Effect of soil water stress on yield and proline content of four wheat lines.

This field study was conducted to evaluate the effect of drought stress after anthesis on proline accumulation and wheat yield during 2008 at Moghan region. Four lines of bread wheat (N-82-9, N-83-5, N-84-12 and N-85-20) were evaluated into contrasting water regimes (well-watered and drought stressed after anthesis). The trial was carried out in a 4 × 2 factorial experiment based on complete block design with 3 replications. Proline content, total soluble sugar (TSS), seed yield, straw yield, harvest index (HI), 1000 kernel weight, ear length, plant height and tiller number were studied. The SAS software package was used to analyze all the data and means were separated by the least significant difference (LSD) test at P < 0.01. Results showed that proline content and TSS increased by water stress. Seed and straw yield decreased 25% approximately, if water stress occurred after anthesis stage. The highest seed yield observed in line N-82-9 and lowest observed in line N-85-20 under water stress. Under control condition (None stress), line N-82-9 had high seed yield, straw yield, HI and 1000 kernel weight.