Phenotypic variation of Autumn and Spring-sown vetch (Vicia sativa ssp.) populations in central Turkey

Abstract

In central Turkey, common vetch (Vicia sativa ssp. sativa) is traditionally grown in spring. Frequent droughts cause crop failures. Autumn sowing can give higher yields, but then winter plant death is a major problem. The objective of this research was to explore and quantify variation available in V. sativa ssp. germplasm for winter hardiness, yield and adaptability. Eleven plant characters were evaluated in 164 vetch populations in autumn and spring sowings over two years, and their inter-relationships were analyzed. Mean winter death was 27% and was greater in the second, colder year, though the magnitude of the coefficient-of-variation was similar in both years (27 and 28%). Autumn-sown plants produced more standing biomass (17%) than spring-sown plants. Winter death was strongly related to other characters, particularly in the colder year. Principle component analysis proved to be efficient at simplifying the results by classifying the eleven variables into three main groups on the basis of seed size, maturity and winter hardiness. There is wide, exploitable phenotypic variation, and enhanced adaptation for autumn sowing could be achieved by selecting for large seeds and early maturity combined with reasonable winter survival.