Growth and Physiological Changes in Bitter-Gourd Plants Grown with Variable Calcium Supply in Sand Culture

Bitter-gourd (Momordica charantia L.) cv. ‘Jhallari’ plants were grown in refined sand at graded levels of calcium (Ca) supply ranging from acute deficiency (0.02 mM) to excess (8 mM). Apart from the production of characteristic visible symptoms of the respective stresses, deficient (< 4 mM) or excess (8mM) supply of Ca restricted plant biomass and fruit yield. In leaves, the concentration of chlorophyll, Hill reaction activity and the activities of catalase, peroxidase, acid invertase, ATPase, and α-amylase were reduced, but the activity of acid phosphatase was increased by deficiency of Ca. Excess Ca (8 mM) supply significantly reduced the concentration of chlorophyll, Hill reaction activity and the activity of catalase and increased the specific activities of peroxidase, acid invertase, ATPase, α -amylase, and acid phosphatase. Tissue concentration of Ca in leaves and fruits increased with increase in Ca supply from 0.02 to 8 mM. Tissue concentrations in young leaves representing the thresholds of deficiency or toxicity of Ca are found to be 1.12 and 1.98%, respectively. The critical tissue concentration in these leaves suggestive of severe deficiency of Ca is 0.85%.     

Enhanced growth of micropropagated bulblets of Lilium sp. inoculated with arbuscular mycorrhizal fungi at different P fertility levels in an alfisol

Summary

The effect of three arbuscular mycorrhizal (AM) inocula at four available levels of phosphorus (8.41, 12.53, 13.63 and 14.6 ppm) in non-disinfected soil was studied on the growth, flowering, P uptake and root colonization in micropropagated bulblets of Lilium sp. (Asiatic hybrid ‘Gran Paradiso’). The inoculated bulblets fared significantly better than the uninoculated ones in terms of all the growth variables, namely size, weight, shoot length, number of leaves and leaf area, and in P uptake. However, bulblets inoculated with different AM inocula had optimum growth at different P levels. Bulblets inoculated with indigenous mixed vesicular-arbuscular mycorrhiza species (VAM I) and Glomus intraradices isolate 2 (VAM III) showed the best growth and early flowering at available soil P of 13.6 ppm, whereas those inoculated with Glomus intraradices isolate 1 (VAM II) showed higher growth at 2.5 ppm available soil P. Amongst the three tested inocula, VAM I promoted maximum shoot length, bulblet size, and weight at 13.6 ppm P. The bulblets under this treatment also flowered earlier, nearly a month before the uninoculated control ones.     

Soil Boron Fractions and Response of Green Gram in Calcareous Soils

A greenhouse experiment with green gram on boron (B) deficient calcareous soils was conducted for two years at Ludhiana (Punjab), India to study soil B fractions and response of green gram to B application. Three soils with calcium carbonate (CaCO₃) content 0.8 (Soil I), 2.1 (Soil II) and 4.6 (Soil III) percent were collected from different sites of Ludhiana and Bhatinda districts, Punjab, India. The treatments comprised of five levels of soil applied B (0, 0.5, 0.75, 1.0, and 1.5 mg B kg^?1). The experiment was laid out in completely randomized design (CRD) factorial design with three replications. Readily soluble B comprised 0.39 to 0.76 percent in Soil I, 0.32 to 0.54 percent in Soil II, and 0.21 to 0.34 percent in Soil III of the total B, taking into account of all the levels of B applied at both stages of crop growth. Readily soluble B increased with increasing application rates of B and decreased from grand growth stage (40 days after sowing) to maturity of the crop. Specifically adsorbed, oxide bound, residual, and total B was higher in Soil III as compared to Soil II or Soil I. At maturity, specifically adsorbed B converted into other fractions to maintain equilibrium in soil solution. Organically bound B was greater than oxide bound B. Among all fractions, the residual fraction accounted for the major fraction of the total B. Soil application of lowest level of B was adequate to cause significant increase in dry matter yield and seed yield of green gram regardless of type of soil.     

Biomedical Compounds from Marine organisms

The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.     

EST-SSR based estimates on functional genetic variation in a barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) collection from Egypt

Genetic diversity was investigated in a set of 27 barley genotypes, originated from Egypt, using 23 expressed sequence tag (EST)-derived simple sequence repeats (eSSRs), representatives of the seven barley chromosomes. Ninety-five alleles were detected among all the barley accessions. For 22 polymorphic eSSRs, the number of alleles per locus varied from 2 to 12, with a mean of 4.318 alleles per locus. The lowest and the largest number of alleles per locus among the seven homeologous groups was observed in homeologous group 5H and 4H with 3.00 and 6.33, respectively. The gene diversity increased as the number of alleles increased. Gene diversity for 22 ESTs loci varied from 0.137 for GBM1404 to 0.896 for GBM1015 with an average of 0.563. A significant correlation coefficient between gene diversity and the number of alleles was high, r = 0.741 (P < 0.01). Cluster analysis was conducted based on eSSRs data to group the barley genotypes and to construct a dendrogram. Four groups can be distinguished by truncating the dendrogram at gs value of 0.77.     

Patterns of spatiotemporal change in large mammal distribution and abundance in the southern Western Ghats, India

Large mammals face high risks of anthropogenic extinction owing to their larger body mass and associated life history traits. Recent worldwide mammal declines have highlighted the conservation importance of effective assessments of trends in distribution and abundance of species. Yet reliable data depicting the nature and extent of changes in population parameters is sparse, primarily due to logistical problems in covering large areas and difficulties in obtaining reliable information at large spatial scales, particularly over time. We used key informant surveys to generate detection histories for 18 species of large mammals (body mass > 2 kg) at two points in time (present and 30 years ago) in the Southern subregion of the Western Ghats global biodiversity hotspot. Multiple-season occupancy models were used to assess temporal trends in occupancy, detectability and vital rates of extinction and colonization for each species. Our results show significant declines in distribution for large carnivores, the Asian elephant and endemic ungulates and primates. There is a significant decline in detectability for 16 species, which suggests a decline in their abundance. These patterns of change in distribution and abundance repeat in our assessments of spatial variation in occupancy dynamics between the three contiguous forest complexes and two human-dominated landscapes into which the southern Western Ghats has been fragmented. Extinction rates are highest in the human-dominated landscapes. Declines in abundance for several species suggest the presence of extinction debts, which may soon be repaid with imminent range contractions and subsequent species extinctions unless immediate remedial conservation measures are taken. Detection/non-detection surveys of key informants used in an occupancy modeling framework provide potential for rapid conservation status assessments of multiple species across large spatial scales over time.     

Inheritance of siliqua characters in Indian colza I. Locule number and siliqua position

Summary F₁, F₂, BC₁ and BC₂ generations, involving bilocular and tetralocular siliquae and with upright and pendent siliqua position, were studied with their parents. The segregation pattern in these generations indicated that number of locules is monogenically governed with the allel for bilocular type (VV-two valved pods) showing complete dominance over tetralocular (vv). Upright siliqua position is governed by two dominant genes (Up₁ Up₁ Up₂ Up₂) and pendent by two recessive genes (up₁ up₁ up₂ up₂). However, in absence of even a single dominant gene it give rise to a third type of siliqua position i.e. parallel.     

STMS markers for grain protein content and their validation using near-isogenic lines in bread wheat

The present study, undertaken as a continuation of an earlier study on quantitative trait loci (QTL) analysis of grain protein content (GPC) in bread wheat (Prasad et al. 1999), includes the following: (1) identification of an additional molecular marker associated with GPC; (2) development of near‐isogenic lines (NILs) for high GPC; and (3) the use of three sets of NILs (a total of 10 NILs) to validate the two available markers linked with QTL for GPC. A total of 114 sequence‐tagged microsatellite site (STMS) primer pairs (that were not used in the previous study) were used for detection of polymorphism between the two parents (PH132, with high GPC; WL711, with low GPC) of a mapping population of 100 recombinant inbred lines (RILs). A total of 95 primer pairs gave amplification products, of which only 30 detected reproducible polymorphism between the parental genotypes. Bulked segregant analysis was conducted using these 30 primers on two bulks (each comprising eight RILs) representing the two extremes of the normal distribution. A solitary primer pair (WMC415) showed association with GPC, which was further confirmed through selective genotyping. Subsequently, 100 RILs were genotyped. A single‐marker linear regression analysis showed significant association between the marker WMC415 and GPC, thus identifying a quantitative trait locus (designated as QGpcccsu‐5A1), which explained 6.21% of the variation for GPC among the RILs. The above STMS marker, together with the STMS marker (WMC41) identified earlier, explains approximately 25% of the variation for GPC. In order to conduct validation of the above two available markers, 10 NILs were developed for high GPC using two genotypes (WL711 and HD2329) with low GPC as recipient parents and another two genotypes (PH132 and PH133) with high GPC as donor parents. NIL 2233 (with 11.7% GPC), derived from HD2329, when tried with WMC41 gave a characteristic amplification profile similar to that of its donor parent PH132, and NIL 2215 (with 11.9% GPC) derived from WL711, when tried with WMC415 gave an amplification profile that resembled its donor parent PH133. The remaining eight NILs with high GPC gave patterns similar to those of their corresponding recipient parents with both the markers, suggesting that either the QTL, other than those associated with the above markers, were actually transferred from the donor parents and contributed to high GPC in these NILs or that recombination had occurred between the markers identified and the corresponding QTL. Thus, the marker validation conducted using NILs, while demonstrating the utility of these two microsatellite markers for use in marker‐assisted selection in plant breeding, also suggested that many more QTL exist that would need to be identified using closely linked molecular markers.