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1.
In 2013, we re-inventoried all lianas(C1 cm diameter measured at 1.3 m from the rooting point) in four1-ha permanent plots distributed one each in four sites of inland tropical dry evergreen forest on the Coromandel Coast(Pudukottai district) of peninsular India, established in 2003. Among the four sites, Shanmuganathapuram(SP)and Araiyapatti(AP) were much disturbed and the other two sites(Karisakkadu—KR and Maramadakki—MM)were moderately disturbed. We inventoried a total of 3425 lianas representing 37 species of 33 genera and 22 families.Over a decade(2003–2013) liana species richness increased at two sites(MM and SP) and no changes occurred at the other two sites. Liana abundance increased by 210, 211, 164 and 162 individuals at sites AP, KR, MM and SP, respectively, and basal area increased(from 1.09 to1.76 m2 at AP, 0.67 to 0.86 m2 at KR, 1.68 to 2.06 m2 at MM, and from 0.44 to 1.06 m2 at SP). Over a 10-year period, three species(Abrus precatorius, Canavalia virosa,and Cocculus hirsutus) were lost and five species(Gloriosa superba, Ampelocissus tomentosa, Capparis sepiaria,Aganosma cymosa and Tiliacora acuminata) were newly added. Total aboveground biomass increased by 18.5, 0.74,3.6 and 9.5 Mg ha-1, respectively, at sites AP, KR, MM and SP.  相似文献   
2.
Randomly amplified polymorphic DNA (RAPD) fingerprinting approach was applied to assess genetic diversity in different accessions of rejuvenating and intellect-promoting ancient ayurvedic medicinal herb Bacopa monnieri (L.) Pennell collected from four Southern Indian states, along with in vitro micropropagated samples maintained in the laboratory for 5 years. With the 10 analyzed primers, 110 distinct bands, in the size range of 250–870 bp were observed, and among which 14 (12.72%) were polymorphic. Among the random primers used, only OPD 02 generated highest percentage of polymorphism with 30.77. Whereas OPD 08 generated a maximum of 18 amplified bands, but with only 1% polymorphism. Cluster analysis done on the basis of similarity co-efficient generated from RAPD profiles indicated all the accessions were divided into two sub-groups based on genetic distances under one major cluster. Major cluster is only the lone loose group of the Bm.2 collected from Kerala (KER) and in vitro micropropagated plant (IVMP) maintained in the lab. The other sub-group consisted of Bm.1 and Bm.3 collected from Tamil Nadu (TN) and Andhra Pradesh (AP) respectively, which are genetically similar and showed similarity with accessions from Karnataka Bm.4 (KK). These two sub-groups were joined together at 0.66 genetic distance level. Overall, the levels of genetic similarity within the accessions varied from 0.24 to 0.80, the matrix ranged from 0.36 to 0.80, with a mean value of 0.68 indicating genetic similarity at low level.  相似文献   
3.
Total phenolics, ascorbic acid, and betalain contents of differently colored cactus pear clones (nine Opuntia ficus-indica [L.] Mill. clones and one O. robusta Wendl. clone) were investigated and related to their respective antioxidant potential assessed by Trolox-equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays. TEAC and ORAC values were very highly correlated with each other and also with values for total phenolics, betalain contents, and ascorbic acid concentrations. Total phenolics had the greatest contribution to ORAC and TEAC values. High-performance liquid chromatography (HPLC)-diode array detector (DAD)-tandem mass spectrometry (MS/MS) measurements of cactus pear juices permitted the differentiation of the clones based on variations in pigment patterns and betalain concentrations. The red and yellow betalains were absent in lime green colored cactus fruits. The ratio and concentration of these pigments were responsible for the yellow, orange, red, and purple colors in the other clones. Progeny of purple and lime green colored parents were characterized by 12% and 88% of plants bearing lime green and purple fruit, respectively. This implies that the genes for betalain production were lacking in the lime green fruits but could be provided by a parent with a complete set of genes, that is, purple fruits. Besides known pigments typical of Cactaceae, two unexpected betalains were identified. Whereas gomphrenin I was found for the first time in tissues of cactus plants, methionine-betaxanthin has never been described before as a genuine betalain. In addition to their alleged health-promoting properties, various combinations of yellow betaxanthins and red-purple betacyanins may allow the development of new food products without using artificial colorants.  相似文献   
4.
In an outdoor culture of Tubifex tubifex, occurrence of the larvae of Chironomus pulcher and C. calligaster was recorded. An increase in the density of Chironomus larvae reduced the standing biomass of tubifex and made the harvest impossible.  相似文献   
5.
Midgut juice of Plutellaxylostella strain PXR which is resistant to Cry1Ac was biochemically characterized relative to the susceptible PXS strain. The midgut juice of PXR (PXR-Juice) was shown to process Cry1Ac protoxin to 60 kDa active toxin with the same processing pattern as that of juice from PXS (PXS-Juice) in SDS–PAGE. PXS larvae which were given the Cry1Ac toxin pre-processed with PXR-Juice were killed with the same rate as that with Cry1Ac pre-activated by trypsin. PXR-Juice was found to contain three times larger amount of 66 kDa protein (P66) than PXS-Juice and the N-terminal amino acid sequence of P66 was matched to that of glucosinolate sulfatase in data base search. The protein band of P66 was coincided with the band of p-nitro phenyl sulfatase activity in zymogram. P66 purified to homogeneity in SDS-PAGE bound to Cry1Ac and soybean agglutinin, and KD for Cry1Ac was estimated to be 718 nM with surface plasmon resonance analysis. Using purified sulfatase, Km and Vmax were estimated and involvement of the enzyme in the PXR resistance was discussed.  相似文献   
6.
Abstract

In recent decades, chemical fertilizers create a thread to organic agriculture and food security. To overcome this issue, the present study aimed to investigate the influence of liquid seaweed extracts (LSEs) prepared from Padina boergesenii (PB) and Gracilaria edulis (GE) on growth, development, biochemical characteristics and yield traits of foxtail millet. The various concentrations of individual (20, 40, 60, and 80%; v/v) and combined (10?+?10, 20?+?20, 30?+?30, and 40?+?40%; v/v) PB and GE LSEs were supplied through foliar spray method. The results imply that germination bioassays, vegetative plant growth were significantly increased in lower concentration of LSEs. Further, exposure of foxtail plants to combined foliar spray application of (20?+?20%; v/v) LSEs enriched photosynthetic pigments, total soluble sugar and total soluble protein, compared with single LSEs and control foliar spray methods. Additionally, LSEs enhanced the yield attributes such as the average number of seeds (971.5/panicle) and mean length of panicle (18.4?cm) in PB?+?GE LSEs (20?+?20%; v/v) treatment. This is the first report, to assess the synergistic biostimulant ability of PB and GE LSEs in plant growth, quality improvement and yield attributes of foxtail millet. In conclusion, this present study suggests that combination of PB?+?GE LSEs foliar spray application could serve as an ideal biostimulant and a potential alternate to hazards chemical fertilizer in the green agriculture.  相似文献   
7.
The aim of this study was to evaluate the effect of biochar and organic soil amendments on soil physicochemical and microbial load, carbon sequestration potential, nutrient uptake and yield of groundnut in acidic red soil under rainfed condition. Biochar was prepared from red gram, cotton, maize stalk and mesquite wood using pilot scale slow pyrolysis biochar unit. The above sources of biochar at the rate of 2.5 and 5 t ha?1 and enriched farmyard manure 0.75 t ha?1, composted coir pith 10 t ha?1 and arbuscular mycorrhizae 100 kg ha?1 were applied as basal with required nitrogen, phosphorous and potassium fertilizer. Biochar amendment at the rate of 5 t ha?1 reduced the bulk density from 1.41 to 1.36 g cm?3 and increased the soil moisture 2.5%. With respect to soil chemical changes, it raised soil pH from 5.7 to 6.3; increased the cation exchange capacity 1.4 cmolkg?1 and enhanced the carbon buildup 4.4 t ha?1. The significant differences in bacteria, fungi and actinomycetes population were observed between biochar and control. The nitrogen, phosphorous and potassium were better utilized under biochar and composted coir pith, which was 21, 5 and 20 kg ha?1 higher than control. The experimental results suggested that application of biochar to acidic red soil favoured good soil physical, chemical and biological environment, and these positive changes influenced growth and yield attributes and enhanced pod yield 29% over control.  相似文献   
8.
Tribulus terrestris L. (Zygophyllaceae) is one of the highly traded raw drugs and also used as a stimulative food additive in Europe and USA. While, Ayurvedic Pharmacopoeia of India recognizes T. terrestris as Goksura, Tribulus lanuginosus and T. subramanyamii are also traded by the same name raising issues of quality control. The nuclear ribosomal RNA genes and ITS (internal transcribed spacer) sequence were used to develop species-specific DNA markers. The species-specific markers efficiently amplified 295 bp for T. terrestris (TT1F and TT1R), 300 bp for T. lanuginosus (TL1F and TL1R) and 214 bp for T. subramanyamii (TS1F and TS1R). These DNA markers can be used to distinguish T. terrestris from its adulterants.  相似文献   
9.
Vidalia onion varieties Nirvana, DPS 1032, Yellow 2025, King-Midas, and SBO 133 grown at Vidalia, Georgia, were analyzed for flavonoid content. A high-performance liquid chromatographic (HPLC) method with photodiode array detection was used for quantification. Compounds were analyzed as aglycons after acid hydrolysis with 1.2 M HCl. Identification of each compound was based on comparison of its retention time and UV spectra with those of pure commercial standards. Three major flavonoids, kaempferol, myricetin, and quercetin, were identified and quantified. Quercetin was the major flavonoid (7.70-46.32 mg/100 g fresh weight, FW) present in all varieties, followed by myricetin (2.77-4.13 mg/100 g FW). Minor quantities of kaempferol (1.10-1.98 mg/100 g FW) were also detected. The total polyphenols and Trolox equivalent antioxidant capacity (TEAC) ranged from 73.33 to 180.84 mg/100 g FW and 0.92-1.56 microM TEAC/g FW, respectively. A positive but weaker correlation was obtained for total polyphenols versus antioxidant capacity. Nevertheless, a stronger correlation (r(2) = 0.34) was obtained between flavonoid content versus antioxidant capacity. The data indicate that Vidalia onions are a rich source of quercetin, and they also contain myricetin and kaempferol.  相似文献   
10.
The objective of this experiment was to assess the features and extent of follicular apoptosis in the water buffalo (Bubalus bubalis) ovary using classical histology and nick end labelling technique. Ovaries (n = 40) procured from the slaughterhouse were used for the study. The sections (5 μm) were used for detection of terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick end labelling (TUNEL) and classical histology (H&E). Those follicles showing ≥ 5% TUNEL positivity (TUNEL assay) and pyknotic nuclei (histology) in granulosa cells were classified as atretic. Based on histology, the atretic primary and secondary follicles (%) were 93.82 and 95.62 respectively. The histology study reveals that the rates (%) of atresia in <1, 1–3, 3–5 mm and >5 mm were 36.90, 40.50, 62.84 and 74.5 respectively. Further the atretic tertiary follicles (%) were significantly lower than the primary and secondary classes of follicles. TUNEL assay reveals that the atretic rate (%) of tertiary follicles in <1, 1–3, 3–5 and ≥ 5 mm class follicles were 50.88, 53.84, 81.81 and 36.36 respectively. The percentage of atresia in >5 mm diameter follicles were significantly lower in TUNEL than histology. Percentages of granulosa and thecal cells positive for atresia by TUNEL were 30.7 ± 0.53 and 13.82 ± 0.18 respectively per follicle. The initial structural changes in atretic follicles were seen primarily in the granulosa cells. In severely atretic follicles TUNEL positive granulosa cells along with theca cells have to be considered in assessing the rate and extent of atresia.  相似文献   
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