Sensitivity of Individual Leaves of Brassica Species to Water Stress at Different Growth Stages

Leaf expansion and senescence of two oilseed Brassica species, Brassica juncea and B. napus monitored at various water stress and recovery cycles throughout the maturity period revealed that reduction in total leaf area was faster when stress was imposed during reproductive periods. Substantial differences were observed in leaf expansion at different insertions. Senescence started 4 to 5 days after floral bud appearance and increased linearly with plant age. Water stress hastened leaf senescence and the rates were higher in B. napus than in B. juncea.