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91.
Mono-cropping is the most common farming practice followed in the North Eastern Hilly Region (NEHR) of India and farmers leave the land fallow after harvesting the main crop. The identification of suitable sequential crops is essential to increase the cropping intensity, land-use efficiency and overall productivity of the land. Therefore, a study was carried out during 2008–09, 2009–10 and 2010–11 on maize (rainy season) followed by table pea, mustard, French bean and groundnut (post rainy season). Sequence crops were imposed with paddy straw mulch at 5.0 t ha?1 and without mulch. The availability of water and moisture retention was higher (p < 0.05) on mulched plots, yield was also higher. However, recorded soil temperature was higher on mulched plots at 08.00 hours and lower at 12.00 and 16.00 hours compared with the no-mulch plots. Recorded maize equivalent yield, production efficiency, economics and total energy use and output (MJ ha?1) were higher for maize–French bean.  相似文献   
92.
The Non-Structural protein 1 of Canine Parvovirus-2 (CPV2.NS1) plays a major role in viral cytotoxicity and pathogenicity. CPV2.NS1 has been proven to cause apoptosis in HeLa cells in vitro in our laboratory. Here we report that CPV2.NS1 has no toxic side effects on healthy cells but regresses skin tumors in Wistar rats. Histopathological examination of tumor tissue from CPV2.NS1 treated group revealed infiltration of mononuclear and polymorphonuclear cells with increased extra cellular matrix, indicating signs of regression. Tumor regression was also evidenced by significant decrease in mitotic index, AgNOR count and PCNA index, and increase in TUNEL positive apoptotic cells in CPV2.NS1 treated group. Further, CPV2.NS1 induced anti-tumor immune response through significant increase in CD8+ and NK cell population in CPV2.NS1 treated group. These findings suggest that CPV2.NS1 can be a possible therapeutic candidate as an alternative to chemotherapy for the treatment of cancer.  相似文献   
93.
94.
Host plant resistance is an important component for management of the melon fruit fly, Bactrocera cucurbitae (Coquillett), owing to difficulties associated with its chemical and biological control. Various biochemical traits including total sugar, reducing sugar, non-reducing sugar, tannins, phenols, alkaloids, flavinoid and pH contents of fruit were studied on 11varieties/ genotypes of muskmelon, Cucumis melo L., in relation to resistance against B. cucurbitae under field conditions. Significant differences were found in tested varieties/ genotypes for fruit infestation and larval density per fruit. AHMM/BR-1, RM-50 and AHMM/BR-8 were the most resistant; MHY-5, Durgapura Madhu and Pusa Sarabati were moderately resistant; AHMM/BR-13, Pusa Madhuras and Arka Jeet were susceptible; whereas Arka Rajhans and GMM-3 were the highly susceptible varieties/ genotypes to fruit fly in both seasons, 2011 and 2012. The larval density per fruit increased with an increase in percent fruit infestation and there was a significant positive correlation (r = 0.97) between percent fruit infestation and larval density per fruit. Total sugar, reducing sugar, non-reducing sugar and pH were lowest in resistant and highest in susceptible varieties/ genotypes, whereas tannins, phenols, alkaloids and flavinoid contents were highest in resistant and lowest in susceptible varieties/ genotypes. Total alkaloid and pH contents explained 97.96% of the total variation in fruit fly infestation and 92.83% of the total variation in larval density per fruit due to alkaloids and total sugar contents.  相似文献   
95.
We have examined the genes of the endothelin system that are targets for regulation by prostaglandin F2alpha (PGF2alpha). The effects of a luteolytic dose of PGF2alpha ) on the mRNA encoding endothelin converting enzyme-1 (ECE-1), pre-pro endothelin-1 (pp ET-1) and the ET receptors ETA, ETB, in bovine corpus luteum (CL) during the early (days 1 and 4), mid (day 10) or late (day 17) luteal phases were examined. The effect of the PGF(2alpha) treatment on ECE-1 protein, Big ET-1 and the biologically active mature ET-1 peptide were also examined. Most importantly, the direct ECE-1 activity was determined. Before day 10 of the cycle, in a PGF2alpha-independent manner, the amounts of mRNA encoding ET-1, ECE-1, ETA, and ETB were increased steadily from day 1. After day 10 of the cycle, expression of mRNA encoding pp ET-1 and ETA acquired responsiveness to exogenous PGF2alpha and both genes were up-regulated by the PGF2alpha treatment. This effect of PGF2alpha was also detected for the proteins corresponding to the mature ET-1. The enzymatic activity of ECE-1 remained unchanged throughout the lifespan of the CL in spite of the detected changes in mRNA and protein. The results suggest that the luteal endothelin system is regulated in a PGF2alpha-independent and -dependent manner. Importantly, an alteration in luteal ET-1 availability is most likely achieved by modulating the expression of mRNA encoding pp ET-1 and not by the amount or activity of ECE-1. This interpretation is supported by the observation that the activity of ECE-1 remained unchanged throughout the ovarian cycle. The combined effects of greater ET-1 availability and gene expression encoding the ETA receptor in the late luteal phase could render the CL, at this developmental stage, more sensitive or responsive to ET-1. If the luteal tissue is responsive to the available ET-1 during the early phase of the ovarian cycle, an additional role for ET-1 should be considered beyond mediating the luteolytic actions of PGF2alpha. Agents blocking the actions of ET-1 might be the best approach to interfere with the luteal ET system and test its physiological role(s) in vivo.  相似文献   
96.
This study was designed to investigate the sensitivity and specificity of three methods for detecting the onset of cyclicity in post-partum Murrah buffaloes. The methods investigated were visual signs, transrectal ultrasonography, and serum progesterone (P4) assay. For this study, 102 post-partum Murrah buffalo cows were grouped for monitoring their ovarian activity. The first group of buffaloes was between 26 and 35 days post-partum. Thereafter, the buffalo cows that calved were grouped after every 10 days for the study sample. Thus, the study animals were adjudged between 26 and 35, 36–45, 46–55, 56–65, 66–75, 76–85, and 86–95 days post-partum with an average of 30, 40, 50, 60, 70, 80, and 90 days post-partum, respectively. Visual estrus signs were monitored twice daily, and simultaneously, ultrasound examination was carried out at 10 days interval for accessing the presence of corpus luteum (CL). Serum P4 was estimated in the animals which were adjudged cyclic by ultrasound examination, and the assay was repeated after 10 days. The buffalo cows in estrus were inseminated artificially, and pregnancy status was assessed after 30 days post-insemination. In this study, the sensitivity and specificity of visual observation were low (39.37 and 70.73%, respectively) when compared to P4 assay (98.80 and 96.47%) and ultrasound examination (single, 97.59 and 97.59%; double, 100 and 100%), respectively. Furthermore, the sensitivity and specificity of single and double ultrasound examination and P4 assay were comparable. In conclusion, this study reports that single and double ultrasound examination and P4 assay are more efficient than visual observation in detecting the onset of ovarian cyclicity in post-partum Murrah buffaloes.  相似文献   
97.
Background: An oviduct-specific glycoprotein, OVGP1, is synthesized and secreted by non-ciliated epithelial cells of the mammalian oviduct which provides an essential milieu for reproductive functions. The present study reports the effects of recombinant buffalo OVGP1 that lacks post-translational modifications, and native Buffalo OVGP1 isolated from oviductal tissue, on frozen-thawed sperm functions and in vitro embryo development.Results: The proportion of viable sperms was greater(P 0.05) in the recombinant OVGP1-treated group compared to the native OVGP1-treated group at 2 h, 3 h, and 4 h of incubation. The proportion of motile sperms at3 h and 4 h of incubation; and membrane-intact sperms at 4 h was greater(P 0.05) in the native OVGP1-treated group compared to the control and recombinant OVGP1-treated groups. The proportion of capacitated and acrosome-reacted sperms was greater(P 0.05) in the native OVGP1-treated group compared to the recombinant OVGP1 group at 4 h. The rates of cleavage of embryos and their development to the blastocyst stage were greater(P 0.05) in the presence of either native or recombinant OVGP1 in comparison to control at 10 μg/mL concentration as compared to 5 or 20 μg/mL.Conclusions: The study suggests that both native and recombinant OVGP1 impart a positive effect on various sperm features and in vitro embryo development. However, native OVGP1 was found to have a more pronounced effect in comparison to recombinant non-glycosylated OVGP1 on various sperm functions except viability. Hence,our current findings infer that glycosylation of OVGP1 might be essential in sustaining the sperm functions but not the in vitro embryo development.  相似文献   
98.
Immature fruit of cultivated species of eggplant (Solanum melongena L.) are commonly used as a summer vegetable in India. Rich morphological variation exists among the cultivated species of eggplant in different growing regions of the country. We have characterised 24 breeding lines of Solanum spp., including 20 eggplant cultivars and four wild species of eggplant, based on 13 morphological characters using Mahalonabis D2 statistics. All 24 breeding lines of Solanum spp., including the 20 eggplant cultivars and four wild species, were grouped into four clusters by agglomerative clustering. Cluster II and Cluster IV contained the most accessions (eight each), while Cluster I and Cluster III had four accessions each. The highest inter-cluster (D2) distance (158.33) was observed between Cluster I and Cluster II, followed by Cluster I and Cluster III (108.48), and Cluster II and Cluster IV (102.96), which indicated that accessions in Cluster I and Cluster II were more divergent than those in the other clusters. The highest intra-cluster distance (5.80) was observed in Cluster IV, with eight genotypes, and the lowest intra-cluster distance (2.21) was observed in Cluster II, also with eight genotypes. The intra-cluster distances in all four clusters were lower than the inter-cluster distances, which indicated that genotypes within the same cluster were closely related. Genotypes in Cluster IV had the maximum number of flowers per cluster (3.63), the highest number of fruit per cluster (3.25), and number of fruit per plant (208.63), which revealed that genotypes could be selected from Cluster IV for these characters. The first three principal components (PC1, PC2, and PC3) accounted 73.99% of the total variation among the 24 genotypes. These phenotypic data increase the feasibility of prioritising breeding lines in a crossing programme based on the uniqueness of their desirable morphological traits.  相似文献   
99.
Insulin‐like growth factor‐binding protein‐3 (IGFBP‐3) is a protein that binds the majority of insulin‐like growth factors in circulation for regulation of its action on growth and metabolism of the animals. Animals belonging to Hariana, Holstein‐Friesian (HF) and their crossbreds (HF × Hariana) were studied using polymerase chain reaction‐restriction fragment length polymorphism and nucleotide sequencing of the IGFBP‐3 gene. A 651‐bp fragment of the IGFBP‐3 gene spanning over a part of exon 2, complete intron 2, exon 3 and a part of intron 3 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in HF and crossbred cattle revealing polymorphism in both the populations. The frequency of AA, AB and BB genotypes was 0.65, 0.32 and 0.03 in crossbreds and 0.29, 0.65 and 0.06 in HF respectively. The allelic frequency of the A and B allele was 0.81 and 0.19 in crossbreds and 0.62 and 0.38 in HF cattle respectively. Only one restriction pattern (AA genotype) was observed in all the animals of Hariana breed of Bos indicus showing the absence of polymorphism. Nucleotide sequencing revealed a C → A mutation in the intron 2 region of the IGFBP‐3 gene as the cause of the polymorphism. Least squares analysis revealed a significant effect (p < 0.05) of genotypes on birth weight and body weight (weight at 12, 18 and 24 months of age) of the animals. Animals of AB genotype showed higher birth weight and body weight than the animals possessing AA genotype.  相似文献   
100.
A field experiment was conducted to study the influence of boron (B) application on yield and B uptake of cotton (Gossypium hirsutum L.) in B-deficient calcareous soil of south-west Punjab. The treatments comprise six levels of soil-applied B (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 mg B kg?1soil) and two levels of foliar-applied B (0.1% and 0.2% borax and granubor solution) along with the common control (no B application). The experiment was laid out in RBD factorial design with three replications. The seed cotton yield and its attributing characters (plant height, number of sympodial and monopodial branches, boll weight, and number of boll per plant) and root biomass increased significantly with increasing levels of boron up to 1.0 mg B kg?1 level over the control and then remained nonsignificant with further higher levels of soil-applied boron. Among foliar-applied boron levels, 0.1% borax solution was better than 0.2% borax solution. Soil-applied boron was at par with foliar-applied boron. The efficiency of borax and granubor was found to be equal in both sources of boron. The mean B content and its uptake by seed cotton and roots increased significantly up to 1.0 mg B kg?1 soil-applied B level and then recorded nonsignificant with further higher levels of boron. For the foliar method of B application, the mean B content and its uptake by seed cotton increased significantly over the control. The mean available B content in soils (0–15 cm) at 45, 75, 105, and 145 days after sowing increased significantly over the control for all soil-applied B levels, while it remained nonsignificant over the control for all growth stages of cotton in foliar method of B application. Further, it was positively correlated with root biomass (r = 0.91), boron uptake by root (r = 0.98), and sympodial branch per plant (r = 0.81). The interaction of B application levels and sources was not significant for all studied traits. Regardless of B sources, B application had a significant effect on yield, yield attributes, and B uptake up to 1.0 mg B kg?1 level for soil-applied B and 0.1% borax or granubor solution for foliar-applied B.  相似文献   
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