• Title/Summary/Keyword: Semi-Arid

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Effects of Soil Amendments on Survival Rate and Growth of Populus sibirica and Ulmus pumila Seedlings in a Semi-arid Region, Mongolia (몽골 반건조 지역에서 토양 개량이 백양나무와 비술나무 묘목의 활착 및 생장에 미치는 영향)

  • Jung, Yegi;Yoon, Tae Kyung;Han, Saerom;Kang, Hoduck;Yi, Myong-Jong;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.103 no.4
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    • pp.703-708
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    • 2014
  • This study was conducted to investigate effects of soil amendments on survival rate and growth of seedlings in a semi-arid region, Mongolia. 2-year-old Populus sibirica and Ulmus pumila seedlings were planted in alkaline sandy soils and treated with 2 levels of nitrogen, elemental sulfur, artificial moisture retention and converted loess. After 4 months, the seedling survival rate of both species decreased as the amount of nitrogen increased. Nitrogen has been generally known to increase seedling survival rate and growth by supplying nutrients, however, reduced survival rate in this study might be affected by consequential increase in soil osmotic pressure, which was caused by excessive nitrogen fertilization. The root collar diameter (RCD) growth of both species increased significantly by the treatment of converted loess, and only RCD growth of P. sibirica increased by the artificial moisture retention treatment. Although P. sibirica is drought-tolerant, it is in the group of Populus spp. which requires a high capacity of available water. Conversely, the elemental sulfur treatment showed no effect on survival rate and RCD growth for both species due to the low oxidation of sulfur in arid soils. The extended monitoring of seedling growth and soil characteristics is required to elucidate the long-term effects of soil amendments in the semi-arid region, and the further studies are also needed to examine the appropriate amount of fertilizers for both species.

EFFECT OF SEASON ON SEMINAL CHARACTERISTICS OF HOLSTEIN BULL UNDER SEMI-ARID ENVIRONMENT II. SPERM ABNORMALITIES

  • Salah, M.S.;El-Nouty, F.D.;Al-Hajri, M.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.3
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    • pp.449-454
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    • 1992
  • Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the incidence of the morphologically abnormal spermatozoa. Semen was collected twice a week by A. V. over one-year period. The percentage of total abnormal spermatozoa was $14.1{\pm}0.5$. Ejaculates collected during hot summer season had significantly higher incidence of abnormal spermatozoa than those collected during winter time. Warm spring had moderate semen abnormality. In addition to its effect on the total number of morphologically abnormal spermatozoa, season affected significantly the primary as well as the secondary types of abnormalities. The differences between incidence of primary and secondary types of abnormalities were not significant for all seasons and seasons pooled together. The ratio between the total forms of abnormality in the head, mid-piece and tail of spermatozoa was as 1:1.5:1. Head and mid-piece had defected more during summer compared with both winter and spring. There was no variation in tail abnormalities due to season. The significant effect of season on head was observed by large, pyriform, free and detached heads, while that on mid-piece was by swollen, coiled mid-pieces and protoplasmic droplets.

EFFECT OF SEASON ON SEMINAL CHARACTERISTICS OF HOLSTEIN BULL UNDER SEMI-ARID ENVIRONMENT I. BIOPHYSICAL CHARACTERISTICS

  • Salah, M.S.;El-Nouty, F.D.;Al-Hajri, M.R.;Mogawer, H.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.3
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    • pp.439-447
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    • 1992
  • Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the biophysical characteristics of semen. Semen was collected twice a week by AV (artificial vagina) over one-year period. The analyses revealed that all the basic seminal traits studied were differed significantly due to season, except the ejaculate volume and consistency and the percentage of swollen spermatozoa in a hypo-osmotic fructose-citrate solution. Ejaculates collected during hot summer season had significantly lower sperm motility, concentration and total counts, and higher percentage of dead spermatozoa than those collected during winter time. Warm spring had moderate semen quality. The temperature-humidity index was calculated and it was associated (p < 0.01) negatively with the ejaculate pH, sperm concentration and total counts, and positively with the % of dead sperms. Ejaculate volume, percentage of swollen spermatozoa, individual motilities did not correlate significantly with the change in temperature-humidity index values. The total live, motile spermatozoa per ejaculate during both the winter and spring seasons showed significant increase of about 37% and 32% respectively over the summer season. Also, rectal temperatures of the bulls were elevated during the hot summer season, while the values of blood hemoglobin and packed-cell volume were decreased.

Characterization of Sclerospora graminicola Isolates from Pearl Millet for Virulence and Genetic Diversity

  • Pushpavathi B.;Thakur R. P.;Rao K. Chandrashekara;Rao V. P.
    • The Plant Pathology Journal
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    • v.22 no.1
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    • pp.28-35
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    • 2006
  • Virulence and genetic diversity were studied using 21 isolates of Sclerospora graminicola, the pearl millet downy mildew pathogen collected from major pearl millet growing areas of India. Variability for virulence was determined by inoculating a set of 10 differential hosts with the S. graminicola isolates in a greenhouse. The isolates varied for latent period (6.4 to 11 days), disease incidence (0 to $98\%$), virulence index (0 to 18.7) and oospore-production potential (1 to 4). Among the 21 isolates, Sg 139 (Rajasthan) was the most virulent and Sg 110 (Tamil Nadu) the least virulent. Based on virulence index (disease incidence$\time$slatent $period^{-1}$), the 21 isolates were classified into eight virulence groups. Genetic diversity among isolates was studied using AFLP markers. Based on similarity index of banding pattern, the 21 isolates were clustered into eight genotypic groups. The AFLP groupings, however, did not match with that of the virulence groupings, and these two were found independent. The isolate Sg 139 that remained distinct in both pathogenic and genetic groupings indicated its highly virulent nature. Implications of these results in downy mildew resistance breeding are discussed.

Seasonal Variations in Tannin Profile of Tree Leaves

  • Rana, K.K.;Wadhwa, M.;Bakshi, M.P.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.8
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    • pp.1134-1138
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    • 2006
  • Forest tree leaves (12 different species) of semi hilly arid region of Punjab State were collected at 30-day interval throughout the year to assess the seasonal variations in tannin profile. Tannins were extracted and fractionated from fat free samples and data were analyzed statistically by $12{\times}12$ factorial design. The leaves of Anogeissus latifolia had the highest (p<0.05) concentration of total phenols (17.4%), net (15.9%) and hydrolysable (16.9%) tannins, followed by leaves of Acacia nilotica. Majority of the tree leaves selected had moderate levels (2-5%) of net tannins. Leaves of Carrisa had the highest (p<0.05) concentration of condensed tannins (CT), whereas the leaves of Anogeissus had the lowest (p<0.05) concentration of condensed tannins. The protein precipitable phenols (PPP) corresponded well with the net tannin content present in different tree leaves. Seasonal variation data revealed that in summer, net tannins and PPP decline in leaves of Bauhinia and Zizyphus whereas the net tannin content of Anogeissus and that of Carrisa increased during summer. The CT and PPP content in the leaves of Pheonix, Leucaena, Zizyphus and Ougenia increased in winter till spring season. Tree leaves generally had higher concentration of HT during summer months. It was concluded that leaves of leaves of A. nilotica, A. latifolia and L. leucocephala could serve as an excellent alternate feed stuffs for ruminants. However, leaves of Phoenix, Carrisa, Bauhinia and Dodonea should be avoided.

Effect of Plant Population Densities on the Severity of tate Leaf Spot and Rust of Groundnut

  • Pande, S.;Rao, J.Narayana
    • The Plant Pathology Journal
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    • v.18 no.5
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    • pp.271-278
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    • 2002
  • The effect of five plant population densities [5 (D$_1$), 10 (D$_2$), 20 (D$_3$), 30 (D$_4$), and 40 (D$_{5}$) plants/m$^2$] of four groundnut cultivars [ICGV 86699, ICG (FDRS) 10, ICGS 11 and TMV 2] and fungicide application (Kavach, chlorothalonil) to manage late leaf spot (LLS) and rust were studied in a field experiment during the 1995 and 1996 rainy seasons. LLS and rust severities were low in fungicide sprayed plots in all the cultivars irrespective of plant densities. Severities of LLS and rust, and percentage defoliation caused by LLS were significantly more in higher plant densities (D$_4$, D$_{5}$) than in lower plant densities (D$_1$, D$_2$, D$_3$) in fungicide sprayed and unsprayed plots in all the cultivars. All the cultivars gave significantly higher haulm and pod yields in fungicide sprayed plots than in unsprayed plots. Haulm and pod yields were significantly higher in higher plant densities than in lower plant densities. A combination of higher plant densities (D$_4$, D$_{5}$) and fungicide protection against LLS and rust gave maximum yield.yield.

Power Pursuits: Interstate Systems in Asia

  • Palat, Ravi Arvind
    • Asian review of World Histories
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    • v.1 no.2
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    • pp.227-263
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    • 2013
  • Examining the patterns of evolution of interstate systems in Asia, this article argues that the relationship of state-builders to nomads stood in much of continental Asia stood in sharp contrast to the relationships between rulers and mercantile-financial elites in Europe. Due to the productivity of wet-rice economies, continental Asian rulers were not dependent on merchants and bankers to raise armies to wage war or suppress rebellions unlike their European counterparts. Hence they had no need to grant bankers and merchants concessions, especially monopolies which is how large volumes of capital are accumulated. Geographic conditions however meant that while the lack of internal frontiers meant that large continental-sized states could be created in China, this was not possible in the Indian subcontinent where a more chequered equilibrium where nomads enjoyed a military advantage in arid and semi-arid tracts meant that trans-subcontinental polities enjoyed only a fleeting existence. In mainland southeast Asia, where dense forests and a difficult terrain insulated the region from nomadic conquests, a third variant of interstate relations emerged.

Crop-Animal Production Systems in Tropical Regions - Review -

  • Devendra, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.2
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    • pp.265-276
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    • 2000
  • Crop-animal systems which form the backbone of agriculture in the tropics are discussed with reference to their characteristics, economic importance of animals, genesis and types of crop-animal systems, relevance and potential importance, and priorities for research and development. These production systems are found across all agroecological zones: rain-fed temperate and highland systems, semi-arid and arid tropics, and sub-humid and humid tropics: the last four are priority areas in Asia. The potential importance of these systems in Asia is reflected in their advantages, synergism and complimentarity, economic benefits and contribution to sustainability. Illustrative case studies are cited which are appropriate to the two broad types of mixed farming systems: systems combining animals and annual cropping, and systems combining animals with perennial cropping with reference to Indonesia, Philippines, Malaysia, Sri Lanka, China and Nigeria. Priorities for research and development should address more complete use of the animal genetic resources, intensive utilisation of the feed resources, development-oriented utilisation of research results, minimizing animal diseases, and implementation of appropriate institutional and policy issues.