caliskan M.E. & Caliskan S.
Department of Field Crops, Faculty of Agriculture, Mustafa Kemal University,
31034 Hatay/Turkey, e-mail: mehmet@mku.edu.tr
INTRODUCTION
Potato is grown as early crop during winter and spring months in Mediterranean type
environments in Turkey (Caliskan et al., 1997). This cropping system is characterized with shorter
growing period (80-100 days), short photoperiod (10-12 hours), and high day temperatures (>28 C)
during tuber bulking stage. The potato cultivars bred in North European countries are commonly used
in both main crop and early crop production in Turkey. However, the potato growing conditions in
Mediterranean region are opposite of potato growing conditions in North European countries. The
short photoperiod accelerates tuber initiation, and results in less vegetative development whereas the
high temperature stress limits tuber bulking after mid April. Therefore, selection or improvement of
appropriate cultivars for early production in Mediterranean conditions is very important (Foti, 1999;
Frusciante et al., 1999; Caliskan et al., 1999; Caliskan, 2001). There is also a tendency to recommend
early genotypes for early potato production in Mediterranean type environments due to short growing
period. However, the cultivars can not express their characteristics in most times due to stressful
environment of Mediterranean region. Therefore, specific adaptability of potato cultivars to early
potato production conditions of Mediterranean region is more efficient on their yield and quality
performances than their maturity groups (Caliskan, 2001). Previous findings often indicated that later
maturing genotypes gave the higher yield values than very early or early cultivars. A number of
cultivars have been introduced to Turkey in each year. The evaluation of new cultivars under
Mediterranean conditions is very important to select most suitable cultivars for early potato
production. In this study, the yield performances of sixty five potato cultivars from different maturity
groups were evaluated in a Mediterranean-type environment in Turkey during 2000 and 2004.
MATERIAL AND METHOD
This study was conducted at the Experimental Farm of Agricultural Faculty, Mustafa Kemal
University in Hatay, Turkey (36 o 15’ N, 36 o 30’ E) during winter and spring seasons between 2000 and
2004. The soil of the experimental fields has low organic matter content and was slightly alkaline in
reaction. Hatay province has typical Mediterranean climate conditions with hot-dry summers and
mild-rainy winters.
The number of cultivars varied in years, but sixty five potato cultivars from different maturity
groups were evaluated in total during five year period. The name and maturity groups of the evaluated
cultivars as well as planting and harvesting dates in the experimental years were presented in Table 1.
The experiments were laid out in randomised complete block design with three replications in each
year. Medium size (35-55 mm) seed tubers of cultivars were planted with 70 and 25 cm inter- and
intra-row spacing using a feed assisted planter. Plots were fertilized with 90 kg N, P, K per ha using a
composed fertilizer before planting, and an additional nitrogen dose of 60 kg per ha as ammonium
nitrate was side-dressed at the beginning of tuber bulking. Standard cultural practices were employed
to the plots during growing periods.
RESULTS AND DISCUSSION
The tuber yield values of evaluated cultivars between 2000 and 2004 were presented in Table
1, and overall yield performance of different maturity groups during five-year period was given in
Table 2.
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