Central Tuber Crops Research Institute

About: Central Tuber Crops Research Institute is a facility organization based out in Thiruvananthapuram, Kerala, India. It is known for research contribution in the topics: Starch & Fermentation. The organization has 475 authors who have published 587 publications receiving 10285 citations.

Molecular Profiling of Landraces of Cassava (Manihot esculenta Crantz) Using ISSR Markers

Abstract: Six accessions of cassava viz., C1 (Narrow leaved - MNS-13-1), C2 (Devan Kappa - SRA-13-1), C3 (Pullad Kappa - MNS-13-5), C4 (Karutha Malabar), C5 (MNS-AICRP) and C6 (Pullad Kappa) maintained in the field genebank of Central Tuber Crops Research Institute, Sreekariyam, Thiruvananathapuram were subjected for molecular analysis using 5 selected ISSR primers. UBC 808 produced highest number of bands (12) and UBC 817 produced the lowest number of bands (3) while UBC 845 is not amplified. The percentage polymorphism of the ISSR primers studied ranged from 33.3% - 100%. UBC 817 recorded the lowest polymorphism (33.3%) and UBC 808 recorded the highest Polymorphism (100%). The similarity coefficient based on ISSR markers ranged from 0.55 to 0.86. The dendrogram generated using UPGMA cluster analysis separated the 6 accessions of cassava in to 3 major groups with 2 accessions each. The accessions C1 (Narrow leaved - MNS-13-1) and C5 (MNS-AICRP) formed a ball cluster with 86% genetic similarity were found to be highly related. Likewise, C3 (Pullad Kappa - MNS-13-5) and C4 (Karutha Malabar) also formed a ball cluster showing 86% genetic similarity. C3 (Pullad Kappa - MNS-13-5) and C4 (Karutha Malabar) recorded 80% genetic relatedness with C1 (Narrow leaved - MNS-13-1) and C5 (MNS-AICRP). Likewise, C2 (Devan Kappa - SRA-13-1) and C6 (Pullad Kappa) also showed 80% genetic similarity with each other. C2 (Devan Kappa - SRA-13-1) and C6 (Pullad Kappa) recorded only 67% genetic relatedness with C3 (Pullad Kappa - MNS-13-5), C4 (Karutha Malabar), C1 (Narrow leaved - MNS-13-1) and C5 (MNS-AICRP). However, the two accessions C3 and C6 of the landrace Pullad Kappa got separated with only 67% genetic similarity. The dendrogram generated grouped the accessions and species on the basis of Nei genetic distance using unweighted pair group method with arithmetic average (UPGMA) cluster analysis. The results of the study indicated that the primers selected for the present study will be useful for future genetic analysis of cassava germplasm and hence provide breeders with a genetic basis for selection of parent for crop improvement programs.

Evaluation of White-fleshed Sweet Potato Clones for Storage Root Yield and Dry Matter Content

Abstract: Sweet potato (Ipomoea batatas (L.) Lam.) is an important vegetatively propagated crop cultivated for its edible storage roots. It produces the highest energy (194 MJ ha day) and considerable yield with low inputs even in marginal lands (Woolfe, 1992). The storage roots and young leaves are used as a vegetable. The flesh colour of the storage roots varies from white to different shades of cream and yellow to dark orange depending on the carotene content. However, the white-fleshed sweet potatoes, which have no β-carotene content, are traditionally grown and preferred by the local population all over India. The choice of sweet potato variety is strongly correlated with the dry matter and starch content (Simmone et al., 1993). The present study was undertaken to assess the storage root yield and dry matter content of promising white-fleshed sweet potato clones identified from the poly-cross breeding programme.

Assessment of Variability in Sweet Potato (Ipomoea batatas (L.) Lam.) Germplasm Using Morphological and ISSR Markers

Abstract: Fifty two accessions of sweet potato collected from eastern states of India and maintained in the National Active Germplasm Site at ICAR-CTCRI, along with two wild species Ipomoea triloba L. and Ipomoea aquatica Forssk. were evaluated using eighteen vegetative morphological and eleven Inter Simple Sequence Repeats (ISSR) markers. The dendrogram obtained using phenotypic characters separated the genotypes into two major clusters and an outlier at a Euclidean distance of 1.20. The first three principal components of data accounted for 67.50% of the total variance among accessions. Traits like predominant vine colour, leaf lobes type were found to be of great importance in distinguishing the accessions. The cluster diagram based on morphological data revealed that the accessions exhibited greater degree of genetic variation for the 18 different morphological traits observed. According to the morphological data, there were no duplicate accessions and S1439 and S1442 were found to be highly similar among the accessions studied. The hierarchical clustering using on ISSR profile based on Jaccard’s similarity coefficient separated the accessions into three principal clusters at a similarity coefficient of 0.56. The first principal cluster consisted of 37 accessions with many sub-clusters showing high intra-clusteral variability indicating the variability in the sweet potato accessions selected for the study. Accessions collected from the same geographical area were grouped together in a single cluster. The second principal cluster comprised of 15 accessions with one set of two accessions showing 89% similarity, both collected from Bihar. This grouping was similar to that obtained with morphological data. I. triloba L. and I. aquatica Forssk. were grouped as a third cluster showing their species specificity. Mantel test indicated significant correlation between morphological and molecular marker information.

Optimum Nutrient Requirement of Elephant Foot Yam (Amorphophallus paeoniifolius (Dennst.) Nicolson) Under Coconut Gardens

Abstract: Among the tropical tuber crops, elephant foot yam (EFY) ( Amorphophallus paeoniifolius (Dennst.) Nicolson) is a highly potential and ideal intercrop for the coconut gardens of Kerala. Being highly efficient biologically with good yield potential to the tune of 30-100 t ha-1, it is high nutrient demanding too. Though, there are different nutrient management approaches for the cultivation of this crop, taking into account both crop productivity as well as soil health, balanced nutrition based on soil nutrient status and crop requirement deserves special mention. In this regard, customization of nutrients specific to regions and crops can be considered as one of the key approaches. In the protocol for arriving at the grades of the customized fertilizer formulations, one component is evolving the actual optimum of all nutrients of a particular soil by conducting nutrient omission experiments for major nutrients and nutrient level experiments for secondary and micronutrients. Such experiments were conducted for elephant foot yam under intercropping in coconut gardens of the major tuber crops growing soils of Kerala viz., laterite (AEU 9) and sandy plains (AEU 3). The theoretical optimum (based on weighted average data of the soil test) was N : P : K : Mg : Zn : B : Dolomite @ 71 : 12.5 : 106.5 : 16 : 5.25 : 1.31 : 1000 (AEU 3) and 78 : 12.5 : 90 : 16 : 5.25 : 1.31 : 1000 kg ha-1 (AEU 9) respectively. The weighted average data of nutrients was 0.95 and 1.50% (organic carbon), 61.97 and 69.27 kg ha-1 (available P), 213.96 and 295.87 kg ha-1 (available K), 113.32 and 600.16 ppm (exchangeable Ca), 37.53 and 114.99 (exchangeable Mg), 5.07 and 21.46 ppm (available S), 3.94 and 5.68 ppm (available Zn), 0.70 and 0.82 ppm (available B), 1.79 and 3.79 ppm (available Cu), 101.20 and 64.66 ppm (available Fe) and 18.82 and 37.65 ppm (available Mn) respectively for AEU 3 and AEU 9. Different sub optimal and super optimal levels of the theoretical optimum of nutrients viz., N,P, K, Mg, Zn, B and Dolomite was kept as treatments for conducting these experiments in the two locations of AEU 9 and one location in AEU 3. Based on the corm yield data from these experiments, the actual optimum derived by conducting the NOP (Nutrient Omission Plot) and NLE (Nutrient Level Experiment) was N: P: K: Mg: Zn: B: Dolomite @ 140: 20: 225: 19.2: 4.2: 1.575: 1500 kg ha-1 for AEU 3 and 160:12.5:180: 19.2:6.3:1.975:1500 kg ha-1 for AEU 9 respectively and these experiments formed the basis for calculating the different nutrient use parameters for arriving at the grades of the customized fertilizer formulations.

Characterisation of the Macluraviruses Occurring in India

Abstract: The genus Macluravirus of the family Potyviridae currently contains six recognized and two tentative virus species. In India, so far only two macluraviruses eg., large cardamom chirke virus (LCCV) and cardamom mosaic virus (CdMV) infecting large cardamom (Amomum subulatum) and small cardamom (Elettaria cardamomum), respectively have been studied well. Recently, a new macluravirus, yam mottling virus has been tentatively identified in mild mosaic disease of yam (Dioscorea spp) in southern India. LCCV is distributed in large cardamom cultivated in the North-East sub-Himalayan mountains and CdMV in small cardamom cultivated in southern India. Both these macluraviruses cause chlorotic streak mosaic disease in cardamom. CdMV and LCCV are known in India since long time and considerable infromation has been generated. This chapter summarizes the work on the biological and molecular properties of macluraviruses occurring in India.