Karnataka J. Agric. Sci.,25 (4) : (455-459) 2012

A phenological study of Casuarina species RAJU CHAVAN¹, S. VISWANATH², SHIVANNA, H.³ AND B .V. TEMBHURNE1 1

College of Agriculture, University of Agricultural Sciences, Raichur - 584 102, India 2 Division of TIP, IWST, Malleshwaram, Bangalore, India 3 College of Forestry, Sirsi-581401, India Email: [email protected] (Received: July, 2011

;

Accepted: September, 2012)

Abstract : Synchronization of male and female flowering behavior was recorded between C. equisetifolia and C. cunninghamiana. Among the five species of Casuarina, C. equisetifolia have monoecious as well as dioecious while others C. obesa, C. glauca and C. cristata were strictly dioecious with female genders. However, C. cunninghamiana was separate genders. Phenotypic variability of male and female floral traits was significantly higher in dioecy than the monoecy in Casuarina equisetifolia. It was observed that hand pollination registered lower seed set than the open pollination in all these species and were able to flower twice in a year (fourth week of January to end of May and third week of July to end of October). Fruit maturity duration was short (18 weeks) in both C. equisetifolia and C. cunninghamiana than other three species of Casuarina (20 weeks). Fruit reproductive biology revealed that open pollination was the dominant reproductive system over controlled pollination in natural populations. Key words: Casuarina, Floral traits, Fruit maturity, Phenology

Introduction Casuarina (derived from the Latin word Casuarius meaning Cassowary) belonging to the Family Casuarinaceae, comprises about 50 species and native of Australia (Subbarao and Rodriguez, 1993) with chromosome number n=9 (Turnbull, 1990). Casuarinas are very distinctive group of plants and superficially resemble coniferous with their wire like foliage and woody fruiting structures, with thin crowns of drooping branches and leaves reduced to scales (Johnson and Wilson, 1989). It was first introduced to India at Karwar coastal region in 1668 (Ataia, 1983). Farmers cultivating it extensively in West coasts and Northern dry zone of Karnataka, East coasts of Tamil Nadu, Andhra Pradesh and Orissa. The species is endowed with high degree of climatic adaptability. It thrives well in areas having an annual rainfall ranging from 250 to 2,500 mm, maximum temperature as high as 48°C and tolerates cold up to 0°C, on altitudes up to 1,200 m. It is a light demanding tree and grows in almost all types of soil and is highly tolerant to soil salinity (Anon, 1985). Their distributions become widened after introduction to the Indian sub-continent in the sixties of the last century for supply of firewood to steam locomotive with multiple uses (Kondas, 1983). Casuarina species were successfully introduced in Northern dry zone of Karnataka, to identify the best performing species against soil salinity. Knowledge on reproduction is a prerequisite to delineate the numeric, gender and genetic composition to initiate the breeding programs. Synchronization of the species is prerequisite for the hybridization and/or population improvement programmes. But published information on synchronization of male and female inflorescence and phenology is not available for five species available in this region. Hence, this study was aimed to investigate the phenotypic variability in floral traits and reproductive success of five Casuarina species. Material and methods

(16° 15' N and 77° 21' E) at an altitude of 389 meters above the mean sea level, with an average rainfall of 660 mm. However, climate at the experimental site is typically semi arid, characterized by exceptionally hot dry summer, sub-humid monsoon and cold dry winters. Properties of black cotton soil as follows viz., bulk density (1.38), soil pH (8.31), soil EC (1.17 dS/ml), nitrogen (134.14 kg ha-1), phosphorous (15.33 kg ha-1) and potassium (401.75 kg ha-1). Seeds of five species of Casuarina namely Casuarina equisetifolia, C. obesa, C. cunninghamiana, C. glauca and C. cristata were imported from Australia under Indian Council of Forestry Research and Education, Dehara Dun free funded project to study the best performing species in saline soil. Seedlings of Casuarina species were raised and planted in the year 1999 at a spacing of 2.5 m x 2.5 m having 4 replications in a Randomized complete block design of experimental trial under rain fed condition. 20 trees in each replication from each species were selected for morphological observations. The observation were recorded during 2008-09 when Casuarina species attended an average growth of 13.56 m height & 13.76 cm diameter at breast height for C. equisetifolia, followed by C. obesa with (11.40 m ht & 11.87 cm dbh), C. glauca (12.61 m ht & 13.09 cm dbh), C. cunninghamiana (12.43 m ht & 12.79 cm dbh) and C. cristata (11.85 m ht & 11.89 cm dbh). Phenological observations were recorded at the interval of seven days for two consecutive flowering seasons during 2008-09. The frequency and duration of flowering were observed by selecting 100 inflorescences randomly during peak flowering period from single tree at different part of the crown. A comparative studies on male expression of monoecy and dioecy of same species for reproductive success was investigated by selecting, bagging and pollinating 100 female inflorescences by hand with pollen from same tree (monoecy) and another male tree (dioecy) and compared it with open pollination based on fruit set per inflorescence. Results and discussion

The study was conducted in Agricultural Research station at Gangavati, University of Agricultural Sciences, Raichur situated in the North East Dry Zone of Karnataka between 455

All Casuarina species flowered twice in a year coinciding with the South West and North East monsoons. The first season

Karnataka J. Agric. Sci., 25 (4) : 2012 was between late January to early May and the second season from third week of July to early October (Table 1 and Fig.1). The flowers of Casuarina species were unisexual and male and female inflorescence was quite different in appearance. C. equisetifolia have monoecious as well as dioecious species while others C. obesa, C. glauca and C. cristata were strictly dioecious with female genders. However, C. cunninghamiana was with separate genders (Table 2). The findings of the present study was in conformity with that of Parrotta (1993) who

reported that Casuarina equisetifolia is monoecious as well as dioecious, Boland et al. (1996) also stated genders were separate in C. cunninghamiana and Warrier et al. (2001) who opined that sexual variation in C. equisetifolia. The morphological traits revealed from Table 3 that length of male inflorescence (6.10 cm), width (4.21 mm) and number of floral whorls per cm per inflorescence (10.08) were significantly higher in dioecy of C. equisetifolia than the monoecy. However, dioecy of C. cunninghamiana was shown

Table 1. Phenology of five Casuarina species in northern dry zone of Karnataka Casuarina species C.equisetifolia I Season II Season C. obesa I Season II Season C.glauca I Season II season C.cunninghamiana I Season II Season C.cristata I Season II Season

Male flower blooming duration Initiate End 4th week January 3nd week July -

1st week May 4th week October -

-

August -

4th week January 3nd week July -

August 1st week May 4th week October -

-

-

Female flower blooming duration Initiate End 1st week February 4th week July 2nd week February 1nd week October 2nd week February 1nd week October 1st week February 4th week July 2nd week February 1nd week August

1st week May 4thWeek October 2nd week May 4th week September 4th week May 4nd week September 1st week May 4thWeek October 4th week May 4th week October

456

Peak period of female flower blooming Initiate End

Fruit initiation

Fruit Fruit Maturity Collection

2nd week March 1st week September 3rd week March 2nd week October 2nd week March 2nd week October 2nd week March 1st week September 2nd week March 2nd week September

2nd Week February 1st week August 3rd week February 2nd week December 3rd week February 2nd week December 2nd Week February 1st week August 3rd week February 2nd week August

3rd week June June 2nd week November December 2nd week July July 2nd week December

1st week April 4thWeek September 2nd week April 1st Week August 1st Week April 1st Week August 1st week April 4thWeek September 1st Week April 1st Week October

2nd week July July 2nd week December 3rd week June June 2nd week November December 2nd week July July 2nd week December December

A phenological study of .... on par with average value. The presence of wide variation in Casuarina species have also been reported by Wilson and Johnson (2008) who stated male flowers of cunninghamiana, were smaller than C. equisetifolia, Pinyopusarek et al. (2004) in C. equisetifolia, Boland et al. (1996) in C. cunninghamiana and Barrett (1956) in Casuarina species, reported wide variation. Male inflorescences occur on simple, terminal, elongated spikes and flowering period was noticed from late January to early May with peak flowering from second week of March to first week of April for C. equisetifolia and C. cunninghamiana. Further peak flowering was recorded in second week of March to first week of April in both species during first season. However, male flowering period was observed from third week of July to fourth week of October in C. equisetifolia and C. cunninghamiana. Similarly peak flowering was found in September during second season (Fig.1). The findings are similar to that of Troup (1921) opined that two flowering seasons in April and October and two fruiting seasons in June and December in Casuarina species. Most of the flowers open during early morning after 1.00 AM and pollen was ready to dehisce by 7.00 am. Pollen was steadily released in to air with increase of day temperature (22 ºC–28 ºC) (Table 3). Flowers color were light brown, male inflorescences in monoecious individuals were shorter than dioecious. However, male flower crowded in rings of narrow pointed scales consist of one stamen less than 4.0 mm long with two tiny sepal scales at base. Male trees flowered two weeks ahead of female trees. The interval between two successive flowerings was longer in female (2-3 weeks) than males (6-8 days) (Table 1). The present study was also in agreement with that of Nagarajan et al., (2006) who registered twice flowering in Casuarina equisetifolia within a year. Phenotypic variability for six morphological female floral parameters viz., inflorescence length (9.79 mm), flower width

(5.01 mm), stigma length (2.57 mm), stigma width (2.96 mm.) and number of floral buds per inflorescence (54.00) were recorded significantly higher in dioecy than the monoecy of C. equisetifolia and other four species. However, all traits were showed significantly lower in C. obesa, C. glauca and C. cristata. While, female floral traits of C. cunninghamiana has found on par with C. equisetifolia (Table 4). Several workers have been reported variation in female morphological traits viz., Pinyopusarek et al. (2004) and Whistler and Elevitch (2006) observed unisexual 1.0 cm long inflorescence in C. equisetifolia. The instant synchronization for male and female flowering was exhibited between first week of February to early May in C. equisetifolia and C. cunninghamiana (Fig. 1). Similar flowering was noticed between second week of February to second week of May with peak flowering period between third week of March to second week of April during first season in C. obesa, C. glauca and C. cristata. However, second season of flowering was observed between fourth week of July to fourth week of October in C. equisetifolia and C. cunninghamiana with peak period of flowering in September. While, C. obesa, C. glauca and C. cristata were flowering recorded between first week of August to late October with peak period of flowering between second week of September to early October during second season. The findings of the present study was similar to those of Elbert and Roger, (2003) who reported twice flowering in a year for Casuarina species and Nicodemus et al. (2001) also opined that flowering occurs throughout the year in Casuarina species. The fruit initiation was observed between second week of February (after 2 weeks of late flowering) and maturity of fruit was between second week of June to July for C. equisetifolia, followed by C. cunninghamiana (Fig.1). Similarly fruit initiation was recorded between third week of February and maturity of fruit between fourth week of June to late July during first season for C. obesa followed by C. glauca and C. cristata. However,

Table 2. Different Casuarina species with monoecy and dioecy nature Casuarina species Casuarina equisetifolia Casuarina obesa Casuarina glauca Casuarina cunningahamiana Casuarina cristata

Number of trees with both anthers & stigma

Number of trees with anthers

Number of trees with stigma

Total number of trees

25 0 0 0 0

10 0 0 15 0

45 80 80 65 80

80 80 80 80 80

Table 3. Phenotypic variability for male inflorescence in Casuarina species Casuarina species

C.equisetifolia (Dioecy) C.equisetifolia (Monoecy) C.cunninghamiana Mean S.Em ± C.D. (0.05) C.V. (%)

Length of flower (cm)

Width of flower (mm)

No. of floral. Length of . whorls per cm stamen (mm)

Width of stamen (mm)

Late night

Pollen dehisce

Day temperature pollen steadily released to air

6.10

4.21

10.08

3.21

2.10

1.00 am

6 .30- 7.30am

22 - 32º C

4.13

3.70

8.89

2.91

2.00

1.00 am

6 .30- 7.30am

22 – 32ºC

4.39 4.87 0.35 1.07 22.19

3.95 3.95 0.09 0.28 4.78

9.18 9.35 0.13 0.40 2.92

2.75 2.96 0.06 0.17 4.11

2.00 2.03

1.00 am

6.00 - 7.30am

22 - 32º C

457

NS

Karnataka J. Agric. Sci., 25 (4) : 2012 Table 4. Morphological traits of female inflorescence in Casuarina species Casuarina species

C. equisetifolia (dioecy) C. equisetifolia (monoecy) C. obesa C. gluaca C. cunningahamiana C. cristata Mean S.Em ± C.D. (0.05) C.V. (%)

Length of flower (mm)

Width of flower (mm)

Length of stigma (mm)

Width of stigma mm

No. ovules per ovary

No. of floral buds per inflorescence

Shape of flower

9.79 7.90 7.69 8.65 9.55 7.78 8.56 0.08 0.24 1.81

5.01 4.80 4.30 4.15 4.75 3.99 4.50 0.14 0.42 6.19

2.57 2.20 1.83 1.84 2.23 2.04 2.13 0.05 0.16 4.93

2.96 2.74 2.39 2.36 2.75 2.51 2.62 0.04 0.13 3.21

5 4 4 4 5 5 4.50

54.00 53.50 23.10 22.84 31.76 23.52 34.79 0.66 2.05 4.28

Disk Disk Disk Disk Disk Disk

initiation of fruiting was registered between first week of August and maturity between second week of December in C. equisetifolia and C. cunninghamiana. But C. obesa, C. glauca and C. cristata were initiated fruit set in second week of August and fruit maturity was recorded in early December during second season. Fruit maturity duration was higher in C. obesa followed by C. glauca and C.cristata with 20 weeks and lower was in C. equisetifolia and C. cunninghamiana with 18 week for each of species. Collection of fruits was recorded between June in first season and December in second season of flowering (Fig 1). The present study was supported by Olson et al. (1993) in Casuarina species, Parrotta (1993) in Casuarinas and Whistler and Elevitch (2006) also opined that flowering and fruiting occur throughout the year and peak flowering was usually from April to June with fruit opening from September to December and mature in 18 to 20 week after anthesis in Casuarina species. The results of Table 5 revealed that the female reproductive success in open pollination was significantly higher (87.24 %) in dioecy of Casuarina equisetifolia than the hand pollination (71.43 %) as well as control self pollination in monoecy (67.80 %). This behavior varies from one species to another species of Casuarina. However, C. equisetifolia with dioecious nature recorded significantly higher seed packing or filling per cone

(92.42 %), number of fruit set per inflorescence (35.74), percent fruit set per inflorescence (71.34 %) and short maturity duration of fruit (18 weeks) as compared to others species like C. obesa, C. glauca and C. cristata. Similar trend has been recorded in monoecy of C. equisetifolia and dioecy of C. cunninghamiana. While open pollination registered highest number of fruit set when compared to hand pollination in monoecy of C. equisetifolia. The present study was in agreement with that of Nagarajan et al. (2001) and Nicodemus et al. (2001). Present study revealed that all the five species studied were able to bloom twice in a year (first week of January to first week of May and third week of July to fourth week of October). Male and female inflorescences of dioecious species of C. equisetifolia were significantly higher than that of monoecious C. equisetifolia and other species of Casuarinas. Interestingly synchronization of flowering for male and female inflorescence was recorded in both species of C. equisetifolia and C. cunninghamiana along with lesser duration (18 week) of fruit maturity. Hence, these two species may be recommended for hybridization and tree improvement programme at Northern dry zone of Karnataka after confirming their cross compatibility between these two species. All the five Casuarina species studied were recorded higher rate of fruit setting in open pollination than controlled

Table 5. Female reproductive success in different Casuarina species Casuarina Number of Open Fruit set Cross Fruit set in species ovaries pollinain open pollinapollination pollination tion tion C. equisetifolia (dioecy) C.equisetifolia (monoecy) C. obese C. gluaca C. cunninga-hamiana C. cristata Mean S.Em ± C.D. ( 0.05) C.V. (%)

NS

Self Fruit set in Number Number of Percent of Cone / pollinaself of seeds fruit set fruit fruit tion pollina- per cone per set per maturity tion (% ) infloreinflorein -scence -scence weeks 92.42 34.14 71.34 18

50

43.64

87.24

33.55

71.43

50

43.37

86.75

-

-

33.93

67.80

90.05

34.35

70.05

20

50 50 50

40.52 41.28 42.33

81.28 83.38 85.23

27.84 31.25 32.38

55.80 62.24 64.72

-

-

84.38 76.67 71.29

20.76 13.64 26.37

53.98 61.15 66.05

20 20 18

50

40.38 41.63 0.31 0.95 1.48

80.43 83.51 0.43 1.31 1.02

31.05 31.21 0.22 0.67 1.40

61.52 63.14 0.39 1.19 1.24

-

-

75.33 81.86 2.38 7.32 5.49

22.94 25.60 0.48 1.48 4.06

63.08 64.21 0.52 1.59 1.65

20 19.2

458

NS

A phenological study of .... pollination done by bagging of inflorescence, in monoecy and hand pollination in dioecy reveals that open pollination is the predominant system over control hand pollination.

Hence, these species can be utilized for creation of variability for their genetic improvement and large scale seed production by open pollination.

References

Nicodemus, A., Varghese, M. and Nagarajan, B., 2001, Genetic Improvement of Casuarina equisetifolia through selection and Breeding, In. Casuarina: Improvement and Utilization. In: Gurumurthi, K. Nicodemus, A. and Siddappa (eds.). Institute of forest Genetics and Tree breeding Coimbatore, pp 3-8.

Anonymous, 1985, Casuarina equisetifolia grows well in heavy textured coastal Saline Soils. Indian Farming, 36 (5): 17-19. Ataia, A., 1983, Casuarina equisetifolia in the Eastern highlands province of Papua New Guinea. In: S.J. Midgley, J.W. Turnbull and R.D. Johnston, (eds.). Casuarina Ecology Management and Utilization, CSIRO, Melbourne, pp. 80–88 Barrett, M. F., 1956, Common exotic trees of south Florida. University of Florida Press, Gainesville, Florida, 26: 58-62. Boland, D. J., Moncur, M. W. and Pinyopusarerk, K., 1996, Review of some floral and vegetative aspects to consider when domesticating Casuarina. In: Pinyopusarerk, K., J. W. Turnbull and S. J. Midgley (eds.). Recent Casuarina Research and Development, Proc. of the third International Casuarina workshop Da Nang, Vietnam 4–7, March, 1996, pp. 17–25. Elbert, L., Little, Jr. and Skolmen, R. G., 2003, “Long leaf Casuarinas” published by the College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, pp.124-129. Johanson, L.A.S. and Wilson, K.L., 1989, Casuarinaceae: synopsis. In. Evolution systematic and fossil history of the Hamelidae. Higher Hamamelidae, Systemic Association, Special volume No 40 B. Calarendon press Oxford, 2:17-188. Kondas, S., 1983, Casuarina equisetifolia a multipurpose cash crop in India. In Casuarina Ecology Management and Utilization. In: S.J. Midgley, J.W. Turn bull and Johnson (eds.). CISRO. Melbourne, pp. 66–76. Nagarajan, B. A., Nicodemus, Varghese, M. and Sivakumar, V., 2001, Reproductive Biology of Casuarina equisetifolia. In: Casuarina: Improvement and Utilisation In: K. Gurumurthy, A. Nicodemus and Sidappa (eds.). Institute of Forest Genetics and Tree Breeding, Coimbatore, pp. 63–68. Nagarajan, B., Nicodemus, A., Sivakumar, V., Mandal, A. K., Kumarvelu, G. and Jayaraj, C., 2006, Phenology and Control Pollination Studies in Casuarina equisetifolia Forst. Silvae Genetica. 55 (4–5): 149-155.

Olson, D. F., Jr., Petteys, E. Q. P. and Parrotta, A. J., 1993, “Casuarina” In: Schopmeyer CS, tech. coord. Seeds of woody plants in the United States. Agric. Handbook, 450: 278-280. Parrotta, J. A., 1993, Casuarina equisetifolia L. ex J. R. & G. Forst. Casuarina, Australian pine. Research notes, New Orleans: USDA Forest Service, Southern Forest Experiment Station, pp. 11-14. Pinyopusarek, K., Kalinganire, A., Williams, E. R. and Aken, K.M., 2004, “Evaluation of International Provenance trial of Casuarina equisetifolia”. ACIAR Technical report-58, Australian Centre for International Agricultural Research, Canberra. Subbarao, N. S. and Rodriguez Barrueco, C., 1993, Symbiosis in Nitrogen fixing trees. Oxford and IBH., Pub. Co., New Delhi. Troup, R. S., 1921, The Silviculture of Indian Trees. Vol.III. Clarendon press, Oxford Turnbull, J. W., 1990, Taxonomy and Genetic variation in Casuarinas. Advances in Casuarina Research and Utilization. In: El-Lakany, M. H., Turnbull, J. W. and Brewbaker, J. L., (eds.). Proceedings of workshop, 1990 January, 15-20, Desert Development Center, American University in Cairo. pp.1-11. Warrier, Kannan, Chandra shekara, K. G., Ajith kumar, R., Rekha, Warrier and Gurumurthi, 2001, Studies on sexual variation in clones of Casuarina equisetifolia Forst. Indian J. Forest, 127(8):865-869. Whistler, W. A. and Elevitch, C. R., 2006, Casuarina equisetifolia (reach she-oak) and C. cunninghamiana (river she-oak), ver. 2.1. In: Elevitch, C.R.(ed.). Species Profiles for Pacific Island Agro forestry. http://www.traditionaltree.org. Wilson, K. L. and Johnson, L. A. S., 2008, Casuarinaceae. In: George, A. S. (ed.) Flora of Australia, vol. 3. Hamamelidales to Casuarinales, Aus. Govt. Printing Service, Canberra.

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