Variability and Synchronism of Leaf Appearance and Leaf Elongation Rates of Eleven Contrasting Rice Genotypes

Rohilyn B. Egle¹, Abigail J. Domingo², Crisanta Bueno², Antonio C. Laurena¹, Edna A. Aguilar¹, Pompe Sta. Cruz¹, Benoit Clerget^2,3*

¹Crop Science Cluster, College of Agriculture, University of the Philippines Los Baños, Laguna, Philippines.
²IRRI (International Rice Research Institute), Los Baños, Laguna, Philippines.
³CIRAD (Agricultural Research Centre for International Development), UMR AGAP, Montpellier, France.

DOI: 10.4236/as.2015.610116                

Abstract

Leaf appearance and leaf elongation rates in rice play an essential role in determining the development of the plants’ architecture which affects their adaptability to varying environments. This study aimed to characterize the rates of leaf appearance and elongation on all leaves of the main culms of rice plants for 11 contrasting varieties and to determine if the decrease in the leaf appearance rate was related to a simultaneous decrease in the rate of leaf elongation. Forty four 13-L pots were sown with one plant from one genotype and laid out in 4 randomized complete blocks. The experiment, conducted inside a greenhouse, was repeated twice. The increase in length of the leaves expanding on the main stems was monitored daily until flag leaf. Data were used to estimate the rates of leaf appearance and leaf elongation. Significant variability in the rate of leaf appearance, rate of leaf elongation, and leaf length was found across varieties. The kinetics of leaf appearance had linear phases intermediated by a curvilinear phase, without sharp changes in the phyllochron duration. Maximal leaf elongation rate (LER) of all genotypes (except for one) increased linearly with leaf rank until it reached its maximum value at leaf 8 to 10 (11 - 12 for Azucena) where it stabilized before decreasing linearly with leaf rank for the last leaves. Finally, both rates of leaf appearance and leaf elongation evolved with time more smoothly than expected so no sharp decrease in LER occurred at the time of the decrease in leaf appearance rate of the last leaves. However, the trilinear model fits the data well enough to remain useful in efficiently comparing the leaf appearance kinetics of contrasting varieties.

Keywords

Phyllochron, Development, Flowering, Photoperiod, Oryza sativa L.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Rickman, R.W. and Klepper, B.L. (1995) The Phyllochron: Where Do We Go in the Future? Crop Science, 35, 44-49. http://dx.doi.org/10.2135/cropsci1995.0011183X003500010008x
[2]	Wilhelm, W.W. and McMaster, G.S. (1995) Importance of the Phyllochron in Studying Development and Growth in Grasses. Crop Science, 35, 1-3. http://dx.doi.org/10.2135/cropsci1995.0011183X003500010001x
[3]	McMaster, G.S. (2005) Phytomers, Phyllochrons, Phenology and Temperate Cereal Development. Journal of Agricultural Science, 143, 137-150. http://dx.doi.org/10.1017/S0021859605005083
[4]	Nemoto, K., Morita, S. and Baba, T. (1995) Shoot and Root Development in Rice Related to Phyllochron. Crop Science, 35, 24-29. http://dx.doi.org/10.2135/cropsci1995.0011183X003500010005x
[5]	Clerget, B., Bueno, C., Quilty, J.R., Correa Jr., T.Q. and Sandro, J. (2014) Modifications in Development and Growth of a Dual-Adapted Tropical Rice Variety Grown as Either a Flooded or an Aerobic Crop. Field Crops Research, 155, 134-143. http://dx.doi.org/10.1016/j.fcr.2013.09.013
[6]	Yoshida, S. (1981) Fundamentals of Rice Crop Science. The International Rice Research Institute, Los Baños.
[7]	Parent, B., Conejero, G. and Tardieu, F. (2009) Spatial and Temporal Analysis of Non-Steady Elongation of Rice Leaves. Plant, Cell and Environment, 32, 1561-1572. http://dx.doi.org/10.1111/j.1365-3040.2009.02020.x
[8]	Fournier, C., Durand, J.L., Ljutovac, S., Schaüfele, R., Gastal, F. and Andrieu, B. (2005) A Functional-Structured Model of Elongation of the Grass Leaf and Its Relationships with the Phyllochron. New Phytologist, 166, 881-894. http://dx.doi.org/10.1111/j.1469-8137.2005.01371.x
[9]	Egle, R.B. (2014) Synchronism of Leaf Development and Leaf Elongation Rates of Contrasting Rice (Oryza sativa L.) Genotypes. M.Sc. Thesis, University of the Philippines Los Baños.
[10]	Clerget, B. and Bueno, C. (2013) The Effect of Aerobic Soil Conditions, Soil Volume and Sowing Date on the Development of Four Tropical Rice Varieties Grown in the Greenhouse. Functional Plant Biology, 40, 79-88. http://dx.doi.org/10.1071/FP12194
[11]	Streck, N.A., Bosco, L.C. and Lago, I. (2008) Simulating Leaf Appearance in Rice. Agronomy Journal, 100, 490-501. http://dx.doi.org/10.2134/agronj2007.0156
[12]	Yin, X. and Kropff, M.J. (1996) The Effect of Temperature on Leaf Appearance in Rice. Annals of Botany, 77, 215-221. http://dx.doi.org/10.1006/anbo.1996.0025
[13]	Haun, J.R. (1973) Visual Quantification of Wheat Development. Agronomy Journal, 66, 116-119. http://dx.doi.org/10.2134/agronj1973.00021962006500010035x
[14]	SAS (2008) SAS Online® 9.2. SAS Institute Inc., Cary, NC.
[15]	Wald-Wolfowitz (or Runs) Test for Randomness, Knowledge Base/Samples & SAS Notes. http://support.sas.com/kb/33/092.html
[16]	Fukai, S. (1999) Phenology in Rainfed Lowland Rice. Field Crops Research, 64, 51-60. http://dx.doi.org/10.1016/S0378-4290(99)00050-7
[17]	Vergara, B.S. and Chang, T.T. (1985) The Flowering Response of the Rice Plant to Photoperiod: A Review of the Literature. 4th Edition, International Rice Research Institute, Los Baños.
[18]	Kawakata, T. and Yajima, M. (1995) Modeling Flowering Time of Rice Plants under Natural Photoperiod and Constant Air-Temperature. Agronomy Journal, 87, 393-396. http://dx.doi.org/10.2134/agronj1995.00021962008700030001x
[19]	Sié, M., Dingkuhn, M., Wopereis, M.C.S. and Miezan, K.M. (1988) Rice Crop Duration and Leaf Appearance Rate in a Variable Thermal Environment: I. Development of an Empirically Based Model. Field Crops Research, 57, 1-13. http://dx.doi.org/10.1016/S0378-4290(97)00110-X
[20]	Clerget, B., Dingkuhn, M., Gozé, E., Rattunde, H.F.W. and Ney, B. (2008) Variability of Phyllochron, Plastochron and Rate of Increase in Height in Photoperiod-Sensitive Sorghum Varieties. Annals of Botany, 101, 579-594. http://dx.doi.org/10.1093/aob/mcm327
[21]	Lafarge, T. and Tardieu, F. (2002) A Model Co-Ordinating the Elongation of All Leaves of a Sorghum Cultivar Was Applied to Both Mediterranean and Sahelian Conditions. Journal of Experimental Botany, 53, 715-725. http://dx.doi.org/10.1093/jexbot/53.369.715