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Indicadores de defici?ncia h?drica em tr?s variedades de milho (Zea Marys L) / Indicators of water deficiency in three maize varieties (Zea Marys L)

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Previous issue date: 1978-07-10 / A study was made of the effect of water stress on
three corn (Zea mays L.) cultivars: Piranao, Centralmex and
IPEACS III.
Under the effect of a - 15 atm stress (using mannitol
as osmoticum), Centralmex showed the highest percent germination
while IPEACS III showed the lowest. The germination of Piran?o
seeds fell in between. There also differences in root and
coleoptile growths of the three varieties as compared to that of
the controls (germinated in demineralized water).
At a more advanced stage of grouth (6-8 leaves, plants
in pots kept in a greenhouse), the soil-water stress affected
the plants differently. IPEACS III continued to be severely
affected but Piran?o was now the least affected, with Centralmex
falling in between.
The effects of water stress upon the plant metabolic
patterns resulted in a increase in the leaf content of nitrate-N,
free amino-N, ammonia-N, free proline and soluble sugars.181
There was on the other hand a reduction in nitrate reductase
activity and protein content.
Although the same general metabolic pattern was
observed for the three varieties, significant differences
could be detected among the varieties. These results
indicated that the greenhouse environment was adequate for
the study of plant responses to water stress, even enabling
the distinction between varietal differences.
The content of free amino-N and soluble sugars in
the plant leaves showed a higher sensitivity to moderate water
stress than the other indicators. A special attention was
given to the study of the increase in free proline levels in
the leaves. The ellucidation of the factors governing the
relative accumulation of this metabolite in corn leaves
requires more detailed studies. Only then could proline
content be considered a safe indicator of water stress
resistance for corn plants.
The plants under water stress were also submitted to
growth analysis. This test was very efficient for the study
of dry weight and leaf expansion variation among varieties.
The results of this study shows that three main
factors are responsible for the plant resistance to water
stress, namely:
a. Tolerance to dehydration (differences in R.W.C.)
b. resistance to loss in protein (differences in
protein-N levels and free-N/protein-N ratios)182
c. increasc in root/shoot ratios.
The present study shows the necessity of experiments
with field grown plants, to check the sensitivity of the
various factors studied and to compare the behavior of
different corn varieties in the field with that in
greenhouse. / Tr?s variedades de milho (Zea mays L.), Piran?o, Centralmex e IPEACS III, foram submetidas a stress h?drico em
duas fases do crescimento vegetativo.
As diferen?as na taxa e percentagem final de germina-
??o, alongamento da raiz e do cole?ptilo foram avaliadas nas
tr?s variedades, quando submetidos a um stress osm?tico de
-15 atmosferas, usando-se manitol como osmoticum. Centralmex
mostrou a maior percentagem de germina??o final nestas candi-
??es e IPEACS III, a menor; Piran?o apresentou um comportamento intermedi?rio. Diferen?as entre as variedades nos respectivos percentuais de alongamento da raiz e cole?ptilo foram
notadas ao serem comparadas com seus controles mantidos em
?gua deionizada.
Quando as variedades foram comparadas em um est?gio
mais avan?ado de crescimento (6-8 folhas), e o stress h?drico
induzido por desseca??o progressiva do solo, em casa de vegeta??o, a variedade IPEACS III mostrou-se severamente afetada,Piran?o, relativamente, a menos afetada, apresentando Centralmex
um comportamento intermedi?rio. Neste ?ltimo est?gio de
crescimento, fez- se uma compara??o da sensibilidade de distintos indicadores metab?licos ? defici?ncia h?drica.
Com rela??o ao metabolismo de N, foram avaliados os
teores foliares de N-n?trico, N-amoniacal, N-amino livre, prolina e N-proteico. No que diz respeito ao metabolismo de carbohidratos, avaliou-se o teor foliar de carbohidratos sol?veis.
Foram observados incrementos nos teores de N-amoniacal, N-n?-
trico, N-amino livre, prolina e carbohidratos sol?veis. Concomitantemente, observou-se decr?scimos para o teor de N-proteico e a atividade de nitrato-reductase. Este padr?o geral de
varia??o, em resposta a stress h?drico, se expressou em forma
diferencial (estatisticamente significativa) entre variedades,
indicando que, o ambiente proporcionado pela casa de vegeta??o
foi apropriado para a separa??o dos efeitos decorrentes do
stress h?drico daqueles devidos ?s caracter?sticas varietais.
Os teores de N-amino livre e carbohidrato sol?vel mostraram uma maior sensibilidade a deficits h?dricos moderados.
Em adi??o aos indicadores metab?licos, realizou-se a
an?lise de crescimento, que mostrou ser um procedimento apropriado para descrever as varia??es em taxas de acumula??o de
mat?ria seca e expans?o de ?rea foliar entre as variedades.
Os dados sugeriram que, as diferen?as observadas em
resist?ncia ao stress h?drico entre as variedades podem ser
decorrentes de tr?s tipos de efeitos: toler?ncia ? desidrata ??o (diferen?as em C.H.R.), toler?ncia a perda de prote?nas
(diferen?as nos teores de N-proteico e na rela??o N-sol?vel/
N-proteico) e incrementos na rela??o raiz/parte a?rea.
A evolu??o do teor foliar de prolina foi particularmente observada nos tr?s cultivares, visando-se ligar o seu
teor ? explica??o das diferen?as em sensibilidade (ou resist?ncia) ao stress h?drico. Os resultados atualmente obtidos, mostraram que, pelo menos em milho, ? necess?rio um estudo mais
detido dos fatores que governam a acumula??o deste metab?lito,
antes de aplicar-se indiscriminadamente este par?metro como
indicador de resist?ncia ? seca.
Finalmente, foi destacada a necessidade de experimenta??o direta no campo, visando a determina??o do grau de sensibilidade dos distintos indicadores e a quantifica??o das diferen?as com respeito ao comportamento das variedades em casa
de vegeta??o.

Identiferoai:union.ndltd.org:IBICT/oai:localhost:jspui/1634
Date10 July 1978
CreatorsRossiello, Roberto Oscar Pereyra
ContributorsFernandes, Manlio Silvestre
PublisherUniversidade Federal Rural do Rio de Janeiro, Programa de P?s-Gradua??o em Agronomia e Ci?ncia do Solo, UFRRJ, Brasil, Instituto de Agronomia
Source SetsIBICT Brazilian ETDs
LanguagePortuguese
Detected LanguageEnglish
Typeinfo:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis
Formatapplication/pdf
Sourcereponame:Biblioteca Digital de Teses e Dissertações da UFRRJ, instname:Universidade Federal Rural do Rio de Janeiro, instacron:UFRRJ
Rightsinfo:eu-repo/semantics/openAccess
RelationACEVEDO, E., HSIAO, T.C. e HENDERSON, D.W., 1971. Immediate and subsequent growth responses of maize leaves to changes in water status. Plant Physiol., 48:631-636. ALLAWAY, W.G. e MILTHORPE, F.L., 1976. Structure and functioning of stomata in: Water deficits and plant growth. Vol. IV _ T.T. Kozlowski (Ed.) Academic Press, New York, London. ARAD, S. e RICHMOND, A.E., 1976. Leaf cell water and enzyme activity. Plant Physiol., 57:656-658. ARNON, I., 1975a. Physiological principles of dryland crop production in: Physiological aspects of dryland farming. U.S. Gupta (Ed.). Applied Science Publishers Ltd., England, ARNON, I., 1975b. Mineral nutrition of maize. International Potash Institute. Bern-Worblaufen, Switzerland. AUNG, L.H., 1974. Root-shoot relationships in: The plant root and its environment. E.W. Carson (Ed.). University Press of Virginia. Charlottesville.BARDZIK, J.M., MARSH Jr., H.V. e HAVIS, J.R., 1971. Effects of water stress on the activities of three enzymes in maize seedlings. Plant Physiol. , 47:828-831. BARLOW, E.W.R. e BOERSMA. , 1976. Interaction between leaf elongation, photosynthcsis and carbohydrate levels ofwaterstressed corn seedlings. Agron. J., 68:923-927. BARLOW, E.W.R., BOERSMA, L. e YOUNG, J.L., 1976a. Root temperature and soil water potential effects on growth and soluble carbohydrate concentration of corn seedlings. Crop Sci., 16: 59-62. BARLOW, E.W.R., CHING, T.M. e BOERSMIA, L., 1976b. Leaf growth in relation to ATP levels in water stressed corn plants. Crop Sci., 16:405-407. BARRS, H.D. e WEATHERLEY, P.E., 1962. A re-examination of the relative turgidity technique for estimating water deficits in leaves. Aust. J . Biol. Sci., 15:413-428. BASSIRI, A., KHOSH-KHUI, M. e ROUHANI, I., 1977. The influences of simulated moisture stress conditions and osmotic substrates on germination and growth of cultivated and wild safflowers. J. Agri. Sci., Camb., 88:95-100. BATES, L.S., WALDREN, R.P. e TEARE, I.D., 1973. Rapid determination of free proline for water-stress studies. Plant Soil 39:205-207. BEADLE,C.L., STEVENSON, K.R., NEUMAN, H.H., THURTELL, G.W. e KING, K.W., 1973. Diffusive resistence, transpiration and185 photosynthes is in single leaves of corn and sorghum in relation to leaf water potential. Can. J. Plant. Sci., 53: 537- 544; BIERHUIZEN, E.J., 1976. Irrigation and water use efficicncy. in water anti plant life. Ecological Studies vol. 19. O. Lange, L. Kappen C.E.D. scchulze (Ed. ). Springer-Verlag. Berlin Heidelberg. New York. BLUM, A. e EBERCON, A., 1976. Genotypic responses to drought stress. III. Free proline accumulation and drought resistence. Crop Sci., 16:428-431. BOGGES, S.F., PALEG, L.G. e ASPINALL, D., 1975. 4' - pyrroline- 5-carboxylic acid dehydrogenase in barley, a proline-accumulanting specie. Plant Physiol., 56:259-262. BOGGES, S.F., PALEG, L.G. e ASPINALL, D., 1976. Stress metabolism IX. The significance of end-product inhibition of proline biosynthesis and of compartimentation in relation to stress induced proline accumulation. Aust. J. Plant Physiol. 3:503-511. BOYER, J.S., 1970a. Leaf enlargement and metabolic rates of corn, soybean and sunfflower at various leaf water potentials. Plant Physiol., 46:233-235. BOYER, J.S., 1970b. Differing sensitivity of photosynthesis to low leaf water potentials in corn and soybean. Plant physiol., 46:236-239. BOYER, J.S., 1976. Water deficits and photosynthesis. in: Wa-ter deficits and plant growth. Vol IV. T.T. Kozlowski (Ed.) Acadcmic Prcss, New York, London. BOYER, J.S. e McPHERSON, H.G., 1975. Physiology of water de ficits in cereal grains. Advan. Agron., 27:1-23. BREMNER, J.M., 1965. Inorganic forms of nitrogen. In: Methods of soil analysis, Vol 2. C.A. Black (Ed.) Am. Soc. Agron. n? 9, Madison, Wisconsin. BREMNER, J.M. e KEENEY, D.R., 1965. Steam destillation methods for determination of ammonium, nitrate and nitrite. Analytica Chimica Acta., 32:485-495. BROWN, R.H. e BLASER, R.E., 1970. Soil moisture and temperature effects on growth and soluble carbohydrates of orchaedgrass (Dactylis glomerata). Crop Sci., 10:213-21. CAMPOS, A.C. e TOZANI, R., 1973. Rea??es de pl?ntulas de arroz (Oryza sativa L.) ao clorato de pot?ssio. Arq. Univ. Fed. Rural Rio de Janeiro., 3:31-37. CATSKY, J., 1974. Direct methods of water content determinative. In: Methods of studying plant water relations. Ecological studies. Vol 9. B. Slavik (Ed.). Springer-Verlag. Berlin-Heidelberg, New York. CHEN, D.; KESSLER, B. e MONSELISE, S.P., 196.4. Studies on water regime and nitrogen metabolism of citrus seedling grown under water stress. Plant Physiol., 39:379-386. CHU, T.M.; ASPINALL, D. e PALEG, L.G., 1974. Stress metabolism. XI. Temperature stress. and t h e accumulation of proline in187 barley and radish. Aust. J. Plant Physiol. 1:87-97. CHU, T.M.; ASPINALL, D. e PALEG, L.G., 1976a. stress metabolism VII. Salinity and prolinc accumulation in barley. Aust. J. Plant Physiol., 3:219-228. CHU, T.M.; ASPINALL, D. e PXLEG., L.G., 1976b. Stress metabolism VIII. Specific ion effects on proline accumulation in barley. Aust. J. Plant Physiol., 3:503-511. COBB III, B.F.; CONTE, F.S. e EDWARDS, M. A., 1975. Free aminoacids and osmorregulation in Penaeid shrimp. J. Agric. Food. Chem., 23:1170-1173. COOPER, J.P., 1970. Potential production and energy conversion in temperate and tropical grasses. Herb. Abstr., 40:1-15. COOPER, C.L. e MacDONALD, P.W., 1970. Energetics of early seedling growth in corn (Zea mays L.). Crop. Sci., 10:136-139. CRAM, W.J., 1976. Negative feedback regulation of transport in cells. The maintenance of turgor, volume and nutrient supply. In: Encyclopedia of plant physiology, New Series, vol. 2. Part A. U. Luttge e M.G. Pitman (Ed.). Springer-Verlag, Berlin-Heidelberg, New York. CROY, L.I. e HAGEMAN, R.H., 1970. Relationship of nitrate reductase activity to grain protein production in wheat.Crop. Sci., 10:280-285. CUTLER, J.M. e RAINS, D.W., 1977. Effects of irrigation history on responses of cotton to subsequent water stress. Crop. Sci., 17:329-334.188 DAINTY, J., 1976. Water relations of plants cells. in: Encyclopedia of plant physiology. New Series. Vol 2. Part A. U. Lutge e M.G. Pitman (Ed.). Springer-Verlag. Berlin-HeidelbergNew York. DECKARD, E.L.; LAMBERT, R.J. e HAGEMAN, R.H., 1973. Nitrate reductase activity in corn leaves as related to yields of grain and grain protein. Crop. Sci., 13:343-350. DENMEAD, O.T. e SHAW, R.H., 1960. the effects of soil moisture stress at different stages of growth on the development and yield of corn. Agron. J., 52:272-274. DILLEY, D.R.; HEGGESTAD, H.E.; POWERS, W.L. e WEISER, C.J., 1975. Environmental stress. in: Crop productivity. Research imperatives. A.W. Brown; T.C. Byerly; M. Gibbs e A.San Pietro (Ed.). Michigan Agric. Sta., Charles Kettering Foundation. DONALD, C.M., 1963. Competition among crop and pasture plants. Advan. Agron., 15:1-118. DOVE, L.D., 1969. Phosphate absorption by air-stressed root systems. Planta, 86:1-9. DOWNEY, L.A. e MILLER, J.W., 1971. Rapid measurements of relative turgidity in maize (Zea mays L.). New Phytol., 70: 555- 560. DRAPER, S.R., 1975. Aminoacid changes associated with the development of cold hardiness in perennial ryegrass. J. Sci. Fd. Agric., 26:1171-1176. ECK, H.V. e HAGEMAN, R.H., 1974. Nitrate reductase activity in189 sudangrass cultivars. Crop Sci., 14:283-287. ECK, H.V.; GILMORE, E.C.; FERGUSON, D.B. e WILSON, G.C., 1975. Heritability of nitrate reductase and cyanide levels in seedlings of grain sorghum cultivars. Crop Sci., 15:421-424. EILRICH, G.L. e HAGEMAN, R.H., 1973. Nitrate reductase activity and its relationship to accumulation, of vegetative and grain nitrogen in wheat (Triticum aestivum L.).Crop Sci., 13:59-65. FANOUS, M.A., 1967. Test for drought resistance in Pearl millet (Pennistetum typhoideum). Agron. J., 59:337-340. FERNANDES, M.S., 1974. Effects of light and temperature on the nitrogen metabolism of tropical rice. Ph.D. Thesis, Michigan State University, 80p. FERNANDES, M.S., 1977. Absor??o e metabolismo de nitrog?nio em plantas. Instituto de Agronomia da U.F.R.R.J., Boletim n? 1 (no prelo). FRANCIS, C.A.; RUTGER, J.N.e PALMER, A.F.E., 1969. A rapid method for plant leaf ?rea estimation in maize (Zea mays L.). Crop Sci., 9:537-539. GALVAO, J.D., 1974. Comportamento do milho Piran?o (Braqu?tico-2) e de milhos de porte normal em diferentes n?veis de nitrog?nio e popula??es de plantas. Tese apresentada ? Escola Superior de Agricultura "Luiz de Queiroz" da Universidade de S?o Paulo, para a obten??o do t?tulo de Doutor. Piracicaba, S?o Paulo., 93p.190 GARDNER, W.H., 1965. Water Content. in: Method of soil analysys. Vol I., C.A. Black (Ed.). Am. Soc. Agron. N? 9., Madison, Wisconsin. GATES, C.T., 1964. The effect of water stress on plant growth. J. Australian Inst. Agri. Sci., 30:3-22. GATES, C.T., 1968. Water deficits and growth of herbaceous plants. in: Water deficits and plant growth. Vol II., T. T. Kozlowski (Ed.). Academic Press, New York, Londow. GREENWAY, H.e LEAHY, M., 1970. Effects of rapidly and slowly permeating osmotica on metabolism. Plant Physiol., 46: 259- 262. GILES,K.L.; BEARDSELL, M.F. e COHEN, D., 1974. Cellular and ultrastructural changes in mesophyll and bundle sheath cells of maize in response to water stress. Plant Physiol., 54:208- 212. GILES, K.L.; COHEN, D. e BEARDSELL, M.F., 1976. Effects of water stress on the ultrastructure of leaf cells of sorghum bicolor. Plant Physiol., 57:l-14. GOODMAN, P.J.; HUGHES, D.M.; FOTHERGILL, M. e ELLIS, P.B., 1974. Genetic variation in the activity of nitrate reductase in lolium. Plant Soil., 41:435-443. HANSON, A.D.; NELSEN, C.A. e EVERSON, E.H., 1977. Evaluation of Free proline accumulation as an index of drought resistance using two contrasting barley cultivars. Crop Sci., l7: 722-726.191 HEBER, U. e SANTARIUS, K.A., 1976. Water stress during freezing. in: Water and plant life. Ecological Studies. Vol 19. O. Lange; L. Kappen e E.D. Schulze (Ed.). Springer-Verlag Berlin, Heidelberg, New York. HELMERICK, R.H. e PFEIFER, R.P., 1954. Differential varietal responses of winter wheat germination and early growth to controlled limited moisture conditions. Agron. J., 46:560- 562. HENZELL, R.G.; McCREE, K.J.; van BAVEL, C.H.M. e SCHERTZ, K.F., 1975. Method for screening sorghum genotypes for stomatal sensitivity to water deficits.Crop Sci., 15:516-518. HILLEL, D., 1972. Soil moisture and seed germination. in: Water deficits and plant growth. Vol III, T.T. Kozlowski, (Ed.). Academic Press., New York and Londow. HSIAO, T.C., 1970. Rapid changes in levels of polyribosomes in Zea mays in response to water stress. Plant Physiol., 46: 281-285. HSIAO, T.C., 1973. Plant responses to water stress. Ann. Rev. Plant Physiol., 24:519-570. HSIAO, T.C. e ACEVEDO, E., 1974. Plant responses to water deficits, water-use efficiency, and drought resistence. Agric. Meteorol., 14:59-84. HSIAO, T.C.; ACEVEDO, E.; FERERES, E. e HENDERSON, D.W., 1976a. Stress metabolism. Water stress, growth and osmotic adjustment. Phil. Trans. R. Soc. Lond. B., 273:479-500.192 HSIAO, T.C.; FERERES, E.; ACEVEDO, E. e HENDERSON, D.W., 1976b. Water stress and dynamics of growth and yield of crop plants. In: Water and plant life. Ecological stud?es. Vol 19., O. Lange, L. Kappen e E.D. Schulze (Ed.). Springer-Verlag, Berlin, Heidelberg; New York. HUFFAKER, R.C.; RADIN, T.; KLEINKOPF, G.E. e COX, E.L., 1970. Effects of mild water stress on enzymes of nitrate assimilation and of the carboxylative phase of photo-synthesisin barley. Crop Sci., 10:471-474. HUFFAKER, R.C. e PETERSON, L.W., 1974. Protein turnover in plants and possible means of its regulation. Ann. Rev. Plant Physiol., 25:363-389. HURD, E.A.; 1976. Plant breeding for drought resistance. In: - Water deficits and plant growth. Vol IV. T. T. Kozlowski (Ed.). Academic Press, New York, San Francisco, London. HURD, E.A. e SPRATT, E.D., 1975. Root patterns in crops as related to water and nutrient uptake. In: Physiological as pects of dryland farming. U.S. Gupta (Ed.). Applied Science Publishers Ltd., England. ITAI, C. e BENZIONI, A., 1976; Water stress and hormonal response. In: Water and plant life. Ecological Studies, Vol 19, O.L. Lange, L. Kappen e E.D. Schulze (Ed.). Springer-Verlag, Berlin, Heidelberg, New York. JACCOUD, A. e CASTRO, A.F. de, 1974. Curvas de caracteriza- ??o de umidade dos solos da ?rea da Universidade Federal Rural do Rio de Janeiro - Munic?pio de Itagua?. Anais do193 D?cimo Quarto Congresso Brasileiro de Ci?ncia do Solo. Santa Maria, RS., pp.150-178. JAWORSKI, E.G., 1971. Nitrate reductase assay in intactplant tissues. Biochem. Biophys. Res. Comm., 43:1274-1279. JOHNSON, D,A. e BROWN, R.W., 1977. Psychrometric analysis of turgor pressure response: a possible technique for evaluating plant water stress resistance. Crop Sci., 17:507-510. JUGENHEINER, R.W., 1976. Corn: improvement, seed production, and uses. John Wiley & Sons, New York-London, Sydney-Toronto. KEMBLE, A.R. e MacPHERSON, H.T.; 1954. Liberation of amino acids in perennial ryegrass during wilting. Biochem. J., 58: 46-50. KILEN, T.C. e ANDREW, R.H., 1969. Measurement of drought resistance in corn. Agron. J., 61:669-672. KLUGE, M., 1976. Carbon and nitrogen metabolism under water stress. In: Water and plant life. Ecological Studies Vol. 19, O.L. Lange; L. Kappen e E.D. Schulze (Ed.). SpringerVerlag. Berlin. Heidelberg, New York. KOEPPE, D.E.; MILLER, R.J. e BELL, D.T., 1973. Drought-affected mitochondrial processes as related to tissue and whole plant responses. Agron. J., 65:566-569. KOZLOWSKI, T.T. (Ed.), 1972. Water deficits and plant growth III. Plant responses and control of water balance. Academic Press, New York and London.194 KOZLOWSKI, T.T. (Ed.), 1976. Water deficits and plant growth. IV. Soil water measurement, plant responses, and breeding for drought resistance. Academic Press, New York, San Francisco, London. KRAMER, P.J., 1974. Fifty years of progress in water relations research. Plant Physiol., 54:463-471. KYLIN, A. e QUATRANO, R.S., 1975. Metabolic and biochemical aspects of salt tolerance. In: Plants in saline environments. Ecological studies. Vol 15. A. Poljakoff-Mayber e J. Gale (Ed.). Springer-Verlag, New York, Heidelberg, Berlin. LARCHER, W., 1975. Physiological plant ecology. Springer-Verlag, Berlin, Heidelberg, New York. LANGE, O.L.; KAPPEN, L. e SCHULZE, L.D. (Ed.)., 1976. Waterand plant life. Problems and modern approaches. Ecological studies. Vol 19. Springer-Verlag, Berlin, Heidelberg, New York. LARQUE-SAAVEDRA, A. e WAIN, R.L., 1974. ABA levels in relation to drought tolerance in varieties of Zea mays L., Nature, 251:716-717. LARSON, K.L., 1975. Drought injury and resistance of crop plants. In: Physiological aspects of dryland farming. U. S. Gupta (Ed.). Applied Science Publishers Ltd., England. LEVITT, J., 1972. Responses of plants to environmental stresses. Academic Press, New York, San Francisco, London. LUDLOW, M.M., 1976. Ecophysiology of C4 grasses. In: Water195 and plant life. Ecological studies. Vol 19. O.L. Lange; L. Kappen e L.D. Schulze (Ed.). Springer-Verlag, Berlin, Heidelberg, New York. MACHADO, R.C.R.; RENA, A.B. e VIEIRA, C., 1976. Efeito da desidrata??o osm?tica na germina??o de sementes de vinte cultivares de feij?o (Phaseolus vulgaris L.). Ceres, 23: 310- 320. MACNICOL, P.T., 1976. Rapid metabolic changes in the woulding response of leaf disc following excision. Plant Physiol., 57:80-84. MADRUGA, L.A.N. e RENA, A.B., 1977. Varia??es na concentra- ??o de prolina livre em folhas de plantas intactas de cinco cultivares de arroz (Oryza sativa L.) submetidas a desidrata??o. Ceres., 24:226-236. MAGNAVACA, R., 1976. Diretrizes do programa de pesquisa de milho do Centro National de Pesquisa de milho e sorgo. Ata da XXI Reuni?o T?cnica Anual do Milho e V do Sorgo Gran?fero. Instituto de Pesquisas Agron?micas, R.S. MARANVILLE, J.W. e PAULSEN, G.M., 1970. Alteration of carbohydrate composition of corn (Zea m ays L.) seedlings during moisture stress. Agron. J . , 62:605-608. MATTAS, R.E. e PAULI, A.W., 1965. Trends in nitrate reduction and nitrogen fractions in Young corn (Zea mays L.) plants during heat and moisture stress. Crop Sci., 5:181 - 184.196 McCUINNIES, J.W., 1960. Effects of moisture stress and temperature on germination of six range grasses. Agron. J., 52: 159-162. McMICHEL, B.L. e ELMORE, C.D., 1977. Proline accumulation in water stressed cotton leaves. Crop Sci., 17:905-908. McPHERSON, H.G. e BOYER, J.S., 1977. Regulation of grain yield by photosynthesis in maize subjected to a water deficiency. Agron. J., 69:714-718. MEASURES, J.C., 1975. Role of aminoacids in osmoregulation of non-halophilic bacteria. Nature, 257:398-400. MICHEL, B.E., 1970. Carbowax 6000 compared with mannitol as a suppressant of cucumber hypocotyl elongation. Plant Physiol, 45:507-509. MILLAN, A.J.; SILVA, J.C. e GALV?O, J.D., 1977a. Heran?a da velocidade de germina??o na variedade de milho "Piran?o". Ceres, 24: 278-288. MILLAN, A.J.; SILVA, J.C. e GALVAO, J.D., 1977b. Sele??o visando a toler?ncia ? salinidade causada por sulfato de am?- nio, na variedade de milho "Piran?o". Ceres, 24:386-393. MIRANDA, L.T. de., 1972. A caracter?stica "lat?ncia" do milho (Zea ma ys L.) e suas possibilidades no melhoramento. Tese apresentada ? Escola Superior de Agricultura "Luiz de Queiroz", da Universidade de S?o Paulo, para obten??o do t?tulo de Doutor. Piracicaba, S?o Paulo., 93p. MORILLA, C.; BOYER, J.S. e HAGEMAN, R.H., 1973. Nitrate reduc-197 tase activity-and polyribosomal content of corn (Zea mays L.) having low leaf water potentials. Plant. Physiol., 51: 817-824. NAYLOR, A.W., 1972. Water deficits and nitrogen metabolism. In: water deficits and plant growth. Vol III, T.T. Kozlowski (Ed.). Academic Press, New York and London. NIR, I.; POLJAKOFF-MAYBER, A. e KLEIN, S., 1970. The effect of water stress on the mitochondria of root cells. Plant Phy siol., 45:173-177. NOUR, A.M. e WEIBEL, D.E., 1978. Evaluation of root characteristics in grain sorgh.um. Agron. J., 70:217-218. PAL, U.R.; JOHNSON, R.R. e HAGEMAN, R.H., 1976. Nitrate reductase activity in heat (drought) tolerant and intolerant maize genotypes. Crop Sci., 16:775-780. P?LFI, G. e JU?SZ, J., 1971. The theoretical basis and practical application of a new method of selection for determining water deficiency in plants. Plant Soil, 34:503-507. PARKER, J., 1972. Protoplasmic resistence to water deficits. In: Water deficits and plant growth. Vol III. T.T. Kozlowski (Ed.). Academic Press. New York and London. PARMAR, M.T. e MOORE, R.P., 1968. Carbowax 6000, mannitol, and sodium chloride for simulating drought conditions in germination studies of corn (Zea mays L.) of strong and weak vigor. Agron. J., 60:192-195. PEARCE, R.B.; M0CK,J.J. e BAILEY, T.B., 1975. Rapid method198 for estimating leaf area per plant in maize. Crop Sci., l5: 691-694. PLAUT, Z., 1973. The effect of soil moisture tension and nitrogen supply on nitrate reduction and accumulationin wheat seedlings. Plant Soil, 38:81-94. PORTAS, C.A.M. e TAYLOR, H.M., 1976. Growth and survival of Young plant roots in dry soil. Soil Sci., 121:170-175. RADFORD, P.J., 1967. Growth analysis formulae their use and abuse. Crop Sci, 7:171-175. RAMOS, D.P.; CASTRO, A.F. de e CAMARGO, .M.N., 1973. Levantamento detalhado de solos da ?rea da Universidade Federal Rural do Rio de Janeiro. Pesq. agrop. bras., S?r. Agron., 8:1-27. RENA, A.B. e MASCIOTTI, G.Z., 1976. Efeito do deficit h?drico sobre o metabolismo do nitrog?nio e o crescimento de quatro cultivares de feij?o (Phaseolus vulgaris L.). Ceres , 23:288- 301. RICHARDS, L.A. e WADLEIGH, C.H., 1952. Soil water and plant growth. Agronomy. Vol II. B.T. Shaw, (Ed.) Academic Press Inc., publishers. New York. ROBINS, J.S. e DOMINGO, C.E., 1953. Some effects of severe soil moisture deficits at specific stages in corn. Agron.J., 45:612-621. RUSSEL, R.S., 1977. Plant root systems: their function and interaction with the soil. McGraw-Hill Book Company (UK) Limited, London.199 SHRRMA, M.L., 1973. Simulation of drought and its effect on germination of five pasture species. Agron. J., 65:982-987. SINGH, T.N.; PALEG, L.G. e ASPINALL, D., 1973. Stress metabolism III. Variations in response to water deficit in the barley plant. Aust. J. biol. Sci., 26:65-76. SLATYER, R.O., 1969. Physiological significance of internal water relations to crop yield. In: Physiological aspects of crop yield. J.D. Eastin; F.A. Haskins; C.Y. Sullivan e C. H. M. Van Bave1 (Ed.), Am. Soc. Agron., Crop Sci. Soc. Am. Madison, Wisconsin. SLAVIK, B. (Ed.), 1974. Methods of studying plant water relations. Ecological studies. Vol 9. Springer-Verlag. Berlin, Heidelberg, New York. STEWART, C.R.; MORRIS, C.L. e THOMPSON, F.L., 1966. Changes in aminoacid content of excised leaves during incubation. II. Role of sugar in the accumulation of proline in wilted leaves. Plant Physiol., 41:1585-1590. SULLIVAN, C.Y. e EASTIN, J.D., 1974. Plant physiological responses to water stress. Agric. Meteorol., 14:113-127. TEARE, I.D.; MANAM, R. e KANEMASU, E.T., 1974. Diurnal and seasonal trends in nitrate reductase activity in field grown sorghum plants. Agron. J., 66:733-736. TODD, G.W., 1972. Water deficits and enzymatic activity. In: Water deficits and plant growth. Vol III. T. T. Kozlowski (Ed.). Academic Press. New York and London.200 TRAVIS, R.L.; HUFFAKER, R.C. e KEY, J.L., 1970. Light-induced development of polyribosomes and the induction of nitrate reductase in corn leaves. Plant Physiol., 46:800-805. TROLL, W. e LINDSLEY, J., 1955. A photometric method for the determination of proline. J. biol. Chem., 215:655-660. TURNER, N.C., 1974. Stomatal behavior and water status of maize, sorghum and tobacco under field. conditions. Plant Physiol., 53:360-365. VIEIRA DA SILVA, J., 1976. Water stress, ultrastructure and enzimatic activity. In: water and plant life. Ecological studies. Vol 19. O.L. Lange, L. Kappen e E.D. Schulze (Ed.) Springer-Verlag. Berlin Heidelberg, New York. VIETS, Jr., F.G., 1971. Effective drought control for successful dryland agriculture. In: Drought injury and resistence in crops. K.L. Larson e J.D. Eastin (Ed.). Crop Sci. Soc. Am. Special publication number 2. Madison, Wisconsin. WALDREN, R.P. e TEAE, I.D., 1974. Free proline accumulation in drought-stressed plants under laboratory conditions. Plant Soil, 40:689-692. WILLIAMS, T.V.; SNELL, R.S. e ELLIS, J.F., 1967. Methods of measuring drought tolerance in corn. Crop Sci., 7:179-182. WINTER, E.J., 1974. Water, soil and the plant. The MacMillan Press Ltd., London. WOLF, J.M., 1975. Water constraints to corn productivity in Central Brazil. Ph.D. Thesis. Cornell University, Ithaca,201 New York, 199p. WRIGHT, L.N., 1904. Drouth tolerance - Program controlled environmental evaluation among range grass genera and species. Crop Sci., 4:472-474. WRIGHT, L.N., 1971. Drought influence on germination and seedling emergence. In: Drought injury and resistance in crops. K.L. Larson e J.D. Eastin (Ed.). Crop Sci. Soc. Am. Special publication number 2. Madison, Wisconsin. WRIGHT, L.; WRENCH, P.; HINDE, R.W. e BRADY, C.J., 1977. Proline accumulation in tubers of Jerusalem artichoke. Aust. J. Plant Physiol., 4:51-60. YEM, E.W. e WILLIS, A.J., 1954. The estimation of carbohydrates in plant extracts by antrone. Biochem. J., 57: 508-514. YEM, E.W. e COCKING, E.C., 1955. The determination of aminoacids with ninhydrin. Analyst, 80:209-213. YOUNIS, M.A.; STICKLER, F.C. e SORENSEN, E.L., 1963. Reactions of seven alfafa varieties under simulated moisture stresses in the seedling stage. Agron. J., 55:177-182. YOUNIS, M.A.; PAULI, A.W.; MITCHELL, H.L. e STICLER, F. C., 1965. Temperature and its interaction with light and moisture in nitrogen metabolism of corn (Zea mays L.) seedlings. Crop Sci., 5:321-326. ZIESERL, J.F.; RIVENBARK, W.L. e HAGEMAN, R.H., 1963. Nitrate reductase activity protein content, and yield of four maize hybrids at varying plant populations. Crop Sci., 3:27- 32

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