Document Type : Research Article

Authors

1 Zanjan University

2 Qazvin Agricultural and Natural Resources Research and Education Center

Abstract

Introduction: Distribution of photosynthetic substances between vegetative and reproductive parts is influenced by the environmental factors as well as plant nutrition status. Therefore, application of nutrient substances (such as chelated magnesium sulfate and salicylic acid combination) can influence the distribution of photosynthetic substances which in turn result in changes in allocation of photo-assimilates between vegetative and reproductive parts. Since the investigation of partitioning of photo- assimilates is complex and the interpretation of treatments effects on partitioning of substances is difficult in garden plants, this examination has been focused on external application of nutritional treatments on different organs growth by comparing the effects of salicylic acid and chelated magnesium sulfate on the allocation of photo- assimilates.
Materials and Methods: This experiment was performed in a commercial 10-year old orchard of Qazvin in 2013. Initially, 60 uniform pears (cv. Louise Bonne) which were infected to fire blight disease were selected. Before treatment imposing, agronomic practices such as removing and pruning infected shoots were applied. Treatments were combination of salicylic acid and chelated magnesium sulfate at different levels, which were applied on foliage under the conditions of neutral pollution to fire blight. In the present research, vegetative parameters (current shoot growth, leaf weight, leaf area, relative water content and so on) and reproductive parameters (length: diameter ratio and density of fruit and so on) were measured.
The fully expanded leaves were collected randomly from each replicate. After washing the samples were weighed and these values referred to as initial readings (fresh weight). Then, the leaf samples were placed in distilled water for 24 h in the dark at room temperature. The turgid leaves were blotted dry and weighed (saturation weight). After weighing, the material was oven-dried at 70 °C for 24 h. Relative water content (RWC) of the leaves was appraised as described by Ritchie and Nguyen (19) using the following formula:
RWC (%) = [(f. wt. – d. wt.) / (t. wt. – d. wt.)] × 100
Where f. wt, d. wt and t. wt are fresh weight, dry weight and turgid weight, respectively.
Diameter and length of fruit were measured by nondestructive method (on the tree) and by using digital caliper in the places of maximum length and maximum width diameters, and length: diameter ratio from the division of these two parameters. Fruit weight was estimated by digital scale (0.01 g) and its volume by the difference of the water level of scaled column, and then fruit density was calculated by using formula d=M/V.
In order to estimate the parameters of leaf area, specific leaf area and specific leaf weight, leaf area meter and oven were used. To evaluate the effect of the treatments on decrease or increase current shoot growth, measuring shoot length was reported by tape measure according to centimeter.
Results and Discussion: The results indicated that the most amount of specific leaf weight was allocated in chelated magnesium sulfate (0.5 and 0.7 g: 1000 ml) treatments and the least amount was belonged to the control group. The extent of changes in leaf area was between 28.17 to 44.33 cm2, were recorded to control group (without water) and salicylic acid (0.1 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The minimum and maximum of specific leaf area were ranged between 44.14 to 59.40 cm2 and belonged to control group (without water) and salicylic acid (0.1 g: 1000 ml), respectively. The most current shoot growth was observed in control group (without water) and the least quantity was in chelated magnesium sulfate (0.5 g: 1000 ml). The minimum and maximum of fresh weight of leaf was changeable between 1.513 to 1.94 g were recorded to control group and salicylic acid (0.1 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The most and the least content of leaf relative water were observed to salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.5 g: 1000 ml) and salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml), respectively. The extent of changes in fruit specific gravity was changeable between 0.72 to 0.97 g to cm3. The maximum amount of fruit specific gravity was seen in salicylic acid (0.5 g: 1000 ml) plus chelated magnesium sulfate (0.7 g: 1000 ml) and the minimum amount was in salicylic acid (0.5 g: 1000 ml) treatment. The conformity of the maximum current shoot growth and leaf fresh weight with the minimum leaf dry weight, leaf area, specific leaf area and specific leaf weight to control group and control group (without water) can declare the effect of treatment substances on the allocating manner of substances in different organs in plants and its stimulating effect on vegetative indexes that is not observable in the lack of treatment substances. The allocation of the most fruit specific gravity and also the least leaf relative water content and the least fruit length: diameter ratio to salicylic acid (0.5 g: 1000 ml) and chelated magnesium sulfate (0.7 g: 1000 ml) can confirm the opposit relation among these parameters in the way of substances allocation and the effect of above treatment on this opposit relation. Denser fruits have fewer growth rather than types with the more blank space and receive a more carbohydrate from the tree rather than their weight. The decrease of relative water content of leaf can also be explained in the direction of the more absorption of carbohydrate by fruit as a strong sink. In other words, the existence of fruit as a strong sink in favorable conditions for photosynthesis (with paying attention to the high vegetative indexes) can prevent gathering water in chloroplast and cause an increase of fruit specific gravity.
Also, the allocation of the most specific leaf weight and the least fruit length: diameter ratio and the least current shoot growth to chelated magnesium sulfate (0.5 g: 1000 ml) express the positive role of sulfur in aforesaid concentration on stimulating leaf growth and its negative role in stimulating growth of shoot and fruit that somehow points on the effect of treatment substances on the allocation of substances (elaborate sap) to different organs. The sulfur compounds can cause preventing gibberellin synthesis and the decrease of internode length, like other growth retardants.
The maximum fruit length: diameter ratio was belonged to salicylic acid (0.1 g: 1000 ml) and chelated magnesium sulfate (0.7 g: 1000 ml). Salicylic acid (0.1 g: 1000 ml) treatment induced maximum amounts of fruit length and diameter to itself that confirms the positive role of salicylic acid in stimulating growth in stress conditions (biotic stress derived from Erwinia amylovora). The significant negative correlation (p

Keywords

1- Adel M., Adel M., Amiri M. E., Nejatian M. A. and Davodi A. 2013. The examination of the effect of spray of edetated magnesium sulfate and salsylic acid on the shoot Fire blight of pear (cv. Louise Bonne). Articles Abstract of the 8th Agricultural Science Congress of Iran. Hamadan. Page 427 (in Persian with English abstract)
2- Adel M., Amiri M. E. and Adel M. 2014. Influence of spray with salicylic acid and coriander extract on shoot Fire Blight and fruit quality in pears (cv. Louise Bonne). New Issues Congress. Karaj. (in Persian)
3- Adel M. and Adel M. 2017. Breeding Plantation Tree Crops: Temperate Species (translation). The first edition. University Jihad Publications.
4- Arias M., Carbonell J. and Agusti M. 2005. Endogenous free polyamines and their role in fruit set of low and high parthenocarpic ability citrus cultivars. Plant Physiology. 162: 845 -853.
5- Barker A.V. and Pilbeam D.J. 1937. Handbook of plant nutrition. CRC-Taylor and Francis Group. New York. 613 p.
6- Biasi R., Bagni N. and Costa G. 1988. Endogenous polyamines in apple and their relationship to fruit set and fruit growth. Physiologia Plantarum. 73 (2): 201–205.
7- Faust M. 2001. Physiology of Fruit Trees of Temperate Regions. Translation: Gholami, M. and Kimiaei Talab, M. R. Boo Ali Sina Publications. Hamadan. 350 pp.
8- Gopi R., Sridharon R., Somasundaram R., Alagulakshmanan G.M., and Panneerselvam R. 2005. Growth and photosynthetic characteristics as affected by triazols in Amorphophallus campanulatus. General and Applied Plant Physiology. 31: 171-180.
9- Hayat S. and Ahmad A. 2007. Salicylic acid a plant hormone. Springer. India. 410 pp.
10- Hoseinzadeh Gashti E., Isfahani M., Asghari J., Sapharzadeh Vishkaii M. T. and Rabiei B. 2009. The effect of consumption of sulfur fertilizer on the growth and yield indexes of peanut (Arachis hypogaea L.). Journal of Agricultural Science and Technology. 48: 27- 38. (in Persian)
11- Jalili Marandi R. and Haji Taghi Loo R. 2003. The laboratory of post-harvest physiology. Oroomiyeh University Publications. Oroomiyeh. 12. (in Persian)
12- Kakkar R.K. and Rai V.K. 1993. Plant polyamines in flowering and fruit ripening. Phytochemistry. 33: 1281-1288.
13- Malik A.U. and Singh Z. 2004. Endogenous free polyamines of mangos in relation to development and ripening. Journal of the American Society for Horticultural Science. 129 (3): 280-286.
14- Manthe B., Schulz M., Schnabl H. 1992. Effects of salicylic acid on growth and stomatal movements of Vicia faba L.: evidence for salicylic acid metabolization. Journal Chemical Ecology. 18: 1525–1539.
15- Mazaheri Tirani M., Kalantari Kh. M., and Hasibi N. 2008. The study of the interactive effects of ethylene and salicylic acid on induction of oxidative stress and the mechanisms of tolerance in Brassica napus L. Iran Journal of Biology. 21 (3): 421-432.
16- Metwally A., Finkemeier I., Georgi M., Dietz K.J. 2003. Salicylic acid alleviates the cadmium toxicity in Barley seedling. Plant Physiology. 132: 272-281.
17- Mishra S.N. and A.P. Singh. 1989. Studies on sulphur and phosphorus availability and uptake by groundnut. Legume Research. 12(4): 160-164.
18- Nazardin M.R.A., Fauzi R.M., and Tsan F.Y. 2007. Effects of paclobutrazol on the growth and anatomy of stems and leaves of Syzygium campanulatum. Tropical Forest Science. 19: 86-91.
19- Ritchie S.W. and Nguyen H.T. 1990. Leaf water content and gas exchange parameters of two wheat genotypes differing in drought resistance. Crop Science. 30: 105-111.
20- Sapharzadeh Vishkaii M. N. 1998. The effect of sulfur on the growth and yield of peanut. M.Sc. Thesis, Isfahan University, Isfahan, Iran. (in Persian)
21- Sood S. and Nagar P. K. 2008. Post-harvest alterations in polyamines and ethylene in two diverse rose species. Acta Physiologia Plantarum. 30 (2): 243-248.
22- Zamani M. M. 2011. Influence of exogenous application of proline and glycine betaine on drought tolerance in grapevine. M. Sc. Thesis, University of Zanjan, Zanjan, Iran. 86pp. (in Persian with English abstract)
23- Zheng Y. and Zhang Q. 2004. Effect of polyamines and salicylic acid on postharvest storage of ‘ponkan’ mandarin. Acta Horticulture. 632: 317-320.
24- Ziosi V., Bregoli A.M., Fregola F., Costa G. and Torrigiani P. 2009. Jasmonate- induced ripening delay is associated with up-regulation of polyamine levels in peach fruit. Plant Physiology. 166: 938-946.
CAPTCHA Image