Department of Botany, Haryana Agricultural University, Hisar-125004
Five genotypes of guar (Cyamopsis tetragonoloba L.) were grown in pots filled with soil. Water stress was created by with-holding irrigation at flower initiation stage. Water stress resulted in decreased RWC in all the genotypes being more in Durgajay but leaf area and leaf dry weight decreased to a lesser extent compared to other varieties. Rate of photosynthesis decreased in all the varieties with the decrease in RWC. The activity of OS, GOGAT and GDH decreased in all the varieties but proline content increased to a greater extent with little genotypic variations. Soluble sugars did not change much with the increase in water deficit except that a decrease was observed in Durgajay. On the other hand, starch content decreased in all the varieties and it was more in Durgajay and less in 19-1-55. The final grain yield as well as the dry matter production was reduced significantly in IC-11521 and FS-277 without any effect in other genotypes. This correlates well with the earlier results of screening in petri dishes trial. Present results indicate that guar is having a greater capacity to recover from stress and genotypic variations do exist in this regard.
