The International Journal of Plant Reproductive Biology
(Indexed by CABI)
ISSN Print : 0975-4296; ISSN Online : 2249-7390
 
Volume-4, Number-2, June 2012
 

Abnormal Asexual Reproduction in Asterella khasyana (Griff.) Pandé, K.P.Srivast. & Sultan Khan (Marchantiophyta: Hepaticae) from Nagaland

S.K. Chaturvedi & Kazhuhrii Eshuo
Department of Botany, Nagaland University, Lumami, Mokokchung-798601, Nagaland, India

e-mail:
sunchat1@rediffmail.com & kazhuhrii@gmail.com
Received : 9.3.2012; Revised : 3.4.2012; Published on line : 1.6.2012

  ABSTRACT

Asexual reproduction due to death and decay of the thalli is a common phenomenon among liverworts. Unusual mode of asexual reproduction due to the development of vegetative thalli from the tissues of male receptacle in Marchantia palmata has been reported earlier. The production of abnormal reproductive structures has also been reported in various species of genus Marchantia, viz., M. subintegra, M. polymorpha and M. palmata. However, formation of vegetative thalli from the tissues of carpocephalum in the genus Asterella P. Beauv. has not been reported so far. The present communication is the first report on the development of vegetative thalli from the tissues of carpocephalum in Asterella khasyana (Griff.) Pandé, K.P. Srivast. & Sultan Khan. This is an abnormal asexual reproduction among thalloid liverworts from Nagaland (North East India).

Keywords : Asterella khasyana, asexual reproduction, carpocephalum, Nagaland (North-East India).

 
 

In vitro Study on Growth and Gametangial Induction in a Liverwort Asterella wallichiana (Lehm. et Lindenb.) Grolle

Vishal Awasthi1, Virendra Nath1*, Neerja Pande2 and A.K. Asthana1
1 Bryology Laboratory, C.S.I.R. – National Botanical Research Institute, Lucknow–226001, India
2 Department of Botany, Kumaun University, Nainital–263002, India

*e-mail:
drvirendranath2001@rediffmail.com
Received : 1.5.2012; Revised : 17.6.2012; Published on line : 1.7.201

  ABSTRACT

Establishment of axenic culture and in vitro propagation of a thalloid liverwort Asterella wallichiana (Lehm. et Lindenb.) Grolle have been carried out by inoculating its spores into defined inorganic media under controlled physical conditions to determine the optimal conditions for the growth and gametangial induction in this species. Dilute nutrient medium comprising only macronutrients was found optimal for spore germination while further differentiation into mature thalli needed addition of micronutrients. Spores inoculated into half strength Knop's macronutrients + Nitsch trace elements along with 10 ppm freshly prepared ferric citrate produced well differentiated thalli, while the same when supplemented with 1% sucrose produced a cluster of many well developed and vigorous thalli within 12 weeks of culture. An enhanced growth has been observed in continuous light of 4000-5500 lux at a temperature of 21 ± 2ºC. MS medium favoured callus formationfrom the entire epidermis of thalli while Gamborg B-5 medium induced dark blackish green pulpy mass of deformed thalli. Thalli developed in culture were acclimatized and transferred to soil for their further propagation where gametangial induction occurred at low temperature and short day condition; light period (1600-2000 lux) of 10 hours at 16–18ºC and dark period of 14 hours at 15ºC.

Keywords : Acclimatization, Asterella wallichiana (Lehm. et Lindenb.) Grolle, propagation, spores

 

 
  Endogenous gemmae in certain Lejeuneaceae (Marchantiophyta)

Tamás Pócs
Department of Botany, Institute of Biology, Eszterházy Károly College, Pf. 43, H-3301, Eger, Hungary

e-mail:
colura@chello.hu
Received : 14.06.2012; Revised : 20.6.2012; Published on line : 1.7.2012

  ABSTRACT

Endogenous gemmae are known among thalloid liverworts in many species while among the leafy liverworts only in one species of Bazzania, Solenostoma and Schistochila. The long ago established and accepted view is, that gemmae inLejeuneaceae, especially the disciform gemmae in Cololejeunea, develop exogenously. Endogenously developed multicellular disciform gemmae were found in two species of the genus Cololejeunea and also in two species of the genus Colura. They originated by the multiple division inside of a projecting phylloid cell, then, reaching their final cell number arereleased through the hole of torn outer cell wall of their mother cell.

Keywords : Cololejeunea, colonization, Colura, discoid gemmae, dispersal, epiphyllous liverworts, asexual reproduction

 
  Integrity and Reliability System in Ontogenesis and Evolution

Batygina T.B.
Komarov Botanical Institute of Russian Academy of Sciences, St-Petersburg, Russia

Received : 7.5.2012; Accepted : 30.6.2012; Published on line : 1.7.2012

  ABSTRACT

Present study deals with various forms and modes of the formation of various reserves at different hierarchy levels have been studied that allows unify the notion of the system (“reserves”, “failures”, “double structures”) and determined finally the measure of integrity of system of different type. There are three main types of reproductive system, where all elements occur to be in correlative dependence: stamens – filament – anther, ovary – archesporium – sporogenous cells – ovule – fertilization – embryo – endosperm – seed – fruit, embryo (autonomy of embryo) – endosperm – seed coat – seedling. Actual issue today is to develop theoretical foundations and principles of reproductive biology and of the cardinal problem of developmental biology – problem of the integrity for the representatives of various kingdoms. This allows us to identify correlations and study correlative dependences of various reproductive structures at different levels of hierarchy.

Keywords : Integrity, Reliability System, Ontogenesis, Evolution.

 

 
 

Nectar characteristics and pollinators for three native, co-occurring insectpollinated Passiflora (Passifloraceae) from central Argentina

Carolina Torres1,2, José S. Dambolena1,3, María P. Zunino1,3 & Leonardo Galetto1,2,*
1
Instituto Multidisciplinario de Biología Vegetal (UNC-CONICET), Casilla de Correo 495, 5000 Córdoba, Argentina.
2
Cátedra de Diversidad Vegetal II, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba,
Argentina.

3Cátedra de Química Orgánica y Productos Naturales, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina.

*e-mail: leo@imbiv.unc.edu.ar
Received : 5.6.2012; Published on line : 1.7.2012

  ABSTRACT

Floral biology, nectar traits and pollinators were studied in different species of Passiflora, co-occurring in their southern area of distribution. Volume, concentration, and sugar amount of nectar per flower were measured in the native, insect-pollinated Passiflora caerulea, P. foetida and P. suberosa (Passifloraceae). Qualitative and quantitative nectar sugar composition were determined and compared between species. Pollinators were recorded and related to both floral and nectar traits. Flowers of the three species display the usual floral sexualphases described for the genus. In general, nectar traits were variable between species but relatively constant within each one. Nectar sugars were glucose, fructose and sucrose in relatively constant proportions among samples of the same species, but each species showed a particular sugar composition (P.foetida, P. caerulea and P. suberosa with lower, intermediate and higher proportion of sucrose, respectively). Bombus spp. and Xylocopa splendidula were recorded as the main pollinators for P. caerulea; Bombus opifex, Melissoptila sp., and Thygater sp. for P. foetida, and different species of wasps for P. suberosa. Bees seem to prefer larger amounts of nectar with hexose predominance, while wasps less amount of almost pure sucrose nectar. These species of Passiflora need pollinators to assure high fruit and seed sets. On the other hand, plants of these species mature many birddispersed fruits every season indicating that plant-pollinator interactions are healthy although the actual high rates of deforestation in the region.

Keywords : Nectar sugar composition, bumblebees, wasps, pollinator preferences, plant reproduction

 

 
 

Impact of temperature on Reproductive biology of Abutilon indicum (L.) Sweet (Malvaceae)

Pravendra Kumar1, *Seema Chauhan and *Anita Rana
1Academy of Life Sciences, 8/13 I Kaushalpur Bye Pass Road, Agra-282005 (India)
*Department of Botany, School of Life Sciences, Dr. B.R. Ambedkar University, Agra-282002 (INDIA)

*e-mail:
semchau@gmail.com
Received : 1. 2.2012; Revised : 2.3.2012; Published on line : 1.7.2012

  ABSTRACT

Abutilon indicum (L.) Sweet (Malvaceae) a perennial sub-shrub or shrub flowers throughout the year. Plants exhibited considerable variation in the floral density, number of pollen/plant, pollen viability, and percentage of fruit-set and seed-set in different seasons of the year. During the months of February, March, September, October and November with minimum and maximum temperature ranging between 11.9-35.6°C, the plants exhibited maximum number of flowers/plant (128±10- 140±13), pollen production (10740±125-12000±750/flower) and pollen viability (65.5±7.7-70.1±8.2%). Fruit-set (90±8.9- 5±9.1%) and seed-set (41.9±2.5-45.2±3%) was also significantly high. On the other hand, with the either reduction in temperature in the months of December and January i.e.7.3 and 20.7°C, or considerable increase in the months of May and June i.e. 42.9 and 43.6°C respectively, the plants exhibited considerable reduction in the number of flowers/plant (20±3- 15±2), number of pollen/flower (6120±108 - 5520±110), pollen viability (35.1±4.5-24.5±3.4%), fruit-set (20±3.5%-13±2.8 in June) and seed-set (28.25±2.5% -20.35±2.5).

Keywords : Abutilon indicum, temperature, floral density, pollen/flower, pollen viability, fruit-set and seed-set.

 

  Proteomics of angiosperm pollen

Inder S. Sheoran1 & Vipen K. Sawhney*
Department of Biology, University of Saskatchewan, Saskatoon, Sask., S7N 5E2, Canada
1Present address: Department of Biology, University of Toronto Mississauga, Missisauga, Ontario, L5L 1C6, Canada

*e-mail:
vipen.sawhney@usask.ca
Received : 31.05.2012; Published on line : 10.6. 2012

  ABSTRACT

Pollen grains are important players in the sexual reproduction process in seed plants since they carry the sperm cells for delivery to the female reproductive organ. In angiosperms, pollen are small, 2- or 3-celled structures which are highly desiccated and can be subjected to various biotic and abiotic stresses in an external environment. With major advancements in proteomic technologies, the proteome of mature pollen have been analyzed in some angiosperm specieswith the objectives of identifying proteins and their function in pollen. In nearly all studies, the major proteinsidentified include those involved in carbohydrate/energy metabolism, stress- and defenserelated proteins, signalling proteins, cytoskeleton proteins, and proteins with roles in cell wall metabolism and cell growth, protein synthesis, and protein turnover/degradation. Other proteins with designated roles in nucleic acid, amino acid and lipid metabolism, hormone- ignaling proteins, and pollen allergens were also identified. Although the development of the entire pollen proteome is work still in progress, the studies thus far have provided valuable insights into the strategies angiosperm pollen have developed for survival in an open environment, and for ready germination and pollen tube growth on compatible stigma of a flower.

Keywords : Pollen, pollen tube, proteomics, mass spectrometry

 

 
 

Effect of three chemical hybridizing agents on pollen fertility and yield parameters in arhar (Cajanus cajan L. var. Manak)

G. Singh*, H. K. Gupta** & R. K. Jain*
*Department of Botany, K.R. College, Mathura-281402 (Uttar Pradesh), India
** Department of Botany, M.P. Post Graduate College, Danta, Sikar-332702 (Rajasthan), India

**e-mail:
har_ish_80@yahoo.com
Received : 2.4.2012; Revised : 2.5.2012; Published on line : 1.7.2012

  ABSTRACT

Efficacy of three chemical hybridizing agents namely, surf excel (a popular detergent), benzotriazole and ethaphon was tested for inducing pollen sterility and hybrid seed production in arhar (Cajanus cajan L. var. Manak). Treatments with all the three chemicals induced pollen sterility ranging between 90-100%. However, these treatments caused significant reduction in various yield parameters. However, a single treatment with 0.5 and 1.0% w/v surf excel induced 92.4-96.3% pollen sterility associated with insignificant reduction in various yield parameters. These treatments also enhanced pod size and 100 seed weight. Thus, surf excel, a well known detergent can be effectively used for inducing significantly higher degree of pollen sterility without effecting yield and these male sterile plants can be exploited for hybrid seed production in pigeon pea.

Keywords : Cajanus cajan, surf excel, benzotriazole, ethrel

 

 
  Nectar Secretion Dynamics in some Raspberry and Blackberry Cultivars

Kilián Schmidt1, Zsuzsanna Orosz-Kovács1, Ágnes Farkas 2
1Department of Plant Systematics and Gebotany, University of Pécs. Ifjúság u. 6., 7624 Pécs, Hungary
2Institute of Pharmacognosy, University of Pécs Rókus u. 2., 7624 Pécs, Hungary

e-mail:
1schmidtk@freemail.hu, a2 gnes.farkas@aok.pte.hu
Received : 5.6.2012; Accepted : 20.6.2012; Published on line : 1.7.2012

  ABSTRACT

Several representatives of the Rosaceae family display a periodic nectar secretion pattern. Our research aimed at investigating patterns of nectar secretion in some raspberry (Rubus idaeus) and blackberry (R. caesius) cultivars, members of subfamily Rosoideae. Fifteen tagged flowers per cultivar were bagged and sampled hourly. Nectar volumes were measured with calibrated micro pipettes, sugar concentrations were determined by a hand refractometer. Both raspberries and blackberries secreted the highest volumes of nectar at the stage of pollen shedding, but in several cultivars nectar was foundin balloon stage and young flowers, as well as old flowers that have finished pollen shedding. In raspberries the highest nectar volumes were measured in the morning and late afternoon. In early afternoon nectar secretion either ceased or lowervolumes were measured. In the morning hours, nectar sugar concentration was low (around 10%), at noon and in early afternoon the secretory product became more concentrated (around 30%), and in the late afternoon the concentration was at medium level (20%). The examined two blackberry cultivars differed significantly in their nectar secretion dynamics. Cv. 'Hull' provided nectar continuously, while 'Arapaho' secreted hardly any nectar. Nectar volumes were higher in the morning compared to the afternoon and evening hours, whereas concentration values increased from the morning to the afternoon, and slightly decreased in the evening. The reported differences in the nectar secretion patterns can have a profound impact on the insect attraction of various raspberry and blackberry cultivars.

Keywords : insect attraction, nectar sugar concentration,
pollen shedding,
Rubus

 

 
 

Floral phenology of Buxus wallichiana Baill. – an endemic tree species of Northwest Himalaya

Eshan Sharma & Namrata Sharma*
Department of Botany, University of Jammu, Jammu (J&K)-180006

*e-mail: phyllanthus@rediffmail.com
Received & Accepted : 15.6.2012; Published on line : 1.7.2012

  ABSTRACT

Buxus wallichiana Baill. is a multipurpose evergreen, slow growing tree endemic to North-West Himalaya. The species forms populations at high altitude areas of Jammu province and supports a major cottage industry in J&K state, India(common  names Papri, Chikari). Populations of this species were tagged in Noori-chamb area of Poonch district of Jammu province. This area at an altitude 1824m amsl experiences heavy snowfall and an average temperature of 2.0Co -17.0Co during the winter months of December- February. Thereafter temperature starts rising and reaches its highest in June when the minimum and maximum temperatures recorded are 21.0oC and 31.0oC. The tree is monoecious. Male and female flowers are borne together in a dense inflorescence, in which a single female flower remains surrounded by 10.2 ± 0.14 (9-11) male flowers (Fig.1a). Each male flower consists of four basifixed stamens enclosed within five tepals. A female flower consists of five tepals enclosing a pistil comprising of a tricarpellary ovary and three styles each with a bifid stigma. Ovary is syncarpous, 3-loculed and in each locule 2 ovules are present. Floral buds starts appearing during the month of September, at a time, when some mature fruits are still present on the plant. Most of these buds remain closed, with only a few male flowers opening and showing protrusion of anthers during October-November. Rest all these buds remain dormant for 4-5months (October-February), when the area experiences  low temperature and snowfall. The male buds squashed during this period show either the presence of pollen or pmcs at arrested metaphase stage (Fig.1b). Flowers bloom in month of March with male flowers opening first. Peripheral male flowers open first in an inflorescence and 3-4 days thereafter male flowers surrounding the central female flower start opening, simultaneously, female flower also opens. Flowers in an inflorescence take 6-7 days to open up. During this period, the flowers are visited by some bees and other pollinators. By the end of April, in all the plants flowering phase is over and fruit set is initiated. Species thus has a long flowering phase spanning from September-April (8 months), of which 4-5 months are passed in a dormant phase.

Keywords : Buxus wallichiana, monoecy, ud dormancy, arrested metaphase.

 

 
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