Effects of maize (Zea mays L.) silage feeding on dry matter intake and milk production of dairy buffalo and cattle in Tarai, Nepal

To identify the effects of whole crop maize silage (MS) as a substitute for rice straw (RS) on feed intake and milk production of mid-late lactating buffalo and cattle in Tarai, Nepal, eight Murrah and eight Jersey-Hariana were fed the basal diet, RS ( ad libitum ) with concentrate (0.68% of bodyweight [BW] on a dry matter [DM] basis). A 4 × 4 Latin square design experiment was conducted in each animal species with graded levels of MS substitution for RS (0%, T1; 33%, T2; 67%, T3 and 100%, T4). The MS had higher digestibility and total digestible nutrient (TDN) than RS. The DM intake per BW of the both species was highest in T3. The substitution of MS for RS increased the crude protein intake and the TDN intake in the both species. Although the buffalo showed the highest milking performance in T4, the cattle showed no significant differences in their milking performance among the treatments. The substitution of MS for RS improved the feed intake and milk production in the buffalo. On the other hand, the milk yield was not raised in the cattle, though the feed intake was increased by the substitution.     

Effects of haemorrhagic septicaemia vaccination and levamisole administration on the humoral response in cross-bred calves

Levamisole administered by oral, subcutaneous or transdermal routes following vaccination against Pasteurella multocida enhanced the humoral response in cross-bred calves. The group that received levamisole subcutaneously elicited highly significant (P less than 0.01) antibody titres during the primary humoral response in comparison with groups that received levamisole orally or transdermally. During the secondary response in the same experiment, levamisole administered subcutaneously and transdermally showed highly significant (P less than 0.01) haemagglutination titres relative to oral administration of the drug. In a second experiment, the group that received levamisole subcutaneously showed highly significant (P less than 0.01) antibody titres during the anamnestic humoral response over other treated groups.     

Effect of Heterodera cajani on biomass and grain yield of pigeon pea on vertisol in pot and field experiments

Glasshouse and field trials were conducted to determine the effects of the cyst nematode, Heterodera cajani on biomass and grain yield of pigeon pea, Cajanus cajan. Shoot length, fresh and dry shoot masses, leaf area and pod yields of pigeon pea were significantly reduced by H. cajani. In glasshouse pot experiments, an initial density of 1.0 juveniles per cm³ soil caused 14 to 24% reduction in plant height, root and shoot mass and leaf area. Application of carbofuran 3G (1·5, 3·0 and 6·0 kg a.i./ha) in H. autoclaved soil in pots did not improve growth of pigeon pea; however, its application (6 kg a.i./ha) in H. cajani -infested fields reduced the nematode density ( P < 0·05) and improved plant growth and yield. The densities of eggs and juveniles of H. cajani were 72 and 48% lower in the carbofuran-treated plots than in the control plots 35 and 52 days, respectively, after sowing. No such differences were observed at 70 days after sowing. The tolerance limit for pod yield in field experiments was 2·6 eggs and juveniles of H. cajani per cm³ soil at sowing time. Grain yield was 20 to 25% higher in the carbofuran-treated plots than in the control plots. Application of carbofuran protected the roots from nematode damage during the early stages of plant growth and resulted in good plant growth and yield.     

Silicon and plant nutrition—dynamics,mechanisms of transport and role of silicon solubilizer microbiomes in sustainable agriculture: A review

Silicon (Si) is the second most abundant element in the Earth’s crust and has numerous roles in both soils and plants, although it is inaccessible to plants in its native state (insoluble silicate minerals). This inaccessibility can lead to insufficiency, which induces anomalies in plant growth and development.Specifically, Si alleviates various biotic and abiotic stresses in plants by enhancing tolerance mechanisms at different stages of uptake/deposition as a monosilicic acid. Exclusive utiliz...     

使用便携式X射线荧光（PXRF）法原位区分酸性和非酸性冻土带

Frozen soils or those with permafrost cover large areas of the earth’s surface and support unique vegetative ecosystems. Plantsgrowing in such harsh conditions have adapted to small niches, which allow them to survive. In northern Alaska, USA, both moistacidic and non-acidic tundra occur, yet determination of frozen soil pHs currently requires thawing of the soil so that electrometric pHmethods can be utilized. Contrariwise, a portable X-ray fluorescence (PXRF) spectrometer was used in this study to assess elementalabundances and relate those characteristics to soil pH through predictive multiple linear regressions. Two operational modes, SoilMode and Geochem Mode, were utilized to scan frozen soils in-situ and under laboratory conditions, respectively, after soil sampleswere dried and ground. Results showed that lab scanning produced optimal results with adjusted coefficient of determination (R²) of0.88 and 0.33 and root mean squared errors (RMSEs) of 0.87 and 0.34 between elemental data and lab-determined pH for Soil Modeand Geochem Mode, respectively. Even though the presence of ice attenuated fluoresced radiation under field conditions, adjusted R² and RMSEs between the datasets still provided reasonable model generalization (e.g., 0.73 and 0.49 for field Geochem Mode). Principalcomponent analysis qualitatively separated multiple sampling sites based on elemental data provided by PXRF, reflecting differences inthe chemical composition of the soils studied. Summarily, PXRF can be used for in-situ determination of soil pH in arctic environments without the need for sample modification and thawing. Furthermore, use of PXRF for determination of soil pH may provide highersample throughput than traditional eletrometric-based methods, while generating elemental data useful for the prediction of multiplesoil parameters.     

Role of beneficial microbial gene pool in mitigating salt/nutrient stress of plants in saline soils through underground phytostimulating signalling molecules

Soil salinity diminishes soil health and reduces crop yield, which is becoming a major global concern. Salinity stress is one of the primary stresses, leading to several other secondary stresses that restrict plant growth and soil fertility. The major secondary stresses induced in plants under saline-alkaline conditions include osmotic stress, nutrient limitation, and ionic stress, all of which negatively impact overall plant growth. Under stressed conditions, certain beneficial soil microflora ...     

Socio-economic importance, domestication trends and in situ conservation of wild Citrus species of Northeast India

Northeast India is rich in Citrus genetic diversity representing several wild and cultivated species. Besides commercially cultivated species, several wild, semi-wild and domesticated species namely Citrus indica, C. macroptera, C. ichangensis, C. latipes, C. megaloxycarpa and C. assamensis are found to grow in Northeast India. These species have great potential in improvement of Indian Citrus industry being source of genes for combating biotic and abiotic stresses. The natural diversity of these genetic resources is shrinking at alarming rate due to large scale deforestation, shifting cultivation practiced in these areas and climate change scenario in this important hotspot of biodiversity. Socio-economic importance of each species have been studied during surveys and interesting domestication trends were observed based on their cultural and economic significance, which led to “in situ on farm” conservation of C. indica, C. macroptera and threat to C. megaloxycarpa and C. ichangensis. Consequently, genetic resources of most of these species are facing severe threat of extinction necessitating policy interventions and adoption of dynamic conservation and management strategies. Species specific conservation strategy especially through “in situ on farm” conservation has been proposed with suitable sites in Northeastern Indian states based on population structure and suitability of habitat. Farmers’ support through “The Biological Diversity Act, 2002” and “The Protection of Plant Varieties and Farmers’ Rights Act, 2001” of India would bring the required impact on management of these complex genetic resources of Citrus. In the present study, we have documented the current status, socio-economic potential, domestication trends and associated traditional knowledge of these wild and semi-wild Citrus species occurring in Northeast India and enumerated suitable conservation strategies and desired policy interventions for their dynamic conservation and sustainable utilization.     

Genetic diversity in <Emphasis Type="Italic">Eremostachys superba</Emphasis> Royle ex Benth. (Lamiaceae), an endangered Himalayan species,as assessed by RAPD

Eremostachys superba Royle ex Benth. (Lamiaceae) has undergone a severe decline in population size since its discovery in the North-western Himalayas in late 19th century. One hundred and seventy-two plants from six populations in the Indian states of Uttar Pradesh and Jammu & Kashmir, located between 0.45 km and 455.72 km apart from each other were evaluated for RAPD polymorphism. Sixteen random primers generated 92 bands overall, 77 of which were polymorphic. Shannon’s index of genetic diversity within populations (H _o) ranged between 0.305 and 0.421; the average within-population diversity (H _pop) was 0.389; and the total species diversity (H _sp) was 0.478. The population from Mohand (representing the type locality) had the fewest plants, at 18, and was genetically the most depauperate. Among the other populations, ranging in size between 52 and 1,022 individuals, no relation between population size and genetic diversity was evident. It is suggested that these six populations represent relics of a larger, extended population, in which the presence of perennating rootstocks has helped preserve historic patterns of genetic diversity. AMOVA revealed that 83.01% of the variation exists within populations, which was consistent with earlier studies on the reproductive biology of E. superba, which indicated this species is predominantly allogamous. FST distances between all populations were significant, indicating geographic differentiation despite some of them being closely separated. Habitat restoration and protection from indiscriminate harvesting are proposed as primary strategies for conserving E. superba. Rejuvenation of the Mohand population through intrapopulation crossing between plants bearing diverse molecular phenotypes is also suggested.     

Detection of arboviruses in Culicoides(Diptera: Ceratopogonidae) collected from animal farms in the border areas of Yunnan Province,China

Biting midges of the genus Culicoides(order Diptera, family Ceratopogonidae) are potential biological vectors for the transmission of certain arboviruses among humans, livestock, and wild animals. This study collected a total of 405 Culicoides individuals from seven animal farms located in five counties in the border areas of Yunnan Province, China, and examined the Culicoides species composition and the major arboviruses carried by the Culicoides species. The collected Culicoides were classified into seven species with variable abundances: Culicoides arakawae(5.43%, 22/405), Culicoides homotomus(1.23%, 5/405), Culicoides obsoletus(19.75%, 80/405), Culicoides orientalis(17.28%, 70/405), Culicoides oxystoma(29.38%, 119/405), Culicoides peregrinus(5.68%, 23/405), and Culicoides nipponensis(21.23%, 86/405). Among the seven species, C. oxystoma and C. nipponensis were distributed in all the five counties with abundances of 13.33–44.87% and 10.00–46.83%, respectively, suggesting that these were the dominant species of Culicoides widespread on animal farms in the border areas. PCR was used to detect major arboviruses in the collected Culicoides specimens, including bluetongue virus(BTV), Japanese encephalitis virus, Dengue virus, Zika virus, African swine fever virus, and African horse sickness virus. Among the tested viruses, only BTV serotype 1 was tested positive in C. oxystoma specimens collected from a buffalo farm. Culicoides oxystoma was the dominant species on animal farms in the sampled areas, but it has not previously been documented as positive for BTV in China. The current results thus suggest that C. oxystoma could be an important vector for BTV transmission in these border areas, which, however, needs to be confirmed by further comprehensive experiments. Overall, the present study provides the first profile of Culicoides species on animal farms in the China, Vietnam, and Myanmar border areas, establishes the prevalence of arboviruses carried by these Culicoides species, and suggests the vector potential of C. oxystoma species for the transmission of BTV.