Nano-calcium carbonate reinforced polypropylene and propylene-ethylene copolymer nanocomposites: Tensile vs. impact behavior

Improvement of both the tensile and impact strength of the same polymeric material has always been a great challenge for the plastic industry. The study focuses on the effect of incorporation of calcium carbonate nanoparticles (0.3 wt% to 15 wt%) into three polypropylene (PP) based matrices viz. PP homopolymer, propylene-ethylene (PP-PE) copolymer and the blend of PP:PP-PE (30:70) to improve their impact behavior without hampering the tensile strength much. A loss in both the tensile and impact properties was observed in PP based nanocomposite. However, PP-PE based nanocomposites showed a significant improvement in impact strength (47 %) at 10 wt% loading with a loss of tensile strength by 22 %. To minimize this loss a blend of PP:PP-PE (30:70) was explored as a matrix. At 10 wt% loading, this matrix showed an improvement of 30 % in impact strength whereas the tensile loss was minimized to 10 %. Further, silane coupling agent which promoted good interfacial adhesion was used for best compositions. The variation of crystalline morphology of the nanocomposites with various formulations was analyzed using differential scanning calorimetry and X-ray diffraction.     

Response of confection sunflower (Helianthus annuus L.) grown in a semi‐arid environment to planting date and early termination of irrigation

Adjustments on planting date and on the time to terminate irrigation may reduce agricultural water use. However, such management practices in regions with extreme weather conditions have the potential to negatively affect yield. A 3‐year (2012–2014) study was conducted on a clay‐loam soil in a cool, semi‐arid environment to (i) determine the response of confection sunflower to planting date and irrigation termination timing and (ii) identify the relative importance of yield components in irrigated confection sunflower across planting dates. Early May planting had considerable negative effects on all studied variables, except on the percentage of large seeds. The highest yield of total and large seeds was obtained from the late May plantings, averaging 3,777 and 3,379 kg/ha, respectively. None of the irrigation strategies affected the measured variables. However, the interaction between planting date and termination of irrigation significantly affected the 1,000‐seed weight. Our study revealed the last week of May as suitable planting period for confection sunflower in the semi‐arid north‐western region of Wyoming, USA, and that irrigation on heavy soils may be terminated as early as at R5.5 stage without a significant yield reduction. The path‐coefficient analysis indicated head diameter and the number of seeds per head as important traits that significantly influence the yield of confection sunflower across planting dates.     

Breeding crops for reduced-tillage management in the intensive, rice–wheat systems of South Asia

The importance of reduced tillage in sustainable agriculture is well recognized. Reduced-tillage practices (which may or may not involve retention of crop residues) and their effects differ from those of conventional tillage in several ways: soil physical properties; shifts in host–weed competition; soil moisture availability (especially when sowing deeply or under stubble); and the emergence of pathogen populations that survive on crop residues. There may be a need for genotypes suited to special forms of mechanization (e.g. direct seeding into residues) and to agronomic conditions such as allelopathy, as well as specific issues relating to problem soils. This article examines issues and breeding targets for researchers who seek to improve crops for reduced-tillage systems. Most of the examples used pertain to wheat, but we also refer to other crops. Our primary claim is that new breeding initiatives are needed to introgress favourable traits into wheat and other crops in areas where reduced or zero-tillage is being adopted. Key traits include faster emergence, faster decomposition, and the ability to germinate when deep seeded (so that crops compete with weeds and use available moisture more efficiently). Enhancement of resistance to new pathogens and insect pests surviving on crop residues must also be given attention. In addition to focusing on new traits, breeders need to assess germplasm and breeding populations under reduced tillage. Farmer participatory approaches can also enhance the effectiveness of cultivar development and selection in environments where farmers’ links with technology providers are weak. Finally, modern breeding tools may also play a substantial role in future efforts to develop adapted crop genotypes for reduced tillage.     

Über die Abhängigkeit der Eizahl und Entwicklung des Getreideplattkäfers,Oryzaephilus mercator Fauv. (Col., Cucujidae) von der Nahrung

The oviposition and development of the grain bettle Oryzaephilus mercator Faur.on dry fruit meals. Oryzaephilus mercator showed enormous variation in egg laying on different dry fruit meals (apricot, cashew, almond, groundnut, coconut, fig, date and raisin). The lowest egg period was 4.1 days on almond and the highest on apricot 5.1 days. The egg mortality on various meals differed to a small extent (11.8 to 14.1%). The larval period ranged between 22.7 to 34.3 days. The larval mortality ranged between 7.8% (almond) to 94.4% (raisin).     

Effect of irrigation on tillering in wheat,triticale and barley in a water-limited environment

Summary The effect of irrigation on tillering and tiller mortality in varieties of wheat (Triticum aestivum and T. durum), triticale and barley was studied under field conditions. Low temperature in the early stages of growth promoted production of tillers whereas increase in temperature during extension growth phase increased tiller mortality. More than 1000 tillers m^–2 were produced with five irrigations but 40% or more died. With limited water availability tiller production was reduced but so was their mortality. Grain yield in wheat and triticale was positively correlated with productive tillers and negatively correlated with the maximum number of tillers produced in wheat and barley grown under limited irrigation conditions. Varieties with a capacity to produce fewer tillers were identified. Some of them proved more stable in yield. No correlation was found between tiller number and grain yield in the frequently irrigated treatment.     

Efficacy of an indigenous formulation in patients with bleeding piles: a preliminary clinical study.

The results of the clinical assessment of a multiherbal indigenous formulation on 22 patients with bleeding piles are reported.     

印度加瓦尔喜马拉雅山的亚热带的宽叶榆绿木(Anogeissus latifolia)林恢复状况(英文)

研究了位于印度加瓦尔海平面(950～1100m)上的亚热带森林的再生生长状况。对生长在不同方位(东、西、北、南)研究地的植被进行了定量分析。研究结果表明:宽叶榆绿木(Anogeissus latifolia)的树木、幼树和幼苗层在研究地点的所有方位显生长优势。长叶松(Pinusroxburghii)和毛白杨(Terminalia tomentosa)的树木、小树在研究地点的北部显生长优势。树木层的最高(380株·ha-1)和最低密度(260株·ha-1)分别出现在南坡和北坡。幼树的最高(1790株·ha-1)和最低密度(970株·ha-1)分别出现在东坡和西坡。树木和灌木层的多样性分别为0.846～1.710和1.943-2.847。与其它种的相比较(4%～33%),宽叶榆绿木(Anogeissus latifolia)的相对剪枝强度较高(45%-57%),此种是在北坡中最重要的树种。目前研究表明,如果不合理开采继续进行,宽叶榆绿木(Anogeissus latifolia)就有可能被其他种代替,在树种的成分和森林重建方面会发生剧烈的变化。人类活动的压力,地理方位和土壤营养已引起了树种的成分和森林重建方面的变化。     

Knowledge, attitudes and practices of farmers on rodent pests and their management in the lowlands of the Sierra Madre Biodiversity Corridor, Philippines

A survey of the knowledge, attitudes and practices (KAP) of 100 rice farmers and 50 coconut farmers was conducted in the coastal lowland agro-ecosystems of the Sierra Madre Biodiversity Corridor, Luzon, Philippines to identify current rodent management practices and to understand the extent of rat damage and the attitudes of farmers to community actions for rodent management. Pests were most commonly listed as one of the three most important rice and coconut production constraints. Other major crop production constraints were typhoons and insufficient water. Farmers consider rats to be the major pest of coconut and of rice during the wet season rice crop, with average yield losses of 3.0% and 13.2%, respectively. Rice and coconut farmers practised a wide range of rodent management techniques. These included scrub clearance, hunting and trapping. Of the 42 rice farmers and 3 coconut farmers that applied rodenticides to control rodents, all used the acute rodenticide, zinc phosphide. However, only ten rice farmers (23.8%) applied rodenticides prior to the booting stage and only seven farmers (15.6%) conducted pre-baiting before applying zinc phosphide. The majority of farmers belonged to farmer organisations and believed that rat control can only be done by farmers working together. However, during the last cropping season, less than a third of rice farmers (31.2%) applied rodent management as a group. In order to reduce the impact of rodents on the farmers of the coastal lowlands of the Sierra Madre Biodiversity Corridor, integrated management strategies need to be developed that specifically target the pest rodents in a sustainable manner, and community actions for rodent management should be promoted.