Nitric oxide affects phosphorus redistribution and senescence in sotybean leaves during P starvation

DELGADO I; MATEOS R; SANTA MARIA G.E.; SIMONTACCHI M

Buenos Aires

Congreso; VIII International Congress, Society for Free Radical Biology and Medicine, South American Group.; 2013

VIII International Congress, Society for Free Radical Biology and Medicine, South American Group.

Nitric oxide affects phosphorus redistribution and senescence in soybean leaves during P starvation Delgado1 I., Mateos1 R., Santa Mar¨ªa2 GE., Simontacchi1 M. 1INFIVE, UNLP-CONICET, La Plata, Buenos Aires, Argentina. 2INTECH, UNSAM-CONICET, Chascom¨²s, Buenos Aires, Argentina Phosphorus (P) is an essential macronutrient, which usually acts as a limiting factor in plant growth and productivity. The influence of NO supplementation, known as a regulator of many aspects of plant physiology, was evaluated through the course of P deficiency in soybean plants. Seven-day-old plants cultured in nutrient solution were exposed to either adequate P supply (0.5 mM H3PO4) or P starvation (without addition of P) for three weeks. P-deficient plants were treated with S-nitrosoglutathione (GSNO) added in the nutrient solution. Leaf functionality was evaluated through chlorophyll content and quantum yield of photosystem II (¦µPSII).P content was determined spectrophotometrically. In the oldest leaves, P concentration dropped from 14¡À1 ¦Ìg g-1 FW to 0.49¡À0.05 ¦Ìg g-1 FW during P starvation. Chlorophyll and ¦µPSII also decreased as a consequence of treatment (45 and 54%, respectively compared to control values). P-deficient leaves enhance their P concentration by 50% when 50 ¦ÌM GSNO was present. Moreover, the addition of NO kept photosynthetic related parameters at the same level founded in well supplied plants. These results suggest a role for NO in preserving photosynthetic activity close to normal values and influencing P remobilization from old to young leaves in plants growing under low P conditions. In the oldest leaves, P concentration dropped from 14¡À1 ¦Ìg g-1 FW to 0.49¡À0.05 ¦Ìg g-1 FW during P starvation. Chlorophyll and ¦µPSII also decreased as a consequence of treatment (45 and 54%, respectively compared to control values). P-deficient leaves enhance their P concentration by 50% when 50 ¦ÌM GSNO was present. Moreover, the addition of NO kept photosynthetic related parameters at the same level founded in well supplied plants. These results suggest a role for NO in preserving photosynthetic activity close to normal values and influencing P remobilization from old to young leaves in plants growing under low P conditions. 1INFIVE, UNLP-CONICET, La Plata, Buenos Aires, Argentina. 2INTECH, UNSAM-CONICET, Chascom¨²s, Buenos Aires, Argentina Phosphorus (P) is an essential macronutrient, which usually acts as a limiting factor in plant growth and productivity. The influence of NO supplementation, known as a regulator of many aspects of plant physiology, was evaluated through the course of P deficiency in soybean plants. Seven-day-old plants cultured in nutrient solution were exposed to either adequate P supply (0.5 mM H3PO4) or P starvation (without addition of P) for three weeks. P-deficient plants were treated with S-nitrosoglutathione (GSNO) added in the nutrient solution. Leaf functionality was evaluated through chlorophyll content and quantum yield of photosystem II (¦µPSII).P content was determined spectrophotometrically. In the oldest leaves, P concentration dropped from 14¡À1 ¦Ìg g-1 FW to 0.49¡À0.05 ¦Ìg g-1 FW during P starvation. Chlorophyll and ¦µPSII also decreased as a consequence of treatment (45 and 54%, respectively compared to control values). P-deficient leaves enhance their P concentration by 50% when 50 ¦ÌM GSNO was present. Moreover, the addition of NO kept photosynthetic related parameters at the same level founded in well supplied plants. These results suggest a role for NO in preserving photosynthetic activity close to normal values and influencing P remobilization from old to young leaves in plants growing under low P conditions. In the oldest leaves, P concentration dropped from 14¡À1 ¦Ìg g-1 FW to 0.49¡À0.05 ¦Ìg g-1 FW during P starvation. Chlorophyll and ¦µPSII also decreased as a consequence of treatment (45 and 54%, respectively compared to control values). P-deficient leaves enhance their P concentration by 50% when 50 ¦ÌM GSNO was present. Moreover, the addition of NO kept photosynthetic related parameters at the same level founded in well supplied plants. These results suggest a role for NO in preserving photosynthetic activity close to normal values and influencing P remobilization from old to young leaves in plants growing under low P conditions.