Interaction of Elevated CO2 and Moisture Stress on Blackgram Growth and Yield.

An experiment was conducted with blackgram (Vigna mungo L. Hepper) cv T-9 in Open top chambers (OTCs) to assess the impact of moisture deficit and its interaction with two levels of CO2 (550ppm and 700ppm) on biomass and seed yield. At flowering stage moisture deficit was imposed by withholding irrigation. Both elevated CO2 levels improved the total biomass and the extent of improvement was 2.7% and 23.5% under irrigated conditions, while 9.0% and 26.1% under moisture stress conditions at 550ppm and 700ppm of CO2 respectively. Higher improvement in seed yield than biomass at both elevated CO2 levels was recorded and under irrigated condition the seed yield improved by 26.3% and 58.9% while under moisture deficit conditions by 9.0% and 34.7% at 550ppm and 700ppm respectively. Though moisture deficit reduced the total biomass, seed yield and HI at all CO2 levels, however the magnitude of reduction was less at elevated CO2 levels. The ameliorative effect of enhanced CO2 concentrations under moisture deficit condition was observed through better pod number in blackgram as compared with ambient control which reflected as higher seed yield.

Identification of Suitable Guar Genotypes for Summer Season of Semi-Arid Region.

Cluster bean (Cyamopsis tetragonoloba (L.) Taub.) is a nitrogen-fixing legume has been used as a green manure, forage and as a seed crop. Guar gum, extracted from the pods of the guar plant, is widely used as an emulsifier, thickener and stabiliser in food and cosmetics. Approximately 23% of the guar seed is the gum (galactomannin). With growing international demand for the guar gum, identification or development of suitable varieties for different agro climatic conditions along with high seed yield and quality gum is the pressing need of the hour. To address these issues five guar varieties were evaluated during summer for their yield potential along with biotic factors. The genotype RGC-1017 performed better for biomass, pod number and seed yield as well as showed resistance to cutworm disease. RGC-986 a long duration variety produced high vegetative biomass with good root and shoot system may serve as a dual purpose variety for fodder and seed.

Correlation and Path Analysis of Seed Yield and Yield Contributing Components of Blackgram (Vigna Mungo L. Hepper) Under Rainfed Condition from Andhra Pradesh, India.

Correlation coefficient and path analysis studies were carried out with seventeen parents (fourteen lines and three testers) resulting 42 F1 crosses for fifteen yield contributing component characters. The phenotypic and genotypic correlation analysis revealed that seed yield was highly significantly and positively correlated with number of branches, number of clusters, number of pods per plant, number of seeds per plant pod weight, total biomass and also highly significantly and positively correlated among themselves. Path coefficient analysis for seed yield revealed that significant phenotypic and genotypic direct effect with seeds per plant, 100 seed weight, harvest index, pod weight and number of clusters per plant. Hence selection for these characters may be carried out in the field and lab for overall yield improvement in blackgram.

Impact of CO2 Enhancement on Photosynthesis and Protein Profile - Response Studies with a CO2 Responsive Black Gram Genotype.

Black gram (Vigna mungo (L.) Hepper) var. IC-282009 - a highly CO2 responsive genotype for biomass and seed yield was grown in Open top chambers (OTCs) under three levels of CO2 i.e. ambient (390 ppm) and two elevated levels 550ppm and 700ppm to assess photosynthetic acclimation to elevated CO2. Net photosynthetic rate (PN), change in leaf soluble protein profile and leaf carbohydrate constituents such as total soluble sugars, reducing sugars and starch content in leaves was quantified at all three CO2 concentrations. Photosynthetic rate was enhanced by 78% and 30% at flowering stage with 550ppm and 700ppm CO2 as compared with ambient control. It was also observed a higher accumulation of starch, total soluble sugars and reducing sugars in leaves at elevated CO2 levels. However, the leaf protein content recorded a decrease and altered the profile of ploy peptides with enhanced CO2 levels. At elevated CO2 concentrations significant differences were observed in ploy peptide profile at vegetative and flowering stages, the intensity of 260 kDa poly peptide increased at vegetative stage, whereas 72 kDa polypeptide increased at flowering stage, while 52 kDa poly peptide decreased at both stages. Enhanced CO2 concentrations improved the PN though certain polypeptides of leaf protein are down regulated and necessitate further experimentation to confirm their involvement in responsiveness of the selected black gram genotype.

Studies on the utility of plant cellulose waste for the bioadsorption of crystal violet dye.

Several synthetic dyes employed in textile and food industries are discharged into aquatic environment. These visible pollutants in water damage environment, as they are carcinogenic and toxic to humans. The use of cost effective and ecofriendly plant cellulose based adsorbents have been studied in batch experiments as an alternative and effective substitution of activated carbon for the removal of toxic dyes from waste water. Adsorbents prepared from sugarcane baggase, were successfully used to remove certain textile dye such as crystal violet from an aqueous solution. The present investigation potentiate the use of sugarcane baggase, pretreated with formaldehyde (referred as Raw Baggase) and sulphuric acid (referred as Chemically Activated Baggase), for the removal of crystal violet dye from simulated waste water. Experiments were carried out at neutral pH with various parameters like dye concentration, temperature, contact time and adsorbent dosage. Efficiency of raw baggase was found better than chemically activated baggase for adsorption of crystal violet dye. The data obtained perfectly fits in the Freundlich adsorption isotherm.