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.

Pachytene Karyology of Ipomoea biloba

Abstract: The entire haploid complement of the pantropical diploid (2n=30) Ipomoea species, I. biloba Forsk has been identified at pachytene stage employing criteria such as relative length, centromere position, nucleolar association, distribution and length of dark- and light-staining segments in the arms and chromomere number, size and pattern of distribution. The diagnostic features of the differentiated pachytene bivalents and the idiogram at this stage are presented. The advantages of pursuing karyological studies at pachytene over that at somatic metaphase in this species is brought out. From a comparative study of pachytene karyotypes of I. biloba and the earlier investigated I. crassicaulis with which it has been recently hybridized, homoeology of eight chromosomes could be adduced. The need for pachytene analyses in this inter-specific hybrid, other releated species and their hybrids is emphasized. Later stages of meiosis were found to be normal leading to formation of over 95% stainable pollen.

Mutation Breeding in Tropical Root and Tuber Crops

Abstract: Tropical tuber crops are a unique group of vegetables that can be grown on a wide range of soils from slightly acidic to saline and in climatic conditions from tropical to subtropical regions with limited inputs. But their improvement is limited mostly to clonal selection due to flowering and seed set related inhibitions. Very few of them like sweet potato flower regularly and facilitate the breeding through hybridization. Though cassava flowers in normal tropical conditions, their flowering is irregular and asynchronous. In few crops like arrowroot, Chinese potato and yam bean, the narrow genetic base hinders selection for new or improved traits. Hence, induced mutations could play a greater role in the improvement of these crops. The vegetative propagation nature of these crops except yam bean facilitates the easy fixing of characters. Attempts have been made for the improvement of these crops through induced mutations all over the world. A few varieties have been released in crops like sweet potato, taro, and cassava through mutation breeding. The mutation breeding in tropical root and tuber crops in India was initiated in 1960s at ICAR-Central Tuber Crops Research Institute. Highly six mutant varieties were released in sweet potato all over the world followed by taro (3 varieties) and cassava (2 varieties). In India, the first mutant variety in these crops was released in Chinese potato (Suphala).

Weighted Average Method in Evolving the Nutrient Status of Soils Under Cropping Systems Involving Tuber Crops in AEU 3 and AEU 9 of Kerala

Abstract: Agro ecological unit (AEU) 3 and AEU 9 are the two major tuber crops growing regions of Kerala cultivating tuber crops like cassava, yams and aroids mostly as intercrops in coconut gardens. Nutrient status of the soils of AEU’s are determined for making proper fertilizer recommendation to avoid both under-use and over-use of nutrients thereby attaining monetary gain as well as soil health protection by avoiding excess nutrient application. In arriving at proper nutrient status of the soils of the AEU’s, determining the weighted average nutrient status of the AEU’s with respect to the mean nutrient status and area of the panchayats/blocks was found better. It can be more meaningful and realistic from the point of view of arriving at the fertilizer recommendation to crops cultivating in that AEU’s. In this paper, as a prelude to formulate customized fertilizers for elephant foot yam (EFY) under intercropping in the coconut gardens of these two AEU’s, the weighted average data on pH, EC, organic carbon (OC), available N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn and B based on the nutrient status of the soils collected from 43 and 161 panchayats and their respective areas under AEU 3 and AEU 9 were determined. The values for AEU 3 and AEU 9 respectively were 5.85 for both AEU’s (pH), 0.291 and 0.310 dSm-1 (EC), 0.945 and 1.502% (OC), 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 ppm (exchangeable Mg), 5.07 and 21.46 ppm (available S), 3.94 and 5.68 ppm (available Zn), 0.698 and 0.816 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). The weighted average data of the two AEU’s indicated drastic variation in the nutrient status between the two AEU’s in the case of most of the parameters. The weighted average nutrient data of the two AEU’s clearly indicated the suitability of the soils of both AEU’s for EFY cultivation especially AEU 9 as they are rich in organic carbon as well as other essential nutrients. Moreover, this data formed a basis for fixing the theoretical optimum of soil test based nutrient recommendation to derive the practical optimum based on nutrient omission and nutrient level experiments in formulating the customized fertilizers for EFY.

Genetic Variability and Character Association in Taro (Colocasia esculenta (L.) Schott.) Under Mid-Hills of Arunachal Pradesh

Abstract: An experiment was conducted to screen the superior taro genotypes and to identify the genetic divergence of quantitative characters under mid-hill conditions of Arunachal Pradesh. Fourteen taro genotypes were studied for their morphological, growth and yield characters. Taller plants were observed in APTC-1 (120.7 cm) followed by APTC-2. APTC-5 and TRC-2, which were on par in plant girth (17.8 cm) whereas greater number of suckers was seen in APTC-4 (4.5). Number of leaves (4), leaf area index (1.1-1.6), lamina length (24.8-37.2 cm) and breadth (17.8-28.6 cm) were more in APTC-2,APTC-7, APTC-1 and APTC-6 respectively. Cormel yield was significantly higher in APTC-5 (16.1 t ha - 1 ) followed by Muktakeshi (15.1 t ha -1 ), APTC-1 (15.0 t ha -1 ) and APTC-2 (14.5 t ha -1 ), which were on par. The high value of Phenotypic Coefficient of Variation (PCV) along with Genotypic Coefficient of Variation (GCV) indicated that there was more variability in the characters like plant girth, number of side suckers, number of cormels and cormel yield. The high values of genetic advance (GA) coupled with high estimates of heritability suggest that real progress in improvement through selection could be made for yield and associated traits like number of leaves, lamina length and breadth, cormel weight and cormel size. The genotypes APTC-1, 2 and 5 and TRC-2 and 3 could be used for further breeding programmes.

Effect of protein enrichment on quality characteristics and glycemic index of gluten free sweet potato (Ipomoea batatas L.) spaghetti

Abstract: The aim of present investigation was justifying the suitability of sweet potato flour for development of gluten free spaghetti with reduced starch digestibility and to enhance protein content by fortification of whey protein concentrate (WPC) and chickpea flour (CPF) at the rate of 5%, 10%, and 15% respectively along with control. The effect of fortification in spaghetti was assessed for its glycemic index, physical, nutritional, and sensory properties. The data revealed that increase in the level of fortification of WPC and CPF resulted with increase in optimum cooking time, weight and volume without affecting cooking loss as compared to control sample. The percent increase in protein content of spaghetti fortified with WPC and CPF found as 192.20% and 150.08% respectively in comparison with control. However, spaghetti fortified with 15% CPF and 15% WPC showed lowest starch digestibility with reduced glycemic index to 59.43 and 58.73 respectively. The spaghetti fortified with 10% WPC and 10% CPF was found overall acceptable by panelists. Moreover, the fortification of spaghetti with WPC and CPF could significantly increase the protein content along with overall acceptability and functional characteristics.