Accumulative effects of humic acid and multinutrient foliar fertilizers on the vegetative and reproductive attributes of citrus (Citrus reticulata cv. kinnow mandarin)

Abstract

Field trials were performed to investigate the effects of humic acid (HA) and multinutrient foliar fertilizer “Micro Power” (MP) coupled with farmer’s practices ( FP ), addressed in single and/or split dose frames at different plant phenological stages on various vegetative, reproductive, and physiological attributes of citrus trees (Citrus reticulata cv. kinnow mandarin). The results exhibited a profound response of treatments on various growth parameters (32.5% increase in plant height, 22.2% increase in fruit set branch^?1, 5.25% decrease in fruit drop percentage, 89.81% increase in fruit yield (kg), etc.) of citrus trees when compared to the control (FP). Likewise, a significant positive response was observed regarding various plant physiological parameters (leaf nutrients, total chlorophyll content, etc.) and physicochemical characteristics (ascorbic acid, total sugars, etc.) of citrus fruits. This study confirmed the reproducibility of HA and MP applications to improve the yield/quality of citrus and can lead to an organically sustainable citriculture.     

Effect of short-term supply of farmyard manure on maize growth and soil parameters in pot culture

Farmyard manure (FYM) improves various soil parameters and to a large extent, the availability of water and nutrient to crops when it is applied to the soil. This study aims to further investigate the short-term effects of different levels of FYM on maize plants and soil parameters. Maize plants grown in pot culture were treated with no FYM (control), recommended NPK (inorganic fertilizers), and FYM at 2, 4, 6, 8, and 10 t ha^?1 along with recommended NPK, and the cultures were analyzed 8 weeks after germination. Soil bulk density and soil pH decreased with the increasing levels of FYM, whereas soil porosity, soil organic matter (SOM), soil water content, plant height, root and shoot yield, and NPK uptake of maize were increased compared with the control or recommended NPK, respectively. The present results indicate that short-term application of higher FYM levels improves soil properties. Furthermore, the application of FYM at only higher rates significantly increases the nutrient uptake of maize plants due to improved soil properties. The supply of different amounts of nutrients increases biomass and nutrient uptake in plants.     

Competitive ability of some cover crop species against Asystasia gangetica and Pennisetum polystachion

Abstract

Asystasia gangetica and Pennisetum polystachion are the most troublesome weeds in oil palm plantations in Malaysia and establishment of cover crops under oil palms is an integral part of sustainable weed management in plantations. Replacement-series experiments were conducted to evaluate the mode and strength of competitiveness of four legume cover crop species, Calopogonium caeruleum, Centrosema pubescens, Mucuna bracteata and Pueraria javanica, and one soft grass species, Axonopus compressus, against Asystasia gangetica and Pennisetum polystachion. Relative yield, relative yield total and relative crowding coefficient were calculated with reference to shoot biomass. Asystasia gangetica was a consistently weaker competitor than Pennisetum polystachion. The legume cover crop species had higher relative yield when grown in mixtures, whereas the yield of Asystasia gangetica was lower in mixtures with legumes than in monoculture. The higher competitiveness of legumes was due to greater canopy height and leaf area index. Centrosema pubescens was a slightly weaker competitor than the other legumes. Although leaf area per plant of Centrosema pubescens did not differ from that of other three legumes, canopy height and blocking photosynthetically active radiation to the soil surface were lower. When grown with a cover crop for 12 weeks, dry weight per plant, leaf area and shoot number of Pennisetum polystachion increased as its proportion decreased in mixtures. Relative yield data indicated that Pennisetum polystachion is a strong competitor. Axonopus compressus was less susceptible to Pennisetum polystachion interference than the legumes. All cover crop species studied proved highly competitive against Asystasia gangetica, but none could compete against Pennisetum polystachion. The study confirms the feasibility of using a cover crop for management of Asystasia gangetica.     

Nitrate Reduction and Nutrient Accumulation in Wheat Grown in Soil Salinized with Four Different Salts

ABSTRACT

The effect of salinization of soil with Na₂SO₄, CaCl₂, MgCl₂, and NaCl (70:35:10:23) on the biochemical characteristics of three wheat (Triticum aestivum L.) cultivars (‘LU-26S,’ ‘Sarsabaz’ and ‘Pasban-90’) was investigated under natural environmental conditions. Twenty-day-old seedlings of all three cultivars were subjected to three salinity treatments: 1.3 (control), 5.0, and 10 dSm^?1 for the entire life period of plants. After 120 d of seed sowing, plant biomass production decreased by 49% and 65%, respectively, in response to 5 and 10 dSm^?1 salinity levels. Addition of salts to growth medium also had a significant adverse effect on plant height. Increasing salinity treatments caused a great reduction in nitrate reductase activity (NRA) of the leaf. The inhibitory effect of salinity on nitrate reduction rate was more pronounced at the reproductive stage than at the vegetative stage of plant growth. Wheat cultivars ‘LU-26S’ and ‘Sarsabaz’ showed less reduction in NRA due to salinity compared with ‘Pasban-90.’ Ascending salinity levels significantly reduced potassium (K⁺) and calcium (Ca²⁺) accumulation in shoots, while the concentration of sodium (Na⁺) was increased. Salts of growth medium increased the shoot nitrogen (N) concentration, whereas phosphorous (P) concentration of shoots was significantly reduced due to salinity. Wheat cultivars ‘LU-26S’ and ‘Sarsabaz’ proved to be the salt-tolerant ones, producing greater biomass, showing less reduction in NRA, maintaining low sodium (Na⁺), and accumulating more K⁺ and Ca²⁺ in response to salinity. These two cultivars also showed less reduction in shoot K⁺/Na⁺ and Ca⁺/Na⁺ ratios than in ‘Pasban-90,’ particularly at the 10 dSm^?1 salinity level.     

Changes of Physical and Chemical Characteristics during Microbial Composting of Rice Straw at Various pH Levels

ABSTRACT

The physical and chemical parameters were monitored for seven weeks during Trichoderma/Aspergillus inoculated rice straw composting at various pH levels. Three treatments (A, B, and C) were inoculated with lignocellulolytic microbial consortium (Aspergillus niger, F44 and Trichoderma viride, F26) and three were un-inoculated (D, E, and F). pH of the starting materials was amended to 5.75 (A and D), 6.75 (B and E), and 7.75 (C and F) with either acetic acid or sodium hydroxide. Three typical phases of temperature were observed both in inoculated and un-inoculated treatments during composting: mesophilic phase, thermophilic phase, and followed by cooling and maturation phase. The bioconversion were maximum in Trichoderma/Aspergillus inoculated treatments within 14–21 days as indicated by the profiles of electrical conductivity, bulk density, total carbon and nitrogen, and germination index. After day 21, the germination index of Trichoderma/Aspergillus inoculated treatment (B) without any pH amendment was increased to 74.5 indicating the maturity of compost and suitability for field application.     

In vitro regeneration and multiplication for mass propagation of Acacia ehrenbergiana Hayne: a potential reclaiment of denude arid lands

Acacia ehrenbergiana Hayne, an indigenous legume of the Middle East is an abiotic stress resistant nitrogen fixing legume which possesses valuable medicinal and economic properties. It has great potential to be used as reclaiment of denuded barren lands if only it could be propagated at a large scale. However, low seed germination and high seedling mortality apprehend its uses. Use of tissue culture technology could overcome these limitations but unfortunately there is no report describing micropropagation protocol for this species. The present study thus describes the first successful report on micropropagation of A. ehrenbergiana and also discusses the possible physiological and molecular reasons responsible to make particular culture condition, type and concentration of PGR most effective. It uses cotyledonary node explants cultured on PGR augmented Murashige and Skoog (MS) medium. A maximum of 90.3 ± 2.4 % of culture showed regeneration on benzyl adenine (BA) (10 μM) supplemented medium, maximum number of shoots (7.3 ± 0.15) were obtained on BA and NAA (0.1 μM) supplemented medium. Culture conditions were optimized by manipulation of pH of the medium, 5.8 being the best. Sub-culturing up to three passages for multiplication and thereafter induction of in vitro rooting was found to be most economical both in terms of time and money. Rizogenesis was observed best in MS medium supplemented with IBA (5.0 μM). 80 % of the rooted plants were successfully transferred to the natural condition under the sun.     

Phenotypic and genetic parameter estimates for reproductive traits in Zandi sheep

This study reports on the phenotypic and genetic (co)variance components for reproductive traits in Zandi sheep, using between 1,859 and 2,588 records obtained from 577 ewes. The data were collected from the Khojir Breeding Station of Zandi sheep in Tehran, Iran from 1994 to 2008. The basic traits were litter size at birth (LSB), litter size at weaning (LSW), litter mean weight per lamb born (LMWLB), and litter mean weight per lamb weaned (LMWLW), and the composite traits were total litter weight at birth (TLWB) and total litter weight at weaning (TLWW). Genetic analyses were carried out using the restricted maximum likelihood method that was explored by fitting the additive direct genetic effects and permanent environmental effects of the ewes as random effects and the ewe age at lambing and lambing year as fixed effects for all of the investigated traits. Akaike’s information criterion was used to choose the most appropriate model. LSB, LSW, LMWLB, LMWLW, TLWB, and TLWW direct heritability estimates were 0.07, 0.05, 0.12, 0.10, 0.08, and 0.14, respectively. The estimated fractions of variance due to the permanent environmental effects of the ewe ranged from 0.03 for LMWLB to 0.08 for LMWLW and TLWW. Corresponding repeatability estimates ranged from 0.10 for LSW to 0.22 for TLWW. Direct genetic correlations varied from ?0.61 for LSB–LMWLB to 0.88 for LSB–LSW and LSB–TLWB. Results indicate that genetic change depends not only on the heritability of traits, but also on the observed phenotypic variation; therefore, improvement of non-genetic factors should be included in the breeding programs.     

Risks factors associated with subclinical mastitis in water buffaloes in Pakistan

The present study was carried to ascertain the association of various risk factors of mastitis in water buffaloes. The milk samples from buffaloes were collected and screened through California Mastitis Test for the presence of mastitis. In the present study, 15.2 % prevalence of subclinical mastitis was recorded both at the government (13.4 %) and private farms (15.5 %). The chi-square analysis showed significantly higher involvement of the right rear and front quarters. The analysis of variance technique showed significant difference in live body weight, milk yield, teat end to floor distance (P?<?0.001), udder depth, teat length, and teat diameter in mastitic and healthy buffaloes. The frequency analysis also revealed significant difference between various groups including lactation stage, teat and/or udder pathology, teat shape, and udder shape (P?<?0.001). The logistic regression analysis revealed significant positive association of mastitis with milk leakage, live body weight, milk yield, parity, calf suckling, pendulous udder, number of attendants at the farm, dirty hind legs, and udder depth.     

Nanosilver containing grafted bamboo rayon as antibacterial material

Antibacterial textiles are gaining attention due to awareness of health and hygiene and also the requirement of protection from pathogenic bacterias. Silver nanoparticles can be best utilized for imparting such properties. As silver nanoparticles impart characteristic brown colour to substrates, material is more suitable for coloured antibacterial products. In the current study the bamboo rayon fabric was grafted with acrylamide using potassium persulfate (KPS) as an initiator and further treated with silver nitrate followed by borohydride reduction. The modified product was characterized using FTIR, TGA and SEM. The characteristic brownish tinge developed after reduction was measured spectrophotometrically. The grafted bamboo rayon with nanosilver was then evaluated for antibacterial activity against both gram positive and gram negative bacteria and durability of their antibacterial activity after washing. The product showed antibacterial activity against both types of bacterias which was found to be durable till 50 washes.     

Progression of molecular and phenotypic diversification in resynthesized Brassica juncea (L) gene pool with determinate inflorescence

Indian mustard (Brassica juncea (L) Czern & Coss) is naturally indeterminate. Plants with determinate inflorescence were first discovered in the self progenies of B. juncea (AABB; 2n = 36), resynthesized by combining A-genome from B. napus (AACC; 2n = 38) and B-genome from B. carinata (BBCC; 2n = 34). In the determinate plants, apical meristems were transformed into pods. In contrast, the inflorescence in the indeterminate plants continues to grow indefinitely while producing peripheral flowers. Genotyping and morphological characterization of newly developed determinate gene pool (A₈) showed a rapid emergence and progression of genetic and phenotypic alterations which continued even after seven generations of selfing. A large number of determinate genotypes (125) were evaluated to establish agronomic potential of determinate B. juncea. A high proportion of determinate genotypes outperformed the best indeterminate checks, suggesting that critical productivity related traits like pod number, seed size and oil content were not a function of indeterminacy. As the gene for determinacy has also been introgressed in B. napus and B. carinata, the stage is now set for future breeding to aim at crop architectural modifications through determinacy in all three types of oilseed Brassicas grown in the world. Our studies emphasized the role of polyploidy as a major force of differentiation at both genotypic and phenotypic level. Although, there was no direct correlation between evolution of genetic and phenotypic diversities following polyploidization. We suggest the use of polyploidy as a plant breeding tool to benefit from de novo variation rather than restricting its use as a method to overcome sterility following wide hybridization alone.