Effect of Plant Density on Allometric Relationships between Plant Height and Vegetative Traits of Wheat

Document Type : Research Article

Authors

• B Zafari ghalehrodkhani
• A Soltani
• E Zeinali
• B Kamkar
• M Firozfard

Gorgan University of Agricultural Sciences and Natural Resources

10.22067/gsc.v15i2.46029

Abstract

Introduction Crop models are the most important parts of ecological models. These models could provide the possibility of crop systems prediction in addition to increase the understanding of their performance. Allometric relationships of plants show the changes of growth of one part in comparison to the other parts of the plant. Determining the appropriate plant density in crops, especially wheat has the high importance which affects some characteristics such as yield and yield components. This effect varies between different stages of plant growth.

Materials and Methods This research has been done in research station of Gorgan University of Agricultural Sciences and Natural Resources (37 45N, 54 30E and 120m asl) in the growing season of 2012-13. The experiment was conducted in a factorial experiment with randomized complete block design with four replications as base. Treatments consisted of two wheat cultivars (Koohdasht and Morvarid) and 7 plant densities (50, 100, 200, 350, 500, 650, 800 seed.m2). Each replication consisted of 14 plots and each plot had 10 rows with length of 5 m, width of 2 m and a row spacing of 20 cm. Plot distances from each other was 40 cm and block distances was 1 m to each other. Measurements were done from tillering to the end of the growing every 7 to 10 days (depending on weather conditions). Cumulative thermal units were calculated using GDD_Calc program. Power model and non-liner segmented regression model were used to describe allometric relationships.

Results and Discussion In fitting allometric equations related to plant height, results showed that plant height in wheat starts from emergence and reaches the maximum in the anthesis stage and then remains constant. Hence, fitting equations were done to find allometric relations of wheat plant height and coefficient of 0.94 and root mean square error between 6.80 and 5.16 showed that the equation could well describe the height of plant during the growing season. Checking coefficients showed that there was no significant differences between a coefficient but significant differences was investigated in b coefficient and X0 coefficient. The analysis of the relationship between plant height and the number of leaves in main stem showed a significant effect according to b coefficient with coefficient of determination of 0.92, in different densities. Coefficient of determination values greater than 0.97 indicated a strong relationship between plant height and shoot dry weight, but the analysis showed no significant effect in terms of a (plant height when shoot dry weight is 1 gr) and b coefficients. In addition, regarding the relationship between the height and total dry weight of vegetative parts in different plant density, coefficient of determination values greater than 0.97 and ranges of root mean square error between 4.86 and 9.119, belong to the plant densities of 50 and 800, respectively, which showed a very good correlation between the height and the total dry weight of vegetative parts. The a coefficient (plant height when total dry weight is 1 gr) had significant difference and decrees about 0.0036 unit according to each plant more dense but for b coefficient, there was no significant difference.
Conclusions In general, the results revealed that plant height has significant correlation with the number of leaves in main stem, shoot dry weight and total dry weight of vegetative parts by coefficient of determination 0.93, 0.97 and 0.96, respectively. In addition, the correlation coefficient for producing leaves in main stem was 0.93.

Keywords

• Allometric
• Plant height
• Plant density
• Variety
• Vegetative traits

20.1001.1.20081472.1396.15.2.5.1

---

References

1. Akram-Ghaderi, F., and Soltani, A. 2007. Leaf area relationships to plant vegetative characteristics in cotton in cotton (Gossypium hirsutum L.) grown in a temperate sub-humid environment. Journal of Plant Production 1: 63-71.

2. Bakhshandeh, A. 2011. Assessment of allometric relations in wheat. Master Thesis Gorgan University of Agricultural Sciences and Natural Resources. 104 p.

3. Bakhshandeh, A., Soltani, A., and Ghadiriyan, R. 2011. ACC PAR measurements of leaf area index using wheat. Journal of Plant Production 18 (4): 97-102 P.

4. Bakhshandeh, A., Soltani, A., Zeynali, E., Kalatearabi, M., and Ghadiriyan, R. 2011. Assessment of allometric relations of leaf and vegetative traits in bread wheat and durum. Iranian Journal of Crop Sciences 13(4): 642-657 P.

5. Bakhshandeh, E., Soltani, A. Zeinali, E., and Kallate-Arabi, M. 2010. Prediction of plant height byallometric relationships in field-grown wheat. Ceareal Res Commu 40 (3): 487-496.

6. Bromandrezazadeh Z., Rezvanimoghadam, P., and Rashedmohasel, M.H. 2005. Effect of planting date and plant density on yield components and morphological characteristics. National Conference on the Sustainable Development of Medicinal Plants. Mashhad (Abs).

7. Cao, W., and Mass, D. 1989. Wild oat competition with spring wheat: Plant density effects. Weed Sci. 33: 178-181.

8. Cosenss, R.D., Weaver, S. E. Martin, T. D. Blair, A. M., and Wilson, J. 1991. Dynamic of competition between wild oat (Avena fatua L.) and winter cereals. Weed Res. 37: 203-210.

9. Han, J.R. 1973. Visual qualification of wheat development. Agron. J. 65:116-119.

10. Hodges, T., and Evans, D.W. 1990. Light interception model for estimating the effects of row spacing on plant competition in maize. J.Prod. Agric. 3:190-195.

11. Nagashima, H., and Terashima, I. 1995. Relationships between height, diameter and weight distributions of Chenopodium album plants in stands: Effects of dimension and allometry. Ann. Bot. 75: 181-188.

12. Nazarigolshan, A., Seyfzadeh, S., Moradimoghadam, A., and Taherkhani, T. 2010. The effect of plant density on some agronomic traits in sunflower under limited irrigation conditions. Journal of Crop Science 7: 49-63.

13. Niklas, K.J. 1994. Plant allometry, the scaling of form and process. Chicago: University of Chicago press. 81: 339-344.

14. Noshkam, A., Mazaheri, D., Hosieni, M.B., and Mirabzadeh, M. 2009. Effect of plant density and sowing date on yield and quality of forage and seed yield of Egyptian clover (Trifolium alexandrinum L.). Iranian Journal of Crop Sciences 11 (4): 325-336.

15. Partovkazemi, A., Delkhosh, B., and Mohseni, M. 2011. Effect of tillage practices and plant density on yield and yield components of three corn hybrids. The new findings Agriculture 5(3): 221-230.

16. Peters, N. C. B., and Wilson, B. J. 1986. Some studies on the competition between (Avena fatua L.) and spring barely.II. Variation of A.fatua emergence and development and its influence on crop yield. Weed Res. 23: 305-311.

17. Porreza, J., Soltani, A., Rahemi, A., Galeshi, S., and Zeynali, A. 2007. Allometric relationships between plant height and growth traits in pea plants. Journal of Agricultural Sciences and Nat Res. 14 (5): 178-190.

18. Porreza, J., Soltani, A., Rahemi, A., Galeshi, S., and Zeynali, A. 2007. Determination of dry matter distribution among different organs in chickpea. Journal of Agricultural Sciences and Natural Resources 14(5): 178-190.

19. Rahemi-karizaki, A. 2005. Predicting interception and use of solar radiation in chickpea. Thesis of M.Sc. Gorgan Uni.Agric Sci. Natur Resour. 89 p. (in Persian).

20. Rahmani, A., Khavarikhorasani, S., and Nabavikalat, M. 2009. Effect of planting date and plant density on yield, yield components and some agronomic characteristics of corn salad varietie KSC403su. Journal of Agricultural Seed and Plant. 2-25(4): 449-463.

21. Reddy, V.R., Pachepsky, Y.A., and Whislers, F.D. 1998. Allometric relationships in field-grown soybean. Annals of Botany, 82: 125-131.

22. Romas, J.M., Gariadel Moral, L.F., and Reclade, L. 1983. Dry matter and leaf area relationship in winter barley. Agron. J. 75: 308-310.

23. Soltani, A. 2009. Mathematical modeling in crop plants. Press Scientific Information Database Mashhad. P 175.

24. Soltani, A., 2006. Review of the application of statistical techniques in agricultural research. Press Scientific Information Database Mashhad. P 74.

25. Soltani, A., and Hoogenboom, G. 2003. A statistical comparison of stochastic weather generators WGEN and SIMMETEO. Climate Res. 24: 215-230.

26. Van Ittersum, M.K., and Donatelli, M. 2003. Modeling cropping systems highlights of the symposium and preface to the special issues. Eur. J. Agron. 18: 187-197.