Desenvolvimento e produtividade de algodoeiros sob efeito de reguladores vegetais

In this work effects of plant regulators on cotton Gossypium hirsutum L. cv. IAC-17 were studied, through growth analysis and productivity measures in plants subjected to different dosages of plant regulators applied at various stages of growth. To discover the growth, production and agronomic characteristics of the cotton plant and the technological characteristics of the fibers, under the effect of plant regulators, an experiment, under field conditions was carried out in Piracicaba (SP) on the 1978/79 crop. Cotton was treated with 84, 167 and 250 ppm DPC; 250, 350 and 450 ppm CCC and 1670, 3340 and 6680 ppm CEPA, at respectively 5, 65 and 143 days after germination. The results show that DPC and CCC tended to reduce plant height and crown diameter. DPC applications did not affect growth analysis parameters while 250 ppm CCC reduced foliar area and the" dry matter weight of cotton. The leaf area index was reduced during 28 days, with 250 ppm and 350 ppm applications; the lowest concentrations reduced the photosynthetic efficiency of the plants and the highest concentration of CEPA and CCC tended to reduce the number of boll number of seeds and wool weight. CCC 350 ppm apparently increased the average bool weight while CEPA 6680 ppm tended to reduce it. With each treatment the seed weight and fiber percentage sampled in 50 g of seed as well as the weight of seeds were not affected by CCC, DPC and CEPA applications. The technological characteristics of the fibers were not affected by plant regulators.

[1]  L. P. Cruz,et al.  Efeitos do cloreto de mepiquat empregado como fitorregulador sobre algodoeiro herbáceo (Gossypium hirsutum L."IAC 16") , 1982 .

[2]  H. Gausman,et al.  Increase of cold tolerance in cotton plant (Gossypium hirsutum L.) by mepiquat chloride , 1982 .

[3]  J. T. Cothren.  Pix - a cotton growth regulant , 1979 .

[4]  P. Castro,et al.  Ação de reguladores vegetais na germinação do algodoeiro (Gossypium hirsutum L. cv. 'IAC - 17') , 1978 .

[5]  N. Sabino,et al.  Efeitos da densidade de plantio e da aplicação de CCC, em algodoeiro , 1977 .

[6]  G. Guinn.  Nutritional Stress and Ethylene Evolution by Young Cotton Bolls 1 , 1976 .

[7]  J. Bhatt.  Differential response of cotton to cycocel plant growth regulant , 1975 .

[8]  P. Castro,et al.  Efeitos de giberelinas no desenvolvimento do algodoeiro (Gossypium hirsutum L. cv.'IAC-RM3') , 1975 .

[9]  N. Fonseca,et al.  Efeitos da salinidade em algodoeiros tratados com produtos químicos , 1975 .

[10]  M. Sousa,et al.  Efeitos do ccc no desenvolvimento do algodoeiro (Gossypium hirsutum L. cv. 'IAC-RM3') , 1975 .

[11]  P. Castro.  Análise de crescimento do amendoinzeiro (Arachis hypogaea L.) com relação à infestação de pragas , 1974 .

[12]  M. Zur,et al.  Effect of Time and Rate of Application of Two Growth Retardants on Growth, Flowering, and Yield of Upland Cotton 1 , 1973 .

[13]  P. Morgan,et al.  Ethylene, a regulator of young fruit abscission. , 1973, Plant physiology.

[14]  C. Lindley.  A Review of Some Practical Uses of Cycocel Plant Growth Regulant , 1973 .

[15]  M. S. Kairon,et al.  Preliminary studies on the effect of Cycocel on cotton. , 1970 .

[16]  D. Watson,et al.  Photosynthesis in Crop Profiles, Measured by Phytometers , 1968 .

[17]  F. El-Baz,et al.  Effect of CCC on Cotton Plants , 1968 .

[18]  E. Humphries,et al.  Effects of growth regulators, CCC and B9, on some potato varieties , 1967 .

[19]  Rw King,et al.  Photosynthesis in Artificial Communities of Wheat, Lucerne, and Subterranean Clover Plants , 1967 .

[20]  E. Humphries,et al.  Modification of growth habit of Majestic potato by growth regulators applied at different times , 1966 .

[21]  E. Humphries,et al.  A growth study of sugar beet treated with gibberellic acid and (2‐chloroethyl)trimethylammonium chloride (CCC) , 1965 .

[22]  T. Saeki,et al.  Photosynthesis in Artificial Communities of Cotton Plants in Relation to Leaf Area I. Experiments with Progressive Defoliation of Mature Plants , 1965 .

[23]  L. Paleg,et al.  Physiological effects of gibberellic acid. 8. Growth retardants on barley endosperm. , 1965, Plant physiology.

[24]  Robert O. Thomas.  Effects of Application Timing and Concentration of 2-Chloroethyl Trimethylammonium Chloride on Plant Size and Fruiting Responses of Cotton 1 , 1964 .

[25]  H. Cathey.  Physiology of Growth Retarding Chemicals , 1964 .

[26]  E. Humphries.  Effects of (2 Chloro-Ethyl) Trimethlammonium Chloride on Plant Growth, Leaf Area, and Net Assimilation Rate , 1963 .

[27]  D. Watson,et al.  Analysis of Growth and Yield of Winter and Spring Wheats , 1963 .

[28]  D. J. Watson,et al.  The Dependence of Net Assimilation Rate on Leaf-area Index , 1958 .

[29]  C. Donald,et al.  The growth of swards of subterranean clover with particular reference to leaf area , 1958 .

[30]  R. W. Brougham.  Effect of intensity of defoliation on regrowth of pasture , 1956 .

[31]  F. M. Eaton.  Physiology of the Cotton Plant , 1955 .

[32]  F. Addicott.  Physiology of abscission , 1955 .

[33]  L. A. Derscheid.  Physiological and Morphological Responses of Barley to 2,4-Dichlorophenoxyacetic Acid. , 1952, Plant physiology.

[34]  L. M. Josephson.  Effect of Maleic Hydrazide in Delaying Flowering in Corn2 , 1951 .

[35]  G. E. Blackman,et al.  Physiological and Ecological Studies in the Analysis of Plant Environment VII. An Analysis of the Differential Effects of Light Intensity on the Net Assimilation Rate, Leaf-Area Ratio, and Relative Growth Rate of Different Species , 1951 .

[36]  K. Thimann,et al.  The effect of auxin on flower initiation. , 1949, American journal of botany.

[37]  A. A. Dunlap.  Fruiting and Shedding of Cotton in Relation to Light and Other Limiting Factors. , 1945 .