Suitable criteria for drought-tolerant peach rootstocks grown in northern Thailand

Abstract

Peach growing in rainfed areas in the hi ghlands of northern Thailand is suffering from drought conditions, which are becoming increasingly severe every y ear. Drought tol erant rootstocks provide one option to all eviate this problem. Thus, this study aims to find some guides for selecting drought -tolerant peach rootstocks. The local peach vari ety ‘Red Angkhang’ and 3 new hybrid cultivars ‘42047T1’, ‘43060T1’ and ‘43087T2’ were used in this study. Two-y ear-old peach seedlings of each cultivar were grown in pots and divided into 2 groups. The first group consisted of well - watered plants (100% of evapotranspiration) and the second group consisted of water-deficit plants which received only 30% of evapotranspiration for 5 weeks. After that, the water- defi cit peach seedlings were re-watered in the same manner as the well-watered plants f or 2 weeks. Water stress led to a decrease in growth in all cultivars. T h e water- deficit tol erance of Red Angkhang was comparable to that of the new hybrid 42047T1, but the two cultivars used different mechanisms: Red Angkhang responded to water deficit by increasing only the root dry wei ght while hybrid 42047T1 also accumulated sorbitol. The 43060T1 and 43087T2 h y b r i d s were l ess tol erant to water defi cit and responded by decreasing the root dry wei ght with no sorbitol accumulation. From this study , we suggest that root dry wei ght and sorbitol concentration can be used to screen drought tolerant rootstocks in peach in northern Thailand.

Keywords

• peach rootstock
• Prunus persica
• drought tol erance
• root growth
• sorbitol accumulation