Rice landraces of Tamil Nadu –a review

India being a floristically diverse and genetically rich nation is endowed with huge rice germplasm collections. As per the vedic evidences, in olden days about 400 landraces of paddy had been in cultivation in Tamil Nadu which is an agrarian state of India. But due to the introduction of high yielding cultivars these landraces went out of cultivation leading to genetic erosion. However, a few hundreds of landraces are in cultivation in small pockets in Tamil Nadu. So it is our bound duty to conserve the available landraces, sort out the duplications and maintain the identity of the cultivars by the way of precise morphological, biochemical and molecular characterization for the valuable traits possessed by these landraces. According to ancient Tamil literature, some of these landraces are resistant to biotic and abiotic stresses while some others are known for their nutritional and therapeutic values in rice. Landraces of Tamil Nadu origin were extensively studied for their tolerance against abiotic stresses whereas the clinical validation of several of the landraces with nutritional and medicinal value is gaining importance in view of the growing interest of the consumers for a health conscious diet. In this context, traditional knowledge about the indigenous cultivars will help to explore the scientific basis of the nutraceutical values of the traditional cultivars by the plant breeders for sustaining food as well as the nutritional security and for overcoming the future challenges

A new high yielding black kolukattai grass variety CO 2 (Cenchrus setigerus) suitable for Pasture lands

Cenchrus setigerus is commonly known as black kolukkattai grass and is a herbaceous perennial pasture land grass. TNCS 265 is a selection from Kangayam local developed at Department of Forage Crops, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore. TNCS 265 had registered high biomass yield in Station Trials (38.9 t/ha), Multi Location Trials (50.5 t/ha) and in On Farm Trials (46.8 t/ha) which is 12.75, 21.3 and 19.7 per cent yield increase over the check CO 1, respectively. The culture TNCS 265 was promoted to All India Coordinated Research Projects on Forage Crops & Utilization trials during the year 2016 to 2018 and it was evaluated at nine locations in the South zone. Among the cultures evaluated, TNCS 265 registered a mean green fodder yield of 69.0 t/ ha than the national check CAZRI-76 (54.87 t/ha) and the qualifying variety IGFRI-96-706 (57.98 t/ha) which showed an improvement of 25.76 and 19.01 per cent yield increase over the check, respectively. It ranked first in green fodder yield in all three years of evaluation, under AICRP trials in south zone. It has the crude protein content of 8.18 per cent. The fibre fractions such as Acid Detergent Fibre (%) and Neutral Detergent Fiber (%) were comparatively lesser (42.5 & 64.17 %) than the national check CAZRI-76 (45.43 & 70.4 %) indicating higher digestibility and intake of green fodder of proposed entry. It was also evident from its higher value of in vitro Dry Matter Digestibility (55.47 %) than the national check CAZRI-76 (51.93 %). Hence, considering the stable performance of TNCS 265 (Cenchrus setigerus), it was proposed and released as black kolukkattai grass CO 2 for pasture land cultivation in the south zone of India during 2019 and notified as per Gazette Notification No. S.O. 99(E). dt. 06.01.2020 for general cultivatio

Light flavor asymmetry of polarized quark distributions in thermodynamical bag model

219-223polarized quark distributions x(x), x(x) and x[(x)-(x)] are evaluated in the kinematic range 0.01x<1.0 at an average value of the square of the four momentum transfer Q2=10 GeV2 using Thermodynamical Bag Model(TBM). Flavor decomposition of polarized quark distribution are evaluated as a function of x for up (u + )/(u+) and down (d+))/(d+) flavor in the kinematic range 0.033xQ2=2.5 GeV2 using TBM. The calculated values are compared with the theoretical predictions of the Chiral Quark Soliton Model (CQSM) and experimental results of J Lab E99117 and HERMES Collaboration

Connected power domination number of product graphs

In this paper, we consider the connected power domination number ($\gamma_{P, c}$) of three standard graph products. The exact value for $\gamma_{P, c}(G\circ H)$ is obtained for any two non-trivial graphs $G$ and $H.$ Further, tight upper bounds are proved for the connected power domination number of the Cartesian product of two graphs $G$ and $H.$ Consequently, the exact value of the connected power domination number of the Cartesian product of some standard graphs is determined. Finally, the connected power domination number of tensor product of graphs is discussed.Comment: 12 page

Metroglyph analysis of morphological variations in Sorghum germplasm collections

An experiment was conducted during kharif 2008, to assess the pattern of morphological variations through metroglyphtechnique in local land races of Sorghum collected from different parts of Tamil Nadu. Based on this technique, geneticvariability was evaluated for five characters viz., grain yield / plant (g), fodder yield / plant (g), grain size (g), 1000 grainweight and ear head compactness among 63 accessions. The mean values were used for plotting the accessions in agraph. All accessions were grouped into eight distinct groups, which differed amongst themselves. Group II was thelargest comprising 25 accessions followed by Group V having 13 accessions with moderate grain yield and fodder yield.Group VI consisted of 3 accessions with high yield and medium fodder yield besides moderate 1000 grain weight andear head compactness. Group VIII had 3 accessions classified into medium grain yield with high fodder yield consistingof compact ear head and bold grains. Land races are the primitive cultivars which are selected and cultivated by farmersfor many generations. Land races have more genetic diversity, wider adaptability and high degree of resistance to bioticand abiotic stresses and even respond to selection for high yield. In the present world of research, great strides in sorghumimprovement have been made by transforming the local land races into more productive forms through hybridization toevolve highly adapted hybrids. Since, sorghum is the dual purpose crop, the germplasm lines of Group III, VI, VII andV could be helpful in future breeding programme for achieving higher grain yield, yield components and fodder yield.The study, therefore, indicated the possibility of producing dual purpose sorghum hybrids by combining desirablegermplasm accessions

Rice landraces of Tamil Nadu –a review

17-29India being a floristically diverse and genetically rich nation is endowed with huge rice germplasm collections. As per the vedic evidences, in olden days about 400 landraces of paddy had been in cultivation in Tamil Nadu which is an agrarian state of India. But due to the introduction of high yielding cultivars these landraces went out of cultivation leading to genetic erosion. However, a few hundreds of landraces are in cultivation in small pockets in Tamil Nadu. So it is our bound duty to conserve the available landraces, sort out the duplications and maintain the identity of the cultivars by the way of precise morphological, biochemical and molecular characterization for the valuable traits possessed by these landraces. According to ancient Tamil literature, some of these landraces are resistant to biotic and abiotic stresses while some others are known for their nutritional and therapeutic values in rice. Landraces of Tamil Nadu origin were extensively studied for their tolerance against abiotic stresses whereas the clinical validation of several of the landraces with nutritional and medicinal value is gaining importance in view of the growing interest of the consumers for a health conscious diet. In this context, traditional knowledge about the indigenous cultivars will help to explore the scientific basis of the nutraceutical values of the traditional cultivars by the plant breeders for sustaining food as well as the nutritional security and for overcoming the future challenge

Collection and conservation of Sorghum landraces from Tamil Nadu

Landraces are the varieties nurtured and cultivated by the farmers through traditional method of selection over the decades. The “landraces” are the primitive cultivars grown by farmers and their successors since ancient times. The Directorate of Sorghum Research (DSR) has explored Tamil Nadu and collected 150 accessions during 2003-2010. DSR has collected important landraces during its exploration, among them are Deshi, Irungu cholam, Kaka cholam, Karareddu cholam, Kari cholam, Karuncholam, Karuppu irunggu, Kolumeddu cholam, Kovilpatti cholam, Makkatai cholam, Manjal cholam, Matthappu cholam, Nathu cholam, Nattu cholam, Pei (Thalaiviracham) cholam, Periya manjal cholam, Rasa vellai cholam, Sembavala irunggu, Sencholam, Senkatan cholam, Sevappu cholam, Sivappu irunggu, Tenkasi vellai, Vailkattu cholam, Valapoo sigappu cholam, Veettu cholam, Vella cholam, Vellai cholam, and Vellai nattu cholam are very important and traditionally grown by the farmers over the centuries. Maximum frequency of 16 vellai cholam and 14 each of sencholam and irungu cholam were found in the collections. The highest number of twenty-one accessions were collected from Coimbatore district followed by 19 from Karur district. Forage landraces are very common in these regions as food and fodder values of the crop are considered essential the botanical raceBicolor had the maximum frequency (60 acc.) followed by durra race (42 acc.). Tamil Nadu has both the primitive race bicolor and advanced race durra. Most of the accessions were collected during were from the rabi (post-rainy) season (79 acc.) followed by late-kharif season (42 acc.). The landraces were grown as sole crop (121 acc.) in many parts of the state and as mixed crop either with green gram, red gram, black gram, bengal gram, cowpea, lablab and Italian millet in some pockets