Anatomy of Piper colubrinum Link.

Piper colubrimum exhibits dimorphic branching (orthotropic and plagiotropic shoots) as in many other Piper species. The stem exhibits anomalous secondary growth. The number and size of peripheral and medullary bundles show variations in the two types of shoots. Secondary growth occurs only in the peripheral bundles. In a mature stem (7 mm thickness), the average length and width of xylem vessel is 258 flm and 73.8 flm respectively, in peripheral bundles, whereas in medullary bundles it is 195 flm and 81.5 flm, respectively. Vessels are pitted with simple perforation plates. Tracheids have scalariform and annular thickening. Libriform unseptate fibres are also present. Comparative stem anatomy of P. nigrum and P. colubrimum shows similarities. However, the aerial and underground roots show variations especially in the number of vascular elements. Secondary thickening in root is comparable to that in dicots. The aerial roots undergo transformation in internal structure when they enter soil and grow as underground roots. &nbsp

Anatomy of Piper colubrinum Link.

Piper colubrimum exhibits dimorphic branching (orthotropic and plagiotropic shoots) as in many other Piper species. The stem exhibits anomalous secondary growth. The number and size of peripheral and medullary bundles show variations in the two types of shoots. Secondary growth occurs only in the peripheral bundles. In a mature stem (7 mm thickness), the average length and width of xylem vessel is 258 flm and 73.8 flm respectively, in peripheral bundles, whereas in medullary bundles it is 195 flm and 81.5 flm, respectively. Vessels are pitted with simple perforation plates. Tracheids have scalariform and annular thickening. Libriform unseptate fibres are also present. Comparative stem anatomy of P. nigrum and P. colubrimum shows similarities. However, the aerial and underground roots show variations especially in the number of vascular elements. Secondary thickening in root is comparable to that in dicots. The aerial roots undergo transformation in internal structure when they enter soil and grow as underground roots. &nbsp

Comparative rhizome anatomy of four species of Curcuma

The anatomy of rhizomes of four economically important species of Curcuma namely, C. longa (turmeric), C. aromatica (kasthuriturmeric), C. amada (mango-ginger) and C. zedoaria (yellow zedoary) were studied, Though all the species basically had similar anatomical characters, variations were nocticed in the number and arrangement of primary and secondary vascular bundles, orientation of endodermoid layer, number and shape of starch grains and curcumin cells. Maximum number and size of curcumin cells were found in C. longa. The endodermoid layer formed a continuous ring along with the pericycle in C. longa and was more or less circular in C. amada. But in C, aromatica and C. zednario, this layer was discontinuous and wavy in nature, In C. longa the meristematic layer was associated with true cambium with ray and fusiform initials, Apart from this, the number of compaoion cells was clirectly proportional to metabolic translocation and deposition of reserve substances which can be considered as identifying characters among the species

Comparative rhizome anatomy of four species of Curcuma

The anatomy of rhizomes of four economically important species of Curcuma namely, C. longa (turmeric), C. aromatica (kasthuriturmeric), C. amada (mango-ginger) and C. zedoaria (yellow zedoary) were studied, Though all the species basically had similar anatomical characters, variations were nocticed in the number and arrangement of primary and secondary vascular bundles, orientation of endodermoid layer, number and shape of starch grains and curcumin cells. Maximum number and size of curcumin cells were found in C. longa. The endodermoid layer formed a continuous ring along with the pericycle in C. longa and was more or less circular in C. amada. But in C, aromatica and C. zednario, this layer was discontinuous and wavy in nature, In C. longa the meristematic layer was associated with true cambium with ray and fusiform initials, Apart from this, the number of compaoion cells was clirectly proportional to metabolic translocation and deposition of reserve substances which can be considered as identifying characters among the species

Diversity analysis of released varieties of Indian cardamom using ISSR markers reveal narrowing genetic base

311-322Elettaria cardamomum Maton the small cardamom of commerce is a monotypic genus in India under the family Zingiberaceae. Genetic diversity studies using inter simple sequence repeat (ISSR) markers were conducted on a total of 13 released varieties of cardamom including selections and hybrids from different research stations in South India along with a popular variety Njallani and a wild relative Aframomum sps as checks. ISSR markers however, revealed relatively high level of genetic redundancy among the tested varieties with the exception of a few. Nonetheless, unweighted pair group method of arithmetic average (UPGMA) based cluster analysis of the similarity matrix differentiated all the varieties tested with the exception of two and segregated the wild relative Aframomum. Considerable reduction of polymorphism percentage was observed on exclusion of Aframomum while studying ISSR polymorphism which could be an indicator of the narrowing genetic base in the released varieties. Morphological data were compiled based on International Plant Genetic Resources Institute (IPGRI) cardamom descriptor and revealed moderate variability among the varieties. The results highlighted the requirement of molecular characterization of unutilized germplasm accessions, related wild species, and exotic relatives using specific molecular markers to help refine breeding efforts and introgression of new alleles for further improvement and enhancement of genetic base of cultivated cardamom

Report on association of plant parasitic nematodes in large cardamom (Amomum subulatum Roxb.) at Sikkim, Himalaya region of India: Plant parasitic nematodes in large cardamom in Sikkim

Large cardamom (Amomum subulatum Roxb.), is a major cash crop grown in Sikkim Himalaya region. The crop is found to be affected by many pests (insects and diseases); which hinders the production, productivity as well as quality of the produce. Based on symptoms in this crop, similar to nematode infestation, soil and root samples were collected from the rhizosphere of different large cardamom fields and analyzed for presence of nematodes. Laboratory analysis revealed the association of six nematode species with large cardamom viz., Meloidogyne incognita, Helicotylenchus spp., Hoplolaimus sp., Tylenchorhynchus  annulatus, Pratylenchus sp. and Macroposthonia spp., of which  Meloidogyne incognita and Pratylenchus sp. were recorded in roots also and the percentage of occurance was 59.09. Apart from Meloidogyne incognita, all other five nematode species were recorded for the first time in large cardamom. Helicotylenchus spp. was the dominant genera among the six genera with 50% occurrence, 61.56 % relative abundance and 60 nematodes per 200 cc soil