Combining ability for superoxide dismutase,peroxidase and catalase enzymes in cabbage head (Brassica oleracea var. capitata L.)

Antioxidant enzymes have been touted as beneficial for enhancing the fitness, preventing disorders, and mitigating the effects of aging and senescence. Our objective was to evaluate combining ability of superoxide dismutase, peroxidase, and catalase activity in cabbage head. Head samples were frozen immediately in liquid nitrogen and placed at −80 °C for assay. Less than unity values of σ²_gca/σ²_sca ratio for all three enzymes indicated predominance of non-additive gene action. The parents CMS-GA and Red Cabbage excelled as good general combiners for all antioxidants and indicated the value and need for multiple crossing. The crosses CMS-GA × Red Cabbage, CMS-GA × C-2, 83-2 × AC-204, 83-2 × EC-490174, 83-2 × AC-1021, Pride of Asia × C-4, and Pride of Asia × AC-1019 showed significant specific combining ability, which could be exploited through heterosis breeding. The hybrid combinations with high per se performance and favorable SCA estimate and involving at least one of the parents with high GCA estimate could be useful to increase the abundance of favorable alleles for enhancing the antioxidants in cabbage head.     

Comparative fatty acid profiles of wild and farmed tropical freshwater fish rohu (<Emphasis Type="Italic">Labeo rohita</Emphasis>)

The proximate composition of the whole body and the fatty acid composition of the liver, muscle, eye and brain of wild and cultured rohu (Labeo rohita) were analyzed. The cultured species was found to have significantly (P < 0.05) higher lipid contents than its wild counterpart. The saturated (SFA) and monounsaturated (MUFA) fatty acid contents were significantly higher in the cultured species, whereas the n-6 and n-3 polyunsaturated fatty acid (PUFA) levels were higher in the wild species. Fatty acids C16:0 and C18:1 n-9 were the principal fatty acids of the SFAs and MUFAs, respectively, identified in the analyses. Docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid were the predominant PUFAs in both groups, and all three were found to be present at significantly (P < 0.05) higher levels in the wild species. Erucic acid (C22:1 n-9), which was the predominant fatty acid (30.76%) in the feed, was detected only at low levels in muscle (0.30%), liver (1.04%) and eye (1.28%) of cultured fish tissue.     

Origin and cytology of a novel cytotype of Allium tuberosum Rottl. ex Spreng. (2n = 48)

Naturally occurring/spontaneously produced polyploids with six/more genomes are rarely found in Alliums. A hexaploid form of Allium tuberosum with 2n = 48 chromosomes has been isolated for the first time amongst the open-pollinated seedlings of a hypotetraploid plant (2n = 4x = 31); latter being the seed-derived product of a normal tetraploid stock (2n = 4x = 32) growing in Jammu University Botanical Garden. Except for the guard cells and pollen grains that are of increased size, this form compared to its progenitor is dwarf, has smaller leaves and bears inflorescences with few flowers. This plant is also different from its progenitor in having nearly one-fourth (27.8 %) of its pollen mother cells (PMCs) with varying chromosome number viz. 27–64, with the remaining cells having somatic or double the somatic number of chromosomes. To assess the nature of hexaploid form, its chromosomes were studied for morphological details, putative grouping and pairing properties during reduction division. Morphological similarity in the chromosomes of the present cytotype and its progenitor, arrangement of 48 chromosomes in eight groups of six chromosomes each and presence of 21.88 % euploid cells with eight hexavalents pointed towards the autopolyploid nature of the present strain. Regarding the origin of this strain, observation made on the meiosis in the two sex mother cells of the progenitor provides some clues. In the later plant, presence of most of embryo-sac mother cells with 62 chromosomes that showed 31:31 segregations and existence of majority of the PMCs with 31 chromosomes exhibiting erratic segregations indicate that the hexaploid strain has probably originated as a result of the fusion of reduced male (n = 17) and unreduced female gamete (2n = 31).     

Strategic use of Iranian bread wheat landrace accessions for genetic improvement: Core set formulation and validation

Iranian wheat landrace accessions (IWAs) were collected from country‐wide farm fields and market places in 1935 by a professor at the University of Tehran and shared with University of California at Davis, California. IWAs were further submitted to the genebank of International Maize and Wheat Improvement Center (CIMMYT), Mexico. 2,403 IWAs from CIMMYT’s genebank were assayed by DArT‐seq technology to assess genetic diversity. No apparent ecogeographic patterns related to genetic diversity were detected, probably due to long‐term transport and frequent interchange of landraces among farmers. A multivariate clustering procedure combining genotypic and phenotypic information was used in selecting a core‐set, which represented 15% of the hexaploid wheat accessions included in this study. This subset captured an estimated 93% of rare (frequency <0.05) alleles. Multisite phenotypic data (India, Mexico) validated the ability of the core‐set in detecting useful variants. Potential donor accessions for multiple traits (disease resistance, zinc concentration) were identified from the core‐set for wheat‐breeding. This report illustrates a breeder friendly robust core‐set formulation strategy for harnessing the useful genetic variation stored in the genebanks.     

PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES RESULTING FROM CADMIUM AND ZINC ACCUMULATION IN CARROT PLANTS

The interactive effect of cadmium (Cd) and zinc (Zn) bioaccumulation on physiological and biochemical characteristics of carrot (Daucus carota L. var Pusa Kesar) plants grown with different levels of Cd and Zn was examined. The combined application of Cd and Zn (Cd+Zn) had synergistic and antagonistic effects at low and high concentrations, respectively, on Cd accumulations in plants, chlorophyll b, and photosynthesis and transpiration rates. Whereas both low and high Cd+Zn concentrations had synergistic effects on Zn accumulation, ascorbic acid, protein content, total phenols, peroxidase activity, chlorophyll a, total, carotenoids and stomatal conductance. Bioaccumulation of Cd had strong and negative relationships with measured physiological and biochemical parameters. The study further showed that Cd and Zn in combination have more toxic effects on carrot plants as compared to their individual treatments. This study concludes that interactive effects of Cd and Zn on test plant depend on their ratios present in plants.     

RHIZOSPHERIC EFFECT OF VESICULAR ARBUSCULAR MYCORRHIZAL INOCULATION ON BIOMASS PRODUCTION OF RUTA GRAVEOLENS L.: A POTENTIAL MEDICINAL AND AROMATIC HERB

A bio-inoculation experiment was performed on Ruta graveolens L., known as “Garden Rue” seedlings for the biomass production. Seedlings were inoculated with single and in combined mycorrhizal treatments. All inoculated seedlings showed significant biomass production than control seedlings. The phosphorus (P) content was more in seedlings inoculated with consortium of three native VAM fungi followed by Glomus mosseae, Acaulospora laevis and Gigaspora gigantea alone treatments. The control seedlings had the least P content but root P content was more than shoot P content in all treatments. The biomass of shoot and root was also significantly more in seedlings inoculated with consortium followed by G. mosseae, A. laevis and G. gigantea alone treatment. The control seedlings again had low shoot and root biomass. The Biovolume index (B_i) was also high in all inoculated treatments than non-inoculated control but consortium treatment (7.98) had at par B_i than rest of inoculation treatments. The quality index (Q_i) value was also high in mixed consortium (1.42) and A. laevis treatment (1.42) each respectively than G. mosseae (1.38) and G. gigantea (1.29) treatments. Control seedlings had low value of Q_i (1.27). The present study indicates that G. mosseae, A. laevis, G. gigantea are the best strains of VAM symbionts when mixed together for inoculating the R. graveolens to get higher yield of biomass. A. laevis is also good strain of VAM fungi for the same purpose. The G. gigantea alone proved least effective strain for inoculation purpose in R. graveolens but when mixed together in consortium of native VAM fungi as described above executed good results for enhancing the biomass production.     

EFFECT OF PACLOBUTRAZOL AND PUTRESCINE ON ANTIOXIDANT ENZYMES ACTIVITY AND NUTRIENTS CONTENT IN SALT TOLERANT CITRUS ROOTSTOCK SOUR ORANGE UNDER SODIUM CHLORIDE STRESS

The effects of paclobutrazol (PBZ) and putrescine (Put) on antioxidant enzymes activity, proline contents and nutrients uptake were studied on salt tolerant citrus rootstock sour orange. Six-month-old nucellar seedlings grown in pots and subjected to three levels of PBZ and two levels each of salinity and Put for 90 days. Seedlings treated with PBZ or Put alone or in combination had higher anti-oxidant enzymes activities, accumulation of proline and nutrients contents like potassium (K⁺) and calcium (Ca²⁺) under both saline and non-saline conditions. Further, application of PBZ or Put alone or in combination also reduced the accumulation of both Na⁺ and Cl^? ions in leaves and roots in NaCl stressed seedlings. A combined application of 250 mg L^?1 PBZ and 50 mg L^?1 Put proved to be more effective in improving proline and Ca²⁺ content and restricting accumulation of Na⁺ ions in leaf tissues.     

SOIL POTASSIUM FRACTIONS IN RICE-WHEAT CROPPING SYSTEM AFTER TWELVE YEARS OF LANTANA RESIDUE INCORPORATION IN A NORTHWEST HIMALAYAN ACID ALFISOL

A long-term field experiment with rice-wheat cropping was started in the wet season of 1988 with four levels of lantana (Lantana camara L.) (0, 10, 20, and 30 Mg ha^?1 on fresh weight basis) and three tillage practices (No puddling, puddling, and soil compaction). From wet season of 1997, however, three tillage practices were replaced with three levels of nitrogen (N) and potassium (K) to rice (33, 66, and 100% of recommended) and 66% of recommended N, phosphorus (P), and K to wheat. Phosphorus was totally omitted for the rice crop. The recommended N and K for rice was 90 and 40 kg ha^?1, whereas the recommendations for N, P, and K for wheat were 120, 90 and 30 kg ha^?1. Organic amendments are known to improve soil productivity under rice-wheat cropping by improving physical conditions and nutrient status of the soil, but their availability is restricted. There is a need to identify locally available and cost-effective organic materials that have minimal alternate uses as fodder and fuel. We evaluated Lantana camara L. residues, a fast-growing weed in nearby wastelands, as a potential soil organic amendment. Among the different fractions of K, nonexchangeable K was dominant followed by exchangeable and water soluble K. The incorporation of lantana (10 to 30 Mg ha^?1) over the last 12 years has resulted in a significant build-up of all the K fractions, the maximum being in water-soluble K (10 to 32%) followed by exchangeable K (18 to 27%) and least in nonexchangeable K (5 to 7%) over no lantana incorporation. The increasing levels of these two inputs significantly and consistently increased ammonium acetate (NH₄OAc)- extracted K (available K) content in soil and also resulted in significantly higher accumulation of K by the crops during the years of experimentation. Among different K fractions, exchangeable K was observed to be the most important K fraction contributing towards wheat and rice yields as well as K accumulation by wheat and rice. Stepwise multiple regression equations indicated that exchangeable K was the most important variable contributing towards total variation in grain yield and K accumulation by wheat or rice.     

ENHANCEMENT OF PEA PRODUCTION USING LEAF EXTRACT OF WITHANIA SOMNIFERA L. UNDER SUB-TROPICAL FIELD CONDITIONS OF KULLU,NORTHWESTERN HIMALAYA,INDIA

The present study investigates the promoting effects of leaf extract of Withania somnifera L plant on growth, biomass, and yield of Pisum sativum L plants. The growth and biomass of pea plants increased significantly over control due to leaf extract (LE-WS) treatment. Pea plants treated with LE-WS and ascorbic acid (L-AA) showed higher number as well as total dry weight of nodules over the control. The economic yield of pea plants due to LE-WS and L-AA treatments increased by 84 and 114%, respectively over control. The economic yield was significantly correlated with number of nodules (R² = 0.75, P <0.001). The study suggests that LE-WS may be used to promote the growth and increase the production of pea plants in areas having multiple stresses. Detailed study on the use of extracts of medicinal plants as a tool to reduce the adverse effects of single stress is further required.     

Effects of shade regimes and planting geometry on growth,yield and quality of the natural sweetener plant stevia (Stevia rebaudiana Bertoni) in north-western Himalaya

During 2008 and 2009, field experiments were conducted at the research farm of CSIR-Institute of Himalayan Bioresource Technology, Palampur, India to assess the effect of shade levels (no shade, 25% shade, 50% shade, 75% shade) and plant geometry levels [30 × 15 cm (north–south, N–S), 45 × 10 cm (N–S), 30 × 15 cm (east–west, E–W) and 45 × 10 cm (E–W)] on the growth, yield and quality of stevia. Plant development was fastest in controls and slowest in stevia plants growing at minimum light (75% shade). These plants showed delayed bud formation and flowering. Significantly, higher dry leaf yield was recorded when the crop was grown under 25% shading than under 50 and 75% shade. Total steviol glycosides content decreased with increasing shade levels. All shade levels resulted in the same leaf-to-stem ratio, which was significantly higher than that obtained under ambient light. Plant geometry significantly affected the number of leaves and leaf dry weight plant^–1. During both years, dry leaf weight was highest in the wider row spacing (45 × 10 cm) than in the narrow row spacing (30 × 15 cm). Stevia spaced at 30 × 15 cm in an E–W direction recorded significantly higher total steviol glycosides at 2 months after transplanting (MAT).