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71.
Anup Das Savita Basavaraj Jayanta Layek Ramkrushna Gandhiji Idapuganti Rattan Lal Krishnappa Rangappa 《Archives of Agronomy and Soil Science》2020,66(6):830-846
ABSTRACTLow productivity and energy use efficiency (EUE) of rice farming are the major concerns for agricultural sustainability in the Eastern Himalayan region of India. A field experiment on rice (Oryza sativa L.)-pea (Pisum sativum L) system was conducted for three consecutive years during 2012–15 in lowland ecosystem to assess the direct and residual impact of tillage and residue management (RM) practises on productivity and sustainability. Significantly higher grain yield of rice was achieved under no-till (NT) than minimum tillage (MT) and conventional tillage (CT). Among RM practises, 50% NPK + green leaf manure, 50% NPK + weed biomass and 50% NPK + in-situ residue retention recorded significantly higher mean grain yields than application of 50% NPK and 100% NPK without residues. Residual effect of MT in preceding rice gave significantly higher green pod yield of succeeding pea than NT and CT. The system EUE was significantly higher under MT (rice)-NT (pea) compared to those of NT-NT and CT-NT systems. The sustainable yield index of rice and pea was maximum under MT-NT followed by NT-NT. Thus, NT/MT with suitable RM practises is a pertinent strategy for sustainable productivity of rice-pea system in the Eastern Himalayas and in similar adjoining regions. 相似文献
72.
73.
A. Josephrajkumar Chandrika Mohan J. Poorani Merin Babu Daliyamol V. Krishnakumar Vinayaka Hegde P. Chowdappa 《Phytoparasitica》2018,46(1):57-61
Scavenging action of Leiochrinus nilgirianus Kaszab (Coleoptera: Tenebrionidae) on sooty mould deposition on coconut palms due to heavy honeydew production by the invasive rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae), is reported for the first time from Kerala, India. Adult beetles, averaging 2.07?±?0.9 / leaflet, with a maximum of five beetles per leaflet, and immature stages were generally confined to the abaxial of the palm leaves during daytime, but were found feeding on sooty mould during morning hours in damp conditions. The specially aided adaptive leg features of L. nilgirianus with bristle-like hairs on the undersurface of tarsomeres probably aid in proper adhesion on sooty mould laden plant surface and well developed tarsal claws that perhaps assist swift movement on fungus-laden leaflets. On an average one adult beetle could clear 1–2 mm2 sooty mould laden area in a period of one minute. In situ habitat conservation of L. nilgirianus would help to reduce the sooty mould at no cost in the most natural and eco-friendly manner avoiding chemical management options and other expensive methods. 相似文献
74.
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76.
Mengyun Liu David A. N. Ussiri Rattan Lal 《Communications in Soil Science and Plant Analysis》2016,47(12):1528-1541
Many questions have surfaced regarding long-term impacts of land-use and cultivation system on soil carbon (C) sequestration. The experiment was conducted at Ohio Agricultural Research and Development Center. Only minor variations of soil organic carbon (SOC) and nitrogen (N) fractions with depth under plow tillage (PT). The SOC, total nitrogen (TN), microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) concentrations were higher under grassland and forestland in the top 0–15 cm depth than arable soils. No-tillage (NT) also increased SOC and N fractions concentrations in the surface soils than PT. Compared to arable, grass and forest could significantly improve proportions of MBC and MBN, and reduce proportions of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). NT and forest also increased the ratio of SOC/TN, MBC/MBN, and DOC/DON. Overall, grass and forest provided more labile C and improved C sequestration than arable. So did NT under arable land-use. 相似文献
77.
S. T. Thul R. K. Lal A. K. Shasany M. P. Darokar A. K. Gupta M. M. Gupta R. K. Verma S. P. S. Khanuja 《Euphytica》2009,168(2):189-196
Phenotypic divergence among the 24 accessions belonging to a collection of six species of Capsicum from different geoclimatic regions available in field gene bank of CIMAP, Lucknow, India, was quantified by multivariate
analysis for 12 quantitative and qualitative traits. Based on their values, all 24 accessions were grouped into six clusters
such that the genetic stocks within cluster had smaller D
2 values among themselves than those belonging to different clusters. The accessions of Capsicum annuum were distributed in different clusters in morphotyping representing different species, suggesting that taxonomic characteristics
are not always related to agronomic traits. No parallelism/association was found between geographical and phenotypic diversity.
Accessions 15 and 23 (clusters V and VI, respectively) had distinct identity. The three characteristics that played the greatest
role in differentiation were fruit diameter, number of fruits per plant, and leaf diameter, which can be utilized as conventional/morphological
markers for the improvement of chilli yield and obtaining good segregants in chilli breeding programs. 相似文献
78.
Several SNP (single nucleotide polymorphism) genotyping methods have been developed in the past most of which require sophisticated instrumentation and large initial investments. We describe here a high-throughput SSCP (single strand conformation polymorphism) system on our HEGS (high efficiency genome scanning) platform, which is simple, accurate, cost effective and requires neither restriction digestion of the amplification products nor elaborate post-PCR processing detection. Several parameters critical to SSCP analysis were optimized viz., gel matrix and concentration, gel running temperature, buffer composition, running conditions and PCR primer design so as to identify SNPs in amplicons ranging from 100 to 750 bp in size. A simple post-PCR processing system was developed using fluorescent dye for quick and easy detection of SNP polymorphism. HEGS-SSCP was also found to be useful in uncovering simple sequence repeat differences between different genotypes that differ by one or few di/tri nucleotide repeats. The practical utility of this system is illustrated with two successful efforts towards construction of high resolution linkage maps of a lesion mimic locus on chromosome 7 and a major quantitative trait locus conditioning field blast resistance on chromosome 4 in rice. 相似文献
79.
This article elucidates the effect of crude dietary aflatoxin B1 (AFB1) on the stability of the lysosomal membrane in tilapia (Oreochromis mossambicus), and the analysis was made at the biochemical and cellular level. The liver lysosomal acid phosphatase activity was used to evaluate the functional integrity of the lysosome. Three experimental groups were fed on diets containing 0.375, 2.5 and 6 mg kg?1 of AFB1 for a time period of 6 weeks, whereas a fourth group fed on the semi‐purified diet formed the control. Significant changes were observed in the stability of the lysosomal membrane in aflatoxin exposed groups. This is the first report, so far, of changes induced by AFB1 on the stability of lysosomal membrane in tilapia (O. mossambicus). 相似文献
80.
Ravi Charan Padinhate Purayil Suresh Babu Gundaboena Venugopal Narinder Kumar Chadha Kommula Bhaskara Sreeramamurty 《Aquaculture International》2014,22(2):689-697
In India, many of the fish farmers stock 1-year-old stunted fishes (stunted yearlings) of Indian major carps (IMC) for enhancing fish production through compensatory growth, but many of them observed problems of early maturation in these fishes. Application of aromatase inhibitors for deceleration of ovarian maturation is one of the probable solutions to mitigate this issue. In the present study, a synthetic aromatase inhibitor letrozole [25 (L25) and 50 (L50) mg kg?1 feed] and a plant-derived aromatase inhibitor, grape seed extract [100 (G100) and 200 (G200) mg kg?1 feed], were fed to stunted yearlings of rohu (Labeo rohita) for 45 days well before the onset of breeding season. Maturation indices such as gonadosomatic index (GSI) and serum oestradiol (E) levels indicated a dose-dependent inhibition of ovarian development in the aromatase-inhibitor-treated fish. Higher dose of letrozole (GSI, 15.12 ± 0.18; E, 3.19 ± 0.42) and grape seed extract (GSI, 16.90 ± 0.40; E, 3.60 ± 0.75) were found to be more effective since control fish showed further advancement in maturation (GSI, 21.20 ± 1.10; E, 7.33 ± 0.74) during the peak breeding season (15th June). Histological observations also confirmed the results revealing a delayed initiation of ovarian development in the case of higher doses of letrozole and grape seed extracts. These results indicate the possible use of aromatase inhibitors in arresting the early maturation process in IMC. 相似文献