Mycorrhizal association of Ochlandra travancorica in Kerala, India

and Ranni. It prefers diffused light, requires annual rainfall of more than 1500mm and good drainage for its luxuriant growth. The perfect growth and regeneration of these valuable plants in its restricted habit and habitat is presumed to be because of certain microbes, especially mycorrhizal fungi. Materials and Methods: The feeder roots and rhizosphere soil samples of Ochlandra travancorica were collected from four sites (Bonacaud, Kottoor, Kulathupuzha and Palode) of Kollam and Thiruvananthapuram districts in Kerala in July 2011. Four soil samples were taken from each site up to the depth of 20cm and prepared into one composite sample (ca. 500gm). The soil was screened to isolate Arbuscular Mycorrhizal (AM) fungal spores by wet-sieving and decanting technique and the count expressed as spores per 100g of soil (Gerdemann & Nicolson 1963). Terminal feeder root samples collected from a different area was processed separately; washed in running tap water, cut into small pieces about 1cm, boiled in 10% KOH (w/v) for one hour, cooled to room temperature, washed thoroughly in distilled water, stained in lactophenol cotton blue (Philips & Hayman 1970). They were observed under a binocular microscope to locate vesicles and arbuscules to evaluate the percentage of mycorrhizal colonization.

of Thiruvananthapuram, Thenmala and Ranni.It prefers diffused light, requires annual rainfall of more than 1500mm and good drainage for its luxuriant growth.The perfect growth and regeneration of these valuable plants in its restricted habit and habitat is presumed to be because of certain microbes, especially mycorrhizal fungi.
Materials and Methods: The feeder roots and rhizosphere soil samples of Ochlandra travancorica were collected from four sites (Bonacaud, Kottoor, Kulathupuzha and Palode) of Kollam and Thiruvananthapuram districts in Kerala in July 2011.Four soil samples were taken from each site up to the depth of 20cm and prepared into one composite sample (ca.500gm).The soil was screened to isolate Arbuscular Mycorrhizal (AM) fungal spores by wet-sieving and decanting technique and the count expressed as spores per 100g of soil (Gerdemann & Nicolson 1963).
Terminal feeder root samples collected from a different area was processed separately; washed in running tap water, cut into small pieces about 1cm, boiled in 10% KOH (w/v) for one hour, cooled to room temperature, washed thoroughly in distilled water, stained in lactophenol cotton blue (Philips & Hayman 1970).They were observed under a binocular microscope to locate vesicles and arbuscules to evaluate the percentage of mycorrhizal colonization.
H′= Σ (n i / Nlog e n i / N) where, n i is the importance value of each species and N is the total importance value.
where n i is the number of individuals of each species and N is the total number of individuals in that location.
The fungal spores were identified with the help Schenk & Perez (1990).

Result
Hyphal structure: The root samples exhibited the presence of extensive hyphal and vesicular stages of AM fungal colonization and the colonization varied from 42-72 %.The extra-radical hyphae were hyaline and dichotomously branched on root epidermis to form an appressoria.The hyphae on the root were hyaline to yellowish-brown, thick-walled, aseptate, growing inter and intra cellularly through the cortex and had penetrated the inner cortex.The hyphal coils were observed in root cortex and globose to subglobose terminal vesicles (25-37 × 25-40 µm; Image 1b) were observed in the cortex cells.
Spore count: Arbuscular mycorrhizal fungi were found to be present in all the sampling sites in this study and spore count was 272-348 spores per 100g soil (Fig. 1).A total of nine species, namely, Claroideoglomus etunicatum, Glomus aggregatum, G. boreale, G. macrocarpum, G. multicaule, G. tortuosum, Sclerocystis clavispora, S. rubiformis, S. taiwanensis were isolated from the different sampling areas.Among these, G. aggregatum, S. clavispora and S. rubiformis were common to all the sites.
The frequency of occurrence of mycorrhizal species associated with O. travancorica varied from one locality to another (Table 1).G. aggregatum, S. clavispora and S. rubiformis were found in all the locations of the study; whereas, incidence of G. macrocarpum was 75% and G. boreale, G. tortuosum and S. taiwanensis was 50%, Claroideoglomus etunicatum and G. multicaule showed 25% of frequency.Species richness also varied.Kulathupuzha harboured more number of species than the other study localities.Simpson's diversity index (Ds) and Shannon's diversity index (Hs) was in the range of 0.6-0.8 and 2.8-4.4,respectively.
Physiochemical characters of soil: The pH of O. travancorica rhizosphere soils collected from the study sites was 3.9-5.6.The level of phosphorous was very low.The physiochemical characters of soil samples are in the Table 2 Chlamydospores formed in loose clusters, without peridium, hyaline to yellow, globose, subglobose, obovate, cylindrical to irregular, 40-90 x 45-110 µm; wall yellow to yellowish-brown, up to 2µm thick, outer walls slightly thicker and lighter in colour than the inner wall; walls separable with slight pressure.Subtending hyphae at the point of attachment was 4-10 µm wide, straight to sharply curved at the spore base.Pore usually open, 2-5 µm wide, often closed by a thin curved septum, cytoplasmic plug or spore wall thickening but not by hyphal wall thickening.
Chlamydospores slightly longer than wide, globose, subglobose to irregular, 98-130 x 98-130µm.Spore wall composed of two layers, outer layers thin up to µm thick; inner wall layer yellow, 6-10 µm thick.Spores taper to the point of attachment, hypha single, persistent, 12µm broad at this point of attachment, inner wall occlude the pore of the attached hyphae, and the wall thickening continuous in to the subtending hyphae for up to 75µm from the spore.Pore closed by a septum.Spores characteristically bear straight, long subtending hyphae which may extend up to 100µm before branching.
Sporocarps unknown; chlamydospores dark brown, 142-240 x 125-150 µm in diam., ellipsoidal, broadly ellipsoidal, subglobose to occasionally triangular, with 1-4 hyphal attachments, attachments generally occurring at opposite ends of the spore.Spore wall 8-22 µm thick, thickest at the point of hyphal attachments, rounded projections 1-3 µm long, evenly distributed over the wall surface.Sporocarps unknown, chlamydospores formed singly or in pairs in soil, immature spores subhyaline, without hyphal mantle.Matured spores yellow to dull greyishbrown with a mantle of sinuses hyphae closely apprised to the spore and flattened, 4-10 µm wide, forming a layer of hyphae on the spore surface, up to 20µm thick, occasionally mantle extended down to the hyphal attachment.Mantle hyphae hyaline when young, acquiring a brownish pigment with age and originating from the swelling on the hyphal attachment, 10-20 µm below the spore or arising from the other hyphae adjacent to the spore.Mantle adhered with debris and soil particles.Chlamydospores globose to subglobose, 120-210 µm (excluding mantle); spores with single laminate thin wall less than 1µm.The width of hyphal attachment at the spore base is 8-20 µm, hyaline to light yellow.

Sclerocystis taiwanensis
Sporocarps globose, brown to dark brown, 190-250 x 190-250 µm in diameter.Chlamydospores formed radially in a single, tightly packed layer around the central plexus of hyphae, clavate to cylindrical, cinnamon brown, 65-80 µm long, 28-32 µm broad at the upper portion, 9-18 µm broad at the lower portion, with or wit out septum at spore base.Wall two-layered, external one thin and hyaline, inner layer brown, apical portion of the wall deep golden brown, 9-13 µm thick, 2-3 µm thick laterally.Central portion pale yellow and typically distinct from the wall.Stalk pale brown, continuous, 9-22 x 2-4 µm, central plexus up to 70µm in diameter.
and rhizosphere soil samples of the Reed Bamboo Ochlandra travancorica were collected in July 2011 from different localities in Kollam and Thiruvananthapuram districts of Kerala State.Composite soil samples (Soil pH 3.9-5.6.)revealed the presence of nine AM fungal taxa, namely, Claroideoglomus etunicatum, Glomus aggregatum, G. boreale, G. macrocarpum, G. multicaule, G. tortuosum, Sclerocystis clavispora, S. rubiformis and S. taiwanensis.Root colonization was 42-72 % and extensive hyphal and vesicular stages were observed.The extra-radical hyphae were hyaline and dichotomously branched on root epidermis showed appressoria.The hyphal coils were observed in the cortex cells.

Spores per 100gms of soil Percentage of mycorrhizal colonization
. Ochlandra travancorica, Kulathupuzha, coll.P.P. Rajesh Kumar (TBGT slide no.1020).Chlamydospores formed singly in soil or in dead roots, adherent to debris, globose to subglobose, 70-135 µm in diam., wall smooth to roughened.Spore wall 4-10 B o n a c a u r d K o tt o r K u l a t h u p u z h a P a l o d e Spore count / 100g spoil Root colonization Figure 1.