Biotech Studies 1995, Vol 4, Num, 1     (Pages: 001-005)

DETERMINATION OF EFFECTIVE METEOROLOGICAL PARAMETERS IN FORECASTING, WINTER WHEAT YIELDS OF STATE FARMS LOCATED IN CENTRAL ANATOLIA

Muzaffer Avcı 1 , Vedat Uzunlu 1

1 Dr. Tarla Bitkileri Merkez Araştırma Enstitüsü, Ankara Viewed : 275 - Downloaded : 140 Forecasting of wheat yield and determinatian of effective weather parameters on grain yield are very important for wheat production and the activities in agricultural economy in Turkey. The objective of this paper was to find out most critical weather parameters affecting wheal yield and thereby to predict yield by employing multiple regression analysis. The wheat yields and monthly precipitation and temperatures of 5 seasons (1989-1994) obtained from State Farms located in different parts of the Central Anatolia were used. Results showed that November precipitation x temperature interaction, April + May rainfall, and June temperature were positive impact on yield.However, single effect of November rainfall had negative effect. The favorable effect of the interaction of November rainfall and temperature may result from the beneficial impacts of it on germination, emergence or the development of the wheat crop. The reason of this kind of explanation because, the emergence of wheat crop in Central Anatolia has been completed in one year out of two. This means that November is an important month in terms of wheat establishment and development. Positive effect of June temperature on grain yield may account for the increase in kernel weight by encouraging protein and carbohydrate synthesis.

This study emphasizes the importance of pre-winter conditions of the Central Anatolia on winler wheat yield and interactions among weather parameters that should be included as independent variables in weather- yield interrelation studies. Keywords : Forecasting of wheat yield, weather parameters; rainfall; temperature