Livestock Research for Rural Development 31 (12) 2019 LRRD Misssion Guide for preparation of papers LRRD Newsletter

Citation of this paper

Restoration of the Steppe ecosystem through agroforestry: A study of the germination and emergence of Pistacia Atlantica Desf  in the El Bayadh region, Algeria

Mekhloufi Moulay Brahim, Benabdeli Khéloufi1, Tayeb Nouri2 and Mahari Latifa3

University Mustapha Stambouli, Mascara, Institute of Agronomy, Algeria
Agro752002@msn.com
1 Laboratory of Geo- Environment and Development of Spaces. University Mustapha Stambouli, Mascara, Algeria
2 Laboratory of Biodiversity and Conservation of Soils and Waters, University Center Salhi Ahmed Naâma, Algeria
3 Faculty of Sciences, Biology Department, Nouri Bachir El-Bayadh University Center, Algeria

Abstract

The steppe ecosystem can be preserved by introducing Pistacia atlantica Desf., a woody tree species with a socio-economic impact. The treatment of seeds harvested in the sylvopastoral area of the Brezina region (El Bayadh-Algeria) has improved the germination rate and has yielded interesting results. In this study, various physical pre-treatments were carried out such as scarification at different temperatures and chemical treatment with sulphuric acid, ethanol, hydrogen peroxide and gibberellin GA3. The results obtained show that the various pre-treatments tested make it possible to accelerate the germination rate. The highest germination rate (100%) was recorded in seeds that underwent cold stratification at -4°C for 10 hours, combined with mechanical scarifying and treatment of the seeds with GA3 at 100 ppm for 30 minutes. Mechanical scarification resulted in high germination rates: 88.88, 74.99%, 84.72%, 90.27%, 80.55%, 70.83%, 80.55%, 100% for the stripped seed, ethanol C2H5OH (50 pmm), C2H5OH (100 pmm), hydrogen peroxide H2O2 (50pmm), H2O 2 (100ppm), sulphuric acid H2SO4b (100ppm), gibberellic acid GA3 (50ppm) and acid GA3 (100ppm), respectively. However, stratification of seeds at -4°C with different treatments shows average germination rates of 83.85%.

Keywords: sustainable development, scarification, GA3 gibberellic acid


Introduction

The sustainable development of the steppe area requires restoration by introducing Pistacia atlantica, which is a fairly resistant species and is influenced by local ecological conditions. This tree-like woody plant is present in the Brezina region. But no longer regenerates due to various pressures (overgrazing, climate).

The multiplication of this plant in the region will have socio-economic and ecological impacts due to its agro-sylvo-pastoral importance. Several authors underline the importance of this species since all parts of the plant are used in local phytotherapy (Benaradj A et al 2015). The bark produces a mastic resin that naturally exudes abundantly in hot weather (Monjauze A 1980).

The tree provides wood for crafts and fire, and it can be used to make charcoal. Furthermore, it is a heavy and well-preserved wood (Ozenda P 1983).

The multiple forms of planting carried out in this area have resulted in failures induced by the use of non-adapted species. In this context, particular attention should be paid to local species with economic and ecological potential as they adapt to soil and climate conditions in arid and semi-arid areas. However, the use of such species requires a better understanding of their biology and mechanisms of regeneration and growth.

Some botanical and ecological factors

The genus Pistacia of the Anacardiaceae family includes many species widely distributed in the Mediterranean region and Middle East (Tutin et al 1968). The Atlas pistachio tree (Pistacia atlantica Desf.), commonly known as El Betoum, Botma in Arabic, is a woody and spontaneous species that can reach 10 m in height. The tree has an individualized trunk with hemispherical foliage (Quézel and Santa 1963).

Its compound leaves consist of seven to nine leaflets; the flowers are in loose clusters, and the fruits, which are about the size of a pea, are drupes (Ozenda 1983) that are referred to as khodiri. These fruits are consumed by the local inhabitants (Belhadj et al 2008). Fruiting begins towards the end of March, and the fruits ripen in September (Yaaqobi et al 2009).

According to Zohary (1952,1987) and Quézel and Médail (2003), this species is common in the Mediterranean and Irano-Turanian regions. However, Manjauze (1980) and Ozenda (1983) describe it as endemic to North Africa (Belhadj et al 2008). It is tolerant to several soil types, including alkalis. It can thrive with rainfall of about 150 mm and sometimes less (Benhssaini and Belkhodja 2004). Pistacia atlantica Desf. regenerates and develops in the driest places where few tree species can survive. Its growth is very slow. In Algeria, it is found in places with Ziziphus lotus, which protects young shoots from animals and strong winds (Belhadj et al 2008). It covers a large area including Morocco, Algeria, Tunisia, Libya, Syria, Jordan, Palestine, Iran and Afghanistan (Kaska et al 1996; Khaldi and Khouja 1996; Sheibani 1996). Pistacia atlantica seems to be the ideal choice for steppe enhancement work.


Materials and methods

The seeds used in the experiment were harvested at maturity in September from a seed-carrying stand located in the Brezina region (i.e., Guerar: 01°28'24.26E'' 33°11'47.55N''). The average altitude is 97 m and the rainfall regime is of the AHPE type with a 300 mm rainfall range. After harvesting, the seeds were air-dried and carefully sorted to eliminate those infected and damaged by insects. They were placed in paper bags and stored under ambient conditions and protected from light until they were used. Before use, the seeds were soaked in water for 24 hours to remove the pericarp; empty seeds were also removed.


Results

Pre-treatments

Natural exposure to cold can end seed dormancy. Furthermore, seed dormancy can also be ended by physical treatments such as stratification and scarification or the use of growth regulating hormones. Stratification is a technique used mainly to end primary morphological, physiological and morphophysiological dormancy (Geneve 2003). Stratification is effective in ending secondary dormancy. The stratification process consists of incubating the seeds in humid conditions and at low temperatures (0-10°C). The optimal temperature is 4°C for many species (Baskin and Baskin 1998). The effectiveness of stratification varies by species (Andersson and Milberg 1998; Vincent and Roberts 1977).

Seeding was carried out in cells; three repetitions of 24 seeds were carried out for each germination test. The germinated seeds were counted daily and the cumulative percentages of germination were also determined daily. A seed was considered to have germinated when the radicle became visible (Come D 1968). Mechanical scarification was done by making a small cut in the integument with green paper while respecting the integrity of the kernel. For the chemical treatment, the seeds have been soaked in the different solutions. 100 ppm and 50 ppm for 30 minutes. The seeds of Pistacia atlantica were divided into two blocks, A and B. Each batch suffered mechanical and thermal shock. The treatment method for block A consisted of immersing the seeds in boiling water for one minute and then putting them in a tank at -4°C for 12 hours. Block B underwent the opposite treatment (i.e. the seeds were placed in a cold tank at -4°C for 12 hours and immersed in a boiling water tank for one minute). Both Device A and Device B underwent the same physicochemical and hormonal treatments.

Influence of processing differences

The two pre-treated seed lots were germinated in cells for two months after sowing. The mechanically scarified seeds germinated from day 17, and the germination rate improved for bare seeds and became higher until day 47 after sowing. The mechanical scarifying clearly improved germination, as the rate increased by 88.88%. The treatment of seeds with gibberellic acid significantly increased the germination rate.

The seeds soaked for 30 min had an optimum germination interval between 12 and 20 days after sowing. However, the high germination rates were obtained after treatment with 100 ppm sulphuric acid after 12 days of sowing.

The comparison of germination rates obtained after mechanical and chemical scarifications of the seeds showed that the germination rate of seeds soaked in gibberellic acid for 30 min was significantly higher than that obtained after mechanical scarifying.

Seeds germinated and treated with gibberellic acid (GA3 at 100 ppm) had the best germination rate (100%); this rate was more than 10% higher than any other treatment.

The influence of the treatments on germination kinetics is presented in Fig. 1 where the curves represent the cumulative germination rates for a 60-day period. The species' sensitivity to different types of treatment where germination kinetics displays three phases: latency, exponential acceleration of germination after reaching maximum germination capacity. The germination rate varied according to the type of treatment; there were two doses (50ppm, 100ppm) with emergence rates of 88.88, 74.99%, 84.72%, 90.27%, 80.55%, 70.83%, 80.55%, 100% for stripped seeds, C2H5OH (50 pmm), C2H5OH (100 pmm), H 2O2 (50 pmm), H2O (100 ppm), H2 SO4 (100 ppm), GA3 (50 ppm) and GA3 (100 ppm), respectively.

Figure 1. Germination kinetics of Pistacia atlantica seeds under the effect of the different treatments
germinating at room temperature (25–30°C). N: number of germinated seeds

The results were analyzed with Stat Box software (version 6.4), and an analysis of variance was conducted at the 5% probability level. The averages are compared with the Tukey test to determine homogeneous groups at α=0.05.

Only seeds that underwent cold pre-treatment germinated. Therefore, calculations were only performed on the results of germinations of cold pre-treated seeds (Block B).

Table 1 presents the results of the variance analyses with one factor. They show that the variability of germination is highly significant. Interactions between factors are significant only for germination rate calculations, and the interaction between the control and treated grain factors is the most significant. Natural seeds had a lower germination rate and a slower median response than treated seeds. Table 2. shows that the germination rate of seeds varies according to the different treatments. GA 3 was used to end embryonic dormancy; the seeds that were treated have the highest germination rate but a relatively longer average time. Our results agree with those obtained by Ayfer and Serr (1961) and Crane and Forde (1974).

Table 1. Results of the 1-factor analysis of variance analysis comparing natural and pre-treated seeds. Level of significance: = p<0.01, p<0.05

Average

value t

dl

p

Ec-Type

Ratio F

p

 

Natural vs. Denuded

88.8867

-13.0028

4

0.000202

10.48897

6.34214

0.272400

Natural vs. C2H5OH( 50 ppm)

74.9967

-10.4129

4

0.000480

11.02144

7.00240

0.249925

Natural vs. C2H5OH( 100 ppm)

84.7200

-14.5049

4

0.000131

8.67094

4.33413

0.374944

Natural vs. H2O2( 50 ppm)

90.2767

-10.6341

4

0.000443

13.39327

10.34053

0.176359

Natural vs. H2O2( 100 ppm)

80.5533

-7.6282

4

0.001586

16.83760

16.34293

0.115321

Natural vs. H2SO4( 100 ppm)

70,8300

-9.7989

4

0.000608

11.02333

7.00480

0.249850

Natural vs. GA3 ( 50 ppm)

80,5533

-20.7967

4

0.000032

4,80933

1.33333

0.857143

Natural vs. GA3( 100 ppm)

100,0000

-39.8545

4

0.000002

0.00000

0.00000

1.000000

Scarification succeeded in increasing the germination rate over a shorter period of time. The same results were obtained by Abu-Qaoud (2007). In order to classify the lifting potential, a comparison of germination rates and average germination times was carried out using the Newman-Keuls test (Table 2). It can be seen that as soon as C2H5OH was applied, the germination capacity is slightly reduced.

Fig. 2 illustrates the variations in the average germination rates according to the different pre-treatments of scarification for two months. It shows that scarification with sulfuric acid allows a faster start of germination with higher germination rates of 70.83%. Scarification is more or less inferior to the other pre-treatments tested, namely mechanical scarification or gibberellic acid. The best average germination time, 15 days, is noted for pre-treatment with C2H5OH (100 ppm) (Table 2). These results are confirmed by the analysis of variance, which revealed a highly significant pre-treatment effect on germination rates and average germination times. They also show that there is a significant effect of the treatments on the germination rate (p < 0.05).

Table 2. Comparison of the germination rates and average germination time of Pistacia atlantica for each of the treatments

Treatments

Germination
rate (%)

Statistical
similarity of
germination means

Statistical similarity of
germination mean
(nature / intact)

Statistical similarity
of germination time
averages

C2H5OH( 50ppm)

75

A

B

17

C2H5OH( 100ppm)

84.72

A

15

H2O2( 50ppm)

90.28

A

B

18.66

H2O2( 100ppm)

80.55

A

19

H2SO4( 100ppm)

88.89

A

B

19.33

GA3 ( 50ppm)

80.55

B

C

31.33

GA3( 100ppm)

100

A

19



Figure 2. Average germination rate (%) of Pistacia atlantica under the effect of the different treatments


Discussion

The results obtained for the germination behavior of Pistacia atlantica seeds showed that the germination rate of seeds treated with GA3 reached 100%; this was the highest rate. These low germination rates are believed to be due to the presence of pericarp in fruits, which, on the one hand, prevents the integrity of the seeds from being assessed and, on the other hand, constitutes, in addition to the seed teguments, an additional barrier that limits the access of water and oxygen to the embryo. If this hypothesis is correct, the seeds would thus have an integumentary inhibition linked to the seed integuments, which would be impermeable to air and water.

However, it should be noted that this impermeability of the seed coat would also be an advantage because it would protect it from rapid germination under conditions unfavorable to the development of the plants (Grouzis M 1987; Nongonierma A 1978; penning de vries FW T 1982; Tybirk K 1991).

Mechanical scarification and GA3 seed treatment significantly increased the germination rate and speed of the Pistacia atlantica seeds compared to intact seeds (controls). The main obstacle to seed germination seems to therefore be of integumentary origin. Indeed, all pre-treatments applied to the seeds weakened the integuments and facilitated, on the one hand, the access of water and air to the embryo and, on the other hand, the root exit

The best germination rate, which was obtained after 30 minutes of immersion of the seeds in GA3, was higher than that obtained after mechanical scarification. This may be partly explained by the effect of GA 3 on abscisic acid (ABA), which is the primary inhibitor of germination in many seeds (Pinfield and Gwarazimba 1992). Embryonic dormancy is directly related to ABA production (Hilhorst and Karsseen 1992).

The synthesis of ABA is accelerated in response to stress factors such as water stressors (Yoshioka et al 1995). Lack of oxygen increases the amount of endogenous ABA and decreases the amount of GA3 and cytokinin in maize seeds (Prasad et al 1983), thus facilitating the absorption of water and oxygen that are essential for germination. However, since mechanical scarification is only sectarian, it does not facilitate the imbibition and expansion of the embryo as much. Optimal germination temperatures vary from one species to another. For Pistacia atlantica, the optimal germination temperature is between 25 and 30°C, which was confirmed by our experience. Although the germination rate is slightly higher at 25°C, the germination rate is higher at 30°C. These results are relatively consistent with those of Grouzis et al (1986), who found the optimal seed temperature of Pistacia atlantica to be 30°C.


Conclusion


Acknowledgments

I would like to express my thanks to the staff of the laboratory of Faculty of Sciences, Biology Department of the Nour Bachir El-Bayadh University Center (Algeria) for its help in carrying out this study.


References

Abu-Qaoud H 2007 Effect of scarification, gibberellic acid and stratification on seed germination of Three Pistacia Species. An - Najah Univ. J. Res.(N. Sc.),21:1-11. https://repository.najah.edu/handle/20.500.11888/1858

Andersson Land Milberg P 1998 Variation in seed dormancy among mother plants, populations and years of seed collection. Seed Science Research, 8(1), 29-38. doi:10.1017/S0960258500003883

Ayfer M and Serr E F 1961 Effects of gibberellin and other factors and seed germination and early growth in Pistacia species. Proc. Amer. Soc. Hott. Sci., 77: 308-31 5.

Benaradj A, Boucherit H, Bouazza M et Hasnaoui O 2015 Ethnobotanique du pistachier de l’atlas (Pistacia atlantica) auprès la population de Béchar (Algérie occidentale), Journal of Advanced Research in Science and Technology, 2 (1): 139-146. https://pdfs.semanticscholar.org/9fc4/8b4d5683bc8b8e46d34e4d6544ae19d6cadf.pdf

Baskin C C, Baskin J M 1998 Seeds: ecology, biogeography, and evolution of dormancy and germination. Academic Press, San Diego. 666 p. https://doi.org/10.1111/j.1756-1051.2000.tb01610.x

Belhadj S, Derridj A, Auda Y, Gers C, Gauquelin, T 2008 Analyse de la variabilité morphologique chez huit populations spontanées de Pistacia atlantica en Algérie. Botany, 86 : 520-532. https://www.researchgate.net/publication/237153058

Benhssaini H, and Belkhodja M 2004 Le pistachier de l’Atlas en Algérie entre la survie et disparition. La feuille et l’aiguille, 54 : 1-.http://www.sciencedirect.com/science/article/pii/S1876610215013612

Come D 1968 Problèmes de terminologie poses par la germination et ses obstacles. Bull. Soc. Fr. Physiol. veg., 14 : 3-9.). http://www.univ-bejaia.dz/dspace/bitstream/handle/123456789/11974

Crane J C and Forde H I 1974 Improved Pistacia seed germination. California Agriculture, 28(9): 8-9.

Geneve R L 2003 Impact of temperature on seed dormancy. Hort Science, 38: 336341. https://pdfs.semanticscholar.org/3c83/6725e0c134854c99ffc9a331778b761c90bb.pdf

Grouzis M, Legrand E and Pale F 1986 Germination des semences des régions semi-arides du Sahel. In : Actes du colloque Les végétaux en milieu aride, 8-10 septembre1986, Djerba, Tunisie, 534-552.

Grouzis M 1987 Structure, productivite et dynamique des systemes ecologiques sahéliens (mare d’Oursi, Burkina Faso). These Doct. Sciences nat., universite de Paris-Orsay, France, 336 p. http://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_2/etudes_theses/25739.pdf

Hilhorst H W M, and Karssen C M 1992 Seed dormancy and germination: the role of abscisic acid and gibberellins and the importance of hormone mutants. PlantGrowth Regulation, 11 : 225-238.https://doi.org/10.1007/BF00024561

Kaska N, Caglar S and Kafkas S 1996 Genetic diversity and germplasm conservation of Pistacia species in Turkey. In: Workshop “Taxonomy,distribution, conservation and uses of Pistacia genetic resources”, Padulosi S.,Caruso T. and Barone E., Palermo, Italy, 1995. IPGRI, Rome, Italy, pp: 46-50.

Khaldi A, and Khouja M K 1996 Atlas pistachio (Pistacia atlantica Desf.). North Africa taxonomy, geographical distribution, utilisation and conservation. In:Workshop “Taxonomy, distribution, conservation and uses of Pistacia geneticresources”, Padulosi S., Caruso T. and Barone S. Palermo, Italy, 1995. IPGRI,Rome, Italy, pp: 57-62.

Monjauze A 1980 Connaissance du bétoum Pistacia atlantica Desf. Biol for, 4 (32): 356–363. DOI: 10.4267/2042/21418

Nongonierma A 1978 Contribution a l’etude biosystematique du genre Acacia Miller en Afrique occidentale. These Doct., faculte desSciences et techniques, universite de Dakar, Senegal, 451 p. (tome I), tableaux (tome II). https://scholar.google.com/citations?user=K9k-6ZYAAAAJethl=en

Ozenda P 1983 Flore du Sahara. 2ème Ed. Centre national de la recherche scientifique, Paris, 622 p.

Penning de Vries F W T and Djiteye M A 1982 La productivitedes paturages saheliens, une etude des sols des vegetations et del’exploitation de cette ressource naturelle. Wageningen, TheNetherlands, Cabo, Pudoc, 525 p.

Pinfield N J and Gwarazimba V E E 1992 Seed dormancy in Acer: The role of abscisic acid in the regulation of seed development in Acer platanoides L. plantgrowth regulation, 11: 293-299.https://doi.org/10.1007/BF00024568

Prasad V N, Gupta V N P and Bajracharya D 1983 Alleviation of gibberellic acid and kinetin of the inhibition of seed sermination in maize (Zea mays L.) under submerged conditions. Annals of Botany, 52: 649-652. https://doi.org/10.1093/oxfordjournals.aob.a086620

Quézel P and Médail F 2003 Ecologie et biogéographie des forêts du bassin méditerranéen. Collection Environnement. Elsevier, Paris, France.http://dx.doi.org/10.4236/oje.2013.35042

Quézel P and Santa S 1963 Nouvelle flore de l’Algérie et des régions désertiques méridionales. Tome 2. Centre national de la recherche scientifique, Paris,France. DOI: 10.4236/oje.2014.49046

Sheibani A 1996 Distribution, use and conservation of pistachio in Iran. In:Workshop “Taxonomy, distribution, conservation and uses of Pistacia genetic resources”, Padulosi S., Caruso T. and Barone E., Palermo, Italy, 1995. IPGRI,Rome, Italy, pp: 51- 56.

Tutin T G, Heywood V H and Burgess N A 1968 Flora Europaea. CambridgeUniversity Press, Cambridge, UK, vol 2, p. 237.

Tybirk K 1991 Regeneration des legumineuses ligneuses auSahel. Aarhus, Danemark, Botanical Institute, Aarhus University, 86 p.(Report n° 28)

Vincent E M and Roberts E H 1977 The interaction of light, nitrate and alternating temperature in promoting the germination of dormant seeds of common weed species. Seed Science and Technology, 5: 659-670. http://agris.fao.org/agris-search/search.do?recordID=NL19780288959

Yaaqobi A, El Hafid L and Haloui B 2009 Etude biologique de Pistacia atlantica Desf. de la région orientale du Maroc, Biomatec Echo, 3 : 39-49. https://www.doc-developpement-durable.org/file/Huiles-vegetales-noix/Fiches_plantes/pistachier%20-%20pistache/article-PISTACIA%20ATLANTICA-Maroc.pdf

Yoshioka T, Ota H Segawa K Takeda Y and Esashi Y 1995 Contrasted effects of C02 on the regulation of dormancy and germination in Xanthium pennsylvanicum and Setaria faberi seeds. Annals of Botany, 76: 625-630. https://doi.org/10.1006/anbo.1995.1140

Zohary M 1952 A monographical study of the genus Pistacia. J. series. Vol.5.Palestine Journ Bot, 4 : 187–228.DOI: 10.4236/ajps.2014.520306

Zohary M 1987 Flora Palaestina. Platanaceae to Umbelliferae. Second printing.Israel Academy of Sciences and Humanities, 2: 296–30.


Received 4 November 2019; Accepted 4 November 2019; Published 2 December 2019

Go to top