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81.
82.
Tropical Animal Health and Production - 相似文献
83.
Bitter gourd or bitter melon (Momordica charantia L.) is considered as minor cucurbitaceous vegetable in spite of having considerable nutritional and medicinal properties. Although some reports on genetic diversity based on morphological characterization are available, no work has been conducted to estimate genetic diversity using molecular markers in this crop. In the present study, 38 genotypes of M. charantia including few commercially cultivars collected from different parts of India based on agro-ecological zones were analysed for diversity study both at morphological and molecular levels. Genomic DNA was extracted from young healthy leaves following the procedure of Doyle and Doyle [Doyle, J.J., Doyle, J.L., 1990. A rapid DNA isolation procedure from small quantity of fresh leaf material. Phytochem. Bull. 119, 11–15]. Pair-wise comparison of genotypes was calculated as per the procedure of Jaccard [Jaccard, P., 1908. Nouvelles recherches sur la distribution florale. Bull. Soc. Vaud. Sci. Nat. 44, 223–270]. Dendrogram was constructed using the unweighted pair group method with arithmetic averages (UPGMA) and the computation for multivariate analysis was done using the computer programme NTSYS-pc Version 2.0 [Rohlf, F.J., 1998. NTSYS-pc Numerical Taxonomy and Multivariate Analysis System, Version 2.01. Exeter Software, Setauket, NY, USA]. Diversity based on yield related traits and molecular analysis was not in consonance with ecological distribution. Among 116 random decamer primers screened 29 were polymorphic and informative enough to analyse these genotypes. A total of 208 markers generated of which 76 (36.50%) were polymorphic and the number of bands per primer was 7.17 out of them 2.62 were polymorphic. Pair-wise genetic distance (GD) based on molecular analysis ranged from 0.07 to 0.50 suggesting a wide genetic base for the genotypes. The clustering pattern based on yield related traits and molecular variation was different. 相似文献
84.
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. 相似文献
85.
G. Girmay B. R. Singh H. Mitiku T. Borresen R. Lal 《Land Degradation \u0026amp; Development》2008,19(4):351-367
The effect of soil management and land use change are of interest to the sustainable land management for improving the environment and advancing food security in developing countries. Both anthropogenic changes and natural processes affect agriculture primarily by altering soil quality. This paper reviews and synthesizes the available literatures related to the influence of soil management and land use changes on soil carbon (C) stock in Ethiopia. The review shows that topsoil C stock declines approximately 0–63%, 0–23%, and 17–83% upon land use conversion from forest to crop land, to open grazing, and to plantation, respectively. An increase of 1–3% in soil C stock was observed within 10 years of converting open grazed land to protected enclosures. However, there was a little change in soil C stock below 20 cm depth. There is a large potential of increasing SOC pool with adoption of land restorative measures. Total potential of soil C sequestration with the adoption of restoration measures ranges 0·066–2·2 Tg C y−1 on rain‐fed cropland and 4·2–10·5 Tg C y−1 on rangeland. Given large area and diverse ecological conditions in Ethiopia, research data available in published literature are rather scanty. Therefore, researchable priorities identified in this review are important. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
86.
Development of Core Subset of Finger Millet Germplasm Using Geographical Origin and Data on 14 Quantitative Traits 总被引:6,自引:0,他引:6
Hari D. Upadhyaya C. L. L. Gowda R. P. S. Pundir V. Gopal Reddy Sube Singh 《Genetic Resources and Crop Evolution》2006,53(4):679-685
Finger millet [Eleusine coracana (L.) Gaertn.] is an important cereal food crop in Africa and South Asia. It is a hardy crop that can be grown in very diverse
environments from almost at sea level to about 2400 m.a.s.l. Finger millet has an excellent food value as its seeds contain
protein ranging from 7 to 14% and are particularly rich in methionine amino acid, iron, and calcium. Despite all these merits,
this crop has been neglected from the main stream of crop improvement research. One of the means to boost its production and
productivity is to enhance utilization of finger millet germplasm to breed superior varieties. Keeping this objective in view,
a core subset of finger millet germplasm (622 accessions) based on origin and data on 14 quantitative traits was developed
from the entire global collection of 5940 accessions held in the genebank at ICRISAT, Patancheru, India. The comparison of
means, variances, frequency distribution, Shannon-Weaver diversity index (H′) and phenotypic correlations indicated that the
core subset represents the entire collection. These tests indicated that sampling was optimal and the diversity has been captured
very well in the core subset. The correlation analysis indicated that panicle exsertion and longest finger length could be
given lower priority in the future germplasm evaluation work of finger millet. 相似文献
87.
ABSTRACT Zinc (Zn) deficiency is the most prevalent nutritional disorder in citrus orchards world over. The management strategy of Zn deficiency today is still governed by the efficacy of two conventionally used methods of Zn supply to plants via soil or foliar fertilization. A field experiment with 12-yr-old ‘Nagpur’ mandarin (Citrus reticulata Blanco) orchard was, therefore, carried out during 2004–07 comparing soil application versus foliar application of Zn, each at three levels viz., 100, 200, and 300 g tree?1 with constant doses of N (600 g tree?1), P (200 g tree?1), K (300 g tree?1), and Fe(60 g tree?1) on Haplustert soil type with reference to response on flowering intensity, fruit set, tree volume, fruit yield, changes in soil fertility/leaf nutrient status, fruit quality, and transformation of native soil Zn fractions. Soil application of Zn at all the three levels, produced significantly higher increase in tree volume over foliar application on equivalent rates viz., T1 (2.53 m3) vs. T4 (2.06 m3) and T2(4.30 m3) vs. T5 (2.23 m3). The yield-determining parameters like flowering and fruit set intensity (no. m?1 shoot length) were, respectively, much higher with soil applied (135.74 and 21.90) than foliar applied Zn (31.20 and 11.6). These observations set the favorable conditions required for yield response, e.g., all the three treatments involving soil application of Zn, T1 (32.1 kg tree?1), T2 (52.6 kg tree?1), and T3 (51.8 kg tree?1) were correspondingly superior over T4 (22.5 kg tree?1), T5 (34.3 kg tree?1), and T6 (42.1 kg tree?1) as foliar application treatments. All the three major fruit quality parameters (juice, acidity, and TSS) were likewise more influenced by soil application than foliar application of Zn. Improvements in soil Zn fractions (mg kg?1) viz., exchangeable Zn (0.25–0.60), complex-Zn (2.71 to 4.86), organically bound Zn (0.86 to 2.0), and Zn-bound to carbonates and acid soluble minerals (2.56–4.96) were observed in response to Zn fertilization with treatments T1–T3. On the other hand, foliar applied Zn treatments (T4–T6) produced no such changes in any of the soil Zn fractions. 相似文献
88.
Present investigation evaluates the effect of organic fertilization (OF), integrated nutrient management (INM) practice, and recommended dose of chemical fertilization (CF) on changes in soil organic phosphorus (P) and its fractions under rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system. The 4-year experiment (2009–2013), under split-plot design, showed that OF did not increase the total P or total organic P content of soil under either of the test crops. However, OF maintained the higher level of labile organic P and moderately labile organic P in soil under wheat the moderately stable organic P and highly stable organic P was highest in paddy soil under CF practices (11.34 and 7.77 μg g?1, respectively) followed by wheat. The P concentration in organically grown rice or wheat grain was increased significantly compared with their CF counterparts. The productivity economics for rice and wheat crops showed INM fertilization to be more economical than OF. 相似文献
89.
A 66 kDa adult Haemonchus contortus excretory/secretory (E/S) antigen was identified in Western blot by reaction with sera from the infected goats. The protein was purified from the adult worm extract and E/S products by anion exchange and ConA-Sepharose chromatography. The purified protein inhibited monocyte function in vitro as judged by decreased production of hydrogen peroxide and nitric oxide in the culture medium. The protein also caused proliferation of peripheral blood mononuclear cells. The absence of protein in the free living L3 larvae suggests that the expression of this protein coincides with the adaptation to the parasitic life. A correlation of antibody titre and worm burden was observed in the infected goats with higher antibody levels in high worm burdened animals. Anti-protein antibody caused loss of adult worm motility in vitro resulting in the death of the parasite. The fact that the protein is recognized by the host together with in vitro killing of adult parasites by antibodies makes this protein a promising candidate for vaccination trial. 相似文献
90.
Faisal Rashid Sofi S. M. Zofair Vijay Kumar Reddy Surasani K. K. Sabha Nissar Rajkumar Ratankumar Singh 《Journal Of Aquatic Food Product Technology》2013,22(3):253-263
Fatty fish have been recognized as potential raw material for production of minced meat; however, they are prone to oxidation and further deterioration. In the present study, the effect of washing and antioxidant (tannic acid) treatment on the quality of minced meat of Trachurus trachurus (horse mackerel) during frozen storage was observed. Minced meat of Trachurus trachurus was divided into three lots (T0, T1, and T2). T1 was washed with cold water, T2 with cold water containing tannic acid (100 mg/kg), and T0 was not washed. All the lots were frozen at ?40°C and stored at ?20 ± 2°C for 125 days and were subjected to biochemical, microbiological, and sensory evaluation at regular intervals of 25 days. The antioxidant treatment with tannic acid at the dosage used was found effective in minimizing the rancidity problems of minced meat (T2), compared to T0 and T1. During the whole period of storage, samples from T2 showed good quality in terms of microbiological, biochemical, and sensory analysis compared to T1 and T0. 相似文献