Macrosocial determinants of population health in the context of globalization

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55738/1/florey_globalization_2007.pd

Estimation of leaf area in wheat using linear measurements.

In order to find a rapid, reliable method for estimating leaf area in wheat, field experiments were conducted with three wheat (Triticum aestivum L.) cultivars viz. Sonera, Lok-1 and Raj-1555. On the basis of correlation and regression analyses, the product of length and maximum width (LW) was found to be the best independent variable for determining the leaf area. The Y intercept had little affect on leaf area calculation and hence leaf area in wheat can be calculated by the simple equation Y = 0.75 LW. During the entire growth period leaf area and leaf dry weight was closely correlated but the logarithmic equation fitted better than the linear equation. Leaf area and total plant weight did not show any significant linear correlation

Growth analysis using curve fitting method in early and late sown sunflower.

Effect of sowing time on productivity of sunflower was studied. Sunflower seeds were first sown in August (early) and the second sowing was done in September (late). Growth analysis was done at an interval of 5-6 days from germination to maturation. Growth was measured in terms of dry weight and leaf area. Various growth indices like RGR, RLGR, NAR, LAR, LWR, SLA, etc. were calculated. Cubic polynomial was the best fit for all the growth parameters. The dry matter accumulation, leaf area, leaf dry weight and leaf number were significantly more in late grown crop than early grown one. The rate of total dry weight, leaf area and leaf dry weight were higher in late grown crop as compared to early grown one. RGR, RLGR and NAR were higher in the late grown crop from the beginning, which gradually decreased later on, in both the crops. LAR was distinctly more in late grown crop between d 30-40. Changes in SLA were similar to LAR while LWR was more in the beginning and decreased afterwards. RGR showed more correlation with NAR and very low correlation with LAR in both the crops. Thus it is concluded that the late sown crop had better growth, but still, to obtain maximum productivity in sunflower, improvement in RGR and NAR is required

Source-sink relationships and grain weight at different positions within wheat spike.

The response in growth and final weight of grains from basal, middle and apical spikelets to increases in assimilate availability was studied by modifying source-sink relationships during the grain growth period in a wheat cultivar Lok-1. The source-sink relationship was altered in 1500 plants by removing spikelets in various positions i.e. either apical, middle or basal spikelets were pinched off on the day of anthesis. The final grain weight, grain growth rate and grain filling period (duration) was significantly affected by increasing the source capacity per grain by trimming i.e. removing some spikelets. The final grain weight was positively significantly correlated with grain growth rate while it was significantly but inversely correlated with grain filling duration. A clear effect of position of grain in spikelet and its (spikelet) position on the spike could be visualized. The results imply that there is a possibility that the availability of photosynthates is limiting and does not fully satisfy grain growth requirements. It is suggested that in this cultivar during post-anthesis period, grain yield is source limited

Molecular characterisation of Aspergillus flavus isolates from peanut fields in India using AFLP

Not AvailableAflatoxin contamination of peanut, due to infection by Aspergillus flavus, is a major problem of rain-fed agriculture in India. In the present study, molecular characterisation of 187 Aspergillus flavus isolates, which were sampled from the peanut fields of Gujarat state in India, was performed using AFLP markers. On a pooled cluster analysis, the markers could successfully discriminate among the ‘A’, ‘B’ and ‘G’ group A. flavus isolates. PCoA analysis also showed equivalent results to the cluster analysis. Most of the isolates from one district could be clustered together, which indicated genetic similarity among the isolates. Further, a lot of genetic variability was observed within a district and within a group. The results of AMOVA test revealed that the variance within a population (84%) was more than that between two populations (16%). The isolates, when tested by indirect competitive ELISA, showed about 68.5% of them to be atoxigenic. Composite analysis between the aflatoxin production and AFLP data was found to be ineffective in separating the isolate types by aflatoxigenicity. Certain unique fragments, with respect to individual isolates, were also identified that may be used for development of SCAR marker to aid in rapid and precise identification of isolates.Not Availabl