Original scientific paper

THE RETATIONSHIP BETWEEN RELATIVE WATER CONTENT (r. w. c.) AND NUMBER AND SIZE OF FLAG LEAF STOMATA IN WHEAT - T. AESTIVUM SSP VULGAR.

Marijan Jošt ; Poljoprivredni institut Zagreb, OOUR-Institut za oplemenjivanje i proizvodnju bilja
Milica Glatki -Jošt ; Poljoprivredni institut Zagreb, OOUR-Institut za oplemenjivanje i proizvodnju bilja

Abstract

Relative water content (r. w. c.) is an index of dehidration avoidance. If the r. w. c. of one plant remains essentially constant during anought and that of the second plant rises markedly, this usually reveals a greater drought avoidance in the former (Levitt 1972.) Nothwithstanding an abundant supply of soil with moisture, daily wather deficit might occur in plant, associated with low relative humidity of air, great solar radiation and wind. Due to intensive transpriration, quantity of wather disimissed from plant in such a case would surpass the water quantity absorbed from the soil (Aston 1970). Thus, speed of giving off water vapour to atmospher will depend upon leaf anatomy, and speed of compensating water loss will,the dependent upon root absorbing capacity. In the present work varietal differences are considered, - in the r. w. c. of wheat flag leaf and in some characters of leaf anatomy (total number of leaf stomata, frequency of stomata, and size of stomatal pore) - as well as the relationship between the r. w. c. and the characters of leaf, anatomy studied. At field conditions, near Zagreb, one year experiment was concrueted, using 10 genotypes of winter wheat, divergent for characters of leaf anatomy, and selected on the basis of previous studies (Jošt et al. 1972). The r. w. c. of flag leaf was determined at two different weather situations and results ,are diagrammed in Fig. 1. Difference (D) in the r. w. c. varied from 0,70 - 4,25%, depending on variety (Tab. 1). The greatest difference was displayed by the branched wheat line Ramifere aristatum 86/68 and it follows that this line has the smallest ability for avoiding dehydration. Characteristics of leaf anatomy (total number of flag leaf stomata, frequency of stomata, and size of stomatal pore) for the varieties tested are presented in Tab. 1. It can be seen that the line of branched wheat mentioned, exceeded others in the total number of leaf stomata, and large size of its stomatal poresis recorded, too. From the correlations calculated (Table 2) it is evident that plant ability for avoiding dehidration is affected by all the anatomy studied (multiple correlation coefficient R =0.81) i.e.by the total number of leaf stomata in the first place, then by pore size while stomatal frequency has the smallest effect on dehydration avoidance(linear and partial correlation coefficients).

Keywords

Hrčak ID:

165366

URI

https://hrcak.srce.hr/165366

Publication date:

30.7.1975.

Article data in other languages: croatian

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