Data/hora: 17/06/2024 07:18:29

Biblioteca(s): 	Embrapa Soja.	
Data corrente: 	06/04/2004	
Data da última atualização: 	27/07/2007	
Autoria: 	STOLF, R.; MEDRI, M. E.; BROGIN, R. L.; MOLINA, J. C.; SILVEIRA, C. A. da; MARIN, S. R. R.; BINNECK, E.; LEMOS, N. G.; PIOTTO, E. C. S.; DIAS, J.; NEUMAIER, N.; NEPOMUCENO, A. L.	
Título: 	Tolerance to drought in Glycine max (L.) Merril: ecophysiological aspects.	
Ano de publicação: 	2004	
Fonte/Imprenta: 	In: WORLD SOYBEAN RESEARCH CONFERENCE, 7.; INTERNATIONAL SOYBEAN PROCESSING AND UTILIZATION CONFERENCE, 4.; CONGRESSO BRASILEIRO DE SOJA, 3., 2004, Foz do Iguassu. Abstracts of contributed papers and posters. Londrina: Embrapa Soybean, 2004.	
Páginas: 	p. 185.	
Série: 	(Embrapa Soja. Documentos, 228).	
Idioma: 	Inglês	
Notas: 	Editado por Flávio Moscardi, Clara Beatriz Hoffmann-Campo, Odilon Ferreira Saraiva, Paulo Roberto Galerani, Francisco Carlos Krzyzanowski, Mercedes Concordia Carrão-Panizzi.	
Conteúdo: 	One of the main causes on the variation in soybean yields, has been the stress events, caused by climatic adversities such as drought. The aim of this work was to evaluate physiological and morpho-anatomical strategies of two soybean cultivars, Conquista (MGBR-46) and BR-16, tolerant and susceptible to drought, respectively, during two periods of water deficit: 30 and 45 days. The experiment was performed in greenhouse, in a completely randomized design (CRD), in PVC pots with sand, considering the treatments with gravimetric humidity of 15% (field capacity) and 5% (moderate stress). Measurements were made on leaf area, plant height, relative growth rate (RGR), photosynthesis and stomatal conductance. As results, it was observed that the photosynthesis was significantly reduced with 45 days of stress, and the tolerant cultivar presented smaller values of photosynthetic rate. Data on stomatal conductance showed that values weren't significantly different. It was also observed a small reduction in the leaf area between the cultivars in the period of 45 days of treatment. During water stress period, leaf abscission had occurred, which could have contributed to the reduction in leaf area, as well as the reduction in the photosynthetic rate. The relative growth rate, which express the plant growth as a function of dry mass accumulation versus time, presented a significant reduction in the 30 days treatment. Fifteen days after this period, which means 45 days of treatment, the plants of the drought susceptible cultivar in stressed condition, showed loss of dry mass. This result also showed that, during the 30 days treatment plants showed some stress which increased with time. Considering the dry mass of pods, it was observed a significant reduction in the cultivar BR-16 when compared to Conquista and, also, inside each cultivar in the different treatments. It shows that this reduction in total dry mass could be affecting the yield of these cultivars. The anatomical study, using permanent slides of leaf and root was done using the method of paraffin inclusion. Quantitative analysis were performed on palisade and spongy parenchyma and intercellular space. Next, it will be doing molecular studies to understand the soybean tolerance strategies to drought, for example how genes are differentially expressed during this period.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Soja (CNPSO)	
Exemplares: 	CNPSO - (23728-1) - UMT - PL - -- - RF 633.34072 - W927a -  - DIS