Improving Drought Tolerance by Exogenous Application of Glycinebetaine and Salicylic Acid in Sunflower

Abstract

Water shortage is a severe threat to the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse affects of drought stress. This study was conducted to examine the possible role of exogenous GB and SA application in improving the yield of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at vegetative stage (irrigation missing at vegetative stage) and water stress at flowering stage (irrigation missing at flowering stage). GB and SA were applied exogenously at 100 and 0.724 mm, respectively, each at the vegetative and at the flowering stage. Control plants did not receive application of GB and SA. Water stress reduced the head diameter, number of achene, 1000‐achene weight, achene yield and oil yield. Nevertheless, exogenous GB and SA application significantly improved these attributes under water stress. However, drought stress increased the free leaf proline and GB, and were further increased by exogenous application of GB and SA. However, exogenous GB application at the flowering stage was more effective than other treatments. Oil contents were also reduced under water stress; however, GB and SA application could not ameliorate the negative effect of water stress on achene oil contents. The effects of water stress and foliar application of GB were more pronounced when applied at the flowering stage than at the vegetative stage. Moreover, exogenous GB application was only beneficial under stress conditions.

Studies on Performance of Drought Tolerant Genotypes Under Drought and Normal Conditions Through Morpho, Physio and Biochemical Attributes of Blackgram (Vigna Mungo L.) and Green Gram (Vigna Radiata L.).

“…This study agreed with many authors, cell elongation of higher plants can be inhibited by interruption of water flow from the xylem to the surrounding elongating cells (Nonami, 1998). Drought caused impaired mitosis; cell elongation and expansion resulted in reduced growth and yield traits (Hussain et al, 2008). This modification in leaf anatomy is one of the basic causes which lead to reduction in average leaf size under water limiting situation Effect of drought stress on cell membrane stability:-The genotypes shows a considerable decrease in the membrane stability in the plants grown under drought stress condition as compared to the irrigated plants for both the crops (Table 7).…”

Rustificação de mudas de eucalipto via aplicação de ácido salicílico

“…O AS é um hormônio vegetal de natureza fenólica, que exerce diferentes funções regulatórias no metabolismo das plantas. A aplicação exógena de AS, em baixas concentrações (10 -3 -10 -6 M), exerce efeito determinante na indução de tolerância, em plantas expostas ao estresse hídrico, como verificado em tomate (Hayat et al 2008), feijão (Senaratna et al 2000), aveia (Bandurska & Stroinski 2005) e girassol (Hussain et al 2008).…”

In vitro screening of potato lines for drought tolerance

“…Drought impairs mitosis, cell elongation and expansion, resulting in a reduction in plant length, leaf area and crop growth (Kaya et al 2006;Hussain et al 2008). Reduction of leaf size is the first morphological manifestation due to drought (Jefferies and MacKerron 1987) associated with reduced light interception and leads to a reduction in dry matter accumulation (Jefferies and MacKerron 1987;Jefferies 1993;Deblonde et al 1999).…”