Optimization of Size and Shape of Experimental Plots for Trials Against Eggplant Fruit Borer,Leucinodes orbonalis Guen 1

Studies were made to work out the optimum size and shape of the plots for conducting field trials against Leucinodes orbonalis Guen which is a serious pest of eggplant throughout South East Asia and Africa. A plot with 20 plant stand measuring 7.2 m² was found to be optimum size based on the cv.-% values. The shape of the plot was not considered to be important. The index of infestation heterogeneity (b) was high (> 2) indicating uniform spread of infestation throughout the field.     

Effect of Deep Placement of Slow-release Fertilizer (Lime Nitrogen) Applied at Different Rates on Growth, N2 Fixation and Yield of Soya Bean (Glycine max [L.] Merr.)

A new fertilization method with deep placement of slow‐release N fertilizers, such as coated urea and lime nitrogen (LN) (calcium cyanamide) at 20 cm depth was found to promote soy bean seed yield. In the present study, the effect of deep placement of LN was investigated on different parameters such as growth, N accumulation, N₂ fixation activity and yield of soy bean by applying LN at different rates in the rotated paddy field of Niigata, Japan. In addition to the basal fertilizer, ammonium sulphate (16 kg N ha^?1), deep placement of LN was conducted by applying various amounts such as 50 kg N ha^?1 (A50), 100 kg N ha^?1 (A100) and 200 kg N ha^?1 (A200) at 20 cm depth in separate plots. A ¹⁵N‐labelled LN fertilizer was also employed for each of the above treatments to calculate N utilization from LN in separate plots. Soya bean plant growth and N₂ fixation activity were periodically analysed. Both plant growth and N accumulation were found to increase with LN treatment compared with control plants. An increase in N₂ fixation activity was found in the A100 plots. The total seed yield was the highest in the deep placement of LN with A100 (73 g per plant) compared with other treatments. The visual quality of harvested seeds also showed that A100 enhanced the quality of seeds compared with other treatments. Thus, it is suggested that N fertilization management with particular reference to optimum amount of fertilizers is important for maximum growth, N₂ fixation and enhancement of seed yield of soy bean.     

An analysis of the appropriateness of wind and other energy systems for irrigation water pumping in India

This study attempts to quantify a figure of merit (appropriateness) for various options of energy technologies feasible for a prespecified task. Within the framework of rural energy development, various attributes are identified, relatively weighted and quantified for a group of energy technologies including renewable energy sources. Based on the data for Indian conditions, it is found that windmills designed to respond to low wind speeds of the order of 12 km/h and very carefully optimised for cost reduction are likely to be most appropriate within the group of alternatives considered in this study. This conclusion, however, holds only for irrigation from shallow wells (10–15 m deep) in small farms (size 1–2 ha).     

Characterization and identification of leaf morphology of <Emphasis Type="Italic">Populus deltoides</Emphasis> Bartr. clones

Leaves are of fundamental importance to plants, representing their facility to generate power and are the sensing units of plants towards the environment. An attempt was made to characterize and compare the variations of leaf morphology of various Populus deltoides Bartr. clones by studying the winter buds and other leaf parameters of fully developed leaves. To achieve these objectives, forty-three exotic and indigenous clones of P. deltoides Bartr. were evaluated for different parameters. On the basis of various morphological characteristics the results reveal that each clone has a distinct color pattern of leaves. Different colors observed in these clones varied from light green through green to dark green. Two distinct lengths of the leaf apex were found, i.e., short and long; as well both acuminate and acute apex types were found. Erratic distribution of serration of leaves was also found. In this study, the morphological traits of leaves provided discriminatory grounds for separating various populations of P. deltoides Bartr. clones. Winter bud studies indicate that different clones vary considerably with regard to shape, color, shape of leaf scars and exudation.     

Amplified Fragment Length Polymorphism (AFLP) Based Genetic Diversity Studies in Betel Vine (Piper betle L.)

Betel vine has been identified as an important cash crop in India. It is a vegetatively propagated plant and more than 100 landraces (cultivars) are cultivated in India. They are often named after the localities where they are grown. To assess the molecular genetic diversity among 10 betel vine cultivars, amplified fragment length polymorphism (AFLP) markers were used. Five AFLP primer combinations produced 323 bands of which 155 were polymorphic, leading to a 47.99% polymorphism. Average polymorphic information content (PIC) was 0.14 over all primer combinations. Genetic similarity was calculated from the Jaccard's similarity coefficient (r) value for all accessions which varied from 0.39 to 0.81, with an average of 0.60 implying a medium level of genetic variation between investigated cultivars. Cluster analysis divided the cultivars into two main clusters where M2 and M3 were closely related but F3 was separate from all others. The cluster analysis based on AFLP data indicated that cultivars were not grouped according to their geographic place of collection but rather by genetic relatedness. The principle coordinate analysis (PCA) of the markers was linked to the dendrograms generated by employing UPGMA.     

Stress Studies in Lentil (Lens esculenta Moench)

A pot experiment was conducted to see the effect of varying levels of soil sodicity on leaf growth, nitrate reductase activity, nodule development and nitrogenase activity in two lentil ( Lens esculenta Moench) genotypes. It was observed that in both the genotypes increasing level of soil sodicity decreased the plant height, leaf area, leaf dry weight, total biomass production and finally the grain yield. Nitrate reductase activity in leaf tissues and concentration of total nitrogen in different plant organs showed significant reduction with increase in soil sodicity. Increasing soil sodicity (15 and 20 ESP) was not only deleterious to nodulation and nitrogenase activity but also caused complete failure of nodulation process at 25 ESP of soil. Reduction in aforesaid characters due to increasing soil sodicity was less in variety PL-406 than that of local indicating thereby the relative tolerance of PL-406 to sodicity.
Prolonged and higher activities of nitrate reductase and nitrogenase at higher sodicity level in PL-406 might be the reasons for superiority of this variety. Significant and positive correlations were also observed between leaf characters and nitrogenase activity.     

Histopathological Study of Barley Cultivars Resistant and Susceptible to Rhynchosporium secalis

ABSTRACT Differences in the penetration process by Rhynchosporium secalis were compared in resistant and susceptible barley cultivars at the seedling stage. Percent penetration and percent host cell wall alteration (HCWA) differed significantly among cultivars and isolates as revealed by light microscopy. Based on these two variables, the cultivars were statistically separated into two groups that corresponded to their disease reactions. The resistant cultivars, Johnston and CDC Guardian, showed 81.2 to 99.4% HCWA and 0.1 to 20.1% penetration at encounter sites, whereas the susceptible cultivars, Harrington, Argyle, and Manley, had 30.1 to 78.3% HCWA and 31.8 to 81.8% penetration. In the current study, cv. Leduc, which is susceptible at the seedling stage and resistant at the adult stage, showed the same percent HCWA and penetration as did susceptible cultivars. A significant negative correlation (P < 0.01) was found between percent penetration and percent HCWA for cultivars inoculated with two isolates of the pathogen. Isolate 1 was less virulent than isolate 2 with respect to percent penetration and induced significantly fewer HCWA. Scanning electron microscopy showed various shapes of fungal appressoria but no apparent difference in host reaction between resistant and susceptible cultivars. Transmission electron microscopy revealed interactions between the host and pathogen at various stages of penetration. The resistant cv. Johnston responded by producing appositions, as evidenced by a layer of compact osmiophilic material deposited on the inner side of the cell wall. Infection pegs produced by conidia were unable to penetrate the cuticle where an apposition had formed inside. When penetration occurred in the susceptible cv. Argyle, cytoplasmic aggregates and separation of the plasmalemma were visible from the host cell wall, but the layer of compact osmiophilic material was not always present. Data based on light microscopic observations suggested that HCWA may be one of the mechanisms responsible for resistance that is characterized as penetration prevention rather than as a slow rate of mycelial growth after successful penetration. HCWA occurred in response to attempted cuticle penetration, suggesting that HCWA may produce chemical barriers that help to prevent penetration.     

Ploidy manipulation in guinea grass (Panicum maximum Jacq., Poaceae) utilizing a Hybridization-supplemented Apomixis-components Partitioning Approach (HAPA)

Ploidy manipulations are achieved by utilizing unreduced gametes, somatic chromosome doubling or haploidization. Apomixis, the asexual mode of reproduction through seeds, involves two of these phenomena viz., apomeiosis (unreduced embryo-sac formation) and parthenogenesis (fertilization-independent embryogenesis). The two components when partitioned may yield high frequencies of triploids and haploids, and thus, serve as a tool to manipulate ploidy levels when appropriately supplemented with hybridization schemes. Utilizing this H ybridization-supplemented A pomixis-components P artitioning A pproach (HAPA), the largest ploidy series in a crop plant was generated in guinea grass ( Panicum maximum Jacq.). Eighty-nine diverse guinea grass accessions were characterized for their reproductive capacities to identify tetraploid (2 n  = 4 x  = 32) accession(s) with high apospory but reduced parthenogenetic capacity, thereby producing a high frequency of hexaploid seeds. Seeds from accession IG 04-164 were utilized to produce a ploidy series by appropriately combining partitioned apomixis components and hybridizations in two seasonal cycles. We successfully obtained plants representing ploidies 3 x, 4 x , 5 x , 6 x , 8 x and 9 x , all derived from a single 4 x progenitor. Production methodology, reproducibility and utilization of HAPA in cytogenetic and molecular studies are discussed.     

Quantification of saccharides in multiple floral honeys using fourier transform infrared microattenuated total reflectance spectroscopy

Fourier transform infrared (FTIR) spectroscopy with microattenuated total reflectance (mATR) sampling accessory and chemometrics (partial least squares and principal component regression) was used for the simultaneous determination of saccharides such as fructose, glucose, sucrose, and maltose in honey. Two calibration models were developed. The first model used a set of 42 standard mixtures of fructose, glucose, sucrose, and maltose prepared over the range of concentrations normally present in honey, whereas the second model used a set of 45 honey samples from various floral and regional sources. The developed models were validated with different data sets and verified by high-performance liquid chromatography (HPLC) measurements. The R (2) values between the FTIR-mATR predicted and HPLC results of the different sugars were between 0.971 and 0.993, demonstrating the predictive ability and accuracy of the procedure.